xref: /linux/drivers/usb/core/hcd.c (revision 8c749ce93ee69e789e46b3be98de9e0cbfcf8ed8)
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 	USB_DT_DEVICE, /* __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 	USB_DT_DEVICE, /* __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 	USB_DT_DEVICE, /* __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 	USB_DT_DEVICE, /* __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 	USB_DT_CONFIG, /* __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 	USB_DT_INTERFACE,  /* __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 	USB_DT_ENDPOINT, /* __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 	USB_DT_CONFIG, /* __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 	USB_DT_INTERFACE, /* __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 	USB_DT_ENDPOINT, /* __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 	USB_DT_CONFIG, /* __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 	USB_DT_INTERFACE, /* __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 	USB_DT_ENDPOINT, /* __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 	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
357 		     /* Companion */
358 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
359 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
360 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
361 };
362 
363 /* authorized_default behaviour:
364  * -1 is authorized for all devices except wireless (old behaviour)
365  * 0 is unauthorized for all devices
366  * 1 is authorized for all devices
367  */
368 static int authorized_default = -1;
369 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
370 MODULE_PARM_DESC(authorized_default,
371 		"Default USB device authorization: 0 is not authorized, 1 is "
372 		"authorized, -1 is authorized except for wireless USB (default, "
373 		"old behaviour");
374 /*-------------------------------------------------------------------------*/
375 
376 /**
377  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
378  * @s: Null-terminated ASCII (actually ISO-8859-1) string
379  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
380  * @len: Length (in bytes; may be odd) of descriptor buffer.
381  *
382  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
383  * whichever is less.
384  *
385  * Note:
386  * USB String descriptors can contain at most 126 characters; input
387  * strings longer than that are truncated.
388  */
389 static unsigned
390 ascii2desc(char const *s, u8 *buf, unsigned len)
391 {
392 	unsigned n, t = 2 + 2*strlen(s);
393 
394 	if (t > 254)
395 		t = 254;	/* Longest possible UTF string descriptor */
396 	if (len > t)
397 		len = t;
398 
399 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
400 
401 	n = len;
402 	while (n--) {
403 		*buf++ = t;
404 		if (!n--)
405 			break;
406 		*buf++ = t >> 8;
407 		t = (unsigned char)*s++;
408 	}
409 	return len;
410 }
411 
412 /**
413  * rh_string() - provides string descriptors for root hub
414  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
415  * @hcd: the host controller for this root hub
416  * @data: buffer for output packet
417  * @len: length of the provided buffer
418  *
419  * Produces either a manufacturer, product or serial number string for the
420  * virtual root hub device.
421  *
422  * Return: The number of bytes filled in: the length of the descriptor or
423  * of the provided buffer, whichever is less.
424  */
425 static unsigned
426 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
427 {
428 	char buf[100];
429 	char const *s;
430 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
431 
432 	/* language ids */
433 	switch (id) {
434 	case 0:
435 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
436 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
437 		if (len > 4)
438 			len = 4;
439 		memcpy(data, langids, len);
440 		return len;
441 	case 1:
442 		/* Serial number */
443 		s = hcd->self.bus_name;
444 		break;
445 	case 2:
446 		/* Product name */
447 		s = hcd->product_desc;
448 		break;
449 	case 3:
450 		/* Manufacturer */
451 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
452 			init_utsname()->release, hcd->driver->description);
453 		s = buf;
454 		break;
455 	default:
456 		/* Can't happen; caller guarantees it */
457 		return 0;
458 	}
459 
460 	return ascii2desc(s, data, len);
461 }
462 
463 
464 /* Root hub control transfers execute synchronously */
465 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
466 {
467 	struct usb_ctrlrequest *cmd;
468 	u16		typeReq, wValue, wIndex, wLength;
469 	u8		*ubuf = urb->transfer_buffer;
470 	unsigned	len = 0;
471 	int		status;
472 	u8		patch_wakeup = 0;
473 	u8		patch_protocol = 0;
474 	u16		tbuf_size;
475 	u8		*tbuf = NULL;
476 	const u8	*bufp;
477 
478 	might_sleep();
479 
480 	spin_lock_irq(&hcd_root_hub_lock);
481 	status = usb_hcd_link_urb_to_ep(hcd, urb);
482 	spin_unlock_irq(&hcd_root_hub_lock);
483 	if (status)
484 		return status;
485 	urb->hcpriv = hcd;	/* Indicate it's queued */
486 
487 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
488 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
489 	wValue   = le16_to_cpu (cmd->wValue);
490 	wIndex   = le16_to_cpu (cmd->wIndex);
491 	wLength  = le16_to_cpu (cmd->wLength);
492 
493 	if (wLength > urb->transfer_buffer_length)
494 		goto error;
495 
496 	/*
497 	 * tbuf should be at least as big as the
498 	 * USB hub descriptor.
499 	 */
500 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
501 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
502 	if (!tbuf)
503 		return -ENOMEM;
504 
505 	bufp = tbuf;
506 
507 
508 	urb->actual_length = 0;
509 	switch (typeReq) {
510 
511 	/* DEVICE REQUESTS */
512 
513 	/* The root hub's remote wakeup enable bit is implemented using
514 	 * driver model wakeup flags.  If this system supports wakeup
515 	 * through USB, userspace may change the default "allow wakeup"
516 	 * policy through sysfs or these calls.
517 	 *
518 	 * Most root hubs support wakeup from downstream devices, for
519 	 * runtime power management (disabling USB clocks and reducing
520 	 * VBUS power usage).  However, not all of them do so; silicon,
521 	 * board, and BIOS bugs here are not uncommon, so these can't
522 	 * be treated quite like external hubs.
523 	 *
524 	 * Likewise, not all root hubs will pass wakeup events upstream,
525 	 * to wake up the whole system.  So don't assume root hub and
526 	 * controller capabilities are identical.
527 	 */
528 
529 	case DeviceRequest | USB_REQ_GET_STATUS:
530 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
531 					<< USB_DEVICE_REMOTE_WAKEUP)
532 				| (1 << USB_DEVICE_SELF_POWERED);
533 		tbuf[1] = 0;
534 		len = 2;
535 		break;
536 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
537 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
538 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
539 		else
540 			goto error;
541 		break;
542 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
543 		if (device_can_wakeup(&hcd->self.root_hub->dev)
544 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
545 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
546 		else
547 			goto error;
548 		break;
549 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
550 		tbuf[0] = 1;
551 		len = 1;
552 			/* FALLTHROUGH */
553 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
554 		break;
555 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
556 		switch (wValue & 0xff00) {
557 		case USB_DT_DEVICE << 8:
558 			switch (hcd->speed) {
559 			case HCD_USB31:
560 			case HCD_USB3:
561 				bufp = usb3_rh_dev_descriptor;
562 				break;
563 			case HCD_USB25:
564 				bufp = usb25_rh_dev_descriptor;
565 				break;
566 			case HCD_USB2:
567 				bufp = usb2_rh_dev_descriptor;
568 				break;
569 			case HCD_USB11:
570 				bufp = usb11_rh_dev_descriptor;
571 				break;
572 			default:
573 				goto error;
574 			}
575 			len = 18;
576 			if (hcd->has_tt)
577 				patch_protocol = 1;
578 			break;
579 		case USB_DT_CONFIG << 8:
580 			switch (hcd->speed) {
581 			case HCD_USB31:
582 			case HCD_USB3:
583 				bufp = ss_rh_config_descriptor;
584 				len = sizeof ss_rh_config_descriptor;
585 				break;
586 			case HCD_USB25:
587 			case HCD_USB2:
588 				bufp = hs_rh_config_descriptor;
589 				len = sizeof hs_rh_config_descriptor;
590 				break;
591 			case HCD_USB11:
592 				bufp = fs_rh_config_descriptor;
593 				len = sizeof fs_rh_config_descriptor;
594 				break;
595 			default:
596 				goto error;
597 			}
598 			if (device_can_wakeup(&hcd->self.root_hub->dev))
599 				patch_wakeup = 1;
600 			break;
601 		case USB_DT_STRING << 8:
602 			if ((wValue & 0xff) < 4)
603 				urb->actual_length = rh_string(wValue & 0xff,
604 						hcd, ubuf, wLength);
605 			else /* unsupported IDs --> "protocol stall" */
606 				goto error;
607 			break;
608 		case USB_DT_BOS << 8:
609 			goto nongeneric;
610 		default:
611 			goto error;
612 		}
613 		break;
614 	case DeviceRequest | USB_REQ_GET_INTERFACE:
615 		tbuf[0] = 0;
616 		len = 1;
617 			/* FALLTHROUGH */
618 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
619 		break;
620 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
621 		/* wValue == urb->dev->devaddr */
622 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
623 			wValue);
624 		break;
625 
626 	/* INTERFACE REQUESTS (no defined feature/status flags) */
627 
628 	/* ENDPOINT REQUESTS */
629 
630 	case EndpointRequest | USB_REQ_GET_STATUS:
631 		/* ENDPOINT_HALT flag */
632 		tbuf[0] = 0;
633 		tbuf[1] = 0;
634 		len = 2;
635 			/* FALLTHROUGH */
636 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
637 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
638 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
639 		break;
640 
641 	/* CLASS REQUESTS (and errors) */
642 
643 	default:
644 nongeneric:
645 		/* non-generic request */
646 		switch (typeReq) {
647 		case GetHubStatus:
648 		case GetPortStatus:
649 			len = 4;
650 			break;
651 		case GetHubDescriptor:
652 			len = sizeof (struct usb_hub_descriptor);
653 			break;
654 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
655 			/* len is returned by hub_control */
656 			break;
657 		}
658 		status = hcd->driver->hub_control (hcd,
659 			typeReq, wValue, wIndex,
660 			tbuf, wLength);
661 
662 		if (typeReq == GetHubDescriptor)
663 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
664 				(struct usb_hub_descriptor *)tbuf);
665 		break;
666 error:
667 		/* "protocol stall" on error */
668 		status = -EPIPE;
669 	}
670 
671 	if (status < 0) {
672 		len = 0;
673 		if (status != -EPIPE) {
674 			dev_dbg (hcd->self.controller,
675 				"CTRL: TypeReq=0x%x val=0x%x "
676 				"idx=0x%x len=%d ==> %d\n",
677 				typeReq, wValue, wIndex,
678 				wLength, status);
679 		}
680 	} else if (status > 0) {
681 		/* hub_control may return the length of data copied. */
682 		len = status;
683 		status = 0;
684 	}
685 	if (len) {
686 		if (urb->transfer_buffer_length < len)
687 			len = urb->transfer_buffer_length;
688 		urb->actual_length = len;
689 		/* always USB_DIR_IN, toward host */
690 		memcpy (ubuf, bufp, len);
691 
692 		/* report whether RH hardware supports remote wakeup */
693 		if (patch_wakeup &&
694 				len > offsetof (struct usb_config_descriptor,
695 						bmAttributes))
696 			((struct usb_config_descriptor *)ubuf)->bmAttributes
697 				|= USB_CONFIG_ATT_WAKEUP;
698 
699 		/* report whether RH hardware has an integrated TT */
700 		if (patch_protocol &&
701 				len > offsetof(struct usb_device_descriptor,
702 						bDeviceProtocol))
703 			((struct usb_device_descriptor *) ubuf)->
704 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
705 	}
706 
707 	kfree(tbuf);
708 
709 	/* any errors get returned through the urb completion */
710 	spin_lock_irq(&hcd_root_hub_lock);
711 	usb_hcd_unlink_urb_from_ep(hcd, urb);
712 	usb_hcd_giveback_urb(hcd, urb, status);
713 	spin_unlock_irq(&hcd_root_hub_lock);
714 	return 0;
715 }
716 
717 /*-------------------------------------------------------------------------*/
718 
719 /*
720  * Root Hub interrupt transfers are polled using a timer if the
721  * driver requests it; otherwise the driver is responsible for
722  * calling usb_hcd_poll_rh_status() when an event occurs.
723  *
724  * Completions are called in_interrupt(), but they may or may not
725  * be in_irq().
726  */
727 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
728 {
729 	struct urb	*urb;
730 	int		length;
731 	unsigned long	flags;
732 	char		buffer[6];	/* Any root hubs with > 31 ports? */
733 
734 	if (unlikely(!hcd->rh_pollable))
735 		return;
736 	if (!hcd->uses_new_polling && !hcd->status_urb)
737 		return;
738 
739 	length = hcd->driver->hub_status_data(hcd, buffer);
740 	if (length > 0) {
741 
742 		/* try to complete the status urb */
743 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
744 		urb = hcd->status_urb;
745 		if (urb) {
746 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
747 			hcd->status_urb = NULL;
748 			urb->actual_length = length;
749 			memcpy(urb->transfer_buffer, buffer, length);
750 
751 			usb_hcd_unlink_urb_from_ep(hcd, urb);
752 			usb_hcd_giveback_urb(hcd, urb, 0);
753 		} else {
754 			length = 0;
755 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
756 		}
757 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
758 	}
759 
760 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
761 	 * exceed that limit if HZ is 100. The math is more clunky than
762 	 * maybe expected, this is to make sure that all timers for USB devices
763 	 * fire at the same time to give the CPU a break in between */
764 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
765 			(length == 0 && hcd->status_urb != NULL))
766 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
767 }
768 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
769 
770 /* timer callback */
771 static void rh_timer_func (unsigned long _hcd)
772 {
773 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
774 }
775 
776 /*-------------------------------------------------------------------------*/
777 
778 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
779 {
780 	int		retval;
781 	unsigned long	flags;
782 	unsigned	len = 1 + (urb->dev->maxchild / 8);
783 
784 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
785 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
786 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
787 		retval = -EINVAL;
788 		goto done;
789 	}
790 
791 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
792 	if (retval)
793 		goto done;
794 
795 	hcd->status_urb = urb;
796 	urb->hcpriv = hcd;	/* indicate it's queued */
797 	if (!hcd->uses_new_polling)
798 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
799 
800 	/* If a status change has already occurred, report it ASAP */
801 	else if (HCD_POLL_PENDING(hcd))
802 		mod_timer(&hcd->rh_timer, jiffies);
803 	retval = 0;
804  done:
805 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
806 	return retval;
807 }
808 
809 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
810 {
811 	if (usb_endpoint_xfer_int(&urb->ep->desc))
812 		return rh_queue_status (hcd, urb);
813 	if (usb_endpoint_xfer_control(&urb->ep->desc))
814 		return rh_call_control (hcd, urb);
815 	return -EINVAL;
816 }
817 
818 /*-------------------------------------------------------------------------*/
819 
820 /* Unlinks of root-hub control URBs are legal, but they don't do anything
821  * since these URBs always execute synchronously.
822  */
823 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
824 {
825 	unsigned long	flags;
826 	int		rc;
827 
828 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
829 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
830 	if (rc)
831 		goto done;
832 
833 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
834 		;	/* Do nothing */
835 
836 	} else {				/* Status URB */
837 		if (!hcd->uses_new_polling)
838 			del_timer (&hcd->rh_timer);
839 		if (urb == hcd->status_urb) {
840 			hcd->status_urb = NULL;
841 			usb_hcd_unlink_urb_from_ep(hcd, urb);
842 			usb_hcd_giveback_urb(hcd, urb, status);
843 		}
844 	}
845  done:
846 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
847 	return rc;
848 }
849 
850 
851 
852 /*
853  * Show & store the current value of authorized_default
854  */
855 static ssize_t authorized_default_show(struct device *dev,
856 				       struct device_attribute *attr, char *buf)
857 {
858 	struct usb_device *rh_usb_dev = to_usb_device(dev);
859 	struct usb_bus *usb_bus = rh_usb_dev->bus;
860 	struct usb_hcd *hcd;
861 
862 	hcd = bus_to_hcd(usb_bus);
863 	return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
864 }
865 
866 static ssize_t authorized_default_store(struct device *dev,
867 					struct device_attribute *attr,
868 					const char *buf, size_t size)
869 {
870 	ssize_t result;
871 	unsigned val;
872 	struct usb_device *rh_usb_dev = to_usb_device(dev);
873 	struct usb_bus *usb_bus = rh_usb_dev->bus;
874 	struct usb_hcd *hcd;
875 
876 	hcd = bus_to_hcd(usb_bus);
877 	result = sscanf(buf, "%u\n", &val);
878 	if (result == 1) {
879 		if (val)
880 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
881 		else
882 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
883 
884 		result = size;
885 	} else {
886 		result = -EINVAL;
887 	}
888 	return result;
889 }
890 static DEVICE_ATTR_RW(authorized_default);
891 
892 /*
893  * interface_authorized_default_show - show default authorization status
894  * for USB interfaces
895  *
896  * note: interface_authorized_default is the default value
897  *       for initializing the authorized attribute of interfaces
898  */
899 static ssize_t interface_authorized_default_show(struct device *dev,
900 		struct device_attribute *attr, char *buf)
901 {
902 	struct usb_device *usb_dev = to_usb_device(dev);
903 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
904 
905 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
906 }
907 
908 /*
909  * interface_authorized_default_store - store default authorization status
910  * for USB interfaces
911  *
912  * note: interface_authorized_default is the default value
913  *       for initializing the authorized attribute of interfaces
914  */
915 static ssize_t interface_authorized_default_store(struct device *dev,
916 		struct device_attribute *attr, const char *buf, size_t count)
917 {
918 	struct usb_device *usb_dev = to_usb_device(dev);
919 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
920 	int rc = count;
921 	bool val;
922 
923 	if (strtobool(buf, &val) != 0)
924 		return -EINVAL;
925 
926 	if (val)
927 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
928 	else
929 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
930 
931 	return rc;
932 }
933 static DEVICE_ATTR_RW(interface_authorized_default);
934 
935 /* Group all the USB bus attributes */
936 static struct attribute *usb_bus_attrs[] = {
937 		&dev_attr_authorized_default.attr,
938 		&dev_attr_interface_authorized_default.attr,
939 		NULL,
940 };
941 
942 static struct attribute_group usb_bus_attr_group = {
943 	.name = NULL,	/* we want them in the same directory */
944 	.attrs = usb_bus_attrs,
945 };
946 
947 
948 
949 /*-------------------------------------------------------------------------*/
950 
951 /**
952  * usb_bus_init - shared initialization code
953  * @bus: the bus structure being initialized
954  *
955  * This code is used to initialize a usb_bus structure, memory for which is
956  * separately managed.
957  */
958 static void usb_bus_init (struct usb_bus *bus)
959 {
960 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
961 
962 	bus->devnum_next = 1;
963 
964 	bus->root_hub = NULL;
965 	bus->busnum = -1;
966 	bus->bandwidth_allocated = 0;
967 	bus->bandwidth_int_reqs  = 0;
968 	bus->bandwidth_isoc_reqs = 0;
969 	mutex_init(&bus->usb_address0_mutex);
970 
971 	INIT_LIST_HEAD (&bus->bus_list);
972 }
973 
974 /*-------------------------------------------------------------------------*/
975 
976 /**
977  * usb_register_bus - registers the USB host controller with the usb core
978  * @bus: pointer to the bus to register
979  * Context: !in_interrupt()
980  *
981  * Assigns a bus number, and links the controller into usbcore data
982  * structures so that it can be seen by scanning the bus list.
983  *
984  * Return: 0 if successful. A negative error code otherwise.
985  */
986 static int usb_register_bus(struct usb_bus *bus)
987 {
988 	int result = -E2BIG;
989 	int busnum;
990 
991 	mutex_lock(&usb_bus_list_lock);
992 	busnum = find_next_zero_bit(busmap, USB_MAXBUS, 1);
993 	if (busnum >= USB_MAXBUS) {
994 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
995 		goto error_find_busnum;
996 	}
997 	set_bit(busnum, busmap);
998 	bus->busnum = busnum;
999 
1000 	/* Add it to the local list of buses */
1001 	list_add (&bus->bus_list, &usb_bus_list);
1002 	mutex_unlock(&usb_bus_list_lock);
1003 
1004 	usb_notify_add_bus(bus);
1005 
1006 	dev_info (bus->controller, "new USB bus registered, assigned bus "
1007 		  "number %d\n", bus->busnum);
1008 	return 0;
1009 
1010 error_find_busnum:
1011 	mutex_unlock(&usb_bus_list_lock);
1012 	return result;
1013 }
1014 
1015 /**
1016  * usb_deregister_bus - deregisters the USB host controller
1017  * @bus: pointer to the bus to deregister
1018  * Context: !in_interrupt()
1019  *
1020  * Recycles the bus number, and unlinks the controller from usbcore data
1021  * structures so that it won't be seen by scanning the bus list.
1022  */
1023 static void usb_deregister_bus (struct usb_bus *bus)
1024 {
1025 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1026 
1027 	/*
1028 	 * NOTE: make sure that all the devices are removed by the
1029 	 * controller code, as well as having it call this when cleaning
1030 	 * itself up
1031 	 */
1032 	mutex_lock(&usb_bus_list_lock);
1033 	list_del (&bus->bus_list);
1034 	mutex_unlock(&usb_bus_list_lock);
1035 
1036 	usb_notify_remove_bus(bus);
1037 
1038 	clear_bit(bus->busnum, busmap);
1039 }
1040 
1041 /**
1042  * register_root_hub - called by usb_add_hcd() to register a root hub
1043  * @hcd: host controller for this root hub
1044  *
1045  * This function registers the root hub with the USB subsystem.  It sets up
1046  * the device properly in the device tree and then calls usb_new_device()
1047  * to register the usb device.  It also assigns the root hub's USB address
1048  * (always 1).
1049  *
1050  * Return: 0 if successful. A negative error code otherwise.
1051  */
1052 static int register_root_hub(struct usb_hcd *hcd)
1053 {
1054 	struct device *parent_dev = hcd->self.controller;
1055 	struct usb_device *usb_dev = hcd->self.root_hub;
1056 	const int devnum = 1;
1057 	int retval;
1058 
1059 	usb_dev->devnum = devnum;
1060 	usb_dev->bus->devnum_next = devnum + 1;
1061 	memset (&usb_dev->bus->devmap.devicemap, 0,
1062 			sizeof usb_dev->bus->devmap.devicemap);
1063 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1064 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1065 
1066 	mutex_lock(&usb_bus_list_lock);
1067 
1068 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1069 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1070 	if (retval != sizeof usb_dev->descriptor) {
1071 		mutex_unlock(&usb_bus_list_lock);
1072 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1073 				dev_name(&usb_dev->dev), retval);
1074 		return (retval < 0) ? retval : -EMSGSIZE;
1075 	}
1076 
1077 	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1078 		retval = usb_get_bos_descriptor(usb_dev);
1079 		if (!retval) {
1080 			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1081 		} else if (usb_dev->speed == USB_SPEED_SUPER) {
1082 			mutex_unlock(&usb_bus_list_lock);
1083 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1084 					dev_name(&usb_dev->dev), retval);
1085 			return retval;
1086 		}
1087 	}
1088 
1089 	retval = usb_new_device (usb_dev);
1090 	if (retval) {
1091 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1092 				dev_name(&usb_dev->dev), retval);
1093 	} else {
1094 		spin_lock_irq (&hcd_root_hub_lock);
1095 		hcd->rh_registered = 1;
1096 		spin_unlock_irq (&hcd_root_hub_lock);
1097 
1098 		/* Did the HC die before the root hub was registered? */
1099 		if (HCD_DEAD(hcd))
1100 			usb_hc_died (hcd);	/* This time clean up */
1101 	}
1102 	mutex_unlock(&usb_bus_list_lock);
1103 
1104 	return retval;
1105 }
1106 
1107 /*
1108  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1109  * @bus: the bus which the root hub belongs to
1110  * @portnum: the port which is being resumed
1111  *
1112  * HCDs should call this function when they know that a resume signal is
1113  * being sent to a root-hub port.  The root hub will be prevented from
1114  * going into autosuspend until usb_hcd_end_port_resume() is called.
1115  *
1116  * The bus's private lock must be held by the caller.
1117  */
1118 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1119 {
1120 	unsigned bit = 1 << portnum;
1121 
1122 	if (!(bus->resuming_ports & bit)) {
1123 		bus->resuming_ports |= bit;
1124 		pm_runtime_get_noresume(&bus->root_hub->dev);
1125 	}
1126 }
1127 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1128 
1129 /*
1130  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1131  * @bus: the bus which the root hub belongs to
1132  * @portnum: the port which is being resumed
1133  *
1134  * HCDs should call this function when they know that a resume signal has
1135  * stopped being sent to a root-hub port.  The root hub will be allowed to
1136  * autosuspend again.
1137  *
1138  * The bus's private lock must be held by the caller.
1139  */
1140 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1141 {
1142 	unsigned bit = 1 << portnum;
1143 
1144 	if (bus->resuming_ports & bit) {
1145 		bus->resuming_ports &= ~bit;
1146 		pm_runtime_put_noidle(&bus->root_hub->dev);
1147 	}
1148 }
1149 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1150 
1151 /*-------------------------------------------------------------------------*/
1152 
1153 /**
1154  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1155  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1156  * @is_input: true iff the transaction sends data to the host
1157  * @isoc: true for isochronous transactions, false for interrupt ones
1158  * @bytecount: how many bytes in the transaction.
1159  *
1160  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1161  *
1162  * Note:
1163  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1164  * scheduled in software, this function is only used for such scheduling.
1165  */
1166 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1167 {
1168 	unsigned long	tmp;
1169 
1170 	switch (speed) {
1171 	case USB_SPEED_LOW: 	/* INTR only */
1172 		if (is_input) {
1173 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1174 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1175 		} else {
1176 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1177 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1178 		}
1179 	case USB_SPEED_FULL:	/* ISOC or INTR */
1180 		if (isoc) {
1181 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1182 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1183 		} else {
1184 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1185 			return 9107L + BW_HOST_DELAY + tmp;
1186 		}
1187 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1188 		/* FIXME adjust for input vs output */
1189 		if (isoc)
1190 			tmp = HS_NSECS_ISO (bytecount);
1191 		else
1192 			tmp = HS_NSECS (bytecount);
1193 		return tmp;
1194 	default:
1195 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1196 		return -1;
1197 	}
1198 }
1199 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1200 
1201 
1202 /*-------------------------------------------------------------------------*/
1203 
1204 /*
1205  * Generic HC operations.
1206  */
1207 
1208 /*-------------------------------------------------------------------------*/
1209 
1210 /**
1211  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1212  * @hcd: host controller to which @urb was submitted
1213  * @urb: URB being submitted
1214  *
1215  * Host controller drivers should call this routine in their enqueue()
1216  * method.  The HCD's private spinlock must be held and interrupts must
1217  * be disabled.  The actions carried out here are required for URB
1218  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1219  *
1220  * Return: 0 for no error, otherwise a negative error code (in which case
1221  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1222  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1223  * the private spinlock and returning.
1224  */
1225 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1226 {
1227 	int		rc = 0;
1228 
1229 	spin_lock(&hcd_urb_list_lock);
1230 
1231 	/* Check that the URB isn't being killed */
1232 	if (unlikely(atomic_read(&urb->reject))) {
1233 		rc = -EPERM;
1234 		goto done;
1235 	}
1236 
1237 	if (unlikely(!urb->ep->enabled)) {
1238 		rc = -ENOENT;
1239 		goto done;
1240 	}
1241 
1242 	if (unlikely(!urb->dev->can_submit)) {
1243 		rc = -EHOSTUNREACH;
1244 		goto done;
1245 	}
1246 
1247 	/*
1248 	 * Check the host controller's state and add the URB to the
1249 	 * endpoint's queue.
1250 	 */
1251 	if (HCD_RH_RUNNING(hcd)) {
1252 		urb->unlinked = 0;
1253 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1254 	} else {
1255 		rc = -ESHUTDOWN;
1256 		goto done;
1257 	}
1258  done:
1259 	spin_unlock(&hcd_urb_list_lock);
1260 	return rc;
1261 }
1262 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1263 
1264 /**
1265  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1266  * @hcd: host controller to which @urb was submitted
1267  * @urb: URB being checked for unlinkability
1268  * @status: error code to store in @urb if the unlink succeeds
1269  *
1270  * Host controller drivers should call this routine in their dequeue()
1271  * method.  The HCD's private spinlock must be held and interrupts must
1272  * be disabled.  The actions carried out here are required for making
1273  * sure than an unlink is valid.
1274  *
1275  * Return: 0 for no error, otherwise a negative error code (in which case
1276  * the dequeue() method must fail).  The possible error codes are:
1277  *
1278  *	-EIDRM: @urb was not submitted or has already completed.
1279  *		The completion function may not have been called yet.
1280  *
1281  *	-EBUSY: @urb has already been unlinked.
1282  */
1283 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1284 		int status)
1285 {
1286 	struct list_head	*tmp;
1287 
1288 	/* insist the urb is still queued */
1289 	list_for_each(tmp, &urb->ep->urb_list) {
1290 		if (tmp == &urb->urb_list)
1291 			break;
1292 	}
1293 	if (tmp != &urb->urb_list)
1294 		return -EIDRM;
1295 
1296 	/* Any status except -EINPROGRESS means something already started to
1297 	 * unlink this URB from the hardware.  So there's no more work to do.
1298 	 */
1299 	if (urb->unlinked)
1300 		return -EBUSY;
1301 	urb->unlinked = status;
1302 	return 0;
1303 }
1304 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1305 
1306 /**
1307  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1308  * @hcd: host controller to which @urb was submitted
1309  * @urb: URB being unlinked
1310  *
1311  * Host controller drivers should call this routine before calling
1312  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1313  * interrupts must be disabled.  The actions carried out here are required
1314  * for URB completion.
1315  */
1316 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1317 {
1318 	/* clear all state linking urb to this dev (and hcd) */
1319 	spin_lock(&hcd_urb_list_lock);
1320 	list_del_init(&urb->urb_list);
1321 	spin_unlock(&hcd_urb_list_lock);
1322 }
1323 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1324 
1325 /*
1326  * Some usb host controllers can only perform dma using a small SRAM area.
1327  * The usb core itself is however optimized for host controllers that can dma
1328  * using regular system memory - like pci devices doing bus mastering.
1329  *
1330  * To support host controllers with limited dma capabilities we provide dma
1331  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1332  * For this to work properly the host controller code must first use the
1333  * function dma_declare_coherent_memory() to point out which memory area
1334  * that should be used for dma allocations.
1335  *
1336  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1337  * dma using dma_alloc_coherent() which in turn allocates from the memory
1338  * area pointed out with dma_declare_coherent_memory().
1339  *
1340  * So, to summarize...
1341  *
1342  * - We need "local" memory, canonical example being
1343  *   a small SRAM on a discrete controller being the
1344  *   only memory that the controller can read ...
1345  *   (a) "normal" kernel memory is no good, and
1346  *   (b) there's not enough to share
1347  *
1348  * - The only *portable* hook for such stuff in the
1349  *   DMA framework is dma_declare_coherent_memory()
1350  *
1351  * - So we use that, even though the primary requirement
1352  *   is that the memory be "local" (hence addressable
1353  *   by that device), not "coherent".
1354  *
1355  */
1356 
1357 static int hcd_alloc_coherent(struct usb_bus *bus,
1358 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1359 			      void **vaddr_handle, size_t size,
1360 			      enum dma_data_direction dir)
1361 {
1362 	unsigned char *vaddr;
1363 
1364 	if (*vaddr_handle == NULL) {
1365 		WARN_ON_ONCE(1);
1366 		return -EFAULT;
1367 	}
1368 
1369 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1370 				 mem_flags, dma_handle);
1371 	if (!vaddr)
1372 		return -ENOMEM;
1373 
1374 	/*
1375 	 * Store the virtual address of the buffer at the end
1376 	 * of the allocated dma buffer. The size of the buffer
1377 	 * may be uneven so use unaligned functions instead
1378 	 * of just rounding up. It makes sense to optimize for
1379 	 * memory footprint over access speed since the amount
1380 	 * of memory available for dma may be limited.
1381 	 */
1382 	put_unaligned((unsigned long)*vaddr_handle,
1383 		      (unsigned long *)(vaddr + size));
1384 
1385 	if (dir == DMA_TO_DEVICE)
1386 		memcpy(vaddr, *vaddr_handle, size);
1387 
1388 	*vaddr_handle = vaddr;
1389 	return 0;
1390 }
1391 
1392 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1393 			      void **vaddr_handle, size_t size,
1394 			      enum dma_data_direction dir)
1395 {
1396 	unsigned char *vaddr = *vaddr_handle;
1397 
1398 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1399 
1400 	if (dir == DMA_FROM_DEVICE)
1401 		memcpy(vaddr, *vaddr_handle, size);
1402 
1403 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1404 
1405 	*vaddr_handle = vaddr;
1406 	*dma_handle = 0;
1407 }
1408 
1409 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1410 {
1411 	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1412 		dma_unmap_single(hcd->self.controller,
1413 				urb->setup_dma,
1414 				sizeof(struct usb_ctrlrequest),
1415 				DMA_TO_DEVICE);
1416 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1417 		hcd_free_coherent(urb->dev->bus,
1418 				&urb->setup_dma,
1419 				(void **) &urb->setup_packet,
1420 				sizeof(struct usb_ctrlrequest),
1421 				DMA_TO_DEVICE);
1422 
1423 	/* Make it safe to call this routine more than once */
1424 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1425 }
1426 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1427 
1428 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1429 {
1430 	if (hcd->driver->unmap_urb_for_dma)
1431 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1432 	else
1433 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1434 }
1435 
1436 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1437 {
1438 	enum dma_data_direction dir;
1439 
1440 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1441 
1442 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1443 	if (urb->transfer_flags & URB_DMA_MAP_SG)
1444 		dma_unmap_sg(hcd->self.controller,
1445 				urb->sg,
1446 				urb->num_sgs,
1447 				dir);
1448 	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1449 		dma_unmap_page(hcd->self.controller,
1450 				urb->transfer_dma,
1451 				urb->transfer_buffer_length,
1452 				dir);
1453 	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1454 		dma_unmap_single(hcd->self.controller,
1455 				urb->transfer_dma,
1456 				urb->transfer_buffer_length,
1457 				dir);
1458 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1459 		hcd_free_coherent(urb->dev->bus,
1460 				&urb->transfer_dma,
1461 				&urb->transfer_buffer,
1462 				urb->transfer_buffer_length,
1463 				dir);
1464 
1465 	/* Make it safe to call this routine more than once */
1466 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1467 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1468 }
1469 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1470 
1471 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1472 			   gfp_t mem_flags)
1473 {
1474 	if (hcd->driver->map_urb_for_dma)
1475 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1476 	else
1477 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1478 }
1479 
1480 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1481 			    gfp_t mem_flags)
1482 {
1483 	enum dma_data_direction dir;
1484 	int ret = 0;
1485 
1486 	/* Map the URB's buffers for DMA access.
1487 	 * Lower level HCD code should use *_dma exclusively,
1488 	 * unless it uses pio or talks to another transport,
1489 	 * or uses the provided scatter gather list for bulk.
1490 	 */
1491 
1492 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1493 		if (hcd->self.uses_pio_for_control)
1494 			return ret;
1495 		if (hcd->self.uses_dma) {
1496 			urb->setup_dma = dma_map_single(
1497 					hcd->self.controller,
1498 					urb->setup_packet,
1499 					sizeof(struct usb_ctrlrequest),
1500 					DMA_TO_DEVICE);
1501 			if (dma_mapping_error(hcd->self.controller,
1502 						urb->setup_dma))
1503 				return -EAGAIN;
1504 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1505 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1506 			ret = hcd_alloc_coherent(
1507 					urb->dev->bus, mem_flags,
1508 					&urb->setup_dma,
1509 					(void **)&urb->setup_packet,
1510 					sizeof(struct usb_ctrlrequest),
1511 					DMA_TO_DEVICE);
1512 			if (ret)
1513 				return ret;
1514 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1515 		}
1516 	}
1517 
1518 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1519 	if (urb->transfer_buffer_length != 0
1520 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1521 		if (hcd->self.uses_dma) {
1522 			if (urb->num_sgs) {
1523 				int n;
1524 
1525 				/* We don't support sg for isoc transfers ! */
1526 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1527 					WARN_ON(1);
1528 					return -EINVAL;
1529 				}
1530 
1531 				n = dma_map_sg(
1532 						hcd->self.controller,
1533 						urb->sg,
1534 						urb->num_sgs,
1535 						dir);
1536 				if (n <= 0)
1537 					ret = -EAGAIN;
1538 				else
1539 					urb->transfer_flags |= URB_DMA_MAP_SG;
1540 				urb->num_mapped_sgs = n;
1541 				if (n != urb->num_sgs)
1542 					urb->transfer_flags |=
1543 							URB_DMA_SG_COMBINED;
1544 			} else if (urb->sg) {
1545 				struct scatterlist *sg = urb->sg;
1546 				urb->transfer_dma = dma_map_page(
1547 						hcd->self.controller,
1548 						sg_page(sg),
1549 						sg->offset,
1550 						urb->transfer_buffer_length,
1551 						dir);
1552 				if (dma_mapping_error(hcd->self.controller,
1553 						urb->transfer_dma))
1554 					ret = -EAGAIN;
1555 				else
1556 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1557 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1558 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1559 				ret = -EAGAIN;
1560 			} else {
1561 				urb->transfer_dma = dma_map_single(
1562 						hcd->self.controller,
1563 						urb->transfer_buffer,
1564 						urb->transfer_buffer_length,
1565 						dir);
1566 				if (dma_mapping_error(hcd->self.controller,
1567 						urb->transfer_dma))
1568 					ret = -EAGAIN;
1569 				else
1570 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1571 			}
1572 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1573 			ret = hcd_alloc_coherent(
1574 					urb->dev->bus, mem_flags,
1575 					&urb->transfer_dma,
1576 					&urb->transfer_buffer,
1577 					urb->transfer_buffer_length,
1578 					dir);
1579 			if (ret == 0)
1580 				urb->transfer_flags |= URB_MAP_LOCAL;
1581 		}
1582 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1583 				URB_SETUP_MAP_LOCAL)))
1584 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1585 	}
1586 	return ret;
1587 }
1588 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1589 
1590 /*-------------------------------------------------------------------------*/
1591 
1592 /* may be called in any context with a valid urb->dev usecount
1593  * caller surrenders "ownership" of urb
1594  * expects usb_submit_urb() to have sanity checked and conditioned all
1595  * inputs in the urb
1596  */
1597 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1598 {
1599 	int			status;
1600 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1601 
1602 	/* increment urb's reference count as part of giving it to the HCD
1603 	 * (which will control it).  HCD guarantees that it either returns
1604 	 * an error or calls giveback(), but not both.
1605 	 */
1606 	usb_get_urb(urb);
1607 	atomic_inc(&urb->use_count);
1608 	atomic_inc(&urb->dev->urbnum);
1609 	usbmon_urb_submit(&hcd->self, urb);
1610 
1611 	/* NOTE requirements on root-hub callers (usbfs and the hub
1612 	 * driver, for now):  URBs' urb->transfer_buffer must be
1613 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1614 	 * they could clobber root hub response data.  Also, control
1615 	 * URBs must be submitted in process context with interrupts
1616 	 * enabled.
1617 	 */
1618 
1619 	if (is_root_hub(urb->dev)) {
1620 		status = rh_urb_enqueue(hcd, urb);
1621 	} else {
1622 		status = map_urb_for_dma(hcd, urb, mem_flags);
1623 		if (likely(status == 0)) {
1624 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1625 			if (unlikely(status))
1626 				unmap_urb_for_dma(hcd, urb);
1627 		}
1628 	}
1629 
1630 	if (unlikely(status)) {
1631 		usbmon_urb_submit_error(&hcd->self, urb, status);
1632 		urb->hcpriv = NULL;
1633 		INIT_LIST_HEAD(&urb->urb_list);
1634 		atomic_dec(&urb->use_count);
1635 		atomic_dec(&urb->dev->urbnum);
1636 		if (atomic_read(&urb->reject))
1637 			wake_up(&usb_kill_urb_queue);
1638 		usb_put_urb(urb);
1639 	}
1640 	return status;
1641 }
1642 
1643 /*-------------------------------------------------------------------------*/
1644 
1645 /* this makes the hcd giveback() the urb more quickly, by kicking it
1646  * off hardware queues (which may take a while) and returning it as
1647  * soon as practical.  we've already set up the urb's return status,
1648  * but we can't know if the callback completed already.
1649  */
1650 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1651 {
1652 	int		value;
1653 
1654 	if (is_root_hub(urb->dev))
1655 		value = usb_rh_urb_dequeue(hcd, urb, status);
1656 	else {
1657 
1658 		/* The only reason an HCD might fail this call is if
1659 		 * it has not yet fully queued the urb to begin with.
1660 		 * Such failures should be harmless. */
1661 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1662 	}
1663 	return value;
1664 }
1665 
1666 /*
1667  * called in any context
1668  *
1669  * caller guarantees urb won't be recycled till both unlink()
1670  * and the urb's completion function return
1671  */
1672 int usb_hcd_unlink_urb (struct urb *urb, int status)
1673 {
1674 	struct usb_hcd		*hcd;
1675 	struct usb_device	*udev = urb->dev;
1676 	int			retval = -EIDRM;
1677 	unsigned long		flags;
1678 
1679 	/* Prevent the device and bus from going away while
1680 	 * the unlink is carried out.  If they are already gone
1681 	 * then urb->use_count must be 0, since disconnected
1682 	 * devices can't have any active URBs.
1683 	 */
1684 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1685 	if (atomic_read(&urb->use_count) > 0) {
1686 		retval = 0;
1687 		usb_get_dev(udev);
1688 	}
1689 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1690 	if (retval == 0) {
1691 		hcd = bus_to_hcd(urb->dev->bus);
1692 		retval = unlink1(hcd, urb, status);
1693 		if (retval == 0)
1694 			retval = -EINPROGRESS;
1695 		else if (retval != -EIDRM && retval != -EBUSY)
1696 			dev_dbg(&udev->dev, "hcd_unlink_urb %p fail %d\n",
1697 					urb, retval);
1698 		usb_put_dev(udev);
1699 	}
1700 	return retval;
1701 }
1702 
1703 /*-------------------------------------------------------------------------*/
1704 
1705 static void __usb_hcd_giveback_urb(struct urb *urb)
1706 {
1707 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1708 	struct usb_anchor *anchor = urb->anchor;
1709 	int status = urb->unlinked;
1710 	unsigned long flags;
1711 
1712 	urb->hcpriv = NULL;
1713 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1714 	    urb->actual_length < urb->transfer_buffer_length &&
1715 	    !status))
1716 		status = -EREMOTEIO;
1717 
1718 	unmap_urb_for_dma(hcd, urb);
1719 	usbmon_urb_complete(&hcd->self, urb, status);
1720 	usb_anchor_suspend_wakeups(anchor);
1721 	usb_unanchor_urb(urb);
1722 	if (likely(status == 0))
1723 		usb_led_activity(USB_LED_EVENT_HOST);
1724 
1725 	/* pass ownership to the completion handler */
1726 	urb->status = status;
1727 
1728 	/*
1729 	 * We disable local IRQs here avoid possible deadlock because
1730 	 * drivers may call spin_lock() to hold lock which might be
1731 	 * acquired in one hard interrupt handler.
1732 	 *
1733 	 * The local_irq_save()/local_irq_restore() around complete()
1734 	 * will be removed if current USB drivers have been cleaned up
1735 	 * and no one may trigger the above deadlock situation when
1736 	 * running complete() in tasklet.
1737 	 */
1738 	local_irq_save(flags);
1739 	urb->complete(urb);
1740 	local_irq_restore(flags);
1741 
1742 	usb_anchor_resume_wakeups(anchor);
1743 	atomic_dec(&urb->use_count);
1744 	if (unlikely(atomic_read(&urb->reject)))
1745 		wake_up(&usb_kill_urb_queue);
1746 	usb_put_urb(urb);
1747 }
1748 
1749 static void usb_giveback_urb_bh(unsigned long param)
1750 {
1751 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1752 	struct list_head local_list;
1753 
1754 	spin_lock_irq(&bh->lock);
1755 	bh->running = true;
1756  restart:
1757 	list_replace_init(&bh->head, &local_list);
1758 	spin_unlock_irq(&bh->lock);
1759 
1760 	while (!list_empty(&local_list)) {
1761 		struct urb *urb;
1762 
1763 		urb = list_entry(local_list.next, struct urb, urb_list);
1764 		list_del_init(&urb->urb_list);
1765 		bh->completing_ep = urb->ep;
1766 		__usb_hcd_giveback_urb(urb);
1767 		bh->completing_ep = NULL;
1768 	}
1769 
1770 	/* check if there are new URBs to giveback */
1771 	spin_lock_irq(&bh->lock);
1772 	if (!list_empty(&bh->head))
1773 		goto restart;
1774 	bh->running = false;
1775 	spin_unlock_irq(&bh->lock);
1776 }
1777 
1778 /**
1779  * usb_hcd_giveback_urb - return URB from HCD to device driver
1780  * @hcd: host controller returning the URB
1781  * @urb: urb being returned to the USB device driver.
1782  * @status: completion status code for the URB.
1783  * Context: in_interrupt()
1784  *
1785  * This hands the URB from HCD to its USB device driver, using its
1786  * completion function.  The HCD has freed all per-urb resources
1787  * (and is done using urb->hcpriv).  It also released all HCD locks;
1788  * the device driver won't cause problems if it frees, modifies,
1789  * or resubmits this URB.
1790  *
1791  * If @urb was unlinked, the value of @status will be overridden by
1792  * @urb->unlinked.  Erroneous short transfers are detected in case
1793  * the HCD hasn't checked for them.
1794  */
1795 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1796 {
1797 	struct giveback_urb_bh *bh;
1798 	bool running, high_prio_bh;
1799 
1800 	/* pass status to tasklet via unlinked */
1801 	if (likely(!urb->unlinked))
1802 		urb->unlinked = status;
1803 
1804 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1805 		__usb_hcd_giveback_urb(urb);
1806 		return;
1807 	}
1808 
1809 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1810 		bh = &hcd->high_prio_bh;
1811 		high_prio_bh = true;
1812 	} else {
1813 		bh = &hcd->low_prio_bh;
1814 		high_prio_bh = false;
1815 	}
1816 
1817 	spin_lock(&bh->lock);
1818 	list_add_tail(&urb->urb_list, &bh->head);
1819 	running = bh->running;
1820 	spin_unlock(&bh->lock);
1821 
1822 	if (running)
1823 		;
1824 	else if (high_prio_bh)
1825 		tasklet_hi_schedule(&bh->bh);
1826 	else
1827 		tasklet_schedule(&bh->bh);
1828 }
1829 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1830 
1831 /*-------------------------------------------------------------------------*/
1832 
1833 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1834  * queue to drain completely.  The caller must first insure that no more
1835  * URBs can be submitted for this endpoint.
1836  */
1837 void usb_hcd_flush_endpoint(struct usb_device *udev,
1838 		struct usb_host_endpoint *ep)
1839 {
1840 	struct usb_hcd		*hcd;
1841 	struct urb		*urb;
1842 
1843 	if (!ep)
1844 		return;
1845 	might_sleep();
1846 	hcd = bus_to_hcd(udev->bus);
1847 
1848 	/* No more submits can occur */
1849 	spin_lock_irq(&hcd_urb_list_lock);
1850 rescan:
1851 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1852 		int	is_in;
1853 
1854 		if (urb->unlinked)
1855 			continue;
1856 		usb_get_urb (urb);
1857 		is_in = usb_urb_dir_in(urb);
1858 		spin_unlock(&hcd_urb_list_lock);
1859 
1860 		/* kick hcd */
1861 		unlink1(hcd, urb, -ESHUTDOWN);
1862 		dev_dbg (hcd->self.controller,
1863 			"shutdown urb %p ep%d%s%s\n",
1864 			urb, usb_endpoint_num(&ep->desc),
1865 			is_in ? "in" : "out",
1866 			({	char *s;
1867 
1868 				 switch (usb_endpoint_type(&ep->desc)) {
1869 				 case USB_ENDPOINT_XFER_CONTROL:
1870 					s = ""; break;
1871 				 case USB_ENDPOINT_XFER_BULK:
1872 					s = "-bulk"; break;
1873 				 case USB_ENDPOINT_XFER_INT:
1874 					s = "-intr"; break;
1875 				 default:
1876 					s = "-iso"; break;
1877 				};
1878 				s;
1879 			}));
1880 		usb_put_urb (urb);
1881 
1882 		/* list contents may have changed */
1883 		spin_lock(&hcd_urb_list_lock);
1884 		goto rescan;
1885 	}
1886 	spin_unlock_irq(&hcd_urb_list_lock);
1887 
1888 	/* Wait until the endpoint queue is completely empty */
1889 	while (!list_empty (&ep->urb_list)) {
1890 		spin_lock_irq(&hcd_urb_list_lock);
1891 
1892 		/* The list may have changed while we acquired the spinlock */
1893 		urb = NULL;
1894 		if (!list_empty (&ep->urb_list)) {
1895 			urb = list_entry (ep->urb_list.prev, struct urb,
1896 					urb_list);
1897 			usb_get_urb (urb);
1898 		}
1899 		spin_unlock_irq(&hcd_urb_list_lock);
1900 
1901 		if (urb) {
1902 			usb_kill_urb (urb);
1903 			usb_put_urb (urb);
1904 		}
1905 	}
1906 }
1907 
1908 /**
1909  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1910  *				the bus bandwidth
1911  * @udev: target &usb_device
1912  * @new_config: new configuration to install
1913  * @cur_alt: the current alternate interface setting
1914  * @new_alt: alternate interface setting that is being installed
1915  *
1916  * To change configurations, pass in the new configuration in new_config,
1917  * and pass NULL for cur_alt and new_alt.
1918  *
1919  * To reset a device's configuration (put the device in the ADDRESSED state),
1920  * pass in NULL for new_config, cur_alt, and new_alt.
1921  *
1922  * To change alternate interface settings, pass in NULL for new_config,
1923  * pass in the current alternate interface setting in cur_alt,
1924  * and pass in the new alternate interface setting in new_alt.
1925  *
1926  * Return: An error if the requested bandwidth change exceeds the
1927  * bus bandwidth or host controller internal resources.
1928  */
1929 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1930 		struct usb_host_config *new_config,
1931 		struct usb_host_interface *cur_alt,
1932 		struct usb_host_interface *new_alt)
1933 {
1934 	int num_intfs, i, j;
1935 	struct usb_host_interface *alt = NULL;
1936 	int ret = 0;
1937 	struct usb_hcd *hcd;
1938 	struct usb_host_endpoint *ep;
1939 
1940 	hcd = bus_to_hcd(udev->bus);
1941 	if (!hcd->driver->check_bandwidth)
1942 		return 0;
1943 
1944 	/* Configuration is being removed - set configuration 0 */
1945 	if (!new_config && !cur_alt) {
1946 		for (i = 1; i < 16; ++i) {
1947 			ep = udev->ep_out[i];
1948 			if (ep)
1949 				hcd->driver->drop_endpoint(hcd, udev, ep);
1950 			ep = udev->ep_in[i];
1951 			if (ep)
1952 				hcd->driver->drop_endpoint(hcd, udev, ep);
1953 		}
1954 		hcd->driver->check_bandwidth(hcd, udev);
1955 		return 0;
1956 	}
1957 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1958 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1959 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1960 	 * ok to exclude it.
1961 	 */
1962 	if (new_config) {
1963 		num_intfs = new_config->desc.bNumInterfaces;
1964 		/* Remove endpoints (except endpoint 0, which is always on the
1965 		 * schedule) from the old config from the schedule
1966 		 */
1967 		for (i = 1; i < 16; ++i) {
1968 			ep = udev->ep_out[i];
1969 			if (ep) {
1970 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1971 				if (ret < 0)
1972 					goto reset;
1973 			}
1974 			ep = udev->ep_in[i];
1975 			if (ep) {
1976 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1977 				if (ret < 0)
1978 					goto reset;
1979 			}
1980 		}
1981 		for (i = 0; i < num_intfs; ++i) {
1982 			struct usb_host_interface *first_alt;
1983 			int iface_num;
1984 
1985 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1986 			iface_num = first_alt->desc.bInterfaceNumber;
1987 			/* Set up endpoints for alternate interface setting 0 */
1988 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1989 			if (!alt)
1990 				/* No alt setting 0? Pick the first setting. */
1991 				alt = first_alt;
1992 
1993 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1994 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1995 				if (ret < 0)
1996 					goto reset;
1997 			}
1998 		}
1999 	}
2000 	if (cur_alt && new_alt) {
2001 		struct usb_interface *iface = usb_ifnum_to_if(udev,
2002 				cur_alt->desc.bInterfaceNumber);
2003 
2004 		if (!iface)
2005 			return -EINVAL;
2006 		if (iface->resetting_device) {
2007 			/*
2008 			 * The USB core just reset the device, so the xHCI host
2009 			 * and the device will think alt setting 0 is installed.
2010 			 * However, the USB core will pass in the alternate
2011 			 * setting installed before the reset as cur_alt.  Dig
2012 			 * out the alternate setting 0 structure, or the first
2013 			 * alternate setting if a broken device doesn't have alt
2014 			 * setting 0.
2015 			 */
2016 			cur_alt = usb_altnum_to_altsetting(iface, 0);
2017 			if (!cur_alt)
2018 				cur_alt = &iface->altsetting[0];
2019 		}
2020 
2021 		/* Drop all the endpoints in the current alt setting */
2022 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2023 			ret = hcd->driver->drop_endpoint(hcd, udev,
2024 					&cur_alt->endpoint[i]);
2025 			if (ret < 0)
2026 				goto reset;
2027 		}
2028 		/* Add all the endpoints in the new alt setting */
2029 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2030 			ret = hcd->driver->add_endpoint(hcd, udev,
2031 					&new_alt->endpoint[i]);
2032 			if (ret < 0)
2033 				goto reset;
2034 		}
2035 	}
2036 	ret = hcd->driver->check_bandwidth(hcd, udev);
2037 reset:
2038 	if (ret < 0)
2039 		hcd->driver->reset_bandwidth(hcd, udev);
2040 	return ret;
2041 }
2042 
2043 /* Disables the endpoint: synchronizes with the hcd to make sure all
2044  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2045  * have been called previously.  Use for set_configuration, set_interface,
2046  * driver removal, physical disconnect.
2047  *
2048  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2049  * type, maxpacket size, toggle, halt status, and scheduling.
2050  */
2051 void usb_hcd_disable_endpoint(struct usb_device *udev,
2052 		struct usb_host_endpoint *ep)
2053 {
2054 	struct usb_hcd		*hcd;
2055 
2056 	might_sleep();
2057 	hcd = bus_to_hcd(udev->bus);
2058 	if (hcd->driver->endpoint_disable)
2059 		hcd->driver->endpoint_disable(hcd, ep);
2060 }
2061 
2062 /**
2063  * usb_hcd_reset_endpoint - reset host endpoint state
2064  * @udev: USB device.
2065  * @ep:   the endpoint to reset.
2066  *
2067  * Resets any host endpoint state such as the toggle bit, sequence
2068  * number and current window.
2069  */
2070 void usb_hcd_reset_endpoint(struct usb_device *udev,
2071 			    struct usb_host_endpoint *ep)
2072 {
2073 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2074 
2075 	if (hcd->driver->endpoint_reset)
2076 		hcd->driver->endpoint_reset(hcd, ep);
2077 	else {
2078 		int epnum = usb_endpoint_num(&ep->desc);
2079 		int is_out = usb_endpoint_dir_out(&ep->desc);
2080 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2081 
2082 		usb_settoggle(udev, epnum, is_out, 0);
2083 		if (is_control)
2084 			usb_settoggle(udev, epnum, !is_out, 0);
2085 	}
2086 }
2087 
2088 /**
2089  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2090  * @interface:		alternate setting that includes all endpoints.
2091  * @eps:		array of endpoints that need streams.
2092  * @num_eps:		number of endpoints in the array.
2093  * @num_streams:	number of streams to allocate.
2094  * @mem_flags:		flags hcd should use to allocate memory.
2095  *
2096  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2097  * Drivers may queue multiple transfers to different stream IDs, which may
2098  * complete in a different order than they were queued.
2099  *
2100  * Return: On success, the number of allocated streams. On failure, a negative
2101  * error code.
2102  */
2103 int usb_alloc_streams(struct usb_interface *interface,
2104 		struct usb_host_endpoint **eps, unsigned int num_eps,
2105 		unsigned int num_streams, gfp_t mem_flags)
2106 {
2107 	struct usb_hcd *hcd;
2108 	struct usb_device *dev;
2109 	int i, ret;
2110 
2111 	dev = interface_to_usbdev(interface);
2112 	hcd = bus_to_hcd(dev->bus);
2113 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2114 		return -EINVAL;
2115 	if (dev->speed != USB_SPEED_SUPER)
2116 		return -EINVAL;
2117 	if (dev->state < USB_STATE_CONFIGURED)
2118 		return -ENODEV;
2119 
2120 	for (i = 0; i < num_eps; i++) {
2121 		/* Streams only apply to bulk endpoints. */
2122 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2123 			return -EINVAL;
2124 		/* Re-alloc is not allowed */
2125 		if (eps[i]->streams)
2126 			return -EINVAL;
2127 	}
2128 
2129 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2130 			num_streams, mem_flags);
2131 	if (ret < 0)
2132 		return ret;
2133 
2134 	for (i = 0; i < num_eps; i++)
2135 		eps[i]->streams = ret;
2136 
2137 	return ret;
2138 }
2139 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2140 
2141 /**
2142  * usb_free_streams - free bulk endpoint stream IDs.
2143  * @interface:	alternate setting that includes all endpoints.
2144  * @eps:	array of endpoints to remove streams from.
2145  * @num_eps:	number of endpoints in the array.
2146  * @mem_flags:	flags hcd should use to allocate memory.
2147  *
2148  * Reverts a group of bulk endpoints back to not using stream IDs.
2149  * Can fail if we are given bad arguments, or HCD is broken.
2150  *
2151  * Return: 0 on success. On failure, a negative error code.
2152  */
2153 int usb_free_streams(struct usb_interface *interface,
2154 		struct usb_host_endpoint **eps, unsigned int num_eps,
2155 		gfp_t mem_flags)
2156 {
2157 	struct usb_hcd *hcd;
2158 	struct usb_device *dev;
2159 	int i, ret;
2160 
2161 	dev = interface_to_usbdev(interface);
2162 	hcd = bus_to_hcd(dev->bus);
2163 	if (dev->speed != USB_SPEED_SUPER)
2164 		return -EINVAL;
2165 
2166 	/* Double-free is not allowed */
2167 	for (i = 0; i < num_eps; i++)
2168 		if (!eps[i] || !eps[i]->streams)
2169 			return -EINVAL;
2170 
2171 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2172 	if (ret < 0)
2173 		return ret;
2174 
2175 	for (i = 0; i < num_eps; i++)
2176 		eps[i]->streams = 0;
2177 
2178 	return ret;
2179 }
2180 EXPORT_SYMBOL_GPL(usb_free_streams);
2181 
2182 /* Protect against drivers that try to unlink URBs after the device
2183  * is gone, by waiting until all unlinks for @udev are finished.
2184  * Since we don't currently track URBs by device, simply wait until
2185  * nothing is running in the locked region of usb_hcd_unlink_urb().
2186  */
2187 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2188 {
2189 	spin_lock_irq(&hcd_urb_unlink_lock);
2190 	spin_unlock_irq(&hcd_urb_unlink_lock);
2191 }
2192 
2193 /*-------------------------------------------------------------------------*/
2194 
2195 /* called in any context */
2196 int usb_hcd_get_frame_number (struct usb_device *udev)
2197 {
2198 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2199 
2200 	if (!HCD_RH_RUNNING(hcd))
2201 		return -ESHUTDOWN;
2202 	return hcd->driver->get_frame_number (hcd);
2203 }
2204 
2205 /*-------------------------------------------------------------------------*/
2206 
2207 #ifdef	CONFIG_PM
2208 
2209 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2210 {
2211 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2212 	int		status;
2213 	int		old_state = hcd->state;
2214 
2215 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2216 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2217 			rhdev->do_remote_wakeup);
2218 	if (HCD_DEAD(hcd)) {
2219 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2220 		return 0;
2221 	}
2222 
2223 	if (!hcd->driver->bus_suspend) {
2224 		status = -ENOENT;
2225 	} else {
2226 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2227 		hcd->state = HC_STATE_QUIESCING;
2228 		status = hcd->driver->bus_suspend(hcd);
2229 	}
2230 	if (status == 0) {
2231 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2232 		hcd->state = HC_STATE_SUSPENDED;
2233 
2234 		/* Did we race with a root-hub wakeup event? */
2235 		if (rhdev->do_remote_wakeup) {
2236 			char	buffer[6];
2237 
2238 			status = hcd->driver->hub_status_data(hcd, buffer);
2239 			if (status != 0) {
2240 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2241 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2242 				status = -EBUSY;
2243 			}
2244 		}
2245 	} else {
2246 		spin_lock_irq(&hcd_root_hub_lock);
2247 		if (!HCD_DEAD(hcd)) {
2248 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2249 			hcd->state = old_state;
2250 		}
2251 		spin_unlock_irq(&hcd_root_hub_lock);
2252 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2253 				"suspend", status);
2254 	}
2255 	return status;
2256 }
2257 
2258 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2259 {
2260 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2261 	int		status;
2262 	int		old_state = hcd->state;
2263 
2264 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2265 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2266 	if (HCD_DEAD(hcd)) {
2267 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2268 		return 0;
2269 	}
2270 	if (!hcd->driver->bus_resume)
2271 		return -ENOENT;
2272 	if (HCD_RH_RUNNING(hcd))
2273 		return 0;
2274 
2275 	hcd->state = HC_STATE_RESUMING;
2276 	status = hcd->driver->bus_resume(hcd);
2277 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2278 	if (status == 0) {
2279 		struct usb_device *udev;
2280 		int port1;
2281 
2282 		spin_lock_irq(&hcd_root_hub_lock);
2283 		if (!HCD_DEAD(hcd)) {
2284 			usb_set_device_state(rhdev, rhdev->actconfig
2285 					? USB_STATE_CONFIGURED
2286 					: USB_STATE_ADDRESS);
2287 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2288 			hcd->state = HC_STATE_RUNNING;
2289 		}
2290 		spin_unlock_irq(&hcd_root_hub_lock);
2291 
2292 		/*
2293 		 * Check whether any of the enabled ports on the root hub are
2294 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2295 		 * (this is what the USB-2 spec calls a "global resume").
2296 		 * Otherwise we can skip the delay.
2297 		 */
2298 		usb_hub_for_each_child(rhdev, port1, udev) {
2299 			if (udev->state != USB_STATE_NOTATTACHED &&
2300 					!udev->port_is_suspended) {
2301 				usleep_range(10000, 11000);	/* TRSMRCY */
2302 				break;
2303 			}
2304 		}
2305 	} else {
2306 		hcd->state = old_state;
2307 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2308 				"resume", status);
2309 		if (status != -ESHUTDOWN)
2310 			usb_hc_died(hcd);
2311 	}
2312 	return status;
2313 }
2314 
2315 /* Workqueue routine for root-hub remote wakeup */
2316 static void hcd_resume_work(struct work_struct *work)
2317 {
2318 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2319 	struct usb_device *udev = hcd->self.root_hub;
2320 
2321 	usb_remote_wakeup(udev);
2322 }
2323 
2324 /**
2325  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2326  * @hcd: host controller for this root hub
2327  *
2328  * The USB host controller calls this function when its root hub is
2329  * suspended (with the remote wakeup feature enabled) and a remote
2330  * wakeup request is received.  The routine submits a workqueue request
2331  * to resume the root hub (that is, manage its downstream ports again).
2332  */
2333 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2334 {
2335 	unsigned long flags;
2336 
2337 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2338 	if (hcd->rh_registered) {
2339 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2340 		queue_work(pm_wq, &hcd->wakeup_work);
2341 	}
2342 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2343 }
2344 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2345 
2346 #endif	/* CONFIG_PM */
2347 
2348 /*-------------------------------------------------------------------------*/
2349 
2350 #ifdef	CONFIG_USB_OTG
2351 
2352 /**
2353  * usb_bus_start_enum - start immediate enumeration (for OTG)
2354  * @bus: the bus (must use hcd framework)
2355  * @port_num: 1-based number of port; usually bus->otg_port
2356  * Context: in_interrupt()
2357  *
2358  * Starts enumeration, with an immediate reset followed later by
2359  * hub_wq identifying and possibly configuring the device.
2360  * This is needed by OTG controller drivers, where it helps meet
2361  * HNP protocol timing requirements for starting a port reset.
2362  *
2363  * Return: 0 if successful.
2364  */
2365 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2366 {
2367 	struct usb_hcd		*hcd;
2368 	int			status = -EOPNOTSUPP;
2369 
2370 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2371 	 * boards with root hubs hooked up to internal devices (instead of
2372 	 * just the OTG port) may need more attention to resetting...
2373 	 */
2374 	hcd = container_of (bus, struct usb_hcd, self);
2375 	if (port_num && hcd->driver->start_port_reset)
2376 		status = hcd->driver->start_port_reset(hcd, port_num);
2377 
2378 	/* allocate hub_wq shortly after (first) root port reset finishes;
2379 	 * it may issue others, until at least 50 msecs have passed.
2380 	 */
2381 	if (status == 0)
2382 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2383 	return status;
2384 }
2385 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2386 
2387 #endif
2388 
2389 /*-------------------------------------------------------------------------*/
2390 
2391 /**
2392  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2393  * @irq: the IRQ being raised
2394  * @__hcd: pointer to the HCD whose IRQ is being signaled
2395  *
2396  * If the controller isn't HALTed, calls the driver's irq handler.
2397  * Checks whether the controller is now dead.
2398  *
2399  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2400  */
2401 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2402 {
2403 	struct usb_hcd		*hcd = __hcd;
2404 	irqreturn_t		rc;
2405 
2406 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2407 		rc = IRQ_NONE;
2408 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2409 		rc = IRQ_NONE;
2410 	else
2411 		rc = IRQ_HANDLED;
2412 
2413 	return rc;
2414 }
2415 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2416 
2417 /*-------------------------------------------------------------------------*/
2418 
2419 /**
2420  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2421  * @hcd: pointer to the HCD representing the controller
2422  *
2423  * This is called by bus glue to report a USB host controller that died
2424  * while operations may still have been pending.  It's called automatically
2425  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2426  *
2427  * Only call this function with the primary HCD.
2428  */
2429 void usb_hc_died (struct usb_hcd *hcd)
2430 {
2431 	unsigned long flags;
2432 
2433 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2434 
2435 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2436 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2437 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2438 	if (hcd->rh_registered) {
2439 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2440 
2441 		/* make hub_wq clean up old urbs and devices */
2442 		usb_set_device_state (hcd->self.root_hub,
2443 				USB_STATE_NOTATTACHED);
2444 		usb_kick_hub_wq(hcd->self.root_hub);
2445 	}
2446 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2447 		hcd = hcd->shared_hcd;
2448 		if (hcd->rh_registered) {
2449 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2450 
2451 			/* make hub_wq clean up old urbs and devices */
2452 			usb_set_device_state(hcd->self.root_hub,
2453 					USB_STATE_NOTATTACHED);
2454 			usb_kick_hub_wq(hcd->self.root_hub);
2455 		}
2456 	}
2457 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2458 	/* Make sure that the other roothub is also deallocated. */
2459 }
2460 EXPORT_SYMBOL_GPL (usb_hc_died);
2461 
2462 /*-------------------------------------------------------------------------*/
2463 
2464 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2465 {
2466 
2467 	spin_lock_init(&bh->lock);
2468 	INIT_LIST_HEAD(&bh->head);
2469 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2470 }
2471 
2472 /**
2473  * usb_create_shared_hcd - create and initialize an HCD structure
2474  * @driver: HC driver that will use this hcd
2475  * @dev: device for this HC, stored in hcd->self.controller
2476  * @bus_name: value to store in hcd->self.bus_name
2477  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2478  *              PCI device.  Only allocate certain resources for the primary HCD
2479  * Context: !in_interrupt()
2480  *
2481  * Allocate a struct usb_hcd, with extra space at the end for the
2482  * HC driver's private data.  Initialize the generic members of the
2483  * hcd structure.
2484  *
2485  * Return: On success, a pointer to the created and initialized HCD structure.
2486  * On failure (e.g. if memory is unavailable), %NULL.
2487  */
2488 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2489 		struct device *dev, const char *bus_name,
2490 		struct usb_hcd *primary_hcd)
2491 {
2492 	struct usb_hcd *hcd;
2493 
2494 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2495 	if (!hcd) {
2496 		dev_dbg (dev, "hcd alloc failed\n");
2497 		return NULL;
2498 	}
2499 	if (primary_hcd == NULL) {
2500 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2501 				GFP_KERNEL);
2502 		if (!hcd->bandwidth_mutex) {
2503 			kfree(hcd);
2504 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2505 			return NULL;
2506 		}
2507 		mutex_init(hcd->bandwidth_mutex);
2508 		dev_set_drvdata(dev, hcd);
2509 	} else {
2510 		mutex_lock(&usb_port_peer_mutex);
2511 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2512 		hcd->primary_hcd = primary_hcd;
2513 		primary_hcd->primary_hcd = primary_hcd;
2514 		hcd->shared_hcd = primary_hcd;
2515 		primary_hcd->shared_hcd = hcd;
2516 		mutex_unlock(&usb_port_peer_mutex);
2517 	}
2518 
2519 	kref_init(&hcd->kref);
2520 
2521 	usb_bus_init(&hcd->self);
2522 	hcd->self.controller = dev;
2523 	hcd->self.bus_name = bus_name;
2524 	hcd->self.uses_dma = (dev->dma_mask != NULL);
2525 
2526 	init_timer(&hcd->rh_timer);
2527 	hcd->rh_timer.function = rh_timer_func;
2528 	hcd->rh_timer.data = (unsigned long) hcd;
2529 #ifdef CONFIG_PM
2530 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2531 #endif
2532 
2533 	hcd->driver = driver;
2534 	hcd->speed = driver->flags & HCD_MASK;
2535 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2536 			"USB Host Controller";
2537 	return hcd;
2538 }
2539 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2540 
2541 /**
2542  * usb_create_hcd - create and initialize an HCD structure
2543  * @driver: HC driver that will use this hcd
2544  * @dev: device for this HC, stored in hcd->self.controller
2545  * @bus_name: value to store in hcd->self.bus_name
2546  * Context: !in_interrupt()
2547  *
2548  * Allocate a struct usb_hcd, with extra space at the end for the
2549  * HC driver's private data.  Initialize the generic members of the
2550  * hcd structure.
2551  *
2552  * Return: On success, a pointer to the created and initialized HCD
2553  * structure. On failure (e.g. if memory is unavailable), %NULL.
2554  */
2555 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2556 		struct device *dev, const char *bus_name)
2557 {
2558 	return usb_create_shared_hcd(driver, dev, bus_name, NULL);
2559 }
2560 EXPORT_SYMBOL_GPL(usb_create_hcd);
2561 
2562 /*
2563  * Roothubs that share one PCI device must also share the bandwidth mutex.
2564  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2565  * deallocated.
2566  *
2567  * Make sure to only deallocate the bandwidth_mutex when the primary HCD is
2568  * freed.  When hcd_release() is called for either hcd in a peer set
2569  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers to
2570  * block new peering attempts
2571  */
2572 static void hcd_release(struct kref *kref)
2573 {
2574 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2575 
2576 	mutex_lock(&usb_port_peer_mutex);
2577 	if (usb_hcd_is_primary_hcd(hcd))
2578 		kfree(hcd->bandwidth_mutex);
2579 	if (hcd->shared_hcd) {
2580 		struct usb_hcd *peer = hcd->shared_hcd;
2581 
2582 		peer->shared_hcd = NULL;
2583 		if (peer->primary_hcd == hcd)
2584 			peer->primary_hcd = NULL;
2585 	}
2586 	mutex_unlock(&usb_port_peer_mutex);
2587 	kfree(hcd);
2588 }
2589 
2590 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2591 {
2592 	if (hcd)
2593 		kref_get (&hcd->kref);
2594 	return hcd;
2595 }
2596 EXPORT_SYMBOL_GPL(usb_get_hcd);
2597 
2598 void usb_put_hcd (struct usb_hcd *hcd)
2599 {
2600 	if (hcd)
2601 		kref_put (&hcd->kref, hcd_release);
2602 }
2603 EXPORT_SYMBOL_GPL(usb_put_hcd);
2604 
2605 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2606 {
2607 	if (!hcd->primary_hcd)
2608 		return 1;
2609 	return hcd == hcd->primary_hcd;
2610 }
2611 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2612 
2613 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2614 {
2615 	if (!hcd->driver->find_raw_port_number)
2616 		return port1;
2617 
2618 	return hcd->driver->find_raw_port_number(hcd, port1);
2619 }
2620 
2621 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2622 		unsigned int irqnum, unsigned long irqflags)
2623 {
2624 	int retval;
2625 
2626 	if (hcd->driver->irq) {
2627 
2628 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2629 				hcd->driver->description, hcd->self.busnum);
2630 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2631 				hcd->irq_descr, hcd);
2632 		if (retval != 0) {
2633 			dev_err(hcd->self.controller,
2634 					"request interrupt %d failed\n",
2635 					irqnum);
2636 			return retval;
2637 		}
2638 		hcd->irq = irqnum;
2639 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2640 				(hcd->driver->flags & HCD_MEMORY) ?
2641 					"io mem" : "io base",
2642 					(unsigned long long)hcd->rsrc_start);
2643 	} else {
2644 		hcd->irq = 0;
2645 		if (hcd->rsrc_start)
2646 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2647 					(hcd->driver->flags & HCD_MEMORY) ?
2648 					"io mem" : "io base",
2649 					(unsigned long long)hcd->rsrc_start);
2650 	}
2651 	return 0;
2652 }
2653 
2654 /*
2655  * Before we free this root hub, flush in-flight peering attempts
2656  * and disable peer lookups
2657  */
2658 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2659 {
2660 	struct usb_device *rhdev;
2661 
2662 	mutex_lock(&usb_port_peer_mutex);
2663 	rhdev = hcd->self.root_hub;
2664 	hcd->self.root_hub = NULL;
2665 	mutex_unlock(&usb_port_peer_mutex);
2666 	usb_put_dev(rhdev);
2667 }
2668 
2669 /**
2670  * usb_add_hcd - finish generic HCD structure initialization and register
2671  * @hcd: the usb_hcd structure to initialize
2672  * @irqnum: Interrupt line to allocate
2673  * @irqflags: Interrupt type flags
2674  *
2675  * Finish the remaining parts of generic HCD initialization: allocate the
2676  * buffers of consistent memory, register the bus, request the IRQ line,
2677  * and call the driver's reset() and start() routines.
2678  */
2679 int usb_add_hcd(struct usb_hcd *hcd,
2680 		unsigned int irqnum, unsigned long irqflags)
2681 {
2682 	int retval;
2683 	struct usb_device *rhdev;
2684 
2685 	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
2686 		struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
2687 
2688 		if (IS_ERR(phy)) {
2689 			retval = PTR_ERR(phy);
2690 			if (retval == -EPROBE_DEFER)
2691 				return retval;
2692 		} else {
2693 			retval = usb_phy_init(phy);
2694 			if (retval) {
2695 				usb_put_phy(phy);
2696 				return retval;
2697 			}
2698 			hcd->usb_phy = phy;
2699 			hcd->remove_phy = 1;
2700 		}
2701 	}
2702 
2703 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) {
2704 		struct phy *phy = phy_get(hcd->self.controller, "usb");
2705 
2706 		if (IS_ERR(phy)) {
2707 			retval = PTR_ERR(phy);
2708 			if (retval == -EPROBE_DEFER)
2709 				goto err_phy;
2710 		} else {
2711 			retval = phy_init(phy);
2712 			if (retval) {
2713 				phy_put(phy);
2714 				goto err_phy;
2715 			}
2716 			retval = phy_power_on(phy);
2717 			if (retval) {
2718 				phy_exit(phy);
2719 				phy_put(phy);
2720 				goto err_phy;
2721 			}
2722 			hcd->phy = phy;
2723 			hcd->remove_phy = 1;
2724 		}
2725 	}
2726 
2727 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2728 
2729 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2730 	if (authorized_default < 0 || authorized_default > 1) {
2731 		if (hcd->wireless)
2732 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2733 		else
2734 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2735 	} else {
2736 		if (authorized_default)
2737 			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2738 		else
2739 			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2740 	}
2741 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2742 
2743 	/* per default all interfaces are authorized */
2744 	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2745 
2746 	/* HC is in reset state, but accessible.  Now do the one-time init,
2747 	 * bottom up so that hcds can customize the root hubs before hub_wq
2748 	 * starts talking to them.  (Note, bus id is assigned early too.)
2749 	 */
2750 	retval = hcd_buffer_create(hcd);
2751 	if (retval != 0) {
2752 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
2753 		goto err_create_buf;
2754 	}
2755 
2756 	retval = usb_register_bus(&hcd->self);
2757 	if (retval < 0)
2758 		goto err_register_bus;
2759 
2760 	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2761 	if (rhdev == NULL) {
2762 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
2763 		retval = -ENOMEM;
2764 		goto err_allocate_root_hub;
2765 	}
2766 	mutex_lock(&usb_port_peer_mutex);
2767 	hcd->self.root_hub = rhdev;
2768 	mutex_unlock(&usb_port_peer_mutex);
2769 
2770 	switch (hcd->speed) {
2771 	case HCD_USB11:
2772 		rhdev->speed = USB_SPEED_FULL;
2773 		break;
2774 	case HCD_USB2:
2775 		rhdev->speed = USB_SPEED_HIGH;
2776 		break;
2777 	case HCD_USB25:
2778 		rhdev->speed = USB_SPEED_WIRELESS;
2779 		break;
2780 	case HCD_USB3:
2781 	case HCD_USB31:
2782 		rhdev->speed = USB_SPEED_SUPER;
2783 		break;
2784 	default:
2785 		retval = -EINVAL;
2786 		goto err_set_rh_speed;
2787 	}
2788 
2789 	/* wakeup flag init defaults to "everything works" for root hubs,
2790 	 * but drivers can override it in reset() if needed, along with
2791 	 * recording the overall controller's system wakeup capability.
2792 	 */
2793 	device_set_wakeup_capable(&rhdev->dev, 1);
2794 
2795 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2796 	 * registered.  But since the controller can die at any time,
2797 	 * let's initialize the flag before touching the hardware.
2798 	 */
2799 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2800 
2801 	/* "reset" is misnamed; its role is now one-time init. the controller
2802 	 * should already have been reset (and boot firmware kicked off etc).
2803 	 */
2804 	if (hcd->driver->reset) {
2805 		retval = hcd->driver->reset(hcd);
2806 		if (retval < 0) {
2807 			dev_err(hcd->self.controller, "can't setup: %d\n",
2808 					retval);
2809 			goto err_hcd_driver_setup;
2810 		}
2811 	}
2812 	hcd->rh_pollable = 1;
2813 
2814 	/* NOTE: root hub and controller capabilities may not be the same */
2815 	if (device_can_wakeup(hcd->self.controller)
2816 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2817 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2818 
2819 	/* initialize tasklets */
2820 	init_giveback_urb_bh(&hcd->high_prio_bh);
2821 	init_giveback_urb_bh(&hcd->low_prio_bh);
2822 
2823 	/* enable irqs just before we start the controller,
2824 	 * if the BIOS provides legacy PCI irqs.
2825 	 */
2826 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2827 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2828 		if (retval)
2829 			goto err_request_irq;
2830 	}
2831 
2832 	hcd->state = HC_STATE_RUNNING;
2833 	retval = hcd->driver->start(hcd);
2834 	if (retval < 0) {
2835 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2836 		goto err_hcd_driver_start;
2837 	}
2838 
2839 	/* starting here, usbcore will pay attention to this root hub */
2840 	retval = register_root_hub(hcd);
2841 	if (retval != 0)
2842 		goto err_register_root_hub;
2843 
2844 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2845 	if (retval < 0) {
2846 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2847 		       retval);
2848 		goto error_create_attr_group;
2849 	}
2850 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2851 		usb_hcd_poll_rh_status(hcd);
2852 
2853 	return retval;
2854 
2855 error_create_attr_group:
2856 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2857 	if (HC_IS_RUNNING(hcd->state))
2858 		hcd->state = HC_STATE_QUIESCING;
2859 	spin_lock_irq(&hcd_root_hub_lock);
2860 	hcd->rh_registered = 0;
2861 	spin_unlock_irq(&hcd_root_hub_lock);
2862 
2863 #ifdef CONFIG_PM
2864 	cancel_work_sync(&hcd->wakeup_work);
2865 #endif
2866 	mutex_lock(&usb_bus_list_lock);
2867 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2868 	mutex_unlock(&usb_bus_list_lock);
2869 err_register_root_hub:
2870 	hcd->rh_pollable = 0;
2871 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2872 	del_timer_sync(&hcd->rh_timer);
2873 	hcd->driver->stop(hcd);
2874 	hcd->state = HC_STATE_HALT;
2875 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2876 	del_timer_sync(&hcd->rh_timer);
2877 err_hcd_driver_start:
2878 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2879 		free_irq(irqnum, hcd);
2880 err_request_irq:
2881 err_hcd_driver_setup:
2882 err_set_rh_speed:
2883 	usb_put_invalidate_rhdev(hcd);
2884 err_allocate_root_hub:
2885 	usb_deregister_bus(&hcd->self);
2886 err_register_bus:
2887 	hcd_buffer_destroy(hcd);
2888 err_create_buf:
2889 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2890 		phy_power_off(hcd->phy);
2891 		phy_exit(hcd->phy);
2892 		phy_put(hcd->phy);
2893 		hcd->phy = NULL;
2894 	}
2895 err_phy:
2896 	if (hcd->remove_phy && hcd->usb_phy) {
2897 		usb_phy_shutdown(hcd->usb_phy);
2898 		usb_put_phy(hcd->usb_phy);
2899 		hcd->usb_phy = NULL;
2900 	}
2901 	return retval;
2902 }
2903 EXPORT_SYMBOL_GPL(usb_add_hcd);
2904 
2905 /**
2906  * usb_remove_hcd - shutdown processing for generic HCDs
2907  * @hcd: the usb_hcd structure to remove
2908  * Context: !in_interrupt()
2909  *
2910  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2911  * invoking the HCD's stop() method.
2912  */
2913 void usb_remove_hcd(struct usb_hcd *hcd)
2914 {
2915 	struct usb_device *rhdev = hcd->self.root_hub;
2916 
2917 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2918 
2919 	usb_get_dev(rhdev);
2920 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2921 
2922 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2923 	if (HC_IS_RUNNING (hcd->state))
2924 		hcd->state = HC_STATE_QUIESCING;
2925 
2926 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2927 	spin_lock_irq (&hcd_root_hub_lock);
2928 	hcd->rh_registered = 0;
2929 	spin_unlock_irq (&hcd_root_hub_lock);
2930 
2931 #ifdef CONFIG_PM
2932 	cancel_work_sync(&hcd->wakeup_work);
2933 #endif
2934 
2935 	mutex_lock(&usb_bus_list_lock);
2936 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2937 	mutex_unlock(&usb_bus_list_lock);
2938 
2939 	/*
2940 	 * tasklet_kill() isn't needed here because:
2941 	 * - driver's disconnect() called from usb_disconnect() should
2942 	 *   make sure its URBs are completed during the disconnect()
2943 	 *   callback
2944 	 *
2945 	 * - it is too late to run complete() here since driver may have
2946 	 *   been removed already now
2947 	 */
2948 
2949 	/* Prevent any more root-hub status calls from the timer.
2950 	 * The HCD might still restart the timer (if a port status change
2951 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2952 	 * the hub_status_data() callback.
2953 	 */
2954 	hcd->rh_pollable = 0;
2955 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2956 	del_timer_sync(&hcd->rh_timer);
2957 
2958 	hcd->driver->stop(hcd);
2959 	hcd->state = HC_STATE_HALT;
2960 
2961 	/* In case the HCD restarted the timer, stop it again. */
2962 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2963 	del_timer_sync(&hcd->rh_timer);
2964 
2965 	if (usb_hcd_is_primary_hcd(hcd)) {
2966 		if (hcd->irq > 0)
2967 			free_irq(hcd->irq, hcd);
2968 	}
2969 
2970 	usb_deregister_bus(&hcd->self);
2971 	hcd_buffer_destroy(hcd);
2972 
2973 	if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2974 		phy_power_off(hcd->phy);
2975 		phy_exit(hcd->phy);
2976 		phy_put(hcd->phy);
2977 		hcd->phy = NULL;
2978 	}
2979 	if (hcd->remove_phy && hcd->usb_phy) {
2980 		usb_phy_shutdown(hcd->usb_phy);
2981 		usb_put_phy(hcd->usb_phy);
2982 		hcd->usb_phy = NULL;
2983 	}
2984 
2985 	usb_put_invalidate_rhdev(hcd);
2986 }
2987 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2988 
2989 void
2990 usb_hcd_platform_shutdown(struct platform_device *dev)
2991 {
2992 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2993 
2994 	if (hcd->driver->shutdown)
2995 		hcd->driver->shutdown(hcd);
2996 }
2997 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2998 
2999 /*-------------------------------------------------------------------------*/
3000 
3001 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
3002 
3003 const struct usb_mon_operations *mon_ops;
3004 
3005 /*
3006  * The registration is unlocked.
3007  * We do it this way because we do not want to lock in hot paths.
3008  *
3009  * Notice that the code is minimally error-proof. Because usbmon needs
3010  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3011  */
3012 
3013 int usb_mon_register(const struct usb_mon_operations *ops)
3014 {
3015 
3016 	if (mon_ops)
3017 		return -EBUSY;
3018 
3019 	mon_ops = ops;
3020 	mb();
3021 	return 0;
3022 }
3023 EXPORT_SYMBOL_GPL (usb_mon_register);
3024 
3025 void usb_mon_deregister (void)
3026 {
3027 
3028 	if (mon_ops == NULL) {
3029 		printk(KERN_ERR "USB: monitor was not registered\n");
3030 		return;
3031 	}
3032 	mon_ops = NULL;
3033 	mb();
3034 }
3035 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3036 
3037 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3038