xref: /linux/drivers/usb/host/uhci-hcd.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /*
2  * Universal Host Controller Interface driver for USB.
3  *
4  * Maintainer: Alan Stern <stern@rowland.harvard.edu>
5  *
6  * (C) Copyright 1999 Linus Torvalds
7  * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
8  * (C) Copyright 1999 Randy Dunlap
9  * (C) Copyright 1999 Georg Acher, acher@in.tum.de
10  * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
11  * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
12  * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at
13  * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface
14  *               support from usb-ohci.c by Adam Richter, adam@yggdrasil.com).
15  * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c)
16  * (C) Copyright 2004-2006 Alan Stern, stern@rowland.harvard.edu
17  *
18  * Intel documents this fairly well, and as far as I know there
19  * are no royalties or anything like that, but even so there are
20  * people who decided that they want to do the same thing in a
21  * completely different way.
22  *
23  */
24 
25 #include <linux/module.h>
26 #include <linux/pci.h>
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/delay.h>
30 #include <linux/ioport.h>
31 #include <linux/sched.h>
32 #include <linux/slab.h>
33 #include <linux/errno.h>
34 #include <linux/unistd.h>
35 #include <linux/interrupt.h>
36 #include <linux/spinlock.h>
37 #include <linux/debugfs.h>
38 #include <linux/pm.h>
39 #include <linux/dmapool.h>
40 #include <linux/dma-mapping.h>
41 #include <linux/usb.h>
42 #include <linux/bitops.h>
43 
44 #include <asm/uaccess.h>
45 #include <asm/io.h>
46 #include <asm/irq.h>
47 #include <asm/system.h>
48 
49 #include "../core/hcd.h"
50 #include "uhci-hcd.h"
51 #include "pci-quirks.h"
52 
53 /*
54  * Version Information
55  */
56 #define DRIVER_VERSION "v3.0"
57 #define DRIVER_AUTHOR "Linus 'Frodo Rabbit' Torvalds, Johannes Erdfelt, \
58 Randy Dunlap, Georg Acher, Deti Fliegl, Thomas Sailer, Roman Weissgaerber, \
59 Alan Stern"
60 #define DRIVER_DESC "USB Universal Host Controller Interface driver"
61 
62 /*
63  * debug = 0, no debugging messages
64  * debug = 1, dump failed URBs except for stalls
65  * debug = 2, dump all failed URBs (including stalls)
66  *            show all queues in /debug/uhci/[pci_addr]
67  * debug = 3, show all TDs in URBs when dumping
68  */
69 #ifdef DEBUG
70 #define DEBUG_CONFIGURED	1
71 static int debug = 1;
72 module_param(debug, int, S_IRUGO | S_IWUSR);
73 MODULE_PARM_DESC(debug, "Debug level");
74 
75 #else
76 #define DEBUG_CONFIGURED	0
77 #define debug			0
78 #endif
79 
80 static char *errbuf;
81 #define ERRBUF_LEN    (32 * 1024)
82 
83 static kmem_cache_t *uhci_up_cachep;	/* urb_priv */
84 
85 static void suspend_rh(struct uhci_hcd *uhci, enum uhci_rh_state new_state);
86 static void wakeup_rh(struct uhci_hcd *uhci);
87 static void uhci_get_current_frame_number(struct uhci_hcd *uhci);
88 
89 #include "uhci-debug.c"
90 #include "uhci-q.c"
91 #include "uhci-hub.c"
92 
93 /*
94  * Finish up a host controller reset and update the recorded state.
95  */
96 static void finish_reset(struct uhci_hcd *uhci)
97 {
98 	int port;
99 
100 	/* HCRESET doesn't affect the Suspend, Reset, and Resume Detect
101 	 * bits in the port status and control registers.
102 	 * We have to clear them by hand.
103 	 */
104 	for (port = 0; port < uhci->rh_numports; ++port)
105 		outw(0, uhci->io_addr + USBPORTSC1 + (port * 2));
106 
107 	uhci->port_c_suspend = uhci->resuming_ports = 0;
108 	uhci->rh_state = UHCI_RH_RESET;
109 	uhci->is_stopped = UHCI_IS_STOPPED;
110 	uhci_to_hcd(uhci)->state = HC_STATE_HALT;
111 	uhci_to_hcd(uhci)->poll_rh = 0;
112 
113 	uhci->dead = 0;		/* Full reset resurrects the controller */
114 }
115 
116 /*
117  * Last rites for a defunct/nonfunctional controller
118  * or one we don't want to use any more.
119  */
120 static void uhci_hc_died(struct uhci_hcd *uhci)
121 {
122 	uhci_get_current_frame_number(uhci);
123 	uhci_reset_hc(to_pci_dev(uhci_dev(uhci)), uhci->io_addr);
124 	finish_reset(uhci);
125 	uhci->dead = 1;
126 
127 	/* The current frame may already be partway finished */
128 	++uhci->frame_number;
129 }
130 
131 /*
132  * Initialize a controller that was newly discovered or has lost power
133  * or otherwise been reset while it was suspended.  In none of these cases
134  * can we be sure of its previous state.
135  */
136 static void check_and_reset_hc(struct uhci_hcd *uhci)
137 {
138 	if (uhci_check_and_reset_hc(to_pci_dev(uhci_dev(uhci)), uhci->io_addr))
139 		finish_reset(uhci);
140 }
141 
142 /*
143  * Store the basic register settings needed by the controller.
144  */
145 static void configure_hc(struct uhci_hcd *uhci)
146 {
147 	/* Set the frame length to the default: 1 ms exactly */
148 	outb(USBSOF_DEFAULT, uhci->io_addr + USBSOF);
149 
150 	/* Store the frame list base address */
151 	outl(uhci->frame_dma_handle, uhci->io_addr + USBFLBASEADD);
152 
153 	/* Set the current frame number */
154 	outw(uhci->frame_number & UHCI_MAX_SOF_NUMBER,
155 			uhci->io_addr + USBFRNUM);
156 
157 	/* Mark controller as not halted before we enable interrupts */
158 	uhci_to_hcd(uhci)->state = HC_STATE_SUSPENDED;
159 	mb();
160 
161 	/* Enable PIRQ */
162 	pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP,
163 			USBLEGSUP_DEFAULT);
164 }
165 
166 
167 static int resume_detect_interrupts_are_broken(struct uhci_hcd *uhci)
168 {
169 	int port;
170 
171 	switch (to_pci_dev(uhci_dev(uhci))->vendor) {
172 	    default:
173 		break;
174 
175 	    case PCI_VENDOR_ID_GENESYS:
176 		/* Genesys Logic's GL880S controllers don't generate
177 		 * resume-detect interrupts.
178 		 */
179 		return 1;
180 
181 	    case PCI_VENDOR_ID_INTEL:
182 		/* Some of Intel's USB controllers have a bug that causes
183 		 * resume-detect interrupts if any port has an over-current
184 		 * condition.  To make matters worse, some motherboards
185 		 * hardwire unused USB ports' over-current inputs active!
186 		 * To prevent problems, we will not enable resume-detect
187 		 * interrupts if any ports are OC.
188 		 */
189 		for (port = 0; port < uhci->rh_numports; ++port) {
190 			if (inw(uhci->io_addr + USBPORTSC1 + port * 2) &
191 					USBPORTSC_OC)
192 				return 1;
193 		}
194 		break;
195 	}
196 	return 0;
197 }
198 
199 static void suspend_rh(struct uhci_hcd *uhci, enum uhci_rh_state new_state)
200 __releases(uhci->lock)
201 __acquires(uhci->lock)
202 {
203 	int auto_stop;
204 	int int_enable;
205 
206 	auto_stop = (new_state == UHCI_RH_AUTO_STOPPED);
207 	dev_dbg(&uhci_to_hcd(uhci)->self.root_hub->dev,
208 			"%s%s\n", __FUNCTION__,
209 			(auto_stop ? " (auto-stop)" : ""));
210 
211 	/* If we get a suspend request when we're already auto-stopped
212 	 * then there's nothing to do.
213 	 */
214 	if (uhci->rh_state == UHCI_RH_AUTO_STOPPED) {
215 		uhci->rh_state = new_state;
216 		return;
217 	}
218 
219 	/* Enable resume-detect interrupts if they work.
220 	 * Then enter Global Suspend mode, still configured.
221 	 */
222 	uhci->working_RD = 1;
223 	int_enable = USBINTR_RESUME;
224 	if (resume_detect_interrupts_are_broken(uhci)) {
225 		uhci->working_RD = int_enable = 0;
226 	}
227 	outw(int_enable, uhci->io_addr + USBINTR);
228 	outw(USBCMD_EGSM | USBCMD_CF, uhci->io_addr + USBCMD);
229 	mb();
230 	udelay(5);
231 
232 	/* If we're auto-stopping then no devices have been attached
233 	 * for a while, so there shouldn't be any active URBs and the
234 	 * controller should stop after a few microseconds.  Otherwise
235 	 * we will give the controller one frame to stop.
236 	 */
237 	if (!auto_stop && !(inw(uhci->io_addr + USBSTS) & USBSTS_HCH)) {
238 		uhci->rh_state = UHCI_RH_SUSPENDING;
239 		spin_unlock_irq(&uhci->lock);
240 		msleep(1);
241 		spin_lock_irq(&uhci->lock);
242 		if (uhci->dead)
243 			return;
244 	}
245 	if (!(inw(uhci->io_addr + USBSTS) & USBSTS_HCH))
246 		dev_warn(&uhci_to_hcd(uhci)->self.root_hub->dev,
247 			"Controller not stopped yet!\n");
248 
249 	uhci_get_current_frame_number(uhci);
250 
251 	uhci->rh_state = new_state;
252 	uhci->is_stopped = UHCI_IS_STOPPED;
253 	uhci_to_hcd(uhci)->poll_rh = !int_enable;
254 
255 	uhci_scan_schedule(uhci, NULL);
256 	uhci_fsbr_off(uhci);
257 }
258 
259 static void start_rh(struct uhci_hcd *uhci)
260 {
261 	uhci_to_hcd(uhci)->state = HC_STATE_RUNNING;
262 	uhci->is_stopped = 0;
263 
264 	/* Mark it configured and running with a 64-byte max packet.
265 	 * All interrupts are enabled, even though RESUME won't do anything.
266 	 */
267 	outw(USBCMD_RS | USBCMD_CF | USBCMD_MAXP, uhci->io_addr + USBCMD);
268 	outw(USBINTR_TIMEOUT | USBINTR_RESUME | USBINTR_IOC | USBINTR_SP,
269 			uhci->io_addr + USBINTR);
270 	mb();
271 	uhci->rh_state = UHCI_RH_RUNNING;
272 	uhci_to_hcd(uhci)->poll_rh = 1;
273 }
274 
275 static void wakeup_rh(struct uhci_hcd *uhci)
276 __releases(uhci->lock)
277 __acquires(uhci->lock)
278 {
279 	dev_dbg(&uhci_to_hcd(uhci)->self.root_hub->dev,
280 			"%s%s\n", __FUNCTION__,
281 			uhci->rh_state == UHCI_RH_AUTO_STOPPED ?
282 				" (auto-start)" : "");
283 
284 	/* If we are auto-stopped then no devices are attached so there's
285 	 * no need for wakeup signals.  Otherwise we send Global Resume
286 	 * for 20 ms.
287 	 */
288 	if (uhci->rh_state == UHCI_RH_SUSPENDED) {
289 		uhci->rh_state = UHCI_RH_RESUMING;
290 		outw(USBCMD_FGR | USBCMD_EGSM | USBCMD_CF,
291 				uhci->io_addr + USBCMD);
292 		spin_unlock_irq(&uhci->lock);
293 		msleep(20);
294 		spin_lock_irq(&uhci->lock);
295 		if (uhci->dead)
296 			return;
297 
298 		/* End Global Resume and wait for EOP to be sent */
299 		outw(USBCMD_CF, uhci->io_addr + USBCMD);
300 		mb();
301 		udelay(4);
302 		if (inw(uhci->io_addr + USBCMD) & USBCMD_FGR)
303 			dev_warn(uhci_dev(uhci), "FGR not stopped yet!\n");
304 	}
305 
306 	start_rh(uhci);
307 
308 	/* Restart root hub polling */
309 	mod_timer(&uhci_to_hcd(uhci)->rh_timer, jiffies);
310 }
311 
312 static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs)
313 {
314 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
315 	unsigned short status;
316 	unsigned long flags;
317 
318 	/*
319 	 * Read the interrupt status, and write it back to clear the
320 	 * interrupt cause.  Contrary to the UHCI specification, the
321 	 * "HC Halted" status bit is persistent: it is RO, not R/WC.
322 	 */
323 	status = inw(uhci->io_addr + USBSTS);
324 	if (!(status & ~USBSTS_HCH))	/* shared interrupt, not mine */
325 		return IRQ_NONE;
326 	outw(status, uhci->io_addr + USBSTS);		/* Clear it */
327 
328 	if (status & ~(USBSTS_USBINT | USBSTS_ERROR | USBSTS_RD)) {
329 		if (status & USBSTS_HSE)
330 			dev_err(uhci_dev(uhci), "host system error, "
331 					"PCI problems?\n");
332 		if (status & USBSTS_HCPE)
333 			dev_err(uhci_dev(uhci), "host controller process "
334 					"error, something bad happened!\n");
335 		if (status & USBSTS_HCH) {
336 			spin_lock_irqsave(&uhci->lock, flags);
337 			if (uhci->rh_state >= UHCI_RH_RUNNING) {
338 				dev_err(uhci_dev(uhci),
339 					"host controller halted, "
340 					"very bad!\n");
341 				if (debug > 1 && errbuf) {
342 					/* Print the schedule for debugging */
343 					uhci_sprint_schedule(uhci,
344 							errbuf, ERRBUF_LEN);
345 					lprintk(errbuf);
346 				}
347 				uhci_hc_died(uhci);
348 
349 				/* Force a callback in case there are
350 				 * pending unlinks */
351 				mod_timer(&hcd->rh_timer, jiffies);
352 			}
353 			spin_unlock_irqrestore(&uhci->lock, flags);
354 		}
355 	}
356 
357 	if (status & USBSTS_RD)
358 		usb_hcd_poll_rh_status(hcd);
359 	else {
360 		spin_lock_irqsave(&uhci->lock, flags);
361 		uhci_scan_schedule(uhci, regs);
362 		spin_unlock_irqrestore(&uhci->lock, flags);
363 	}
364 
365 	return IRQ_HANDLED;
366 }
367 
368 /*
369  * Store the current frame number in uhci->frame_number if the controller
370  * is runnning.  Expand from 11 bits (of which we use only 10) to a
371  * full-sized integer.
372  *
373  * Like many other parts of the driver, this code relies on being polled
374  * more than once per second as long as the controller is running.
375  */
376 static void uhci_get_current_frame_number(struct uhci_hcd *uhci)
377 {
378 	if (!uhci->is_stopped) {
379 		unsigned delta;
380 
381 		delta = (inw(uhci->io_addr + USBFRNUM) - uhci->frame_number) &
382 				(UHCI_NUMFRAMES - 1);
383 		uhci->frame_number += delta;
384 	}
385 }
386 
387 /*
388  * De-allocate all resources
389  */
390 static void release_uhci(struct uhci_hcd *uhci)
391 {
392 	int i;
393 
394 	if (DEBUG_CONFIGURED) {
395 		spin_lock_irq(&uhci->lock);
396 		uhci->is_initialized = 0;
397 		spin_unlock_irq(&uhci->lock);
398 
399 		debugfs_remove(uhci->dentry);
400 	}
401 
402 	for (i = 0; i < UHCI_NUM_SKELQH; i++)
403 		uhci_free_qh(uhci, uhci->skelqh[i]);
404 
405 	uhci_free_td(uhci, uhci->term_td);
406 
407 	dma_pool_destroy(uhci->qh_pool);
408 
409 	dma_pool_destroy(uhci->td_pool);
410 
411 	kfree(uhci->frame_cpu);
412 
413 	dma_free_coherent(uhci_dev(uhci),
414 			UHCI_NUMFRAMES * sizeof(*uhci->frame),
415 			uhci->frame, uhci->frame_dma_handle);
416 }
417 
418 static int uhci_init(struct usb_hcd *hcd)
419 {
420 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
421 	unsigned io_size = (unsigned) hcd->rsrc_len;
422 	int port;
423 
424 	uhci->io_addr = (unsigned long) hcd->rsrc_start;
425 
426 	/* The UHCI spec says devices must have 2 ports, and goes on to say
427 	 * they may have more but gives no way to determine how many there
428 	 * are.  However according to the UHCI spec, Bit 7 of the port
429 	 * status and control register is always set to 1.  So we try to
430 	 * use this to our advantage.  Another common failure mode when
431 	 * a nonexistent register is addressed is to return all ones, so
432 	 * we test for that also.
433 	 */
434 	for (port = 0; port < (io_size - USBPORTSC1) / 2; port++) {
435 		unsigned int portstatus;
436 
437 		portstatus = inw(uhci->io_addr + USBPORTSC1 + (port * 2));
438 		if (!(portstatus & 0x0080) || portstatus == 0xffff)
439 			break;
440 	}
441 	if (debug)
442 		dev_info(uhci_dev(uhci), "detected %d ports\n", port);
443 
444 	/* Anything greater than 7 is weird so we'll ignore it. */
445 	if (port > UHCI_RH_MAXCHILD) {
446 		dev_info(uhci_dev(uhci), "port count misdetected? "
447 				"forcing to 2 ports\n");
448 		port = 2;
449 	}
450 	uhci->rh_numports = port;
451 
452 	/* Kick BIOS off this hardware and reset if the controller
453 	 * isn't already safely quiescent.
454 	 */
455 	check_and_reset_hc(uhci);
456 	return 0;
457 }
458 
459 /* Make sure the controller is quiescent and that we're not using it
460  * any more.  This is mainly for the benefit of programs which, like kexec,
461  * expect the hardware to be idle: not doing DMA or generating IRQs.
462  *
463  * This routine may be called in a damaged or failing kernel.  Hence we
464  * do not acquire the spinlock before shutting down the controller.
465  */
466 static void uhci_shutdown(struct pci_dev *pdev)
467 {
468 	struct usb_hcd *hcd = (struct usb_hcd *) pci_get_drvdata(pdev);
469 
470 	uhci_hc_died(hcd_to_uhci(hcd));
471 }
472 
473 /*
474  * Allocate a frame list, and then setup the skeleton
475  *
476  * The hardware doesn't really know any difference
477  * in the queues, but the order does matter for the
478  * protocols higher up. The order is:
479  *
480  *  - any isochronous events handled before any
481  *    of the queues. We don't do that here, because
482  *    we'll create the actual TD entries on demand.
483  *  - The first queue is the interrupt queue.
484  *  - The second queue is the control queue, split into low- and full-speed
485  *  - The third queue is bulk queue.
486  *  - The fourth queue is the bandwidth reclamation queue, which loops back
487  *    to the full-speed control queue.
488  */
489 static int uhci_start(struct usb_hcd *hcd)
490 {
491 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
492 	int retval = -EBUSY;
493 	int i;
494 	struct dentry *dentry;
495 
496 	hcd->uses_new_polling = 1;
497 
498 	spin_lock_init(&uhci->lock);
499 	setup_timer(&uhci->fsbr_timer, uhci_fsbr_timeout,
500 			(unsigned long) uhci);
501 	INIT_LIST_HEAD(&uhci->idle_qh_list);
502 	init_waitqueue_head(&uhci->waitqh);
503 
504 	if (DEBUG_CONFIGURED) {
505 		dentry = debugfs_create_file(hcd->self.bus_name,
506 				S_IFREG|S_IRUGO|S_IWUSR, uhci_debugfs_root,
507 				uhci, &uhci_debug_operations);
508 		if (!dentry) {
509 			dev_err(uhci_dev(uhci), "couldn't create uhci "
510 					"debugfs entry\n");
511 			retval = -ENOMEM;
512 			goto err_create_debug_entry;
513 		}
514 		uhci->dentry = dentry;
515 	}
516 
517 	uhci->frame = dma_alloc_coherent(uhci_dev(uhci),
518 			UHCI_NUMFRAMES * sizeof(*uhci->frame),
519 			&uhci->frame_dma_handle, 0);
520 	if (!uhci->frame) {
521 		dev_err(uhci_dev(uhci), "unable to allocate "
522 				"consistent memory for frame list\n");
523 		goto err_alloc_frame;
524 	}
525 	memset(uhci->frame, 0, UHCI_NUMFRAMES * sizeof(*uhci->frame));
526 
527 	uhci->frame_cpu = kcalloc(UHCI_NUMFRAMES, sizeof(*uhci->frame_cpu),
528 			GFP_KERNEL);
529 	if (!uhci->frame_cpu) {
530 		dev_err(uhci_dev(uhci), "unable to allocate "
531 				"memory for frame pointers\n");
532 		goto err_alloc_frame_cpu;
533 	}
534 
535 	uhci->td_pool = dma_pool_create("uhci_td", uhci_dev(uhci),
536 			sizeof(struct uhci_td), 16, 0);
537 	if (!uhci->td_pool) {
538 		dev_err(uhci_dev(uhci), "unable to create td dma_pool\n");
539 		goto err_create_td_pool;
540 	}
541 
542 	uhci->qh_pool = dma_pool_create("uhci_qh", uhci_dev(uhci),
543 			sizeof(struct uhci_qh), 16, 0);
544 	if (!uhci->qh_pool) {
545 		dev_err(uhci_dev(uhci), "unable to create qh dma_pool\n");
546 		goto err_create_qh_pool;
547 	}
548 
549 	uhci->term_td = uhci_alloc_td(uhci);
550 	if (!uhci->term_td) {
551 		dev_err(uhci_dev(uhci), "unable to allocate terminating TD\n");
552 		goto err_alloc_term_td;
553 	}
554 
555 	for (i = 0; i < UHCI_NUM_SKELQH; i++) {
556 		uhci->skelqh[i] = uhci_alloc_qh(uhci, NULL, NULL);
557 		if (!uhci->skelqh[i]) {
558 			dev_err(uhci_dev(uhci), "unable to allocate QH\n");
559 			goto err_alloc_skelqh;
560 		}
561 	}
562 
563 	/*
564 	 * 8 Interrupt queues; link all higher int queues to int1,
565 	 * then link int1 to control and control to bulk
566 	 */
567 	uhci->skel_int128_qh->link =
568 			uhci->skel_int64_qh->link =
569 			uhci->skel_int32_qh->link =
570 			uhci->skel_int16_qh->link =
571 			uhci->skel_int8_qh->link =
572 			uhci->skel_int4_qh->link =
573 			uhci->skel_int2_qh->link = UHCI_PTR_QH |
574 			cpu_to_le32(uhci->skel_int1_qh->dma_handle);
575 
576 	uhci->skel_int1_qh->link = UHCI_PTR_QH |
577 			cpu_to_le32(uhci->skel_ls_control_qh->dma_handle);
578 	uhci->skel_ls_control_qh->link = UHCI_PTR_QH |
579 			cpu_to_le32(uhci->skel_fs_control_qh->dma_handle);
580 	uhci->skel_fs_control_qh->link = UHCI_PTR_QH |
581 			cpu_to_le32(uhci->skel_bulk_qh->dma_handle);
582 	uhci->skel_bulk_qh->link = UHCI_PTR_QH |
583 			cpu_to_le32(uhci->skel_term_qh->dma_handle);
584 
585 	/* This dummy TD is to work around a bug in Intel PIIX controllers */
586 	uhci_fill_td(uhci->term_td, 0, uhci_explen(0) |
587 		(0x7f << TD_TOKEN_DEVADDR_SHIFT) | USB_PID_IN, 0);
588 	uhci->term_td->link = cpu_to_le32(uhci->term_td->dma_handle);
589 
590 	uhci->skel_term_qh->link = UHCI_PTR_TERM;
591 	uhci->skel_term_qh->element = cpu_to_le32(uhci->term_td->dma_handle);
592 
593 	/*
594 	 * Fill the frame list: make all entries point to the proper
595 	 * interrupt queue.
596 	 *
597 	 * The interrupt queues will be interleaved as evenly as possible.
598 	 * There's not much to be done about period-1 interrupts; they have
599 	 * to occur in every frame.  But we can schedule period-2 interrupts
600 	 * in odd-numbered frames, period-4 interrupts in frames congruent
601 	 * to 2 (mod 4), and so on.  This way each frame only has two
602 	 * interrupt QHs, which will help spread out bandwidth utilization.
603 	 */
604 	for (i = 0; i < UHCI_NUMFRAMES; i++) {
605 		int irq;
606 
607 		/*
608 		 * ffs (Find First bit Set) does exactly what we need:
609 		 * 1,3,5,...  => ffs = 0 => use skel_int2_qh = skelqh[8],
610 		 * 2,6,10,... => ffs = 1 => use skel_int4_qh = skelqh[7], etc.
611 		 * ffs >= 7 => not on any high-period queue, so use
612 		 *	skel_int1_qh = skelqh[9].
613 		 * Add UHCI_NUMFRAMES to insure at least one bit is set.
614 		 */
615 		irq = 8 - (int) __ffs(i + UHCI_NUMFRAMES);
616 		if (irq <= 1)
617 			irq = 9;
618 
619 		/* Only place we don't use the frame list routines */
620 		uhci->frame[i] = UHCI_PTR_QH |
621 				cpu_to_le32(uhci->skelqh[irq]->dma_handle);
622 	}
623 
624 	/*
625 	 * Some architectures require a full mb() to enforce completion of
626 	 * the memory writes above before the I/O transfers in configure_hc().
627 	 */
628 	mb();
629 
630 	configure_hc(uhci);
631 	uhci->is_initialized = 1;
632 	start_rh(uhci);
633 	return 0;
634 
635 /*
636  * error exits:
637  */
638 err_alloc_skelqh:
639 	for (i = 0; i < UHCI_NUM_SKELQH; i++) {
640 		if (uhci->skelqh[i])
641 			uhci_free_qh(uhci, uhci->skelqh[i]);
642 	}
643 
644 	uhci_free_td(uhci, uhci->term_td);
645 
646 err_alloc_term_td:
647 	dma_pool_destroy(uhci->qh_pool);
648 
649 err_create_qh_pool:
650 	dma_pool_destroy(uhci->td_pool);
651 
652 err_create_td_pool:
653 	kfree(uhci->frame_cpu);
654 
655 err_alloc_frame_cpu:
656 	dma_free_coherent(uhci_dev(uhci),
657 			UHCI_NUMFRAMES * sizeof(*uhci->frame),
658 			uhci->frame, uhci->frame_dma_handle);
659 
660 err_alloc_frame:
661 	debugfs_remove(uhci->dentry);
662 
663 err_create_debug_entry:
664 	return retval;
665 }
666 
667 static void uhci_stop(struct usb_hcd *hcd)
668 {
669 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
670 
671 	spin_lock_irq(&uhci->lock);
672 	if (test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) && !uhci->dead)
673 		uhci_hc_died(uhci);
674 	uhci_scan_schedule(uhci, NULL);
675 	spin_unlock_irq(&uhci->lock);
676 
677 	del_timer_sync(&uhci->fsbr_timer);
678 	release_uhci(uhci);
679 }
680 
681 #ifdef CONFIG_PM
682 static int uhci_rh_suspend(struct usb_hcd *hcd)
683 {
684 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
685 	int rc = 0;
686 
687 	spin_lock_irq(&uhci->lock);
688 	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))
689 		rc = -ESHUTDOWN;
690 	else if (!uhci->dead)
691 		suspend_rh(uhci, UHCI_RH_SUSPENDED);
692 	spin_unlock_irq(&uhci->lock);
693 	return rc;
694 }
695 
696 static int uhci_rh_resume(struct usb_hcd *hcd)
697 {
698 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
699 	int rc = 0;
700 
701 	spin_lock_irq(&uhci->lock);
702 	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
703 		dev_warn(&hcd->self.root_hub->dev, "HC isn't running!\n");
704 		rc = -ESHUTDOWN;
705 	} else if (!uhci->dead)
706 		wakeup_rh(uhci);
707 	spin_unlock_irq(&uhci->lock);
708 	return rc;
709 }
710 
711 static int uhci_suspend(struct usb_hcd *hcd, pm_message_t message)
712 {
713 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
714 	int rc = 0;
715 
716 	dev_dbg(uhci_dev(uhci), "%s\n", __FUNCTION__);
717 
718 	spin_lock_irq(&uhci->lock);
719 	if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) || uhci->dead)
720 		goto done_okay;		/* Already suspended or dead */
721 
722 	if (uhci->rh_state > UHCI_RH_SUSPENDED) {
723 		dev_warn(uhci_dev(uhci), "Root hub isn't suspended!\n");
724 		rc = -EBUSY;
725 		goto done;
726 	};
727 
728 	/* All PCI host controllers are required to disable IRQ generation
729 	 * at the source, so we must turn off PIRQ.
730 	 */
731 	pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP, 0);
732 	mb();
733 	hcd->poll_rh = 0;
734 
735 	/* FIXME: Enable non-PME# remote wakeup? */
736 
737 done_okay:
738 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
739 done:
740 	spin_unlock_irq(&uhci->lock);
741 	return rc;
742 }
743 
744 static int uhci_resume(struct usb_hcd *hcd)
745 {
746 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
747 
748 	dev_dbg(uhci_dev(uhci), "%s\n", __FUNCTION__);
749 
750 	/* Since we aren't in D3 any more, it's safe to set this flag
751 	 * even if the controller was dead.
752 	 */
753 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
754 	mb();
755 
756 	spin_lock_irq(&uhci->lock);
757 
758 	/* FIXME: Disable non-PME# remote wakeup? */
759 
760 	/* The firmware or a boot kernel may have changed the controller
761 	 * settings during a system wakeup.  Check it and reconfigure
762 	 * to avoid problems.
763 	 */
764 	check_and_reset_hc(uhci);
765 
766 	/* If the controller was dead before, it's back alive now */
767 	configure_hc(uhci);
768 
769 	if (uhci->rh_state == UHCI_RH_RESET) {
770 
771 		/* The controller had to be reset */
772 		usb_root_hub_lost_power(hcd->self.root_hub);
773 		suspend_rh(uhci, UHCI_RH_SUSPENDED);
774 	}
775 
776 	spin_unlock_irq(&uhci->lock);
777 
778 	if (!uhci->working_RD) {
779 		/* Suspended root hub needs to be polled */
780 		hcd->poll_rh = 1;
781 		usb_hcd_poll_rh_status(hcd);
782 	}
783 	return 0;
784 }
785 #endif
786 
787 /* Wait until a particular device/endpoint's QH is idle, and free it */
788 static void uhci_hcd_endpoint_disable(struct usb_hcd *hcd,
789 		struct usb_host_endpoint *hep)
790 {
791 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
792 	struct uhci_qh *qh;
793 
794 	spin_lock_irq(&uhci->lock);
795 	qh = (struct uhci_qh *) hep->hcpriv;
796 	if (qh == NULL)
797 		goto done;
798 
799 	while (qh->state != QH_STATE_IDLE) {
800 		++uhci->num_waiting;
801 		spin_unlock_irq(&uhci->lock);
802 		wait_event_interruptible(uhci->waitqh,
803 				qh->state == QH_STATE_IDLE);
804 		spin_lock_irq(&uhci->lock);
805 		--uhci->num_waiting;
806 	}
807 
808 	uhci_free_qh(uhci, qh);
809 done:
810 	spin_unlock_irq(&uhci->lock);
811 }
812 
813 static int uhci_hcd_get_frame_number(struct usb_hcd *hcd)
814 {
815 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
816 	unsigned frame_number;
817 	unsigned delta;
818 
819 	/* Minimize latency by avoiding the spinlock */
820 	frame_number = uhci->frame_number;
821 	barrier();
822 	delta = (inw(uhci->io_addr + USBFRNUM) - frame_number) &
823 			(UHCI_NUMFRAMES - 1);
824 	return frame_number + delta;
825 }
826 
827 static const char hcd_name[] = "uhci_hcd";
828 
829 static const struct hc_driver uhci_driver = {
830 	.description =		hcd_name,
831 	.product_desc =		"UHCI Host Controller",
832 	.hcd_priv_size =	sizeof(struct uhci_hcd),
833 
834 	/* Generic hardware linkage */
835 	.irq =			uhci_irq,
836 	.flags =		HCD_USB11,
837 
838 	/* Basic lifecycle operations */
839 	.reset =		uhci_init,
840 	.start =		uhci_start,
841 #ifdef CONFIG_PM
842 	.suspend =		uhci_suspend,
843 	.resume =		uhci_resume,
844 	.bus_suspend =		uhci_rh_suspend,
845 	.bus_resume =		uhci_rh_resume,
846 #endif
847 	.stop =			uhci_stop,
848 
849 	.urb_enqueue =		uhci_urb_enqueue,
850 	.urb_dequeue =		uhci_urb_dequeue,
851 
852 	.endpoint_disable =	uhci_hcd_endpoint_disable,
853 	.get_frame_number =	uhci_hcd_get_frame_number,
854 
855 	.hub_status_data =	uhci_hub_status_data,
856 	.hub_control =		uhci_hub_control,
857 };
858 
859 static const struct pci_device_id uhci_pci_ids[] = { {
860 	/* handle any USB UHCI controller */
861 	PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_UHCI, ~0),
862 	.driver_data =	(unsigned long) &uhci_driver,
863 	}, { /* end: all zeroes */ }
864 };
865 
866 MODULE_DEVICE_TABLE(pci, uhci_pci_ids);
867 
868 static struct pci_driver uhci_pci_driver = {
869 	.name =		(char *)hcd_name,
870 	.id_table =	uhci_pci_ids,
871 
872 	.probe =	usb_hcd_pci_probe,
873 	.remove =	usb_hcd_pci_remove,
874 	.shutdown =	uhci_shutdown,
875 
876 #ifdef	CONFIG_PM
877 	.suspend =	usb_hcd_pci_suspend,
878 	.resume =	usb_hcd_pci_resume,
879 #endif	/* PM */
880 };
881 
882 static int __init uhci_hcd_init(void)
883 {
884 	int retval = -ENOMEM;
885 
886 	printk(KERN_INFO DRIVER_DESC " " DRIVER_VERSION "\n");
887 
888 	if (usb_disabled())
889 		return -ENODEV;
890 
891 	if (DEBUG_CONFIGURED) {
892 		errbuf = kmalloc(ERRBUF_LEN, GFP_KERNEL);
893 		if (!errbuf)
894 			goto errbuf_failed;
895 		uhci_debugfs_root = debugfs_create_dir("uhci", NULL);
896 		if (!uhci_debugfs_root)
897 			goto debug_failed;
898 	}
899 
900 	uhci_up_cachep = kmem_cache_create("uhci_urb_priv",
901 		sizeof(struct urb_priv), 0, 0, NULL, NULL);
902 	if (!uhci_up_cachep)
903 		goto up_failed;
904 
905 	retval = pci_register_driver(&uhci_pci_driver);
906 	if (retval)
907 		goto init_failed;
908 
909 	return 0;
910 
911 init_failed:
912 	if (kmem_cache_destroy(uhci_up_cachep))
913 		warn("not all urb_privs were freed!");
914 
915 up_failed:
916 	debugfs_remove(uhci_debugfs_root);
917 
918 debug_failed:
919 	kfree(errbuf);
920 
921 errbuf_failed:
922 
923 	return retval;
924 }
925 
926 static void __exit uhci_hcd_cleanup(void)
927 {
928 	pci_unregister_driver(&uhci_pci_driver);
929 
930 	if (kmem_cache_destroy(uhci_up_cachep))
931 		warn("not all urb_privs were freed!");
932 
933 	debugfs_remove(uhci_debugfs_root);
934 	kfree(errbuf);
935 }
936 
937 module_init(uhci_hcd_init);
938 module_exit(uhci_hcd_cleanup);
939 
940 MODULE_AUTHOR(DRIVER_AUTHOR);
941 MODULE_DESCRIPTION(DRIVER_DESC);
942 MODULE_LICENSE("GPL");
943