xref: /linux/drivers/usb/core/hcd.c (revision b58b13f156c00c2457035b7071eaaac105fe6836)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright Linus Torvalds 1999
4  * (C) Copyright Johannes Erdfelt 1999-2001
5  * (C) Copyright Andreas Gal 1999
6  * (C) Copyright Gregory P. Smith 1999
7  * (C) Copyright Deti Fliegl 1999
8  * (C) Copyright Randy Dunlap 2000
9  * (C) Copyright David Brownell 2000-2002
10  */
11 
12 #include <linux/bcd.h>
13 #include <linux/module.h>
14 #include <linux/version.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/slab.h>
18 #include <linux/completion.h>
19 #include <linux/utsname.h>
20 #include <linux/mm.h>
21 #include <asm/io.h>
22 #include <linux/device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/mutex.h>
25 #include <asm/irq.h>
26 #include <asm/byteorder.h>
27 #include <asm/unaligned.h>
28 #include <linux/platform_device.h>
29 #include <linux/workqueue.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/types.h>
32 #include <linux/genalloc.h>
33 #include <linux/io.h>
34 #include <linux/kcov.h>
35 
36 #include <linux/phy/phy.h>
37 #include <linux/usb.h>
38 #include <linux/usb/hcd.h>
39 #include <linux/usb/otg.h>
40 
41 #include "usb.h"
42 #include "phy.h"
43 
44 
45 /*-------------------------------------------------------------------------*/
46 
47 /*
48  * USB Host Controller Driver framework
49  *
50  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
51  * HCD-specific behaviors/bugs.
52  *
53  * This does error checks, tracks devices and urbs, and delegates to a
54  * "hc_driver" only for code (and data) that really needs to know about
55  * hardware differences.  That includes root hub registers, i/o queues,
56  * and so on ... but as little else as possible.
57  *
58  * Shared code includes most of the "root hub" code (these are emulated,
59  * though each HC's hardware works differently) and PCI glue, plus request
60  * tracking overhead.  The HCD code should only block on spinlocks or on
61  * hardware handshaking; blocking on software events (such as other kernel
62  * threads releasing resources, or completing actions) is all generic.
63  *
64  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
65  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
66  * only by the hub driver ... and that neither should be seen or used by
67  * usb client device drivers.
68  *
69  * Contributors of ideas or unattributed patches include: David Brownell,
70  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
71  *
72  * HISTORY:
73  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
74  *		associated cleanup.  "usb_hcd" still != "usb_bus".
75  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
76  */
77 
78 /*-------------------------------------------------------------------------*/
79 
80 /* Keep track of which host controller drivers are loaded */
81 unsigned long usb_hcds_loaded;
82 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
83 
84 /* host controllers we manage */
85 DEFINE_IDR (usb_bus_idr);
86 EXPORT_SYMBOL_GPL (usb_bus_idr);
87 
88 /* used when allocating bus numbers */
89 #define USB_MAXBUS		64
90 
91 /* used when updating list of hcds */
92 DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
93 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
94 
95 /* used for controlling access to virtual root hubs */
96 static DEFINE_SPINLOCK(hcd_root_hub_lock);
97 
98 /* used when updating an endpoint's URB list */
99 static DEFINE_SPINLOCK(hcd_urb_list_lock);
100 
101 /* used to protect against unlinking URBs after the device is gone */
102 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
103 
104 /* wait queue for synchronous unlinks */
105 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
106 
107 /*-------------------------------------------------------------------------*/
108 
109 /*
110  * Sharable chunks of root hub code.
111  */
112 
113 /*-------------------------------------------------------------------------*/
114 #define KERNEL_REL	bin2bcd(LINUX_VERSION_MAJOR)
115 #define KERNEL_VER	bin2bcd(LINUX_VERSION_PATCHLEVEL)
116 
117 /* usb 3.1 root hub device descriptor */
118 static const u8 usb31_rh_dev_descriptor[18] = {
119 	0x12,       /*  __u8  bLength; */
120 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
121 	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
122 
123 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
124 	0x00,	    /*  __u8  bDeviceSubClass; */
125 	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
126 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
127 
128 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
129 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
130 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
131 
132 	0x03,       /*  __u8  iManufacturer; */
133 	0x02,       /*  __u8  iProduct; */
134 	0x01,       /*  __u8  iSerialNumber; */
135 	0x01        /*  __u8  bNumConfigurations; */
136 };
137 
138 /* usb 3.0 root hub device descriptor */
139 static const u8 usb3_rh_dev_descriptor[18] = {
140 	0x12,       /*  __u8  bLength; */
141 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
142 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
143 
144 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
145 	0x00,	    /*  __u8  bDeviceSubClass; */
146 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
147 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
148 
149 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
150 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
151 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
152 
153 	0x03,       /*  __u8  iManufacturer; */
154 	0x02,       /*  __u8  iProduct; */
155 	0x01,       /*  __u8  iSerialNumber; */
156 	0x01        /*  __u8  bNumConfigurations; */
157 };
158 
159 /* usb 2.0 root hub device descriptor */
160 static const u8 usb2_rh_dev_descriptor[18] = {
161 	0x12,       /*  __u8  bLength; */
162 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
163 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
164 
165 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
166 	0x00,	    /*  __u8  bDeviceSubClass; */
167 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
168 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
169 
170 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
171 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
172 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
173 
174 	0x03,       /*  __u8  iManufacturer; */
175 	0x02,       /*  __u8  iProduct; */
176 	0x01,       /*  __u8  iSerialNumber; */
177 	0x01        /*  __u8  bNumConfigurations; */
178 };
179 
180 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
181 
182 /* usb 1.1 root hub device descriptor */
183 static const u8 usb11_rh_dev_descriptor[18] = {
184 	0x12,       /*  __u8  bLength; */
185 	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
186 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
187 
188 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
189 	0x00,	    /*  __u8  bDeviceSubClass; */
190 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
191 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
192 
193 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
194 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
195 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
196 
197 	0x03,       /*  __u8  iManufacturer; */
198 	0x02,       /*  __u8  iProduct; */
199 	0x01,       /*  __u8  iSerialNumber; */
200 	0x01        /*  __u8  bNumConfigurations; */
201 };
202 
203 
204 /*-------------------------------------------------------------------------*/
205 
206 /* Configuration descriptors for our root hubs */
207 
208 static const u8 fs_rh_config_descriptor[] = {
209 
210 	/* one configuration */
211 	0x09,       /*  __u8  bLength; */
212 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
213 	0x19, 0x00, /*  __le16 wTotalLength; */
214 	0x01,       /*  __u8  bNumInterfaces; (1) */
215 	0x01,       /*  __u8  bConfigurationValue; */
216 	0x00,       /*  __u8  iConfiguration; */
217 	0xc0,       /*  __u8  bmAttributes;
218 				 Bit 7: must be set,
219 				     6: Self-powered,
220 				     5: Remote wakeup,
221 				     4..0: resvd */
222 	0x00,       /*  __u8  MaxPower; */
223 
224 	/* USB 1.1:
225 	 * USB 2.0, single TT organization (mandatory):
226 	 *	one interface, protocol 0
227 	 *
228 	 * USB 2.0, multiple TT organization (optional):
229 	 *	two interfaces, protocols 1 (like single TT)
230 	 *	and 2 (multiple TT mode) ... config is
231 	 *	sometimes settable
232 	 *	NOT IMPLEMENTED
233 	 */
234 
235 	/* one interface */
236 	0x09,       /*  __u8  if_bLength; */
237 	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
238 	0x00,       /*  __u8  if_bInterfaceNumber; */
239 	0x00,       /*  __u8  if_bAlternateSetting; */
240 	0x01,       /*  __u8  if_bNumEndpoints; */
241 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
242 	0x00,       /*  __u8  if_bInterfaceSubClass; */
243 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
244 	0x00,       /*  __u8  if_iInterface; */
245 
246 	/* one endpoint (status change endpoint) */
247 	0x07,       /*  __u8  ep_bLength; */
248 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
249 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
250 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
251 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
252 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
253 };
254 
255 static const u8 hs_rh_config_descriptor[] = {
256 
257 	/* one configuration */
258 	0x09,       /*  __u8  bLength; */
259 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
260 	0x19, 0x00, /*  __le16 wTotalLength; */
261 	0x01,       /*  __u8  bNumInterfaces; (1) */
262 	0x01,       /*  __u8  bConfigurationValue; */
263 	0x00,       /*  __u8  iConfiguration; */
264 	0xc0,       /*  __u8  bmAttributes;
265 				 Bit 7: must be set,
266 				     6: Self-powered,
267 				     5: Remote wakeup,
268 				     4..0: resvd */
269 	0x00,       /*  __u8  MaxPower; */
270 
271 	/* USB 1.1:
272 	 * USB 2.0, single TT organization (mandatory):
273 	 *	one interface, protocol 0
274 	 *
275 	 * USB 2.0, multiple TT organization (optional):
276 	 *	two interfaces, protocols 1 (like single TT)
277 	 *	and 2 (multiple TT mode) ... config is
278 	 *	sometimes settable
279 	 *	NOT IMPLEMENTED
280 	 */
281 
282 	/* one interface */
283 	0x09,       /*  __u8  if_bLength; */
284 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
285 	0x00,       /*  __u8  if_bInterfaceNumber; */
286 	0x00,       /*  __u8  if_bAlternateSetting; */
287 	0x01,       /*  __u8  if_bNumEndpoints; */
288 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
289 	0x00,       /*  __u8  if_bInterfaceSubClass; */
290 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
291 	0x00,       /*  __u8  if_iInterface; */
292 
293 	/* one endpoint (status change endpoint) */
294 	0x07,       /*  __u8  ep_bLength; */
295 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
296 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
297 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
298 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
299 		     * see hub.c:hub_configure() for details. */
300 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
301 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
302 };
303 
304 static const u8 ss_rh_config_descriptor[] = {
305 	/* one configuration */
306 	0x09,       /*  __u8  bLength; */
307 	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
308 	0x1f, 0x00, /*  __le16 wTotalLength; */
309 	0x01,       /*  __u8  bNumInterfaces; (1) */
310 	0x01,       /*  __u8  bConfigurationValue; */
311 	0x00,       /*  __u8  iConfiguration; */
312 	0xc0,       /*  __u8  bmAttributes;
313 				 Bit 7: must be set,
314 				     6: Self-powered,
315 				     5: Remote wakeup,
316 				     4..0: resvd */
317 	0x00,       /*  __u8  MaxPower; */
318 
319 	/* one interface */
320 	0x09,       /*  __u8  if_bLength; */
321 	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
322 	0x00,       /*  __u8  if_bInterfaceNumber; */
323 	0x00,       /*  __u8  if_bAlternateSetting; */
324 	0x01,       /*  __u8  if_bNumEndpoints; */
325 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
326 	0x00,       /*  __u8  if_bInterfaceSubClass; */
327 	0x00,       /*  __u8  if_bInterfaceProtocol; */
328 	0x00,       /*  __u8  if_iInterface; */
329 
330 	/* one endpoint (status change endpoint) */
331 	0x07,       /*  __u8  ep_bLength; */
332 	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
333 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
334 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
335 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
336 		     * see hub.c:hub_configure() for details. */
337 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
338 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
339 
340 	/* one SuperSpeed endpoint companion descriptor */
341 	0x06,        /* __u8 ss_bLength */
342 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
343 		     /* Companion */
344 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
345 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
346 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
347 };
348 
349 /* authorized_default behaviour:
350  * -1 is authorized for all devices (leftover from wireless USB)
351  * 0 is unauthorized for all devices
352  * 1 is authorized for all devices
353  * 2 is authorized for internal devices
354  */
355 #define USB_AUTHORIZE_WIRED	-1
356 #define USB_AUTHORIZE_NONE	0
357 #define USB_AUTHORIZE_ALL	1
358 #define USB_AUTHORIZE_INTERNAL	2
359 
360 static int authorized_default = USB_AUTHORIZE_WIRED;
361 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
362 MODULE_PARM_DESC(authorized_default,
363 		"Default USB device authorization: 0 is not authorized, 1 is "
364 		"authorized, 2 is authorized for internal devices, -1 is "
365 		"authorized (default, same as 1)");
366 /*-------------------------------------------------------------------------*/
367 
368 /**
369  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
370  * @s: Null-terminated ASCII (actually ISO-8859-1) string
371  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
372  * @len: Length (in bytes; may be odd) of descriptor buffer.
373  *
374  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
375  * whichever is less.
376  *
377  * Note:
378  * USB String descriptors can contain at most 126 characters; input
379  * strings longer than that are truncated.
380  */
381 static unsigned
382 ascii2desc(char const *s, u8 *buf, unsigned len)
383 {
384 	unsigned n, t = 2 + 2*strlen(s);
385 
386 	if (t > 254)
387 		t = 254;	/* Longest possible UTF string descriptor */
388 	if (len > t)
389 		len = t;
390 
391 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
392 
393 	n = len;
394 	while (n--) {
395 		*buf++ = t;
396 		if (!n--)
397 			break;
398 		*buf++ = t >> 8;
399 		t = (unsigned char)*s++;
400 	}
401 	return len;
402 }
403 
404 /**
405  * rh_string() - provides string descriptors for root hub
406  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
407  * @hcd: the host controller for this root hub
408  * @data: buffer for output packet
409  * @len: length of the provided buffer
410  *
411  * Produces either a manufacturer, product or serial number string for the
412  * virtual root hub device.
413  *
414  * Return: The number of bytes filled in: the length of the descriptor or
415  * of the provided buffer, whichever is less.
416  */
417 static unsigned
418 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
419 {
420 	char buf[100];
421 	char const *s;
422 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
423 
424 	/* language ids */
425 	switch (id) {
426 	case 0:
427 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
428 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
429 		if (len > 4)
430 			len = 4;
431 		memcpy(data, langids, len);
432 		return len;
433 	case 1:
434 		/* Serial number */
435 		s = hcd->self.bus_name;
436 		break;
437 	case 2:
438 		/* Product name */
439 		s = hcd->product_desc;
440 		break;
441 	case 3:
442 		/* Manufacturer */
443 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
444 			init_utsname()->release, hcd->driver->description);
445 		s = buf;
446 		break;
447 	default:
448 		/* Can't happen; caller guarantees it */
449 		return 0;
450 	}
451 
452 	return ascii2desc(s, data, len);
453 }
454 
455 
456 /* Root hub control transfers execute synchronously */
457 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
458 {
459 	struct usb_ctrlrequest *cmd;
460 	u16		typeReq, wValue, wIndex, wLength;
461 	u8		*ubuf = urb->transfer_buffer;
462 	unsigned	len = 0;
463 	int		status;
464 	u8		patch_wakeup = 0;
465 	u8		patch_protocol = 0;
466 	u16		tbuf_size;
467 	u8		*tbuf = NULL;
468 	const u8	*bufp;
469 
470 	might_sleep();
471 
472 	spin_lock_irq(&hcd_root_hub_lock);
473 	status = usb_hcd_link_urb_to_ep(hcd, urb);
474 	spin_unlock_irq(&hcd_root_hub_lock);
475 	if (status)
476 		return status;
477 	urb->hcpriv = hcd;	/* Indicate it's queued */
478 
479 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
480 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
481 	wValue   = le16_to_cpu (cmd->wValue);
482 	wIndex   = le16_to_cpu (cmd->wIndex);
483 	wLength  = le16_to_cpu (cmd->wLength);
484 
485 	if (wLength > urb->transfer_buffer_length)
486 		goto error;
487 
488 	/*
489 	 * tbuf should be at least as big as the
490 	 * USB hub descriptor.
491 	 */
492 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
493 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
494 	if (!tbuf) {
495 		status = -ENOMEM;
496 		goto err_alloc;
497 	}
498 
499 	bufp = tbuf;
500 
501 
502 	urb->actual_length = 0;
503 	switch (typeReq) {
504 
505 	/* DEVICE REQUESTS */
506 
507 	/* The root hub's remote wakeup enable bit is implemented using
508 	 * driver model wakeup flags.  If this system supports wakeup
509 	 * through USB, userspace may change the default "allow wakeup"
510 	 * policy through sysfs or these calls.
511 	 *
512 	 * Most root hubs support wakeup from downstream devices, for
513 	 * runtime power management (disabling USB clocks and reducing
514 	 * VBUS power usage).  However, not all of them do so; silicon,
515 	 * board, and BIOS bugs here are not uncommon, so these can't
516 	 * be treated quite like external hubs.
517 	 *
518 	 * Likewise, not all root hubs will pass wakeup events upstream,
519 	 * to wake up the whole system.  So don't assume root hub and
520 	 * controller capabilities are identical.
521 	 */
522 
523 	case DeviceRequest | USB_REQ_GET_STATUS:
524 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
525 					<< USB_DEVICE_REMOTE_WAKEUP)
526 				| (1 << USB_DEVICE_SELF_POWERED);
527 		tbuf[1] = 0;
528 		len = 2;
529 		break;
530 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
531 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
532 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
533 		else
534 			goto error;
535 		break;
536 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
537 		if (device_can_wakeup(&hcd->self.root_hub->dev)
538 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
539 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
540 		else
541 			goto error;
542 		break;
543 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
544 		tbuf[0] = 1;
545 		len = 1;
546 		fallthrough;
547 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
548 		break;
549 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
550 		switch (wValue & 0xff00) {
551 		case USB_DT_DEVICE << 8:
552 			switch (hcd->speed) {
553 			case HCD_USB32:
554 			case HCD_USB31:
555 				bufp = usb31_rh_dev_descriptor;
556 				break;
557 			case HCD_USB3:
558 				bufp = usb3_rh_dev_descriptor;
559 				break;
560 			case HCD_USB2:
561 				bufp = usb2_rh_dev_descriptor;
562 				break;
563 			case HCD_USB11:
564 				bufp = usb11_rh_dev_descriptor;
565 				break;
566 			default:
567 				goto error;
568 			}
569 			len = 18;
570 			if (hcd->has_tt)
571 				patch_protocol = 1;
572 			break;
573 		case USB_DT_CONFIG << 8:
574 			switch (hcd->speed) {
575 			case HCD_USB32:
576 			case HCD_USB31:
577 			case HCD_USB3:
578 				bufp = ss_rh_config_descriptor;
579 				len = sizeof ss_rh_config_descriptor;
580 				break;
581 			case HCD_USB2:
582 				bufp = hs_rh_config_descriptor;
583 				len = sizeof hs_rh_config_descriptor;
584 				break;
585 			case HCD_USB11:
586 				bufp = fs_rh_config_descriptor;
587 				len = sizeof fs_rh_config_descriptor;
588 				break;
589 			default:
590 				goto error;
591 			}
592 			if (device_can_wakeup(&hcd->self.root_hub->dev))
593 				patch_wakeup = 1;
594 			break;
595 		case USB_DT_STRING << 8:
596 			if ((wValue & 0xff) < 4)
597 				urb->actual_length = rh_string(wValue & 0xff,
598 						hcd, ubuf, wLength);
599 			else /* unsupported IDs --> "protocol stall" */
600 				goto error;
601 			break;
602 		case USB_DT_BOS << 8:
603 			goto nongeneric;
604 		default:
605 			goto error;
606 		}
607 		break;
608 	case DeviceRequest | USB_REQ_GET_INTERFACE:
609 		tbuf[0] = 0;
610 		len = 1;
611 		fallthrough;
612 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
613 		break;
614 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
615 		/* wValue == urb->dev->devaddr */
616 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
617 			wValue);
618 		break;
619 
620 	/* INTERFACE REQUESTS (no defined feature/status flags) */
621 
622 	/* ENDPOINT REQUESTS */
623 
624 	case EndpointRequest | USB_REQ_GET_STATUS:
625 		/* ENDPOINT_HALT flag */
626 		tbuf[0] = 0;
627 		tbuf[1] = 0;
628 		len = 2;
629 		fallthrough;
630 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
631 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
632 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
633 		break;
634 
635 	/* CLASS REQUESTS (and errors) */
636 
637 	default:
638 nongeneric:
639 		/* non-generic request */
640 		switch (typeReq) {
641 		case GetHubStatus:
642 			len = 4;
643 			break;
644 		case GetPortStatus:
645 			if (wValue == HUB_PORT_STATUS)
646 				len = 4;
647 			else
648 				/* other port status types return 8 bytes */
649 				len = 8;
650 			break;
651 		case GetHubDescriptor:
652 			len = sizeof (struct usb_hub_descriptor);
653 			break;
654 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
655 			/* len is returned by hub_control */
656 			break;
657 		}
658 		status = hcd->driver->hub_control (hcd,
659 			typeReq, wValue, wIndex,
660 			tbuf, wLength);
661 
662 		if (typeReq == GetHubDescriptor)
663 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
664 				(struct usb_hub_descriptor *)tbuf);
665 		break;
666 error:
667 		/* "protocol stall" on error */
668 		status = -EPIPE;
669 	}
670 
671 	if (status < 0) {
672 		len = 0;
673 		if (status != -EPIPE) {
674 			dev_dbg (hcd->self.controller,
675 				"CTRL: TypeReq=0x%x val=0x%x "
676 				"idx=0x%x len=%d ==> %d\n",
677 				typeReq, wValue, wIndex,
678 				wLength, status);
679 		}
680 	} else if (status > 0) {
681 		/* hub_control may return the length of data copied. */
682 		len = status;
683 		status = 0;
684 	}
685 	if (len) {
686 		if (urb->transfer_buffer_length < len)
687 			len = urb->transfer_buffer_length;
688 		urb->actual_length = len;
689 		/* always USB_DIR_IN, toward host */
690 		memcpy (ubuf, bufp, len);
691 
692 		/* report whether RH hardware supports remote wakeup */
693 		if (patch_wakeup &&
694 				len > offsetof (struct usb_config_descriptor,
695 						bmAttributes))
696 			((struct usb_config_descriptor *)ubuf)->bmAttributes
697 				|= USB_CONFIG_ATT_WAKEUP;
698 
699 		/* report whether RH hardware has an integrated TT */
700 		if (patch_protocol &&
701 				len > offsetof(struct usb_device_descriptor,
702 						bDeviceProtocol))
703 			((struct usb_device_descriptor *) ubuf)->
704 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
705 	}
706 
707 	kfree(tbuf);
708  err_alloc:
709 
710 	/* any errors get returned through the urb completion */
711 	spin_lock_irq(&hcd_root_hub_lock);
712 	usb_hcd_unlink_urb_from_ep(hcd, urb);
713 	usb_hcd_giveback_urb(hcd, urb, status);
714 	spin_unlock_irq(&hcd_root_hub_lock);
715 	return 0;
716 }
717 
718 /*-------------------------------------------------------------------------*/
719 
720 /*
721  * Root Hub interrupt transfers are polled using a timer if the
722  * driver requests it; otherwise the driver is responsible for
723  * calling usb_hcd_poll_rh_status() when an event occurs.
724  *
725  * Completion handler may not sleep. See usb_hcd_giveback_urb() for details.
726  */
727 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
728 {
729 	struct urb	*urb;
730 	int		length;
731 	int		status;
732 	unsigned long	flags;
733 	char		buffer[6];	/* Any root hubs with > 31 ports? */
734 
735 	if (unlikely(!hcd->rh_pollable))
736 		return;
737 	if (!hcd->uses_new_polling && !hcd->status_urb)
738 		return;
739 
740 	length = hcd->driver->hub_status_data(hcd, buffer);
741 	if (length > 0) {
742 
743 		/* try to complete the status urb */
744 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
745 		urb = hcd->status_urb;
746 		if (urb) {
747 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
748 			hcd->status_urb = NULL;
749 			if (urb->transfer_buffer_length >= length) {
750 				status = 0;
751 			} else {
752 				status = -EOVERFLOW;
753 				length = urb->transfer_buffer_length;
754 			}
755 			urb->actual_length = length;
756 			memcpy(urb->transfer_buffer, buffer, length);
757 
758 			usb_hcd_unlink_urb_from_ep(hcd, urb);
759 			usb_hcd_giveback_urb(hcd, urb, status);
760 		} else {
761 			length = 0;
762 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
763 		}
764 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
765 	}
766 
767 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
768 	 * exceed that limit if HZ is 100. The math is more clunky than
769 	 * maybe expected, this is to make sure that all timers for USB devices
770 	 * fire at the same time to give the CPU a break in between */
771 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
772 			(length == 0 && hcd->status_urb != NULL))
773 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
774 }
775 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
776 
777 /* timer callback */
778 static void rh_timer_func (struct timer_list *t)
779 {
780 	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
781 
782 	usb_hcd_poll_rh_status(_hcd);
783 }
784 
785 /*-------------------------------------------------------------------------*/
786 
787 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
788 {
789 	int		retval;
790 	unsigned long	flags;
791 	unsigned	len = 1 + (urb->dev->maxchild / 8);
792 
793 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
794 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
795 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
796 		retval = -EINVAL;
797 		goto done;
798 	}
799 
800 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
801 	if (retval)
802 		goto done;
803 
804 	hcd->status_urb = urb;
805 	urb->hcpriv = hcd;	/* indicate it's queued */
806 	if (!hcd->uses_new_polling)
807 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
808 
809 	/* If a status change has already occurred, report it ASAP */
810 	else if (HCD_POLL_PENDING(hcd))
811 		mod_timer(&hcd->rh_timer, jiffies);
812 	retval = 0;
813  done:
814 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
815 	return retval;
816 }
817 
818 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
819 {
820 	if (usb_endpoint_xfer_int(&urb->ep->desc))
821 		return rh_queue_status (hcd, urb);
822 	if (usb_endpoint_xfer_control(&urb->ep->desc))
823 		return rh_call_control (hcd, urb);
824 	return -EINVAL;
825 }
826 
827 /*-------------------------------------------------------------------------*/
828 
829 /* Unlinks of root-hub control URBs are legal, but they don't do anything
830  * since these URBs always execute synchronously.
831  */
832 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
833 {
834 	unsigned long	flags;
835 	int		rc;
836 
837 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
838 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
839 	if (rc)
840 		goto done;
841 
842 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
843 		;	/* Do nothing */
844 
845 	} else {				/* Status URB */
846 		if (!hcd->uses_new_polling)
847 			del_timer (&hcd->rh_timer);
848 		if (urb == hcd->status_urb) {
849 			hcd->status_urb = NULL;
850 			usb_hcd_unlink_urb_from_ep(hcd, urb);
851 			usb_hcd_giveback_urb(hcd, urb, status);
852 		}
853 	}
854  done:
855 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
856 	return rc;
857 }
858 
859 
860 /*-------------------------------------------------------------------------*/
861 
862 /**
863  * usb_bus_init - shared initialization code
864  * @bus: the bus structure being initialized
865  *
866  * This code is used to initialize a usb_bus structure, memory for which is
867  * separately managed.
868  */
869 static void usb_bus_init (struct usb_bus *bus)
870 {
871 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
872 
873 	bus->devnum_next = 1;
874 
875 	bus->root_hub = NULL;
876 	bus->busnum = -1;
877 	bus->bandwidth_allocated = 0;
878 	bus->bandwidth_int_reqs  = 0;
879 	bus->bandwidth_isoc_reqs = 0;
880 	mutex_init(&bus->devnum_next_mutex);
881 }
882 
883 /*-------------------------------------------------------------------------*/
884 
885 /**
886  * usb_register_bus - registers the USB host controller with the usb core
887  * @bus: pointer to the bus to register
888  *
889  * Context: task context, might sleep.
890  *
891  * Assigns a bus number, and links the controller into usbcore data
892  * structures so that it can be seen by scanning the bus list.
893  *
894  * Return: 0 if successful. A negative error code otherwise.
895  */
896 static int usb_register_bus(struct usb_bus *bus)
897 {
898 	int result = -E2BIG;
899 	int busnum;
900 
901 	mutex_lock(&usb_bus_idr_lock);
902 	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
903 	if (busnum < 0) {
904 		pr_err("%s: failed to get bus number\n", usbcore_name);
905 		goto error_find_busnum;
906 	}
907 	bus->busnum = busnum;
908 	mutex_unlock(&usb_bus_idr_lock);
909 
910 	usb_notify_add_bus(bus);
911 
912 	dev_info (bus->controller, "new USB bus registered, assigned bus "
913 		  "number %d\n", bus->busnum);
914 	return 0;
915 
916 error_find_busnum:
917 	mutex_unlock(&usb_bus_idr_lock);
918 	return result;
919 }
920 
921 /**
922  * usb_deregister_bus - deregisters the USB host controller
923  * @bus: pointer to the bus to deregister
924  *
925  * Context: task context, might sleep.
926  *
927  * Recycles the bus number, and unlinks the controller from usbcore data
928  * structures so that it won't be seen by scanning the bus list.
929  */
930 static void usb_deregister_bus (struct usb_bus *bus)
931 {
932 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
933 
934 	/*
935 	 * NOTE: make sure that all the devices are removed by the
936 	 * controller code, as well as having it call this when cleaning
937 	 * itself up
938 	 */
939 	mutex_lock(&usb_bus_idr_lock);
940 	idr_remove(&usb_bus_idr, bus->busnum);
941 	mutex_unlock(&usb_bus_idr_lock);
942 
943 	usb_notify_remove_bus(bus);
944 }
945 
946 /**
947  * register_root_hub - called by usb_add_hcd() to register a root hub
948  * @hcd: host controller for this root hub
949  *
950  * This function registers the root hub with the USB subsystem.  It sets up
951  * the device properly in the device tree and then calls usb_new_device()
952  * to register the usb device.  It also assigns the root hub's USB address
953  * (always 1).
954  *
955  * Return: 0 if successful. A negative error code otherwise.
956  */
957 static int register_root_hub(struct usb_hcd *hcd)
958 {
959 	struct device *parent_dev = hcd->self.controller;
960 	struct usb_device *usb_dev = hcd->self.root_hub;
961 	struct usb_device_descriptor *descr;
962 	const int devnum = 1;
963 	int retval;
964 
965 	usb_dev->devnum = devnum;
966 	usb_dev->bus->devnum_next = devnum + 1;
967 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
968 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
969 
970 	mutex_lock(&usb_bus_idr_lock);
971 
972 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
973 	descr = usb_get_device_descriptor(usb_dev);
974 	if (IS_ERR(descr)) {
975 		retval = PTR_ERR(descr);
976 		mutex_unlock(&usb_bus_idr_lock);
977 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
978 				dev_name(&usb_dev->dev), retval);
979 		return retval;
980 	}
981 	usb_dev->descriptor = *descr;
982 	kfree(descr);
983 
984 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
985 		retval = usb_get_bos_descriptor(usb_dev);
986 		if (!retval) {
987 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
988 		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
989 			mutex_unlock(&usb_bus_idr_lock);
990 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
991 					dev_name(&usb_dev->dev), retval);
992 			return retval;
993 		}
994 	}
995 
996 	retval = usb_new_device (usb_dev);
997 	if (retval) {
998 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
999 				dev_name(&usb_dev->dev), retval);
1000 	} else {
1001 		spin_lock_irq (&hcd_root_hub_lock);
1002 		hcd->rh_registered = 1;
1003 		spin_unlock_irq (&hcd_root_hub_lock);
1004 
1005 		/* Did the HC die before the root hub was registered? */
1006 		if (HCD_DEAD(hcd))
1007 			usb_hc_died (hcd);	/* This time clean up */
1008 	}
1009 	mutex_unlock(&usb_bus_idr_lock);
1010 
1011 	return retval;
1012 }
1013 
1014 /*
1015  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1016  * @bus: the bus which the root hub belongs to
1017  * @portnum: the port which is being resumed
1018  *
1019  * HCDs should call this function when they know that a resume signal is
1020  * being sent to a root-hub port.  The root hub will be prevented from
1021  * going into autosuspend until usb_hcd_end_port_resume() is called.
1022  *
1023  * The bus's private lock must be held by the caller.
1024  */
1025 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1026 {
1027 	unsigned bit = 1 << portnum;
1028 
1029 	if (!(bus->resuming_ports & bit)) {
1030 		bus->resuming_ports |= bit;
1031 		pm_runtime_get_noresume(&bus->root_hub->dev);
1032 	}
1033 }
1034 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1035 
1036 /*
1037  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1038  * @bus: the bus which the root hub belongs to
1039  * @portnum: the port which is being resumed
1040  *
1041  * HCDs should call this function when they know that a resume signal has
1042  * stopped being sent to a root-hub port.  The root hub will be allowed to
1043  * autosuspend again.
1044  *
1045  * The bus's private lock must be held by the caller.
1046  */
1047 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1048 {
1049 	unsigned bit = 1 << portnum;
1050 
1051 	if (bus->resuming_ports & bit) {
1052 		bus->resuming_ports &= ~bit;
1053 		pm_runtime_put_noidle(&bus->root_hub->dev);
1054 	}
1055 }
1056 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1057 
1058 /*-------------------------------------------------------------------------*/
1059 
1060 /**
1061  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1062  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1063  * @is_input: true iff the transaction sends data to the host
1064  * @isoc: true for isochronous transactions, false for interrupt ones
1065  * @bytecount: how many bytes in the transaction.
1066  *
1067  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1068  *
1069  * Note:
1070  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1071  * scheduled in software, this function is only used for such scheduling.
1072  */
1073 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1074 {
1075 	unsigned long	tmp;
1076 
1077 	switch (speed) {
1078 	case USB_SPEED_LOW: 	/* INTR only */
1079 		if (is_input) {
1080 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1081 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1082 		} else {
1083 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1084 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1085 		}
1086 	case USB_SPEED_FULL:	/* ISOC or INTR */
1087 		if (isoc) {
1088 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1089 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1090 		} else {
1091 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1092 			return 9107L + BW_HOST_DELAY + tmp;
1093 		}
1094 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1095 		/* FIXME adjust for input vs output */
1096 		if (isoc)
1097 			tmp = HS_NSECS_ISO (bytecount);
1098 		else
1099 			tmp = HS_NSECS (bytecount);
1100 		return tmp;
1101 	default:
1102 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1103 		return -1;
1104 	}
1105 }
1106 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1107 
1108 
1109 /*-------------------------------------------------------------------------*/
1110 
1111 /*
1112  * Generic HC operations.
1113  */
1114 
1115 /*-------------------------------------------------------------------------*/
1116 
1117 /**
1118  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1119  * @hcd: host controller to which @urb was submitted
1120  * @urb: URB being submitted
1121  *
1122  * Host controller drivers should call this routine in their enqueue()
1123  * method.  The HCD's private spinlock must be held and interrupts must
1124  * be disabled.  The actions carried out here are required for URB
1125  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1126  *
1127  * Return: 0 for no error, otherwise a negative error code (in which case
1128  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1129  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1130  * the private spinlock and returning.
1131  */
1132 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1133 {
1134 	int		rc = 0;
1135 
1136 	spin_lock(&hcd_urb_list_lock);
1137 
1138 	/* Check that the URB isn't being killed */
1139 	if (unlikely(atomic_read(&urb->reject))) {
1140 		rc = -EPERM;
1141 		goto done;
1142 	}
1143 
1144 	if (unlikely(!urb->ep->enabled)) {
1145 		rc = -ENOENT;
1146 		goto done;
1147 	}
1148 
1149 	if (unlikely(!urb->dev->can_submit)) {
1150 		rc = -EHOSTUNREACH;
1151 		goto done;
1152 	}
1153 
1154 	/*
1155 	 * Check the host controller's state and add the URB to the
1156 	 * endpoint's queue.
1157 	 */
1158 	if (HCD_RH_RUNNING(hcd)) {
1159 		urb->unlinked = 0;
1160 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1161 	} else {
1162 		rc = -ESHUTDOWN;
1163 		goto done;
1164 	}
1165  done:
1166 	spin_unlock(&hcd_urb_list_lock);
1167 	return rc;
1168 }
1169 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1170 
1171 /**
1172  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1173  * @hcd: host controller to which @urb was submitted
1174  * @urb: URB being checked for unlinkability
1175  * @status: error code to store in @urb if the unlink succeeds
1176  *
1177  * Host controller drivers should call this routine in their dequeue()
1178  * method.  The HCD's private spinlock must be held and interrupts must
1179  * be disabled.  The actions carried out here are required for making
1180  * sure than an unlink is valid.
1181  *
1182  * Return: 0 for no error, otherwise a negative error code (in which case
1183  * the dequeue() method must fail).  The possible error codes are:
1184  *
1185  *	-EIDRM: @urb was not submitted or has already completed.
1186  *		The completion function may not have been called yet.
1187  *
1188  *	-EBUSY: @urb has already been unlinked.
1189  */
1190 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1191 		int status)
1192 {
1193 	struct list_head	*tmp;
1194 
1195 	/* insist the urb is still queued */
1196 	list_for_each(tmp, &urb->ep->urb_list) {
1197 		if (tmp == &urb->urb_list)
1198 			break;
1199 	}
1200 	if (tmp != &urb->urb_list)
1201 		return -EIDRM;
1202 
1203 	/* Any status except -EINPROGRESS means something already started to
1204 	 * unlink this URB from the hardware.  So there's no more work to do.
1205 	 */
1206 	if (urb->unlinked)
1207 		return -EBUSY;
1208 	urb->unlinked = status;
1209 	return 0;
1210 }
1211 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1212 
1213 /**
1214  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1215  * @hcd: host controller to which @urb was submitted
1216  * @urb: URB being unlinked
1217  *
1218  * Host controller drivers should call this routine before calling
1219  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1220  * interrupts must be disabled.  The actions carried out here are required
1221  * for URB completion.
1222  */
1223 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1224 {
1225 	/* clear all state linking urb to this dev (and hcd) */
1226 	spin_lock(&hcd_urb_list_lock);
1227 	list_del_init(&urb->urb_list);
1228 	spin_unlock(&hcd_urb_list_lock);
1229 }
1230 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1231 
1232 /*
1233  * Some usb host controllers can only perform dma using a small SRAM area,
1234  * or have restrictions on addressable DRAM.
1235  * The usb core itself is however optimized for host controllers that can dma
1236  * using regular system memory - like pci devices doing bus mastering.
1237  *
1238  * To support host controllers with limited dma capabilities we provide dma
1239  * bounce buffers. This feature can be enabled by initializing
1240  * hcd->localmem_pool using usb_hcd_setup_local_mem().
1241  *
1242  * The initialized hcd->localmem_pool then tells the usb code to allocate all
1243  * data for dma using the genalloc API.
1244  *
1245  * So, to summarize...
1246  *
1247  * - We need "local" memory, canonical example being
1248  *   a small SRAM on a discrete controller being the
1249  *   only memory that the controller can read ...
1250  *   (a) "normal" kernel memory is no good, and
1251  *   (b) there's not enough to share
1252  *
1253  * - So we use that, even though the primary requirement
1254  *   is that the memory be "local" (hence addressable
1255  *   by that device), not "coherent".
1256  *
1257  */
1258 
1259 static int hcd_alloc_coherent(struct usb_bus *bus,
1260 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1261 			      void **vaddr_handle, size_t size,
1262 			      enum dma_data_direction dir)
1263 {
1264 	unsigned char *vaddr;
1265 
1266 	if (*vaddr_handle == NULL) {
1267 		WARN_ON_ONCE(1);
1268 		return -EFAULT;
1269 	}
1270 
1271 	vaddr = hcd_buffer_alloc(bus, size + sizeof(unsigned long),
1272 				 mem_flags, dma_handle);
1273 	if (!vaddr)
1274 		return -ENOMEM;
1275 
1276 	/*
1277 	 * Store the virtual address of the buffer at the end
1278 	 * of the allocated dma buffer. The size of the buffer
1279 	 * may be uneven so use unaligned functions instead
1280 	 * of just rounding up. It makes sense to optimize for
1281 	 * memory footprint over access speed since the amount
1282 	 * of memory available for dma may be limited.
1283 	 */
1284 	put_unaligned((unsigned long)*vaddr_handle,
1285 		      (unsigned long *)(vaddr + size));
1286 
1287 	if (dir == DMA_TO_DEVICE)
1288 		memcpy(vaddr, *vaddr_handle, size);
1289 
1290 	*vaddr_handle = vaddr;
1291 	return 0;
1292 }
1293 
1294 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1295 			      void **vaddr_handle, size_t size,
1296 			      enum dma_data_direction dir)
1297 {
1298 	unsigned char *vaddr = *vaddr_handle;
1299 
1300 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1301 
1302 	if (dir == DMA_FROM_DEVICE)
1303 		memcpy(vaddr, *vaddr_handle, size);
1304 
1305 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1306 
1307 	*vaddr_handle = vaddr;
1308 	*dma_handle = 0;
1309 }
1310 
1311 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1312 {
1313 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1314 	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1315 		dma_unmap_single(hcd->self.sysdev,
1316 				urb->setup_dma,
1317 				sizeof(struct usb_ctrlrequest),
1318 				DMA_TO_DEVICE);
1319 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1320 		hcd_free_coherent(urb->dev->bus,
1321 				&urb->setup_dma,
1322 				(void **) &urb->setup_packet,
1323 				sizeof(struct usb_ctrlrequest),
1324 				DMA_TO_DEVICE);
1325 
1326 	/* Make it safe to call this routine more than once */
1327 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1328 }
1329 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1330 
1331 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1332 {
1333 	if (hcd->driver->unmap_urb_for_dma)
1334 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1335 	else
1336 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1337 }
1338 
1339 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1340 {
1341 	enum dma_data_direction dir;
1342 
1343 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1344 
1345 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1346 	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1347 	    (urb->transfer_flags & URB_DMA_MAP_SG))
1348 		dma_unmap_sg(hcd->self.sysdev,
1349 				urb->sg,
1350 				urb->num_sgs,
1351 				dir);
1352 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1353 		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1354 		dma_unmap_page(hcd->self.sysdev,
1355 				urb->transfer_dma,
1356 				urb->transfer_buffer_length,
1357 				dir);
1358 	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1359 		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1360 		dma_unmap_single(hcd->self.sysdev,
1361 				urb->transfer_dma,
1362 				urb->transfer_buffer_length,
1363 				dir);
1364 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1365 		hcd_free_coherent(urb->dev->bus,
1366 				&urb->transfer_dma,
1367 				&urb->transfer_buffer,
1368 				urb->transfer_buffer_length,
1369 				dir);
1370 
1371 	/* Make it safe to call this routine more than once */
1372 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1373 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1374 }
1375 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1376 
1377 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1378 			   gfp_t mem_flags)
1379 {
1380 	if (hcd->driver->map_urb_for_dma)
1381 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1382 	else
1383 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1384 }
1385 
1386 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1387 			    gfp_t mem_flags)
1388 {
1389 	enum dma_data_direction dir;
1390 	int ret = 0;
1391 
1392 	/* Map the URB's buffers for DMA access.
1393 	 * Lower level HCD code should use *_dma exclusively,
1394 	 * unless it uses pio or talks to another transport,
1395 	 * or uses the provided scatter gather list for bulk.
1396 	 */
1397 
1398 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1399 		if (hcd->self.uses_pio_for_control)
1400 			return ret;
1401 		if (hcd->localmem_pool) {
1402 			ret = hcd_alloc_coherent(
1403 					urb->dev->bus, mem_flags,
1404 					&urb->setup_dma,
1405 					(void **)&urb->setup_packet,
1406 					sizeof(struct usb_ctrlrequest),
1407 					DMA_TO_DEVICE);
1408 			if (ret)
1409 				return ret;
1410 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1411 		} else if (hcd_uses_dma(hcd)) {
1412 			if (object_is_on_stack(urb->setup_packet)) {
1413 				WARN_ONCE(1, "setup packet is on stack\n");
1414 				return -EAGAIN;
1415 			}
1416 
1417 			urb->setup_dma = dma_map_single(
1418 					hcd->self.sysdev,
1419 					urb->setup_packet,
1420 					sizeof(struct usb_ctrlrequest),
1421 					DMA_TO_DEVICE);
1422 			if (dma_mapping_error(hcd->self.sysdev,
1423 						urb->setup_dma))
1424 				return -EAGAIN;
1425 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1426 		}
1427 	}
1428 
1429 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1430 	if (urb->transfer_buffer_length != 0
1431 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1432 		if (hcd->localmem_pool) {
1433 			ret = hcd_alloc_coherent(
1434 					urb->dev->bus, mem_flags,
1435 					&urb->transfer_dma,
1436 					&urb->transfer_buffer,
1437 					urb->transfer_buffer_length,
1438 					dir);
1439 			if (ret == 0)
1440 				urb->transfer_flags |= URB_MAP_LOCAL;
1441 		} else if (hcd_uses_dma(hcd)) {
1442 			if (urb->num_sgs) {
1443 				int n;
1444 
1445 				/* We don't support sg for isoc transfers ! */
1446 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1447 					WARN_ON(1);
1448 					return -EINVAL;
1449 				}
1450 
1451 				n = dma_map_sg(
1452 						hcd->self.sysdev,
1453 						urb->sg,
1454 						urb->num_sgs,
1455 						dir);
1456 				if (!n)
1457 					ret = -EAGAIN;
1458 				else
1459 					urb->transfer_flags |= URB_DMA_MAP_SG;
1460 				urb->num_mapped_sgs = n;
1461 				if (n != urb->num_sgs)
1462 					urb->transfer_flags |=
1463 							URB_DMA_SG_COMBINED;
1464 			} else if (urb->sg) {
1465 				struct scatterlist *sg = urb->sg;
1466 				urb->transfer_dma = dma_map_page(
1467 						hcd->self.sysdev,
1468 						sg_page(sg),
1469 						sg->offset,
1470 						urb->transfer_buffer_length,
1471 						dir);
1472 				if (dma_mapping_error(hcd->self.sysdev,
1473 						urb->transfer_dma))
1474 					ret = -EAGAIN;
1475 				else
1476 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1477 			} else if (object_is_on_stack(urb->transfer_buffer)) {
1478 				WARN_ONCE(1, "transfer buffer is on stack\n");
1479 				ret = -EAGAIN;
1480 			} else {
1481 				urb->transfer_dma = dma_map_single(
1482 						hcd->self.sysdev,
1483 						urb->transfer_buffer,
1484 						urb->transfer_buffer_length,
1485 						dir);
1486 				if (dma_mapping_error(hcd->self.sysdev,
1487 						urb->transfer_dma))
1488 					ret = -EAGAIN;
1489 				else
1490 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1491 			}
1492 		}
1493 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1494 				URB_SETUP_MAP_LOCAL)))
1495 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1496 	}
1497 	return ret;
1498 }
1499 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1500 
1501 /*-------------------------------------------------------------------------*/
1502 
1503 /* may be called in any context with a valid urb->dev usecount
1504  * caller surrenders "ownership" of urb
1505  * expects usb_submit_urb() to have sanity checked and conditioned all
1506  * inputs in the urb
1507  */
1508 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1509 {
1510 	int			status;
1511 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1512 
1513 	/* increment urb's reference count as part of giving it to the HCD
1514 	 * (which will control it).  HCD guarantees that it either returns
1515 	 * an error or calls giveback(), but not both.
1516 	 */
1517 	usb_get_urb(urb);
1518 	atomic_inc(&urb->use_count);
1519 	atomic_inc(&urb->dev->urbnum);
1520 	usbmon_urb_submit(&hcd->self, urb);
1521 
1522 	/* NOTE requirements on root-hub callers (usbfs and the hub
1523 	 * driver, for now):  URBs' urb->transfer_buffer must be
1524 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1525 	 * they could clobber root hub response data.  Also, control
1526 	 * URBs must be submitted in process context with interrupts
1527 	 * enabled.
1528 	 */
1529 
1530 	if (is_root_hub(urb->dev)) {
1531 		status = rh_urb_enqueue(hcd, urb);
1532 	} else {
1533 		status = map_urb_for_dma(hcd, urb, mem_flags);
1534 		if (likely(status == 0)) {
1535 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1536 			if (unlikely(status))
1537 				unmap_urb_for_dma(hcd, urb);
1538 		}
1539 	}
1540 
1541 	if (unlikely(status)) {
1542 		usbmon_urb_submit_error(&hcd->self, urb, status);
1543 		urb->hcpriv = NULL;
1544 		INIT_LIST_HEAD(&urb->urb_list);
1545 		atomic_dec(&urb->use_count);
1546 		/*
1547 		 * Order the write of urb->use_count above before the read
1548 		 * of urb->reject below.  Pairs with the memory barriers in
1549 		 * usb_kill_urb() and usb_poison_urb().
1550 		 */
1551 		smp_mb__after_atomic();
1552 
1553 		atomic_dec(&urb->dev->urbnum);
1554 		if (atomic_read(&urb->reject))
1555 			wake_up(&usb_kill_urb_queue);
1556 		usb_put_urb(urb);
1557 	}
1558 	return status;
1559 }
1560 
1561 /*-------------------------------------------------------------------------*/
1562 
1563 /* this makes the hcd giveback() the urb more quickly, by kicking it
1564  * off hardware queues (which may take a while) and returning it as
1565  * soon as practical.  we've already set up the urb's return status,
1566  * but we can't know if the callback completed already.
1567  */
1568 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1569 {
1570 	int		value;
1571 
1572 	if (is_root_hub(urb->dev))
1573 		value = usb_rh_urb_dequeue(hcd, urb, status);
1574 	else {
1575 
1576 		/* The only reason an HCD might fail this call is if
1577 		 * it has not yet fully queued the urb to begin with.
1578 		 * Such failures should be harmless. */
1579 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1580 	}
1581 	return value;
1582 }
1583 
1584 /*
1585  * called in any context
1586  *
1587  * caller guarantees urb won't be recycled till both unlink()
1588  * and the urb's completion function return
1589  */
1590 int usb_hcd_unlink_urb (struct urb *urb, int status)
1591 {
1592 	struct usb_hcd		*hcd;
1593 	struct usb_device	*udev = urb->dev;
1594 	int			retval = -EIDRM;
1595 	unsigned long		flags;
1596 
1597 	/* Prevent the device and bus from going away while
1598 	 * the unlink is carried out.  If they are already gone
1599 	 * then urb->use_count must be 0, since disconnected
1600 	 * devices can't have any active URBs.
1601 	 */
1602 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1603 	if (atomic_read(&urb->use_count) > 0) {
1604 		retval = 0;
1605 		usb_get_dev(udev);
1606 	}
1607 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1608 	if (retval == 0) {
1609 		hcd = bus_to_hcd(urb->dev->bus);
1610 		retval = unlink1(hcd, urb, status);
1611 		if (retval == 0)
1612 			retval = -EINPROGRESS;
1613 		else if (retval != -EIDRM && retval != -EBUSY)
1614 			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1615 					urb, retval);
1616 		usb_put_dev(udev);
1617 	}
1618 	return retval;
1619 }
1620 
1621 /*-------------------------------------------------------------------------*/
1622 
1623 static void __usb_hcd_giveback_urb(struct urb *urb)
1624 {
1625 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1626 	struct usb_anchor *anchor = urb->anchor;
1627 	int status = urb->unlinked;
1628 
1629 	urb->hcpriv = NULL;
1630 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1631 	    urb->actual_length < urb->transfer_buffer_length &&
1632 	    !status))
1633 		status = -EREMOTEIO;
1634 
1635 	unmap_urb_for_dma(hcd, urb);
1636 	usbmon_urb_complete(&hcd->self, urb, status);
1637 	usb_anchor_suspend_wakeups(anchor);
1638 	usb_unanchor_urb(urb);
1639 	if (likely(status == 0))
1640 		usb_led_activity(USB_LED_EVENT_HOST);
1641 
1642 	/* pass ownership to the completion handler */
1643 	urb->status = status;
1644 	/*
1645 	 * This function can be called in task context inside another remote
1646 	 * coverage collection section, but kcov doesn't support that kind of
1647 	 * recursion yet. Only collect coverage in softirq context for now.
1648 	 */
1649 	kcov_remote_start_usb_softirq((u64)urb->dev->bus->busnum);
1650 	urb->complete(urb);
1651 	kcov_remote_stop_softirq();
1652 
1653 	usb_anchor_resume_wakeups(anchor);
1654 	atomic_dec(&urb->use_count);
1655 	/*
1656 	 * Order the write of urb->use_count above before the read
1657 	 * of urb->reject below.  Pairs with the memory barriers in
1658 	 * usb_kill_urb() and usb_poison_urb().
1659 	 */
1660 	smp_mb__after_atomic();
1661 
1662 	if (unlikely(atomic_read(&urb->reject)))
1663 		wake_up(&usb_kill_urb_queue);
1664 	usb_put_urb(urb);
1665 }
1666 
1667 static void usb_giveback_urb_bh(struct tasklet_struct *t)
1668 {
1669 	struct giveback_urb_bh *bh = from_tasklet(bh, t, bh);
1670 	struct list_head local_list;
1671 
1672 	spin_lock_irq(&bh->lock);
1673 	bh->running = true;
1674 	list_replace_init(&bh->head, &local_list);
1675 	spin_unlock_irq(&bh->lock);
1676 
1677 	while (!list_empty(&local_list)) {
1678 		struct urb *urb;
1679 
1680 		urb = list_entry(local_list.next, struct urb, urb_list);
1681 		list_del_init(&urb->urb_list);
1682 		bh->completing_ep = urb->ep;
1683 		__usb_hcd_giveback_urb(urb);
1684 		bh->completing_ep = NULL;
1685 	}
1686 
1687 	/*
1688 	 * giveback new URBs next time to prevent this function
1689 	 * from not exiting for a long time.
1690 	 */
1691 	spin_lock_irq(&bh->lock);
1692 	if (!list_empty(&bh->head)) {
1693 		if (bh->high_prio)
1694 			tasklet_hi_schedule(&bh->bh);
1695 		else
1696 			tasklet_schedule(&bh->bh);
1697 	}
1698 	bh->running = false;
1699 	spin_unlock_irq(&bh->lock);
1700 }
1701 
1702 /**
1703  * usb_hcd_giveback_urb - return URB from HCD to device driver
1704  * @hcd: host controller returning the URB
1705  * @urb: urb being returned to the USB device driver.
1706  * @status: completion status code for the URB.
1707  *
1708  * Context: atomic. The completion callback is invoked in caller's context.
1709  * For HCDs with HCD_BH flag set, the completion callback is invoked in tasklet
1710  * context (except for URBs submitted to the root hub which always complete in
1711  * caller's context).
1712  *
1713  * This hands the URB from HCD to its USB device driver, using its
1714  * completion function.  The HCD has freed all per-urb resources
1715  * (and is done using urb->hcpriv).  It also released all HCD locks;
1716  * the device driver won't cause problems if it frees, modifies,
1717  * or resubmits this URB.
1718  *
1719  * If @urb was unlinked, the value of @status will be overridden by
1720  * @urb->unlinked.  Erroneous short transfers are detected in case
1721  * the HCD hasn't checked for them.
1722  */
1723 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1724 {
1725 	struct giveback_urb_bh *bh;
1726 	bool running;
1727 
1728 	/* pass status to tasklet via unlinked */
1729 	if (likely(!urb->unlinked))
1730 		urb->unlinked = status;
1731 
1732 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1733 		__usb_hcd_giveback_urb(urb);
1734 		return;
1735 	}
1736 
1737 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe))
1738 		bh = &hcd->high_prio_bh;
1739 	else
1740 		bh = &hcd->low_prio_bh;
1741 
1742 	spin_lock(&bh->lock);
1743 	list_add_tail(&urb->urb_list, &bh->head);
1744 	running = bh->running;
1745 	spin_unlock(&bh->lock);
1746 
1747 	if (running)
1748 		;
1749 	else if (bh->high_prio)
1750 		tasklet_hi_schedule(&bh->bh);
1751 	else
1752 		tasklet_schedule(&bh->bh);
1753 }
1754 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1755 
1756 /*-------------------------------------------------------------------------*/
1757 
1758 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1759  * queue to drain completely.  The caller must first insure that no more
1760  * URBs can be submitted for this endpoint.
1761  */
1762 void usb_hcd_flush_endpoint(struct usb_device *udev,
1763 		struct usb_host_endpoint *ep)
1764 {
1765 	struct usb_hcd		*hcd;
1766 	struct urb		*urb;
1767 
1768 	if (!ep)
1769 		return;
1770 	might_sleep();
1771 	hcd = bus_to_hcd(udev->bus);
1772 
1773 	/* No more submits can occur */
1774 	spin_lock_irq(&hcd_urb_list_lock);
1775 rescan:
1776 	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1777 		int	is_in;
1778 
1779 		if (urb->unlinked)
1780 			continue;
1781 		usb_get_urb (urb);
1782 		is_in = usb_urb_dir_in(urb);
1783 		spin_unlock(&hcd_urb_list_lock);
1784 
1785 		/* kick hcd */
1786 		unlink1(hcd, urb, -ESHUTDOWN);
1787 		dev_dbg (hcd->self.controller,
1788 			"shutdown urb %pK ep%d%s-%s\n",
1789 			urb, usb_endpoint_num(&ep->desc),
1790 			is_in ? "in" : "out",
1791 			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1792 		usb_put_urb (urb);
1793 
1794 		/* list contents may have changed */
1795 		spin_lock(&hcd_urb_list_lock);
1796 		goto rescan;
1797 	}
1798 	spin_unlock_irq(&hcd_urb_list_lock);
1799 
1800 	/* Wait until the endpoint queue is completely empty */
1801 	while (!list_empty (&ep->urb_list)) {
1802 		spin_lock_irq(&hcd_urb_list_lock);
1803 
1804 		/* The list may have changed while we acquired the spinlock */
1805 		urb = NULL;
1806 		if (!list_empty (&ep->urb_list)) {
1807 			urb = list_entry (ep->urb_list.prev, struct urb,
1808 					urb_list);
1809 			usb_get_urb (urb);
1810 		}
1811 		spin_unlock_irq(&hcd_urb_list_lock);
1812 
1813 		if (urb) {
1814 			usb_kill_urb (urb);
1815 			usb_put_urb (urb);
1816 		}
1817 	}
1818 }
1819 
1820 /**
1821  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1822  *				the bus bandwidth
1823  * @udev: target &usb_device
1824  * @new_config: new configuration to install
1825  * @cur_alt: the current alternate interface setting
1826  * @new_alt: alternate interface setting that is being installed
1827  *
1828  * To change configurations, pass in the new configuration in new_config,
1829  * and pass NULL for cur_alt and new_alt.
1830  *
1831  * To reset a device's configuration (put the device in the ADDRESSED state),
1832  * pass in NULL for new_config, cur_alt, and new_alt.
1833  *
1834  * To change alternate interface settings, pass in NULL for new_config,
1835  * pass in the current alternate interface setting in cur_alt,
1836  * and pass in the new alternate interface setting in new_alt.
1837  *
1838  * Return: An error if the requested bandwidth change exceeds the
1839  * bus bandwidth or host controller internal resources.
1840  */
1841 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1842 		struct usb_host_config *new_config,
1843 		struct usb_host_interface *cur_alt,
1844 		struct usb_host_interface *new_alt)
1845 {
1846 	int num_intfs, i, j;
1847 	struct usb_host_interface *alt = NULL;
1848 	int ret = 0;
1849 	struct usb_hcd *hcd;
1850 	struct usb_host_endpoint *ep;
1851 
1852 	hcd = bus_to_hcd(udev->bus);
1853 	if (!hcd->driver->check_bandwidth)
1854 		return 0;
1855 
1856 	/* Configuration is being removed - set configuration 0 */
1857 	if (!new_config && !cur_alt) {
1858 		for (i = 1; i < 16; ++i) {
1859 			ep = udev->ep_out[i];
1860 			if (ep)
1861 				hcd->driver->drop_endpoint(hcd, udev, ep);
1862 			ep = udev->ep_in[i];
1863 			if (ep)
1864 				hcd->driver->drop_endpoint(hcd, udev, ep);
1865 		}
1866 		hcd->driver->check_bandwidth(hcd, udev);
1867 		return 0;
1868 	}
1869 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1870 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1871 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1872 	 * ok to exclude it.
1873 	 */
1874 	if (new_config) {
1875 		num_intfs = new_config->desc.bNumInterfaces;
1876 		/* Remove endpoints (except endpoint 0, which is always on the
1877 		 * schedule) from the old config from the schedule
1878 		 */
1879 		for (i = 1; i < 16; ++i) {
1880 			ep = udev->ep_out[i];
1881 			if (ep) {
1882 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1883 				if (ret < 0)
1884 					goto reset;
1885 			}
1886 			ep = udev->ep_in[i];
1887 			if (ep) {
1888 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1889 				if (ret < 0)
1890 					goto reset;
1891 			}
1892 		}
1893 		for (i = 0; i < num_intfs; ++i) {
1894 			struct usb_host_interface *first_alt;
1895 			int iface_num;
1896 
1897 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1898 			iface_num = first_alt->desc.bInterfaceNumber;
1899 			/* Set up endpoints for alternate interface setting 0 */
1900 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1901 			if (!alt)
1902 				/* No alt setting 0? Pick the first setting. */
1903 				alt = first_alt;
1904 
1905 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1906 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1907 				if (ret < 0)
1908 					goto reset;
1909 			}
1910 		}
1911 	}
1912 	if (cur_alt && new_alt) {
1913 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1914 				cur_alt->desc.bInterfaceNumber);
1915 
1916 		if (!iface)
1917 			return -EINVAL;
1918 		if (iface->resetting_device) {
1919 			/*
1920 			 * The USB core just reset the device, so the xHCI host
1921 			 * and the device will think alt setting 0 is installed.
1922 			 * However, the USB core will pass in the alternate
1923 			 * setting installed before the reset as cur_alt.  Dig
1924 			 * out the alternate setting 0 structure, or the first
1925 			 * alternate setting if a broken device doesn't have alt
1926 			 * setting 0.
1927 			 */
1928 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1929 			if (!cur_alt)
1930 				cur_alt = &iface->altsetting[0];
1931 		}
1932 
1933 		/* Drop all the endpoints in the current alt setting */
1934 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1935 			ret = hcd->driver->drop_endpoint(hcd, udev,
1936 					&cur_alt->endpoint[i]);
1937 			if (ret < 0)
1938 				goto reset;
1939 		}
1940 		/* Add all the endpoints in the new alt setting */
1941 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1942 			ret = hcd->driver->add_endpoint(hcd, udev,
1943 					&new_alt->endpoint[i]);
1944 			if (ret < 0)
1945 				goto reset;
1946 		}
1947 	}
1948 	ret = hcd->driver->check_bandwidth(hcd, udev);
1949 reset:
1950 	if (ret < 0)
1951 		hcd->driver->reset_bandwidth(hcd, udev);
1952 	return ret;
1953 }
1954 
1955 /* Disables the endpoint: synchronizes with the hcd to make sure all
1956  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1957  * have been called previously.  Use for set_configuration, set_interface,
1958  * driver removal, physical disconnect.
1959  *
1960  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1961  * type, maxpacket size, toggle, halt status, and scheduling.
1962  */
1963 void usb_hcd_disable_endpoint(struct usb_device *udev,
1964 		struct usb_host_endpoint *ep)
1965 {
1966 	struct usb_hcd		*hcd;
1967 
1968 	might_sleep();
1969 	hcd = bus_to_hcd(udev->bus);
1970 	if (hcd->driver->endpoint_disable)
1971 		hcd->driver->endpoint_disable(hcd, ep);
1972 }
1973 
1974 /**
1975  * usb_hcd_reset_endpoint - reset host endpoint state
1976  * @udev: USB device.
1977  * @ep:   the endpoint to reset.
1978  *
1979  * Resets any host endpoint state such as the toggle bit, sequence
1980  * number and current window.
1981  */
1982 void usb_hcd_reset_endpoint(struct usb_device *udev,
1983 			    struct usb_host_endpoint *ep)
1984 {
1985 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1986 
1987 	if (hcd->driver->endpoint_reset)
1988 		hcd->driver->endpoint_reset(hcd, ep);
1989 	else {
1990 		int epnum = usb_endpoint_num(&ep->desc);
1991 		int is_out = usb_endpoint_dir_out(&ep->desc);
1992 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1993 
1994 		usb_settoggle(udev, epnum, is_out, 0);
1995 		if (is_control)
1996 			usb_settoggle(udev, epnum, !is_out, 0);
1997 	}
1998 }
1999 
2000 /**
2001  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2002  * @interface:		alternate setting that includes all endpoints.
2003  * @eps:		array of endpoints that need streams.
2004  * @num_eps:		number of endpoints in the array.
2005  * @num_streams:	number of streams to allocate.
2006  * @mem_flags:		flags hcd should use to allocate memory.
2007  *
2008  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2009  * Drivers may queue multiple transfers to different stream IDs, which may
2010  * complete in a different order than they were queued.
2011  *
2012  * Return: On success, the number of allocated streams. On failure, a negative
2013  * error code.
2014  */
2015 int usb_alloc_streams(struct usb_interface *interface,
2016 		struct usb_host_endpoint **eps, unsigned int num_eps,
2017 		unsigned int num_streams, gfp_t mem_flags)
2018 {
2019 	struct usb_hcd *hcd;
2020 	struct usb_device *dev;
2021 	int i, ret;
2022 
2023 	dev = interface_to_usbdev(interface);
2024 	hcd = bus_to_hcd(dev->bus);
2025 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2026 		return -EINVAL;
2027 	if (dev->speed < USB_SPEED_SUPER)
2028 		return -EINVAL;
2029 	if (dev->state < USB_STATE_CONFIGURED)
2030 		return -ENODEV;
2031 
2032 	for (i = 0; i < num_eps; i++) {
2033 		/* Streams only apply to bulk endpoints. */
2034 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2035 			return -EINVAL;
2036 		/* Re-alloc is not allowed */
2037 		if (eps[i]->streams)
2038 			return -EINVAL;
2039 	}
2040 
2041 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2042 			num_streams, mem_flags);
2043 	if (ret < 0)
2044 		return ret;
2045 
2046 	for (i = 0; i < num_eps; i++)
2047 		eps[i]->streams = ret;
2048 
2049 	return ret;
2050 }
2051 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2052 
2053 /**
2054  * usb_free_streams - free bulk endpoint stream IDs.
2055  * @interface:	alternate setting that includes all endpoints.
2056  * @eps:	array of endpoints to remove streams from.
2057  * @num_eps:	number of endpoints in the array.
2058  * @mem_flags:	flags hcd should use to allocate memory.
2059  *
2060  * Reverts a group of bulk endpoints back to not using stream IDs.
2061  * Can fail if we are given bad arguments, or HCD is broken.
2062  *
2063  * Return: 0 on success. On failure, a negative error code.
2064  */
2065 int usb_free_streams(struct usb_interface *interface,
2066 		struct usb_host_endpoint **eps, unsigned int num_eps,
2067 		gfp_t mem_flags)
2068 {
2069 	struct usb_hcd *hcd;
2070 	struct usb_device *dev;
2071 	int i, ret;
2072 
2073 	dev = interface_to_usbdev(interface);
2074 	hcd = bus_to_hcd(dev->bus);
2075 	if (dev->speed < USB_SPEED_SUPER)
2076 		return -EINVAL;
2077 
2078 	/* Double-free is not allowed */
2079 	for (i = 0; i < num_eps; i++)
2080 		if (!eps[i] || !eps[i]->streams)
2081 			return -EINVAL;
2082 
2083 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2084 	if (ret < 0)
2085 		return ret;
2086 
2087 	for (i = 0; i < num_eps; i++)
2088 		eps[i]->streams = 0;
2089 
2090 	return ret;
2091 }
2092 EXPORT_SYMBOL_GPL(usb_free_streams);
2093 
2094 /* Protect against drivers that try to unlink URBs after the device
2095  * is gone, by waiting until all unlinks for @udev are finished.
2096  * Since we don't currently track URBs by device, simply wait until
2097  * nothing is running in the locked region of usb_hcd_unlink_urb().
2098  */
2099 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2100 {
2101 	spin_lock_irq(&hcd_urb_unlink_lock);
2102 	spin_unlock_irq(&hcd_urb_unlink_lock);
2103 }
2104 
2105 /*-------------------------------------------------------------------------*/
2106 
2107 /* called in any context */
2108 int usb_hcd_get_frame_number (struct usb_device *udev)
2109 {
2110 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2111 
2112 	if (!HCD_RH_RUNNING(hcd))
2113 		return -ESHUTDOWN;
2114 	return hcd->driver->get_frame_number (hcd);
2115 }
2116 
2117 /*-------------------------------------------------------------------------*/
2118 #ifdef CONFIG_USB_HCD_TEST_MODE
2119 
2120 static void usb_ehset_completion(struct urb *urb)
2121 {
2122 	struct completion  *done = urb->context;
2123 
2124 	complete(done);
2125 }
2126 /*
2127  * Allocate and initialize a control URB. This request will be used by the
2128  * EHSET SINGLE_STEP_SET_FEATURE test in which the DATA and STATUS stages
2129  * of the GetDescriptor request are sent 15 seconds after the SETUP stage.
2130  * Return NULL if failed.
2131  */
2132 static struct urb *request_single_step_set_feature_urb(
2133 	struct usb_device	*udev,
2134 	void			*dr,
2135 	void			*buf,
2136 	struct completion	*done)
2137 {
2138 	struct urb *urb;
2139 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2140 
2141 	urb = usb_alloc_urb(0, GFP_KERNEL);
2142 	if (!urb)
2143 		return NULL;
2144 
2145 	urb->pipe = usb_rcvctrlpipe(udev, 0);
2146 
2147 	urb->ep = &udev->ep0;
2148 	urb->dev = udev;
2149 	urb->setup_packet = (void *)dr;
2150 	urb->transfer_buffer = buf;
2151 	urb->transfer_buffer_length = USB_DT_DEVICE_SIZE;
2152 	urb->complete = usb_ehset_completion;
2153 	urb->status = -EINPROGRESS;
2154 	urb->actual_length = 0;
2155 	urb->transfer_flags = URB_DIR_IN;
2156 	usb_get_urb(urb);
2157 	atomic_inc(&urb->use_count);
2158 	atomic_inc(&urb->dev->urbnum);
2159 	if (map_urb_for_dma(hcd, urb, GFP_KERNEL)) {
2160 		usb_put_urb(urb);
2161 		usb_free_urb(urb);
2162 		return NULL;
2163 	}
2164 
2165 	urb->context = done;
2166 	return urb;
2167 }
2168 
2169 int ehset_single_step_set_feature(struct usb_hcd *hcd, int port)
2170 {
2171 	int retval = -ENOMEM;
2172 	struct usb_ctrlrequest *dr;
2173 	struct urb *urb;
2174 	struct usb_device *udev;
2175 	struct usb_device_descriptor *buf;
2176 	DECLARE_COMPLETION_ONSTACK(done);
2177 
2178 	/* Obtain udev of the rhub's child port */
2179 	udev = usb_hub_find_child(hcd->self.root_hub, port);
2180 	if (!udev) {
2181 		dev_err(hcd->self.controller, "No device attached to the RootHub\n");
2182 		return -ENODEV;
2183 	}
2184 	buf = kmalloc(USB_DT_DEVICE_SIZE, GFP_KERNEL);
2185 	if (!buf)
2186 		return -ENOMEM;
2187 
2188 	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
2189 	if (!dr) {
2190 		kfree(buf);
2191 		return -ENOMEM;
2192 	}
2193 
2194 	/* Fill Setup packet for GetDescriptor */
2195 	dr->bRequestType = USB_DIR_IN;
2196 	dr->bRequest = USB_REQ_GET_DESCRIPTOR;
2197 	dr->wValue = cpu_to_le16(USB_DT_DEVICE << 8);
2198 	dr->wIndex = 0;
2199 	dr->wLength = cpu_to_le16(USB_DT_DEVICE_SIZE);
2200 	urb = request_single_step_set_feature_urb(udev, dr, buf, &done);
2201 	if (!urb)
2202 		goto cleanup;
2203 
2204 	/* Submit just the SETUP stage */
2205 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 1);
2206 	if (retval)
2207 		goto out1;
2208 	if (!wait_for_completion_timeout(&done, msecs_to_jiffies(2000))) {
2209 		usb_kill_urb(urb);
2210 		retval = -ETIMEDOUT;
2211 		dev_err(hcd->self.controller,
2212 			"%s SETUP stage timed out on ep0\n", __func__);
2213 		goto out1;
2214 	}
2215 	msleep(15 * 1000);
2216 
2217 	/* Complete remaining DATA and STATUS stages using the same URB */
2218 	urb->status = -EINPROGRESS;
2219 	usb_get_urb(urb);
2220 	atomic_inc(&urb->use_count);
2221 	atomic_inc(&urb->dev->urbnum);
2222 	retval = hcd->driver->submit_single_step_set_feature(hcd, urb, 0);
2223 	if (!retval && !wait_for_completion_timeout(&done,
2224 						msecs_to_jiffies(2000))) {
2225 		usb_kill_urb(urb);
2226 		retval = -ETIMEDOUT;
2227 		dev_err(hcd->self.controller,
2228 			"%s IN stage timed out on ep0\n", __func__);
2229 	}
2230 out1:
2231 	usb_free_urb(urb);
2232 cleanup:
2233 	kfree(dr);
2234 	kfree(buf);
2235 	return retval;
2236 }
2237 EXPORT_SYMBOL_GPL(ehset_single_step_set_feature);
2238 #endif /* CONFIG_USB_HCD_TEST_MODE */
2239 
2240 /*-------------------------------------------------------------------------*/
2241 
2242 #ifdef	CONFIG_PM
2243 
2244 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2245 {
2246 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2247 	int		status;
2248 	int		old_state = hcd->state;
2249 
2250 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2251 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2252 			rhdev->do_remote_wakeup);
2253 	if (HCD_DEAD(hcd)) {
2254 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2255 		return 0;
2256 	}
2257 
2258 	if (!hcd->driver->bus_suspend) {
2259 		status = -ENOENT;
2260 	} else {
2261 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2262 		hcd->state = HC_STATE_QUIESCING;
2263 		status = hcd->driver->bus_suspend(hcd);
2264 	}
2265 	if (status == 0) {
2266 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2267 		hcd->state = HC_STATE_SUSPENDED;
2268 
2269 		if (!PMSG_IS_AUTO(msg))
2270 			usb_phy_roothub_suspend(hcd->self.sysdev,
2271 						hcd->phy_roothub);
2272 
2273 		/* Did we race with a root-hub wakeup event? */
2274 		if (rhdev->do_remote_wakeup) {
2275 			char	buffer[6];
2276 
2277 			status = hcd->driver->hub_status_data(hcd, buffer);
2278 			if (status != 0) {
2279 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2280 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2281 				status = -EBUSY;
2282 			}
2283 		}
2284 	} else {
2285 		spin_lock_irq(&hcd_root_hub_lock);
2286 		if (!HCD_DEAD(hcd)) {
2287 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2288 			hcd->state = old_state;
2289 		}
2290 		spin_unlock_irq(&hcd_root_hub_lock);
2291 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2292 				"suspend", status);
2293 	}
2294 	return status;
2295 }
2296 
2297 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2298 {
2299 	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2300 	int		status;
2301 	int		old_state = hcd->state;
2302 
2303 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2304 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2305 	if (HCD_DEAD(hcd)) {
2306 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2307 		return 0;
2308 	}
2309 
2310 	if (!PMSG_IS_AUTO(msg)) {
2311 		status = usb_phy_roothub_resume(hcd->self.sysdev,
2312 						hcd->phy_roothub);
2313 		if (status)
2314 			return status;
2315 	}
2316 
2317 	if (!hcd->driver->bus_resume)
2318 		return -ENOENT;
2319 	if (HCD_RH_RUNNING(hcd))
2320 		return 0;
2321 
2322 	hcd->state = HC_STATE_RESUMING;
2323 	status = hcd->driver->bus_resume(hcd);
2324 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2325 	if (status == 0)
2326 		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2327 
2328 	if (status == 0) {
2329 		struct usb_device *udev;
2330 		int port1;
2331 
2332 		spin_lock_irq(&hcd_root_hub_lock);
2333 		if (!HCD_DEAD(hcd)) {
2334 			usb_set_device_state(rhdev, rhdev->actconfig
2335 					? USB_STATE_CONFIGURED
2336 					: USB_STATE_ADDRESS);
2337 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2338 			hcd->state = HC_STATE_RUNNING;
2339 		}
2340 		spin_unlock_irq(&hcd_root_hub_lock);
2341 
2342 		/*
2343 		 * Check whether any of the enabled ports on the root hub are
2344 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2345 		 * (this is what the USB-2 spec calls a "global resume").
2346 		 * Otherwise we can skip the delay.
2347 		 */
2348 		usb_hub_for_each_child(rhdev, port1, udev) {
2349 			if (udev->state != USB_STATE_NOTATTACHED &&
2350 					!udev->port_is_suspended) {
2351 				usleep_range(10000, 11000);	/* TRSMRCY */
2352 				break;
2353 			}
2354 		}
2355 	} else {
2356 		hcd->state = old_state;
2357 		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2358 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2359 				"resume", status);
2360 		if (status != -ESHUTDOWN)
2361 			usb_hc_died(hcd);
2362 	}
2363 	return status;
2364 }
2365 
2366 /* Workqueue routine for root-hub remote wakeup */
2367 static void hcd_resume_work(struct work_struct *work)
2368 {
2369 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2370 	struct usb_device *udev = hcd->self.root_hub;
2371 
2372 	usb_remote_wakeup(udev);
2373 }
2374 
2375 /**
2376  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2377  * @hcd: host controller for this root hub
2378  *
2379  * The USB host controller calls this function when its root hub is
2380  * suspended (with the remote wakeup feature enabled) and a remote
2381  * wakeup request is received.  The routine submits a workqueue request
2382  * to resume the root hub (that is, manage its downstream ports again).
2383  */
2384 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2385 {
2386 	unsigned long flags;
2387 
2388 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2389 	if (hcd->rh_registered) {
2390 		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2391 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2392 		queue_work(pm_wq, &hcd->wakeup_work);
2393 	}
2394 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2395 }
2396 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2397 
2398 #endif	/* CONFIG_PM */
2399 
2400 /*-------------------------------------------------------------------------*/
2401 
2402 #ifdef	CONFIG_USB_OTG
2403 
2404 /**
2405  * usb_bus_start_enum - start immediate enumeration (for OTG)
2406  * @bus: the bus (must use hcd framework)
2407  * @port_num: 1-based number of port; usually bus->otg_port
2408  * Context: atomic
2409  *
2410  * Starts enumeration, with an immediate reset followed later by
2411  * hub_wq identifying and possibly configuring the device.
2412  * This is needed by OTG controller drivers, where it helps meet
2413  * HNP protocol timing requirements for starting a port reset.
2414  *
2415  * Return: 0 if successful.
2416  */
2417 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2418 {
2419 	struct usb_hcd		*hcd;
2420 	int			status = -EOPNOTSUPP;
2421 
2422 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2423 	 * boards with root hubs hooked up to internal devices (instead of
2424 	 * just the OTG port) may need more attention to resetting...
2425 	 */
2426 	hcd = bus_to_hcd(bus);
2427 	if (port_num && hcd->driver->start_port_reset)
2428 		status = hcd->driver->start_port_reset(hcd, port_num);
2429 
2430 	/* allocate hub_wq shortly after (first) root port reset finishes;
2431 	 * it may issue others, until at least 50 msecs have passed.
2432 	 */
2433 	if (status == 0)
2434 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2435 	return status;
2436 }
2437 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2438 
2439 #endif
2440 
2441 /*-------------------------------------------------------------------------*/
2442 
2443 /**
2444  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2445  * @irq: the IRQ being raised
2446  * @__hcd: pointer to the HCD whose IRQ is being signaled
2447  *
2448  * If the controller isn't HALTed, calls the driver's irq handler.
2449  * Checks whether the controller is now dead.
2450  *
2451  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2452  */
2453 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2454 {
2455 	struct usb_hcd		*hcd = __hcd;
2456 	irqreturn_t		rc;
2457 
2458 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2459 		rc = IRQ_NONE;
2460 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2461 		rc = IRQ_NONE;
2462 	else
2463 		rc = IRQ_HANDLED;
2464 
2465 	return rc;
2466 }
2467 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2468 
2469 /*-------------------------------------------------------------------------*/
2470 
2471 /* Workqueue routine for when the root-hub has died. */
2472 static void hcd_died_work(struct work_struct *work)
2473 {
2474 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2475 	static char *env[] = {
2476 		"ERROR=DEAD",
2477 		NULL
2478 	};
2479 
2480 	/* Notify user space that the host controller has died */
2481 	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2482 }
2483 
2484 /**
2485  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2486  * @hcd: pointer to the HCD representing the controller
2487  *
2488  * This is called by bus glue to report a USB host controller that died
2489  * while operations may still have been pending.  It's called automatically
2490  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2491  *
2492  * Only call this function with the primary HCD.
2493  */
2494 void usb_hc_died (struct usb_hcd *hcd)
2495 {
2496 	unsigned long flags;
2497 
2498 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2499 
2500 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2501 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2502 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2503 	if (hcd->rh_registered) {
2504 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2505 
2506 		/* make hub_wq clean up old urbs and devices */
2507 		usb_set_device_state (hcd->self.root_hub,
2508 				USB_STATE_NOTATTACHED);
2509 		usb_kick_hub_wq(hcd->self.root_hub);
2510 	}
2511 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2512 		hcd = hcd->shared_hcd;
2513 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2514 		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2515 		if (hcd->rh_registered) {
2516 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2517 
2518 			/* make hub_wq clean up old urbs and devices */
2519 			usb_set_device_state(hcd->self.root_hub,
2520 					USB_STATE_NOTATTACHED);
2521 			usb_kick_hub_wq(hcd->self.root_hub);
2522 		}
2523 	}
2524 
2525 	/* Handle the case where this function gets called with a shared HCD */
2526 	if (usb_hcd_is_primary_hcd(hcd))
2527 		schedule_work(&hcd->died_work);
2528 	else
2529 		schedule_work(&hcd->primary_hcd->died_work);
2530 
2531 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2532 	/* Make sure that the other roothub is also deallocated. */
2533 }
2534 EXPORT_SYMBOL_GPL (usb_hc_died);
2535 
2536 /*-------------------------------------------------------------------------*/
2537 
2538 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2539 {
2540 
2541 	spin_lock_init(&bh->lock);
2542 	INIT_LIST_HEAD(&bh->head);
2543 	tasklet_setup(&bh->bh, usb_giveback_urb_bh);
2544 }
2545 
2546 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2547 		struct device *sysdev, struct device *dev, const char *bus_name,
2548 		struct usb_hcd *primary_hcd)
2549 {
2550 	struct usb_hcd *hcd;
2551 
2552 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2553 	if (!hcd)
2554 		return NULL;
2555 	if (primary_hcd == NULL) {
2556 		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2557 				GFP_KERNEL);
2558 		if (!hcd->address0_mutex) {
2559 			kfree(hcd);
2560 			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2561 			return NULL;
2562 		}
2563 		mutex_init(hcd->address0_mutex);
2564 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2565 				GFP_KERNEL);
2566 		if (!hcd->bandwidth_mutex) {
2567 			kfree(hcd->address0_mutex);
2568 			kfree(hcd);
2569 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2570 			return NULL;
2571 		}
2572 		mutex_init(hcd->bandwidth_mutex);
2573 		dev_set_drvdata(dev, hcd);
2574 	} else {
2575 		mutex_lock(&usb_port_peer_mutex);
2576 		hcd->address0_mutex = primary_hcd->address0_mutex;
2577 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2578 		hcd->primary_hcd = primary_hcd;
2579 		primary_hcd->primary_hcd = primary_hcd;
2580 		hcd->shared_hcd = primary_hcd;
2581 		primary_hcd->shared_hcd = hcd;
2582 		mutex_unlock(&usb_port_peer_mutex);
2583 	}
2584 
2585 	kref_init(&hcd->kref);
2586 
2587 	usb_bus_init(&hcd->self);
2588 	hcd->self.controller = dev;
2589 	hcd->self.sysdev = sysdev;
2590 	hcd->self.bus_name = bus_name;
2591 
2592 	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2593 #ifdef CONFIG_PM
2594 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2595 #endif
2596 
2597 	INIT_WORK(&hcd->died_work, hcd_died_work);
2598 
2599 	hcd->driver = driver;
2600 	hcd->speed = driver->flags & HCD_MASK;
2601 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2602 			"USB Host Controller";
2603 	return hcd;
2604 }
2605 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2606 
2607 /**
2608  * usb_create_shared_hcd - create and initialize an HCD structure
2609  * @driver: HC driver that will use this hcd
2610  * @dev: device for this HC, stored in hcd->self.controller
2611  * @bus_name: value to store in hcd->self.bus_name
2612  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2613  *              PCI device.  Only allocate certain resources for the primary HCD
2614  *
2615  * Context: task context, might sleep.
2616  *
2617  * Allocate a struct usb_hcd, with extra space at the end for the
2618  * HC driver's private data.  Initialize the generic members of the
2619  * hcd structure.
2620  *
2621  * Return: On success, a pointer to the created and initialized HCD structure.
2622  * On failure (e.g. if memory is unavailable), %NULL.
2623  */
2624 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2625 		struct device *dev, const char *bus_name,
2626 		struct usb_hcd *primary_hcd)
2627 {
2628 	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2629 }
2630 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2631 
2632 /**
2633  * usb_create_hcd - create and initialize an HCD structure
2634  * @driver: HC driver that will use this hcd
2635  * @dev: device for this HC, stored in hcd->self.controller
2636  * @bus_name: value to store in hcd->self.bus_name
2637  *
2638  * Context: task context, might sleep.
2639  *
2640  * Allocate a struct usb_hcd, with extra space at the end for the
2641  * HC driver's private data.  Initialize the generic members of the
2642  * hcd structure.
2643  *
2644  * Return: On success, a pointer to the created and initialized HCD
2645  * structure. On failure (e.g. if memory is unavailable), %NULL.
2646  */
2647 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2648 		struct device *dev, const char *bus_name)
2649 {
2650 	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2651 }
2652 EXPORT_SYMBOL_GPL(usb_create_hcd);
2653 
2654 /*
2655  * Roothubs that share one PCI device must also share the bandwidth mutex.
2656  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2657  * deallocated.
2658  *
2659  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2660  * freed.  When hcd_release() is called for either hcd in a peer set,
2661  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2662  */
2663 static void hcd_release(struct kref *kref)
2664 {
2665 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2666 
2667 	mutex_lock(&usb_port_peer_mutex);
2668 	if (hcd->shared_hcd) {
2669 		struct usb_hcd *peer = hcd->shared_hcd;
2670 
2671 		peer->shared_hcd = NULL;
2672 		peer->primary_hcd = NULL;
2673 	} else {
2674 		kfree(hcd->address0_mutex);
2675 		kfree(hcd->bandwidth_mutex);
2676 	}
2677 	mutex_unlock(&usb_port_peer_mutex);
2678 	kfree(hcd);
2679 }
2680 
2681 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2682 {
2683 	if (hcd)
2684 		kref_get (&hcd->kref);
2685 	return hcd;
2686 }
2687 EXPORT_SYMBOL_GPL(usb_get_hcd);
2688 
2689 void usb_put_hcd (struct usb_hcd *hcd)
2690 {
2691 	if (hcd)
2692 		kref_put (&hcd->kref, hcd_release);
2693 }
2694 EXPORT_SYMBOL_GPL(usb_put_hcd);
2695 
2696 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2697 {
2698 	if (!hcd->primary_hcd)
2699 		return 1;
2700 	return hcd == hcd->primary_hcd;
2701 }
2702 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2703 
2704 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2705 {
2706 	if (!hcd->driver->find_raw_port_number)
2707 		return port1;
2708 
2709 	return hcd->driver->find_raw_port_number(hcd, port1);
2710 }
2711 
2712 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2713 		unsigned int irqnum, unsigned long irqflags)
2714 {
2715 	int retval;
2716 
2717 	if (hcd->driver->irq) {
2718 
2719 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2720 				hcd->driver->description, hcd->self.busnum);
2721 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2722 				hcd->irq_descr, hcd);
2723 		if (retval != 0) {
2724 			dev_err(hcd->self.controller,
2725 					"request interrupt %d failed\n",
2726 					irqnum);
2727 			return retval;
2728 		}
2729 		hcd->irq = irqnum;
2730 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2731 				(hcd->driver->flags & HCD_MEMORY) ?
2732 					"io mem" : "io port",
2733 				(unsigned long long)hcd->rsrc_start);
2734 	} else {
2735 		hcd->irq = 0;
2736 		if (hcd->rsrc_start)
2737 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2738 					(hcd->driver->flags & HCD_MEMORY) ?
2739 						"io mem" : "io port",
2740 					(unsigned long long)hcd->rsrc_start);
2741 	}
2742 	return 0;
2743 }
2744 
2745 /*
2746  * Before we free this root hub, flush in-flight peering attempts
2747  * and disable peer lookups
2748  */
2749 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2750 {
2751 	struct usb_device *rhdev;
2752 
2753 	mutex_lock(&usb_port_peer_mutex);
2754 	rhdev = hcd->self.root_hub;
2755 	hcd->self.root_hub = NULL;
2756 	mutex_unlock(&usb_port_peer_mutex);
2757 	usb_put_dev(rhdev);
2758 }
2759 
2760 /**
2761  * usb_stop_hcd - Halt the HCD
2762  * @hcd: the usb_hcd that has to be halted
2763  *
2764  * Stop the root-hub polling timer and invoke the HCD's ->stop callback.
2765  */
2766 static void usb_stop_hcd(struct usb_hcd *hcd)
2767 {
2768 	hcd->rh_pollable = 0;
2769 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2770 	del_timer_sync(&hcd->rh_timer);
2771 
2772 	hcd->driver->stop(hcd);
2773 	hcd->state = HC_STATE_HALT;
2774 
2775 	/* In case the HCD restarted the timer, stop it again. */
2776 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2777 	del_timer_sync(&hcd->rh_timer);
2778 }
2779 
2780 /**
2781  * usb_add_hcd - finish generic HCD structure initialization and register
2782  * @hcd: the usb_hcd structure to initialize
2783  * @irqnum: Interrupt line to allocate
2784  * @irqflags: Interrupt type flags
2785  *
2786  * Finish the remaining parts of generic HCD initialization: allocate the
2787  * buffers of consistent memory, register the bus, request the IRQ line,
2788  * and call the driver's reset() and start() routines.
2789  */
2790 int usb_add_hcd(struct usb_hcd *hcd,
2791 		unsigned int irqnum, unsigned long irqflags)
2792 {
2793 	int retval;
2794 	struct usb_device *rhdev;
2795 	struct usb_hcd *shared_hcd;
2796 
2797 	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2798 		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2799 		if (IS_ERR(hcd->phy_roothub))
2800 			return PTR_ERR(hcd->phy_roothub);
2801 
2802 		retval = usb_phy_roothub_init(hcd->phy_roothub);
2803 		if (retval)
2804 			return retval;
2805 
2806 		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2807 						  PHY_MODE_USB_HOST_SS);
2808 		if (retval)
2809 			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2810 							  PHY_MODE_USB_HOST);
2811 		if (retval)
2812 			goto err_usb_phy_roothub_power_on;
2813 
2814 		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2815 		if (retval)
2816 			goto err_usb_phy_roothub_power_on;
2817 	}
2818 
2819 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2820 
2821 	switch (authorized_default) {
2822 	case USB_AUTHORIZE_NONE:
2823 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2824 		break;
2825 
2826 	case USB_AUTHORIZE_INTERNAL:
2827 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2828 		break;
2829 
2830 	case USB_AUTHORIZE_ALL:
2831 	case USB_AUTHORIZE_WIRED:
2832 	default:
2833 		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2834 		break;
2835 	}
2836 
2837 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2838 
2839 	/* per default all interfaces are authorized */
2840 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2841 
2842 	/* HC is in reset state, but accessible.  Now do the one-time init,
2843 	 * bottom up so that hcds can customize the root hubs before hub_wq
2844 	 * starts talking to them.  (Note, bus id is assigned early too.)
2845 	 */
2846 	retval = hcd_buffer_create(hcd);
2847 	if (retval != 0) {
2848 		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2849 		goto err_create_buf;
2850 	}
2851 
2852 	retval = usb_register_bus(&hcd->self);
2853 	if (retval < 0)
2854 		goto err_register_bus;
2855 
2856 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2857 	if (rhdev == NULL) {
2858 		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2859 		retval = -ENOMEM;
2860 		goto err_allocate_root_hub;
2861 	}
2862 	mutex_lock(&usb_port_peer_mutex);
2863 	hcd->self.root_hub = rhdev;
2864 	mutex_unlock(&usb_port_peer_mutex);
2865 
2866 	rhdev->rx_lanes = 1;
2867 	rhdev->tx_lanes = 1;
2868 	rhdev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2869 
2870 	switch (hcd->speed) {
2871 	case HCD_USB11:
2872 		rhdev->speed = USB_SPEED_FULL;
2873 		break;
2874 	case HCD_USB2:
2875 		rhdev->speed = USB_SPEED_HIGH;
2876 		break;
2877 	case HCD_USB3:
2878 		rhdev->speed = USB_SPEED_SUPER;
2879 		break;
2880 	case HCD_USB32:
2881 		rhdev->rx_lanes = 2;
2882 		rhdev->tx_lanes = 2;
2883 		rhdev->ssp_rate = USB_SSP_GEN_2x2;
2884 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2885 		break;
2886 	case HCD_USB31:
2887 		rhdev->ssp_rate = USB_SSP_GEN_2x1;
2888 		rhdev->speed = USB_SPEED_SUPER_PLUS;
2889 		break;
2890 	default:
2891 		retval = -EINVAL;
2892 		goto err_set_rh_speed;
2893 	}
2894 
2895 	/* wakeup flag init defaults to "everything works" for root hubs,
2896 	 * but drivers can override it in reset() if needed, along with
2897 	 * recording the overall controller's system wakeup capability.
2898 	 */
2899 	device_set_wakeup_capable(&rhdev->dev, 1);
2900 
2901 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2902 	 * registered.  But since the controller can die at any time,
2903 	 * let's initialize the flag before touching the hardware.
2904 	 */
2905 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2906 
2907 	/* "reset" is misnamed; its role is now one-time init. the controller
2908 	 * should already have been reset (and boot firmware kicked off etc).
2909 	 */
2910 	if (hcd->driver->reset) {
2911 		retval = hcd->driver->reset(hcd);
2912 		if (retval < 0) {
2913 			dev_err(hcd->self.controller, "can't setup: %d\n",
2914 					retval);
2915 			goto err_hcd_driver_setup;
2916 		}
2917 	}
2918 	hcd->rh_pollable = 1;
2919 
2920 	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2921 	if (retval)
2922 		goto err_hcd_driver_setup;
2923 
2924 	/* NOTE: root hub and controller capabilities may not be the same */
2925 	if (device_can_wakeup(hcd->self.controller)
2926 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2927 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2928 
2929 	/* initialize tasklets */
2930 	init_giveback_urb_bh(&hcd->high_prio_bh);
2931 	hcd->high_prio_bh.high_prio = true;
2932 	init_giveback_urb_bh(&hcd->low_prio_bh);
2933 
2934 	/* enable irqs just before we start the controller,
2935 	 * if the BIOS provides legacy PCI irqs.
2936 	 */
2937 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2938 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2939 		if (retval)
2940 			goto err_request_irq;
2941 	}
2942 
2943 	hcd->state = HC_STATE_RUNNING;
2944 	retval = hcd->driver->start(hcd);
2945 	if (retval < 0) {
2946 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2947 		goto err_hcd_driver_start;
2948 	}
2949 
2950 	/* starting here, usbcore will pay attention to the shared HCD roothub */
2951 	shared_hcd = hcd->shared_hcd;
2952 	if (!usb_hcd_is_primary_hcd(hcd) && shared_hcd && HCD_DEFER_RH_REGISTER(shared_hcd)) {
2953 		retval = register_root_hub(shared_hcd);
2954 		if (retval != 0)
2955 			goto err_register_root_hub;
2956 
2957 		if (shared_hcd->uses_new_polling && HCD_POLL_RH(shared_hcd))
2958 			usb_hcd_poll_rh_status(shared_hcd);
2959 	}
2960 
2961 	/* starting here, usbcore will pay attention to this root hub */
2962 	if (!HCD_DEFER_RH_REGISTER(hcd)) {
2963 		retval = register_root_hub(hcd);
2964 		if (retval != 0)
2965 			goto err_register_root_hub;
2966 
2967 		if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2968 			usb_hcd_poll_rh_status(hcd);
2969 	}
2970 
2971 	return retval;
2972 
2973 err_register_root_hub:
2974 	usb_stop_hcd(hcd);
2975 err_hcd_driver_start:
2976 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2977 		free_irq(irqnum, hcd);
2978 err_request_irq:
2979 err_hcd_driver_setup:
2980 err_set_rh_speed:
2981 	usb_put_invalidate_rhdev(hcd);
2982 err_allocate_root_hub:
2983 	usb_deregister_bus(&hcd->self);
2984 err_register_bus:
2985 	hcd_buffer_destroy(hcd);
2986 err_create_buf:
2987 	usb_phy_roothub_power_off(hcd->phy_roothub);
2988 err_usb_phy_roothub_power_on:
2989 	usb_phy_roothub_exit(hcd->phy_roothub);
2990 
2991 	return retval;
2992 }
2993 EXPORT_SYMBOL_GPL(usb_add_hcd);
2994 
2995 /**
2996  * usb_remove_hcd - shutdown processing for generic HCDs
2997  * @hcd: the usb_hcd structure to remove
2998  *
2999  * Context: task context, might sleep.
3000  *
3001  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
3002  * invoking the HCD's stop() method.
3003  */
3004 void usb_remove_hcd(struct usb_hcd *hcd)
3005 {
3006 	struct usb_device *rhdev;
3007 	bool rh_registered;
3008 
3009 	if (!hcd) {
3010 		pr_debug("%s: hcd is NULL\n", __func__);
3011 		return;
3012 	}
3013 	rhdev = hcd->self.root_hub;
3014 
3015 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
3016 
3017 	usb_get_dev(rhdev);
3018 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
3019 	if (HC_IS_RUNNING (hcd->state))
3020 		hcd->state = HC_STATE_QUIESCING;
3021 
3022 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
3023 	spin_lock_irq (&hcd_root_hub_lock);
3024 	rh_registered = hcd->rh_registered;
3025 	hcd->rh_registered = 0;
3026 	spin_unlock_irq (&hcd_root_hub_lock);
3027 
3028 #ifdef CONFIG_PM
3029 	cancel_work_sync(&hcd->wakeup_work);
3030 #endif
3031 	cancel_work_sync(&hcd->died_work);
3032 
3033 	mutex_lock(&usb_bus_idr_lock);
3034 	if (rh_registered)
3035 		usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
3036 	mutex_unlock(&usb_bus_idr_lock);
3037 
3038 	/*
3039 	 * tasklet_kill() isn't needed here because:
3040 	 * - driver's disconnect() called from usb_disconnect() should
3041 	 *   make sure its URBs are completed during the disconnect()
3042 	 *   callback
3043 	 *
3044 	 * - it is too late to run complete() here since driver may have
3045 	 *   been removed already now
3046 	 */
3047 
3048 	/* Prevent any more root-hub status calls from the timer.
3049 	 * The HCD might still restart the timer (if a port status change
3050 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3051 	 * the hub_status_data() callback.
3052 	 */
3053 	usb_stop_hcd(hcd);
3054 
3055 	if (usb_hcd_is_primary_hcd(hcd)) {
3056 		if (hcd->irq > 0)
3057 			free_irq(hcd->irq, hcd);
3058 	}
3059 
3060 	usb_deregister_bus(&hcd->self);
3061 	hcd_buffer_destroy(hcd);
3062 
3063 	usb_phy_roothub_power_off(hcd->phy_roothub);
3064 	usb_phy_roothub_exit(hcd->phy_roothub);
3065 
3066 	usb_put_invalidate_rhdev(hcd);
3067 	hcd->flags = 0;
3068 }
3069 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3070 
3071 void
3072 usb_hcd_platform_shutdown(struct platform_device *dev)
3073 {
3074 	struct usb_hcd *hcd = platform_get_drvdata(dev);
3075 
3076 	/* No need for pm_runtime_put(), we're shutting down */
3077 	pm_runtime_get_sync(&dev->dev);
3078 
3079 	if (hcd->driver->shutdown)
3080 		hcd->driver->shutdown(hcd);
3081 }
3082 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3083 
3084 int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
3085 			    dma_addr_t dma, size_t size)
3086 {
3087 	int err;
3088 	void *local_mem;
3089 
3090 	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
3091 						  dev_to_node(hcd->self.sysdev),
3092 						  dev_name(hcd->self.sysdev));
3093 	if (IS_ERR(hcd->localmem_pool))
3094 		return PTR_ERR(hcd->localmem_pool);
3095 
3096 	/*
3097 	 * if a physical SRAM address was passed, map it, otherwise
3098 	 * allocate system memory as a buffer.
3099 	 */
3100 	if (phys_addr)
3101 		local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
3102 					  size, MEMREMAP_WC);
3103 	else
3104 		local_mem = dmam_alloc_attrs(hcd->self.sysdev, size, &dma,
3105 					     GFP_KERNEL,
3106 					     DMA_ATTR_WRITE_COMBINE);
3107 
3108 	if (IS_ERR_OR_NULL(local_mem)) {
3109 		if (!local_mem)
3110 			return -ENOMEM;
3111 
3112 		return PTR_ERR(local_mem);
3113 	}
3114 
3115 	/*
3116 	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
3117 	 * It's not backed by system memory and thus there's no kernel mapping
3118 	 * for it.
3119 	 */
3120 	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
3121 				dma, size, dev_to_node(hcd->self.sysdev));
3122 	if (err < 0) {
3123 		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
3124 			err);
3125 		return err;
3126 	}
3127 
3128 	return 0;
3129 }
3130 EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
3131 
3132 /*-------------------------------------------------------------------------*/
3133 
3134 #if IS_ENABLED(CONFIG_USB_MON)
3135 
3136 const struct usb_mon_operations *mon_ops;
3137 
3138 /*
3139  * The registration is unlocked.
3140  * We do it this way because we do not want to lock in hot paths.
3141  *
3142  * Notice that the code is minimally error-proof. Because usbmon needs
3143  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3144  */
3145 
3146 int usb_mon_register(const struct usb_mon_operations *ops)
3147 {
3148 
3149 	if (mon_ops)
3150 		return -EBUSY;
3151 
3152 	mon_ops = ops;
3153 	mb();
3154 	return 0;
3155 }
3156 EXPORT_SYMBOL_GPL (usb_mon_register);
3157 
3158 void usb_mon_deregister (void)
3159 {
3160 
3161 	if (mon_ops == NULL) {
3162 		printk(KERN_ERR "USB: monitor was not registered\n");
3163 		return;
3164 	}
3165 	mon_ops = NULL;
3166 	mb();
3167 }
3168 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3169 
3170 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3171