xref: /linux/drivers/usb/core/hcd.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * (C) Copyright Linus Torvalds 1999
3  * (C) Copyright Johannes Erdfelt 1999-2001
4  * (C) Copyright Andreas Gal 1999
5  * (C) Copyright Gregory P. Smith 1999
6  * (C) Copyright Deti Fliegl 1999
7  * (C) Copyright Randy Dunlap 2000
8  * (C) Copyright David Brownell 2000-2002
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License as published by the
12  * Free Software Foundation; either version 2 of the License, or (at your
13  * option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
18  * for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software Foundation,
22  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23  */
24 
25 #include <linux/bcd.h>
26 #include <linux/module.h>
27 #include <linux/version.h>
28 #include <linux/kernel.h>
29 #include <linux/slab.h>
30 #include <linux/completion.h>
31 #include <linux/utsname.h>
32 #include <linux/mm.h>
33 #include <asm/io.h>
34 #include <linux/device.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/mutex.h>
37 #include <asm/irq.h>
38 #include <asm/byteorder.h>
39 #include <asm/unaligned.h>
40 #include <linux/platform_device.h>
41 #include <linux/workqueue.h>
42 #include <linux/pm_runtime.h>
43 #include <linux/types.h>
44 
45 #include <linux/phy/phy.h>
46 #include <linux/usb.h>
47 #include <linux/usb/hcd.h>
48 #include <linux/usb/phy.h>
49 
50 #include "usb.h"
51 
52 
53 /*-------------------------------------------------------------------------*/
54 
55 /*
56  * USB Host Controller Driver framework
57  *
58  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
59  * HCD-specific behaviors/bugs.
60  *
61  * This does error checks, tracks devices and urbs, and delegates to a
62  * "hc_driver" only for code (and data) that really needs to know about
63  * hardware differences.  That includes root hub registers, i/o queues,
64  * and so on ... but as little else as possible.
65  *
66  * Shared code includes most of the "root hub" code (these are emulated,
67  * though each HC's hardware works differently) and PCI glue, plus request
68  * tracking overhead.  The HCD code should only block on spinlocks or on
69  * hardware handshaking; blocking on software events (such as other kernel
70  * threads releasing resources, or completing actions) is all generic.
71  *
72  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
73  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
74  * only by the hub driver ... and that neither should be seen or used by
75  * usb client device drivers.
76  *
77  * Contributors of ideas or unattributed patches include: David Brownell,
78  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
79  *
80  * HISTORY:
81  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
82  *		associated cleanup.  "usb_hcd" still != "usb_bus".
83  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
84  */
85 
86 /*-------------------------------------------------------------------------*/
87 
88 /* Keep track of which host controller drivers are loaded */
89 unsigned long usb_hcds_loaded;
90 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
91 
92 /* host controllers we manage */
93 LIST_HEAD (usb_bus_list);
94 EXPORT_SYMBOL_GPL (usb_bus_list);
95 
96 /* used when allocating bus numbers */
97 #define USB_MAXBUS		64
98 static DECLARE_BITMAP(busmap, USB_MAXBUS);
99 
100 /* used when updating list of hcds */
101 DEFINE_MUTEX(usb_bus_list_lock);	/* exported only for usbfs */
102 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
103 
104 /* used for controlling access to virtual root hubs */
105 static DEFINE_SPINLOCK(hcd_root_hub_lock);
106 
107 /* used when updating an endpoint's URB list */
108 static DEFINE_SPINLOCK(hcd_urb_list_lock);
109 
110 /* used to protect against unlinking URBs after the device is gone */
111 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
112 
113 /* wait queue for synchronous unlinks */
114 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
115 
116 static inline int is_root_hub(struct usb_device *udev)
117 {
118 	return (udev->parent == NULL);
119 }
120 
121 /*-------------------------------------------------------------------------*/
122 
123 /*
124  * Sharable chunks of root hub code.
125  */
126 
127 /*-------------------------------------------------------------------------*/
128 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
129 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
130 
131 /* usb 3.0 root hub device descriptor */
132 static const u8 usb3_rh_dev_descriptor[18] = {
133 	0x12,       /*  __u8  bLength; */
134 	0x01,       /*  __u8  bDescriptorType; Device */
135 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
136 
137 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
138 	0x00,	    /*  __u8  bDeviceSubClass; */
139 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
140 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
141 
142 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
143 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
144 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
145 
146 	0x03,       /*  __u8  iManufacturer; */
147 	0x02,       /*  __u8  iProduct; */
148 	0x01,       /*  __u8  iSerialNumber; */
149 	0x01        /*  __u8  bNumConfigurations; */
150 };
151 
152 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
153 static const u8 usb25_rh_dev_descriptor[18] = {
154 	0x12,       /*  __u8  bLength; */
155 	0x01,       /*  __u8  bDescriptorType; Device */
156 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
157 
158 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
159 	0x00,	    /*  __u8  bDeviceSubClass; */
160 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
161 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
162 
163 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
164 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
165 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
166 
167 	0x03,       /*  __u8  iManufacturer; */
168 	0x02,       /*  __u8  iProduct; */
169 	0x01,       /*  __u8  iSerialNumber; */
170 	0x01        /*  __u8  bNumConfigurations; */
171 };
172 
173 /* usb 2.0 root hub device descriptor */
174 static const u8 usb2_rh_dev_descriptor[18] = {
175 	0x12,       /*  __u8  bLength; */
176 	0x01,       /*  __u8  bDescriptorType; Device */
177 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
178 
179 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
180 	0x00,	    /*  __u8  bDeviceSubClass; */
181 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
182 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
183 
184 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
185 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
186 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
187 
188 	0x03,       /*  __u8  iManufacturer; */
189 	0x02,       /*  __u8  iProduct; */
190 	0x01,       /*  __u8  iSerialNumber; */
191 	0x01        /*  __u8  bNumConfigurations; */
192 };
193 
194 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
195 
196 /* usb 1.1 root hub device descriptor */
197 static const u8 usb11_rh_dev_descriptor[18] = {
198 	0x12,       /*  __u8  bLength; */
199 	0x01,       /*  __u8  bDescriptorType; Device */
200 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
201 
202 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
203 	0x00,	    /*  __u8  bDeviceSubClass; */
204 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
205 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
206 
207 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
208 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
209 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
210 
211 	0x03,       /*  __u8  iManufacturer; */
212 	0x02,       /*  __u8  iProduct; */
213 	0x01,       /*  __u8  iSerialNumber; */
214 	0x01        /*  __u8  bNumConfigurations; */
215 };
216 
217 
218 /*-------------------------------------------------------------------------*/
219 
220 /* Configuration descriptors for our root hubs */
221 
222 static const u8 fs_rh_config_descriptor[] = {
223 
224 	/* one configuration */
225 	0x09,       /*  __u8  bLength; */
226 	0x02,       /*  __u8  bDescriptorType; Configuration */
227 	0x19, 0x00, /*  __le16 wTotalLength; */
228 	0x01,       /*  __u8  bNumInterfaces; (1) */
229 	0x01,       /*  __u8  bConfigurationValue; */
230 	0x00,       /*  __u8  iConfiguration; */
231 	0xc0,       /*  __u8  bmAttributes;
232 				 Bit 7: must be set,
233 				     6: Self-powered,
234 				     5: Remote wakeup,
235 				     4..0: resvd */
236 	0x00,       /*  __u8  MaxPower; */
237 
238 	/* USB 1.1:
239 	 * USB 2.0, single TT organization (mandatory):
240 	 *	one interface, protocol 0
241 	 *
242 	 * USB 2.0, multiple TT organization (optional):
243 	 *	two interfaces, protocols 1 (like single TT)
244 	 *	and 2 (multiple TT mode) ... config is
245 	 *	sometimes settable
246 	 *	NOT IMPLEMENTED
247 	 */
248 
249 	/* one interface */
250 	0x09,       /*  __u8  if_bLength; */
251 	0x04,       /*  __u8  if_bDescriptorType; Interface */
252 	0x00,       /*  __u8  if_bInterfaceNumber; */
253 	0x00,       /*  __u8  if_bAlternateSetting; */
254 	0x01,       /*  __u8  if_bNumEndpoints; */
255 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
256 	0x00,       /*  __u8  if_bInterfaceSubClass; */
257 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
258 	0x00,       /*  __u8  if_iInterface; */
259 
260 	/* one endpoint (status change endpoint) */
261 	0x07,       /*  __u8  ep_bLength; */
262 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
263 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
264 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
265 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
266 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
267 };
268 
269 static const u8 hs_rh_config_descriptor[] = {
270 
271 	/* one configuration */
272 	0x09,       /*  __u8  bLength; */
273 	0x02,       /*  __u8  bDescriptorType; Configuration */
274 	0x19, 0x00, /*  __le16 wTotalLength; */
275 	0x01,       /*  __u8  bNumInterfaces; (1) */
276 	0x01,       /*  __u8  bConfigurationValue; */
277 	0x00,       /*  __u8  iConfiguration; */
278 	0xc0,       /*  __u8  bmAttributes;
279 				 Bit 7: must be set,
280 				     6: Self-powered,
281 				     5: Remote wakeup,
282 				     4..0: resvd */
283 	0x00,       /*  __u8  MaxPower; */
284 
285 	/* USB 1.1:
286 	 * USB 2.0, single TT organization (mandatory):
287 	 *	one interface, protocol 0
288 	 *
289 	 * USB 2.0, multiple TT organization (optional):
290 	 *	two interfaces, protocols 1 (like single TT)
291 	 *	and 2 (multiple TT mode) ... config is
292 	 *	sometimes settable
293 	 *	NOT IMPLEMENTED
294 	 */
295 
296 	/* one interface */
297 	0x09,       /*  __u8  if_bLength; */
298 	0x04,       /*  __u8  if_bDescriptorType; Interface */
299 	0x00,       /*  __u8  if_bInterfaceNumber; */
300 	0x00,       /*  __u8  if_bAlternateSetting; */
301 	0x01,       /*  __u8  if_bNumEndpoints; */
302 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
303 	0x00,       /*  __u8  if_bInterfaceSubClass; */
304 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
305 	0x00,       /*  __u8  if_iInterface; */
306 
307 	/* one endpoint (status change endpoint) */
308 	0x07,       /*  __u8  ep_bLength; */
309 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
310 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
311 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
312 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
313 		     * see hub.c:hub_configure() for details. */
314 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
315 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
316 };
317 
318 static const u8 ss_rh_config_descriptor[] = {
319 	/* one configuration */
320 	0x09,       /*  __u8  bLength; */
321 	0x02,       /*  __u8  bDescriptorType; Configuration */
322 	0x1f, 0x00, /*  __le16 wTotalLength; */
323 	0x01,       /*  __u8  bNumInterfaces; (1) */
324 	0x01,       /*  __u8  bConfigurationValue; */
325 	0x00,       /*  __u8  iConfiguration; */
326 	0xc0,       /*  __u8  bmAttributes;
327 				 Bit 7: must be set,
328 				     6: Self-powered,
329 				     5: Remote wakeup,
330 				     4..0: resvd */
331 	0x00,       /*  __u8  MaxPower; */
332 
333 	/* one interface */
334 	0x09,       /*  __u8  if_bLength; */
335 	0x04,       /*  __u8  if_bDescriptorType; Interface */
336 	0x00,       /*  __u8  if_bInterfaceNumber; */
337 	0x00,       /*  __u8  if_bAlternateSetting; */
338 	0x01,       /*  __u8  if_bNumEndpoints; */
339 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
340 	0x00,       /*  __u8  if_bInterfaceSubClass; */
341 	0x00,       /*  __u8  if_bInterfaceProtocol; */
342 	0x00,       /*  __u8  if_iInterface; */
343 
344 	/* one endpoint (status change endpoint) */
345 	0x07,       /*  __u8  ep_bLength; */
346 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
347 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
348 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
349 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
350 		     * see hub.c:hub_configure() for details. */
351 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
352 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
353 
354 	/* one SuperSpeed endpoint companion descriptor */
355 	0x06,        /* __u8 ss_bLength */
356 	0x30,        /* __u8 ss_bDescriptorType; SuperSpeed EP Companion */
357 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
358 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
359 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
360 };
361 
362 /* authorized_default behaviour:
363  * -1 is authorized for all devices except wireless (old behaviour)
364  * 0 is unauthorized for all devices
365  * 1 is authorized for all devices
366  */
367 static int authorized_default = -1;
368 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
369 MODULE_PARM_DESC(authorized_default,
370 		"Default USB device authorization: 0 is not authorized, 1 is "
371 		"authorized, -1 is authorized except for wireless USB (default, "
372 		"old behaviour");
373 /*-------------------------------------------------------------------------*/
374 
375 /**
376  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
377  * @s: Null-terminated ASCII (actually ISO-8859-1) string
378  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
379  * @len: Length (in bytes; may be odd) of descriptor buffer.
380  *
381  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
382  * whichever is less.
383  *
384  * Note:
385  * USB String descriptors can contain at most 126 characters; input
386  * strings longer than that are truncated.
387  */
388 static unsigned
389 ascii2desc(char const *s, u8 *buf, unsigned len)
390 {
391 	unsigned n, t = 2 + 2*strlen(s);
392 
393 	if (t > 254)
394 		t = 254;	/* Longest possible UTF string descriptor */
395 	if (len > t)
396 		len = t;
397 
398 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
399 
400 	n = len;
401 	while (n--) {
402 		*buf++ = t;
403 		if (!n--)
404 			break;
405 		*buf++ = t >> 8;
406 		t = (unsigned char)*s++;
407 	}
408 	return len;
409 }
410 
411 /**
412  * rh_string() - provides string descriptors for root hub
413  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
414  * @hcd: the host controller for this root hub
415  * @data: buffer for output packet
416  * @len: length of the provided buffer
417  *
418  * Produces either a manufacturer, product or serial number string for the
419  * virtual root hub device.
420  *
421  * Return: The number of bytes filled in: the length of the descriptor or
422  * of the provided buffer, whichever is less.
423  */
424 static unsigned
425 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
426 {
427 	char buf[100];
428 	char const *s;
429 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
430 
431 	/* language ids */
432 	switch (id) {
433 	case 0:
434 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
435 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
436 		if (len > 4)
437 			len = 4;
438 		memcpy(data, langids, len);
439 		return len;
440 	case 1:
441 		/* Serial number */
442 		s = hcd->self.bus_name;
443 		break;
444 	case 2:
445 		/* Product name */
446 		s = hcd->product_desc;
447 		break;
448 	case 3:
449 		/* Manufacturer */
450 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
451 			init_utsname()->release, hcd->driver->description);
452 		s = buf;
453 		break;
454 	default:
455 		/* Can't happen; caller guarantees it */
456 		return 0;
457 	}
458 
459 	return ascii2desc(s, data, len);
460 }
461 
462 
463 /* Root hub control transfers execute synchronously */
464 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
465 {
466 	struct usb_ctrlrequest *cmd;
467 	u16		typeReq, wValue, wIndex, wLength;
468 	u8		*ubuf = urb->transfer_buffer;
469 	unsigned	len = 0;
470 	int		status;
471 	u8		patch_wakeup = 0;
472 	u8		patch_protocol = 0;
473 	u16		tbuf_size;
474 	u8		*tbuf = NULL;
475 	const u8	*bufp;
476 
477 	might_sleep();
478 
479 	spin_lock_irq(&hcd_root_hub_lock);
480 	status = usb_hcd_link_urb_to_ep(hcd, urb);
481 	spin_unlock_irq(&hcd_root_hub_lock);
482 	if (status)
483 		return status;
484 	urb->hcpriv = hcd;	/* Indicate it's queued */
485 
486 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
487 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
488 	wValue   = le16_to_cpu (cmd->wValue);
489 	wIndex   = le16_to_cpu (cmd->wIndex);
490 	wLength  = le16_to_cpu (cmd->wLength);
491 
492 	if (wLength > urb->transfer_buffer_length)
493 		goto error;
494 
495 	/*
496 	 * tbuf should be at least as big as the
497 	 * USB hub descriptor.
498 	 */
499 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
500 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
501 	if (!tbuf)
502 		return -ENOMEM;
503 
504 	bufp = tbuf;
505 
506 
507 	urb->actual_length = 0;
508 	switch (typeReq) {
509 
510 	/* DEVICE REQUESTS */
511 
512 	/* The root hub's remote wakeup enable bit is implemented using
513 	 * driver model wakeup flags.  If this system supports wakeup
514 	 * through USB, userspace may change the default "allow wakeup"
515 	 * policy through sysfs or these calls.
516 	 *
517 	 * Most root hubs support wakeup from downstream devices, for
518 	 * runtime power management (disabling USB clocks and reducing
519 	 * VBUS power usage).  However, not all of them do so; silicon,
520 	 * board, and BIOS bugs here are not uncommon, so these can't
521 	 * be treated quite like external hubs.
522 	 *
523 	 * Likewise, not all root hubs will pass wakeup events upstream,
524 	 * to wake up the whole system.  So don't assume root hub and
525 	 * controller capabilities are identical.
526 	 */
527 
528 	case DeviceRequest | USB_REQ_GET_STATUS:
529 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
530 					<< USB_DEVICE_REMOTE_WAKEUP)
531 				| (1 << USB_DEVICE_SELF_POWERED);
532 		tbuf[1] = 0;
533 		len = 2;
534 		break;
535 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
536 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
537 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
538 		else
539 			goto error;
540 		break;
541 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
542 		if (device_can_wakeup(&hcd->self.root_hub->dev)
543 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
544 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
545 		else
546 			goto error;
547 		break;
548 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
549 		tbuf[0] = 1;
550 		len = 1;
551 			/* FALLTHROUGH */
552 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
553 		break;
554 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
555 		switch (wValue & 0xff00) {
556 		case USB_DT_DEVICE << 8:
557 			switch (hcd->speed) {
558 			case HCD_USB3:
559 				bufp = usb3_rh_dev_descriptor;
560 				break;
561 			case HCD_USB25:
562 				bufp = usb25_rh_dev_descriptor;
563 				break;
564 			case HCD_USB2:
565 				bufp = usb2_rh_dev_descriptor;
566 				break;
567 			case HCD_USB11:
568 				bufp = usb11_rh_dev_descriptor;
569 				break;
570 			default:
571 				goto error;
572 			}
573 			len = 18;
574 			if (hcd->has_tt)
575 				patch_protocol = 1;
576 			break;
577 		case USB_DT_CONFIG << 8:
578 			switch (hcd->speed) {
579 			case HCD_USB3:
580 				bufp = ss_rh_config_descriptor;
581 				len = sizeof ss_rh_config_descriptor;
582 				break;
583 			case HCD_USB25:
584 			case HCD_USB2:
585 				bufp = hs_rh_config_descriptor;
586 				len = sizeof hs_rh_config_descriptor;
587 				break;
588 			case HCD_USB11:
589 				bufp = fs_rh_config_descriptor;
590 				len = sizeof fs_rh_config_descriptor;
591 				break;
592 			default:
593 				goto error;
594 			}
595 			if (device_can_wakeup(&hcd->self.root_hub->dev))
596 				patch_wakeup = 1;
597 			break;
598 		case USB_DT_STRING << 8:
599 			if ((wValue & 0xff) < 4)
600 				urb->actual_length = rh_string(wValue & 0xff,
601 						hcd, ubuf, wLength);
602 			else /* unsupported IDs --> "protocol stall" */
603 				goto error;
604 			break;
605 		case USB_DT_BOS << 8:
606 			goto nongeneric;
607 		default:
608 			goto error;
609 		}
610 		break;
611 	case DeviceRequest | USB_REQ_GET_INTERFACE:
612 		tbuf[0] = 0;
613 		len = 1;
614 			/* FALLTHROUGH */
615 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
616 		break;
617 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
618 		/* wValue == urb->dev->devaddr */
619 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
620 			wValue);
621 		break;
622 
623 	/* INTERFACE REQUESTS (no defined feature/status flags) */
624 
625 	/* ENDPOINT REQUESTS */
626 
627 	case EndpointRequest | USB_REQ_GET_STATUS:
628 		/* ENDPOINT_HALT flag */
629 		tbuf[0] = 0;
630 		tbuf[1] = 0;
631 		len = 2;
632 			/* FALLTHROUGH */
633 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
634 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
635 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
636 		break;
637 
638 	/* CLASS REQUESTS (and errors) */
639 
640 	default:
641 nongeneric:
642 		/* non-generic request */
643 		switch (typeReq) {
644 		case GetHubStatus:
645 		case GetPortStatus:
646 			len = 4;
647 			break;
648 		case GetHubDescriptor:
649 			len = sizeof (struct usb_hub_descriptor);
650 			break;
651 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
652 			/* len is returned by hub_control */
653 			break;
654 		}
655 		status = hcd->driver->hub_control (hcd,
656 			typeReq, wValue, wIndex,
657 			tbuf, wLength);
658 
659 		if (typeReq == GetHubDescriptor)
660 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
661 				(struct usb_hub_descriptor *)tbuf);
662 		break;
663 error:
664 		/* "protocol stall" on error */
665 		status = -EPIPE;
666 	}
667 
668 	if (status < 0) {
669 		len = 0;
670 		if (status != -EPIPE) {
671 			dev_dbg (hcd->self.controller,
672 				"CTRL: TypeReq=0x%x val=0x%x "
673 				"idx=0x%x len=%d ==> %d\n",
674 				typeReq, wValue, wIndex,
675 				wLength, status);
676 		}
677 	} else if (status > 0) {
678 		/* hub_control may return the length of data copied. */
679 		len = status;
680 		status = 0;
681 	}
682 	if (len) {
683 		if (urb->transfer_buffer_length < len)
684 			len = urb->transfer_buffer_length;
685 		urb->actual_length = len;
686 		/* always USB_DIR_IN, toward host */
687 		memcpy (ubuf, bufp, len);
688 
689 		/* report whether RH hardware supports remote wakeup */
690 		if (patch_wakeup &&
691 				len > offsetof (struct usb_config_descriptor,
692 						bmAttributes))
693 			((struct usb_config_descriptor *)ubuf)->bmAttributes
694 				|= USB_CONFIG_ATT_WAKEUP;
695 
696 		/* report whether RH hardware has an integrated TT */
697 		if (patch_protocol &&
698 				len > offsetof(struct usb_device_descriptor,
699 						bDeviceProtocol))
700 			((struct usb_device_descriptor *) ubuf)->
701 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
702 	}
703 
704 	kfree(tbuf);
705 
706 	/* any errors get returned through the urb completion */
707 	spin_lock_irq(&hcd_root_hub_lock);
708 	usb_hcd_unlink_urb_from_ep(hcd, urb);
709 	usb_hcd_giveback_urb(hcd, urb, status);
710 	spin_unlock_irq(&hcd_root_hub_lock);
711 	return 0;
712 }
713 
714 /*-------------------------------------------------------------------------*/
715 
716 /*
717  * Root Hub interrupt transfers are polled using a timer if the
718  * driver requests it; otherwise the driver is responsible for
719  * calling usb_hcd_poll_rh_status() when an event occurs.
720  *
721  * Completions are called in_interrupt(), but they may or may not
722  * be in_irq().
723  */
724 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
725 {
726 	struct urb	*urb;
727 	int		length;
728 	unsigned long	flags;
729 	char		buffer[6];	/* Any root hubs with > 31 ports? */
730 
731 	if (unlikely(!hcd->rh_pollable))
732 		return;
733 	if (!hcd->uses_new_polling && !hcd->status_urb)
734 		return;
735 
736 	length = hcd->driver->hub_status_data(hcd, buffer);
737 	if (length > 0) {
738 
739 		/* try to complete the status urb */
740 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
741 		urb = hcd->status_urb;
742 		if (urb) {
743 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
744 			hcd->status_urb = NULL;
745 			urb->actual_length = length;
746 			memcpy(urb->transfer_buffer, buffer, length);
747 
748 			usb_hcd_unlink_urb_from_ep(hcd, urb);
749 			usb_hcd_giveback_urb(hcd, urb, 0);
750 		} else {
751 			length = 0;
752 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
753 		}
754 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
755 	}
756 
757 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
758 	 * exceed that limit if HZ is 100. The math is more clunky than
759 	 * maybe expected, this is to make sure that all timers for USB devices
760 	 * fire at the same time to give the CPU a break in between */
761 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
762 			(length == 0 && hcd->status_urb != NULL))
763 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
764 }
765 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
766 
767 /* timer callback */
768 static void rh_timer_func (unsigned long _hcd)
769 {
770 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
771 }
772 
773 /*-------------------------------------------------------------------------*/
774 
775 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
776 {
777 	int		retval;
778 	unsigned long	flags;
779 	unsigned	len = 1 + (urb->dev->maxchild / 8);
780 
781 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
782 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
783 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
784 		retval = -EINVAL;
785 		goto done;
786 	}
787 
788 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
789 	if (retval)
790 		goto done;
791 
792 	hcd->status_urb = urb;
793 	urb->hcpriv = hcd;	/* indicate it's queued */
794 	if (!hcd->uses_new_polling)
795 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
796 
797 	/* If a status change has already occurred, report it ASAP */
798 	else if (HCD_POLL_PENDING(hcd))
799 		mod_timer(&hcd->rh_timer, jiffies);
800 	retval = 0;
801  done:
802 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
803 	return retval;
804 }
805 
806 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
807 {
808 	if (usb_endpoint_xfer_int(&urb->ep->desc))
809 		return rh_queue_status (hcd, urb);
810 	if (usb_endpoint_xfer_control(&urb->ep->desc))
811 		return rh_call_control (hcd, urb);
812 	return -EINVAL;
813 }
814 
815 /*-------------------------------------------------------------------------*/
816 
817 /* Unlinks of root-hub control URBs are legal, but they don't do anything
818  * since these URBs always execute synchronously.
819  */
820 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
821 {
822 	unsigned long	flags;
823 	int		rc;
824 
825 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
826 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
827 	if (rc)
828 		goto done;
829 
830 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
831 		;	/* Do nothing */
832 
833 	} else {				/* Status URB */
834 		if (!hcd->uses_new_polling)
835 			del_timer (&hcd->rh_timer);
836 		if (urb == hcd->status_urb) {
837 			hcd->status_urb = NULL;
838 			usb_hcd_unlink_urb_from_ep(hcd, urb);
839 			usb_hcd_giveback_urb(hcd, urb, status);
840 		}
841 	}
842  done:
843 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
844 	return rc;
845 }
846 
847 
848 
849 /*
850  * Show & store the current value of authorized_default
851  */
852 static ssize_t authorized_default_show(struct device *dev,
853 				       struct device_attribute *attr, char *buf)
854 {
855 	struct usb_device *rh_usb_dev = to_usb_device(dev);
856 	struct usb_bus *usb_bus = rh_usb_dev->bus;
857 	struct usb_hcd *usb_hcd;
858 
859 	usb_hcd = bus_to_hcd(usb_bus);
860 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
861 }
862 
863 static ssize_t authorized_default_store(struct device *dev,
864 					struct device_attribute *attr,
865 					const char *buf, size_t size)
866 {
867 	ssize_t result;
868 	unsigned val;
869 	struct usb_device *rh_usb_dev = to_usb_device(dev);
870 	struct usb_bus *usb_bus = rh_usb_dev->bus;
871 	struct usb_hcd *usb_hcd;
872 
873 	usb_hcd = bus_to_hcd(usb_bus);
874 	result = sscanf(buf, "%u\n", &val);
875 	if (result == 1) {
876 		usb_hcd->authorized_default = val ? 1 : 0;
877 		result = size;
878 	} else {
879 		result = -EINVAL;
880 	}
881 	return result;
882 }
883 static DEVICE_ATTR_RW(authorized_default);
884 
885 /* Group all the USB bus attributes */
886 static struct attribute *usb_bus_attrs[] = {
887 		&dev_attr_authorized_default.attr,
888 		NULL,
889 };
890 
891 static struct attribute_group usb_bus_attr_group = {
892 	.name = NULL,	/* we want them in the same directory */
893 	.attrs = usb_bus_attrs,
894 };
895 
896 
897 
898 /*-------------------------------------------------------------------------*/
899 
900 /**
901  * usb_bus_init - shared initialization code
902  * @bus: the bus structure being initialized
903  *
904  * This code is used to initialize a usb_bus structure, memory for which is
905  * separately managed.
906  */
907 static void usb_bus_init (struct usb_bus *bus)
908 {
909 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
910 
911 	bus->devnum_next = 1;
912 
913 	bus->root_hub = NULL;
914 	bus->busnum = -1;
915 	bus->bandwidth_allocated = 0;
916 	bus->bandwidth_int_reqs  = 0;
917 	bus->bandwidth_isoc_reqs = 0;
918 	mutex_init(&bus->usb_address0_mutex);
919 
920 	INIT_LIST_HEAD (&bus->bus_list);
921 }
922 
923 /*-------------------------------------------------------------------------*/
924 
925 /**
926  * usb_register_bus - registers the USB host controller with the usb core
927  * @bus: pointer to the bus to register
928  * Context: !in_interrupt()
929  *
930  * Assigns a bus number, and links the controller into usbcore data
931  * structures so that it can be seen by scanning the bus list.
932  *
933  * Return: 0 if successful. A negative error code otherwise.
934  */
935 static int usb_register_bus(struct usb_bus *bus)
936 {
937 	int result = -E2BIG;
938 	int busnum;
939 
940 	mutex_lock(&usb_bus_list_lock);
941 	busnum = find_next_zero_bit(busmap, USB_MAXBUS, 1);
942 	if (busnum >= USB_MAXBUS) {
943 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
944 		goto error_find_busnum;
945 	}
946 	set_bit(busnum, busmap);
947 	bus->busnum = busnum;
948 
949 	/* Add it to the local list of buses */
950 	list_add (&bus->bus_list, &usb_bus_list);
951 	mutex_unlock(&usb_bus_list_lock);
952 
953 	usb_notify_add_bus(bus);
954 
955 	dev_info (bus->controller, "new USB bus registered, assigned bus "
956 		  "number %d\n", bus->busnum);
957 	return 0;
958 
959 error_find_busnum:
960 	mutex_unlock(&usb_bus_list_lock);
961 	return result;
962 }
963 
964 /**
965  * usb_deregister_bus - deregisters the USB host controller
966  * @bus: pointer to the bus to deregister
967  * Context: !in_interrupt()
968  *
969  * Recycles the bus number, and unlinks the controller from usbcore data
970  * structures so that it won't be seen by scanning the bus list.
971  */
972 static void usb_deregister_bus (struct usb_bus *bus)
973 {
974 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
975 
976 	/*
977 	 * NOTE: make sure that all the devices are removed by the
978 	 * controller code, as well as having it call this when cleaning
979 	 * itself up
980 	 */
981 	mutex_lock(&usb_bus_list_lock);
982 	list_del (&bus->bus_list);
983 	mutex_unlock(&usb_bus_list_lock);
984 
985 	usb_notify_remove_bus(bus);
986 
987 	clear_bit(bus->busnum, busmap);
988 }
989 
990 /**
991  * register_root_hub - called by usb_add_hcd() to register a root hub
992  * @hcd: host controller for this root hub
993  *
994  * This function registers the root hub with the USB subsystem.  It sets up
995  * the device properly in the device tree and then calls usb_new_device()
996  * to register the usb device.  It also assigns the root hub's USB address
997  * (always 1).
998  *
999  * Return: 0 if successful. A negative error code otherwise.
1000  */
1001 static int register_root_hub(struct usb_hcd *hcd)
1002 {
1003 	struct device *parent_dev = hcd->self.controller;
1004 	struct usb_device *usb_dev = hcd->self.root_hub;
1005 	const int devnum = 1;
1006 	int retval;
1007 
1008 	usb_dev->devnum = devnum;
1009 	usb_dev->bus->devnum_next = devnum + 1;
1010 	memset (&usb_dev->bus->devmap.devicemap, 0,
1011 			sizeof usb_dev->bus->devmap.devicemap);
1012 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1013 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1014 
1015 	mutex_lock(&usb_bus_list_lock);
1016 
1017 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1018 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1019 	if (retval != sizeof usb_dev->descriptor) {
1020 		mutex_unlock(&usb_bus_list_lock);
1021 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1022 				dev_name(&usb_dev->dev), retval);
1023 		return (retval < 0) ? retval : -EMSGSIZE;
1024 	}
1025 
1026 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1027 		retval = usb_get_bos_descriptor(usb_dev);
1028 		if (!retval) {
1029 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1030 		} else if (usb_dev->speed == USB_SPEED_SUPER) {
1031 			mutex_unlock(&usb_bus_list_lock);
1032 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1033 					dev_name(&usb_dev->dev), retval);
1034 			return retval;
1035 		}
1036 	}
1037 
1038 	retval = usb_new_device (usb_dev);
1039 	if (retval) {
1040 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1041 				dev_name(&usb_dev->dev), retval);
1042 	} else {
1043 		spin_lock_irq (&hcd_root_hub_lock);
1044 		hcd->rh_registered = 1;
1045 		spin_unlock_irq (&hcd_root_hub_lock);
1046 
1047 		/* Did the HC die before the root hub was registered? */
1048 		if (HCD_DEAD(hcd))
1049 			usb_hc_died (hcd);	/* This time clean up */
1050 	}
1051 	mutex_unlock(&usb_bus_list_lock);
1052 
1053 	return retval;
1054 }
1055 
1056 /*
1057  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1058  * @bus: the bus which the root hub belongs to
1059  * @portnum: the port which is being resumed
1060  *
1061  * HCDs should call this function when they know that a resume signal is
1062  * being sent to a root-hub port.  The root hub will be prevented from
1063  * going into autosuspend until usb_hcd_end_port_resume() is called.
1064  *
1065  * The bus's private lock must be held by the caller.
1066  */
1067 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1068 {
1069 	unsigned bit = 1 << portnum;
1070 
1071 	if (!(bus->resuming_ports & bit)) {
1072 		bus->resuming_ports |= bit;
1073 		pm_runtime_get_noresume(&bus->root_hub->dev);
1074 	}
1075 }
1076 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1077 
1078 /*
1079  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1080  * @bus: the bus which the root hub belongs to
1081  * @portnum: the port which is being resumed
1082  *
1083  * HCDs should call this function when they know that a resume signal has
1084  * stopped being sent to a root-hub port.  The root hub will be allowed to
1085  * autosuspend again.
1086  *
1087  * The bus's private lock must be held by the caller.
1088  */
1089 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1090 {
1091 	unsigned bit = 1 << portnum;
1092 
1093 	if (bus->resuming_ports & bit) {
1094 		bus->resuming_ports &= ~bit;
1095 		pm_runtime_put_noidle(&bus->root_hub->dev);
1096 	}
1097 }
1098 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1099 
1100 /*-------------------------------------------------------------------------*/
1101 
1102 /**
1103  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1104  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1105  * @is_input: true iff the transaction sends data to the host
1106  * @isoc: true for isochronous transactions, false for interrupt ones
1107  * @bytecount: how many bytes in the transaction.
1108  *
1109  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1110  *
1111  * Note:
1112  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1113  * scheduled in software, this function is only used for such scheduling.
1114  */
1115 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1116 {
1117 	unsigned long	tmp;
1118 
1119 	switch (speed) {
1120 	case USB_SPEED_LOW: 	/* INTR only */
1121 		if (is_input) {
1122 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1123 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1124 		} else {
1125 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1126 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1127 		}
1128 	case USB_SPEED_FULL:	/* ISOC or INTR */
1129 		if (isoc) {
1130 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1131 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1132 		} else {
1133 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1134 			return 9107L + BW_HOST_DELAY + tmp;
1135 		}
1136 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1137 		/* FIXME adjust for input vs output */
1138 		if (isoc)
1139 			tmp = HS_NSECS_ISO (bytecount);
1140 		else
1141 			tmp = HS_NSECS (bytecount);
1142 		return tmp;
1143 	default:
1144 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1145 		return -1;
1146 	}
1147 }
1148 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1149 
1150 
1151 /*-------------------------------------------------------------------------*/
1152 
1153 /*
1154  * Generic HC operations.
1155  */
1156 
1157 /*-------------------------------------------------------------------------*/
1158 
1159 /**
1160  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1161  * @hcd: host controller to which @urb was submitted
1162  * @urb: URB being submitted
1163  *
1164  * Host controller drivers should call this routine in their enqueue()
1165  * method.  The HCD's private spinlock must be held and interrupts must
1166  * be disabled.  The actions carried out here are required for URB
1167  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1168  *
1169  * Return: 0 for no error, otherwise a negative error code (in which case
1170  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1171  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1172  * the private spinlock and returning.
1173  */
1174 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1175 {
1176 	int		rc = 0;
1177 
1178 	spin_lock(&hcd_urb_list_lock);
1179 
1180 	/* Check that the URB isn't being killed */
1181 	if (unlikely(atomic_read(&urb->reject))) {
1182 		rc = -EPERM;
1183 		goto done;
1184 	}
1185 
1186 	if (unlikely(!urb->ep->enabled)) {
1187 		rc = -ENOENT;
1188 		goto done;
1189 	}
1190 
1191 	if (unlikely(!urb->dev->can_submit)) {
1192 		rc = -EHOSTUNREACH;
1193 		goto done;
1194 	}
1195 
1196 	/*
1197 	 * Check the host controller's state and add the URB to the
1198 	 * endpoint's queue.
1199 	 */
1200 	if (HCD_RH_RUNNING(hcd)) {
1201 		urb->unlinked = 0;
1202 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1203 	} else {
1204 		rc = -ESHUTDOWN;
1205 		goto done;
1206 	}
1207  done:
1208 	spin_unlock(&hcd_urb_list_lock);
1209 	return rc;
1210 }
1211 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1212 
1213 /**
1214  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1215  * @hcd: host controller to which @urb was submitted
1216  * @urb: URB being checked for unlinkability
1217  * @status: error code to store in @urb if the unlink succeeds
1218  *
1219  * Host controller drivers should call this routine in their dequeue()
1220  * method.  The HCD's private spinlock must be held and interrupts must
1221  * be disabled.  The actions carried out here are required for making
1222  * sure than an unlink is valid.
1223  *
1224  * Return: 0 for no error, otherwise a negative error code (in which case
1225  * the dequeue() method must fail).  The possible error codes are:
1226  *
1227  *	-EIDRM: @urb was not submitted or has already completed.
1228  *		The completion function may not have been called yet.
1229  *
1230  *	-EBUSY: @urb has already been unlinked.
1231  */
1232 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1233 		int status)
1234 {
1235 	struct list_head	*tmp;
1236 
1237 	/* insist the urb is still queued */
1238 	list_for_each(tmp, &urb->ep->urb_list) {
1239 		if (tmp == &urb->urb_list)
1240 			break;
1241 	}
1242 	if (tmp != &urb->urb_list)
1243 		return -EIDRM;
1244 
1245 	/* Any status except -EINPROGRESS means something already started to
1246 	 * unlink this URB from the hardware.  So there's no more work to do.
1247 	 */
1248 	if (urb->unlinked)
1249 		return -EBUSY;
1250 	urb->unlinked = status;
1251 	return 0;
1252 }
1253 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1254 
1255 /**
1256  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1257  * @hcd: host controller to which @urb was submitted
1258  * @urb: URB being unlinked
1259  *
1260  * Host controller drivers should call this routine before calling
1261  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1262  * interrupts must be disabled.  The actions carried out here are required
1263  * for URB completion.
1264  */
1265 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1266 {
1267 	/* clear all state linking urb to this dev (and hcd) */
1268 	spin_lock(&hcd_urb_list_lock);
1269 	list_del_init(&urb->urb_list);
1270 	spin_unlock(&hcd_urb_list_lock);
1271 }
1272 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1273 
1274 /*
1275  * Some usb host controllers can only perform dma using a small SRAM area.
1276  * The usb core itself is however optimized for host controllers that can dma
1277  * using regular system memory - like pci devices doing bus mastering.
1278  *
1279  * To support host controllers with limited dma capabilities we provide dma
1280  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1281  * For this to work properly the host controller code must first use the
1282  * function dma_declare_coherent_memory() to point out which memory area
1283  * that should be used for dma allocations.
1284  *
1285  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1286  * dma using dma_alloc_coherent() which in turn allocates from the memory
1287  * area pointed out with dma_declare_coherent_memory().
1288  *
1289  * So, to summarize...
1290  *
1291  * - We need "local" memory, canonical example being
1292  *   a small SRAM on a discrete controller being the
1293  *   only memory that the controller can read ...
1294  *   (a) "normal" kernel memory is no good, and
1295  *   (b) there's not enough to share
1296  *
1297  * - The only *portable* hook for such stuff in the
1298  *   DMA framework is dma_declare_coherent_memory()
1299  *
1300  * - So we use that, even though the primary requirement
1301  *   is that the memory be "local" (hence addressable
1302  *   by that device), not "coherent".
1303  *
1304  */
1305 
1306 static int hcd_alloc_coherent(struct usb_bus *bus,
1307 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1308 			      void **vaddr_handle, size_t size,
1309 			      enum dma_data_direction dir)
1310 {
1311 	unsigned char *vaddr;
1312 
1313 	if (*vaddr_handle == NULL) {
1314 		WARN_ON_ONCE(1);
1315 		return -EFAULT;
1316 	}
1317 
1318 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1319 				 mem_flags, dma_handle);
1320 	if (!vaddr)
1321 		return -ENOMEM;
1322 
1323 	/*
1324 	 * Store the virtual address of the buffer at the end
1325 	 * of the allocated dma buffer. The size of the buffer
1326 	 * may be uneven so use unaligned functions instead
1327 	 * of just rounding up. It makes sense to optimize for
1328 	 * memory footprint over access speed since the amount
1329 	 * of memory available for dma may be limited.
1330 	 */
1331 	put_unaligned((unsigned long)*vaddr_handle,
1332 		      (unsigned long *)(vaddr + size));
1333 
1334 	if (dir == DMA_TO_DEVICE)
1335 		memcpy(vaddr, *vaddr_handle, size);
1336 
1337 	*vaddr_handle = vaddr;
1338 	return 0;
1339 }
1340 
1341 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1342 			      void **vaddr_handle, size_t size,
1343 			      enum dma_data_direction dir)
1344 {
1345 	unsigned char *vaddr = *vaddr_handle;
1346 
1347 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1348 
1349 	if (dir == DMA_FROM_DEVICE)
1350 		memcpy(vaddr, *vaddr_handle, size);
1351 
1352 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1353 
1354 	*vaddr_handle = vaddr;
1355 	*dma_handle = 0;
1356 }
1357 
1358 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1359 {
1360 	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1361 		dma_unmap_single(hcd->self.controller,
1362 				urb->setup_dma,
1363 				sizeof(struct usb_ctrlrequest),
1364 				DMA_TO_DEVICE);
1365 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1366 		hcd_free_coherent(urb->dev->bus,
1367 				&urb->setup_dma,
1368 				(void **) &urb->setup_packet,
1369 				sizeof(struct usb_ctrlrequest),
1370 				DMA_TO_DEVICE);
1371 
1372 	/* Make it safe to call this routine more than once */
1373 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1374 }
1375 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1376 
1377 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1378 {
1379 	if (hcd->driver->unmap_urb_for_dma)
1380 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1381 	else
1382 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1383 }
1384 
1385 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1386 {
1387 	enum dma_data_direction dir;
1388 
1389 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1390 
1391 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1392 	if (urb->transfer_flags & URB_DMA_MAP_SG)
1393 		dma_unmap_sg(hcd->self.controller,
1394 				urb->sg,
1395 				urb->num_sgs,
1396 				dir);
1397 	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1398 		dma_unmap_page(hcd->self.controller,
1399 				urb->transfer_dma,
1400 				urb->transfer_buffer_length,
1401 				dir);
1402 	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1403 		dma_unmap_single(hcd->self.controller,
1404 				urb->transfer_dma,
1405 				urb->transfer_buffer_length,
1406 				dir);
1407 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1408 		hcd_free_coherent(urb->dev->bus,
1409 				&urb->transfer_dma,
1410 				&urb->transfer_buffer,
1411 				urb->transfer_buffer_length,
1412 				dir);
1413 
1414 	/* Make it safe to call this routine more than once */
1415 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1416 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1417 }
1418 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1419 
1420 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1421 			   gfp_t mem_flags)
1422 {
1423 	if (hcd->driver->map_urb_for_dma)
1424 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1425 	else
1426 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1427 }
1428 
1429 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1430 			    gfp_t mem_flags)
1431 {
1432 	enum dma_data_direction dir;
1433 	int ret = 0;
1434 
1435 	/* Map the URB's buffers for DMA access.
1436 	 * Lower level HCD code should use *_dma exclusively,
1437 	 * unless it uses pio or talks to another transport,
1438 	 * or uses the provided scatter gather list for bulk.
1439 	 */
1440 
1441 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1442 		if (hcd->self.uses_pio_for_control)
1443 			return ret;
1444 		if (hcd->self.uses_dma) {
1445 			urb->setup_dma = dma_map_single(
1446 					hcd->self.controller,
1447 					urb->setup_packet,
1448 					sizeof(struct usb_ctrlrequest),
1449 					DMA_TO_DEVICE);
1450 			if (dma_mapping_error(hcd->self.controller,
1451 						urb->setup_dma))
1452 				return -EAGAIN;
1453 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1454 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1455 			ret = hcd_alloc_coherent(
1456 					urb->dev->bus, mem_flags,
1457 					&urb->setup_dma,
1458 					(void **)&urb->setup_packet,
1459 					sizeof(struct usb_ctrlrequest),
1460 					DMA_TO_DEVICE);
1461 			if (ret)
1462 				return ret;
1463 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1464 		}
1465 	}
1466 
1467 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1468 	if (urb->transfer_buffer_length != 0
1469 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1470 		if (hcd->self.uses_dma) {
1471 			if (urb->num_sgs) {
1472 				int n;
1473 
1474 				/* We don't support sg for isoc transfers ! */
1475 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1476 					WARN_ON(1);
1477 					return -EINVAL;
1478 				}
1479 
1480 				n = dma_map_sg(
1481 						hcd->self.controller,
1482 						urb->sg,
1483 						urb->num_sgs,
1484 						dir);
1485 				if (n <= 0)
1486 					ret = -EAGAIN;
1487 				else
1488 					urb->transfer_flags |= URB_DMA_MAP_SG;
1489 				urb->num_mapped_sgs = n;
1490 				if (n != urb->num_sgs)
1491 					urb->transfer_flags |=
1492 							URB_DMA_SG_COMBINED;
1493 			} else if (urb->sg) {
1494 				struct scatterlist *sg = urb->sg;
1495 				urb->transfer_dma = dma_map_page(
1496 						hcd->self.controller,
1497 						sg_page(sg),
1498 						sg->offset,
1499 						urb->transfer_buffer_length,
1500 						dir);
1501 				if (dma_mapping_error(hcd->self.controller,
1502 						urb->transfer_dma))
1503 					ret = -EAGAIN;
1504 				else
1505 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1506 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1507 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1508 				ret = -EAGAIN;
1509 			} else {
1510 				urb->transfer_dma = dma_map_single(
1511 						hcd->self.controller,
1512 						urb->transfer_buffer,
1513 						urb->transfer_buffer_length,
1514 						dir);
1515 				if (dma_mapping_error(hcd->self.controller,
1516 						urb->transfer_dma))
1517 					ret = -EAGAIN;
1518 				else
1519 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1520 			}
1521 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1522 			ret = hcd_alloc_coherent(
1523 					urb->dev->bus, mem_flags,
1524 					&urb->transfer_dma,
1525 					&urb->transfer_buffer,
1526 					urb->transfer_buffer_length,
1527 					dir);
1528 			if (ret == 0)
1529 				urb->transfer_flags |= URB_MAP_LOCAL;
1530 		}
1531 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1532 				URB_SETUP_MAP_LOCAL)))
1533 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1534 	}
1535 	return ret;
1536 }
1537 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1538 
1539 /*-------------------------------------------------------------------------*/
1540 
1541 /* may be called in any context with a valid urb->dev usecount
1542  * caller surrenders "ownership" of urb
1543  * expects usb_submit_urb() to have sanity checked and conditioned all
1544  * inputs in the urb
1545  */
1546 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1547 {
1548 	int			status;
1549 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1550 
1551 	/* increment urb's reference count as part of giving it to the HCD
1552 	 * (which will control it).  HCD guarantees that it either returns
1553 	 * an error or calls giveback(), but not both.
1554 	 */
1555 	usb_get_urb(urb);
1556 	atomic_inc(&urb->use_count);
1557 	atomic_inc(&urb->dev->urbnum);
1558 	usbmon_urb_submit(&hcd->self, urb);
1559 
1560 	/* NOTE requirements on root-hub callers (usbfs and the hub
1561 	 * driver, for now):  URBs' urb->transfer_buffer must be
1562 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1563 	 * they could clobber root hub response data.  Also, control
1564 	 * URBs must be submitted in process context with interrupts
1565 	 * enabled.
1566 	 */
1567 
1568 	if (is_root_hub(urb->dev)) {
1569 		status = rh_urb_enqueue(hcd, urb);
1570 	} else {
1571 		status = map_urb_for_dma(hcd, urb, mem_flags);
1572 		if (likely(status == 0)) {
1573 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1574 			if (unlikely(status))
1575 				unmap_urb_for_dma(hcd, urb);
1576 		}
1577 	}
1578 
1579 	if (unlikely(status)) {
1580 		usbmon_urb_submit_error(&hcd->self, urb, status);
1581 		urb->hcpriv = NULL;
1582 		INIT_LIST_HEAD(&urb->urb_list);
1583 		atomic_dec(&urb->use_count);
1584 		atomic_dec(&urb->dev->urbnum);
1585 		if (atomic_read(&urb->reject))
1586 			wake_up(&usb_kill_urb_queue);
1587 		usb_put_urb(urb);
1588 	}
1589 	return status;
1590 }
1591 
1592 /*-------------------------------------------------------------------------*/
1593 
1594 /* this makes the hcd giveback() the urb more quickly, by kicking it
1595  * off hardware queues (which may take a while) and returning it as
1596  * soon as practical.  we've already set up the urb's return status,
1597  * but we can't know if the callback completed already.
1598  */
1599 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1600 {
1601 	int		value;
1602 
1603 	if (is_root_hub(urb->dev))
1604 		value = usb_rh_urb_dequeue(hcd, urb, status);
1605 	else {
1606 
1607 		/* The only reason an HCD might fail this call is if
1608 		 * it has not yet fully queued the urb to begin with.
1609 		 * Such failures should be harmless. */
1610 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1611 	}
1612 	return value;
1613 }
1614 
1615 /*
1616  * called in any context
1617  *
1618  * caller guarantees urb won't be recycled till both unlink()
1619  * and the urb's completion function return
1620  */
1621 int usb_hcd_unlink_urb (struct urb *urb, int status)
1622 {
1623 	struct usb_hcd		*hcd;
1624 	struct usb_device	*udev = urb->dev;
1625 	int			retval = -EIDRM;
1626 	unsigned long		flags;
1627 
1628 	/* Prevent the device and bus from going away while
1629 	 * the unlink is carried out.  If they are already gone
1630 	 * then urb->use_count must be 0, since disconnected
1631 	 * devices can't have any active URBs.
1632 	 */
1633 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1634 	if (atomic_read(&urb->use_count) > 0) {
1635 		retval = 0;
1636 		usb_get_dev(udev);
1637 	}
1638 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1639 	if (retval == 0) {
1640 		hcd = bus_to_hcd(urb->dev->bus);
1641 		retval = unlink1(hcd, urb, status);
1642 		if (retval == 0)
1643 			retval = -EINPROGRESS;
1644 		else if (retval != -EIDRM && retval != -EBUSY)
1645 			dev_dbg(&udev->dev, "hcd_unlink_urb %p fail %d\n",
1646 					urb, retval);
1647 		usb_put_dev(udev);
1648 	}
1649 	return retval;
1650 }
1651 
1652 /*-------------------------------------------------------------------------*/
1653 
1654 static void __usb_hcd_giveback_urb(struct urb *urb)
1655 {
1656 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1657 	struct usb_anchor *anchor = urb->anchor;
1658 	int status = urb->unlinked;
1659 	unsigned long flags;
1660 
1661 	urb->hcpriv = NULL;
1662 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1663 	    urb->actual_length < urb->transfer_buffer_length &&
1664 	    !status))
1665 		status = -EREMOTEIO;
1666 
1667 	unmap_urb_for_dma(hcd, urb);
1668 	usbmon_urb_complete(&hcd->self, urb, status);
1669 	usb_anchor_suspend_wakeups(anchor);
1670 	usb_unanchor_urb(urb);
1671 	if (likely(status == 0))
1672 		usb_led_activity(USB_LED_EVENT_HOST);
1673 
1674 	/* pass ownership to the completion handler */
1675 	urb->status = status;
1676 
1677 	/*
1678 	 * We disable local IRQs here avoid possible deadlock because
1679 	 * drivers may call spin_lock() to hold lock which might be
1680 	 * acquired in one hard interrupt handler.
1681 	 *
1682 	 * The local_irq_save()/local_irq_restore() around complete()
1683 	 * will be removed if current USB drivers have been cleaned up
1684 	 * and no one may trigger the above deadlock situation when
1685 	 * running complete() in tasklet.
1686 	 */
1687 	local_irq_save(flags);
1688 	urb->complete(urb);
1689 	local_irq_restore(flags);
1690 
1691 	usb_anchor_resume_wakeups(anchor);
1692 	atomic_dec(&urb->use_count);
1693 	if (unlikely(atomic_read(&urb->reject)))
1694 		wake_up(&usb_kill_urb_queue);
1695 	usb_put_urb(urb);
1696 }
1697 
1698 static void usb_giveback_urb_bh(unsigned long param)
1699 {
1700 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1701 	struct list_head local_list;
1702 
1703 	spin_lock_irq(&bh->lock);
1704 	bh->running = true;
1705  restart:
1706 	list_replace_init(&bh->head, &local_list);
1707 	spin_unlock_irq(&bh->lock);
1708 
1709 	while (!list_empty(&local_list)) {
1710 		struct urb *urb;
1711 
1712 		urb = list_entry(local_list.next, struct urb, urb_list);
1713 		list_del_init(&urb->urb_list);
1714 		bh->completing_ep = urb->ep;
1715 		__usb_hcd_giveback_urb(urb);
1716 		bh->completing_ep = NULL;
1717 	}
1718 
1719 	/* check if there are new URBs to giveback */
1720 	spin_lock_irq(&bh->lock);
1721 	if (!list_empty(&bh->head))
1722 		goto restart;
1723 	bh->running = false;
1724 	spin_unlock_irq(&bh->lock);
1725 }
1726 
1727 /**
1728  * usb_hcd_giveback_urb - return URB from HCD to device driver
1729  * @hcd: host controller returning the URB
1730  * @urb: urb being returned to the USB device driver.
1731  * @status: completion status code for the URB.
1732  * Context: in_interrupt()
1733  *
1734  * This hands the URB from HCD to its USB device driver, using its
1735  * completion function.  The HCD has freed all per-urb resources
1736  * (and is done using urb->hcpriv).  It also released all HCD locks;
1737  * the device driver won't cause problems if it frees, modifies,
1738  * or resubmits this URB.
1739  *
1740  * If @urb was unlinked, the value of @status will be overridden by
1741  * @urb->unlinked.  Erroneous short transfers are detected in case
1742  * the HCD hasn't checked for them.
1743  */
1744 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1745 {
1746 	struct giveback_urb_bh *bh;
1747 	bool running, high_prio_bh;
1748 
1749 	/* pass status to tasklet via unlinked */
1750 	if (likely(!urb->unlinked))
1751 		urb->unlinked = status;
1752 
1753 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1754 		__usb_hcd_giveback_urb(urb);
1755 		return;
1756 	}
1757 
1758 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1759 		bh = &hcd->high_prio_bh;
1760 		high_prio_bh = true;
1761 	} else {
1762 		bh = &hcd->low_prio_bh;
1763 		high_prio_bh = false;
1764 	}
1765 
1766 	spin_lock(&bh->lock);
1767 	list_add_tail(&urb->urb_list, &bh->head);
1768 	running = bh->running;
1769 	spin_unlock(&bh->lock);
1770 
1771 	if (running)
1772 		;
1773 	else if (high_prio_bh)
1774 		tasklet_hi_schedule(&bh->bh);
1775 	else
1776 		tasklet_schedule(&bh->bh);
1777 }
1778 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1779 
1780 /*-------------------------------------------------------------------------*/
1781 
1782 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1783  * queue to drain completely.  The caller must first insure that no more
1784  * URBs can be submitted for this endpoint.
1785  */
1786 void usb_hcd_flush_endpoint(struct usb_device *udev,
1787 		struct usb_host_endpoint *ep)
1788 {
1789 	struct usb_hcd		*hcd;
1790 	struct urb		*urb;
1791 
1792 	if (!ep)
1793 		return;
1794 	might_sleep();
1795 	hcd = bus_to_hcd(udev->bus);
1796 
1797 	/* No more submits can occur */
1798 	spin_lock_irq(&hcd_urb_list_lock);
1799 rescan:
1800 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1801 		int	is_in;
1802 
1803 		if (urb->unlinked)
1804 			continue;
1805 		usb_get_urb (urb);
1806 		is_in = usb_urb_dir_in(urb);
1807 		spin_unlock(&hcd_urb_list_lock);
1808 
1809 		/* kick hcd */
1810 		unlink1(hcd, urb, -ESHUTDOWN);
1811 		dev_dbg (hcd->self.controller,
1812 			"shutdown urb %p ep%d%s%s\n",
1813 			urb, usb_endpoint_num(&ep->desc),
1814 			is_in ? "in" : "out",
1815 			({	char *s;
1816 
1817 				 switch (usb_endpoint_type(&ep->desc)) {
1818 				 case USB_ENDPOINT_XFER_CONTROL:
1819 					s = ""; break;
1820 				 case USB_ENDPOINT_XFER_BULK:
1821 					s = "-bulk"; break;
1822 				 case USB_ENDPOINT_XFER_INT:
1823 					s = "-intr"; break;
1824 				 default:
1825 					s = "-iso"; break;
1826 				};
1827 				s;
1828 			}));
1829 		usb_put_urb (urb);
1830 
1831 		/* list contents may have changed */
1832 		spin_lock(&hcd_urb_list_lock);
1833 		goto rescan;
1834 	}
1835 	spin_unlock_irq(&hcd_urb_list_lock);
1836 
1837 	/* Wait until the endpoint queue is completely empty */
1838 	while (!list_empty (&ep->urb_list)) {
1839 		spin_lock_irq(&hcd_urb_list_lock);
1840 
1841 		/* The list may have changed while we acquired the spinlock */
1842 		urb = NULL;
1843 		if (!list_empty (&ep->urb_list)) {
1844 			urb = list_entry (ep->urb_list.prev, struct urb,
1845 					urb_list);
1846 			usb_get_urb (urb);
1847 		}
1848 		spin_unlock_irq(&hcd_urb_list_lock);
1849 
1850 		if (urb) {
1851 			usb_kill_urb (urb);
1852 			usb_put_urb (urb);
1853 		}
1854 	}
1855 }
1856 
1857 /**
1858  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1859  *				the bus bandwidth
1860  * @udev: target &usb_device
1861  * @new_config: new configuration to install
1862  * @cur_alt: the current alternate interface setting
1863  * @new_alt: alternate interface setting that is being installed
1864  *
1865  * To change configurations, pass in the new configuration in new_config,
1866  * and pass NULL for cur_alt and new_alt.
1867  *
1868  * To reset a device's configuration (put the device in the ADDRESSED state),
1869  * pass in NULL for new_config, cur_alt, and new_alt.
1870  *
1871  * To change alternate interface settings, pass in NULL for new_config,
1872  * pass in the current alternate interface setting in cur_alt,
1873  * and pass in the new alternate interface setting in new_alt.
1874  *
1875  * Return: An error if the requested bandwidth change exceeds the
1876  * bus bandwidth or host controller internal resources.
1877  */
1878 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1879 		struct usb_host_config *new_config,
1880 		struct usb_host_interface *cur_alt,
1881 		struct usb_host_interface *new_alt)
1882 {
1883 	int num_intfs, i, j;
1884 	struct usb_host_interface *alt = NULL;
1885 	int ret = 0;
1886 	struct usb_hcd *hcd;
1887 	struct usb_host_endpoint *ep;
1888 
1889 	hcd = bus_to_hcd(udev->bus);
1890 	if (!hcd->driver->check_bandwidth)
1891 		return 0;
1892 
1893 	/* Configuration is being removed - set configuration 0 */
1894 	if (!new_config && !cur_alt) {
1895 		for (i = 1; i < 16; ++i) {
1896 			ep = udev->ep_out[i];
1897 			if (ep)
1898 				hcd->driver->drop_endpoint(hcd, udev, ep);
1899 			ep = udev->ep_in[i];
1900 			if (ep)
1901 				hcd->driver->drop_endpoint(hcd, udev, ep);
1902 		}
1903 		hcd->driver->check_bandwidth(hcd, udev);
1904 		return 0;
1905 	}
1906 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1907 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1908 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1909 	 * ok to exclude it.
1910 	 */
1911 	if (new_config) {
1912 		num_intfs = new_config->desc.bNumInterfaces;
1913 		/* Remove endpoints (except endpoint 0, which is always on the
1914 		 * schedule) from the old config from the schedule
1915 		 */
1916 		for (i = 1; i < 16; ++i) {
1917 			ep = udev->ep_out[i];
1918 			if (ep) {
1919 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1920 				if (ret < 0)
1921 					goto reset;
1922 			}
1923 			ep = udev->ep_in[i];
1924 			if (ep) {
1925 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1926 				if (ret < 0)
1927 					goto reset;
1928 			}
1929 		}
1930 		for (i = 0; i < num_intfs; ++i) {
1931 			struct usb_host_interface *first_alt;
1932 			int iface_num;
1933 
1934 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1935 			iface_num = first_alt->desc.bInterfaceNumber;
1936 			/* Set up endpoints for alternate interface setting 0 */
1937 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1938 			if (!alt)
1939 				/* No alt setting 0? Pick the first setting. */
1940 				alt = first_alt;
1941 
1942 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1943 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1944 				if (ret < 0)
1945 					goto reset;
1946 			}
1947 		}
1948 	}
1949 	if (cur_alt && new_alt) {
1950 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1951 				cur_alt->desc.bInterfaceNumber);
1952 
1953 		if (!iface)
1954 			return -EINVAL;
1955 		if (iface->resetting_device) {
1956 			/*
1957 			 * The USB core just reset the device, so the xHCI host
1958 			 * and the device will think alt setting 0 is installed.
1959 			 * However, the USB core will pass in the alternate
1960 			 * setting installed before the reset as cur_alt.  Dig
1961 			 * out the alternate setting 0 structure, or the first
1962 			 * alternate setting if a broken device doesn't have alt
1963 			 * setting 0.
1964 			 */
1965 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1966 			if (!cur_alt)
1967 				cur_alt = &iface->altsetting[0];
1968 		}
1969 
1970 		/* Drop all the endpoints in the current alt setting */
1971 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1972 			ret = hcd->driver->drop_endpoint(hcd, udev,
1973 					&cur_alt->endpoint[i]);
1974 			if (ret < 0)
1975 				goto reset;
1976 		}
1977 		/* Add all the endpoints in the new alt setting */
1978 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1979 			ret = hcd->driver->add_endpoint(hcd, udev,
1980 					&new_alt->endpoint[i]);
1981 			if (ret < 0)
1982 				goto reset;
1983 		}
1984 	}
1985 	ret = hcd->driver->check_bandwidth(hcd, udev);
1986 reset:
1987 	if (ret < 0)
1988 		hcd->driver->reset_bandwidth(hcd, udev);
1989 	return ret;
1990 }
1991 
1992 /* Disables the endpoint: synchronizes with the hcd to make sure all
1993  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1994  * have been called previously.  Use for set_configuration, set_interface,
1995  * driver removal, physical disconnect.
1996  *
1997  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1998  * type, maxpacket size, toggle, halt status, and scheduling.
1999  */
2000 void usb_hcd_disable_endpoint(struct usb_device *udev,
2001 		struct usb_host_endpoint *ep)
2002 {
2003 	struct usb_hcd		*hcd;
2004 
2005 	might_sleep();
2006 	hcd = bus_to_hcd(udev->bus);
2007 	if (hcd->driver->endpoint_disable)
2008 		hcd->driver->endpoint_disable(hcd, ep);
2009 }
2010 
2011 /**
2012  * usb_hcd_reset_endpoint - reset host endpoint state
2013  * @udev: USB device.
2014  * @ep:   the endpoint to reset.
2015  *
2016  * Resets any host endpoint state such as the toggle bit, sequence
2017  * number and current window.
2018  */
2019 void usb_hcd_reset_endpoint(struct usb_device *udev,
2020 			    struct usb_host_endpoint *ep)
2021 {
2022 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2023 
2024 	if (hcd->driver->endpoint_reset)
2025 		hcd->driver->endpoint_reset(hcd, ep);
2026 	else {
2027 		int epnum = usb_endpoint_num(&ep->desc);
2028 		int is_out = usb_endpoint_dir_out(&ep->desc);
2029 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2030 
2031 		usb_settoggle(udev, epnum, is_out, 0);
2032 		if (is_control)
2033 			usb_settoggle(udev, epnum, !is_out, 0);
2034 	}
2035 }
2036 
2037 /**
2038  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2039  * @interface:		alternate setting that includes all endpoints.
2040  * @eps:		array of endpoints that need streams.
2041  * @num_eps:		number of endpoints in the array.
2042  * @num_streams:	number of streams to allocate.
2043  * @mem_flags:		flags hcd should use to allocate memory.
2044  *
2045  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2046  * Drivers may queue multiple transfers to different stream IDs, which may
2047  * complete in a different order than they were queued.
2048  *
2049  * Return: On success, the number of allocated streams. On failure, a negative
2050  * error code.
2051  */
2052 int usb_alloc_streams(struct usb_interface *interface,
2053 		struct usb_host_endpoint **eps, unsigned int num_eps,
2054 		unsigned int num_streams, gfp_t mem_flags)
2055 {
2056 	struct usb_hcd *hcd;
2057 	struct usb_device *dev;
2058 	int i, ret;
2059 
2060 	dev = interface_to_usbdev(interface);
2061 	hcd = bus_to_hcd(dev->bus);
2062 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2063 		return -EINVAL;
2064 	if (dev->speed != USB_SPEED_SUPER)
2065 		return -EINVAL;
2066 	if (dev->state < USB_STATE_CONFIGURED)
2067 		return -ENODEV;
2068 
2069 	for (i = 0; i < num_eps; i++) {
2070 		/* Streams only apply to bulk endpoints. */
2071 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2072 			return -EINVAL;
2073 		/* Re-alloc is not allowed */
2074 		if (eps[i]->streams)
2075 			return -EINVAL;
2076 	}
2077 
2078 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2079 			num_streams, mem_flags);
2080 	if (ret < 0)
2081 		return ret;
2082 
2083 	for (i = 0; i < num_eps; i++)
2084 		eps[i]->streams = ret;
2085 
2086 	return ret;
2087 }
2088 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2089 
2090 /**
2091  * usb_free_streams - free bulk endpoint stream IDs.
2092  * @interface:	alternate setting that includes all endpoints.
2093  * @eps:	array of endpoints to remove streams from.
2094  * @num_eps:	number of endpoints in the array.
2095  * @mem_flags:	flags hcd should use to allocate memory.
2096  *
2097  * Reverts a group of bulk endpoints back to not using stream IDs.
2098  * Can fail if we are given bad arguments, or HCD is broken.
2099  *
2100  * Return: 0 on success. On failure, a negative error code.
2101  */
2102 int usb_free_streams(struct usb_interface *interface,
2103 		struct usb_host_endpoint **eps, unsigned int num_eps,
2104 		gfp_t mem_flags)
2105 {
2106 	struct usb_hcd *hcd;
2107 	struct usb_device *dev;
2108 	int i, ret;
2109 
2110 	dev = interface_to_usbdev(interface);
2111 	hcd = bus_to_hcd(dev->bus);
2112 	if (dev->speed != USB_SPEED_SUPER)
2113 		return -EINVAL;
2114 
2115 	/* Double-free is not allowed */
2116 	for (i = 0; i < num_eps; i++)
2117 		if (!eps[i] || !eps[i]->streams)
2118 			return -EINVAL;
2119 
2120 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2121 	if (ret < 0)
2122 		return ret;
2123 
2124 	for (i = 0; i < num_eps; i++)
2125 		eps[i]->streams = 0;
2126 
2127 	return ret;
2128 }
2129 EXPORT_SYMBOL_GPL(usb_free_streams);
2130 
2131 /* Protect against drivers that try to unlink URBs after the device
2132  * is gone, by waiting until all unlinks for @udev are finished.
2133  * Since we don't currently track URBs by device, simply wait until
2134  * nothing is running in the locked region of usb_hcd_unlink_urb().
2135  */
2136 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2137 {
2138 	spin_lock_irq(&hcd_urb_unlink_lock);
2139 	spin_unlock_irq(&hcd_urb_unlink_lock);
2140 }
2141 
2142 /*-------------------------------------------------------------------------*/
2143 
2144 /* called in any context */
2145 int usb_hcd_get_frame_number (struct usb_device *udev)
2146 {
2147 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2148 
2149 	if (!HCD_RH_RUNNING(hcd))
2150 		return -ESHUTDOWN;
2151 	return hcd->driver->get_frame_number (hcd);
2152 }
2153 
2154 /*-------------------------------------------------------------------------*/
2155 
2156 #ifdef	CONFIG_PM
2157 
2158 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2159 {
2160 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2161 	int		status;
2162 	int		old_state = hcd->state;
2163 
2164 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2165 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2166 			rhdev->do_remote_wakeup);
2167 	if (HCD_DEAD(hcd)) {
2168 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2169 		return 0;
2170 	}
2171 
2172 	if (!hcd->driver->bus_suspend) {
2173 		status = -ENOENT;
2174 	} else {
2175 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2176 		hcd->state = HC_STATE_QUIESCING;
2177 		status = hcd->driver->bus_suspend(hcd);
2178 	}
2179 	if (status == 0) {
2180 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2181 		hcd->state = HC_STATE_SUSPENDED;
2182 
2183 		/* Did we race with a root-hub wakeup event? */
2184 		if (rhdev->do_remote_wakeup) {
2185 			char	buffer[6];
2186 
2187 			status = hcd->driver->hub_status_data(hcd, buffer);
2188 			if (status != 0) {
2189 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2190 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2191 				status = -EBUSY;
2192 			}
2193 		}
2194 	} else {
2195 		spin_lock_irq(&hcd_root_hub_lock);
2196 		if (!HCD_DEAD(hcd)) {
2197 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2198 			hcd->state = old_state;
2199 		}
2200 		spin_unlock_irq(&hcd_root_hub_lock);
2201 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2202 				"suspend", status);
2203 	}
2204 	return status;
2205 }
2206 
2207 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2208 {
2209 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2210 	int		status;
2211 	int		old_state = hcd->state;
2212 
2213 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2214 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2215 	if (HCD_DEAD(hcd)) {
2216 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2217 		return 0;
2218 	}
2219 	if (!hcd->driver->bus_resume)
2220 		return -ENOENT;
2221 	if (HCD_RH_RUNNING(hcd))
2222 		return 0;
2223 
2224 	hcd->state = HC_STATE_RESUMING;
2225 	status = hcd->driver->bus_resume(hcd);
2226 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2227 	if (status == 0) {
2228 		struct usb_device *udev;
2229 		int port1;
2230 
2231 		spin_lock_irq(&hcd_root_hub_lock);
2232 		if (!HCD_DEAD(hcd)) {
2233 			usb_set_device_state(rhdev, rhdev->actconfig
2234 					? USB_STATE_CONFIGURED
2235 					: USB_STATE_ADDRESS);
2236 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2237 			hcd->state = HC_STATE_RUNNING;
2238 		}
2239 		spin_unlock_irq(&hcd_root_hub_lock);
2240 
2241 		/*
2242 		 * Check whether any of the enabled ports on the root hub are
2243 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2244 		 * (this is what the USB-2 spec calls a "global resume").
2245 		 * Otherwise we can skip the delay.
2246 		 */
2247 		usb_hub_for_each_child(rhdev, port1, udev) {
2248 			if (udev->state != USB_STATE_NOTATTACHED &&
2249 					!udev->port_is_suspended) {
2250 				usleep_range(10000, 11000);	/* TRSMRCY */
2251 				break;
2252 			}
2253 		}
2254 	} else {
2255 		hcd->state = old_state;
2256 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2257 				"resume", status);
2258 		if (status != -ESHUTDOWN)
2259 			usb_hc_died(hcd);
2260 	}
2261 	return status;
2262 }
2263 
2264 /* Workqueue routine for root-hub remote wakeup */
2265 static void hcd_resume_work(struct work_struct *work)
2266 {
2267 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2268 	struct usb_device *udev = hcd->self.root_hub;
2269 
2270 	usb_remote_wakeup(udev);
2271 }
2272 
2273 /**
2274  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2275  * @hcd: host controller for this root hub
2276  *
2277  * The USB host controller calls this function when its root hub is
2278  * suspended (with the remote wakeup feature enabled) and a remote
2279  * wakeup request is received.  The routine submits a workqueue request
2280  * to resume the root hub (that is, manage its downstream ports again).
2281  */
2282 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2283 {
2284 	unsigned long flags;
2285 
2286 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2287 	if (hcd->rh_registered) {
2288 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2289 		queue_work(pm_wq, &hcd->wakeup_work);
2290 	}
2291 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2292 }
2293 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2294 
2295 #endif	/* CONFIG_PM */
2296 
2297 /*-------------------------------------------------------------------------*/
2298 
2299 #ifdef	CONFIG_USB_OTG
2300 
2301 /**
2302  * usb_bus_start_enum - start immediate enumeration (for OTG)
2303  * @bus: the bus (must use hcd framework)
2304  * @port_num: 1-based number of port; usually bus->otg_port
2305  * Context: in_interrupt()
2306  *
2307  * Starts enumeration, with an immediate reset followed later by
2308  * hub_wq identifying and possibly configuring the device.
2309  * This is needed by OTG controller drivers, where it helps meet
2310  * HNP protocol timing requirements for starting a port reset.
2311  *
2312  * Return: 0 if successful.
2313  */
2314 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2315 {
2316 	struct usb_hcd		*hcd;
2317 	int			status = -EOPNOTSUPP;
2318 
2319 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2320 	 * boards with root hubs hooked up to internal devices (instead of
2321 	 * just the OTG port) may need more attention to resetting...
2322 	 */
2323 	hcd = container_of (bus, struct usb_hcd, self);
2324 	if (port_num && hcd->driver->start_port_reset)
2325 		status = hcd->driver->start_port_reset(hcd, port_num);
2326 
2327 	/* allocate hub_wq shortly after (first) root port reset finishes;
2328 	 * it may issue others, until at least 50 msecs have passed.
2329 	 */
2330 	if (status == 0)
2331 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2332 	return status;
2333 }
2334 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2335 
2336 #endif
2337 
2338 /*-------------------------------------------------------------------------*/
2339 
2340 /**
2341  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2342  * @irq: the IRQ being raised
2343  * @__hcd: pointer to the HCD whose IRQ is being signaled
2344  *
2345  * If the controller isn't HALTed, calls the driver's irq handler.
2346  * Checks whether the controller is now dead.
2347  *
2348  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2349  */
2350 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2351 {
2352 	struct usb_hcd		*hcd = __hcd;
2353 	irqreturn_t		rc;
2354 
2355 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2356 		rc = IRQ_NONE;
2357 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2358 		rc = IRQ_NONE;
2359 	else
2360 		rc = IRQ_HANDLED;
2361 
2362 	return rc;
2363 }
2364 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2365 
2366 /*-------------------------------------------------------------------------*/
2367 
2368 /**
2369  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2370  * @hcd: pointer to the HCD representing the controller
2371  *
2372  * This is called by bus glue to report a USB host controller that died
2373  * while operations may still have been pending.  It's called automatically
2374  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2375  *
2376  * Only call this function with the primary HCD.
2377  */
2378 void usb_hc_died (struct usb_hcd *hcd)
2379 {
2380 	unsigned long flags;
2381 
2382 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2383 
2384 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2385 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2386 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2387 	if (hcd->rh_registered) {
2388 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2389 
2390 		/* make hub_wq clean up old urbs and devices */
2391 		usb_set_device_state (hcd->self.root_hub,
2392 				USB_STATE_NOTATTACHED);
2393 		usb_kick_hub_wq(hcd->self.root_hub);
2394 	}
2395 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2396 		hcd = hcd->shared_hcd;
2397 		if (hcd->rh_registered) {
2398 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2399 
2400 			/* make hub_wq clean up old urbs and devices */
2401 			usb_set_device_state(hcd->self.root_hub,
2402 					USB_STATE_NOTATTACHED);
2403 			usb_kick_hub_wq(hcd->self.root_hub);
2404 		}
2405 	}
2406 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2407 	/* Make sure that the other roothub is also deallocated. */
2408 }
2409 EXPORT_SYMBOL_GPL (usb_hc_died);
2410 
2411 /*-------------------------------------------------------------------------*/
2412 
2413 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2414 {
2415 
2416 	spin_lock_init(&bh->lock);
2417 	INIT_LIST_HEAD(&bh->head);
2418 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2419 }
2420 
2421 /**
2422  * usb_create_shared_hcd - create and initialize an HCD structure
2423  * @driver: HC driver that will use this hcd
2424  * @dev: device for this HC, stored in hcd->self.controller
2425  * @bus_name: value to store in hcd->self.bus_name
2426  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2427  *              PCI device.  Only allocate certain resources for the primary HCD
2428  * Context: !in_interrupt()
2429  *
2430  * Allocate a struct usb_hcd, with extra space at the end for the
2431  * HC driver's private data.  Initialize the generic members of the
2432  * hcd structure.
2433  *
2434  * Return: On success, a pointer to the created and initialized HCD structure.
2435  * On failure (e.g. if memory is unavailable), %NULL.
2436  */
2437 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2438 		struct device *dev, const char *bus_name,
2439 		struct usb_hcd *primary_hcd)
2440 {
2441 	struct usb_hcd *hcd;
2442 
2443 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2444 	if (!hcd) {
2445 		dev_dbg (dev, "hcd alloc failed\n");
2446 		return NULL;
2447 	}
2448 	if (primary_hcd == NULL) {
2449 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2450 				GFP_KERNEL);
2451 		if (!hcd->bandwidth_mutex) {
2452 			kfree(hcd);
2453 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2454 			return NULL;
2455 		}
2456 		mutex_init(hcd->bandwidth_mutex);
2457 		dev_set_drvdata(dev, hcd);
2458 	} else {
2459 		mutex_lock(&usb_port_peer_mutex);
2460 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2461 		hcd->primary_hcd = primary_hcd;
2462 		primary_hcd->primary_hcd = primary_hcd;
2463 		hcd->shared_hcd = primary_hcd;
2464 		primary_hcd->shared_hcd = hcd;
2465 		mutex_unlock(&usb_port_peer_mutex);
2466 	}
2467 
2468 	kref_init(&hcd->kref);
2469 
2470 	usb_bus_init(&hcd->self);
2471 	hcd->self.controller = dev;
2472 	hcd->self.bus_name = bus_name;
2473 	hcd->self.uses_dma = (dev->dma_mask != NULL);
2474 
2475 	init_timer(&hcd->rh_timer);
2476 	hcd->rh_timer.function = rh_timer_func;
2477 	hcd->rh_timer.data = (unsigned long) hcd;
2478 #ifdef CONFIG_PM
2479 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2480 #endif
2481 
2482 	hcd->driver = driver;
2483 	hcd->speed = driver->flags & HCD_MASK;
2484 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2485 			"USB Host Controller";
2486 	return hcd;
2487 }
2488 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2489 
2490 /**
2491  * usb_create_hcd - create and initialize an HCD structure
2492  * @driver: HC driver that will use this hcd
2493  * @dev: device for this HC, stored in hcd->self.controller
2494  * @bus_name: value to store in hcd->self.bus_name
2495  * Context: !in_interrupt()
2496  *
2497  * Allocate a struct usb_hcd, with extra space at the end for the
2498  * HC driver's private data.  Initialize the generic members of the
2499  * hcd structure.
2500  *
2501  * Return: On success, a pointer to the created and initialized HCD
2502  * structure. On failure (e.g. if memory is unavailable), %NULL.
2503  */
2504 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2505 		struct device *dev, const char *bus_name)
2506 {
2507 	return usb_create_shared_hcd(driver, dev, bus_name, NULL);
2508 }
2509 EXPORT_SYMBOL_GPL(usb_create_hcd);
2510 
2511 /*
2512  * Roothubs that share one PCI device must also share the bandwidth mutex.
2513  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2514  * deallocated.
2515  *
2516  * Make sure to only deallocate the bandwidth_mutex when the primary HCD is
2517  * freed.  When hcd_release() is called for either hcd in a peer set
2518  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers to
2519  * block new peering attempts
2520  */
2521 static void hcd_release(struct kref *kref)
2522 {
2523 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2524 
2525 	mutex_lock(&usb_port_peer_mutex);
2526 	if (usb_hcd_is_primary_hcd(hcd))
2527 		kfree(hcd->bandwidth_mutex);
2528 	if (hcd->shared_hcd) {
2529 		struct usb_hcd *peer = hcd->shared_hcd;
2530 
2531 		peer->shared_hcd = NULL;
2532 		if (peer->primary_hcd == hcd)
2533 			peer->primary_hcd = NULL;
2534 	}
2535 	mutex_unlock(&usb_port_peer_mutex);
2536 	kfree(hcd);
2537 }
2538 
2539 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2540 {
2541 	if (hcd)
2542 		kref_get (&hcd->kref);
2543 	return hcd;
2544 }
2545 EXPORT_SYMBOL_GPL(usb_get_hcd);
2546 
2547 void usb_put_hcd (struct usb_hcd *hcd)
2548 {
2549 	if (hcd)
2550 		kref_put (&hcd->kref, hcd_release);
2551 }
2552 EXPORT_SYMBOL_GPL(usb_put_hcd);
2553 
2554 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2555 {
2556 	if (!hcd->primary_hcd)
2557 		return 1;
2558 	return hcd == hcd->primary_hcd;
2559 }
2560 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2561 
2562 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2563 {
2564 	if (!hcd->driver->find_raw_port_number)
2565 		return port1;
2566 
2567 	return hcd->driver->find_raw_port_number(hcd, port1);
2568 }
2569 
2570 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2571 		unsigned int irqnum, unsigned long irqflags)
2572 {
2573 	int retval;
2574 
2575 	if (hcd->driver->irq) {
2576 
2577 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2578 				hcd->driver->description, hcd->self.busnum);
2579 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2580 				hcd->irq_descr, hcd);
2581 		if (retval != 0) {
2582 			dev_err(hcd->self.controller,
2583 					"request interrupt %d failed\n",
2584 					irqnum);
2585 			return retval;
2586 		}
2587 		hcd->irq = irqnum;
2588 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2589 				(hcd->driver->flags & HCD_MEMORY) ?
2590 					"io mem" : "io base",
2591 					(unsigned long long)hcd->rsrc_start);
2592 	} else {
2593 		hcd->irq = 0;
2594 		if (hcd->rsrc_start)
2595 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2596 					(hcd->driver->flags & HCD_MEMORY) ?
2597 					"io mem" : "io base",
2598 					(unsigned long long)hcd->rsrc_start);
2599 	}
2600 	return 0;
2601 }
2602 
2603 /*
2604  * Before we free this root hub, flush in-flight peering attempts
2605  * and disable peer lookups
2606  */
2607 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2608 {
2609 	struct usb_device *rhdev;
2610 
2611 	mutex_lock(&usb_port_peer_mutex);
2612 	rhdev = hcd->self.root_hub;
2613 	hcd->self.root_hub = NULL;
2614 	mutex_unlock(&usb_port_peer_mutex);
2615 	usb_put_dev(rhdev);
2616 }
2617 
2618 /**
2619  * usb_add_hcd - finish generic HCD structure initialization and register
2620  * @hcd: the usb_hcd structure to initialize
2621  * @irqnum: Interrupt line to allocate
2622  * @irqflags: Interrupt type flags
2623  *
2624  * Finish the remaining parts of generic HCD initialization: allocate the
2625  * buffers of consistent memory, register the bus, request the IRQ line,
2626  * and call the driver's reset() and start() routines.
2627  */
2628 int usb_add_hcd(struct usb_hcd *hcd,
2629 		unsigned int irqnum, unsigned long irqflags)
2630 {
2631 	int retval;
2632 	struct usb_device *rhdev;
2633 
2634 	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
2635 		struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
2636 
2637 		if (IS_ERR(phy)) {
2638 			retval = PTR_ERR(phy);
2639 			if (retval == -EPROBE_DEFER)
2640 				return retval;
2641 		} else {
2642 			retval = usb_phy_init(phy);
2643 			if (retval) {
2644 				usb_put_phy(phy);
2645 				return retval;
2646 			}
2647 			hcd->usb_phy = phy;
2648 			hcd->remove_phy = 1;
2649 		}
2650 	}
2651 
2652 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) {
2653 		struct phy *phy = phy_get(hcd->self.controller, "usb");
2654 
2655 		if (IS_ERR(phy)) {
2656 			retval = PTR_ERR(phy);
2657 			if (retval == -EPROBE_DEFER)
2658 				goto err_phy;
2659 		} else {
2660 			retval = phy_init(phy);
2661 			if (retval) {
2662 				phy_put(phy);
2663 				goto err_phy;
2664 			}
2665 			retval = phy_power_on(phy);
2666 			if (retval) {
2667 				phy_exit(phy);
2668 				phy_put(phy);
2669 				goto err_phy;
2670 			}
2671 			hcd->phy = phy;
2672 			hcd->remove_phy = 1;
2673 		}
2674 	}
2675 
2676 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2677 
2678 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2679 	if (authorized_default < 0 || authorized_default > 1)
2680 		hcd->authorized_default = hcd->wireless ? 0 : 1;
2681 	else
2682 		hcd->authorized_default = authorized_default;
2683 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2684 
2685 	/* HC is in reset state, but accessible.  Now do the one-time init,
2686 	 * bottom up so that hcds can customize the root hubs before hub_wq
2687 	 * starts talking to them.  (Note, bus id is assigned early too.)
2688 	 */
2689 	retval = hcd_buffer_create(hcd);
2690 	if (retval != 0) {
2691 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
2692 		goto err_create_buf;
2693 	}
2694 
2695 	retval = usb_register_bus(&hcd->self);
2696 	if (retval < 0)
2697 		goto err_register_bus;
2698 
2699 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2700 	if (rhdev == NULL) {
2701 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
2702 		retval = -ENOMEM;
2703 		goto err_allocate_root_hub;
2704 	}
2705 	mutex_lock(&usb_port_peer_mutex);
2706 	hcd->self.root_hub = rhdev;
2707 	mutex_unlock(&usb_port_peer_mutex);
2708 
2709 	switch (hcd->speed) {
2710 	case HCD_USB11:
2711 		rhdev->speed = USB_SPEED_FULL;
2712 		break;
2713 	case HCD_USB2:
2714 		rhdev->speed = USB_SPEED_HIGH;
2715 		break;
2716 	case HCD_USB25:
2717 		rhdev->speed = USB_SPEED_WIRELESS;
2718 		break;
2719 	case HCD_USB3:
2720 		rhdev->speed = USB_SPEED_SUPER;
2721 		break;
2722 	default:
2723 		retval = -EINVAL;
2724 		goto err_set_rh_speed;
2725 	}
2726 
2727 	/* wakeup flag init defaults to "everything works" for root hubs,
2728 	 * but drivers can override it in reset() if needed, along with
2729 	 * recording the overall controller's system wakeup capability.
2730 	 */
2731 	device_set_wakeup_capable(&rhdev->dev, 1);
2732 
2733 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2734 	 * registered.  But since the controller can die at any time,
2735 	 * let's initialize the flag before touching the hardware.
2736 	 */
2737 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2738 
2739 	/* "reset" is misnamed; its role is now one-time init. the controller
2740 	 * should already have been reset (and boot firmware kicked off etc).
2741 	 */
2742 	if (hcd->driver->reset) {
2743 		retval = hcd->driver->reset(hcd);
2744 		if (retval < 0) {
2745 			dev_err(hcd->self.controller, "can't setup: %d\n",
2746 					retval);
2747 			goto err_hcd_driver_setup;
2748 		}
2749 	}
2750 	hcd->rh_pollable = 1;
2751 
2752 	/* NOTE: root hub and controller capabilities may not be the same */
2753 	if (device_can_wakeup(hcd->self.controller)
2754 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2755 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2756 
2757 	/* initialize tasklets */
2758 	init_giveback_urb_bh(&hcd->high_prio_bh);
2759 	init_giveback_urb_bh(&hcd->low_prio_bh);
2760 
2761 	/* enable irqs just before we start the controller,
2762 	 * if the BIOS provides legacy PCI irqs.
2763 	 */
2764 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2765 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2766 		if (retval)
2767 			goto err_request_irq;
2768 	}
2769 
2770 	hcd->state = HC_STATE_RUNNING;
2771 	retval = hcd->driver->start(hcd);
2772 	if (retval < 0) {
2773 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2774 		goto err_hcd_driver_start;
2775 	}
2776 
2777 	/* starting here, usbcore will pay attention to this root hub */
2778 	retval = register_root_hub(hcd);
2779 	if (retval != 0)
2780 		goto err_register_root_hub;
2781 
2782 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2783 	if (retval < 0) {
2784 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2785 		       retval);
2786 		goto error_create_attr_group;
2787 	}
2788 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2789 		usb_hcd_poll_rh_status(hcd);
2790 
2791 	return retval;
2792 
2793 error_create_attr_group:
2794 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2795 	if (HC_IS_RUNNING(hcd->state))
2796 		hcd->state = HC_STATE_QUIESCING;
2797 	spin_lock_irq(&hcd_root_hub_lock);
2798 	hcd->rh_registered = 0;
2799 	spin_unlock_irq(&hcd_root_hub_lock);
2800 
2801 #ifdef CONFIG_PM
2802 	cancel_work_sync(&hcd->wakeup_work);
2803 #endif
2804 	mutex_lock(&usb_bus_list_lock);
2805 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2806 	mutex_unlock(&usb_bus_list_lock);
2807 err_register_root_hub:
2808 	hcd->rh_pollable = 0;
2809 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2810 	del_timer_sync(&hcd->rh_timer);
2811 	hcd->driver->stop(hcd);
2812 	hcd->state = HC_STATE_HALT;
2813 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2814 	del_timer_sync(&hcd->rh_timer);
2815 err_hcd_driver_start:
2816 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2817 		free_irq(irqnum, hcd);
2818 err_request_irq:
2819 err_hcd_driver_setup:
2820 err_set_rh_speed:
2821 	usb_put_invalidate_rhdev(hcd);
2822 err_allocate_root_hub:
2823 	usb_deregister_bus(&hcd->self);
2824 err_register_bus:
2825 	hcd_buffer_destroy(hcd);
2826 err_create_buf:
2827 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2828 		phy_power_off(hcd->phy);
2829 		phy_exit(hcd->phy);
2830 		phy_put(hcd->phy);
2831 		hcd->phy = NULL;
2832 	}
2833 err_phy:
2834 	if (hcd->remove_phy && hcd->usb_phy) {
2835 		usb_phy_shutdown(hcd->usb_phy);
2836 		usb_put_phy(hcd->usb_phy);
2837 		hcd->usb_phy = NULL;
2838 	}
2839 	return retval;
2840 }
2841 EXPORT_SYMBOL_GPL(usb_add_hcd);
2842 
2843 /**
2844  * usb_remove_hcd - shutdown processing for generic HCDs
2845  * @hcd: the usb_hcd structure to remove
2846  * Context: !in_interrupt()
2847  *
2848  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2849  * invoking the HCD's stop() method.
2850  */
2851 void usb_remove_hcd(struct usb_hcd *hcd)
2852 {
2853 	struct usb_device *rhdev = hcd->self.root_hub;
2854 
2855 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2856 
2857 	usb_get_dev(rhdev);
2858 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2859 
2860 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2861 	if (HC_IS_RUNNING (hcd->state))
2862 		hcd->state = HC_STATE_QUIESCING;
2863 
2864 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2865 	spin_lock_irq (&hcd_root_hub_lock);
2866 	hcd->rh_registered = 0;
2867 	spin_unlock_irq (&hcd_root_hub_lock);
2868 
2869 #ifdef CONFIG_PM
2870 	cancel_work_sync(&hcd->wakeup_work);
2871 #endif
2872 
2873 	mutex_lock(&usb_bus_list_lock);
2874 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2875 	mutex_unlock(&usb_bus_list_lock);
2876 
2877 	/*
2878 	 * tasklet_kill() isn't needed here because:
2879 	 * - driver's disconnect() called from usb_disconnect() should
2880 	 *   make sure its URBs are completed during the disconnect()
2881 	 *   callback
2882 	 *
2883 	 * - it is too late to run complete() here since driver may have
2884 	 *   been removed already now
2885 	 */
2886 
2887 	/* Prevent any more root-hub status calls from the timer.
2888 	 * The HCD might still restart the timer (if a port status change
2889 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2890 	 * the hub_status_data() callback.
2891 	 */
2892 	hcd->rh_pollable = 0;
2893 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2894 	del_timer_sync(&hcd->rh_timer);
2895 
2896 	hcd->driver->stop(hcd);
2897 	hcd->state = HC_STATE_HALT;
2898 
2899 	/* In case the HCD restarted the timer, stop it again. */
2900 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2901 	del_timer_sync(&hcd->rh_timer);
2902 
2903 	if (usb_hcd_is_primary_hcd(hcd)) {
2904 		if (hcd->irq > 0)
2905 			free_irq(hcd->irq, hcd);
2906 	}
2907 
2908 	usb_deregister_bus(&hcd->self);
2909 	hcd_buffer_destroy(hcd);
2910 
2911 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2912 		phy_power_off(hcd->phy);
2913 		phy_exit(hcd->phy);
2914 		phy_put(hcd->phy);
2915 		hcd->phy = NULL;
2916 	}
2917 	if (hcd->remove_phy && hcd->usb_phy) {
2918 		usb_phy_shutdown(hcd->usb_phy);
2919 		usb_put_phy(hcd->usb_phy);
2920 		hcd->usb_phy = NULL;
2921 	}
2922 
2923 	usb_put_invalidate_rhdev(hcd);
2924 }
2925 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2926 
2927 void
2928 usb_hcd_platform_shutdown(struct platform_device *dev)
2929 {
2930 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2931 
2932 	if (hcd->driver->shutdown)
2933 		hcd->driver->shutdown(hcd);
2934 }
2935 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2936 
2937 /*-------------------------------------------------------------------------*/
2938 
2939 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2940 
2941 struct usb_mon_operations *mon_ops;
2942 
2943 /*
2944  * The registration is unlocked.
2945  * We do it this way because we do not want to lock in hot paths.
2946  *
2947  * Notice that the code is minimally error-proof. Because usbmon needs
2948  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2949  */
2950 
2951 int usb_mon_register (struct usb_mon_operations *ops)
2952 {
2953 
2954 	if (mon_ops)
2955 		return -EBUSY;
2956 
2957 	mon_ops = ops;
2958 	mb();
2959 	return 0;
2960 }
2961 EXPORT_SYMBOL_GPL (usb_mon_register);
2962 
2963 void usb_mon_deregister (void)
2964 {
2965 
2966 	if (mon_ops == NULL) {
2967 		printk(KERN_ERR "USB: monitor was not registered\n");
2968 		return;
2969 	}
2970 	mon_ops = NULL;
2971 	mb();
2972 }
2973 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2974 
2975 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2976