xref: /linux/drivers/usb/host/xhci.c (revision f49f4ab95c301dbccad0efe85296d908b8ae7ad4)
1 /*
2  * xHCI host controller driver
3  *
4  * Copyright (C) 2008 Intel Corp.
5  *
6  * Author: Sarah Sharp
7  * Some code borrowed from the Linux EHCI driver.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16  * for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software Foundation,
20  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/pci.h>
24 #include <linux/irq.h>
25 #include <linux/log2.h>
26 #include <linux/module.h>
27 #include <linux/moduleparam.h>
28 #include <linux/slab.h>
29 #include <linux/dmi.h>
30 
31 #include "xhci.h"
32 
33 #define DRIVER_AUTHOR "Sarah Sharp"
34 #define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"
35 
36 /* Some 0.95 hardware can't handle the chain bit on a Link TRB being cleared */
37 static int link_quirk;
38 module_param(link_quirk, int, S_IRUGO | S_IWUSR);
39 MODULE_PARM_DESC(link_quirk, "Don't clear the chain bit on a link TRB");
40 
41 /* TODO: copied from ehci-hcd.c - can this be refactored? */
42 /*
43  * handshake - spin reading hc until handshake completes or fails
44  * @ptr: address of hc register to be read
45  * @mask: bits to look at in result of read
46  * @done: value of those bits when handshake succeeds
47  * @usec: timeout in microseconds
48  *
49  * Returns negative errno, or zero on success
50  *
51  * Success happens when the "mask" bits have the specified value (hardware
52  * handshake done).  There are two failure modes:  "usec" have passed (major
53  * hardware flakeout), or the register reads as all-ones (hardware removed).
54  */
55 int handshake(struct xhci_hcd *xhci, void __iomem *ptr,
56 		      u32 mask, u32 done, int usec)
57 {
58 	u32	result;
59 
60 	do {
61 		result = xhci_readl(xhci, ptr);
62 		if (result == ~(u32)0)		/* card removed */
63 			return -ENODEV;
64 		result &= mask;
65 		if (result == done)
66 			return 0;
67 		udelay(1);
68 		usec--;
69 	} while (usec > 0);
70 	return -ETIMEDOUT;
71 }
72 
73 /*
74  * Disable interrupts and begin the xHCI halting process.
75  */
76 void xhci_quiesce(struct xhci_hcd *xhci)
77 {
78 	u32 halted;
79 	u32 cmd;
80 	u32 mask;
81 
82 	mask = ~(XHCI_IRQS);
83 	halted = xhci_readl(xhci, &xhci->op_regs->status) & STS_HALT;
84 	if (!halted)
85 		mask &= ~CMD_RUN;
86 
87 	cmd = xhci_readl(xhci, &xhci->op_regs->command);
88 	cmd &= mask;
89 	xhci_writel(xhci, cmd, &xhci->op_regs->command);
90 }
91 
92 /*
93  * Force HC into halt state.
94  *
95  * Disable any IRQs and clear the run/stop bit.
96  * HC will complete any current and actively pipelined transactions, and
97  * should halt within 16 ms of the run/stop bit being cleared.
98  * Read HC Halted bit in the status register to see when the HC is finished.
99  */
100 int xhci_halt(struct xhci_hcd *xhci)
101 {
102 	int ret;
103 	xhci_dbg(xhci, "// Halt the HC\n");
104 	xhci_quiesce(xhci);
105 
106 	ret = handshake(xhci, &xhci->op_regs->status,
107 			STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
108 	if (!ret) {
109 		xhci->xhc_state |= XHCI_STATE_HALTED;
110 		xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
111 	} else
112 		xhci_warn(xhci, "Host not halted after %u microseconds.\n",
113 				XHCI_MAX_HALT_USEC);
114 	return ret;
115 }
116 
117 /*
118  * Set the run bit and wait for the host to be running.
119  */
120 static int xhci_start(struct xhci_hcd *xhci)
121 {
122 	u32 temp;
123 	int ret;
124 
125 	temp = xhci_readl(xhci, &xhci->op_regs->command);
126 	temp |= (CMD_RUN);
127 	xhci_dbg(xhci, "// Turn on HC, cmd = 0x%x.\n",
128 			temp);
129 	xhci_writel(xhci, temp, &xhci->op_regs->command);
130 
131 	/*
132 	 * Wait for the HCHalted Status bit to be 0 to indicate the host is
133 	 * running.
134 	 */
135 	ret = handshake(xhci, &xhci->op_regs->status,
136 			STS_HALT, 0, XHCI_MAX_HALT_USEC);
137 	if (ret == -ETIMEDOUT)
138 		xhci_err(xhci, "Host took too long to start, "
139 				"waited %u microseconds.\n",
140 				XHCI_MAX_HALT_USEC);
141 	if (!ret)
142 		xhci->xhc_state &= ~XHCI_STATE_HALTED;
143 	return ret;
144 }
145 
146 /*
147  * Reset a halted HC.
148  *
149  * This resets pipelines, timers, counters, state machines, etc.
150  * Transactions will be terminated immediately, and operational registers
151  * will be set to their defaults.
152  */
153 int xhci_reset(struct xhci_hcd *xhci)
154 {
155 	u32 command;
156 	u32 state;
157 	int ret, i;
158 
159 	state = xhci_readl(xhci, &xhci->op_regs->status);
160 	if ((state & STS_HALT) == 0) {
161 		xhci_warn(xhci, "Host controller not halted, aborting reset.\n");
162 		return 0;
163 	}
164 
165 	xhci_dbg(xhci, "// Reset the HC\n");
166 	command = xhci_readl(xhci, &xhci->op_regs->command);
167 	command |= CMD_RESET;
168 	xhci_writel(xhci, command, &xhci->op_regs->command);
169 
170 	ret = handshake(xhci, &xhci->op_regs->command,
171 			CMD_RESET, 0, 10 * 1000 * 1000);
172 	if (ret)
173 		return ret;
174 
175 	xhci_dbg(xhci, "Wait for controller to be ready for doorbell rings\n");
176 	/*
177 	 * xHCI cannot write to any doorbells or operational registers other
178 	 * than status until the "Controller Not Ready" flag is cleared.
179 	 */
180 	ret = handshake(xhci, &xhci->op_regs->status,
181 			STS_CNR, 0, 10 * 1000 * 1000);
182 
183 	for (i = 0; i < 2; ++i) {
184 		xhci->bus_state[i].port_c_suspend = 0;
185 		xhci->bus_state[i].suspended_ports = 0;
186 		xhci->bus_state[i].resuming_ports = 0;
187 	}
188 
189 	return ret;
190 }
191 
192 #ifdef CONFIG_PCI
193 static int xhci_free_msi(struct xhci_hcd *xhci)
194 {
195 	int i;
196 
197 	if (!xhci->msix_entries)
198 		return -EINVAL;
199 
200 	for (i = 0; i < xhci->msix_count; i++)
201 		if (xhci->msix_entries[i].vector)
202 			free_irq(xhci->msix_entries[i].vector,
203 					xhci_to_hcd(xhci));
204 	return 0;
205 }
206 
207 /*
208  * Set up MSI
209  */
210 static int xhci_setup_msi(struct xhci_hcd *xhci)
211 {
212 	int ret;
213 	struct pci_dev  *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
214 
215 	ret = pci_enable_msi(pdev);
216 	if (ret) {
217 		xhci_dbg(xhci, "failed to allocate MSI entry\n");
218 		return ret;
219 	}
220 
221 	ret = request_irq(pdev->irq, (irq_handler_t)xhci_msi_irq,
222 				0, "xhci_hcd", xhci_to_hcd(xhci));
223 	if (ret) {
224 		xhci_dbg(xhci, "disable MSI interrupt\n");
225 		pci_disable_msi(pdev);
226 	}
227 
228 	return ret;
229 }
230 
231 /*
232  * Free IRQs
233  * free all IRQs request
234  */
235 static void xhci_free_irq(struct xhci_hcd *xhci)
236 {
237 	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
238 	int ret;
239 
240 	/* return if using legacy interrupt */
241 	if (xhci_to_hcd(xhci)->irq > 0)
242 		return;
243 
244 	ret = xhci_free_msi(xhci);
245 	if (!ret)
246 		return;
247 	if (pdev->irq > 0)
248 		free_irq(pdev->irq, xhci_to_hcd(xhci));
249 
250 	return;
251 }
252 
253 /*
254  * Set up MSI-X
255  */
256 static int xhci_setup_msix(struct xhci_hcd *xhci)
257 {
258 	int i, ret = 0;
259 	struct usb_hcd *hcd = xhci_to_hcd(xhci);
260 	struct pci_dev *pdev = to_pci_dev(hcd->self.controller);
261 
262 	/*
263 	 * calculate number of msi-x vectors supported.
264 	 * - HCS_MAX_INTRS: the max number of interrupts the host can handle,
265 	 *   with max number of interrupters based on the xhci HCSPARAMS1.
266 	 * - num_online_cpus: maximum msi-x vectors per CPUs core.
267 	 *   Add additional 1 vector to ensure always available interrupt.
268 	 */
269 	xhci->msix_count = min(num_online_cpus() + 1,
270 				HCS_MAX_INTRS(xhci->hcs_params1));
271 
272 	xhci->msix_entries =
273 		kmalloc((sizeof(struct msix_entry))*xhci->msix_count,
274 				GFP_KERNEL);
275 	if (!xhci->msix_entries) {
276 		xhci_err(xhci, "Failed to allocate MSI-X entries\n");
277 		return -ENOMEM;
278 	}
279 
280 	for (i = 0; i < xhci->msix_count; i++) {
281 		xhci->msix_entries[i].entry = i;
282 		xhci->msix_entries[i].vector = 0;
283 	}
284 
285 	ret = pci_enable_msix(pdev, xhci->msix_entries, xhci->msix_count);
286 	if (ret) {
287 		xhci_dbg(xhci, "Failed to enable MSI-X\n");
288 		goto free_entries;
289 	}
290 
291 	for (i = 0; i < xhci->msix_count; i++) {
292 		ret = request_irq(xhci->msix_entries[i].vector,
293 				(irq_handler_t)xhci_msi_irq,
294 				0, "xhci_hcd", xhci_to_hcd(xhci));
295 		if (ret)
296 			goto disable_msix;
297 	}
298 
299 	hcd->msix_enabled = 1;
300 	return ret;
301 
302 disable_msix:
303 	xhci_dbg(xhci, "disable MSI-X interrupt\n");
304 	xhci_free_irq(xhci);
305 	pci_disable_msix(pdev);
306 free_entries:
307 	kfree(xhci->msix_entries);
308 	xhci->msix_entries = NULL;
309 	return ret;
310 }
311 
312 /* Free any IRQs and disable MSI-X */
313 static void xhci_cleanup_msix(struct xhci_hcd *xhci)
314 {
315 	struct usb_hcd *hcd = xhci_to_hcd(xhci);
316 	struct pci_dev *pdev = to_pci_dev(hcd->self.controller);
317 
318 	xhci_free_irq(xhci);
319 
320 	if (xhci->msix_entries) {
321 		pci_disable_msix(pdev);
322 		kfree(xhci->msix_entries);
323 		xhci->msix_entries = NULL;
324 	} else {
325 		pci_disable_msi(pdev);
326 	}
327 
328 	hcd->msix_enabled = 0;
329 	return;
330 }
331 
332 static void xhci_msix_sync_irqs(struct xhci_hcd *xhci)
333 {
334 	int i;
335 
336 	if (xhci->msix_entries) {
337 		for (i = 0; i < xhci->msix_count; i++)
338 			synchronize_irq(xhci->msix_entries[i].vector);
339 	}
340 }
341 
342 static int xhci_try_enable_msi(struct usb_hcd *hcd)
343 {
344 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
345 	struct pci_dev  *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
346 	int ret;
347 
348 	/*
349 	 * Some Fresco Logic host controllers advertise MSI, but fail to
350 	 * generate interrupts.  Don't even try to enable MSI.
351 	 */
352 	if (xhci->quirks & XHCI_BROKEN_MSI)
353 		return 0;
354 
355 	/* unregister the legacy interrupt */
356 	if (hcd->irq)
357 		free_irq(hcd->irq, hcd);
358 	hcd->irq = 0;
359 
360 	ret = xhci_setup_msix(xhci);
361 	if (ret)
362 		/* fall back to msi*/
363 		ret = xhci_setup_msi(xhci);
364 
365 	if (!ret)
366 		/* hcd->irq is 0, we have MSI */
367 		return 0;
368 
369 	if (!pdev->irq) {
370 		xhci_err(xhci, "No msi-x/msi found and no IRQ in BIOS\n");
371 		return -EINVAL;
372 	}
373 
374 	/* fall back to legacy interrupt*/
375 	ret = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,
376 			hcd->irq_descr, hcd);
377 	if (ret) {
378 		xhci_err(xhci, "request interrupt %d failed\n",
379 				pdev->irq);
380 		return ret;
381 	}
382 	hcd->irq = pdev->irq;
383 	return 0;
384 }
385 
386 #else
387 
388 static int xhci_try_enable_msi(struct usb_hcd *hcd)
389 {
390 	return 0;
391 }
392 
393 static void xhci_cleanup_msix(struct xhci_hcd *xhci)
394 {
395 }
396 
397 static void xhci_msix_sync_irqs(struct xhci_hcd *xhci)
398 {
399 }
400 
401 #endif
402 
403 static void compliance_mode_recovery(unsigned long arg)
404 {
405 	struct xhci_hcd *xhci;
406 	struct usb_hcd *hcd;
407 	u32 temp;
408 	int i;
409 
410 	xhci = (struct xhci_hcd *)arg;
411 
412 	for (i = 0; i < xhci->num_usb3_ports; i++) {
413 		temp = xhci_readl(xhci, xhci->usb3_ports[i]);
414 		if ((temp & PORT_PLS_MASK) == USB_SS_PORT_LS_COMP_MOD) {
415 			/*
416 			 * Compliance Mode Detected. Letting USB Core
417 			 * handle the Warm Reset
418 			 */
419 			xhci_dbg(xhci, "Compliance Mode Detected->Port %d!\n",
420 					i + 1);
421 			xhci_dbg(xhci, "Attempting Recovery routine!\n");
422 			hcd = xhci->shared_hcd;
423 
424 			if (hcd->state == HC_STATE_SUSPENDED)
425 				usb_hcd_resume_root_hub(hcd);
426 
427 			usb_hcd_poll_rh_status(hcd);
428 		}
429 	}
430 
431 	if (xhci->port_status_u0 != ((1 << xhci->num_usb3_ports)-1))
432 		mod_timer(&xhci->comp_mode_recovery_timer,
433 			jiffies + msecs_to_jiffies(COMP_MODE_RCVRY_MSECS));
434 }
435 
436 /*
437  * Quirk to work around issue generated by the SN65LVPE502CP USB3.0 re-driver
438  * that causes ports behind that hardware to enter compliance mode sometimes.
439  * The quirk creates a timer that polls every 2 seconds the link state of
440  * each host controller's port and recovers it by issuing a Warm reset
441  * if Compliance mode is detected, otherwise the port will become "dead" (no
442  * device connections or disconnections will be detected anymore). Becasue no
443  * status event is generated when entering compliance mode (per xhci spec),
444  * this quirk is needed on systems that have the failing hardware installed.
445  */
446 static void compliance_mode_recovery_timer_init(struct xhci_hcd *xhci)
447 {
448 	xhci->port_status_u0 = 0;
449 	init_timer(&xhci->comp_mode_recovery_timer);
450 
451 	xhci->comp_mode_recovery_timer.data = (unsigned long) xhci;
452 	xhci->comp_mode_recovery_timer.function = compliance_mode_recovery;
453 	xhci->comp_mode_recovery_timer.expires = jiffies +
454 			msecs_to_jiffies(COMP_MODE_RCVRY_MSECS);
455 
456 	set_timer_slack(&xhci->comp_mode_recovery_timer,
457 			msecs_to_jiffies(COMP_MODE_RCVRY_MSECS));
458 	add_timer(&xhci->comp_mode_recovery_timer);
459 	xhci_dbg(xhci, "Compliance Mode Recovery Timer Initialized.\n");
460 }
461 
462 /*
463  * This function identifies the systems that have installed the SN65LVPE502CP
464  * USB3.0 re-driver and that need the Compliance Mode Quirk.
465  * Systems:
466  * Vendor: Hewlett-Packard -> System Models: Z420, Z620 and Z820
467  */
468 static bool compliance_mode_recovery_timer_quirk_check(void)
469 {
470 	const char *dmi_product_name, *dmi_sys_vendor;
471 
472 	dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
473 	dmi_sys_vendor = dmi_get_system_info(DMI_SYS_VENDOR);
474 	if (!dmi_product_name || !dmi_sys_vendor)
475 		return false;
476 
477 	if (!(strstr(dmi_sys_vendor, "Hewlett-Packard")))
478 		return false;
479 
480 	if (strstr(dmi_product_name, "Z420") ||
481 			strstr(dmi_product_name, "Z620") ||
482 			strstr(dmi_product_name, "Z820") ||
483 			strstr(dmi_product_name, "Z1"))
484 		return true;
485 
486 	return false;
487 }
488 
489 static int xhci_all_ports_seen_u0(struct xhci_hcd *xhci)
490 {
491 	return (xhci->port_status_u0 == ((1 << xhci->num_usb3_ports)-1));
492 }
493 
494 
495 /*
496  * Initialize memory for HCD and xHC (one-time init).
497  *
498  * Program the PAGESIZE register, initialize the device context array, create
499  * device contexts (?), set up a command ring segment (or two?), create event
500  * ring (one for now).
501  */
502 int xhci_init(struct usb_hcd *hcd)
503 {
504 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
505 	int retval = 0;
506 
507 	xhci_dbg(xhci, "xhci_init\n");
508 	spin_lock_init(&xhci->lock);
509 	if (xhci->hci_version == 0x95 && link_quirk) {
510 		xhci_dbg(xhci, "QUIRK: Not clearing Link TRB chain bits.\n");
511 		xhci->quirks |= XHCI_LINK_TRB_QUIRK;
512 	} else {
513 		xhci_dbg(xhci, "xHCI doesn't need link TRB QUIRK\n");
514 	}
515 	retval = xhci_mem_init(xhci, GFP_KERNEL);
516 	xhci_dbg(xhci, "Finished xhci_init\n");
517 
518 	/* Initializing Compliance Mode Recovery Data If Needed */
519 	if (compliance_mode_recovery_timer_quirk_check()) {
520 		xhci->quirks |= XHCI_COMP_MODE_QUIRK;
521 		compliance_mode_recovery_timer_init(xhci);
522 	}
523 
524 	return retval;
525 }
526 
527 /*-------------------------------------------------------------------------*/
528 
529 
530 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
531 static void xhci_event_ring_work(unsigned long arg)
532 {
533 	unsigned long flags;
534 	int temp;
535 	u64 temp_64;
536 	struct xhci_hcd *xhci = (struct xhci_hcd *) arg;
537 	int i, j;
538 
539 	xhci_dbg(xhci, "Poll event ring: %lu\n", jiffies);
540 
541 	spin_lock_irqsave(&xhci->lock, flags);
542 	temp = xhci_readl(xhci, &xhci->op_regs->status);
543 	xhci_dbg(xhci, "op reg status = 0x%x\n", temp);
544 	if (temp == 0xffffffff || (xhci->xhc_state & XHCI_STATE_DYING) ||
545 			(xhci->xhc_state & XHCI_STATE_HALTED)) {
546 		xhci_dbg(xhci, "HW died, polling stopped.\n");
547 		spin_unlock_irqrestore(&xhci->lock, flags);
548 		return;
549 	}
550 
551 	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
552 	xhci_dbg(xhci, "ir_set 0 pending = 0x%x\n", temp);
553 	xhci_dbg(xhci, "HC error bitmask = 0x%x\n", xhci->error_bitmask);
554 	xhci->error_bitmask = 0;
555 	xhci_dbg(xhci, "Event ring:\n");
556 	xhci_debug_segment(xhci, xhci->event_ring->deq_seg);
557 	xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
558 	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
559 	temp_64 &= ~ERST_PTR_MASK;
560 	xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
561 	xhci_dbg(xhci, "Command ring:\n");
562 	xhci_debug_segment(xhci, xhci->cmd_ring->deq_seg);
563 	xhci_dbg_ring_ptrs(xhci, xhci->cmd_ring);
564 	xhci_dbg_cmd_ptrs(xhci);
565 	for (i = 0; i < MAX_HC_SLOTS; ++i) {
566 		if (!xhci->devs[i])
567 			continue;
568 		for (j = 0; j < 31; ++j) {
569 			xhci_dbg_ep_rings(xhci, i, j, &xhci->devs[i]->eps[j]);
570 		}
571 	}
572 	spin_unlock_irqrestore(&xhci->lock, flags);
573 
574 	if (!xhci->zombie)
575 		mod_timer(&xhci->event_ring_timer, jiffies + POLL_TIMEOUT * HZ);
576 	else
577 		xhci_dbg(xhci, "Quit polling the event ring.\n");
578 }
579 #endif
580 
581 static int xhci_run_finished(struct xhci_hcd *xhci)
582 {
583 	if (xhci_start(xhci)) {
584 		xhci_halt(xhci);
585 		return -ENODEV;
586 	}
587 	xhci->shared_hcd->state = HC_STATE_RUNNING;
588 	xhci->cmd_ring_state = CMD_RING_STATE_RUNNING;
589 
590 	if (xhci->quirks & XHCI_NEC_HOST)
591 		xhci_ring_cmd_db(xhci);
592 
593 	xhci_dbg(xhci, "Finished xhci_run for USB3 roothub\n");
594 	return 0;
595 }
596 
597 /*
598  * Start the HC after it was halted.
599  *
600  * This function is called by the USB core when the HC driver is added.
601  * Its opposite is xhci_stop().
602  *
603  * xhci_init() must be called once before this function can be called.
604  * Reset the HC, enable device slot contexts, program DCBAAP, and
605  * set command ring pointer and event ring pointer.
606  *
607  * Setup MSI-X vectors and enable interrupts.
608  */
609 int xhci_run(struct usb_hcd *hcd)
610 {
611 	u32 temp;
612 	u64 temp_64;
613 	int ret;
614 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
615 
616 	/* Start the xHCI host controller running only after the USB 2.0 roothub
617 	 * is setup.
618 	 */
619 
620 	hcd->uses_new_polling = 1;
621 	if (!usb_hcd_is_primary_hcd(hcd))
622 		return xhci_run_finished(xhci);
623 
624 	xhci_dbg(xhci, "xhci_run\n");
625 
626 	ret = xhci_try_enable_msi(hcd);
627 	if (ret)
628 		return ret;
629 
630 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
631 	init_timer(&xhci->event_ring_timer);
632 	xhci->event_ring_timer.data = (unsigned long) xhci;
633 	xhci->event_ring_timer.function = xhci_event_ring_work;
634 	/* Poll the event ring */
635 	xhci->event_ring_timer.expires = jiffies + POLL_TIMEOUT * HZ;
636 	xhci->zombie = 0;
637 	xhci_dbg(xhci, "Setting event ring polling timer\n");
638 	add_timer(&xhci->event_ring_timer);
639 #endif
640 
641 	xhci_dbg(xhci, "Command ring memory map follows:\n");
642 	xhci_debug_ring(xhci, xhci->cmd_ring);
643 	xhci_dbg_ring_ptrs(xhci, xhci->cmd_ring);
644 	xhci_dbg_cmd_ptrs(xhci);
645 
646 	xhci_dbg(xhci, "ERST memory map follows:\n");
647 	xhci_dbg_erst(xhci, &xhci->erst);
648 	xhci_dbg(xhci, "Event ring:\n");
649 	xhci_debug_ring(xhci, xhci->event_ring);
650 	xhci_dbg_ring_ptrs(xhci, xhci->event_ring);
651 	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
652 	temp_64 &= ~ERST_PTR_MASK;
653 	xhci_dbg(xhci, "ERST deq = 64'h%0lx\n", (long unsigned int) temp_64);
654 
655 	xhci_dbg(xhci, "// Set the interrupt modulation register\n");
656 	temp = xhci_readl(xhci, &xhci->ir_set->irq_control);
657 	temp &= ~ER_IRQ_INTERVAL_MASK;
658 	temp |= (u32) 160;
659 	xhci_writel(xhci, temp, &xhci->ir_set->irq_control);
660 
661 	/* Set the HCD state before we enable the irqs */
662 	temp = xhci_readl(xhci, &xhci->op_regs->command);
663 	temp |= (CMD_EIE);
664 	xhci_dbg(xhci, "// Enable interrupts, cmd = 0x%x.\n",
665 			temp);
666 	xhci_writel(xhci, temp, &xhci->op_regs->command);
667 
668 	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
669 	xhci_dbg(xhci, "// Enabling event ring interrupter %p by writing 0x%x to irq_pending\n",
670 			xhci->ir_set, (unsigned int) ER_IRQ_ENABLE(temp));
671 	xhci_writel(xhci, ER_IRQ_ENABLE(temp),
672 			&xhci->ir_set->irq_pending);
673 	xhci_print_ir_set(xhci, 0);
674 
675 	if (xhci->quirks & XHCI_NEC_HOST)
676 		xhci_queue_vendor_command(xhci, 0, 0, 0,
677 				TRB_TYPE(TRB_NEC_GET_FW));
678 
679 	xhci_dbg(xhci, "Finished xhci_run for USB2 roothub\n");
680 	return 0;
681 }
682 
683 static void xhci_only_stop_hcd(struct usb_hcd *hcd)
684 {
685 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
686 
687 	spin_lock_irq(&xhci->lock);
688 	xhci_halt(xhci);
689 
690 	/* The shared_hcd is going to be deallocated shortly (the USB core only
691 	 * calls this function when allocation fails in usb_add_hcd(), or
692 	 * usb_remove_hcd() is called).  So we need to unset xHCI's pointer.
693 	 */
694 	xhci->shared_hcd = NULL;
695 	spin_unlock_irq(&xhci->lock);
696 }
697 
698 /*
699  * Stop xHCI driver.
700  *
701  * This function is called by the USB core when the HC driver is removed.
702  * Its opposite is xhci_run().
703  *
704  * Disable device contexts, disable IRQs, and quiesce the HC.
705  * Reset the HC, finish any completed transactions, and cleanup memory.
706  */
707 void xhci_stop(struct usb_hcd *hcd)
708 {
709 	u32 temp;
710 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
711 
712 	if (!usb_hcd_is_primary_hcd(hcd)) {
713 		xhci_only_stop_hcd(xhci->shared_hcd);
714 		return;
715 	}
716 
717 	spin_lock_irq(&xhci->lock);
718 	/* Make sure the xHC is halted for a USB3 roothub
719 	 * (xhci_stop() could be called as part of failed init).
720 	 */
721 	xhci_halt(xhci);
722 	xhci_reset(xhci);
723 	spin_unlock_irq(&xhci->lock);
724 
725 	xhci_cleanup_msix(xhci);
726 
727 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
728 	/* Tell the event ring poll function not to reschedule */
729 	xhci->zombie = 1;
730 	del_timer_sync(&xhci->event_ring_timer);
731 #endif
732 
733 	/* Deleting Compliance Mode Recovery Timer */
734 	if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
735 			(!(xhci_all_ports_seen_u0(xhci))))
736 		del_timer_sync(&xhci->comp_mode_recovery_timer);
737 
738 	if (xhci->quirks & XHCI_AMD_PLL_FIX)
739 		usb_amd_dev_put();
740 
741 	xhci_dbg(xhci, "// Disabling event ring interrupts\n");
742 	temp = xhci_readl(xhci, &xhci->op_regs->status);
743 	xhci_writel(xhci, temp & ~STS_EINT, &xhci->op_regs->status);
744 	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
745 	xhci_writel(xhci, ER_IRQ_DISABLE(temp),
746 			&xhci->ir_set->irq_pending);
747 	xhci_print_ir_set(xhci, 0);
748 
749 	xhci_dbg(xhci, "cleaning up memory\n");
750 	xhci_mem_cleanup(xhci);
751 	xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
752 		    xhci_readl(xhci, &xhci->op_regs->status));
753 }
754 
755 /*
756  * Shutdown HC (not bus-specific)
757  *
758  * This is called when the machine is rebooting or halting.  We assume that the
759  * machine will be powered off, and the HC's internal state will be reset.
760  * Don't bother to free memory.
761  *
762  * This will only ever be called with the main usb_hcd (the USB3 roothub).
763  */
764 void xhci_shutdown(struct usb_hcd *hcd)
765 {
766 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
767 
768 	if (xhci->quirks & XHCI_SPURIOUS_REBOOT)
769 		usb_disable_xhci_ports(to_pci_dev(hcd->self.controller));
770 
771 	spin_lock_irq(&xhci->lock);
772 	xhci_halt(xhci);
773 	spin_unlock_irq(&xhci->lock);
774 
775 	xhci_cleanup_msix(xhci);
776 
777 	xhci_dbg(xhci, "xhci_shutdown completed - status = %x\n",
778 		    xhci_readl(xhci, &xhci->op_regs->status));
779 }
780 
781 #ifdef CONFIG_PM
782 static void xhci_save_registers(struct xhci_hcd *xhci)
783 {
784 	xhci->s3.command = xhci_readl(xhci, &xhci->op_regs->command);
785 	xhci->s3.dev_nt = xhci_readl(xhci, &xhci->op_regs->dev_notification);
786 	xhci->s3.dcbaa_ptr = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
787 	xhci->s3.config_reg = xhci_readl(xhci, &xhci->op_regs->config_reg);
788 	xhci->s3.erst_size = xhci_readl(xhci, &xhci->ir_set->erst_size);
789 	xhci->s3.erst_base = xhci_read_64(xhci, &xhci->ir_set->erst_base);
790 	xhci->s3.erst_dequeue = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
791 	xhci->s3.irq_pending = xhci_readl(xhci, &xhci->ir_set->irq_pending);
792 	xhci->s3.irq_control = xhci_readl(xhci, &xhci->ir_set->irq_control);
793 }
794 
795 static void xhci_restore_registers(struct xhci_hcd *xhci)
796 {
797 	xhci_writel(xhci, xhci->s3.command, &xhci->op_regs->command);
798 	xhci_writel(xhci, xhci->s3.dev_nt, &xhci->op_regs->dev_notification);
799 	xhci_write_64(xhci, xhci->s3.dcbaa_ptr, &xhci->op_regs->dcbaa_ptr);
800 	xhci_writel(xhci, xhci->s3.config_reg, &xhci->op_regs->config_reg);
801 	xhci_writel(xhci, xhci->s3.erst_size, &xhci->ir_set->erst_size);
802 	xhci_write_64(xhci, xhci->s3.erst_base, &xhci->ir_set->erst_base);
803 	xhci_write_64(xhci, xhci->s3.erst_dequeue, &xhci->ir_set->erst_dequeue);
804 	xhci_writel(xhci, xhci->s3.irq_pending, &xhci->ir_set->irq_pending);
805 	xhci_writel(xhci, xhci->s3.irq_control, &xhci->ir_set->irq_control);
806 }
807 
808 static void xhci_set_cmd_ring_deq(struct xhci_hcd *xhci)
809 {
810 	u64	val_64;
811 
812 	/* step 2: initialize command ring buffer */
813 	val_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
814 	val_64 = (val_64 & (u64) CMD_RING_RSVD_BITS) |
815 		(xhci_trb_virt_to_dma(xhci->cmd_ring->deq_seg,
816 				      xhci->cmd_ring->dequeue) &
817 		 (u64) ~CMD_RING_RSVD_BITS) |
818 		xhci->cmd_ring->cycle_state;
819 	xhci_dbg(xhci, "// Setting command ring address to 0x%llx\n",
820 			(long unsigned long) val_64);
821 	xhci_write_64(xhci, val_64, &xhci->op_regs->cmd_ring);
822 }
823 
824 /*
825  * The whole command ring must be cleared to zero when we suspend the host.
826  *
827  * The host doesn't save the command ring pointer in the suspend well, so we
828  * need to re-program it on resume.  Unfortunately, the pointer must be 64-byte
829  * aligned, because of the reserved bits in the command ring dequeue pointer
830  * register.  Therefore, we can't just set the dequeue pointer back in the
831  * middle of the ring (TRBs are 16-byte aligned).
832  */
833 static void xhci_clear_command_ring(struct xhci_hcd *xhci)
834 {
835 	struct xhci_ring *ring;
836 	struct xhci_segment *seg;
837 
838 	ring = xhci->cmd_ring;
839 	seg = ring->deq_seg;
840 	do {
841 		memset(seg->trbs, 0,
842 			sizeof(union xhci_trb) * (TRBS_PER_SEGMENT - 1));
843 		seg->trbs[TRBS_PER_SEGMENT - 1].link.control &=
844 			cpu_to_le32(~TRB_CYCLE);
845 		seg = seg->next;
846 	} while (seg != ring->deq_seg);
847 
848 	/* Reset the software enqueue and dequeue pointers */
849 	ring->deq_seg = ring->first_seg;
850 	ring->dequeue = ring->first_seg->trbs;
851 	ring->enq_seg = ring->deq_seg;
852 	ring->enqueue = ring->dequeue;
853 
854 	ring->num_trbs_free = ring->num_segs * (TRBS_PER_SEGMENT - 1) - 1;
855 	/*
856 	 * Ring is now zeroed, so the HW should look for change of ownership
857 	 * when the cycle bit is set to 1.
858 	 */
859 	ring->cycle_state = 1;
860 
861 	/*
862 	 * Reset the hardware dequeue pointer.
863 	 * Yes, this will need to be re-written after resume, but we're paranoid
864 	 * and want to make sure the hardware doesn't access bogus memory
865 	 * because, say, the BIOS or an SMI started the host without changing
866 	 * the command ring pointers.
867 	 */
868 	xhci_set_cmd_ring_deq(xhci);
869 }
870 
871 /*
872  * Stop HC (not bus-specific)
873  *
874  * This is called when the machine transition into S3/S4 mode.
875  *
876  */
877 int xhci_suspend(struct xhci_hcd *xhci)
878 {
879 	int			rc = 0;
880 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
881 	u32			command;
882 
883 	spin_lock_irq(&xhci->lock);
884 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
885 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
886 	/* step 1: stop endpoint */
887 	/* skipped assuming that port suspend has done */
888 
889 	/* step 2: clear Run/Stop bit */
890 	command = xhci_readl(xhci, &xhci->op_regs->command);
891 	command &= ~CMD_RUN;
892 	xhci_writel(xhci, command, &xhci->op_regs->command);
893 	if (handshake(xhci, &xhci->op_regs->status,
894 		      STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC)) {
895 		xhci_warn(xhci, "WARN: xHC CMD_RUN timeout\n");
896 		spin_unlock_irq(&xhci->lock);
897 		return -ETIMEDOUT;
898 	}
899 	xhci_clear_command_ring(xhci);
900 
901 	/* step 3: save registers */
902 	xhci_save_registers(xhci);
903 
904 	/* step 4: set CSS flag */
905 	command = xhci_readl(xhci, &xhci->op_regs->command);
906 	command |= CMD_CSS;
907 	xhci_writel(xhci, command, &xhci->op_regs->command);
908 	if (handshake(xhci, &xhci->op_regs->status, STS_SAVE, 0, 10 * 1000)) {
909 		xhci_warn(xhci, "WARN: xHC save state timeout\n");
910 		spin_unlock_irq(&xhci->lock);
911 		return -ETIMEDOUT;
912 	}
913 	spin_unlock_irq(&xhci->lock);
914 
915 	/*
916 	 * Deleting Compliance Mode Recovery Timer because the xHCI Host
917 	 * is about to be suspended.
918 	 */
919 	if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
920 			(!(xhci_all_ports_seen_u0(xhci)))) {
921 		del_timer_sync(&xhci->comp_mode_recovery_timer);
922 		xhci_dbg(xhci, "Compliance Mode Recovery Timer Deleted!\n");
923 	}
924 
925 	/* step 5: remove core well power */
926 	/* synchronize irq when using MSI-X */
927 	xhci_msix_sync_irqs(xhci);
928 
929 	return rc;
930 }
931 
932 /*
933  * start xHC (not bus-specific)
934  *
935  * This is called when the machine transition from S3/S4 mode.
936  *
937  */
938 int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
939 {
940 	u32			command, temp = 0;
941 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
942 	struct usb_hcd		*secondary_hcd;
943 	int			retval = 0;
944 
945 	/* Wait a bit if either of the roothubs need to settle from the
946 	 * transition into bus suspend.
947 	 */
948 	if (time_before(jiffies, xhci->bus_state[0].next_statechange) ||
949 			time_before(jiffies,
950 				xhci->bus_state[1].next_statechange))
951 		msleep(100);
952 
953 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
954 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
955 
956 	spin_lock_irq(&xhci->lock);
957 	if (xhci->quirks & XHCI_RESET_ON_RESUME)
958 		hibernated = true;
959 
960 	if (!hibernated) {
961 		/* step 1: restore register */
962 		xhci_restore_registers(xhci);
963 		/* step 2: initialize command ring buffer */
964 		xhci_set_cmd_ring_deq(xhci);
965 		/* step 3: restore state and start state*/
966 		/* step 3: set CRS flag */
967 		command = xhci_readl(xhci, &xhci->op_regs->command);
968 		command |= CMD_CRS;
969 		xhci_writel(xhci, command, &xhci->op_regs->command);
970 		if (handshake(xhci, &xhci->op_regs->status,
971 			      STS_RESTORE, 0, 10 * 1000)) {
972 			xhci_warn(xhci, "WARN: xHC restore state timeout\n");
973 			spin_unlock_irq(&xhci->lock);
974 			return -ETIMEDOUT;
975 		}
976 		temp = xhci_readl(xhci, &xhci->op_regs->status);
977 	}
978 
979 	/* If restore operation fails, re-initialize the HC during resume */
980 	if ((temp & STS_SRE) || hibernated) {
981 		/* Let the USB core know _both_ roothubs lost power. */
982 		usb_root_hub_lost_power(xhci->main_hcd->self.root_hub);
983 		usb_root_hub_lost_power(xhci->shared_hcd->self.root_hub);
984 
985 		xhci_dbg(xhci, "Stop HCD\n");
986 		xhci_halt(xhci);
987 		xhci_reset(xhci);
988 		spin_unlock_irq(&xhci->lock);
989 		xhci_cleanup_msix(xhci);
990 
991 #ifdef CONFIG_USB_XHCI_HCD_DEBUGGING
992 		/* Tell the event ring poll function not to reschedule */
993 		xhci->zombie = 1;
994 		del_timer_sync(&xhci->event_ring_timer);
995 #endif
996 
997 		xhci_dbg(xhci, "// Disabling event ring interrupts\n");
998 		temp = xhci_readl(xhci, &xhci->op_regs->status);
999 		xhci_writel(xhci, temp & ~STS_EINT, &xhci->op_regs->status);
1000 		temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
1001 		xhci_writel(xhci, ER_IRQ_DISABLE(temp),
1002 				&xhci->ir_set->irq_pending);
1003 		xhci_print_ir_set(xhci, 0);
1004 
1005 		xhci_dbg(xhci, "cleaning up memory\n");
1006 		xhci_mem_cleanup(xhci);
1007 		xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
1008 			    xhci_readl(xhci, &xhci->op_regs->status));
1009 
1010 		/* USB core calls the PCI reinit and start functions twice:
1011 		 * first with the primary HCD, and then with the secondary HCD.
1012 		 * If we don't do the same, the host will never be started.
1013 		 */
1014 		if (!usb_hcd_is_primary_hcd(hcd))
1015 			secondary_hcd = hcd;
1016 		else
1017 			secondary_hcd = xhci->shared_hcd;
1018 
1019 		xhci_dbg(xhci, "Initialize the xhci_hcd\n");
1020 		retval = xhci_init(hcd->primary_hcd);
1021 		if (retval)
1022 			return retval;
1023 		xhci_dbg(xhci, "Start the primary HCD\n");
1024 		retval = xhci_run(hcd->primary_hcd);
1025 		if (!retval) {
1026 			xhci_dbg(xhci, "Start the secondary HCD\n");
1027 			retval = xhci_run(secondary_hcd);
1028 		}
1029 		hcd->state = HC_STATE_SUSPENDED;
1030 		xhci->shared_hcd->state = HC_STATE_SUSPENDED;
1031 		goto done;
1032 	}
1033 
1034 	/* step 4: set Run/Stop bit */
1035 	command = xhci_readl(xhci, &xhci->op_regs->command);
1036 	command |= CMD_RUN;
1037 	xhci_writel(xhci, command, &xhci->op_regs->command);
1038 	handshake(xhci, &xhci->op_regs->status, STS_HALT,
1039 		  0, 250 * 1000);
1040 
1041 	/* step 5: walk topology and initialize portsc,
1042 	 * portpmsc and portli
1043 	 */
1044 	/* this is done in bus_resume */
1045 
1046 	/* step 6: restart each of the previously
1047 	 * Running endpoints by ringing their doorbells
1048 	 */
1049 
1050 	spin_unlock_irq(&xhci->lock);
1051 
1052  done:
1053 	if (retval == 0) {
1054 		usb_hcd_resume_root_hub(hcd);
1055 		usb_hcd_resume_root_hub(xhci->shared_hcd);
1056 	}
1057 
1058 	/*
1059 	 * If system is subject to the Quirk, Compliance Mode Timer needs to
1060 	 * be re-initialized Always after a system resume. Ports are subject
1061 	 * to suffer the Compliance Mode issue again. It doesn't matter if
1062 	 * ports have entered previously to U0 before system's suspension.
1063 	 */
1064 	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
1065 		compliance_mode_recovery_timer_init(xhci);
1066 
1067 	return retval;
1068 }
1069 #endif	/* CONFIG_PM */
1070 
1071 /*-------------------------------------------------------------------------*/
1072 
1073 /**
1074  * xhci_get_endpoint_index - Used for passing endpoint bitmasks between the core and
1075  * HCDs.  Find the index for an endpoint given its descriptor.  Use the return
1076  * value to right shift 1 for the bitmask.
1077  *
1078  * Index  = (epnum * 2) + direction - 1,
1079  * where direction = 0 for OUT, 1 for IN.
1080  * For control endpoints, the IN index is used (OUT index is unused), so
1081  * index = (epnum * 2) + direction - 1 = (epnum * 2) + 1 - 1 = (epnum * 2)
1082  */
1083 unsigned int xhci_get_endpoint_index(struct usb_endpoint_descriptor *desc)
1084 {
1085 	unsigned int index;
1086 	if (usb_endpoint_xfer_control(desc))
1087 		index = (unsigned int) (usb_endpoint_num(desc)*2);
1088 	else
1089 		index = (unsigned int) (usb_endpoint_num(desc)*2) +
1090 			(usb_endpoint_dir_in(desc) ? 1 : 0) - 1;
1091 	return index;
1092 }
1093 
1094 /* Find the flag for this endpoint (for use in the control context).  Use the
1095  * endpoint index to create a bitmask.  The slot context is bit 0, endpoint 0 is
1096  * bit 1, etc.
1097  */
1098 unsigned int xhci_get_endpoint_flag(struct usb_endpoint_descriptor *desc)
1099 {
1100 	return 1 << (xhci_get_endpoint_index(desc) + 1);
1101 }
1102 
1103 /* Find the flag for this endpoint (for use in the control context).  Use the
1104  * endpoint index to create a bitmask.  The slot context is bit 0, endpoint 0 is
1105  * bit 1, etc.
1106  */
1107 unsigned int xhci_get_endpoint_flag_from_index(unsigned int ep_index)
1108 {
1109 	return 1 << (ep_index + 1);
1110 }
1111 
1112 /* Compute the last valid endpoint context index.  Basically, this is the
1113  * endpoint index plus one.  For slot contexts with more than valid endpoint,
1114  * we find the most significant bit set in the added contexts flags.
1115  * e.g. ep 1 IN (with epnum 0x81) => added_ctxs = 0b1000
1116  * fls(0b1000) = 4, but the endpoint context index is 3, so subtract one.
1117  */
1118 unsigned int xhci_last_valid_endpoint(u32 added_ctxs)
1119 {
1120 	return fls(added_ctxs) - 1;
1121 }
1122 
1123 /* Returns 1 if the arguments are OK;
1124  * returns 0 this is a root hub; returns -EINVAL for NULL pointers.
1125  */
1126 static int xhci_check_args(struct usb_hcd *hcd, struct usb_device *udev,
1127 		struct usb_host_endpoint *ep, int check_ep, bool check_virt_dev,
1128 		const char *func) {
1129 	struct xhci_hcd	*xhci;
1130 	struct xhci_virt_device	*virt_dev;
1131 
1132 	if (!hcd || (check_ep && !ep) || !udev) {
1133 		printk(KERN_DEBUG "xHCI %s called with invalid args\n",
1134 				func);
1135 		return -EINVAL;
1136 	}
1137 	if (!udev->parent) {
1138 		printk(KERN_DEBUG "xHCI %s called for root hub\n",
1139 				func);
1140 		return 0;
1141 	}
1142 
1143 	xhci = hcd_to_xhci(hcd);
1144 	if (xhci->xhc_state & XHCI_STATE_HALTED)
1145 		return -ENODEV;
1146 
1147 	if (check_virt_dev) {
1148 		if (!udev->slot_id || !xhci->devs[udev->slot_id]) {
1149 			printk(KERN_DEBUG "xHCI %s called with unaddressed "
1150 						"device\n", func);
1151 			return -EINVAL;
1152 		}
1153 
1154 		virt_dev = xhci->devs[udev->slot_id];
1155 		if (virt_dev->udev != udev) {
1156 			printk(KERN_DEBUG "xHCI %s called with udev and "
1157 					  "virt_dev does not match\n", func);
1158 			return -EINVAL;
1159 		}
1160 	}
1161 
1162 	return 1;
1163 }
1164 
1165 static int xhci_configure_endpoint(struct xhci_hcd *xhci,
1166 		struct usb_device *udev, struct xhci_command *command,
1167 		bool ctx_change, bool must_succeed);
1168 
1169 /*
1170  * Full speed devices may have a max packet size greater than 8 bytes, but the
1171  * USB core doesn't know that until it reads the first 8 bytes of the
1172  * descriptor.  If the usb_device's max packet size changes after that point,
1173  * we need to issue an evaluate context command and wait on it.
1174  */
1175 static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id,
1176 		unsigned int ep_index, struct urb *urb)
1177 {
1178 	struct xhci_container_ctx *in_ctx;
1179 	struct xhci_container_ctx *out_ctx;
1180 	struct xhci_input_control_ctx *ctrl_ctx;
1181 	struct xhci_ep_ctx *ep_ctx;
1182 	int max_packet_size;
1183 	int hw_max_packet_size;
1184 	int ret = 0;
1185 
1186 	out_ctx = xhci->devs[slot_id]->out_ctx;
1187 	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
1188 	hw_max_packet_size = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
1189 	max_packet_size = usb_endpoint_maxp(&urb->dev->ep0.desc);
1190 	if (hw_max_packet_size != max_packet_size) {
1191 		xhci_dbg(xhci, "Max Packet Size for ep 0 changed.\n");
1192 		xhci_dbg(xhci, "Max packet size in usb_device = %d\n",
1193 				max_packet_size);
1194 		xhci_dbg(xhci, "Max packet size in xHCI HW = %d\n",
1195 				hw_max_packet_size);
1196 		xhci_dbg(xhci, "Issuing evaluate context command.\n");
1197 
1198 		/* Set up the modified control endpoint 0 */
1199 		xhci_endpoint_copy(xhci, xhci->devs[slot_id]->in_ctx,
1200 				xhci->devs[slot_id]->out_ctx, ep_index);
1201 		in_ctx = xhci->devs[slot_id]->in_ctx;
1202 		ep_ctx = xhci_get_ep_ctx(xhci, in_ctx, ep_index);
1203 		ep_ctx->ep_info2 &= cpu_to_le32(~MAX_PACKET_MASK);
1204 		ep_ctx->ep_info2 |= cpu_to_le32(MAX_PACKET(max_packet_size));
1205 
1206 		/* Set up the input context flags for the command */
1207 		/* FIXME: This won't work if a non-default control endpoint
1208 		 * changes max packet sizes.
1209 		 */
1210 		ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
1211 		ctrl_ctx->add_flags = cpu_to_le32(EP0_FLAG);
1212 		ctrl_ctx->drop_flags = 0;
1213 
1214 		xhci_dbg(xhci, "Slot %d input context\n", slot_id);
1215 		xhci_dbg_ctx(xhci, in_ctx, ep_index);
1216 		xhci_dbg(xhci, "Slot %d output context\n", slot_id);
1217 		xhci_dbg_ctx(xhci, out_ctx, ep_index);
1218 
1219 		ret = xhci_configure_endpoint(xhci, urb->dev, NULL,
1220 				true, false);
1221 
1222 		/* Clean up the input context for later use by bandwidth
1223 		 * functions.
1224 		 */
1225 		ctrl_ctx->add_flags = cpu_to_le32(SLOT_FLAG);
1226 	}
1227 	return ret;
1228 }
1229 
1230 /*
1231  * non-error returns are a promise to giveback() the urb later
1232  * we drop ownership so next owner (or urb unlink) can get it
1233  */
1234 int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
1235 {
1236 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
1237 	struct xhci_td *buffer;
1238 	unsigned long flags;
1239 	int ret = 0;
1240 	unsigned int slot_id, ep_index;
1241 	struct urb_priv	*urb_priv;
1242 	int size, i;
1243 
1244 	if (!urb || xhci_check_args(hcd, urb->dev, urb->ep,
1245 					true, true, __func__) <= 0)
1246 		return -EINVAL;
1247 
1248 	slot_id = urb->dev->slot_id;
1249 	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
1250 
1251 	if (!HCD_HW_ACCESSIBLE(hcd)) {
1252 		if (!in_interrupt())
1253 			xhci_dbg(xhci, "urb submitted during PCI suspend\n");
1254 		ret = -ESHUTDOWN;
1255 		goto exit;
1256 	}
1257 
1258 	if (usb_endpoint_xfer_isoc(&urb->ep->desc))
1259 		size = urb->number_of_packets;
1260 	else
1261 		size = 1;
1262 
1263 	urb_priv = kzalloc(sizeof(struct urb_priv) +
1264 				  size * sizeof(struct xhci_td *), mem_flags);
1265 	if (!urb_priv)
1266 		return -ENOMEM;
1267 
1268 	buffer = kzalloc(size * sizeof(struct xhci_td), mem_flags);
1269 	if (!buffer) {
1270 		kfree(urb_priv);
1271 		return -ENOMEM;
1272 	}
1273 
1274 	for (i = 0; i < size; i++) {
1275 		urb_priv->td[i] = buffer;
1276 		buffer++;
1277 	}
1278 
1279 	urb_priv->length = size;
1280 	urb_priv->td_cnt = 0;
1281 	urb->hcpriv = urb_priv;
1282 
1283 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1284 		/* Check to see if the max packet size for the default control
1285 		 * endpoint changed during FS device enumeration
1286 		 */
1287 		if (urb->dev->speed == USB_SPEED_FULL) {
1288 			ret = xhci_check_maxpacket(xhci, slot_id,
1289 					ep_index, urb);
1290 			if (ret < 0) {
1291 				xhci_urb_free_priv(xhci, urb_priv);
1292 				urb->hcpriv = NULL;
1293 				return ret;
1294 			}
1295 		}
1296 
1297 		/* We have a spinlock and interrupts disabled, so we must pass
1298 		 * atomic context to this function, which may allocate memory.
1299 		 */
1300 		spin_lock_irqsave(&xhci->lock, flags);
1301 		if (xhci->xhc_state & XHCI_STATE_DYING)
1302 			goto dying;
1303 		ret = xhci_queue_ctrl_tx(xhci, GFP_ATOMIC, urb,
1304 				slot_id, ep_index);
1305 		if (ret)
1306 			goto free_priv;
1307 		spin_unlock_irqrestore(&xhci->lock, flags);
1308 	} else if (usb_endpoint_xfer_bulk(&urb->ep->desc)) {
1309 		spin_lock_irqsave(&xhci->lock, flags);
1310 		if (xhci->xhc_state & XHCI_STATE_DYING)
1311 			goto dying;
1312 		if (xhci->devs[slot_id]->eps[ep_index].ep_state &
1313 				EP_GETTING_STREAMS) {
1314 			xhci_warn(xhci, "WARN: Can't enqueue URB while bulk ep "
1315 					"is transitioning to using streams.\n");
1316 			ret = -EINVAL;
1317 		} else if (xhci->devs[slot_id]->eps[ep_index].ep_state &
1318 				EP_GETTING_NO_STREAMS) {
1319 			xhci_warn(xhci, "WARN: Can't enqueue URB while bulk ep "
1320 					"is transitioning to "
1321 					"not having streams.\n");
1322 			ret = -EINVAL;
1323 		} else {
1324 			ret = xhci_queue_bulk_tx(xhci, GFP_ATOMIC, urb,
1325 					slot_id, ep_index);
1326 		}
1327 		if (ret)
1328 			goto free_priv;
1329 		spin_unlock_irqrestore(&xhci->lock, flags);
1330 	} else if (usb_endpoint_xfer_int(&urb->ep->desc)) {
1331 		spin_lock_irqsave(&xhci->lock, flags);
1332 		if (xhci->xhc_state & XHCI_STATE_DYING)
1333 			goto dying;
1334 		ret = xhci_queue_intr_tx(xhci, GFP_ATOMIC, urb,
1335 				slot_id, ep_index);
1336 		if (ret)
1337 			goto free_priv;
1338 		spin_unlock_irqrestore(&xhci->lock, flags);
1339 	} else {
1340 		spin_lock_irqsave(&xhci->lock, flags);
1341 		if (xhci->xhc_state & XHCI_STATE_DYING)
1342 			goto dying;
1343 		ret = xhci_queue_isoc_tx_prepare(xhci, GFP_ATOMIC, urb,
1344 				slot_id, ep_index);
1345 		if (ret)
1346 			goto free_priv;
1347 		spin_unlock_irqrestore(&xhci->lock, flags);
1348 	}
1349 exit:
1350 	return ret;
1351 dying:
1352 	xhci_dbg(xhci, "Ep 0x%x: URB %p submitted for "
1353 			"non-responsive xHCI host.\n",
1354 			urb->ep->desc.bEndpointAddress, urb);
1355 	ret = -ESHUTDOWN;
1356 free_priv:
1357 	xhci_urb_free_priv(xhci, urb_priv);
1358 	urb->hcpriv = NULL;
1359 	spin_unlock_irqrestore(&xhci->lock, flags);
1360 	return ret;
1361 }
1362 
1363 /* Get the right ring for the given URB.
1364  * If the endpoint supports streams, boundary check the URB's stream ID.
1365  * If the endpoint doesn't support streams, return the singular endpoint ring.
1366  */
1367 static struct xhci_ring *xhci_urb_to_transfer_ring(struct xhci_hcd *xhci,
1368 		struct urb *urb)
1369 {
1370 	unsigned int slot_id;
1371 	unsigned int ep_index;
1372 	unsigned int stream_id;
1373 	struct xhci_virt_ep *ep;
1374 
1375 	slot_id = urb->dev->slot_id;
1376 	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
1377 	stream_id = urb->stream_id;
1378 	ep = &xhci->devs[slot_id]->eps[ep_index];
1379 	/* Common case: no streams */
1380 	if (!(ep->ep_state & EP_HAS_STREAMS))
1381 		return ep->ring;
1382 
1383 	if (stream_id == 0) {
1384 		xhci_warn(xhci,
1385 				"WARN: Slot ID %u, ep index %u has streams, "
1386 				"but URB has no stream ID.\n",
1387 				slot_id, ep_index);
1388 		return NULL;
1389 	}
1390 
1391 	if (stream_id < ep->stream_info->num_streams)
1392 		return ep->stream_info->stream_rings[stream_id];
1393 
1394 	xhci_warn(xhci,
1395 			"WARN: Slot ID %u, ep index %u has "
1396 			"stream IDs 1 to %u allocated, "
1397 			"but stream ID %u is requested.\n",
1398 			slot_id, ep_index,
1399 			ep->stream_info->num_streams - 1,
1400 			stream_id);
1401 	return NULL;
1402 }
1403 
1404 /*
1405  * Remove the URB's TD from the endpoint ring.  This may cause the HC to stop
1406  * USB transfers, potentially stopping in the middle of a TRB buffer.  The HC
1407  * should pick up where it left off in the TD, unless a Set Transfer Ring
1408  * Dequeue Pointer is issued.
1409  *
1410  * The TRBs that make up the buffers for the canceled URB will be "removed" from
1411  * the ring.  Since the ring is a contiguous structure, they can't be physically
1412  * removed.  Instead, there are two options:
1413  *
1414  *  1) If the HC is in the middle of processing the URB to be canceled, we
1415  *     simply move the ring's dequeue pointer past those TRBs using the Set
1416  *     Transfer Ring Dequeue Pointer command.  This will be the common case,
1417  *     when drivers timeout on the last submitted URB and attempt to cancel.
1418  *
1419  *  2) If the HC is in the middle of a different TD, we turn the TRBs into a
1420  *     series of 1-TRB transfer no-op TDs.  (No-ops shouldn't be chained.)  The
1421  *     HC will need to invalidate the any TRBs it has cached after the stop
1422  *     endpoint command, as noted in the xHCI 0.95 errata.
1423  *
1424  *  3) The TD may have completed by the time the Stop Endpoint Command
1425  *     completes, so software needs to handle that case too.
1426  *
1427  * This function should protect against the TD enqueueing code ringing the
1428  * doorbell while this code is waiting for a Stop Endpoint command to complete.
1429  * It also needs to account for multiple cancellations on happening at the same
1430  * time for the same endpoint.
1431  *
1432  * Note that this function can be called in any context, or so says
1433  * usb_hcd_unlink_urb()
1434  */
1435 int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1436 {
1437 	unsigned long flags;
1438 	int ret, i;
1439 	u32 temp;
1440 	struct xhci_hcd *xhci;
1441 	struct urb_priv	*urb_priv;
1442 	struct xhci_td *td;
1443 	unsigned int ep_index;
1444 	struct xhci_ring *ep_ring;
1445 	struct xhci_virt_ep *ep;
1446 
1447 	xhci = hcd_to_xhci(hcd);
1448 	spin_lock_irqsave(&xhci->lock, flags);
1449 	/* Make sure the URB hasn't completed or been unlinked already */
1450 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
1451 	if (ret || !urb->hcpriv)
1452 		goto done;
1453 	temp = xhci_readl(xhci, &xhci->op_regs->status);
1454 	if (temp == 0xffffffff || (xhci->xhc_state & XHCI_STATE_HALTED)) {
1455 		xhci_dbg(xhci, "HW died, freeing TD.\n");
1456 		urb_priv = urb->hcpriv;
1457 		for (i = urb_priv->td_cnt; i < urb_priv->length; i++) {
1458 			td = urb_priv->td[i];
1459 			if (!list_empty(&td->td_list))
1460 				list_del_init(&td->td_list);
1461 			if (!list_empty(&td->cancelled_td_list))
1462 				list_del_init(&td->cancelled_td_list);
1463 		}
1464 
1465 		usb_hcd_unlink_urb_from_ep(hcd, urb);
1466 		spin_unlock_irqrestore(&xhci->lock, flags);
1467 		usb_hcd_giveback_urb(hcd, urb, -ESHUTDOWN);
1468 		xhci_urb_free_priv(xhci, urb_priv);
1469 		return ret;
1470 	}
1471 	if ((xhci->xhc_state & XHCI_STATE_DYING) ||
1472 			(xhci->xhc_state & XHCI_STATE_HALTED)) {
1473 		xhci_dbg(xhci, "Ep 0x%x: URB %p to be canceled on "
1474 				"non-responsive xHCI host.\n",
1475 				urb->ep->desc.bEndpointAddress, urb);
1476 		/* Let the stop endpoint command watchdog timer (which set this
1477 		 * state) finish cleaning up the endpoint TD lists.  We must
1478 		 * have caught it in the middle of dropping a lock and giving
1479 		 * back an URB.
1480 		 */
1481 		goto done;
1482 	}
1483 
1484 	ep_index = xhci_get_endpoint_index(&urb->ep->desc);
1485 	ep = &xhci->devs[urb->dev->slot_id]->eps[ep_index];
1486 	ep_ring = xhci_urb_to_transfer_ring(xhci, urb);
1487 	if (!ep_ring) {
1488 		ret = -EINVAL;
1489 		goto done;
1490 	}
1491 
1492 	urb_priv = urb->hcpriv;
1493 	i = urb_priv->td_cnt;
1494 	if (i < urb_priv->length)
1495 		xhci_dbg(xhci, "Cancel URB %p, dev %s, ep 0x%x, "
1496 				"starting at offset 0x%llx\n",
1497 				urb, urb->dev->devpath,
1498 				urb->ep->desc.bEndpointAddress,
1499 				(unsigned long long) xhci_trb_virt_to_dma(
1500 					urb_priv->td[i]->start_seg,
1501 					urb_priv->td[i]->first_trb));
1502 
1503 	for (; i < urb_priv->length; i++) {
1504 		td = urb_priv->td[i];
1505 		list_add_tail(&td->cancelled_td_list, &ep->cancelled_td_list);
1506 	}
1507 
1508 	/* Queue a stop endpoint command, but only if this is
1509 	 * the first cancellation to be handled.
1510 	 */
1511 	if (!(ep->ep_state & EP_HALT_PENDING)) {
1512 		ep->ep_state |= EP_HALT_PENDING;
1513 		ep->stop_cmds_pending++;
1514 		ep->stop_cmd_timer.expires = jiffies +
1515 			XHCI_STOP_EP_CMD_TIMEOUT * HZ;
1516 		add_timer(&ep->stop_cmd_timer);
1517 		xhci_queue_stop_endpoint(xhci, urb->dev->slot_id, ep_index, 0);
1518 		xhci_ring_cmd_db(xhci);
1519 	}
1520 done:
1521 	spin_unlock_irqrestore(&xhci->lock, flags);
1522 	return ret;
1523 }
1524 
1525 /* Drop an endpoint from a new bandwidth configuration for this device.
1526  * Only one call to this function is allowed per endpoint before
1527  * check_bandwidth() or reset_bandwidth() must be called.
1528  * A call to xhci_drop_endpoint() followed by a call to xhci_add_endpoint() will
1529  * add the endpoint to the schedule with possibly new parameters denoted by a
1530  * different endpoint descriptor in usb_host_endpoint.
1531  * A call to xhci_add_endpoint() followed by a call to xhci_drop_endpoint() is
1532  * not allowed.
1533  *
1534  * The USB core will not allow URBs to be queued to an endpoint that is being
1535  * disabled, so there's no need for mutual exclusion to protect
1536  * the xhci->devs[slot_id] structure.
1537  */
1538 int xhci_drop_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
1539 		struct usb_host_endpoint *ep)
1540 {
1541 	struct xhci_hcd *xhci;
1542 	struct xhci_container_ctx *in_ctx, *out_ctx;
1543 	struct xhci_input_control_ctx *ctrl_ctx;
1544 	struct xhci_slot_ctx *slot_ctx;
1545 	unsigned int last_ctx;
1546 	unsigned int ep_index;
1547 	struct xhci_ep_ctx *ep_ctx;
1548 	u32 drop_flag;
1549 	u32 new_add_flags, new_drop_flags, new_slot_info;
1550 	int ret;
1551 
1552 	ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
1553 	if (ret <= 0)
1554 		return ret;
1555 	xhci = hcd_to_xhci(hcd);
1556 	if (xhci->xhc_state & XHCI_STATE_DYING)
1557 		return -ENODEV;
1558 
1559 	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
1560 	drop_flag = xhci_get_endpoint_flag(&ep->desc);
1561 	if (drop_flag == SLOT_FLAG || drop_flag == EP0_FLAG) {
1562 		xhci_dbg(xhci, "xHCI %s - can't drop slot or ep 0 %#x\n",
1563 				__func__, drop_flag);
1564 		return 0;
1565 	}
1566 
1567 	in_ctx = xhci->devs[udev->slot_id]->in_ctx;
1568 	out_ctx = xhci->devs[udev->slot_id]->out_ctx;
1569 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
1570 	ep_index = xhci_get_endpoint_index(&ep->desc);
1571 	ep_ctx = xhci_get_ep_ctx(xhci, out_ctx, ep_index);
1572 	/* If the HC already knows the endpoint is disabled,
1573 	 * or the HCD has noted it is disabled, ignore this request
1574 	 */
1575 	if (((ep_ctx->ep_info & cpu_to_le32(EP_STATE_MASK)) ==
1576 	     cpu_to_le32(EP_STATE_DISABLED)) ||
1577 	    le32_to_cpu(ctrl_ctx->drop_flags) &
1578 	    xhci_get_endpoint_flag(&ep->desc)) {
1579 		xhci_warn(xhci, "xHCI %s called with disabled ep %p\n",
1580 				__func__, ep);
1581 		return 0;
1582 	}
1583 
1584 	ctrl_ctx->drop_flags |= cpu_to_le32(drop_flag);
1585 	new_drop_flags = le32_to_cpu(ctrl_ctx->drop_flags);
1586 
1587 	ctrl_ctx->add_flags &= cpu_to_le32(~drop_flag);
1588 	new_add_flags = le32_to_cpu(ctrl_ctx->add_flags);
1589 
1590 	last_ctx = xhci_last_valid_endpoint(le32_to_cpu(ctrl_ctx->add_flags));
1591 	slot_ctx = xhci_get_slot_ctx(xhci, in_ctx);
1592 	/* Update the last valid endpoint context, if we deleted the last one */
1593 	if ((le32_to_cpu(slot_ctx->dev_info) & LAST_CTX_MASK) >
1594 	    LAST_CTX(last_ctx)) {
1595 		slot_ctx->dev_info &= cpu_to_le32(~LAST_CTX_MASK);
1596 		slot_ctx->dev_info |= cpu_to_le32(LAST_CTX(last_ctx));
1597 	}
1598 	new_slot_info = le32_to_cpu(slot_ctx->dev_info);
1599 
1600 	xhci_endpoint_zero(xhci, xhci->devs[udev->slot_id], ep);
1601 
1602 	xhci_dbg(xhci, "drop ep 0x%x, slot id %d, new drop flags = %#x, new add flags = %#x, new slot info = %#x\n",
1603 			(unsigned int) ep->desc.bEndpointAddress,
1604 			udev->slot_id,
1605 			(unsigned int) new_drop_flags,
1606 			(unsigned int) new_add_flags,
1607 			(unsigned int) new_slot_info);
1608 	return 0;
1609 }
1610 
1611 /* Add an endpoint to a new possible bandwidth configuration for this device.
1612  * Only one call to this function is allowed per endpoint before
1613  * check_bandwidth() or reset_bandwidth() must be called.
1614  * A call to xhci_drop_endpoint() followed by a call to xhci_add_endpoint() will
1615  * add the endpoint to the schedule with possibly new parameters denoted by a
1616  * different endpoint descriptor in usb_host_endpoint.
1617  * A call to xhci_add_endpoint() followed by a call to xhci_drop_endpoint() is
1618  * not allowed.
1619  *
1620  * The USB core will not allow URBs to be queued to an endpoint until the
1621  * configuration or alt setting is installed in the device, so there's no need
1622  * for mutual exclusion to protect the xhci->devs[slot_id] structure.
1623  */
1624 int xhci_add_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
1625 		struct usb_host_endpoint *ep)
1626 {
1627 	struct xhci_hcd *xhci;
1628 	struct xhci_container_ctx *in_ctx, *out_ctx;
1629 	unsigned int ep_index;
1630 	struct xhci_slot_ctx *slot_ctx;
1631 	struct xhci_input_control_ctx *ctrl_ctx;
1632 	u32 added_ctxs;
1633 	unsigned int last_ctx;
1634 	u32 new_add_flags, new_drop_flags, new_slot_info;
1635 	struct xhci_virt_device *virt_dev;
1636 	int ret = 0;
1637 
1638 	ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
1639 	if (ret <= 0) {
1640 		/* So we won't queue a reset ep command for a root hub */
1641 		ep->hcpriv = NULL;
1642 		return ret;
1643 	}
1644 	xhci = hcd_to_xhci(hcd);
1645 	if (xhci->xhc_state & XHCI_STATE_DYING)
1646 		return -ENODEV;
1647 
1648 	added_ctxs = xhci_get_endpoint_flag(&ep->desc);
1649 	last_ctx = xhci_last_valid_endpoint(added_ctxs);
1650 	if (added_ctxs == SLOT_FLAG || added_ctxs == EP0_FLAG) {
1651 		/* FIXME when we have to issue an evaluate endpoint command to
1652 		 * deal with ep0 max packet size changing once we get the
1653 		 * descriptors
1654 		 */
1655 		xhci_dbg(xhci, "xHCI %s - can't add slot or ep 0 %#x\n",
1656 				__func__, added_ctxs);
1657 		return 0;
1658 	}
1659 
1660 	virt_dev = xhci->devs[udev->slot_id];
1661 	in_ctx = virt_dev->in_ctx;
1662 	out_ctx = virt_dev->out_ctx;
1663 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
1664 	ep_index = xhci_get_endpoint_index(&ep->desc);
1665 
1666 	/* If this endpoint is already in use, and the upper layers are trying
1667 	 * to add it again without dropping it, reject the addition.
1668 	 */
1669 	if (virt_dev->eps[ep_index].ring &&
1670 			!(le32_to_cpu(ctrl_ctx->drop_flags) &
1671 				xhci_get_endpoint_flag(&ep->desc))) {
1672 		xhci_warn(xhci, "Trying to add endpoint 0x%x "
1673 				"without dropping it.\n",
1674 				(unsigned int) ep->desc.bEndpointAddress);
1675 		return -EINVAL;
1676 	}
1677 
1678 	/* If the HCD has already noted the endpoint is enabled,
1679 	 * ignore this request.
1680 	 */
1681 	if (le32_to_cpu(ctrl_ctx->add_flags) &
1682 	    xhci_get_endpoint_flag(&ep->desc)) {
1683 		xhci_warn(xhci, "xHCI %s called with enabled ep %p\n",
1684 				__func__, ep);
1685 		return 0;
1686 	}
1687 
1688 	/*
1689 	 * Configuration and alternate setting changes must be done in
1690 	 * process context, not interrupt context (or so documenation
1691 	 * for usb_set_interface() and usb_set_configuration() claim).
1692 	 */
1693 	if (xhci_endpoint_init(xhci, virt_dev, udev, ep, GFP_NOIO) < 0) {
1694 		dev_dbg(&udev->dev, "%s - could not initialize ep %#x\n",
1695 				__func__, ep->desc.bEndpointAddress);
1696 		return -ENOMEM;
1697 	}
1698 
1699 	ctrl_ctx->add_flags |= cpu_to_le32(added_ctxs);
1700 	new_add_flags = le32_to_cpu(ctrl_ctx->add_flags);
1701 
1702 	/* If xhci_endpoint_disable() was called for this endpoint, but the
1703 	 * xHC hasn't been notified yet through the check_bandwidth() call,
1704 	 * this re-adds a new state for the endpoint from the new endpoint
1705 	 * descriptors.  We must drop and re-add this endpoint, so we leave the
1706 	 * drop flags alone.
1707 	 */
1708 	new_drop_flags = le32_to_cpu(ctrl_ctx->drop_flags);
1709 
1710 	slot_ctx = xhci_get_slot_ctx(xhci, in_ctx);
1711 	/* Update the last valid endpoint context, if we just added one past */
1712 	if ((le32_to_cpu(slot_ctx->dev_info) & LAST_CTX_MASK) <
1713 	    LAST_CTX(last_ctx)) {
1714 		slot_ctx->dev_info &= cpu_to_le32(~LAST_CTX_MASK);
1715 		slot_ctx->dev_info |= cpu_to_le32(LAST_CTX(last_ctx));
1716 	}
1717 	new_slot_info = le32_to_cpu(slot_ctx->dev_info);
1718 
1719 	/* Store the usb_device pointer for later use */
1720 	ep->hcpriv = udev;
1721 
1722 	xhci_dbg(xhci, "add ep 0x%x, slot id %d, new drop flags = %#x, new add flags = %#x, new slot info = %#x\n",
1723 			(unsigned int) ep->desc.bEndpointAddress,
1724 			udev->slot_id,
1725 			(unsigned int) new_drop_flags,
1726 			(unsigned int) new_add_flags,
1727 			(unsigned int) new_slot_info);
1728 	return 0;
1729 }
1730 
1731 static void xhci_zero_in_ctx(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev)
1732 {
1733 	struct xhci_input_control_ctx *ctrl_ctx;
1734 	struct xhci_ep_ctx *ep_ctx;
1735 	struct xhci_slot_ctx *slot_ctx;
1736 	int i;
1737 
1738 	/* When a device's add flag and drop flag are zero, any subsequent
1739 	 * configure endpoint command will leave that endpoint's state
1740 	 * untouched.  Make sure we don't leave any old state in the input
1741 	 * endpoint contexts.
1742 	 */
1743 	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
1744 	ctrl_ctx->drop_flags = 0;
1745 	ctrl_ctx->add_flags = 0;
1746 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
1747 	slot_ctx->dev_info &= cpu_to_le32(~LAST_CTX_MASK);
1748 	/* Endpoint 0 is always valid */
1749 	slot_ctx->dev_info |= cpu_to_le32(LAST_CTX(1));
1750 	for (i = 1; i < 31; ++i) {
1751 		ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, i);
1752 		ep_ctx->ep_info = 0;
1753 		ep_ctx->ep_info2 = 0;
1754 		ep_ctx->deq = 0;
1755 		ep_ctx->tx_info = 0;
1756 	}
1757 }
1758 
1759 static int xhci_configure_endpoint_result(struct xhci_hcd *xhci,
1760 		struct usb_device *udev, u32 *cmd_status)
1761 {
1762 	int ret;
1763 
1764 	switch (*cmd_status) {
1765 	case COMP_ENOMEM:
1766 		dev_warn(&udev->dev, "Not enough host controller resources "
1767 				"for new device state.\n");
1768 		ret = -ENOMEM;
1769 		/* FIXME: can we allocate more resources for the HC? */
1770 		break;
1771 	case COMP_BW_ERR:
1772 	case COMP_2ND_BW_ERR:
1773 		dev_warn(&udev->dev, "Not enough bandwidth "
1774 				"for new device state.\n");
1775 		ret = -ENOSPC;
1776 		/* FIXME: can we go back to the old state? */
1777 		break;
1778 	case COMP_TRB_ERR:
1779 		/* the HCD set up something wrong */
1780 		dev_warn(&udev->dev, "ERROR: Endpoint drop flag = 0, "
1781 				"add flag = 1, "
1782 				"and endpoint is not disabled.\n");
1783 		ret = -EINVAL;
1784 		break;
1785 	case COMP_DEV_ERR:
1786 		dev_warn(&udev->dev, "ERROR: Incompatible device for endpoint "
1787 				"configure command.\n");
1788 		ret = -ENODEV;
1789 		break;
1790 	case COMP_SUCCESS:
1791 		dev_dbg(&udev->dev, "Successful Endpoint Configure command\n");
1792 		ret = 0;
1793 		break;
1794 	default:
1795 		xhci_err(xhci, "ERROR: unexpected command completion "
1796 				"code 0x%x.\n", *cmd_status);
1797 		ret = -EINVAL;
1798 		break;
1799 	}
1800 	return ret;
1801 }
1802 
1803 static int xhci_evaluate_context_result(struct xhci_hcd *xhci,
1804 		struct usb_device *udev, u32 *cmd_status)
1805 {
1806 	int ret;
1807 	struct xhci_virt_device *virt_dev = xhci->devs[udev->slot_id];
1808 
1809 	switch (*cmd_status) {
1810 	case COMP_EINVAL:
1811 		dev_warn(&udev->dev, "WARN: xHCI driver setup invalid evaluate "
1812 				"context command.\n");
1813 		ret = -EINVAL;
1814 		break;
1815 	case COMP_EBADSLT:
1816 		dev_warn(&udev->dev, "WARN: slot not enabled for"
1817 				"evaluate context command.\n");
1818 		ret = -EINVAL;
1819 		break;
1820 	case COMP_CTX_STATE:
1821 		dev_warn(&udev->dev, "WARN: invalid context state for "
1822 				"evaluate context command.\n");
1823 		xhci_dbg_ctx(xhci, virt_dev->out_ctx, 1);
1824 		ret = -EINVAL;
1825 		break;
1826 	case COMP_DEV_ERR:
1827 		dev_warn(&udev->dev, "ERROR: Incompatible device for evaluate "
1828 				"context command.\n");
1829 		ret = -ENODEV;
1830 		break;
1831 	case COMP_MEL_ERR:
1832 		/* Max Exit Latency too large error */
1833 		dev_warn(&udev->dev, "WARN: Max Exit Latency too large\n");
1834 		ret = -EINVAL;
1835 		break;
1836 	case COMP_SUCCESS:
1837 		dev_dbg(&udev->dev, "Successful evaluate context command\n");
1838 		ret = 0;
1839 		break;
1840 	default:
1841 		xhci_err(xhci, "ERROR: unexpected command completion "
1842 				"code 0x%x.\n", *cmd_status);
1843 		ret = -EINVAL;
1844 		break;
1845 	}
1846 	return ret;
1847 }
1848 
1849 static u32 xhci_count_num_new_endpoints(struct xhci_hcd *xhci,
1850 		struct xhci_container_ctx *in_ctx)
1851 {
1852 	struct xhci_input_control_ctx *ctrl_ctx;
1853 	u32 valid_add_flags;
1854 	u32 valid_drop_flags;
1855 
1856 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
1857 	/* Ignore the slot flag (bit 0), and the default control endpoint flag
1858 	 * (bit 1).  The default control endpoint is added during the Address
1859 	 * Device command and is never removed until the slot is disabled.
1860 	 */
1861 	valid_add_flags = ctrl_ctx->add_flags >> 2;
1862 	valid_drop_flags = ctrl_ctx->drop_flags >> 2;
1863 
1864 	/* Use hweight32 to count the number of ones in the add flags, or
1865 	 * number of endpoints added.  Don't count endpoints that are changed
1866 	 * (both added and dropped).
1867 	 */
1868 	return hweight32(valid_add_flags) -
1869 		hweight32(valid_add_flags & valid_drop_flags);
1870 }
1871 
1872 static unsigned int xhci_count_num_dropped_endpoints(struct xhci_hcd *xhci,
1873 		struct xhci_container_ctx *in_ctx)
1874 {
1875 	struct xhci_input_control_ctx *ctrl_ctx;
1876 	u32 valid_add_flags;
1877 	u32 valid_drop_flags;
1878 
1879 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
1880 	valid_add_flags = ctrl_ctx->add_flags >> 2;
1881 	valid_drop_flags = ctrl_ctx->drop_flags >> 2;
1882 
1883 	return hweight32(valid_drop_flags) -
1884 		hweight32(valid_add_flags & valid_drop_flags);
1885 }
1886 
1887 /*
1888  * We need to reserve the new number of endpoints before the configure endpoint
1889  * command completes.  We can't subtract the dropped endpoints from the number
1890  * of active endpoints until the command completes because we can oversubscribe
1891  * the host in this case:
1892  *
1893  *  - the first configure endpoint command drops more endpoints than it adds
1894  *  - a second configure endpoint command that adds more endpoints is queued
1895  *  - the first configure endpoint command fails, so the config is unchanged
1896  *  - the second command may succeed, even though there isn't enough resources
1897  *
1898  * Must be called with xhci->lock held.
1899  */
1900 static int xhci_reserve_host_resources(struct xhci_hcd *xhci,
1901 		struct xhci_container_ctx *in_ctx)
1902 {
1903 	u32 added_eps;
1904 
1905 	added_eps = xhci_count_num_new_endpoints(xhci, in_ctx);
1906 	if (xhci->num_active_eps + added_eps > xhci->limit_active_eps) {
1907 		xhci_dbg(xhci, "Not enough ep ctxs: "
1908 				"%u active, need to add %u, limit is %u.\n",
1909 				xhci->num_active_eps, added_eps,
1910 				xhci->limit_active_eps);
1911 		return -ENOMEM;
1912 	}
1913 	xhci->num_active_eps += added_eps;
1914 	xhci_dbg(xhci, "Adding %u ep ctxs, %u now active.\n", added_eps,
1915 			xhci->num_active_eps);
1916 	return 0;
1917 }
1918 
1919 /*
1920  * The configure endpoint was failed by the xHC for some other reason, so we
1921  * need to revert the resources that failed configuration would have used.
1922  *
1923  * Must be called with xhci->lock held.
1924  */
1925 static void xhci_free_host_resources(struct xhci_hcd *xhci,
1926 		struct xhci_container_ctx *in_ctx)
1927 {
1928 	u32 num_failed_eps;
1929 
1930 	num_failed_eps = xhci_count_num_new_endpoints(xhci, in_ctx);
1931 	xhci->num_active_eps -= num_failed_eps;
1932 	xhci_dbg(xhci, "Removing %u failed ep ctxs, %u now active.\n",
1933 			num_failed_eps,
1934 			xhci->num_active_eps);
1935 }
1936 
1937 /*
1938  * Now that the command has completed, clean up the active endpoint count by
1939  * subtracting out the endpoints that were dropped (but not changed).
1940  *
1941  * Must be called with xhci->lock held.
1942  */
1943 static void xhci_finish_resource_reservation(struct xhci_hcd *xhci,
1944 		struct xhci_container_ctx *in_ctx)
1945 {
1946 	u32 num_dropped_eps;
1947 
1948 	num_dropped_eps = xhci_count_num_dropped_endpoints(xhci, in_ctx);
1949 	xhci->num_active_eps -= num_dropped_eps;
1950 	if (num_dropped_eps)
1951 		xhci_dbg(xhci, "Removing %u dropped ep ctxs, %u now active.\n",
1952 				num_dropped_eps,
1953 				xhci->num_active_eps);
1954 }
1955 
1956 static unsigned int xhci_get_block_size(struct usb_device *udev)
1957 {
1958 	switch (udev->speed) {
1959 	case USB_SPEED_LOW:
1960 	case USB_SPEED_FULL:
1961 		return FS_BLOCK;
1962 	case USB_SPEED_HIGH:
1963 		return HS_BLOCK;
1964 	case USB_SPEED_SUPER:
1965 		return SS_BLOCK;
1966 	case USB_SPEED_UNKNOWN:
1967 	case USB_SPEED_WIRELESS:
1968 	default:
1969 		/* Should never happen */
1970 		return 1;
1971 	}
1972 }
1973 
1974 static unsigned int
1975 xhci_get_largest_overhead(struct xhci_interval_bw *interval_bw)
1976 {
1977 	if (interval_bw->overhead[LS_OVERHEAD_TYPE])
1978 		return LS_OVERHEAD;
1979 	if (interval_bw->overhead[FS_OVERHEAD_TYPE])
1980 		return FS_OVERHEAD;
1981 	return HS_OVERHEAD;
1982 }
1983 
1984 /* If we are changing a LS/FS device under a HS hub,
1985  * make sure (if we are activating a new TT) that the HS bus has enough
1986  * bandwidth for this new TT.
1987  */
1988 static int xhci_check_tt_bw_table(struct xhci_hcd *xhci,
1989 		struct xhci_virt_device *virt_dev,
1990 		int old_active_eps)
1991 {
1992 	struct xhci_interval_bw_table *bw_table;
1993 	struct xhci_tt_bw_info *tt_info;
1994 
1995 	/* Find the bandwidth table for the root port this TT is attached to. */
1996 	bw_table = &xhci->rh_bw[virt_dev->real_port - 1].bw_table;
1997 	tt_info = virt_dev->tt_info;
1998 	/* If this TT already had active endpoints, the bandwidth for this TT
1999 	 * has already been added.  Removing all periodic endpoints (and thus
2000 	 * making the TT enactive) will only decrease the bandwidth used.
2001 	 */
2002 	if (old_active_eps)
2003 		return 0;
2004 	if (old_active_eps == 0 && tt_info->active_eps != 0) {
2005 		if (bw_table->bw_used + TT_HS_OVERHEAD > HS_BW_LIMIT)
2006 			return -ENOMEM;
2007 		return 0;
2008 	}
2009 	/* Not sure why we would have no new active endpoints...
2010 	 *
2011 	 * Maybe because of an Evaluate Context change for a hub update or a
2012 	 * control endpoint 0 max packet size change?
2013 	 * FIXME: skip the bandwidth calculation in that case.
2014 	 */
2015 	return 0;
2016 }
2017 
2018 static int xhci_check_ss_bw(struct xhci_hcd *xhci,
2019 		struct xhci_virt_device *virt_dev)
2020 {
2021 	unsigned int bw_reserved;
2022 
2023 	bw_reserved = DIV_ROUND_UP(SS_BW_RESERVED*SS_BW_LIMIT_IN, 100);
2024 	if (virt_dev->bw_table->ss_bw_in > (SS_BW_LIMIT_IN - bw_reserved))
2025 		return -ENOMEM;
2026 
2027 	bw_reserved = DIV_ROUND_UP(SS_BW_RESERVED*SS_BW_LIMIT_OUT, 100);
2028 	if (virt_dev->bw_table->ss_bw_out > (SS_BW_LIMIT_OUT - bw_reserved))
2029 		return -ENOMEM;
2030 
2031 	return 0;
2032 }
2033 
2034 /*
2035  * This algorithm is a very conservative estimate of the worst-case scheduling
2036  * scenario for any one interval.  The hardware dynamically schedules the
2037  * packets, so we can't tell which microframe could be the limiting factor in
2038  * the bandwidth scheduling.  This only takes into account periodic endpoints.
2039  *
2040  * Obviously, we can't solve an NP complete problem to find the minimum worst
2041  * case scenario.  Instead, we come up with an estimate that is no less than
2042  * the worst case bandwidth used for any one microframe, but may be an
2043  * over-estimate.
2044  *
2045  * We walk the requirements for each endpoint by interval, starting with the
2046  * smallest interval, and place packets in the schedule where there is only one
2047  * possible way to schedule packets for that interval.  In order to simplify
2048  * this algorithm, we record the largest max packet size for each interval, and
2049  * assume all packets will be that size.
2050  *
2051  * For interval 0, we obviously must schedule all packets for each interval.
2052  * The bandwidth for interval 0 is just the amount of data to be transmitted
2053  * (the sum of all max ESIT payload sizes, plus any overhead per packet times
2054  * the number of packets).
2055  *
2056  * For interval 1, we have two possible microframes to schedule those packets
2057  * in.  For this algorithm, if we can schedule the same number of packets for
2058  * each possible scheduling opportunity (each microframe), we will do so.  The
2059  * remaining number of packets will be saved to be transmitted in the gaps in
2060  * the next interval's scheduling sequence.
2061  *
2062  * As we move those remaining packets to be scheduled with interval 2 packets,
2063  * we have to double the number of remaining packets to transmit.  This is
2064  * because the intervals are actually powers of 2, and we would be transmitting
2065  * the previous interval's packets twice in this interval.  We also have to be
2066  * sure that when we look at the largest max packet size for this interval, we
2067  * also look at the largest max packet size for the remaining packets and take
2068  * the greater of the two.
2069  *
2070  * The algorithm continues to evenly distribute packets in each scheduling
2071  * opportunity, and push the remaining packets out, until we get to the last
2072  * interval.  Then those packets and their associated overhead are just added
2073  * to the bandwidth used.
2074  */
2075 static int xhci_check_bw_table(struct xhci_hcd *xhci,
2076 		struct xhci_virt_device *virt_dev,
2077 		int old_active_eps)
2078 {
2079 	unsigned int bw_reserved;
2080 	unsigned int max_bandwidth;
2081 	unsigned int bw_used;
2082 	unsigned int block_size;
2083 	struct xhci_interval_bw_table *bw_table;
2084 	unsigned int packet_size = 0;
2085 	unsigned int overhead = 0;
2086 	unsigned int packets_transmitted = 0;
2087 	unsigned int packets_remaining = 0;
2088 	unsigned int i;
2089 
2090 	if (virt_dev->udev->speed == USB_SPEED_SUPER)
2091 		return xhci_check_ss_bw(xhci, virt_dev);
2092 
2093 	if (virt_dev->udev->speed == USB_SPEED_HIGH) {
2094 		max_bandwidth = HS_BW_LIMIT;
2095 		/* Convert percent of bus BW reserved to blocks reserved */
2096 		bw_reserved = DIV_ROUND_UP(HS_BW_RESERVED * max_bandwidth, 100);
2097 	} else {
2098 		max_bandwidth = FS_BW_LIMIT;
2099 		bw_reserved = DIV_ROUND_UP(FS_BW_RESERVED * max_bandwidth, 100);
2100 	}
2101 
2102 	bw_table = virt_dev->bw_table;
2103 	/* We need to translate the max packet size and max ESIT payloads into
2104 	 * the units the hardware uses.
2105 	 */
2106 	block_size = xhci_get_block_size(virt_dev->udev);
2107 
2108 	/* If we are manipulating a LS/FS device under a HS hub, double check
2109 	 * that the HS bus has enough bandwidth if we are activing a new TT.
2110 	 */
2111 	if (virt_dev->tt_info) {
2112 		xhci_dbg(xhci, "Recalculating BW for rootport %u\n",
2113 				virt_dev->real_port);
2114 		if (xhci_check_tt_bw_table(xhci, virt_dev, old_active_eps)) {
2115 			xhci_warn(xhci, "Not enough bandwidth on HS bus for "
2116 					"newly activated TT.\n");
2117 			return -ENOMEM;
2118 		}
2119 		xhci_dbg(xhci, "Recalculating BW for TT slot %u port %u\n",
2120 				virt_dev->tt_info->slot_id,
2121 				virt_dev->tt_info->ttport);
2122 	} else {
2123 		xhci_dbg(xhci, "Recalculating BW for rootport %u\n",
2124 				virt_dev->real_port);
2125 	}
2126 
2127 	/* Add in how much bandwidth will be used for interval zero, or the
2128 	 * rounded max ESIT payload + number of packets * largest overhead.
2129 	 */
2130 	bw_used = DIV_ROUND_UP(bw_table->interval0_esit_payload, block_size) +
2131 		bw_table->interval_bw[0].num_packets *
2132 		xhci_get_largest_overhead(&bw_table->interval_bw[0]);
2133 
2134 	for (i = 1; i < XHCI_MAX_INTERVAL; i++) {
2135 		unsigned int bw_added;
2136 		unsigned int largest_mps;
2137 		unsigned int interval_overhead;
2138 
2139 		/*
2140 		 * How many packets could we transmit in this interval?
2141 		 * If packets didn't fit in the previous interval, we will need
2142 		 * to transmit that many packets twice within this interval.
2143 		 */
2144 		packets_remaining = 2 * packets_remaining +
2145 			bw_table->interval_bw[i].num_packets;
2146 
2147 		/* Find the largest max packet size of this or the previous
2148 		 * interval.
2149 		 */
2150 		if (list_empty(&bw_table->interval_bw[i].endpoints))
2151 			largest_mps = 0;
2152 		else {
2153 			struct xhci_virt_ep *virt_ep;
2154 			struct list_head *ep_entry;
2155 
2156 			ep_entry = bw_table->interval_bw[i].endpoints.next;
2157 			virt_ep = list_entry(ep_entry,
2158 					struct xhci_virt_ep, bw_endpoint_list);
2159 			/* Convert to blocks, rounding up */
2160 			largest_mps = DIV_ROUND_UP(
2161 					virt_ep->bw_info.max_packet_size,
2162 					block_size);
2163 		}
2164 		if (largest_mps > packet_size)
2165 			packet_size = largest_mps;
2166 
2167 		/* Use the larger overhead of this or the previous interval. */
2168 		interval_overhead = xhci_get_largest_overhead(
2169 				&bw_table->interval_bw[i]);
2170 		if (interval_overhead > overhead)
2171 			overhead = interval_overhead;
2172 
2173 		/* How many packets can we evenly distribute across
2174 		 * (1 << (i + 1)) possible scheduling opportunities?
2175 		 */
2176 		packets_transmitted = packets_remaining >> (i + 1);
2177 
2178 		/* Add in the bandwidth used for those scheduled packets */
2179 		bw_added = packets_transmitted * (overhead + packet_size);
2180 
2181 		/* How many packets do we have remaining to transmit? */
2182 		packets_remaining = packets_remaining % (1 << (i + 1));
2183 
2184 		/* What largest max packet size should those packets have? */
2185 		/* If we've transmitted all packets, don't carry over the
2186 		 * largest packet size.
2187 		 */
2188 		if (packets_remaining == 0) {
2189 			packet_size = 0;
2190 			overhead = 0;
2191 		} else if (packets_transmitted > 0) {
2192 			/* Otherwise if we do have remaining packets, and we've
2193 			 * scheduled some packets in this interval, take the
2194 			 * largest max packet size from endpoints with this
2195 			 * interval.
2196 			 */
2197 			packet_size = largest_mps;
2198 			overhead = interval_overhead;
2199 		}
2200 		/* Otherwise carry over packet_size and overhead from the last
2201 		 * time we had a remainder.
2202 		 */
2203 		bw_used += bw_added;
2204 		if (bw_used > max_bandwidth) {
2205 			xhci_warn(xhci, "Not enough bandwidth. "
2206 					"Proposed: %u, Max: %u\n",
2207 				bw_used, max_bandwidth);
2208 			return -ENOMEM;
2209 		}
2210 	}
2211 	/*
2212 	 * Ok, we know we have some packets left over after even-handedly
2213 	 * scheduling interval 15.  We don't know which microframes they will
2214 	 * fit into, so we over-schedule and say they will be scheduled every
2215 	 * microframe.
2216 	 */
2217 	if (packets_remaining > 0)
2218 		bw_used += overhead + packet_size;
2219 
2220 	if (!virt_dev->tt_info && virt_dev->udev->speed == USB_SPEED_HIGH) {
2221 		unsigned int port_index = virt_dev->real_port - 1;
2222 
2223 		/* OK, we're manipulating a HS device attached to a
2224 		 * root port bandwidth domain.  Include the number of active TTs
2225 		 * in the bandwidth used.
2226 		 */
2227 		bw_used += TT_HS_OVERHEAD *
2228 			xhci->rh_bw[port_index].num_active_tts;
2229 	}
2230 
2231 	xhci_dbg(xhci, "Final bandwidth: %u, Limit: %u, Reserved: %u, "
2232 		"Available: %u " "percent\n",
2233 		bw_used, max_bandwidth, bw_reserved,
2234 		(max_bandwidth - bw_used - bw_reserved) * 100 /
2235 		max_bandwidth);
2236 
2237 	bw_used += bw_reserved;
2238 	if (bw_used > max_bandwidth) {
2239 		xhci_warn(xhci, "Not enough bandwidth. Proposed: %u, Max: %u\n",
2240 				bw_used, max_bandwidth);
2241 		return -ENOMEM;
2242 	}
2243 
2244 	bw_table->bw_used = bw_used;
2245 	return 0;
2246 }
2247 
2248 static bool xhci_is_async_ep(unsigned int ep_type)
2249 {
2250 	return (ep_type != ISOC_OUT_EP && ep_type != INT_OUT_EP &&
2251 					ep_type != ISOC_IN_EP &&
2252 					ep_type != INT_IN_EP);
2253 }
2254 
2255 static bool xhci_is_sync_in_ep(unsigned int ep_type)
2256 {
2257 	return (ep_type == ISOC_IN_EP || ep_type != INT_IN_EP);
2258 }
2259 
2260 static unsigned int xhci_get_ss_bw_consumed(struct xhci_bw_info *ep_bw)
2261 {
2262 	unsigned int mps = DIV_ROUND_UP(ep_bw->max_packet_size, SS_BLOCK);
2263 
2264 	if (ep_bw->ep_interval == 0)
2265 		return SS_OVERHEAD_BURST +
2266 			(ep_bw->mult * ep_bw->num_packets *
2267 					(SS_OVERHEAD + mps));
2268 	return DIV_ROUND_UP(ep_bw->mult * ep_bw->num_packets *
2269 				(SS_OVERHEAD + mps + SS_OVERHEAD_BURST),
2270 				1 << ep_bw->ep_interval);
2271 
2272 }
2273 
2274 void xhci_drop_ep_from_interval_table(struct xhci_hcd *xhci,
2275 		struct xhci_bw_info *ep_bw,
2276 		struct xhci_interval_bw_table *bw_table,
2277 		struct usb_device *udev,
2278 		struct xhci_virt_ep *virt_ep,
2279 		struct xhci_tt_bw_info *tt_info)
2280 {
2281 	struct xhci_interval_bw	*interval_bw;
2282 	int normalized_interval;
2283 
2284 	if (xhci_is_async_ep(ep_bw->type))
2285 		return;
2286 
2287 	if (udev->speed == USB_SPEED_SUPER) {
2288 		if (xhci_is_sync_in_ep(ep_bw->type))
2289 			xhci->devs[udev->slot_id]->bw_table->ss_bw_in -=
2290 				xhci_get_ss_bw_consumed(ep_bw);
2291 		else
2292 			xhci->devs[udev->slot_id]->bw_table->ss_bw_out -=
2293 				xhci_get_ss_bw_consumed(ep_bw);
2294 		return;
2295 	}
2296 
2297 	/* SuperSpeed endpoints never get added to intervals in the table, so
2298 	 * this check is only valid for HS/FS/LS devices.
2299 	 */
2300 	if (list_empty(&virt_ep->bw_endpoint_list))
2301 		return;
2302 	/* For LS/FS devices, we need to translate the interval expressed in
2303 	 * microframes to frames.
2304 	 */
2305 	if (udev->speed == USB_SPEED_HIGH)
2306 		normalized_interval = ep_bw->ep_interval;
2307 	else
2308 		normalized_interval = ep_bw->ep_interval - 3;
2309 
2310 	if (normalized_interval == 0)
2311 		bw_table->interval0_esit_payload -= ep_bw->max_esit_payload;
2312 	interval_bw = &bw_table->interval_bw[normalized_interval];
2313 	interval_bw->num_packets -= ep_bw->num_packets;
2314 	switch (udev->speed) {
2315 	case USB_SPEED_LOW:
2316 		interval_bw->overhead[LS_OVERHEAD_TYPE] -= 1;
2317 		break;
2318 	case USB_SPEED_FULL:
2319 		interval_bw->overhead[FS_OVERHEAD_TYPE] -= 1;
2320 		break;
2321 	case USB_SPEED_HIGH:
2322 		interval_bw->overhead[HS_OVERHEAD_TYPE] -= 1;
2323 		break;
2324 	case USB_SPEED_SUPER:
2325 	case USB_SPEED_UNKNOWN:
2326 	case USB_SPEED_WIRELESS:
2327 		/* Should never happen because only LS/FS/HS endpoints will get
2328 		 * added to the endpoint list.
2329 		 */
2330 		return;
2331 	}
2332 	if (tt_info)
2333 		tt_info->active_eps -= 1;
2334 	list_del_init(&virt_ep->bw_endpoint_list);
2335 }
2336 
2337 static void xhci_add_ep_to_interval_table(struct xhci_hcd *xhci,
2338 		struct xhci_bw_info *ep_bw,
2339 		struct xhci_interval_bw_table *bw_table,
2340 		struct usb_device *udev,
2341 		struct xhci_virt_ep *virt_ep,
2342 		struct xhci_tt_bw_info *tt_info)
2343 {
2344 	struct xhci_interval_bw	*interval_bw;
2345 	struct xhci_virt_ep *smaller_ep;
2346 	int normalized_interval;
2347 
2348 	if (xhci_is_async_ep(ep_bw->type))
2349 		return;
2350 
2351 	if (udev->speed == USB_SPEED_SUPER) {
2352 		if (xhci_is_sync_in_ep(ep_bw->type))
2353 			xhci->devs[udev->slot_id]->bw_table->ss_bw_in +=
2354 				xhci_get_ss_bw_consumed(ep_bw);
2355 		else
2356 			xhci->devs[udev->slot_id]->bw_table->ss_bw_out +=
2357 				xhci_get_ss_bw_consumed(ep_bw);
2358 		return;
2359 	}
2360 
2361 	/* For LS/FS devices, we need to translate the interval expressed in
2362 	 * microframes to frames.
2363 	 */
2364 	if (udev->speed == USB_SPEED_HIGH)
2365 		normalized_interval = ep_bw->ep_interval;
2366 	else
2367 		normalized_interval = ep_bw->ep_interval - 3;
2368 
2369 	if (normalized_interval == 0)
2370 		bw_table->interval0_esit_payload += ep_bw->max_esit_payload;
2371 	interval_bw = &bw_table->interval_bw[normalized_interval];
2372 	interval_bw->num_packets += ep_bw->num_packets;
2373 	switch (udev->speed) {
2374 	case USB_SPEED_LOW:
2375 		interval_bw->overhead[LS_OVERHEAD_TYPE] += 1;
2376 		break;
2377 	case USB_SPEED_FULL:
2378 		interval_bw->overhead[FS_OVERHEAD_TYPE] += 1;
2379 		break;
2380 	case USB_SPEED_HIGH:
2381 		interval_bw->overhead[HS_OVERHEAD_TYPE] += 1;
2382 		break;
2383 	case USB_SPEED_SUPER:
2384 	case USB_SPEED_UNKNOWN:
2385 	case USB_SPEED_WIRELESS:
2386 		/* Should never happen because only LS/FS/HS endpoints will get
2387 		 * added to the endpoint list.
2388 		 */
2389 		return;
2390 	}
2391 
2392 	if (tt_info)
2393 		tt_info->active_eps += 1;
2394 	/* Insert the endpoint into the list, largest max packet size first. */
2395 	list_for_each_entry(smaller_ep, &interval_bw->endpoints,
2396 			bw_endpoint_list) {
2397 		if (ep_bw->max_packet_size >=
2398 				smaller_ep->bw_info.max_packet_size) {
2399 			/* Add the new ep before the smaller endpoint */
2400 			list_add_tail(&virt_ep->bw_endpoint_list,
2401 					&smaller_ep->bw_endpoint_list);
2402 			return;
2403 		}
2404 	}
2405 	/* Add the new endpoint at the end of the list. */
2406 	list_add_tail(&virt_ep->bw_endpoint_list,
2407 			&interval_bw->endpoints);
2408 }
2409 
2410 void xhci_update_tt_active_eps(struct xhci_hcd *xhci,
2411 		struct xhci_virt_device *virt_dev,
2412 		int old_active_eps)
2413 {
2414 	struct xhci_root_port_bw_info *rh_bw_info;
2415 	if (!virt_dev->tt_info)
2416 		return;
2417 
2418 	rh_bw_info = &xhci->rh_bw[virt_dev->real_port - 1];
2419 	if (old_active_eps == 0 &&
2420 				virt_dev->tt_info->active_eps != 0) {
2421 		rh_bw_info->num_active_tts += 1;
2422 		rh_bw_info->bw_table.bw_used += TT_HS_OVERHEAD;
2423 	} else if (old_active_eps != 0 &&
2424 				virt_dev->tt_info->active_eps == 0) {
2425 		rh_bw_info->num_active_tts -= 1;
2426 		rh_bw_info->bw_table.bw_used -= TT_HS_OVERHEAD;
2427 	}
2428 }
2429 
2430 static int xhci_reserve_bandwidth(struct xhci_hcd *xhci,
2431 		struct xhci_virt_device *virt_dev,
2432 		struct xhci_container_ctx *in_ctx)
2433 {
2434 	struct xhci_bw_info ep_bw_info[31];
2435 	int i;
2436 	struct xhci_input_control_ctx *ctrl_ctx;
2437 	int old_active_eps = 0;
2438 
2439 	if (virt_dev->tt_info)
2440 		old_active_eps = virt_dev->tt_info->active_eps;
2441 
2442 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
2443 
2444 	for (i = 0; i < 31; i++) {
2445 		if (!EP_IS_ADDED(ctrl_ctx, i) && !EP_IS_DROPPED(ctrl_ctx, i))
2446 			continue;
2447 
2448 		/* Make a copy of the BW info in case we need to revert this */
2449 		memcpy(&ep_bw_info[i], &virt_dev->eps[i].bw_info,
2450 				sizeof(ep_bw_info[i]));
2451 		/* Drop the endpoint from the interval table if the endpoint is
2452 		 * being dropped or changed.
2453 		 */
2454 		if (EP_IS_DROPPED(ctrl_ctx, i))
2455 			xhci_drop_ep_from_interval_table(xhci,
2456 					&virt_dev->eps[i].bw_info,
2457 					virt_dev->bw_table,
2458 					virt_dev->udev,
2459 					&virt_dev->eps[i],
2460 					virt_dev->tt_info);
2461 	}
2462 	/* Overwrite the information stored in the endpoints' bw_info */
2463 	xhci_update_bw_info(xhci, virt_dev->in_ctx, ctrl_ctx, virt_dev);
2464 	for (i = 0; i < 31; i++) {
2465 		/* Add any changed or added endpoints to the interval table */
2466 		if (EP_IS_ADDED(ctrl_ctx, i))
2467 			xhci_add_ep_to_interval_table(xhci,
2468 					&virt_dev->eps[i].bw_info,
2469 					virt_dev->bw_table,
2470 					virt_dev->udev,
2471 					&virt_dev->eps[i],
2472 					virt_dev->tt_info);
2473 	}
2474 
2475 	if (!xhci_check_bw_table(xhci, virt_dev, old_active_eps)) {
2476 		/* Ok, this fits in the bandwidth we have.
2477 		 * Update the number of active TTs.
2478 		 */
2479 		xhci_update_tt_active_eps(xhci, virt_dev, old_active_eps);
2480 		return 0;
2481 	}
2482 
2483 	/* We don't have enough bandwidth for this, revert the stored info. */
2484 	for (i = 0; i < 31; i++) {
2485 		if (!EP_IS_ADDED(ctrl_ctx, i) && !EP_IS_DROPPED(ctrl_ctx, i))
2486 			continue;
2487 
2488 		/* Drop the new copies of any added or changed endpoints from
2489 		 * the interval table.
2490 		 */
2491 		if (EP_IS_ADDED(ctrl_ctx, i)) {
2492 			xhci_drop_ep_from_interval_table(xhci,
2493 					&virt_dev->eps[i].bw_info,
2494 					virt_dev->bw_table,
2495 					virt_dev->udev,
2496 					&virt_dev->eps[i],
2497 					virt_dev->tt_info);
2498 		}
2499 		/* Revert the endpoint back to its old information */
2500 		memcpy(&virt_dev->eps[i].bw_info, &ep_bw_info[i],
2501 				sizeof(ep_bw_info[i]));
2502 		/* Add any changed or dropped endpoints back into the table */
2503 		if (EP_IS_DROPPED(ctrl_ctx, i))
2504 			xhci_add_ep_to_interval_table(xhci,
2505 					&virt_dev->eps[i].bw_info,
2506 					virt_dev->bw_table,
2507 					virt_dev->udev,
2508 					&virt_dev->eps[i],
2509 					virt_dev->tt_info);
2510 	}
2511 	return -ENOMEM;
2512 }
2513 
2514 
2515 /* Issue a configure endpoint command or evaluate context command
2516  * and wait for it to finish.
2517  */
2518 static int xhci_configure_endpoint(struct xhci_hcd *xhci,
2519 		struct usb_device *udev,
2520 		struct xhci_command *command,
2521 		bool ctx_change, bool must_succeed)
2522 {
2523 	int ret;
2524 	int timeleft;
2525 	unsigned long flags;
2526 	struct xhci_container_ctx *in_ctx;
2527 	struct completion *cmd_completion;
2528 	u32 *cmd_status;
2529 	struct xhci_virt_device *virt_dev;
2530 	union xhci_trb *cmd_trb;
2531 
2532 	spin_lock_irqsave(&xhci->lock, flags);
2533 	virt_dev = xhci->devs[udev->slot_id];
2534 
2535 	if (command)
2536 		in_ctx = command->in_ctx;
2537 	else
2538 		in_ctx = virt_dev->in_ctx;
2539 
2540 	if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK) &&
2541 			xhci_reserve_host_resources(xhci, in_ctx)) {
2542 		spin_unlock_irqrestore(&xhci->lock, flags);
2543 		xhci_warn(xhci, "Not enough host resources, "
2544 				"active endpoint contexts = %u\n",
2545 				xhci->num_active_eps);
2546 		return -ENOMEM;
2547 	}
2548 	if ((xhci->quirks & XHCI_SW_BW_CHECKING) &&
2549 			xhci_reserve_bandwidth(xhci, virt_dev, in_ctx)) {
2550 		if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK))
2551 			xhci_free_host_resources(xhci, in_ctx);
2552 		spin_unlock_irqrestore(&xhci->lock, flags);
2553 		xhci_warn(xhci, "Not enough bandwidth\n");
2554 		return -ENOMEM;
2555 	}
2556 
2557 	if (command) {
2558 		cmd_completion = command->completion;
2559 		cmd_status = &command->status;
2560 		command->command_trb = xhci->cmd_ring->enqueue;
2561 
2562 		/* Enqueue pointer can be left pointing to the link TRB,
2563 		 * we must handle that
2564 		 */
2565 		if (TRB_TYPE_LINK_LE32(command->command_trb->link.control))
2566 			command->command_trb =
2567 				xhci->cmd_ring->enq_seg->next->trbs;
2568 
2569 		list_add_tail(&command->cmd_list, &virt_dev->cmd_list);
2570 	} else {
2571 		cmd_completion = &virt_dev->cmd_completion;
2572 		cmd_status = &virt_dev->cmd_status;
2573 	}
2574 	init_completion(cmd_completion);
2575 
2576 	cmd_trb = xhci->cmd_ring->dequeue;
2577 	if (!ctx_change)
2578 		ret = xhci_queue_configure_endpoint(xhci, in_ctx->dma,
2579 				udev->slot_id, must_succeed);
2580 	else
2581 		ret = xhci_queue_evaluate_context(xhci, in_ctx->dma,
2582 				udev->slot_id, must_succeed);
2583 	if (ret < 0) {
2584 		if (command)
2585 			list_del(&command->cmd_list);
2586 		if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK))
2587 			xhci_free_host_resources(xhci, in_ctx);
2588 		spin_unlock_irqrestore(&xhci->lock, flags);
2589 		xhci_dbg(xhci, "FIXME allocate a new ring segment\n");
2590 		return -ENOMEM;
2591 	}
2592 	xhci_ring_cmd_db(xhci);
2593 	spin_unlock_irqrestore(&xhci->lock, flags);
2594 
2595 	/* Wait for the configure endpoint command to complete */
2596 	timeleft = wait_for_completion_interruptible_timeout(
2597 			cmd_completion,
2598 			XHCI_CMD_DEFAULT_TIMEOUT);
2599 	if (timeleft <= 0) {
2600 		xhci_warn(xhci, "%s while waiting for %s command\n",
2601 				timeleft == 0 ? "Timeout" : "Signal",
2602 				ctx_change == 0 ?
2603 					"configure endpoint" :
2604 					"evaluate context");
2605 		/* cancel the configure endpoint command */
2606 		ret = xhci_cancel_cmd(xhci, command, cmd_trb);
2607 		if (ret < 0)
2608 			return ret;
2609 		return -ETIME;
2610 	}
2611 
2612 	if (!ctx_change)
2613 		ret = xhci_configure_endpoint_result(xhci, udev, cmd_status);
2614 	else
2615 		ret = xhci_evaluate_context_result(xhci, udev, cmd_status);
2616 
2617 	if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
2618 		spin_lock_irqsave(&xhci->lock, flags);
2619 		/* If the command failed, remove the reserved resources.
2620 		 * Otherwise, clean up the estimate to include dropped eps.
2621 		 */
2622 		if (ret)
2623 			xhci_free_host_resources(xhci, in_ctx);
2624 		else
2625 			xhci_finish_resource_reservation(xhci, in_ctx);
2626 		spin_unlock_irqrestore(&xhci->lock, flags);
2627 	}
2628 	return ret;
2629 }
2630 
2631 /* Called after one or more calls to xhci_add_endpoint() or
2632  * xhci_drop_endpoint().  If this call fails, the USB core is expected
2633  * to call xhci_reset_bandwidth().
2634  *
2635  * Since we are in the middle of changing either configuration or
2636  * installing a new alt setting, the USB core won't allow URBs to be
2637  * enqueued for any endpoint on the old config or interface.  Nothing
2638  * else should be touching the xhci->devs[slot_id] structure, so we
2639  * don't need to take the xhci->lock for manipulating that.
2640  */
2641 int xhci_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
2642 {
2643 	int i;
2644 	int ret = 0;
2645 	struct xhci_hcd *xhci;
2646 	struct xhci_virt_device	*virt_dev;
2647 	struct xhci_input_control_ctx *ctrl_ctx;
2648 	struct xhci_slot_ctx *slot_ctx;
2649 
2650 	ret = xhci_check_args(hcd, udev, NULL, 0, true, __func__);
2651 	if (ret <= 0)
2652 		return ret;
2653 	xhci = hcd_to_xhci(hcd);
2654 	if (xhci->xhc_state & XHCI_STATE_DYING)
2655 		return -ENODEV;
2656 
2657 	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
2658 	virt_dev = xhci->devs[udev->slot_id];
2659 
2660 	/* See section 4.6.6 - A0 = 1; A1 = D0 = D1 = 0 */
2661 	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
2662 	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
2663 	ctrl_ctx->add_flags &= cpu_to_le32(~EP0_FLAG);
2664 	ctrl_ctx->drop_flags &= cpu_to_le32(~(SLOT_FLAG | EP0_FLAG));
2665 
2666 	/* Don't issue the command if there's no endpoints to update. */
2667 	if (ctrl_ctx->add_flags == cpu_to_le32(SLOT_FLAG) &&
2668 			ctrl_ctx->drop_flags == 0)
2669 		return 0;
2670 
2671 	xhci_dbg(xhci, "New Input Control Context:\n");
2672 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
2673 	xhci_dbg_ctx(xhci, virt_dev->in_ctx,
2674 		     LAST_CTX_TO_EP_NUM(le32_to_cpu(slot_ctx->dev_info)));
2675 
2676 	ret = xhci_configure_endpoint(xhci, udev, NULL,
2677 			false, false);
2678 	if (ret) {
2679 		/* Callee should call reset_bandwidth() */
2680 		return ret;
2681 	}
2682 
2683 	xhci_dbg(xhci, "Output context after successful config ep cmd:\n");
2684 	xhci_dbg_ctx(xhci, virt_dev->out_ctx,
2685 		     LAST_CTX_TO_EP_NUM(le32_to_cpu(slot_ctx->dev_info)));
2686 
2687 	/* Free any rings that were dropped, but not changed. */
2688 	for (i = 1; i < 31; ++i) {
2689 		if ((le32_to_cpu(ctrl_ctx->drop_flags) & (1 << (i + 1))) &&
2690 		    !(le32_to_cpu(ctrl_ctx->add_flags) & (1 << (i + 1))))
2691 			xhci_free_or_cache_endpoint_ring(xhci, virt_dev, i);
2692 	}
2693 	xhci_zero_in_ctx(xhci, virt_dev);
2694 	/*
2695 	 * Install any rings for completely new endpoints or changed endpoints,
2696 	 * and free or cache any old rings from changed endpoints.
2697 	 */
2698 	for (i = 1; i < 31; ++i) {
2699 		if (!virt_dev->eps[i].new_ring)
2700 			continue;
2701 		/* Only cache or free the old ring if it exists.
2702 		 * It may not if this is the first add of an endpoint.
2703 		 */
2704 		if (virt_dev->eps[i].ring) {
2705 			xhci_free_or_cache_endpoint_ring(xhci, virt_dev, i);
2706 		}
2707 		virt_dev->eps[i].ring = virt_dev->eps[i].new_ring;
2708 		virt_dev->eps[i].new_ring = NULL;
2709 	}
2710 
2711 	return ret;
2712 }
2713 
2714 void xhci_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
2715 {
2716 	struct xhci_hcd *xhci;
2717 	struct xhci_virt_device	*virt_dev;
2718 	int i, ret;
2719 
2720 	ret = xhci_check_args(hcd, udev, NULL, 0, true, __func__);
2721 	if (ret <= 0)
2722 		return;
2723 	xhci = hcd_to_xhci(hcd);
2724 
2725 	xhci_dbg(xhci, "%s called for udev %p\n", __func__, udev);
2726 	virt_dev = xhci->devs[udev->slot_id];
2727 	/* Free any rings allocated for added endpoints */
2728 	for (i = 0; i < 31; ++i) {
2729 		if (virt_dev->eps[i].new_ring) {
2730 			xhci_ring_free(xhci, virt_dev->eps[i].new_ring);
2731 			virt_dev->eps[i].new_ring = NULL;
2732 		}
2733 	}
2734 	xhci_zero_in_ctx(xhci, virt_dev);
2735 }
2736 
2737 static void xhci_setup_input_ctx_for_config_ep(struct xhci_hcd *xhci,
2738 		struct xhci_container_ctx *in_ctx,
2739 		struct xhci_container_ctx *out_ctx,
2740 		u32 add_flags, u32 drop_flags)
2741 {
2742 	struct xhci_input_control_ctx *ctrl_ctx;
2743 	ctrl_ctx = xhci_get_input_control_ctx(xhci, in_ctx);
2744 	ctrl_ctx->add_flags = cpu_to_le32(add_flags);
2745 	ctrl_ctx->drop_flags = cpu_to_le32(drop_flags);
2746 	xhci_slot_copy(xhci, in_ctx, out_ctx);
2747 	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
2748 
2749 	xhci_dbg(xhci, "Input Context:\n");
2750 	xhci_dbg_ctx(xhci, in_ctx, xhci_last_valid_endpoint(add_flags));
2751 }
2752 
2753 static void xhci_setup_input_ctx_for_quirk(struct xhci_hcd *xhci,
2754 		unsigned int slot_id, unsigned int ep_index,
2755 		struct xhci_dequeue_state *deq_state)
2756 {
2757 	struct xhci_container_ctx *in_ctx;
2758 	struct xhci_ep_ctx *ep_ctx;
2759 	u32 added_ctxs;
2760 	dma_addr_t addr;
2761 
2762 	xhci_endpoint_copy(xhci, xhci->devs[slot_id]->in_ctx,
2763 			xhci->devs[slot_id]->out_ctx, ep_index);
2764 	in_ctx = xhci->devs[slot_id]->in_ctx;
2765 	ep_ctx = xhci_get_ep_ctx(xhci, in_ctx, ep_index);
2766 	addr = xhci_trb_virt_to_dma(deq_state->new_deq_seg,
2767 			deq_state->new_deq_ptr);
2768 	if (addr == 0) {
2769 		xhci_warn(xhci, "WARN Cannot submit config ep after "
2770 				"reset ep command\n");
2771 		xhci_warn(xhci, "WARN deq seg = %p, deq ptr = %p\n",
2772 				deq_state->new_deq_seg,
2773 				deq_state->new_deq_ptr);
2774 		return;
2775 	}
2776 	ep_ctx->deq = cpu_to_le64(addr | deq_state->new_cycle_state);
2777 
2778 	added_ctxs = xhci_get_endpoint_flag_from_index(ep_index);
2779 	xhci_setup_input_ctx_for_config_ep(xhci, xhci->devs[slot_id]->in_ctx,
2780 			xhci->devs[slot_id]->out_ctx, added_ctxs, added_ctxs);
2781 }
2782 
2783 void xhci_cleanup_stalled_ring(struct xhci_hcd *xhci,
2784 		struct usb_device *udev, unsigned int ep_index)
2785 {
2786 	struct xhci_dequeue_state deq_state;
2787 	struct xhci_virt_ep *ep;
2788 
2789 	xhci_dbg(xhci, "Cleaning up stalled endpoint ring\n");
2790 	ep = &xhci->devs[udev->slot_id]->eps[ep_index];
2791 	/* We need to move the HW's dequeue pointer past this TD,
2792 	 * or it will attempt to resend it on the next doorbell ring.
2793 	 */
2794 	xhci_find_new_dequeue_state(xhci, udev->slot_id,
2795 			ep_index, ep->stopped_stream, ep->stopped_td,
2796 			&deq_state);
2797 
2798 	/* HW with the reset endpoint quirk will use the saved dequeue state to
2799 	 * issue a configure endpoint command later.
2800 	 */
2801 	if (!(xhci->quirks & XHCI_RESET_EP_QUIRK)) {
2802 		xhci_dbg(xhci, "Queueing new dequeue state\n");
2803 		xhci_queue_new_dequeue_state(xhci, udev->slot_id,
2804 				ep_index, ep->stopped_stream, &deq_state);
2805 	} else {
2806 		/* Better hope no one uses the input context between now and the
2807 		 * reset endpoint completion!
2808 		 * XXX: No idea how this hardware will react when stream rings
2809 		 * are enabled.
2810 		 */
2811 		xhci_dbg(xhci, "Setting up input context for "
2812 				"configure endpoint command\n");
2813 		xhci_setup_input_ctx_for_quirk(xhci, udev->slot_id,
2814 				ep_index, &deq_state);
2815 	}
2816 }
2817 
2818 /* Deal with stalled endpoints.  The core should have sent the control message
2819  * to clear the halt condition.  However, we need to make the xHCI hardware
2820  * reset its sequence number, since a device will expect a sequence number of
2821  * zero after the halt condition is cleared.
2822  * Context: in_interrupt
2823  */
2824 void xhci_endpoint_reset(struct usb_hcd *hcd,
2825 		struct usb_host_endpoint *ep)
2826 {
2827 	struct xhci_hcd *xhci;
2828 	struct usb_device *udev;
2829 	unsigned int ep_index;
2830 	unsigned long flags;
2831 	int ret;
2832 	struct xhci_virt_ep *virt_ep;
2833 
2834 	xhci = hcd_to_xhci(hcd);
2835 	udev = (struct usb_device *) ep->hcpriv;
2836 	/* Called with a root hub endpoint (or an endpoint that wasn't added
2837 	 * with xhci_add_endpoint()
2838 	 */
2839 	if (!ep->hcpriv)
2840 		return;
2841 	ep_index = xhci_get_endpoint_index(&ep->desc);
2842 	virt_ep = &xhci->devs[udev->slot_id]->eps[ep_index];
2843 	if (!virt_ep->stopped_td) {
2844 		xhci_dbg(xhci, "Endpoint 0x%x not halted, refusing to reset.\n",
2845 				ep->desc.bEndpointAddress);
2846 		return;
2847 	}
2848 	if (usb_endpoint_xfer_control(&ep->desc)) {
2849 		xhci_dbg(xhci, "Control endpoint stall already handled.\n");
2850 		return;
2851 	}
2852 
2853 	xhci_dbg(xhci, "Queueing reset endpoint command\n");
2854 	spin_lock_irqsave(&xhci->lock, flags);
2855 	ret = xhci_queue_reset_ep(xhci, udev->slot_id, ep_index);
2856 	/*
2857 	 * Can't change the ring dequeue pointer until it's transitioned to the
2858 	 * stopped state, which is only upon a successful reset endpoint
2859 	 * command.  Better hope that last command worked!
2860 	 */
2861 	if (!ret) {
2862 		xhci_cleanup_stalled_ring(xhci, udev, ep_index);
2863 		kfree(virt_ep->stopped_td);
2864 		xhci_ring_cmd_db(xhci);
2865 	}
2866 	virt_ep->stopped_td = NULL;
2867 	virt_ep->stopped_trb = NULL;
2868 	virt_ep->stopped_stream = 0;
2869 	spin_unlock_irqrestore(&xhci->lock, flags);
2870 
2871 	if (ret)
2872 		xhci_warn(xhci, "FIXME allocate a new ring segment\n");
2873 }
2874 
2875 static int xhci_check_streams_endpoint(struct xhci_hcd *xhci,
2876 		struct usb_device *udev, struct usb_host_endpoint *ep,
2877 		unsigned int slot_id)
2878 {
2879 	int ret;
2880 	unsigned int ep_index;
2881 	unsigned int ep_state;
2882 
2883 	if (!ep)
2884 		return -EINVAL;
2885 	ret = xhci_check_args(xhci_to_hcd(xhci), udev, ep, 1, true, __func__);
2886 	if (ret <= 0)
2887 		return -EINVAL;
2888 	if (ep->ss_ep_comp.bmAttributes == 0) {
2889 		xhci_warn(xhci, "WARN: SuperSpeed Endpoint Companion"
2890 				" descriptor for ep 0x%x does not support streams\n",
2891 				ep->desc.bEndpointAddress);
2892 		return -EINVAL;
2893 	}
2894 
2895 	ep_index = xhci_get_endpoint_index(&ep->desc);
2896 	ep_state = xhci->devs[slot_id]->eps[ep_index].ep_state;
2897 	if (ep_state & EP_HAS_STREAMS ||
2898 			ep_state & EP_GETTING_STREAMS) {
2899 		xhci_warn(xhci, "WARN: SuperSpeed bulk endpoint 0x%x "
2900 				"already has streams set up.\n",
2901 				ep->desc.bEndpointAddress);
2902 		xhci_warn(xhci, "Send email to xHCI maintainer and ask for "
2903 				"dynamic stream context array reallocation.\n");
2904 		return -EINVAL;
2905 	}
2906 	if (!list_empty(&xhci->devs[slot_id]->eps[ep_index].ring->td_list)) {
2907 		xhci_warn(xhci, "Cannot setup streams for SuperSpeed bulk "
2908 				"endpoint 0x%x; URBs are pending.\n",
2909 				ep->desc.bEndpointAddress);
2910 		return -EINVAL;
2911 	}
2912 	return 0;
2913 }
2914 
2915 static void xhci_calculate_streams_entries(struct xhci_hcd *xhci,
2916 		unsigned int *num_streams, unsigned int *num_stream_ctxs)
2917 {
2918 	unsigned int max_streams;
2919 
2920 	/* The stream context array size must be a power of two */
2921 	*num_stream_ctxs = roundup_pow_of_two(*num_streams);
2922 	/*
2923 	 * Find out how many primary stream array entries the host controller
2924 	 * supports.  Later we may use secondary stream arrays (similar to 2nd
2925 	 * level page entries), but that's an optional feature for xHCI host
2926 	 * controllers. xHCs must support at least 4 stream IDs.
2927 	 */
2928 	max_streams = HCC_MAX_PSA(xhci->hcc_params);
2929 	if (*num_stream_ctxs > max_streams) {
2930 		xhci_dbg(xhci, "xHCI HW only supports %u stream ctx entries.\n",
2931 				max_streams);
2932 		*num_stream_ctxs = max_streams;
2933 		*num_streams = max_streams;
2934 	}
2935 }
2936 
2937 /* Returns an error code if one of the endpoint already has streams.
2938  * This does not change any data structures, it only checks and gathers
2939  * information.
2940  */
2941 static int xhci_calculate_streams_and_bitmask(struct xhci_hcd *xhci,
2942 		struct usb_device *udev,
2943 		struct usb_host_endpoint **eps, unsigned int num_eps,
2944 		unsigned int *num_streams, u32 *changed_ep_bitmask)
2945 {
2946 	unsigned int max_streams;
2947 	unsigned int endpoint_flag;
2948 	int i;
2949 	int ret;
2950 
2951 	for (i = 0; i < num_eps; i++) {
2952 		ret = xhci_check_streams_endpoint(xhci, udev,
2953 				eps[i], udev->slot_id);
2954 		if (ret < 0)
2955 			return ret;
2956 
2957 		max_streams = usb_ss_max_streams(&eps[i]->ss_ep_comp);
2958 		if (max_streams < (*num_streams - 1)) {
2959 			xhci_dbg(xhci, "Ep 0x%x only supports %u stream IDs.\n",
2960 					eps[i]->desc.bEndpointAddress,
2961 					max_streams);
2962 			*num_streams = max_streams+1;
2963 		}
2964 
2965 		endpoint_flag = xhci_get_endpoint_flag(&eps[i]->desc);
2966 		if (*changed_ep_bitmask & endpoint_flag)
2967 			return -EINVAL;
2968 		*changed_ep_bitmask |= endpoint_flag;
2969 	}
2970 	return 0;
2971 }
2972 
2973 static u32 xhci_calculate_no_streams_bitmask(struct xhci_hcd *xhci,
2974 		struct usb_device *udev,
2975 		struct usb_host_endpoint **eps, unsigned int num_eps)
2976 {
2977 	u32 changed_ep_bitmask = 0;
2978 	unsigned int slot_id;
2979 	unsigned int ep_index;
2980 	unsigned int ep_state;
2981 	int i;
2982 
2983 	slot_id = udev->slot_id;
2984 	if (!xhci->devs[slot_id])
2985 		return 0;
2986 
2987 	for (i = 0; i < num_eps; i++) {
2988 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
2989 		ep_state = xhci->devs[slot_id]->eps[ep_index].ep_state;
2990 		/* Are streams already being freed for the endpoint? */
2991 		if (ep_state & EP_GETTING_NO_STREAMS) {
2992 			xhci_warn(xhci, "WARN Can't disable streams for "
2993 					"endpoint 0x%x\n, "
2994 					"streams are being disabled already.",
2995 					eps[i]->desc.bEndpointAddress);
2996 			return 0;
2997 		}
2998 		/* Are there actually any streams to free? */
2999 		if (!(ep_state & EP_HAS_STREAMS) &&
3000 				!(ep_state & EP_GETTING_STREAMS)) {
3001 			xhci_warn(xhci, "WARN Can't disable streams for "
3002 					"endpoint 0x%x\n, "
3003 					"streams are already disabled!",
3004 					eps[i]->desc.bEndpointAddress);
3005 			xhci_warn(xhci, "WARN xhci_free_streams() called "
3006 					"with non-streams endpoint\n");
3007 			return 0;
3008 		}
3009 		changed_ep_bitmask |= xhci_get_endpoint_flag(&eps[i]->desc);
3010 	}
3011 	return changed_ep_bitmask;
3012 }
3013 
3014 /*
3015  * The USB device drivers use this function (though the HCD interface in USB
3016  * core) to prepare a set of bulk endpoints to use streams.  Streams are used to
3017  * coordinate mass storage command queueing across multiple endpoints (basically
3018  * a stream ID == a task ID).
3019  *
3020  * Setting up streams involves allocating the same size stream context array
3021  * for each endpoint and issuing a configure endpoint command for all endpoints.
3022  *
3023  * Don't allow the call to succeed if one endpoint only supports one stream
3024  * (which means it doesn't support streams at all).
3025  *
3026  * Drivers may get less stream IDs than they asked for, if the host controller
3027  * hardware or endpoints claim they can't support the number of requested
3028  * stream IDs.
3029  */
3030 int xhci_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
3031 		struct usb_host_endpoint **eps, unsigned int num_eps,
3032 		unsigned int num_streams, gfp_t mem_flags)
3033 {
3034 	int i, ret;
3035 	struct xhci_hcd *xhci;
3036 	struct xhci_virt_device *vdev;
3037 	struct xhci_command *config_cmd;
3038 	unsigned int ep_index;
3039 	unsigned int num_stream_ctxs;
3040 	unsigned long flags;
3041 	u32 changed_ep_bitmask = 0;
3042 
3043 	if (!eps)
3044 		return -EINVAL;
3045 
3046 	/* Add one to the number of streams requested to account for
3047 	 * stream 0 that is reserved for xHCI usage.
3048 	 */
3049 	num_streams += 1;
3050 	xhci = hcd_to_xhci(hcd);
3051 	xhci_dbg(xhci, "Driver wants %u stream IDs (including stream 0).\n",
3052 			num_streams);
3053 
3054 	config_cmd = xhci_alloc_command(xhci, true, true, mem_flags);
3055 	if (!config_cmd) {
3056 		xhci_dbg(xhci, "Could not allocate xHCI command structure.\n");
3057 		return -ENOMEM;
3058 	}
3059 
3060 	/* Check to make sure all endpoints are not already configured for
3061 	 * streams.  While we're at it, find the maximum number of streams that
3062 	 * all the endpoints will support and check for duplicate endpoints.
3063 	 */
3064 	spin_lock_irqsave(&xhci->lock, flags);
3065 	ret = xhci_calculate_streams_and_bitmask(xhci, udev, eps,
3066 			num_eps, &num_streams, &changed_ep_bitmask);
3067 	if (ret < 0) {
3068 		xhci_free_command(xhci, config_cmd);
3069 		spin_unlock_irqrestore(&xhci->lock, flags);
3070 		return ret;
3071 	}
3072 	if (num_streams <= 1) {
3073 		xhci_warn(xhci, "WARN: endpoints can't handle "
3074 				"more than one stream.\n");
3075 		xhci_free_command(xhci, config_cmd);
3076 		spin_unlock_irqrestore(&xhci->lock, flags);
3077 		return -EINVAL;
3078 	}
3079 	vdev = xhci->devs[udev->slot_id];
3080 	/* Mark each endpoint as being in transition, so
3081 	 * xhci_urb_enqueue() will reject all URBs.
3082 	 */
3083 	for (i = 0; i < num_eps; i++) {
3084 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3085 		vdev->eps[ep_index].ep_state |= EP_GETTING_STREAMS;
3086 	}
3087 	spin_unlock_irqrestore(&xhci->lock, flags);
3088 
3089 	/* Setup internal data structures and allocate HW data structures for
3090 	 * streams (but don't install the HW structures in the input context
3091 	 * until we're sure all memory allocation succeeded).
3092 	 */
3093 	xhci_calculate_streams_entries(xhci, &num_streams, &num_stream_ctxs);
3094 	xhci_dbg(xhci, "Need %u stream ctx entries for %u stream IDs.\n",
3095 			num_stream_ctxs, num_streams);
3096 
3097 	for (i = 0; i < num_eps; i++) {
3098 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3099 		vdev->eps[ep_index].stream_info = xhci_alloc_stream_info(xhci,
3100 				num_stream_ctxs,
3101 				num_streams, mem_flags);
3102 		if (!vdev->eps[ep_index].stream_info)
3103 			goto cleanup;
3104 		/* Set maxPstreams in endpoint context and update deq ptr to
3105 		 * point to stream context array. FIXME
3106 		 */
3107 	}
3108 
3109 	/* Set up the input context for a configure endpoint command. */
3110 	for (i = 0; i < num_eps; i++) {
3111 		struct xhci_ep_ctx *ep_ctx;
3112 
3113 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3114 		ep_ctx = xhci_get_ep_ctx(xhci, config_cmd->in_ctx, ep_index);
3115 
3116 		xhci_endpoint_copy(xhci, config_cmd->in_ctx,
3117 				vdev->out_ctx, ep_index);
3118 		xhci_setup_streams_ep_input_ctx(xhci, ep_ctx,
3119 				vdev->eps[ep_index].stream_info);
3120 	}
3121 	/* Tell the HW to drop its old copy of the endpoint context info
3122 	 * and add the updated copy from the input context.
3123 	 */
3124 	xhci_setup_input_ctx_for_config_ep(xhci, config_cmd->in_ctx,
3125 			vdev->out_ctx, changed_ep_bitmask, changed_ep_bitmask);
3126 
3127 	/* Issue and wait for the configure endpoint command */
3128 	ret = xhci_configure_endpoint(xhci, udev, config_cmd,
3129 			false, false);
3130 
3131 	/* xHC rejected the configure endpoint command for some reason, so we
3132 	 * leave the old ring intact and free our internal streams data
3133 	 * structure.
3134 	 */
3135 	if (ret < 0)
3136 		goto cleanup;
3137 
3138 	spin_lock_irqsave(&xhci->lock, flags);
3139 	for (i = 0; i < num_eps; i++) {
3140 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3141 		vdev->eps[ep_index].ep_state &= ~EP_GETTING_STREAMS;
3142 		xhci_dbg(xhci, "Slot %u ep ctx %u now has streams.\n",
3143 			 udev->slot_id, ep_index);
3144 		vdev->eps[ep_index].ep_state |= EP_HAS_STREAMS;
3145 	}
3146 	xhci_free_command(xhci, config_cmd);
3147 	spin_unlock_irqrestore(&xhci->lock, flags);
3148 
3149 	/* Subtract 1 for stream 0, which drivers can't use */
3150 	return num_streams - 1;
3151 
3152 cleanup:
3153 	/* If it didn't work, free the streams! */
3154 	for (i = 0; i < num_eps; i++) {
3155 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3156 		xhci_free_stream_info(xhci, vdev->eps[ep_index].stream_info);
3157 		vdev->eps[ep_index].stream_info = NULL;
3158 		/* FIXME Unset maxPstreams in endpoint context and
3159 		 * update deq ptr to point to normal string ring.
3160 		 */
3161 		vdev->eps[ep_index].ep_state &= ~EP_GETTING_STREAMS;
3162 		vdev->eps[ep_index].ep_state &= ~EP_HAS_STREAMS;
3163 		xhci_endpoint_zero(xhci, vdev, eps[i]);
3164 	}
3165 	xhci_free_command(xhci, config_cmd);
3166 	return -ENOMEM;
3167 }
3168 
3169 /* Transition the endpoint from using streams to being a "normal" endpoint
3170  * without streams.
3171  *
3172  * Modify the endpoint context state, submit a configure endpoint command,
3173  * and free all endpoint rings for streams if that completes successfully.
3174  */
3175 int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
3176 		struct usb_host_endpoint **eps, unsigned int num_eps,
3177 		gfp_t mem_flags)
3178 {
3179 	int i, ret;
3180 	struct xhci_hcd *xhci;
3181 	struct xhci_virt_device *vdev;
3182 	struct xhci_command *command;
3183 	unsigned int ep_index;
3184 	unsigned long flags;
3185 	u32 changed_ep_bitmask;
3186 
3187 	xhci = hcd_to_xhci(hcd);
3188 	vdev = xhci->devs[udev->slot_id];
3189 
3190 	/* Set up a configure endpoint command to remove the streams rings */
3191 	spin_lock_irqsave(&xhci->lock, flags);
3192 	changed_ep_bitmask = xhci_calculate_no_streams_bitmask(xhci,
3193 			udev, eps, num_eps);
3194 	if (changed_ep_bitmask == 0) {
3195 		spin_unlock_irqrestore(&xhci->lock, flags);
3196 		return -EINVAL;
3197 	}
3198 
3199 	/* Use the xhci_command structure from the first endpoint.  We may have
3200 	 * allocated too many, but the driver may call xhci_free_streams() for
3201 	 * each endpoint it grouped into one call to xhci_alloc_streams().
3202 	 */
3203 	ep_index = xhci_get_endpoint_index(&eps[0]->desc);
3204 	command = vdev->eps[ep_index].stream_info->free_streams_command;
3205 	for (i = 0; i < num_eps; i++) {
3206 		struct xhci_ep_ctx *ep_ctx;
3207 
3208 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3209 		ep_ctx = xhci_get_ep_ctx(xhci, command->in_ctx, ep_index);
3210 		xhci->devs[udev->slot_id]->eps[ep_index].ep_state |=
3211 			EP_GETTING_NO_STREAMS;
3212 
3213 		xhci_endpoint_copy(xhci, command->in_ctx,
3214 				vdev->out_ctx, ep_index);
3215 		xhci_setup_no_streams_ep_input_ctx(xhci, ep_ctx,
3216 				&vdev->eps[ep_index]);
3217 	}
3218 	xhci_setup_input_ctx_for_config_ep(xhci, command->in_ctx,
3219 			vdev->out_ctx, changed_ep_bitmask, changed_ep_bitmask);
3220 	spin_unlock_irqrestore(&xhci->lock, flags);
3221 
3222 	/* Issue and wait for the configure endpoint command,
3223 	 * which must succeed.
3224 	 */
3225 	ret = xhci_configure_endpoint(xhci, udev, command,
3226 			false, true);
3227 
3228 	/* xHC rejected the configure endpoint command for some reason, so we
3229 	 * leave the streams rings intact.
3230 	 */
3231 	if (ret < 0)
3232 		return ret;
3233 
3234 	spin_lock_irqsave(&xhci->lock, flags);
3235 	for (i = 0; i < num_eps; i++) {
3236 		ep_index = xhci_get_endpoint_index(&eps[i]->desc);
3237 		xhci_free_stream_info(xhci, vdev->eps[ep_index].stream_info);
3238 		vdev->eps[ep_index].stream_info = NULL;
3239 		/* FIXME Unset maxPstreams in endpoint context and
3240 		 * update deq ptr to point to normal string ring.
3241 		 */
3242 		vdev->eps[ep_index].ep_state &= ~EP_GETTING_NO_STREAMS;
3243 		vdev->eps[ep_index].ep_state &= ~EP_HAS_STREAMS;
3244 	}
3245 	spin_unlock_irqrestore(&xhci->lock, flags);
3246 
3247 	return 0;
3248 }
3249 
3250 /*
3251  * Deletes endpoint resources for endpoints that were active before a Reset
3252  * Device command, or a Disable Slot command.  The Reset Device command leaves
3253  * the control endpoint intact, whereas the Disable Slot command deletes it.
3254  *
3255  * Must be called with xhci->lock held.
3256  */
3257 void xhci_free_device_endpoint_resources(struct xhci_hcd *xhci,
3258 	struct xhci_virt_device *virt_dev, bool drop_control_ep)
3259 {
3260 	int i;
3261 	unsigned int num_dropped_eps = 0;
3262 	unsigned int drop_flags = 0;
3263 
3264 	for (i = (drop_control_ep ? 0 : 1); i < 31; i++) {
3265 		if (virt_dev->eps[i].ring) {
3266 			drop_flags |= 1 << i;
3267 			num_dropped_eps++;
3268 		}
3269 	}
3270 	xhci->num_active_eps -= num_dropped_eps;
3271 	if (num_dropped_eps)
3272 		xhci_dbg(xhci, "Dropped %u ep ctxs, flags = 0x%x, "
3273 				"%u now active.\n",
3274 				num_dropped_eps, drop_flags,
3275 				xhci->num_active_eps);
3276 }
3277 
3278 /*
3279  * This submits a Reset Device Command, which will set the device state to 0,
3280  * set the device address to 0, and disable all the endpoints except the default
3281  * control endpoint.  The USB core should come back and call
3282  * xhci_address_device(), and then re-set up the configuration.  If this is
3283  * called because of a usb_reset_and_verify_device(), then the old alternate
3284  * settings will be re-installed through the normal bandwidth allocation
3285  * functions.
3286  *
3287  * Wait for the Reset Device command to finish.  Remove all structures
3288  * associated with the endpoints that were disabled.  Clear the input device
3289  * structure?  Cache the rings?  Reset the control endpoint 0 max packet size?
3290  *
3291  * If the virt_dev to be reset does not exist or does not match the udev,
3292  * it means the device is lost, possibly due to the xHC restore error and
3293  * re-initialization during S3/S4. In this case, call xhci_alloc_dev() to
3294  * re-allocate the device.
3295  */
3296 int xhci_discover_or_reset_device(struct usb_hcd *hcd, struct usb_device *udev)
3297 {
3298 	int ret, i;
3299 	unsigned long flags;
3300 	struct xhci_hcd *xhci;
3301 	unsigned int slot_id;
3302 	struct xhci_virt_device *virt_dev;
3303 	struct xhci_command *reset_device_cmd;
3304 	int timeleft;
3305 	int last_freed_endpoint;
3306 	struct xhci_slot_ctx *slot_ctx;
3307 	int old_active_eps = 0;
3308 
3309 	ret = xhci_check_args(hcd, udev, NULL, 0, false, __func__);
3310 	if (ret <= 0)
3311 		return ret;
3312 	xhci = hcd_to_xhci(hcd);
3313 	slot_id = udev->slot_id;
3314 	virt_dev = xhci->devs[slot_id];
3315 	if (!virt_dev) {
3316 		xhci_dbg(xhci, "The device to be reset with slot ID %u does "
3317 				"not exist. Re-allocate the device\n", slot_id);
3318 		ret = xhci_alloc_dev(hcd, udev);
3319 		if (ret == 1)
3320 			return 0;
3321 		else
3322 			return -EINVAL;
3323 	}
3324 
3325 	if (virt_dev->udev != udev) {
3326 		/* If the virt_dev and the udev does not match, this virt_dev
3327 		 * may belong to another udev.
3328 		 * Re-allocate the device.
3329 		 */
3330 		xhci_dbg(xhci, "The device to be reset with slot ID %u does "
3331 				"not match the udev. Re-allocate the device\n",
3332 				slot_id);
3333 		ret = xhci_alloc_dev(hcd, udev);
3334 		if (ret == 1)
3335 			return 0;
3336 		else
3337 			return -EINVAL;
3338 	}
3339 
3340 	/* If device is not setup, there is no point in resetting it */
3341 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
3342 	if (GET_SLOT_STATE(le32_to_cpu(slot_ctx->dev_state)) ==
3343 						SLOT_STATE_DISABLED)
3344 		return 0;
3345 
3346 	xhci_dbg(xhci, "Resetting device with slot ID %u\n", slot_id);
3347 	/* Allocate the command structure that holds the struct completion.
3348 	 * Assume we're in process context, since the normal device reset
3349 	 * process has to wait for the device anyway.  Storage devices are
3350 	 * reset as part of error handling, so use GFP_NOIO instead of
3351 	 * GFP_KERNEL.
3352 	 */
3353 	reset_device_cmd = xhci_alloc_command(xhci, false, true, GFP_NOIO);
3354 	if (!reset_device_cmd) {
3355 		xhci_dbg(xhci, "Couldn't allocate command structure.\n");
3356 		return -ENOMEM;
3357 	}
3358 
3359 	/* Attempt to submit the Reset Device command to the command ring */
3360 	spin_lock_irqsave(&xhci->lock, flags);
3361 	reset_device_cmd->command_trb = xhci->cmd_ring->enqueue;
3362 
3363 	/* Enqueue pointer can be left pointing to the link TRB,
3364 	 * we must handle that
3365 	 */
3366 	if (TRB_TYPE_LINK_LE32(reset_device_cmd->command_trb->link.control))
3367 		reset_device_cmd->command_trb =
3368 			xhci->cmd_ring->enq_seg->next->trbs;
3369 
3370 	list_add_tail(&reset_device_cmd->cmd_list, &virt_dev->cmd_list);
3371 	ret = xhci_queue_reset_device(xhci, slot_id);
3372 	if (ret) {
3373 		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
3374 		list_del(&reset_device_cmd->cmd_list);
3375 		spin_unlock_irqrestore(&xhci->lock, flags);
3376 		goto command_cleanup;
3377 	}
3378 	xhci_ring_cmd_db(xhci);
3379 	spin_unlock_irqrestore(&xhci->lock, flags);
3380 
3381 	/* Wait for the Reset Device command to finish */
3382 	timeleft = wait_for_completion_interruptible_timeout(
3383 			reset_device_cmd->completion,
3384 			USB_CTRL_SET_TIMEOUT);
3385 	if (timeleft <= 0) {
3386 		xhci_warn(xhci, "%s while waiting for reset device command\n",
3387 				timeleft == 0 ? "Timeout" : "Signal");
3388 		spin_lock_irqsave(&xhci->lock, flags);
3389 		/* The timeout might have raced with the event ring handler, so
3390 		 * only delete from the list if the item isn't poisoned.
3391 		 */
3392 		if (reset_device_cmd->cmd_list.next != LIST_POISON1)
3393 			list_del(&reset_device_cmd->cmd_list);
3394 		spin_unlock_irqrestore(&xhci->lock, flags);
3395 		ret = -ETIME;
3396 		goto command_cleanup;
3397 	}
3398 
3399 	/* The Reset Device command can't fail, according to the 0.95/0.96 spec,
3400 	 * unless we tried to reset a slot ID that wasn't enabled,
3401 	 * or the device wasn't in the addressed or configured state.
3402 	 */
3403 	ret = reset_device_cmd->status;
3404 	switch (ret) {
3405 	case COMP_EBADSLT: /* 0.95 completion code for bad slot ID */
3406 	case COMP_CTX_STATE: /* 0.96 completion code for same thing */
3407 		xhci_info(xhci, "Can't reset device (slot ID %u) in %s state\n",
3408 				slot_id,
3409 				xhci_get_slot_state(xhci, virt_dev->out_ctx));
3410 		xhci_info(xhci, "Not freeing device rings.\n");
3411 		/* Don't treat this as an error.  May change my mind later. */
3412 		ret = 0;
3413 		goto command_cleanup;
3414 	case COMP_SUCCESS:
3415 		xhci_dbg(xhci, "Successful reset device command.\n");
3416 		break;
3417 	default:
3418 		if (xhci_is_vendor_info_code(xhci, ret))
3419 			break;
3420 		xhci_warn(xhci, "Unknown completion code %u for "
3421 				"reset device command.\n", ret);
3422 		ret = -EINVAL;
3423 		goto command_cleanup;
3424 	}
3425 
3426 	/* Free up host controller endpoint resources */
3427 	if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
3428 		spin_lock_irqsave(&xhci->lock, flags);
3429 		/* Don't delete the default control endpoint resources */
3430 		xhci_free_device_endpoint_resources(xhci, virt_dev, false);
3431 		spin_unlock_irqrestore(&xhci->lock, flags);
3432 	}
3433 
3434 	/* Everything but endpoint 0 is disabled, so free or cache the rings. */
3435 	last_freed_endpoint = 1;
3436 	for (i = 1; i < 31; ++i) {
3437 		struct xhci_virt_ep *ep = &virt_dev->eps[i];
3438 
3439 		if (ep->ep_state & EP_HAS_STREAMS) {
3440 			xhci_free_stream_info(xhci, ep->stream_info);
3441 			ep->stream_info = NULL;
3442 			ep->ep_state &= ~EP_HAS_STREAMS;
3443 		}
3444 
3445 		if (ep->ring) {
3446 			xhci_free_or_cache_endpoint_ring(xhci, virt_dev, i);
3447 			last_freed_endpoint = i;
3448 		}
3449 		if (!list_empty(&virt_dev->eps[i].bw_endpoint_list))
3450 			xhci_drop_ep_from_interval_table(xhci,
3451 					&virt_dev->eps[i].bw_info,
3452 					virt_dev->bw_table,
3453 					udev,
3454 					&virt_dev->eps[i],
3455 					virt_dev->tt_info);
3456 		xhci_clear_endpoint_bw_info(&virt_dev->eps[i].bw_info);
3457 	}
3458 	/* If necessary, update the number of active TTs on this root port */
3459 	xhci_update_tt_active_eps(xhci, virt_dev, old_active_eps);
3460 
3461 	xhci_dbg(xhci, "Output context after successful reset device cmd:\n");
3462 	xhci_dbg_ctx(xhci, virt_dev->out_ctx, last_freed_endpoint);
3463 	ret = 0;
3464 
3465 command_cleanup:
3466 	xhci_free_command(xhci, reset_device_cmd);
3467 	return ret;
3468 }
3469 
3470 /*
3471  * At this point, the struct usb_device is about to go away, the device has
3472  * disconnected, and all traffic has been stopped and the endpoints have been
3473  * disabled.  Free any HC data structures associated with that device.
3474  */
3475 void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
3476 {
3477 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
3478 	struct xhci_virt_device *virt_dev;
3479 	unsigned long flags;
3480 	u32 state;
3481 	int i, ret;
3482 
3483 	ret = xhci_check_args(hcd, udev, NULL, 0, true, __func__);
3484 	/* If the host is halted due to driver unload, we still need to free the
3485 	 * device.
3486 	 */
3487 	if (ret <= 0 && ret != -ENODEV)
3488 		return;
3489 
3490 	virt_dev = xhci->devs[udev->slot_id];
3491 
3492 	/* Stop any wayward timer functions (which may grab the lock) */
3493 	for (i = 0; i < 31; ++i) {
3494 		virt_dev->eps[i].ep_state &= ~EP_HALT_PENDING;
3495 		del_timer_sync(&virt_dev->eps[i].stop_cmd_timer);
3496 	}
3497 
3498 	if (udev->usb2_hw_lpm_enabled) {
3499 		xhci_set_usb2_hardware_lpm(hcd, udev, 0);
3500 		udev->usb2_hw_lpm_enabled = 0;
3501 	}
3502 
3503 	spin_lock_irqsave(&xhci->lock, flags);
3504 	/* Don't disable the slot if the host controller is dead. */
3505 	state = xhci_readl(xhci, &xhci->op_regs->status);
3506 	if (state == 0xffffffff || (xhci->xhc_state & XHCI_STATE_DYING) ||
3507 			(xhci->xhc_state & XHCI_STATE_HALTED)) {
3508 		xhci_free_virt_device(xhci, udev->slot_id);
3509 		spin_unlock_irqrestore(&xhci->lock, flags);
3510 		return;
3511 	}
3512 
3513 	if (xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id)) {
3514 		spin_unlock_irqrestore(&xhci->lock, flags);
3515 		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
3516 		return;
3517 	}
3518 	xhci_ring_cmd_db(xhci);
3519 	spin_unlock_irqrestore(&xhci->lock, flags);
3520 	/*
3521 	 * Event command completion handler will free any data structures
3522 	 * associated with the slot.  XXX Can free sleep?
3523 	 */
3524 }
3525 
3526 /*
3527  * Checks if we have enough host controller resources for the default control
3528  * endpoint.
3529  *
3530  * Must be called with xhci->lock held.
3531  */
3532 static int xhci_reserve_host_control_ep_resources(struct xhci_hcd *xhci)
3533 {
3534 	if (xhci->num_active_eps + 1 > xhci->limit_active_eps) {
3535 		xhci_dbg(xhci, "Not enough ep ctxs: "
3536 				"%u active, need to add 1, limit is %u.\n",
3537 				xhci->num_active_eps, xhci->limit_active_eps);
3538 		return -ENOMEM;
3539 	}
3540 	xhci->num_active_eps += 1;
3541 	xhci_dbg(xhci, "Adding 1 ep ctx, %u now active.\n",
3542 			xhci->num_active_eps);
3543 	return 0;
3544 }
3545 
3546 
3547 /*
3548  * Returns 0 if the xHC ran out of device slots, the Enable Slot command
3549  * timed out, or allocating memory failed.  Returns 1 on success.
3550  */
3551 int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
3552 {
3553 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
3554 	unsigned long flags;
3555 	int timeleft;
3556 	int ret;
3557 	union xhci_trb *cmd_trb;
3558 
3559 	spin_lock_irqsave(&xhci->lock, flags);
3560 	cmd_trb = xhci->cmd_ring->dequeue;
3561 	ret = xhci_queue_slot_control(xhci, TRB_ENABLE_SLOT, 0);
3562 	if (ret) {
3563 		spin_unlock_irqrestore(&xhci->lock, flags);
3564 		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
3565 		return 0;
3566 	}
3567 	xhci_ring_cmd_db(xhci);
3568 	spin_unlock_irqrestore(&xhci->lock, flags);
3569 
3570 	/* XXX: how much time for xHC slot assignment? */
3571 	timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev,
3572 			XHCI_CMD_DEFAULT_TIMEOUT);
3573 	if (timeleft <= 0) {
3574 		xhci_warn(xhci, "%s while waiting for a slot\n",
3575 				timeleft == 0 ? "Timeout" : "Signal");
3576 		/* cancel the enable slot request */
3577 		return xhci_cancel_cmd(xhci, NULL, cmd_trb);
3578 	}
3579 
3580 	if (!xhci->slot_id) {
3581 		xhci_err(xhci, "Error while assigning device slot ID\n");
3582 		return 0;
3583 	}
3584 
3585 	if ((xhci->quirks & XHCI_EP_LIMIT_QUIRK)) {
3586 		spin_lock_irqsave(&xhci->lock, flags);
3587 		ret = xhci_reserve_host_control_ep_resources(xhci);
3588 		if (ret) {
3589 			spin_unlock_irqrestore(&xhci->lock, flags);
3590 			xhci_warn(xhci, "Not enough host resources, "
3591 					"active endpoint contexts = %u\n",
3592 					xhci->num_active_eps);
3593 			goto disable_slot;
3594 		}
3595 		spin_unlock_irqrestore(&xhci->lock, flags);
3596 	}
3597 	/* Use GFP_NOIO, since this function can be called from
3598 	 * xhci_discover_or_reset_device(), which may be called as part of
3599 	 * mass storage driver error handling.
3600 	 */
3601 	if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_NOIO)) {
3602 		xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n");
3603 		goto disable_slot;
3604 	}
3605 	udev->slot_id = xhci->slot_id;
3606 	/* Is this a LS or FS device under a HS hub? */
3607 	/* Hub or peripherial? */
3608 	return 1;
3609 
3610 disable_slot:
3611 	/* Disable slot, if we can do it without mem alloc */
3612 	spin_lock_irqsave(&xhci->lock, flags);
3613 	if (!xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id))
3614 		xhci_ring_cmd_db(xhci);
3615 	spin_unlock_irqrestore(&xhci->lock, flags);
3616 	return 0;
3617 }
3618 
3619 /*
3620  * Issue an Address Device command (which will issue a SetAddress request to
3621  * the device).
3622  * We should be protected by the usb_address0_mutex in khubd's hub_port_init, so
3623  * we should only issue and wait on one address command at the same time.
3624  *
3625  * We add one to the device address issued by the hardware because the USB core
3626  * uses address 1 for the root hubs (even though they're not really devices).
3627  */
3628 int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
3629 {
3630 	unsigned long flags;
3631 	int timeleft;
3632 	struct xhci_virt_device *virt_dev;
3633 	int ret = 0;
3634 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
3635 	struct xhci_slot_ctx *slot_ctx;
3636 	struct xhci_input_control_ctx *ctrl_ctx;
3637 	u64 temp_64;
3638 	union xhci_trb *cmd_trb;
3639 
3640 	if (!udev->slot_id) {
3641 		xhci_dbg(xhci, "Bad Slot ID %d\n", udev->slot_id);
3642 		return -EINVAL;
3643 	}
3644 
3645 	virt_dev = xhci->devs[udev->slot_id];
3646 
3647 	if (WARN_ON(!virt_dev)) {
3648 		/*
3649 		 * In plug/unplug torture test with an NEC controller,
3650 		 * a zero-dereference was observed once due to virt_dev = 0.
3651 		 * Print useful debug rather than crash if it is observed again!
3652 		 */
3653 		xhci_warn(xhci, "Virt dev invalid for slot_id 0x%x!\n",
3654 			udev->slot_id);
3655 		return -EINVAL;
3656 	}
3657 
3658 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
3659 	/*
3660 	 * If this is the first Set Address since device plug-in or
3661 	 * virt_device realloaction after a resume with an xHCI power loss,
3662 	 * then set up the slot context.
3663 	 */
3664 	if (!slot_ctx->dev_info)
3665 		xhci_setup_addressable_virt_dev(xhci, udev);
3666 	/* Otherwise, update the control endpoint ring enqueue pointer. */
3667 	else
3668 		xhci_copy_ep0_dequeue_into_input_ctx(xhci, udev);
3669 	ctrl_ctx = xhci_get_input_control_ctx(xhci, virt_dev->in_ctx);
3670 	ctrl_ctx->add_flags = cpu_to_le32(SLOT_FLAG | EP0_FLAG);
3671 	ctrl_ctx->drop_flags = 0;
3672 
3673 	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
3674 	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
3675 
3676 	spin_lock_irqsave(&xhci->lock, flags);
3677 	cmd_trb = xhci->cmd_ring->dequeue;
3678 	ret = xhci_queue_address_device(xhci, virt_dev->in_ctx->dma,
3679 					udev->slot_id);
3680 	if (ret) {
3681 		spin_unlock_irqrestore(&xhci->lock, flags);
3682 		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");
3683 		return ret;
3684 	}
3685 	xhci_ring_cmd_db(xhci);
3686 	spin_unlock_irqrestore(&xhci->lock, flags);
3687 
3688 	/* ctrl tx can take up to 5 sec; XXX: need more time for xHC? */
3689 	timeleft = wait_for_completion_interruptible_timeout(&xhci->addr_dev,
3690 			XHCI_CMD_DEFAULT_TIMEOUT);
3691 	/* FIXME: From section 4.3.4: "Software shall be responsible for timing
3692 	 * the SetAddress() "recovery interval" required by USB and aborting the
3693 	 * command on a timeout.
3694 	 */
3695 	if (timeleft <= 0) {
3696 		xhci_warn(xhci, "%s while waiting for address device command\n",
3697 				timeleft == 0 ? "Timeout" : "Signal");
3698 		/* cancel the address device command */
3699 		ret = xhci_cancel_cmd(xhci, NULL, cmd_trb);
3700 		if (ret < 0)
3701 			return ret;
3702 		return -ETIME;
3703 	}
3704 
3705 	switch (virt_dev->cmd_status) {
3706 	case COMP_CTX_STATE:
3707 	case COMP_EBADSLT:
3708 		xhci_err(xhci, "Setup ERROR: address device command for slot %d.\n",
3709 				udev->slot_id);
3710 		ret = -EINVAL;
3711 		break;
3712 	case COMP_TX_ERR:
3713 		dev_warn(&udev->dev, "Device not responding to set address.\n");
3714 		ret = -EPROTO;
3715 		break;
3716 	case COMP_DEV_ERR:
3717 		dev_warn(&udev->dev, "ERROR: Incompatible device for address "
3718 				"device command.\n");
3719 		ret = -ENODEV;
3720 		break;
3721 	case COMP_SUCCESS:
3722 		xhci_dbg(xhci, "Successful Address Device command\n");
3723 		break;
3724 	default:
3725 		xhci_err(xhci, "ERROR: unexpected command completion "
3726 				"code 0x%x.\n", virt_dev->cmd_status);
3727 		xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
3728 		xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
3729 		ret = -EINVAL;
3730 		break;
3731 	}
3732 	if (ret) {
3733 		return ret;
3734 	}
3735 	temp_64 = xhci_read_64(xhci, &xhci->op_regs->dcbaa_ptr);
3736 	xhci_dbg(xhci, "Op regs DCBAA ptr = %#016llx\n", temp_64);
3737 	xhci_dbg(xhci, "Slot ID %d dcbaa entry @%p = %#016llx\n",
3738 		 udev->slot_id,
3739 		 &xhci->dcbaa->dev_context_ptrs[udev->slot_id],
3740 		 (unsigned long long)
3741 		 le64_to_cpu(xhci->dcbaa->dev_context_ptrs[udev->slot_id]));
3742 	xhci_dbg(xhci, "Output Context DMA address = %#08llx\n",
3743 			(unsigned long long)virt_dev->out_ctx->dma);
3744 	xhci_dbg(xhci, "Slot ID %d Input Context:\n", udev->slot_id);
3745 	xhci_dbg_ctx(xhci, virt_dev->in_ctx, 2);
3746 	xhci_dbg(xhci, "Slot ID %d Output Context:\n", udev->slot_id);
3747 	xhci_dbg_ctx(xhci, virt_dev->out_ctx, 2);
3748 	/*
3749 	 * USB core uses address 1 for the roothubs, so we add one to the
3750 	 * address given back to us by the HC.
3751 	 */
3752 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
3753 	/* Use kernel assigned address for devices; store xHC assigned
3754 	 * address locally. */
3755 	virt_dev->address = (le32_to_cpu(slot_ctx->dev_state) & DEV_ADDR_MASK)
3756 		+ 1;
3757 	/* Zero the input context control for later use */
3758 	ctrl_ctx->add_flags = 0;
3759 	ctrl_ctx->drop_flags = 0;
3760 
3761 	xhci_dbg(xhci, "Internal device address = %d\n", virt_dev->address);
3762 
3763 	return 0;
3764 }
3765 
3766 #ifdef CONFIG_USB_SUSPEND
3767 
3768 /* BESL to HIRD Encoding array for USB2 LPM */
3769 static int xhci_besl_encoding[16] = {125, 150, 200, 300, 400, 500, 1000, 2000,
3770 	3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000};
3771 
3772 /* Calculate HIRD/BESL for USB2 PORTPMSC*/
3773 static int xhci_calculate_hird_besl(struct xhci_hcd *xhci,
3774 					struct usb_device *udev)
3775 {
3776 	int u2del, besl, besl_host;
3777 	int besl_device = 0;
3778 	u32 field;
3779 
3780 	u2del = HCS_U2_LATENCY(xhci->hcs_params3);
3781 	field = le32_to_cpu(udev->bos->ext_cap->bmAttributes);
3782 
3783 	if (field & USB_BESL_SUPPORT) {
3784 		for (besl_host = 0; besl_host < 16; besl_host++) {
3785 			if (xhci_besl_encoding[besl_host] >= u2del)
3786 				break;
3787 		}
3788 		/* Use baseline BESL value as default */
3789 		if (field & USB_BESL_BASELINE_VALID)
3790 			besl_device = USB_GET_BESL_BASELINE(field);
3791 		else if (field & USB_BESL_DEEP_VALID)
3792 			besl_device = USB_GET_BESL_DEEP(field);
3793 	} else {
3794 		if (u2del <= 50)
3795 			besl_host = 0;
3796 		else
3797 			besl_host = (u2del - 51) / 75 + 1;
3798 	}
3799 
3800 	besl = besl_host + besl_device;
3801 	if (besl > 15)
3802 		besl = 15;
3803 
3804 	return besl;
3805 }
3806 
3807 static int xhci_usb2_software_lpm_test(struct usb_hcd *hcd,
3808 					struct usb_device *udev)
3809 {
3810 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
3811 	struct dev_info	*dev_info;
3812 	__le32 __iomem	**port_array;
3813 	__le32 __iomem	*addr, *pm_addr;
3814 	u32		temp, dev_id;
3815 	unsigned int	port_num;
3816 	unsigned long	flags;
3817 	int		hird;
3818 	int		ret;
3819 
3820 	if (hcd->speed == HCD_USB3 || !xhci->sw_lpm_support ||
3821 			!udev->lpm_capable)
3822 		return -EINVAL;
3823 
3824 	/* we only support lpm for non-hub device connected to root hub yet */
3825 	if (!udev->parent || udev->parent->parent ||
3826 			udev->descriptor.bDeviceClass == USB_CLASS_HUB)
3827 		return -EINVAL;
3828 
3829 	spin_lock_irqsave(&xhci->lock, flags);
3830 
3831 	/* Look for devices in lpm_failed_devs list */
3832 	dev_id = le16_to_cpu(udev->descriptor.idVendor) << 16 |
3833 			le16_to_cpu(udev->descriptor.idProduct);
3834 	list_for_each_entry(dev_info, &xhci->lpm_failed_devs, list) {
3835 		if (dev_info->dev_id == dev_id) {
3836 			ret = -EINVAL;
3837 			goto finish;
3838 		}
3839 	}
3840 
3841 	port_array = xhci->usb2_ports;
3842 	port_num = udev->portnum - 1;
3843 
3844 	if (port_num > HCS_MAX_PORTS(xhci->hcs_params1)) {
3845 		xhci_dbg(xhci, "invalid port number %d\n", udev->portnum);
3846 		ret = -EINVAL;
3847 		goto finish;
3848 	}
3849 
3850 	/*
3851 	 * Test USB 2.0 software LPM.
3852 	 * FIXME: some xHCI 1.0 hosts may implement a new register to set up
3853 	 * hardware-controlled USB 2.0 LPM. See section 5.4.11 and 4.23.5.1.1.1
3854 	 * in the June 2011 errata release.
3855 	 */
3856 	xhci_dbg(xhci, "test port %d software LPM\n", port_num);
3857 	/*
3858 	 * Set L1 Device Slot and HIRD/BESL.
3859 	 * Check device's USB 2.0 extension descriptor to determine whether
3860 	 * HIRD or BESL shoule be used. See USB2.0 LPM errata.
3861 	 */
3862 	pm_addr = port_array[port_num] + 1;
3863 	hird = xhci_calculate_hird_besl(xhci, udev);
3864 	temp = PORT_L1DS(udev->slot_id) | PORT_HIRD(hird);
3865 	xhci_writel(xhci, temp, pm_addr);
3866 
3867 	/* Set port link state to U2(L1) */
3868 	addr = port_array[port_num];
3869 	xhci_set_link_state(xhci, port_array, port_num, XDEV_U2);
3870 
3871 	/* wait for ACK */
3872 	spin_unlock_irqrestore(&xhci->lock, flags);
3873 	msleep(10);
3874 	spin_lock_irqsave(&xhci->lock, flags);
3875 
3876 	/* Check L1 Status */
3877 	ret = handshake(xhci, pm_addr, PORT_L1S_MASK, PORT_L1S_SUCCESS, 125);
3878 	if (ret != -ETIMEDOUT) {
3879 		/* enter L1 successfully */
3880 		temp = xhci_readl(xhci, addr);
3881 		xhci_dbg(xhci, "port %d entered L1 state, port status 0x%x\n",
3882 				port_num, temp);
3883 		ret = 0;
3884 	} else {
3885 		temp = xhci_readl(xhci, pm_addr);
3886 		xhci_dbg(xhci, "port %d software lpm failed, L1 status %d\n",
3887 				port_num, temp & PORT_L1S_MASK);
3888 		ret = -EINVAL;
3889 	}
3890 
3891 	/* Resume the port */
3892 	xhci_set_link_state(xhci, port_array, port_num, XDEV_U0);
3893 
3894 	spin_unlock_irqrestore(&xhci->lock, flags);
3895 	msleep(10);
3896 	spin_lock_irqsave(&xhci->lock, flags);
3897 
3898 	/* Clear PLC */
3899 	xhci_test_and_clear_bit(xhci, port_array, port_num, PORT_PLC);
3900 
3901 	/* Check PORTSC to make sure the device is in the right state */
3902 	if (!ret) {
3903 		temp = xhci_readl(xhci, addr);
3904 		xhci_dbg(xhci, "resumed port %d status 0x%x\n",	port_num, temp);
3905 		if (!(temp & PORT_CONNECT) || !(temp & PORT_PE) ||
3906 				(temp & PORT_PLS_MASK) != XDEV_U0) {
3907 			xhci_dbg(xhci, "port L1 resume fail\n");
3908 			ret = -EINVAL;
3909 		}
3910 	}
3911 
3912 	if (ret) {
3913 		/* Insert dev to lpm_failed_devs list */
3914 		xhci_warn(xhci, "device LPM test failed, may disconnect and "
3915 				"re-enumerate\n");
3916 		dev_info = kzalloc(sizeof(struct dev_info), GFP_ATOMIC);
3917 		if (!dev_info) {
3918 			ret = -ENOMEM;
3919 			goto finish;
3920 		}
3921 		dev_info->dev_id = dev_id;
3922 		INIT_LIST_HEAD(&dev_info->list);
3923 		list_add(&dev_info->list, &xhci->lpm_failed_devs);
3924 	} else {
3925 		xhci_ring_device(xhci, udev->slot_id);
3926 	}
3927 
3928 finish:
3929 	spin_unlock_irqrestore(&xhci->lock, flags);
3930 	return ret;
3931 }
3932 
3933 int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd,
3934 			struct usb_device *udev, int enable)
3935 {
3936 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
3937 	__le32 __iomem	**port_array;
3938 	__le32 __iomem	*pm_addr;
3939 	u32		temp;
3940 	unsigned int	port_num;
3941 	unsigned long	flags;
3942 	int		hird;
3943 
3944 	if (hcd->speed == HCD_USB3 || !xhci->hw_lpm_support ||
3945 			!udev->lpm_capable)
3946 		return -EPERM;
3947 
3948 	if (!udev->parent || udev->parent->parent ||
3949 			udev->descriptor.bDeviceClass == USB_CLASS_HUB)
3950 		return -EPERM;
3951 
3952 	if (udev->usb2_hw_lpm_capable != 1)
3953 		return -EPERM;
3954 
3955 	spin_lock_irqsave(&xhci->lock, flags);
3956 
3957 	port_array = xhci->usb2_ports;
3958 	port_num = udev->portnum - 1;
3959 	pm_addr = port_array[port_num] + 1;
3960 	temp = xhci_readl(xhci, pm_addr);
3961 
3962 	xhci_dbg(xhci, "%s port %d USB2 hardware LPM\n",
3963 			enable ? "enable" : "disable", port_num);
3964 
3965 	hird = xhci_calculate_hird_besl(xhci, udev);
3966 
3967 	if (enable) {
3968 		temp &= ~PORT_HIRD_MASK;
3969 		temp |= PORT_HIRD(hird) | PORT_RWE;
3970 		xhci_writel(xhci, temp, pm_addr);
3971 		temp = xhci_readl(xhci, pm_addr);
3972 		temp |= PORT_HLE;
3973 		xhci_writel(xhci, temp, pm_addr);
3974 	} else {
3975 		temp &= ~(PORT_HLE | PORT_RWE | PORT_HIRD_MASK);
3976 		xhci_writel(xhci, temp, pm_addr);
3977 	}
3978 
3979 	spin_unlock_irqrestore(&xhci->lock, flags);
3980 	return 0;
3981 }
3982 
3983 int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
3984 {
3985 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
3986 	int		ret;
3987 
3988 	ret = xhci_usb2_software_lpm_test(hcd, udev);
3989 	if (!ret) {
3990 		xhci_dbg(xhci, "software LPM test succeed\n");
3991 		if (xhci->hw_lpm_support == 1) {
3992 			udev->usb2_hw_lpm_capable = 1;
3993 			ret = xhci_set_usb2_hardware_lpm(hcd, udev, 1);
3994 			if (!ret)
3995 				udev->usb2_hw_lpm_enabled = 1;
3996 		}
3997 	}
3998 
3999 	return 0;
4000 }
4001 
4002 #else
4003 
4004 int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd,
4005 				struct usb_device *udev, int enable)
4006 {
4007 	return 0;
4008 }
4009 
4010 int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
4011 {
4012 	return 0;
4013 }
4014 
4015 #endif /* CONFIG_USB_SUSPEND */
4016 
4017 /*---------------------- USB 3.0 Link PM functions ------------------------*/
4018 
4019 #ifdef CONFIG_PM
4020 /* Service interval in nanoseconds = 2^(bInterval - 1) * 125us * 1000ns / 1us */
4021 static unsigned long long xhci_service_interval_to_ns(
4022 		struct usb_endpoint_descriptor *desc)
4023 {
4024 	return (1ULL << (desc->bInterval - 1)) * 125 * 1000;
4025 }
4026 
4027 static u16 xhci_get_timeout_no_hub_lpm(struct usb_device *udev,
4028 		enum usb3_link_state state)
4029 {
4030 	unsigned long long sel;
4031 	unsigned long long pel;
4032 	unsigned int max_sel_pel;
4033 	char *state_name;
4034 
4035 	switch (state) {
4036 	case USB3_LPM_U1:
4037 		/* Convert SEL and PEL stored in nanoseconds to microseconds */
4038 		sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4039 		pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
4040 		max_sel_pel = USB3_LPM_MAX_U1_SEL_PEL;
4041 		state_name = "U1";
4042 		break;
4043 	case USB3_LPM_U2:
4044 		sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4045 		pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
4046 		max_sel_pel = USB3_LPM_MAX_U2_SEL_PEL;
4047 		state_name = "U2";
4048 		break;
4049 	default:
4050 		dev_warn(&udev->dev, "%s: Can't get timeout for non-U1 or U2 state.\n",
4051 				__func__);
4052 		return USB3_LPM_DISABLED;
4053 	}
4054 
4055 	if (sel <= max_sel_pel && pel <= max_sel_pel)
4056 		return USB3_LPM_DEVICE_INITIATED;
4057 
4058 	if (sel > max_sel_pel)
4059 		dev_dbg(&udev->dev, "Device-initiated %s disabled "
4060 				"due to long SEL %llu ms\n",
4061 				state_name, sel);
4062 	else
4063 		dev_dbg(&udev->dev, "Device-initiated %s disabled "
4064 				"due to long PEL %llu\n ms",
4065 				state_name, pel);
4066 	return USB3_LPM_DISABLED;
4067 }
4068 
4069 /* Returns the hub-encoded U1 timeout value.
4070  * The U1 timeout should be the maximum of the following values:
4071  *  - For control endpoints, U1 system exit latency (SEL) * 3
4072  *  - For bulk endpoints, U1 SEL * 5
4073  *  - For interrupt endpoints:
4074  *    - Notification EPs, U1 SEL * 3
4075  *    - Periodic EPs, max(105% of bInterval, U1 SEL * 2)
4076  *  - For isochronous endpoints, max(105% of bInterval, U1 SEL * 2)
4077  */
4078 static u16 xhci_calculate_intel_u1_timeout(struct usb_device *udev,
4079 		struct usb_endpoint_descriptor *desc)
4080 {
4081 	unsigned long long timeout_ns;
4082 	int ep_type;
4083 	int intr_type;
4084 
4085 	ep_type = usb_endpoint_type(desc);
4086 	switch (ep_type) {
4087 	case USB_ENDPOINT_XFER_CONTROL:
4088 		timeout_ns = udev->u1_params.sel * 3;
4089 		break;
4090 	case USB_ENDPOINT_XFER_BULK:
4091 		timeout_ns = udev->u1_params.sel * 5;
4092 		break;
4093 	case USB_ENDPOINT_XFER_INT:
4094 		intr_type = usb_endpoint_interrupt_type(desc);
4095 		if (intr_type == USB_ENDPOINT_INTR_NOTIFICATION) {
4096 			timeout_ns = udev->u1_params.sel * 3;
4097 			break;
4098 		}
4099 		/* Otherwise the calculation is the same as isoc eps */
4100 	case USB_ENDPOINT_XFER_ISOC:
4101 		timeout_ns = xhci_service_interval_to_ns(desc);
4102 		timeout_ns = DIV_ROUND_UP_ULL(timeout_ns * 105, 100);
4103 		if (timeout_ns < udev->u1_params.sel * 2)
4104 			timeout_ns = udev->u1_params.sel * 2;
4105 		break;
4106 	default:
4107 		return 0;
4108 	}
4109 
4110 	/* The U1 timeout is encoded in 1us intervals. */
4111 	timeout_ns = DIV_ROUND_UP_ULL(timeout_ns, 1000);
4112 	/* Don't return a timeout of zero, because that's USB3_LPM_DISABLED. */
4113 	if (timeout_ns == USB3_LPM_DISABLED)
4114 		timeout_ns++;
4115 
4116 	/* If the necessary timeout value is bigger than what we can set in the
4117 	 * USB 3.0 hub, we have to disable hub-initiated U1.
4118 	 */
4119 	if (timeout_ns <= USB3_LPM_U1_MAX_TIMEOUT)
4120 		return timeout_ns;
4121 	dev_dbg(&udev->dev, "Hub-initiated U1 disabled "
4122 			"due to long timeout %llu ms\n", timeout_ns);
4123 	return xhci_get_timeout_no_hub_lpm(udev, USB3_LPM_U1);
4124 }
4125 
4126 /* Returns the hub-encoded U2 timeout value.
4127  * The U2 timeout should be the maximum of:
4128  *  - 10 ms (to avoid the bandwidth impact on the scheduler)
4129  *  - largest bInterval of any active periodic endpoint (to avoid going
4130  *    into lower power link states between intervals).
4131  *  - the U2 Exit Latency of the device
4132  */
4133 static u16 xhci_calculate_intel_u2_timeout(struct usb_device *udev,
4134 		struct usb_endpoint_descriptor *desc)
4135 {
4136 	unsigned long long timeout_ns;
4137 	unsigned long long u2_del_ns;
4138 
4139 	timeout_ns = 10 * 1000 * 1000;
4140 
4141 	if ((usb_endpoint_xfer_int(desc) || usb_endpoint_xfer_isoc(desc)) &&
4142 			(xhci_service_interval_to_ns(desc) > timeout_ns))
4143 		timeout_ns = xhci_service_interval_to_ns(desc);
4144 
4145 	u2_del_ns = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat) * 1000ULL;
4146 	if (u2_del_ns > timeout_ns)
4147 		timeout_ns = u2_del_ns;
4148 
4149 	/* The U2 timeout is encoded in 256us intervals */
4150 	timeout_ns = DIV_ROUND_UP_ULL(timeout_ns, 256 * 1000);
4151 	/* If the necessary timeout value is bigger than what we can set in the
4152 	 * USB 3.0 hub, we have to disable hub-initiated U2.
4153 	 */
4154 	if (timeout_ns <= USB3_LPM_U2_MAX_TIMEOUT)
4155 		return timeout_ns;
4156 	dev_dbg(&udev->dev, "Hub-initiated U2 disabled "
4157 			"due to long timeout %llu ms\n", timeout_ns);
4158 	return xhci_get_timeout_no_hub_lpm(udev, USB3_LPM_U2);
4159 }
4160 
4161 static u16 xhci_call_host_update_timeout_for_endpoint(struct xhci_hcd *xhci,
4162 		struct usb_device *udev,
4163 		struct usb_endpoint_descriptor *desc,
4164 		enum usb3_link_state state,
4165 		u16 *timeout)
4166 {
4167 	if (state == USB3_LPM_U1) {
4168 		if (xhci->quirks & XHCI_INTEL_HOST)
4169 			return xhci_calculate_intel_u1_timeout(udev, desc);
4170 	} else {
4171 		if (xhci->quirks & XHCI_INTEL_HOST)
4172 			return xhci_calculate_intel_u2_timeout(udev, desc);
4173 	}
4174 
4175 	return USB3_LPM_DISABLED;
4176 }
4177 
4178 static int xhci_update_timeout_for_endpoint(struct xhci_hcd *xhci,
4179 		struct usb_device *udev,
4180 		struct usb_endpoint_descriptor *desc,
4181 		enum usb3_link_state state,
4182 		u16 *timeout)
4183 {
4184 	u16 alt_timeout;
4185 
4186 	alt_timeout = xhci_call_host_update_timeout_for_endpoint(xhci, udev,
4187 		desc, state, timeout);
4188 
4189 	/* If we found we can't enable hub-initiated LPM, or
4190 	 * the U1 or U2 exit latency was too high to allow
4191 	 * device-initiated LPM as well, just stop searching.
4192 	 */
4193 	if (alt_timeout == USB3_LPM_DISABLED ||
4194 			alt_timeout == USB3_LPM_DEVICE_INITIATED) {
4195 		*timeout = alt_timeout;
4196 		return -E2BIG;
4197 	}
4198 	if (alt_timeout > *timeout)
4199 		*timeout = alt_timeout;
4200 	return 0;
4201 }
4202 
4203 static int xhci_update_timeout_for_interface(struct xhci_hcd *xhci,
4204 		struct usb_device *udev,
4205 		struct usb_host_interface *alt,
4206 		enum usb3_link_state state,
4207 		u16 *timeout)
4208 {
4209 	int j;
4210 
4211 	for (j = 0; j < alt->desc.bNumEndpoints; j++) {
4212 		if (xhci_update_timeout_for_endpoint(xhci, udev,
4213 					&alt->endpoint[j].desc, state, timeout))
4214 			return -E2BIG;
4215 		continue;
4216 	}
4217 	return 0;
4218 }
4219 
4220 static int xhci_check_intel_tier_policy(struct usb_device *udev,
4221 		enum usb3_link_state state)
4222 {
4223 	struct usb_device *parent;
4224 	unsigned int num_hubs;
4225 
4226 	if (state == USB3_LPM_U2)
4227 		return 0;
4228 
4229 	/* Don't enable U1 if the device is on a 2nd tier hub or lower. */
4230 	for (parent = udev->parent, num_hubs = 0; parent->parent;
4231 			parent = parent->parent)
4232 		num_hubs++;
4233 
4234 	if (num_hubs < 2)
4235 		return 0;
4236 
4237 	dev_dbg(&udev->dev, "Disabling U1 link state for device"
4238 			" below second-tier hub.\n");
4239 	dev_dbg(&udev->dev, "Plug device into first-tier hub "
4240 			"to decrease power consumption.\n");
4241 	return -E2BIG;
4242 }
4243 
4244 static int xhci_check_tier_policy(struct xhci_hcd *xhci,
4245 		struct usb_device *udev,
4246 		enum usb3_link_state state)
4247 {
4248 	if (xhci->quirks & XHCI_INTEL_HOST)
4249 		return xhci_check_intel_tier_policy(udev, state);
4250 	return -EINVAL;
4251 }
4252 
4253 /* Returns the U1 or U2 timeout that should be enabled.
4254  * If the tier check or timeout setting functions return with a non-zero exit
4255  * code, that means the timeout value has been finalized and we shouldn't look
4256  * at any more endpoints.
4257  */
4258 static u16 xhci_calculate_lpm_timeout(struct usb_hcd *hcd,
4259 			struct usb_device *udev, enum usb3_link_state state)
4260 {
4261 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
4262 	struct usb_host_config *config;
4263 	char *state_name;
4264 	int i;
4265 	u16 timeout = USB3_LPM_DISABLED;
4266 
4267 	if (state == USB3_LPM_U1)
4268 		state_name = "U1";
4269 	else if (state == USB3_LPM_U2)
4270 		state_name = "U2";
4271 	else {
4272 		dev_warn(&udev->dev, "Can't enable unknown link state %i\n",
4273 				state);
4274 		return timeout;
4275 	}
4276 
4277 	if (xhci_check_tier_policy(xhci, udev, state) < 0)
4278 		return timeout;
4279 
4280 	/* Gather some information about the currently installed configuration
4281 	 * and alternate interface settings.
4282 	 */
4283 	if (xhci_update_timeout_for_endpoint(xhci, udev, &udev->ep0.desc,
4284 			state, &timeout))
4285 		return timeout;
4286 
4287 	config = udev->actconfig;
4288 	if (!config)
4289 		return timeout;
4290 
4291 	for (i = 0; i < USB_MAXINTERFACES; i++) {
4292 		struct usb_driver *driver;
4293 		struct usb_interface *intf = config->interface[i];
4294 
4295 		if (!intf)
4296 			continue;
4297 
4298 		/* Check if any currently bound drivers want hub-initiated LPM
4299 		 * disabled.
4300 		 */
4301 		if (intf->dev.driver) {
4302 			driver = to_usb_driver(intf->dev.driver);
4303 			if (driver && driver->disable_hub_initiated_lpm) {
4304 				dev_dbg(&udev->dev, "Hub-initiated %s disabled "
4305 						"at request of driver %s\n",
4306 						state_name, driver->name);
4307 				return xhci_get_timeout_no_hub_lpm(udev, state);
4308 			}
4309 		}
4310 
4311 		/* Not sure how this could happen... */
4312 		if (!intf->cur_altsetting)
4313 			continue;
4314 
4315 		if (xhci_update_timeout_for_interface(xhci, udev,
4316 					intf->cur_altsetting,
4317 					state, &timeout))
4318 			return timeout;
4319 	}
4320 	return timeout;
4321 }
4322 
4323 /*
4324  * Issue an Evaluate Context command to change the Maximum Exit Latency in the
4325  * slot context.  If that succeeds, store the new MEL in the xhci_virt_device.
4326  */
4327 static int xhci_change_max_exit_latency(struct xhci_hcd *xhci,
4328 			struct usb_device *udev, u16 max_exit_latency)
4329 {
4330 	struct xhci_virt_device *virt_dev;
4331 	struct xhci_command *command;
4332 	struct xhci_input_control_ctx *ctrl_ctx;
4333 	struct xhci_slot_ctx *slot_ctx;
4334 	unsigned long flags;
4335 	int ret;
4336 
4337 	spin_lock_irqsave(&xhci->lock, flags);
4338 	if (max_exit_latency == xhci->devs[udev->slot_id]->current_mel) {
4339 		spin_unlock_irqrestore(&xhci->lock, flags);
4340 		return 0;
4341 	}
4342 
4343 	/* Attempt to issue an Evaluate Context command to change the MEL. */
4344 	virt_dev = xhci->devs[udev->slot_id];
4345 	command = xhci->lpm_command;
4346 	xhci_slot_copy(xhci, command->in_ctx, virt_dev->out_ctx);
4347 	spin_unlock_irqrestore(&xhci->lock, flags);
4348 
4349 	ctrl_ctx = xhci_get_input_control_ctx(xhci, command->in_ctx);
4350 	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
4351 	slot_ctx = xhci_get_slot_ctx(xhci, command->in_ctx);
4352 	slot_ctx->dev_info2 &= cpu_to_le32(~((u32) MAX_EXIT));
4353 	slot_ctx->dev_info2 |= cpu_to_le32(max_exit_latency);
4354 
4355 	xhci_dbg(xhci, "Set up evaluate context for LPM MEL change.\n");
4356 	xhci_dbg(xhci, "Slot %u Input Context:\n", udev->slot_id);
4357 	xhci_dbg_ctx(xhci, command->in_ctx, 0);
4358 
4359 	/* Issue and wait for the evaluate context command. */
4360 	ret = xhci_configure_endpoint(xhci, udev, command,
4361 			true, true);
4362 	xhci_dbg(xhci, "Slot %u Output Context:\n", udev->slot_id);
4363 	xhci_dbg_ctx(xhci, virt_dev->out_ctx, 0);
4364 
4365 	if (!ret) {
4366 		spin_lock_irqsave(&xhci->lock, flags);
4367 		virt_dev->current_mel = max_exit_latency;
4368 		spin_unlock_irqrestore(&xhci->lock, flags);
4369 	}
4370 	return ret;
4371 }
4372 
4373 static int calculate_max_exit_latency(struct usb_device *udev,
4374 		enum usb3_link_state state_changed,
4375 		u16 hub_encoded_timeout)
4376 {
4377 	unsigned long long u1_mel_us = 0;
4378 	unsigned long long u2_mel_us = 0;
4379 	unsigned long long mel_us = 0;
4380 	bool disabling_u1;
4381 	bool disabling_u2;
4382 	bool enabling_u1;
4383 	bool enabling_u2;
4384 
4385 	disabling_u1 = (state_changed == USB3_LPM_U1 &&
4386 			hub_encoded_timeout == USB3_LPM_DISABLED);
4387 	disabling_u2 = (state_changed == USB3_LPM_U2 &&
4388 			hub_encoded_timeout == USB3_LPM_DISABLED);
4389 
4390 	enabling_u1 = (state_changed == USB3_LPM_U1 &&
4391 			hub_encoded_timeout != USB3_LPM_DISABLED);
4392 	enabling_u2 = (state_changed == USB3_LPM_U2 &&
4393 			hub_encoded_timeout != USB3_LPM_DISABLED);
4394 
4395 	/* If U1 was already enabled and we're not disabling it,
4396 	 * or we're going to enable U1, account for the U1 max exit latency.
4397 	 */
4398 	if ((udev->u1_params.timeout != USB3_LPM_DISABLED && !disabling_u1) ||
4399 			enabling_u1)
4400 		u1_mel_us = DIV_ROUND_UP(udev->u1_params.mel, 1000);
4401 	if ((udev->u2_params.timeout != USB3_LPM_DISABLED && !disabling_u2) ||
4402 			enabling_u2)
4403 		u2_mel_us = DIV_ROUND_UP(udev->u2_params.mel, 1000);
4404 
4405 	if (u1_mel_us > u2_mel_us)
4406 		mel_us = u1_mel_us;
4407 	else
4408 		mel_us = u2_mel_us;
4409 	/* xHCI host controller max exit latency field is only 16 bits wide. */
4410 	if (mel_us > MAX_EXIT) {
4411 		dev_warn(&udev->dev, "Link PM max exit latency of %lluus "
4412 				"is too big.\n", mel_us);
4413 		return -E2BIG;
4414 	}
4415 	return mel_us;
4416 }
4417 
4418 /* Returns the USB3 hub-encoded value for the U1/U2 timeout. */
4419 int xhci_enable_usb3_lpm_timeout(struct usb_hcd *hcd,
4420 			struct usb_device *udev, enum usb3_link_state state)
4421 {
4422 	struct xhci_hcd	*xhci;
4423 	u16 hub_encoded_timeout;
4424 	int mel;
4425 	int ret;
4426 
4427 	xhci = hcd_to_xhci(hcd);
4428 	/* The LPM timeout values are pretty host-controller specific, so don't
4429 	 * enable hub-initiated timeouts unless the vendor has provided
4430 	 * information about their timeout algorithm.
4431 	 */
4432 	if (!xhci || !(xhci->quirks & XHCI_LPM_SUPPORT) ||
4433 			!xhci->devs[udev->slot_id])
4434 		return USB3_LPM_DISABLED;
4435 
4436 	hub_encoded_timeout = xhci_calculate_lpm_timeout(hcd, udev, state);
4437 	mel = calculate_max_exit_latency(udev, state, hub_encoded_timeout);
4438 	if (mel < 0) {
4439 		/* Max Exit Latency is too big, disable LPM. */
4440 		hub_encoded_timeout = USB3_LPM_DISABLED;
4441 		mel = 0;
4442 	}
4443 
4444 	ret = xhci_change_max_exit_latency(xhci, udev, mel);
4445 	if (ret)
4446 		return ret;
4447 	return hub_encoded_timeout;
4448 }
4449 
4450 int xhci_disable_usb3_lpm_timeout(struct usb_hcd *hcd,
4451 			struct usb_device *udev, enum usb3_link_state state)
4452 {
4453 	struct xhci_hcd	*xhci;
4454 	u16 mel;
4455 	int ret;
4456 
4457 	xhci = hcd_to_xhci(hcd);
4458 	if (!xhci || !(xhci->quirks & XHCI_LPM_SUPPORT) ||
4459 			!xhci->devs[udev->slot_id])
4460 		return 0;
4461 
4462 	mel = calculate_max_exit_latency(udev, state, USB3_LPM_DISABLED);
4463 	ret = xhci_change_max_exit_latency(xhci, udev, mel);
4464 	if (ret)
4465 		return ret;
4466 	return 0;
4467 }
4468 #else /* CONFIG_PM */
4469 
4470 int xhci_enable_usb3_lpm_timeout(struct usb_hcd *hcd,
4471 			struct usb_device *udev, enum usb3_link_state state)
4472 {
4473 	return USB3_LPM_DISABLED;
4474 }
4475 
4476 int xhci_disable_usb3_lpm_timeout(struct usb_hcd *hcd,
4477 			struct usb_device *udev, enum usb3_link_state state)
4478 {
4479 	return 0;
4480 }
4481 #endif	/* CONFIG_PM */
4482 
4483 /*-------------------------------------------------------------------------*/
4484 
4485 /* Once a hub descriptor is fetched for a device, we need to update the xHC's
4486  * internal data structures for the device.
4487  */
4488 int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
4489 			struct usb_tt *tt, gfp_t mem_flags)
4490 {
4491 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
4492 	struct xhci_virt_device *vdev;
4493 	struct xhci_command *config_cmd;
4494 	struct xhci_input_control_ctx *ctrl_ctx;
4495 	struct xhci_slot_ctx *slot_ctx;
4496 	unsigned long flags;
4497 	unsigned think_time;
4498 	int ret;
4499 
4500 	/* Ignore root hubs */
4501 	if (!hdev->parent)
4502 		return 0;
4503 
4504 	vdev = xhci->devs[hdev->slot_id];
4505 	if (!vdev) {
4506 		xhci_warn(xhci, "Cannot update hub desc for unknown device.\n");
4507 		return -EINVAL;
4508 	}
4509 	config_cmd = xhci_alloc_command(xhci, true, true, mem_flags);
4510 	if (!config_cmd) {
4511 		xhci_dbg(xhci, "Could not allocate xHCI command structure.\n");
4512 		return -ENOMEM;
4513 	}
4514 
4515 	spin_lock_irqsave(&xhci->lock, flags);
4516 	if (hdev->speed == USB_SPEED_HIGH &&
4517 			xhci_alloc_tt_info(xhci, vdev, hdev, tt, GFP_ATOMIC)) {
4518 		xhci_dbg(xhci, "Could not allocate xHCI TT structure.\n");
4519 		xhci_free_command(xhci, config_cmd);
4520 		spin_unlock_irqrestore(&xhci->lock, flags);
4521 		return -ENOMEM;
4522 	}
4523 
4524 	xhci_slot_copy(xhci, config_cmd->in_ctx, vdev->out_ctx);
4525 	ctrl_ctx = xhci_get_input_control_ctx(xhci, config_cmd->in_ctx);
4526 	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
4527 	slot_ctx = xhci_get_slot_ctx(xhci, config_cmd->in_ctx);
4528 	slot_ctx->dev_info |= cpu_to_le32(DEV_HUB);
4529 	if (tt->multi)
4530 		slot_ctx->dev_info |= cpu_to_le32(DEV_MTT);
4531 	if (xhci->hci_version > 0x95) {
4532 		xhci_dbg(xhci, "xHCI version %x needs hub "
4533 				"TT think time and number of ports\n",
4534 				(unsigned int) xhci->hci_version);
4535 		slot_ctx->dev_info2 |= cpu_to_le32(XHCI_MAX_PORTS(hdev->maxchild));
4536 		/* Set TT think time - convert from ns to FS bit times.
4537 		 * 0 = 8 FS bit times, 1 = 16 FS bit times,
4538 		 * 2 = 24 FS bit times, 3 = 32 FS bit times.
4539 		 *
4540 		 * xHCI 1.0: this field shall be 0 if the device is not a
4541 		 * High-spped hub.
4542 		 */
4543 		think_time = tt->think_time;
4544 		if (think_time != 0)
4545 			think_time = (think_time / 666) - 1;
4546 		if (xhci->hci_version < 0x100 || hdev->speed == USB_SPEED_HIGH)
4547 			slot_ctx->tt_info |=
4548 				cpu_to_le32(TT_THINK_TIME(think_time));
4549 	} else {
4550 		xhci_dbg(xhci, "xHCI version %x doesn't need hub "
4551 				"TT think time or number of ports\n",
4552 				(unsigned int) xhci->hci_version);
4553 	}
4554 	slot_ctx->dev_state = 0;
4555 	spin_unlock_irqrestore(&xhci->lock, flags);
4556 
4557 	xhci_dbg(xhci, "Set up %s for hub device.\n",
4558 			(xhci->hci_version > 0x95) ?
4559 			"configure endpoint" : "evaluate context");
4560 	xhci_dbg(xhci, "Slot %u Input Context:\n", hdev->slot_id);
4561 	xhci_dbg_ctx(xhci, config_cmd->in_ctx, 0);
4562 
4563 	/* Issue and wait for the configure endpoint or
4564 	 * evaluate context command.
4565 	 */
4566 	if (xhci->hci_version > 0x95)
4567 		ret = xhci_configure_endpoint(xhci, hdev, config_cmd,
4568 				false, false);
4569 	else
4570 		ret = xhci_configure_endpoint(xhci, hdev, config_cmd,
4571 				true, false);
4572 
4573 	xhci_dbg(xhci, "Slot %u Output Context:\n", hdev->slot_id);
4574 	xhci_dbg_ctx(xhci, vdev->out_ctx, 0);
4575 
4576 	xhci_free_command(xhci, config_cmd);
4577 	return ret;
4578 }
4579 
4580 int xhci_get_frame(struct usb_hcd *hcd)
4581 {
4582 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
4583 	/* EHCI mods by the periodic size.  Why? */
4584 	return xhci_readl(xhci, &xhci->run_regs->microframe_index) >> 3;
4585 }
4586 
4587 int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
4588 {
4589 	struct xhci_hcd		*xhci;
4590 	struct device		*dev = hcd->self.controller;
4591 	int			retval;
4592 	u32			temp;
4593 
4594 	/* Accept arbitrarily long scatter-gather lists */
4595 	hcd->self.sg_tablesize = ~0;
4596 	/* XHCI controllers don't stop the ep queue on short packets :| */
4597 	hcd->self.no_stop_on_short = 1;
4598 
4599 	if (usb_hcd_is_primary_hcd(hcd)) {
4600 		xhci = kzalloc(sizeof(struct xhci_hcd), GFP_KERNEL);
4601 		if (!xhci)
4602 			return -ENOMEM;
4603 		*((struct xhci_hcd **) hcd->hcd_priv) = xhci;
4604 		xhci->main_hcd = hcd;
4605 		/* Mark the first roothub as being USB 2.0.
4606 		 * The xHCI driver will register the USB 3.0 roothub.
4607 		 */
4608 		hcd->speed = HCD_USB2;
4609 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
4610 		/*
4611 		 * USB 2.0 roothub under xHCI has an integrated TT,
4612 		 * (rate matching hub) as opposed to having an OHCI/UHCI
4613 		 * companion controller.
4614 		 */
4615 		hcd->has_tt = 1;
4616 	} else {
4617 		/* xHCI private pointer was set in xhci_pci_probe for the second
4618 		 * registered roothub.
4619 		 */
4620 		xhci = hcd_to_xhci(hcd);
4621 		temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
4622 		if (HCC_64BIT_ADDR(temp)) {
4623 			xhci_dbg(xhci, "Enabling 64-bit DMA addresses.\n");
4624 			dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64));
4625 		} else {
4626 			dma_set_mask(hcd->self.controller, DMA_BIT_MASK(32));
4627 		}
4628 		return 0;
4629 	}
4630 
4631 	xhci->cap_regs = hcd->regs;
4632 	xhci->op_regs = hcd->regs +
4633 		HC_LENGTH(xhci_readl(xhci, &xhci->cap_regs->hc_capbase));
4634 	xhci->run_regs = hcd->regs +
4635 		(xhci_readl(xhci, &xhci->cap_regs->run_regs_off) & RTSOFF_MASK);
4636 	/* Cache read-only capability registers */
4637 	xhci->hcs_params1 = xhci_readl(xhci, &xhci->cap_regs->hcs_params1);
4638 	xhci->hcs_params2 = xhci_readl(xhci, &xhci->cap_regs->hcs_params2);
4639 	xhci->hcs_params3 = xhci_readl(xhci, &xhci->cap_regs->hcs_params3);
4640 	xhci->hcc_params = xhci_readl(xhci, &xhci->cap_regs->hc_capbase);
4641 	xhci->hci_version = HC_VERSION(xhci->hcc_params);
4642 	xhci->hcc_params = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
4643 	xhci_print_registers(xhci);
4644 
4645 	get_quirks(dev, xhci);
4646 
4647 	/* Make sure the HC is halted. */
4648 	retval = xhci_halt(xhci);
4649 	if (retval)
4650 		goto error;
4651 
4652 	xhci_dbg(xhci, "Resetting HCD\n");
4653 	/* Reset the internal HC memory state and registers. */
4654 	retval = xhci_reset(xhci);
4655 	if (retval)
4656 		goto error;
4657 	xhci_dbg(xhci, "Reset complete\n");
4658 
4659 	temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
4660 	if (HCC_64BIT_ADDR(temp)) {
4661 		xhci_dbg(xhci, "Enabling 64-bit DMA addresses.\n");
4662 		dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64));
4663 	} else {
4664 		dma_set_mask(hcd->self.controller, DMA_BIT_MASK(32));
4665 	}
4666 
4667 	xhci_dbg(xhci, "Calling HCD init\n");
4668 	/* Initialize HCD and host controller data structures. */
4669 	retval = xhci_init(hcd);
4670 	if (retval)
4671 		goto error;
4672 	xhci_dbg(xhci, "Called HCD init\n");
4673 	return 0;
4674 error:
4675 	kfree(xhci);
4676 	return retval;
4677 }
4678 
4679 MODULE_DESCRIPTION(DRIVER_DESC);
4680 MODULE_AUTHOR(DRIVER_AUTHOR);
4681 MODULE_LICENSE("GPL");
4682 
4683 static int __init xhci_hcd_init(void)
4684 {
4685 	int retval;
4686 
4687 	retval = xhci_register_pci();
4688 	if (retval < 0) {
4689 		printk(KERN_DEBUG "Problem registering PCI driver.");
4690 		return retval;
4691 	}
4692 	retval = xhci_register_plat();
4693 	if (retval < 0) {
4694 		printk(KERN_DEBUG "Problem registering platform driver.");
4695 		goto unreg_pci;
4696 	}
4697 	/*
4698 	 * Check the compiler generated sizes of structures that must be laid
4699 	 * out in specific ways for hardware access.
4700 	 */
4701 	BUILD_BUG_ON(sizeof(struct xhci_doorbell_array) != 256*32/8);
4702 	BUILD_BUG_ON(sizeof(struct xhci_slot_ctx) != 8*32/8);
4703 	BUILD_BUG_ON(sizeof(struct xhci_ep_ctx) != 8*32/8);
4704 	/* xhci_device_control has eight fields, and also
4705 	 * embeds one xhci_slot_ctx and 31 xhci_ep_ctx
4706 	 */
4707 	BUILD_BUG_ON(sizeof(struct xhci_stream_ctx) != 4*32/8);
4708 	BUILD_BUG_ON(sizeof(union xhci_trb) != 4*32/8);
4709 	BUILD_BUG_ON(sizeof(struct xhci_erst_entry) != 4*32/8);
4710 	BUILD_BUG_ON(sizeof(struct xhci_cap_regs) != 7*32/8);
4711 	BUILD_BUG_ON(sizeof(struct xhci_intr_reg) != 8*32/8);
4712 	/* xhci_run_regs has eight fields and embeds 128 xhci_intr_regs */
4713 	BUILD_BUG_ON(sizeof(struct xhci_run_regs) != (8+8*128)*32/8);
4714 	return 0;
4715 unreg_pci:
4716 	xhci_unregister_pci();
4717 	return retval;
4718 }
4719 module_init(xhci_hcd_init);
4720 
4721 static void __exit xhci_hcd_cleanup(void)
4722 {
4723 	xhci_unregister_pci();
4724 	xhci_unregister_plat();
4725 }
4726 module_exit(xhci_hcd_cleanup);
4727