xref: /linux/drivers/usb/core/hcd.c (revision e190bfe56841551b1ad5abb42ebd0c4798cc8c01)
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/module.h>
26 #include <linux/version.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/completion.h>
30 #include <linux/utsname.h>
31 #include <linux/mm.h>
32 #include <asm/io.h>
33 #include <linux/device.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/mutex.h>
36 #include <asm/irq.h>
37 #include <asm/byteorder.h>
38 #include <asm/unaligned.h>
39 #include <linux/platform_device.h>
40 #include <linux/workqueue.h>
41 #include <linux/pm_runtime.h>
42 
43 #include <linux/usb.h>
44 #include <linux/usb/hcd.h>
45 
46 #include "usb.h"
47 
48 
49 /*-------------------------------------------------------------------------*/
50 
51 /*
52  * USB Host Controller Driver framework
53  *
54  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
55  * HCD-specific behaviors/bugs.
56  *
57  * This does error checks, tracks devices and urbs, and delegates to a
58  * "hc_driver" only for code (and data) that really needs to know about
59  * hardware differences.  That includes root hub registers, i/o queues,
60  * and so on ... but as little else as possible.
61  *
62  * Shared code includes most of the "root hub" code (these are emulated,
63  * though each HC's hardware works differently) and PCI glue, plus request
64  * tracking overhead.  The HCD code should only block on spinlocks or on
65  * hardware handshaking; blocking on software events (such as other kernel
66  * threads releasing resources, or completing actions) is all generic.
67  *
68  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
69  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
70  * only by the hub driver ... and that neither should be seen or used by
71  * usb client device drivers.
72  *
73  * Contributors of ideas or unattributed patches include: David Brownell,
74  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
75  *
76  * HISTORY:
77  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
78  *		associated cleanup.  "usb_hcd" still != "usb_bus".
79  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
80  */
81 
82 /*-------------------------------------------------------------------------*/
83 
84 /* Keep track of which host controller drivers are loaded */
85 unsigned long usb_hcds_loaded;
86 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
87 
88 /* host controllers we manage */
89 LIST_HEAD (usb_bus_list);
90 EXPORT_SYMBOL_GPL (usb_bus_list);
91 
92 /* used when allocating bus numbers */
93 #define USB_MAXBUS		64
94 struct usb_busmap {
95 	unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
96 };
97 static struct usb_busmap busmap;
98 
99 /* used when updating list of hcds */
100 DEFINE_MUTEX(usb_bus_list_lock);	/* exported only for usbfs */
101 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
102 
103 /* used for controlling access to virtual root hubs */
104 static DEFINE_SPINLOCK(hcd_root_hub_lock);
105 
106 /* used when updating an endpoint's URB list */
107 static DEFINE_SPINLOCK(hcd_urb_list_lock);
108 
109 /* used to protect against unlinking URBs after the device is gone */
110 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
111 
112 /* wait queue for synchronous unlinks */
113 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
114 
115 static inline int is_root_hub(struct usb_device *udev)
116 {
117 	return (udev->parent == NULL);
118 }
119 
120 /*-------------------------------------------------------------------------*/
121 
122 /*
123  * Sharable chunks of root hub code.
124  */
125 
126 /*-------------------------------------------------------------------------*/
127 
128 #define KERNEL_REL	((LINUX_VERSION_CODE >> 16) & 0x0ff)
129 #define KERNEL_VER	((LINUX_VERSION_CODE >> 8) & 0x0ff)
130 
131 /* usb 3.0 root hub device descriptor */
132 static const u8 usb3_rh_dev_descriptor[18] = {
133 	0x12,       /*  __u8  bLength; */
134 	0x01,       /*  __u8  bDescriptorType; Device */
135 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
136 
137 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
138 	0x00,	    /*  __u8  bDeviceSubClass; */
139 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
140 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
141 
142 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
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 2.0 root hub device descriptor */
153 static const u8 usb2_rh_dev_descriptor [18] = {
154 	0x12,       /*  __u8  bLength; */
155 	0x01,       /*  __u8  bDescriptorType; Device */
156 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
157 
158 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
159 	0x00,	    /*  __u8  bDeviceSubClass; */
160 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
161 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
162 
163 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
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 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
174 
175 /* usb 1.1 root hub device descriptor */
176 static const u8 usb11_rh_dev_descriptor [18] = {
177 	0x12,       /*  __u8  bLength; */
178 	0x01,       /*  __u8  bDescriptorType; Device */
179 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
180 
181 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
182 	0x00,	    /*  __u8  bDeviceSubClass; */
183 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
184 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
185 
186 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
187 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
188 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
189 
190 	0x03,       /*  __u8  iManufacturer; */
191 	0x02,       /*  __u8  iProduct; */
192 	0x01,       /*  __u8  iSerialNumber; */
193 	0x01        /*  __u8  bNumConfigurations; */
194 };
195 
196 
197 /*-------------------------------------------------------------------------*/
198 
199 /* Configuration descriptors for our root hubs */
200 
201 static const u8 fs_rh_config_descriptor [] = {
202 
203 	/* one configuration */
204 	0x09,       /*  __u8  bLength; */
205 	0x02,       /*  __u8  bDescriptorType; Configuration */
206 	0x19, 0x00, /*  __le16 wTotalLength; */
207 	0x01,       /*  __u8  bNumInterfaces; (1) */
208 	0x01,       /*  __u8  bConfigurationValue; */
209 	0x00,       /*  __u8  iConfiguration; */
210 	0xc0,       /*  __u8  bmAttributes;
211 				 Bit 7: must be set,
212 				     6: Self-powered,
213 				     5: Remote wakeup,
214 				     4..0: resvd */
215 	0x00,       /*  __u8  MaxPower; */
216 
217 	/* USB 1.1:
218 	 * USB 2.0, single TT organization (mandatory):
219 	 *	one interface, protocol 0
220 	 *
221 	 * USB 2.0, multiple TT organization (optional):
222 	 *	two interfaces, protocols 1 (like single TT)
223 	 *	and 2 (multiple TT mode) ... config is
224 	 *	sometimes settable
225 	 *	NOT IMPLEMENTED
226 	 */
227 
228 	/* one interface */
229 	0x09,       /*  __u8  if_bLength; */
230 	0x04,       /*  __u8  if_bDescriptorType; Interface */
231 	0x00,       /*  __u8  if_bInterfaceNumber; */
232 	0x00,       /*  __u8  if_bAlternateSetting; */
233 	0x01,       /*  __u8  if_bNumEndpoints; */
234 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
235 	0x00,       /*  __u8  if_bInterfaceSubClass; */
236 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
237 	0x00,       /*  __u8  if_iInterface; */
238 
239 	/* one endpoint (status change endpoint) */
240 	0x07,       /*  __u8  ep_bLength; */
241 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
242 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
243  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
244  	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
245 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
246 };
247 
248 static const u8 hs_rh_config_descriptor [] = {
249 
250 	/* one configuration */
251 	0x09,       /*  __u8  bLength; */
252 	0x02,       /*  __u8  bDescriptorType; Configuration */
253 	0x19, 0x00, /*  __le16 wTotalLength; */
254 	0x01,       /*  __u8  bNumInterfaces; (1) */
255 	0x01,       /*  __u8  bConfigurationValue; */
256 	0x00,       /*  __u8  iConfiguration; */
257 	0xc0,       /*  __u8  bmAttributes;
258 				 Bit 7: must be set,
259 				     6: Self-powered,
260 				     5: Remote wakeup,
261 				     4..0: resvd */
262 	0x00,       /*  __u8  MaxPower; */
263 
264 	/* USB 1.1:
265 	 * USB 2.0, single TT organization (mandatory):
266 	 *	one interface, protocol 0
267 	 *
268 	 * USB 2.0, multiple TT organization (optional):
269 	 *	two interfaces, protocols 1 (like single TT)
270 	 *	and 2 (multiple TT mode) ... config is
271 	 *	sometimes settable
272 	 *	NOT IMPLEMENTED
273 	 */
274 
275 	/* one interface */
276 	0x09,       /*  __u8  if_bLength; */
277 	0x04,       /*  __u8  if_bDescriptorType; Interface */
278 	0x00,       /*  __u8  if_bInterfaceNumber; */
279 	0x00,       /*  __u8  if_bAlternateSetting; */
280 	0x01,       /*  __u8  if_bNumEndpoints; */
281 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
282 	0x00,       /*  __u8  if_bInterfaceSubClass; */
283 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
284 	0x00,       /*  __u8  if_iInterface; */
285 
286 	/* one endpoint (status change endpoint) */
287 	0x07,       /*  __u8  ep_bLength; */
288 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
289 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
290  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
291 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
292 		     * see hub.c:hub_configure() for details. */
293 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
294 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
295 };
296 
297 static const u8 ss_rh_config_descriptor[] = {
298 	/* one configuration */
299 	0x09,       /*  __u8  bLength; */
300 	0x02,       /*  __u8  bDescriptorType; Configuration */
301 	0x19, 0x00, /*  __le16 wTotalLength; FIXME */
302 	0x01,       /*  __u8  bNumInterfaces; (1) */
303 	0x01,       /*  __u8  bConfigurationValue; */
304 	0x00,       /*  __u8  iConfiguration; */
305 	0xc0,       /*  __u8  bmAttributes;
306 				 Bit 7: must be set,
307 				     6: Self-powered,
308 				     5: Remote wakeup,
309 				     4..0: resvd */
310 	0x00,       /*  __u8  MaxPower; */
311 
312 	/* one interface */
313 	0x09,       /*  __u8  if_bLength; */
314 	0x04,       /*  __u8  if_bDescriptorType; Interface */
315 	0x00,       /*  __u8  if_bInterfaceNumber; */
316 	0x00,       /*  __u8  if_bAlternateSetting; */
317 	0x01,       /*  __u8  if_bNumEndpoints; */
318 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
319 	0x00,       /*  __u8  if_bInterfaceSubClass; */
320 	0x00,       /*  __u8  if_bInterfaceProtocol; */
321 	0x00,       /*  __u8  if_iInterface; */
322 
323 	/* one endpoint (status change endpoint) */
324 	0x07,       /*  __u8  ep_bLength; */
325 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
326 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
327 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
328 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
329 		     * see hub.c:hub_configure() for details. */
330 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
331 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
332 	/*
333 	 * All 3.0 hubs should have an endpoint companion descriptor,
334 	 * but we're ignoring that for now.  FIXME?
335 	 */
336 };
337 
338 /*-------------------------------------------------------------------------*/
339 
340 /**
341  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
342  * @s: Null-terminated ASCII (actually ISO-8859-1) string
343  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
344  * @len: Length (in bytes; may be odd) of descriptor buffer.
345  *
346  * The return value is the number of bytes filled in: 2 + 2*strlen(s) or
347  * buflen, whichever is less.
348  *
349  * USB String descriptors can contain at most 126 characters; input
350  * strings longer than that are truncated.
351  */
352 static unsigned
353 ascii2desc(char const *s, u8 *buf, unsigned len)
354 {
355 	unsigned n, t = 2 + 2*strlen(s);
356 
357 	if (t > 254)
358 		t = 254;	/* Longest possible UTF string descriptor */
359 	if (len > t)
360 		len = t;
361 
362 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
363 
364 	n = len;
365 	while (n--) {
366 		*buf++ = t;
367 		if (!n--)
368 			break;
369 		*buf++ = t >> 8;
370 		t = (unsigned char)*s++;
371 	}
372 	return len;
373 }
374 
375 /**
376  * rh_string() - provides string descriptors for root hub
377  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
378  * @hcd: the host controller for this root hub
379  * @data: buffer for output packet
380  * @len: length of the provided buffer
381  *
382  * Produces either a manufacturer, product or serial number string for the
383  * virtual root hub device.
384  * Returns the number of bytes filled in: the length of the descriptor or
385  * of the provided buffer, whichever is less.
386  */
387 static unsigned
388 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
389 {
390 	char buf[100];
391 	char const *s;
392 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
393 
394 	// language ids
395 	switch (id) {
396 	case 0:
397 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
398 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
399 		if (len > 4)
400 			len = 4;
401 		memcpy(data, langids, len);
402 		return len;
403 	case 1:
404 		/* Serial number */
405 		s = hcd->self.bus_name;
406 		break;
407 	case 2:
408 		/* Product name */
409 		s = hcd->product_desc;
410 		break;
411 	case 3:
412 		/* Manufacturer */
413 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
414 			init_utsname()->release, hcd->driver->description);
415 		s = buf;
416 		break;
417 	default:
418 		/* Can't happen; caller guarantees it */
419 		return 0;
420 	}
421 
422 	return ascii2desc(s, data, len);
423 }
424 
425 
426 /* Root hub control transfers execute synchronously */
427 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
428 {
429 	struct usb_ctrlrequest *cmd;
430  	u16		typeReq, wValue, wIndex, wLength;
431 	u8		*ubuf = urb->transfer_buffer;
432 	u8		tbuf [sizeof (struct usb_hub_descriptor)]
433 		__attribute__((aligned(4)));
434 	const u8	*bufp = tbuf;
435 	unsigned	len = 0;
436 	int		status;
437 	u8		patch_wakeup = 0;
438 	u8		patch_protocol = 0;
439 
440 	might_sleep();
441 
442 	spin_lock_irq(&hcd_root_hub_lock);
443 	status = usb_hcd_link_urb_to_ep(hcd, urb);
444 	spin_unlock_irq(&hcd_root_hub_lock);
445 	if (status)
446 		return status;
447 	urb->hcpriv = hcd;	/* Indicate it's queued */
448 
449 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
450 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
451 	wValue   = le16_to_cpu (cmd->wValue);
452 	wIndex   = le16_to_cpu (cmd->wIndex);
453 	wLength  = le16_to_cpu (cmd->wLength);
454 
455 	if (wLength > urb->transfer_buffer_length)
456 		goto error;
457 
458 	urb->actual_length = 0;
459 	switch (typeReq) {
460 
461 	/* DEVICE REQUESTS */
462 
463 	/* The root hub's remote wakeup enable bit is implemented using
464 	 * driver model wakeup flags.  If this system supports wakeup
465 	 * through USB, userspace may change the default "allow wakeup"
466 	 * policy through sysfs or these calls.
467 	 *
468 	 * Most root hubs support wakeup from downstream devices, for
469 	 * runtime power management (disabling USB clocks and reducing
470 	 * VBUS power usage).  However, not all of them do so; silicon,
471 	 * board, and BIOS bugs here are not uncommon, so these can't
472 	 * be treated quite like external hubs.
473 	 *
474 	 * Likewise, not all root hubs will pass wakeup events upstream,
475 	 * to wake up the whole system.  So don't assume root hub and
476 	 * controller capabilities are identical.
477 	 */
478 
479 	case DeviceRequest | USB_REQ_GET_STATUS:
480 		tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
481 					<< USB_DEVICE_REMOTE_WAKEUP)
482 				| (1 << USB_DEVICE_SELF_POWERED);
483 		tbuf [1] = 0;
484 		len = 2;
485 		break;
486 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
487 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
488 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
489 		else
490 			goto error;
491 		break;
492 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
493 		if (device_can_wakeup(&hcd->self.root_hub->dev)
494 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
495 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
496 		else
497 			goto error;
498 		break;
499 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
500 		tbuf [0] = 1;
501 		len = 1;
502 			/* FALLTHROUGH */
503 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
504 		break;
505 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
506 		switch (wValue & 0xff00) {
507 		case USB_DT_DEVICE << 8:
508 			switch (hcd->driver->flags & HCD_MASK) {
509 			case HCD_USB3:
510 				bufp = usb3_rh_dev_descriptor;
511 				break;
512 			case HCD_USB2:
513 				bufp = usb2_rh_dev_descriptor;
514 				break;
515 			case HCD_USB11:
516 				bufp = usb11_rh_dev_descriptor;
517 				break;
518 			default:
519 				goto error;
520 			}
521 			len = 18;
522 			if (hcd->has_tt)
523 				patch_protocol = 1;
524 			break;
525 		case USB_DT_CONFIG << 8:
526 			switch (hcd->driver->flags & HCD_MASK) {
527 			case HCD_USB3:
528 				bufp = ss_rh_config_descriptor;
529 				len = sizeof ss_rh_config_descriptor;
530 				break;
531 			case HCD_USB2:
532 				bufp = hs_rh_config_descriptor;
533 				len = sizeof hs_rh_config_descriptor;
534 				break;
535 			case HCD_USB11:
536 				bufp = fs_rh_config_descriptor;
537 				len = sizeof fs_rh_config_descriptor;
538 				break;
539 			default:
540 				goto error;
541 			}
542 			if (device_can_wakeup(&hcd->self.root_hub->dev))
543 				patch_wakeup = 1;
544 			break;
545 		case USB_DT_STRING << 8:
546 			if ((wValue & 0xff) < 4)
547 				urb->actual_length = rh_string(wValue & 0xff,
548 						hcd, ubuf, wLength);
549 			else /* unsupported IDs --> "protocol stall" */
550 				goto error;
551 			break;
552 		default:
553 			goto error;
554 		}
555 		break;
556 	case DeviceRequest | USB_REQ_GET_INTERFACE:
557 		tbuf [0] = 0;
558 		len = 1;
559 			/* FALLTHROUGH */
560 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
561 		break;
562 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
563 		// wValue == urb->dev->devaddr
564 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
565 			wValue);
566 		break;
567 
568 	/* INTERFACE REQUESTS (no defined feature/status flags) */
569 
570 	/* ENDPOINT REQUESTS */
571 
572 	case EndpointRequest | USB_REQ_GET_STATUS:
573 		// ENDPOINT_HALT flag
574 		tbuf [0] = 0;
575 		tbuf [1] = 0;
576 		len = 2;
577 			/* FALLTHROUGH */
578 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
579 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
580 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
581 		break;
582 
583 	/* CLASS REQUESTS (and errors) */
584 
585 	default:
586 		/* non-generic request */
587 		switch (typeReq) {
588 		case GetHubStatus:
589 		case GetPortStatus:
590 			len = 4;
591 			break;
592 		case GetHubDescriptor:
593 			len = sizeof (struct usb_hub_descriptor);
594 			break;
595 		}
596 		status = hcd->driver->hub_control (hcd,
597 			typeReq, wValue, wIndex,
598 			tbuf, wLength);
599 		break;
600 error:
601 		/* "protocol stall" on error */
602 		status = -EPIPE;
603 	}
604 
605 	if (status) {
606 		len = 0;
607 		if (status != -EPIPE) {
608 			dev_dbg (hcd->self.controller,
609 				"CTRL: TypeReq=0x%x val=0x%x "
610 				"idx=0x%x len=%d ==> %d\n",
611 				typeReq, wValue, wIndex,
612 				wLength, status);
613 		}
614 	}
615 	if (len) {
616 		if (urb->transfer_buffer_length < len)
617 			len = urb->transfer_buffer_length;
618 		urb->actual_length = len;
619 		// always USB_DIR_IN, toward host
620 		memcpy (ubuf, bufp, len);
621 
622 		/* report whether RH hardware supports remote wakeup */
623 		if (patch_wakeup &&
624 				len > offsetof (struct usb_config_descriptor,
625 						bmAttributes))
626 			((struct usb_config_descriptor *)ubuf)->bmAttributes
627 				|= USB_CONFIG_ATT_WAKEUP;
628 
629 		/* report whether RH hardware has an integrated TT */
630 		if (patch_protocol &&
631 				len > offsetof(struct usb_device_descriptor,
632 						bDeviceProtocol))
633 			((struct usb_device_descriptor *) ubuf)->
634 					bDeviceProtocol = 1;
635 	}
636 
637 	/* any errors get returned through the urb completion */
638 	spin_lock_irq(&hcd_root_hub_lock);
639 	usb_hcd_unlink_urb_from_ep(hcd, urb);
640 
641 	/* This peculiar use of spinlocks echoes what real HC drivers do.
642 	 * Avoiding calls to local_irq_disable/enable makes the code
643 	 * RT-friendly.
644 	 */
645 	spin_unlock(&hcd_root_hub_lock);
646 	usb_hcd_giveback_urb(hcd, urb, status);
647 	spin_lock(&hcd_root_hub_lock);
648 
649 	spin_unlock_irq(&hcd_root_hub_lock);
650 	return 0;
651 }
652 
653 /*-------------------------------------------------------------------------*/
654 
655 /*
656  * Root Hub interrupt transfers are polled using a timer if the
657  * driver requests it; otherwise the driver is responsible for
658  * calling usb_hcd_poll_rh_status() when an event occurs.
659  *
660  * Completions are called in_interrupt(), but they may or may not
661  * be in_irq().
662  */
663 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
664 {
665 	struct urb	*urb;
666 	int		length;
667 	unsigned long	flags;
668 	char		buffer[6];	/* Any root hubs with > 31 ports? */
669 
670 	if (unlikely(!hcd->rh_registered))
671 		return;
672 	if (!hcd->uses_new_polling && !hcd->status_urb)
673 		return;
674 
675 	length = hcd->driver->hub_status_data(hcd, buffer);
676 	if (length > 0) {
677 
678 		/* try to complete the status urb */
679 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
680 		urb = hcd->status_urb;
681 		if (urb) {
682 			hcd->poll_pending = 0;
683 			hcd->status_urb = NULL;
684 			urb->actual_length = length;
685 			memcpy(urb->transfer_buffer, buffer, length);
686 
687 			usb_hcd_unlink_urb_from_ep(hcd, urb);
688 			spin_unlock(&hcd_root_hub_lock);
689 			usb_hcd_giveback_urb(hcd, urb, 0);
690 			spin_lock(&hcd_root_hub_lock);
691 		} else {
692 			length = 0;
693 			hcd->poll_pending = 1;
694 		}
695 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
696 	}
697 
698 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
699 	 * exceed that limit if HZ is 100. The math is more clunky than
700 	 * maybe expected, this is to make sure that all timers for USB devices
701 	 * fire at the same time to give the CPU a break inbetween */
702 	if (hcd->uses_new_polling ? hcd->poll_rh :
703 			(length == 0 && hcd->status_urb != NULL))
704 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
705 }
706 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
707 
708 /* timer callback */
709 static void rh_timer_func (unsigned long _hcd)
710 {
711 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
712 }
713 
714 /*-------------------------------------------------------------------------*/
715 
716 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
717 {
718 	int		retval;
719 	unsigned long	flags;
720 	unsigned	len = 1 + (urb->dev->maxchild / 8);
721 
722 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
723 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
724 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
725 		retval = -EINVAL;
726 		goto done;
727 	}
728 
729 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
730 	if (retval)
731 		goto done;
732 
733 	hcd->status_urb = urb;
734 	urb->hcpriv = hcd;	/* indicate it's queued */
735 	if (!hcd->uses_new_polling)
736 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
737 
738 	/* If a status change has already occurred, report it ASAP */
739 	else if (hcd->poll_pending)
740 		mod_timer(&hcd->rh_timer, jiffies);
741 	retval = 0;
742  done:
743 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
744 	return retval;
745 }
746 
747 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
748 {
749 	if (usb_endpoint_xfer_int(&urb->ep->desc))
750 		return rh_queue_status (hcd, urb);
751 	if (usb_endpoint_xfer_control(&urb->ep->desc))
752 		return rh_call_control (hcd, urb);
753 	return -EINVAL;
754 }
755 
756 /*-------------------------------------------------------------------------*/
757 
758 /* Unlinks of root-hub control URBs are legal, but they don't do anything
759  * since these URBs always execute synchronously.
760  */
761 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
762 {
763 	unsigned long	flags;
764 	int		rc;
765 
766 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
767 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
768 	if (rc)
769 		goto done;
770 
771 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
772 		;	/* Do nothing */
773 
774 	} else {				/* Status URB */
775 		if (!hcd->uses_new_polling)
776 			del_timer (&hcd->rh_timer);
777 		if (urb == hcd->status_urb) {
778 			hcd->status_urb = NULL;
779 			usb_hcd_unlink_urb_from_ep(hcd, urb);
780 
781 			spin_unlock(&hcd_root_hub_lock);
782 			usb_hcd_giveback_urb(hcd, urb, status);
783 			spin_lock(&hcd_root_hub_lock);
784 		}
785 	}
786  done:
787 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
788 	return rc;
789 }
790 
791 
792 
793 /*
794  * Show & store the current value of authorized_default
795  */
796 static ssize_t usb_host_authorized_default_show(struct device *dev,
797 						struct device_attribute *attr,
798 						char *buf)
799 {
800 	struct usb_device *rh_usb_dev = to_usb_device(dev);
801 	struct usb_bus *usb_bus = rh_usb_dev->bus;
802 	struct usb_hcd *usb_hcd;
803 
804 	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
805 		return -ENODEV;
806 	usb_hcd = bus_to_hcd(usb_bus);
807 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
808 }
809 
810 static ssize_t usb_host_authorized_default_store(struct device *dev,
811 						 struct device_attribute *attr,
812 						 const char *buf, size_t size)
813 {
814 	ssize_t result;
815 	unsigned val;
816 	struct usb_device *rh_usb_dev = to_usb_device(dev);
817 	struct usb_bus *usb_bus = rh_usb_dev->bus;
818 	struct usb_hcd *usb_hcd;
819 
820 	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
821 		return -ENODEV;
822 	usb_hcd = bus_to_hcd(usb_bus);
823 	result = sscanf(buf, "%u\n", &val);
824 	if (result == 1) {
825 		usb_hcd->authorized_default = val? 1 : 0;
826 		result = size;
827 	}
828 	else
829 		result = -EINVAL;
830 	return result;
831 }
832 
833 static DEVICE_ATTR(authorized_default, 0644,
834 	    usb_host_authorized_default_show,
835 	    usb_host_authorized_default_store);
836 
837 
838 /* Group all the USB bus attributes */
839 static struct attribute *usb_bus_attrs[] = {
840 		&dev_attr_authorized_default.attr,
841 		NULL,
842 };
843 
844 static struct attribute_group usb_bus_attr_group = {
845 	.name = NULL,	/* we want them in the same directory */
846 	.attrs = usb_bus_attrs,
847 };
848 
849 
850 
851 /*-------------------------------------------------------------------------*/
852 
853 /**
854  * usb_bus_init - shared initialization code
855  * @bus: the bus structure being initialized
856  *
857  * This code is used to initialize a usb_bus structure, memory for which is
858  * separately managed.
859  */
860 static void usb_bus_init (struct usb_bus *bus)
861 {
862 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
863 
864 	bus->devnum_next = 1;
865 
866 	bus->root_hub = NULL;
867 	bus->busnum = -1;
868 	bus->bandwidth_allocated = 0;
869 	bus->bandwidth_int_reqs  = 0;
870 	bus->bandwidth_isoc_reqs = 0;
871 
872 	INIT_LIST_HEAD (&bus->bus_list);
873 }
874 
875 /*-------------------------------------------------------------------------*/
876 
877 /**
878  * usb_register_bus - registers the USB host controller with the usb core
879  * @bus: pointer to the bus to register
880  * Context: !in_interrupt()
881  *
882  * Assigns a bus number, and links the controller into usbcore data
883  * structures so that it can be seen by scanning the bus list.
884  */
885 static int usb_register_bus(struct usb_bus *bus)
886 {
887 	int result = -E2BIG;
888 	int busnum;
889 
890 	mutex_lock(&usb_bus_list_lock);
891 	busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
892 	if (busnum >= USB_MAXBUS) {
893 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
894 		goto error_find_busnum;
895 	}
896 	set_bit (busnum, busmap.busmap);
897 	bus->busnum = busnum;
898 
899 	/* Add it to the local list of buses */
900 	list_add (&bus->bus_list, &usb_bus_list);
901 	mutex_unlock(&usb_bus_list_lock);
902 
903 	usb_notify_add_bus(bus);
904 
905 	dev_info (bus->controller, "new USB bus registered, assigned bus "
906 		  "number %d\n", bus->busnum);
907 	return 0;
908 
909 error_find_busnum:
910 	mutex_unlock(&usb_bus_list_lock);
911 	return result;
912 }
913 
914 /**
915  * usb_deregister_bus - deregisters the USB host controller
916  * @bus: pointer to the bus to deregister
917  * Context: !in_interrupt()
918  *
919  * Recycles the bus number, and unlinks the controller from usbcore data
920  * structures so that it won't be seen by scanning the bus list.
921  */
922 static void usb_deregister_bus (struct usb_bus *bus)
923 {
924 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
925 
926 	/*
927 	 * NOTE: make sure that all the devices are removed by the
928 	 * controller code, as well as having it call this when cleaning
929 	 * itself up
930 	 */
931 	mutex_lock(&usb_bus_list_lock);
932 	list_del (&bus->bus_list);
933 	mutex_unlock(&usb_bus_list_lock);
934 
935 	usb_notify_remove_bus(bus);
936 
937 	clear_bit (bus->busnum, busmap.busmap);
938 }
939 
940 /**
941  * register_root_hub - called by usb_add_hcd() to register a root hub
942  * @hcd: host controller for this root hub
943  *
944  * This function registers the root hub with the USB subsystem.  It sets up
945  * the device properly in the device tree and then calls usb_new_device()
946  * to register the usb device.  It also assigns the root hub's USB address
947  * (always 1).
948  */
949 static int register_root_hub(struct usb_hcd *hcd)
950 {
951 	struct device *parent_dev = hcd->self.controller;
952 	struct usb_device *usb_dev = hcd->self.root_hub;
953 	const int devnum = 1;
954 	int retval;
955 
956 	usb_dev->devnum = devnum;
957 	usb_dev->bus->devnum_next = devnum + 1;
958 	memset (&usb_dev->bus->devmap.devicemap, 0,
959 			sizeof usb_dev->bus->devmap.devicemap);
960 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
961 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
962 
963 	mutex_lock(&usb_bus_list_lock);
964 
965 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
966 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
967 	if (retval != sizeof usb_dev->descriptor) {
968 		mutex_unlock(&usb_bus_list_lock);
969 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
970 				dev_name(&usb_dev->dev), retval);
971 		return (retval < 0) ? retval : -EMSGSIZE;
972 	}
973 
974 	retval = usb_new_device (usb_dev);
975 	if (retval) {
976 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
977 				dev_name(&usb_dev->dev), retval);
978 	}
979 	mutex_unlock(&usb_bus_list_lock);
980 
981 	if (retval == 0) {
982 		spin_lock_irq (&hcd_root_hub_lock);
983 		hcd->rh_registered = 1;
984 		spin_unlock_irq (&hcd_root_hub_lock);
985 
986 		/* Did the HC die before the root hub was registered? */
987 		if (hcd->state == HC_STATE_HALT)
988 			usb_hc_died (hcd);	/* This time clean up */
989 	}
990 
991 	return retval;
992 }
993 
994 
995 /*-------------------------------------------------------------------------*/
996 
997 /**
998  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
999  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1000  * @is_input: true iff the transaction sends data to the host
1001  * @isoc: true for isochronous transactions, false for interrupt ones
1002  * @bytecount: how many bytes in the transaction.
1003  *
1004  * Returns approximate bus time in nanoseconds for a periodic transaction.
1005  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1006  * scheduled in software, this function is only used for such scheduling.
1007  */
1008 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1009 {
1010 	unsigned long	tmp;
1011 
1012 	switch (speed) {
1013 	case USB_SPEED_LOW: 	/* INTR only */
1014 		if (is_input) {
1015 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1016 			return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1017 		} else {
1018 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1019 			return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1020 		}
1021 	case USB_SPEED_FULL:	/* ISOC or INTR */
1022 		if (isoc) {
1023 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1024 			return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
1025 		} else {
1026 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1027 			return (9107L + BW_HOST_DELAY + tmp);
1028 		}
1029 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1030 		// FIXME adjust for input vs output
1031 		if (isoc)
1032 			tmp = HS_NSECS_ISO (bytecount);
1033 		else
1034 			tmp = HS_NSECS (bytecount);
1035 		return tmp;
1036 	default:
1037 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1038 		return -1;
1039 	}
1040 }
1041 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1042 
1043 
1044 /*-------------------------------------------------------------------------*/
1045 
1046 /*
1047  * Generic HC operations.
1048  */
1049 
1050 /*-------------------------------------------------------------------------*/
1051 
1052 /**
1053  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1054  * @hcd: host controller to which @urb was submitted
1055  * @urb: URB being submitted
1056  *
1057  * Host controller drivers should call this routine in their enqueue()
1058  * method.  The HCD's private spinlock must be held and interrupts must
1059  * be disabled.  The actions carried out here are required for URB
1060  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1061  *
1062  * Returns 0 for no error, otherwise a negative error code (in which case
1063  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1064  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1065  * the private spinlock and returning.
1066  */
1067 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1068 {
1069 	int		rc = 0;
1070 
1071 	spin_lock(&hcd_urb_list_lock);
1072 
1073 	/* Check that the URB isn't being killed */
1074 	if (unlikely(atomic_read(&urb->reject))) {
1075 		rc = -EPERM;
1076 		goto done;
1077 	}
1078 
1079 	if (unlikely(!urb->ep->enabled)) {
1080 		rc = -ENOENT;
1081 		goto done;
1082 	}
1083 
1084 	if (unlikely(!urb->dev->can_submit)) {
1085 		rc = -EHOSTUNREACH;
1086 		goto done;
1087 	}
1088 
1089 	/*
1090 	 * Check the host controller's state and add the URB to the
1091 	 * endpoint's queue.
1092 	 */
1093 	switch (hcd->state) {
1094 	case HC_STATE_RUNNING:
1095 	case HC_STATE_RESUMING:
1096 		urb->unlinked = 0;
1097 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1098 		break;
1099 	default:
1100 		rc = -ESHUTDOWN;
1101 		goto done;
1102 	}
1103  done:
1104 	spin_unlock(&hcd_urb_list_lock);
1105 	return rc;
1106 }
1107 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1108 
1109 /**
1110  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1111  * @hcd: host controller to which @urb was submitted
1112  * @urb: URB being checked for unlinkability
1113  * @status: error code to store in @urb if the unlink succeeds
1114  *
1115  * Host controller drivers should call this routine in their dequeue()
1116  * method.  The HCD's private spinlock must be held and interrupts must
1117  * be disabled.  The actions carried out here are required for making
1118  * sure than an unlink is valid.
1119  *
1120  * Returns 0 for no error, otherwise a negative error code (in which case
1121  * the dequeue() method must fail).  The possible error codes are:
1122  *
1123  *	-EIDRM: @urb was not submitted or has already completed.
1124  *		The completion function may not have been called yet.
1125  *
1126  *	-EBUSY: @urb has already been unlinked.
1127  */
1128 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1129 		int status)
1130 {
1131 	struct list_head	*tmp;
1132 
1133 	/* insist the urb is still queued */
1134 	list_for_each(tmp, &urb->ep->urb_list) {
1135 		if (tmp == &urb->urb_list)
1136 			break;
1137 	}
1138 	if (tmp != &urb->urb_list)
1139 		return -EIDRM;
1140 
1141 	/* Any status except -EINPROGRESS means something already started to
1142 	 * unlink this URB from the hardware.  So there's no more work to do.
1143 	 */
1144 	if (urb->unlinked)
1145 		return -EBUSY;
1146 	urb->unlinked = status;
1147 
1148 	/* IRQ setup can easily be broken so that USB controllers
1149 	 * never get completion IRQs ... maybe even the ones we need to
1150 	 * finish unlinking the initial failed usb_set_address()
1151 	 * or device descriptor fetch.
1152 	 */
1153 	if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags) &&
1154 			!is_root_hub(urb->dev)) {
1155 		dev_warn(hcd->self.controller, "Unlink after no-IRQ?  "
1156 			"Controller is probably using the wrong IRQ.\n");
1157 		set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1158 	}
1159 
1160 	return 0;
1161 }
1162 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1163 
1164 /**
1165  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1166  * @hcd: host controller to which @urb was submitted
1167  * @urb: URB being unlinked
1168  *
1169  * Host controller drivers should call this routine before calling
1170  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1171  * interrupts must be disabled.  The actions carried out here are required
1172  * for URB completion.
1173  */
1174 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1175 {
1176 	/* clear all state linking urb to this dev (and hcd) */
1177 	spin_lock(&hcd_urb_list_lock);
1178 	list_del_init(&urb->urb_list);
1179 	spin_unlock(&hcd_urb_list_lock);
1180 }
1181 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1182 
1183 /*
1184  * Some usb host controllers can only perform dma using a small SRAM area.
1185  * The usb core itself is however optimized for host controllers that can dma
1186  * using regular system memory - like pci devices doing bus mastering.
1187  *
1188  * To support host controllers with limited dma capabilites we provide dma
1189  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1190  * For this to work properly the host controller code must first use the
1191  * function dma_declare_coherent_memory() to point out which memory area
1192  * that should be used for dma allocations.
1193  *
1194  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1195  * dma using dma_alloc_coherent() which in turn allocates from the memory
1196  * area pointed out with dma_declare_coherent_memory().
1197  *
1198  * So, to summarize...
1199  *
1200  * - We need "local" memory, canonical example being
1201  *   a small SRAM on a discrete controller being the
1202  *   only memory that the controller can read ...
1203  *   (a) "normal" kernel memory is no good, and
1204  *   (b) there's not enough to share
1205  *
1206  * - The only *portable* hook for such stuff in the
1207  *   DMA framework is dma_declare_coherent_memory()
1208  *
1209  * - So we use that, even though the primary requirement
1210  *   is that the memory be "local" (hence addressible
1211  *   by that device), not "coherent".
1212  *
1213  */
1214 
1215 static int hcd_alloc_coherent(struct usb_bus *bus,
1216 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1217 			      void **vaddr_handle, size_t size,
1218 			      enum dma_data_direction dir)
1219 {
1220 	unsigned char *vaddr;
1221 
1222 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1223 				 mem_flags, dma_handle);
1224 	if (!vaddr)
1225 		return -ENOMEM;
1226 
1227 	/*
1228 	 * Store the virtual address of the buffer at the end
1229 	 * of the allocated dma buffer. The size of the buffer
1230 	 * may be uneven so use unaligned functions instead
1231 	 * of just rounding up. It makes sense to optimize for
1232 	 * memory footprint over access speed since the amount
1233 	 * of memory available for dma may be limited.
1234 	 */
1235 	put_unaligned((unsigned long)*vaddr_handle,
1236 		      (unsigned long *)(vaddr + size));
1237 
1238 	if (dir == DMA_TO_DEVICE)
1239 		memcpy(vaddr, *vaddr_handle, size);
1240 
1241 	*vaddr_handle = vaddr;
1242 	return 0;
1243 }
1244 
1245 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1246 			      void **vaddr_handle, size_t size,
1247 			      enum dma_data_direction dir)
1248 {
1249 	unsigned char *vaddr = *vaddr_handle;
1250 
1251 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1252 
1253 	if (dir == DMA_FROM_DEVICE)
1254 		memcpy(vaddr, *vaddr_handle, size);
1255 
1256 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1257 
1258 	*vaddr_handle = vaddr;
1259 	*dma_handle = 0;
1260 }
1261 
1262 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1263 {
1264 	enum dma_data_direction dir;
1265 
1266 	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1267 		dma_unmap_single(hcd->self.controller,
1268 				urb->setup_dma,
1269 				sizeof(struct usb_ctrlrequest),
1270 				DMA_TO_DEVICE);
1271 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1272 		hcd_free_coherent(urb->dev->bus,
1273 				&urb->setup_dma,
1274 				(void **) &urb->setup_packet,
1275 				sizeof(struct usb_ctrlrequest),
1276 				DMA_TO_DEVICE);
1277 
1278 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1279 	if (urb->transfer_flags & URB_DMA_MAP_SG)
1280 		dma_unmap_sg(hcd->self.controller,
1281 				urb->sg,
1282 				urb->num_sgs,
1283 				dir);
1284 	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1285 		dma_unmap_page(hcd->self.controller,
1286 				urb->transfer_dma,
1287 				urb->transfer_buffer_length,
1288 				dir);
1289 	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1290 		dma_unmap_single(hcd->self.controller,
1291 				urb->transfer_dma,
1292 				urb->transfer_buffer_length,
1293 				dir);
1294 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1295 		hcd_free_coherent(urb->dev->bus,
1296 				&urb->transfer_dma,
1297 				&urb->transfer_buffer,
1298 				urb->transfer_buffer_length,
1299 				dir);
1300 
1301 	/* Make it safe to call this routine more than once */
1302 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL |
1303 			URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1304 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1305 }
1306 
1307 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1308 			   gfp_t mem_flags)
1309 {
1310 	enum dma_data_direction dir;
1311 	int ret = 0;
1312 
1313 	/* Map the URB's buffers for DMA access.
1314 	 * Lower level HCD code should use *_dma exclusively,
1315 	 * unless it uses pio or talks to another transport,
1316 	 * or uses the provided scatter gather list for bulk.
1317 	 */
1318 
1319 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1320 		if (hcd->self.uses_dma) {
1321 			urb->setup_dma = dma_map_single(
1322 					hcd->self.controller,
1323 					urb->setup_packet,
1324 					sizeof(struct usb_ctrlrequest),
1325 					DMA_TO_DEVICE);
1326 			if (dma_mapping_error(hcd->self.controller,
1327 						urb->setup_dma))
1328 				return -EAGAIN;
1329 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1330 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1331 			ret = hcd_alloc_coherent(
1332 					urb->dev->bus, mem_flags,
1333 					&urb->setup_dma,
1334 					(void **)&urb->setup_packet,
1335 					sizeof(struct usb_ctrlrequest),
1336 					DMA_TO_DEVICE);
1337 			if (ret)
1338 				return ret;
1339 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1340 		}
1341 	}
1342 
1343 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1344 	if (urb->transfer_buffer_length != 0
1345 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1346 		if (hcd->self.uses_dma) {
1347 			if (urb->num_sgs) {
1348 				int n = dma_map_sg(
1349 						hcd->self.controller,
1350 						urb->sg,
1351 						urb->num_sgs,
1352 						dir);
1353 				if (n <= 0)
1354 					ret = -EAGAIN;
1355 				else
1356 					urb->transfer_flags |= URB_DMA_MAP_SG;
1357 				if (n != urb->num_sgs) {
1358 					urb->num_sgs = n;
1359 					urb->transfer_flags |=
1360 							URB_DMA_SG_COMBINED;
1361 				}
1362 			} else if (urb->sg) {
1363 				struct scatterlist *sg = urb->sg;
1364 				urb->transfer_dma = dma_map_page(
1365 						hcd->self.controller,
1366 						sg_page(sg),
1367 						sg->offset,
1368 						urb->transfer_buffer_length,
1369 						dir);
1370 				if (dma_mapping_error(hcd->self.controller,
1371 						urb->transfer_dma))
1372 					ret = -EAGAIN;
1373 				else
1374 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1375 			} else {
1376 				urb->transfer_dma = dma_map_single(
1377 						hcd->self.controller,
1378 						urb->transfer_buffer,
1379 						urb->transfer_buffer_length,
1380 						dir);
1381 				if (dma_mapping_error(hcd->self.controller,
1382 						urb->transfer_dma))
1383 					ret = -EAGAIN;
1384 				else
1385 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1386 			}
1387 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1388 			ret = hcd_alloc_coherent(
1389 					urb->dev->bus, mem_flags,
1390 					&urb->transfer_dma,
1391 					&urb->transfer_buffer,
1392 					urb->transfer_buffer_length,
1393 					dir);
1394 			if (ret == 0)
1395 				urb->transfer_flags |= URB_MAP_LOCAL;
1396 		}
1397 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1398 				URB_SETUP_MAP_LOCAL)))
1399 			unmap_urb_for_dma(hcd, urb);
1400 	}
1401 	return ret;
1402 }
1403 
1404 /*-------------------------------------------------------------------------*/
1405 
1406 /* may be called in any context with a valid urb->dev usecount
1407  * caller surrenders "ownership" of urb
1408  * expects usb_submit_urb() to have sanity checked and conditioned all
1409  * inputs in the urb
1410  */
1411 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1412 {
1413 	int			status;
1414 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1415 
1416 	/* increment urb's reference count as part of giving it to the HCD
1417 	 * (which will control it).  HCD guarantees that it either returns
1418 	 * an error or calls giveback(), but not both.
1419 	 */
1420 	usb_get_urb(urb);
1421 	atomic_inc(&urb->use_count);
1422 	atomic_inc(&urb->dev->urbnum);
1423 	usbmon_urb_submit(&hcd->self, urb);
1424 
1425 	/* NOTE requirements on root-hub callers (usbfs and the hub
1426 	 * driver, for now):  URBs' urb->transfer_buffer must be
1427 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1428 	 * they could clobber root hub response data.  Also, control
1429 	 * URBs must be submitted in process context with interrupts
1430 	 * enabled.
1431 	 */
1432 
1433 	if (is_root_hub(urb->dev)) {
1434 		status = rh_urb_enqueue(hcd, urb);
1435 	} else {
1436 		status = map_urb_for_dma(hcd, urb, mem_flags);
1437 		if (likely(status == 0)) {
1438 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1439 			if (unlikely(status))
1440 				unmap_urb_for_dma(hcd, urb);
1441 		}
1442 	}
1443 
1444 	if (unlikely(status)) {
1445 		usbmon_urb_submit_error(&hcd->self, urb, status);
1446 		urb->hcpriv = NULL;
1447 		INIT_LIST_HEAD(&urb->urb_list);
1448 		atomic_dec(&urb->use_count);
1449 		atomic_dec(&urb->dev->urbnum);
1450 		if (atomic_read(&urb->reject))
1451 			wake_up(&usb_kill_urb_queue);
1452 		usb_put_urb(urb);
1453 	}
1454 	return status;
1455 }
1456 
1457 /*-------------------------------------------------------------------------*/
1458 
1459 /* this makes the hcd giveback() the urb more quickly, by kicking it
1460  * off hardware queues (which may take a while) and returning it as
1461  * soon as practical.  we've already set up the urb's return status,
1462  * but we can't know if the callback completed already.
1463  */
1464 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1465 {
1466 	int		value;
1467 
1468 	if (is_root_hub(urb->dev))
1469 		value = usb_rh_urb_dequeue(hcd, urb, status);
1470 	else {
1471 
1472 		/* The only reason an HCD might fail this call is if
1473 		 * it has not yet fully queued the urb to begin with.
1474 		 * Such failures should be harmless. */
1475 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1476 	}
1477 	return value;
1478 }
1479 
1480 /*
1481  * called in any context
1482  *
1483  * caller guarantees urb won't be recycled till both unlink()
1484  * and the urb's completion function return
1485  */
1486 int usb_hcd_unlink_urb (struct urb *urb, int status)
1487 {
1488 	struct usb_hcd		*hcd;
1489 	int			retval = -EIDRM;
1490 	unsigned long		flags;
1491 
1492 	/* Prevent the device and bus from going away while
1493 	 * the unlink is carried out.  If they are already gone
1494 	 * then urb->use_count must be 0, since disconnected
1495 	 * devices can't have any active URBs.
1496 	 */
1497 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1498 	if (atomic_read(&urb->use_count) > 0) {
1499 		retval = 0;
1500 		usb_get_dev(urb->dev);
1501 	}
1502 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1503 	if (retval == 0) {
1504 		hcd = bus_to_hcd(urb->dev->bus);
1505 		retval = unlink1(hcd, urb, status);
1506 		usb_put_dev(urb->dev);
1507 	}
1508 
1509 	if (retval == 0)
1510 		retval = -EINPROGRESS;
1511 	else if (retval != -EIDRM && retval != -EBUSY)
1512 		dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
1513 				urb, retval);
1514 	return retval;
1515 }
1516 
1517 /*-------------------------------------------------------------------------*/
1518 
1519 /**
1520  * usb_hcd_giveback_urb - return URB from HCD to device driver
1521  * @hcd: host controller returning the URB
1522  * @urb: urb being returned to the USB device driver.
1523  * @status: completion status code for the URB.
1524  * Context: in_interrupt()
1525  *
1526  * This hands the URB from HCD to its USB device driver, using its
1527  * completion function.  The HCD has freed all per-urb resources
1528  * (and is done using urb->hcpriv).  It also released all HCD locks;
1529  * the device driver won't cause problems if it frees, modifies,
1530  * or resubmits this URB.
1531  *
1532  * If @urb was unlinked, the value of @status will be overridden by
1533  * @urb->unlinked.  Erroneous short transfers are detected in case
1534  * the HCD hasn't checked for them.
1535  */
1536 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1537 {
1538 	urb->hcpriv = NULL;
1539 	if (unlikely(urb->unlinked))
1540 		status = urb->unlinked;
1541 	else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1542 			urb->actual_length < urb->transfer_buffer_length &&
1543 			!status))
1544 		status = -EREMOTEIO;
1545 
1546 	unmap_urb_for_dma(hcd, urb);
1547 	usbmon_urb_complete(&hcd->self, urb, status);
1548 	usb_unanchor_urb(urb);
1549 
1550 	/* pass ownership to the completion handler */
1551 	urb->status = status;
1552 	urb->complete (urb);
1553 	atomic_dec (&urb->use_count);
1554 	if (unlikely(atomic_read(&urb->reject)))
1555 		wake_up (&usb_kill_urb_queue);
1556 	usb_put_urb (urb);
1557 }
1558 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1559 
1560 /*-------------------------------------------------------------------------*/
1561 
1562 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1563  * queue to drain completely.  The caller must first insure that no more
1564  * URBs can be submitted for this endpoint.
1565  */
1566 void usb_hcd_flush_endpoint(struct usb_device *udev,
1567 		struct usb_host_endpoint *ep)
1568 {
1569 	struct usb_hcd		*hcd;
1570 	struct urb		*urb;
1571 
1572 	if (!ep)
1573 		return;
1574 	might_sleep();
1575 	hcd = bus_to_hcd(udev->bus);
1576 
1577 	/* No more submits can occur */
1578 	spin_lock_irq(&hcd_urb_list_lock);
1579 rescan:
1580 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1581 		int	is_in;
1582 
1583 		if (urb->unlinked)
1584 			continue;
1585 		usb_get_urb (urb);
1586 		is_in = usb_urb_dir_in(urb);
1587 		spin_unlock(&hcd_urb_list_lock);
1588 
1589 		/* kick hcd */
1590 		unlink1(hcd, urb, -ESHUTDOWN);
1591 		dev_dbg (hcd->self.controller,
1592 			"shutdown urb %p ep%d%s%s\n",
1593 			urb, usb_endpoint_num(&ep->desc),
1594 			is_in ? "in" : "out",
1595 			({	char *s;
1596 
1597 				 switch (usb_endpoint_type(&ep->desc)) {
1598 				 case USB_ENDPOINT_XFER_CONTROL:
1599 					s = ""; break;
1600 				 case USB_ENDPOINT_XFER_BULK:
1601 					s = "-bulk"; break;
1602 				 case USB_ENDPOINT_XFER_INT:
1603 					s = "-intr"; break;
1604 				 default:
1605 			 		s = "-iso"; break;
1606 				};
1607 				s;
1608 			}));
1609 		usb_put_urb (urb);
1610 
1611 		/* list contents may have changed */
1612 		spin_lock(&hcd_urb_list_lock);
1613 		goto rescan;
1614 	}
1615 	spin_unlock_irq(&hcd_urb_list_lock);
1616 
1617 	/* Wait until the endpoint queue is completely empty */
1618 	while (!list_empty (&ep->urb_list)) {
1619 		spin_lock_irq(&hcd_urb_list_lock);
1620 
1621 		/* The list may have changed while we acquired the spinlock */
1622 		urb = NULL;
1623 		if (!list_empty (&ep->urb_list)) {
1624 			urb = list_entry (ep->urb_list.prev, struct urb,
1625 					urb_list);
1626 			usb_get_urb (urb);
1627 		}
1628 		spin_unlock_irq(&hcd_urb_list_lock);
1629 
1630 		if (urb) {
1631 			usb_kill_urb (urb);
1632 			usb_put_urb (urb);
1633 		}
1634 	}
1635 }
1636 
1637 /**
1638  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1639  *				the bus bandwidth
1640  * @udev: target &usb_device
1641  * @new_config: new configuration to install
1642  * @cur_alt: the current alternate interface setting
1643  * @new_alt: alternate interface setting that is being installed
1644  *
1645  * To change configurations, pass in the new configuration in new_config,
1646  * and pass NULL for cur_alt and new_alt.
1647  *
1648  * To reset a device's configuration (put the device in the ADDRESSED state),
1649  * pass in NULL for new_config, cur_alt, and new_alt.
1650  *
1651  * To change alternate interface settings, pass in NULL for new_config,
1652  * pass in the current alternate interface setting in cur_alt,
1653  * and pass in the new alternate interface setting in new_alt.
1654  *
1655  * Returns an error if the requested bandwidth change exceeds the
1656  * bus bandwidth or host controller internal resources.
1657  */
1658 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1659 		struct usb_host_config *new_config,
1660 		struct usb_host_interface *cur_alt,
1661 		struct usb_host_interface *new_alt)
1662 {
1663 	int num_intfs, i, j;
1664 	struct usb_host_interface *alt = NULL;
1665 	int ret = 0;
1666 	struct usb_hcd *hcd;
1667 	struct usb_host_endpoint *ep;
1668 
1669 	hcd = bus_to_hcd(udev->bus);
1670 	if (!hcd->driver->check_bandwidth)
1671 		return 0;
1672 
1673 	/* Configuration is being removed - set configuration 0 */
1674 	if (!new_config && !cur_alt) {
1675 		for (i = 1; i < 16; ++i) {
1676 			ep = udev->ep_out[i];
1677 			if (ep)
1678 				hcd->driver->drop_endpoint(hcd, udev, ep);
1679 			ep = udev->ep_in[i];
1680 			if (ep)
1681 				hcd->driver->drop_endpoint(hcd, udev, ep);
1682 		}
1683 		hcd->driver->check_bandwidth(hcd, udev);
1684 		return 0;
1685 	}
1686 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1687 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1688 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1689 	 * ok to exclude it.
1690 	 */
1691 	if (new_config) {
1692 		num_intfs = new_config->desc.bNumInterfaces;
1693 		/* Remove endpoints (except endpoint 0, which is always on the
1694 		 * schedule) from the old config from the schedule
1695 		 */
1696 		for (i = 1; i < 16; ++i) {
1697 			ep = udev->ep_out[i];
1698 			if (ep) {
1699 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1700 				if (ret < 0)
1701 					goto reset;
1702 			}
1703 			ep = udev->ep_in[i];
1704 			if (ep) {
1705 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1706 				if (ret < 0)
1707 					goto reset;
1708 			}
1709 		}
1710 		for (i = 0; i < num_intfs; ++i) {
1711 			struct usb_host_interface *first_alt;
1712 			int iface_num;
1713 
1714 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1715 			iface_num = first_alt->desc.bInterfaceNumber;
1716 			/* Set up endpoints for alternate interface setting 0 */
1717 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1718 			if (!alt)
1719 				/* No alt setting 0? Pick the first setting. */
1720 				alt = first_alt;
1721 
1722 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1723 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1724 				if (ret < 0)
1725 					goto reset;
1726 			}
1727 		}
1728 	}
1729 	if (cur_alt && new_alt) {
1730 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1731 				cur_alt->desc.bInterfaceNumber);
1732 
1733 		if (iface->resetting_device) {
1734 			/*
1735 			 * The USB core just reset the device, so the xHCI host
1736 			 * and the device will think alt setting 0 is installed.
1737 			 * However, the USB core will pass in the alternate
1738 			 * setting installed before the reset as cur_alt.  Dig
1739 			 * out the alternate setting 0 structure, or the first
1740 			 * alternate setting if a broken device doesn't have alt
1741 			 * setting 0.
1742 			 */
1743 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1744 			if (!cur_alt)
1745 				cur_alt = &iface->altsetting[0];
1746 		}
1747 
1748 		/* Drop all the endpoints in the current alt setting */
1749 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1750 			ret = hcd->driver->drop_endpoint(hcd, udev,
1751 					&cur_alt->endpoint[i]);
1752 			if (ret < 0)
1753 				goto reset;
1754 		}
1755 		/* Add all the endpoints in the new alt setting */
1756 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1757 			ret = hcd->driver->add_endpoint(hcd, udev,
1758 					&new_alt->endpoint[i]);
1759 			if (ret < 0)
1760 				goto reset;
1761 		}
1762 	}
1763 	ret = hcd->driver->check_bandwidth(hcd, udev);
1764 reset:
1765 	if (ret < 0)
1766 		hcd->driver->reset_bandwidth(hcd, udev);
1767 	return ret;
1768 }
1769 
1770 /* Disables the endpoint: synchronizes with the hcd to make sure all
1771  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1772  * have been called previously.  Use for set_configuration, set_interface,
1773  * driver removal, physical disconnect.
1774  *
1775  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1776  * type, maxpacket size, toggle, halt status, and scheduling.
1777  */
1778 void usb_hcd_disable_endpoint(struct usb_device *udev,
1779 		struct usb_host_endpoint *ep)
1780 {
1781 	struct usb_hcd		*hcd;
1782 
1783 	might_sleep();
1784 	hcd = bus_to_hcd(udev->bus);
1785 	if (hcd->driver->endpoint_disable)
1786 		hcd->driver->endpoint_disable(hcd, ep);
1787 }
1788 
1789 /**
1790  * usb_hcd_reset_endpoint - reset host endpoint state
1791  * @udev: USB device.
1792  * @ep:   the endpoint to reset.
1793  *
1794  * Resets any host endpoint state such as the toggle bit, sequence
1795  * number and current window.
1796  */
1797 void usb_hcd_reset_endpoint(struct usb_device *udev,
1798 			    struct usb_host_endpoint *ep)
1799 {
1800 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1801 
1802 	if (hcd->driver->endpoint_reset)
1803 		hcd->driver->endpoint_reset(hcd, ep);
1804 	else {
1805 		int epnum = usb_endpoint_num(&ep->desc);
1806 		int is_out = usb_endpoint_dir_out(&ep->desc);
1807 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1808 
1809 		usb_settoggle(udev, epnum, is_out, 0);
1810 		if (is_control)
1811 			usb_settoggle(udev, epnum, !is_out, 0);
1812 	}
1813 }
1814 
1815 /**
1816  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1817  * @interface:		alternate setting that includes all endpoints.
1818  * @eps:		array of endpoints that need streams.
1819  * @num_eps:		number of endpoints in the array.
1820  * @num_streams:	number of streams to allocate.
1821  * @mem_flags:		flags hcd should use to allocate memory.
1822  *
1823  * Sets up a group of bulk endpoints to have num_streams stream IDs available.
1824  * Drivers may queue multiple transfers to different stream IDs, which may
1825  * complete in a different order than they were queued.
1826  */
1827 int usb_alloc_streams(struct usb_interface *interface,
1828 		struct usb_host_endpoint **eps, unsigned int num_eps,
1829 		unsigned int num_streams, gfp_t mem_flags)
1830 {
1831 	struct usb_hcd *hcd;
1832 	struct usb_device *dev;
1833 	int i;
1834 
1835 	dev = interface_to_usbdev(interface);
1836 	hcd = bus_to_hcd(dev->bus);
1837 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
1838 		return -EINVAL;
1839 	if (dev->speed != USB_SPEED_SUPER)
1840 		return -EINVAL;
1841 
1842 	/* Streams only apply to bulk endpoints. */
1843 	for (i = 0; i < num_eps; i++)
1844 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
1845 			return -EINVAL;
1846 
1847 	return hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
1848 			num_streams, mem_flags);
1849 }
1850 EXPORT_SYMBOL_GPL(usb_alloc_streams);
1851 
1852 /**
1853  * usb_free_streams - free bulk endpoint stream IDs.
1854  * @interface:	alternate setting that includes all endpoints.
1855  * @eps:	array of endpoints to remove streams from.
1856  * @num_eps:	number of endpoints in the array.
1857  * @mem_flags:	flags hcd should use to allocate memory.
1858  *
1859  * Reverts a group of bulk endpoints back to not using stream IDs.
1860  * Can fail if we are given bad arguments, or HCD is broken.
1861  */
1862 void usb_free_streams(struct usb_interface *interface,
1863 		struct usb_host_endpoint **eps, unsigned int num_eps,
1864 		gfp_t mem_flags)
1865 {
1866 	struct usb_hcd *hcd;
1867 	struct usb_device *dev;
1868 	int i;
1869 
1870 	dev = interface_to_usbdev(interface);
1871 	hcd = bus_to_hcd(dev->bus);
1872 	if (dev->speed != USB_SPEED_SUPER)
1873 		return;
1874 
1875 	/* Streams only apply to bulk endpoints. */
1876 	for (i = 0; i < num_eps; i++)
1877 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
1878 			return;
1879 
1880 	hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
1881 }
1882 EXPORT_SYMBOL_GPL(usb_free_streams);
1883 
1884 /* Protect against drivers that try to unlink URBs after the device
1885  * is gone, by waiting until all unlinks for @udev are finished.
1886  * Since we don't currently track URBs by device, simply wait until
1887  * nothing is running in the locked region of usb_hcd_unlink_urb().
1888  */
1889 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
1890 {
1891 	spin_lock_irq(&hcd_urb_unlink_lock);
1892 	spin_unlock_irq(&hcd_urb_unlink_lock);
1893 }
1894 
1895 /*-------------------------------------------------------------------------*/
1896 
1897 /* called in any context */
1898 int usb_hcd_get_frame_number (struct usb_device *udev)
1899 {
1900 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
1901 
1902 	if (!HC_IS_RUNNING (hcd->state))
1903 		return -ESHUTDOWN;
1904 	return hcd->driver->get_frame_number (hcd);
1905 }
1906 
1907 /*-------------------------------------------------------------------------*/
1908 
1909 #ifdef	CONFIG_PM
1910 
1911 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
1912 {
1913 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
1914 	int		status;
1915 	int		old_state = hcd->state;
1916 
1917 	dev_dbg(&rhdev->dev, "bus %s%s\n",
1918 			(msg.event & PM_EVENT_AUTO ? "auto-" : ""), "suspend");
1919 	if (!hcd->driver->bus_suspend) {
1920 		status = -ENOENT;
1921 	} else {
1922 		hcd->state = HC_STATE_QUIESCING;
1923 		status = hcd->driver->bus_suspend(hcd);
1924 	}
1925 	if (status == 0) {
1926 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
1927 		hcd->state = HC_STATE_SUSPENDED;
1928 	} else {
1929 		hcd->state = old_state;
1930 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1931 				"suspend", status);
1932 	}
1933 	return status;
1934 }
1935 
1936 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
1937 {
1938 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
1939 	int		status;
1940 	int		old_state = hcd->state;
1941 
1942 	dev_dbg(&rhdev->dev, "usb %s%s\n",
1943 			(msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume");
1944 	if (!hcd->driver->bus_resume)
1945 		return -ENOENT;
1946 	if (hcd->state == HC_STATE_RUNNING)
1947 		return 0;
1948 
1949 	hcd->state = HC_STATE_RESUMING;
1950 	status = hcd->driver->bus_resume(hcd);
1951 	if (status == 0) {
1952 		/* TRSMRCY = 10 msec */
1953 		msleep(10);
1954 		usb_set_device_state(rhdev, rhdev->actconfig
1955 				? USB_STATE_CONFIGURED
1956 				: USB_STATE_ADDRESS);
1957 		hcd->state = HC_STATE_RUNNING;
1958 	} else {
1959 		hcd->state = old_state;
1960 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1961 				"resume", status);
1962 		if (status != -ESHUTDOWN)
1963 			usb_hc_died(hcd);
1964 	}
1965 	return status;
1966 }
1967 
1968 #endif	/* CONFIG_PM */
1969 
1970 #ifdef	CONFIG_USB_SUSPEND
1971 
1972 /* Workqueue routine for root-hub remote wakeup */
1973 static void hcd_resume_work(struct work_struct *work)
1974 {
1975 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
1976 	struct usb_device *udev = hcd->self.root_hub;
1977 
1978 	usb_lock_device(udev);
1979 	usb_remote_wakeup(udev);
1980 	usb_unlock_device(udev);
1981 }
1982 
1983 /**
1984  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
1985  * @hcd: host controller for this root hub
1986  *
1987  * The USB host controller calls this function when its root hub is
1988  * suspended (with the remote wakeup feature enabled) and a remote
1989  * wakeup request is received.  The routine submits a workqueue request
1990  * to resume the root hub (that is, manage its downstream ports again).
1991  */
1992 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
1993 {
1994 	unsigned long flags;
1995 
1996 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
1997 	if (hcd->rh_registered)
1998 		queue_work(pm_wq, &hcd->wakeup_work);
1999 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2000 }
2001 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2002 
2003 #endif	/* CONFIG_USB_SUSPEND */
2004 
2005 /*-------------------------------------------------------------------------*/
2006 
2007 #ifdef	CONFIG_USB_OTG
2008 
2009 /**
2010  * usb_bus_start_enum - start immediate enumeration (for OTG)
2011  * @bus: the bus (must use hcd framework)
2012  * @port_num: 1-based number of port; usually bus->otg_port
2013  * Context: in_interrupt()
2014  *
2015  * Starts enumeration, with an immediate reset followed later by
2016  * khubd identifying and possibly configuring the device.
2017  * This is needed by OTG controller drivers, where it helps meet
2018  * HNP protocol timing requirements for starting a port reset.
2019  */
2020 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2021 {
2022 	struct usb_hcd		*hcd;
2023 	int			status = -EOPNOTSUPP;
2024 
2025 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2026 	 * boards with root hubs hooked up to internal devices (instead of
2027 	 * just the OTG port) may need more attention to resetting...
2028 	 */
2029 	hcd = container_of (bus, struct usb_hcd, self);
2030 	if (port_num && hcd->driver->start_port_reset)
2031 		status = hcd->driver->start_port_reset(hcd, port_num);
2032 
2033 	/* run khubd shortly after (first) root port reset finishes;
2034 	 * it may issue others, until at least 50 msecs have passed.
2035 	 */
2036 	if (status == 0)
2037 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2038 	return status;
2039 }
2040 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2041 
2042 #endif
2043 
2044 /*-------------------------------------------------------------------------*/
2045 
2046 /**
2047  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2048  * @irq: the IRQ being raised
2049  * @__hcd: pointer to the HCD whose IRQ is being signaled
2050  *
2051  * If the controller isn't HALTed, calls the driver's irq handler.
2052  * Checks whether the controller is now dead.
2053  */
2054 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2055 {
2056 	struct usb_hcd		*hcd = __hcd;
2057 	unsigned long		flags;
2058 	irqreturn_t		rc;
2059 
2060 	/* IRQF_DISABLED doesn't work correctly with shared IRQs
2061 	 * when the first handler doesn't use it.  So let's just
2062 	 * assume it's never used.
2063 	 */
2064 	local_irq_save(flags);
2065 
2066 	if (unlikely(hcd->state == HC_STATE_HALT ||
2067 		     !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
2068 		rc = IRQ_NONE;
2069 	} else if (hcd->driver->irq(hcd) == IRQ_NONE) {
2070 		rc = IRQ_NONE;
2071 	} else {
2072 		set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
2073 
2074 		if (unlikely(hcd->state == HC_STATE_HALT))
2075 			usb_hc_died(hcd);
2076 		rc = IRQ_HANDLED;
2077 	}
2078 
2079 	local_irq_restore(flags);
2080 	return rc;
2081 }
2082 
2083 /*-------------------------------------------------------------------------*/
2084 
2085 /**
2086  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2087  * @hcd: pointer to the HCD representing the controller
2088  *
2089  * This is called by bus glue to report a USB host controller that died
2090  * while operations may still have been pending.  It's called automatically
2091  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2092  */
2093 void usb_hc_died (struct usb_hcd *hcd)
2094 {
2095 	unsigned long flags;
2096 
2097 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2098 
2099 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2100 	if (hcd->rh_registered) {
2101 		hcd->poll_rh = 0;
2102 
2103 		/* make khubd clean up old urbs and devices */
2104 		usb_set_device_state (hcd->self.root_hub,
2105 				USB_STATE_NOTATTACHED);
2106 		usb_kick_khubd (hcd->self.root_hub);
2107 	}
2108 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2109 }
2110 EXPORT_SYMBOL_GPL (usb_hc_died);
2111 
2112 /*-------------------------------------------------------------------------*/
2113 
2114 /**
2115  * usb_create_hcd - create and initialize an HCD structure
2116  * @driver: HC driver that will use this hcd
2117  * @dev: device for this HC, stored in hcd->self.controller
2118  * @bus_name: value to store in hcd->self.bus_name
2119  * Context: !in_interrupt()
2120  *
2121  * Allocate a struct usb_hcd, with extra space at the end for the
2122  * HC driver's private data.  Initialize the generic members of the
2123  * hcd structure.
2124  *
2125  * If memory is unavailable, returns NULL.
2126  */
2127 struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
2128 		struct device *dev, const char *bus_name)
2129 {
2130 	struct usb_hcd *hcd;
2131 
2132 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2133 	if (!hcd) {
2134 		dev_dbg (dev, "hcd alloc failed\n");
2135 		return NULL;
2136 	}
2137 	dev_set_drvdata(dev, hcd);
2138 	kref_init(&hcd->kref);
2139 
2140 	usb_bus_init(&hcd->self);
2141 	hcd->self.controller = dev;
2142 	hcd->self.bus_name = bus_name;
2143 	hcd->self.uses_dma = (dev->dma_mask != NULL);
2144 
2145 	init_timer(&hcd->rh_timer);
2146 	hcd->rh_timer.function = rh_timer_func;
2147 	hcd->rh_timer.data = (unsigned long) hcd;
2148 #ifdef CONFIG_USB_SUSPEND
2149 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2150 #endif
2151 	mutex_init(&hcd->bandwidth_mutex);
2152 
2153 	hcd->driver = driver;
2154 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2155 			"USB Host Controller";
2156 	return hcd;
2157 }
2158 EXPORT_SYMBOL_GPL(usb_create_hcd);
2159 
2160 static void hcd_release (struct kref *kref)
2161 {
2162 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2163 
2164 	kfree(hcd);
2165 }
2166 
2167 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2168 {
2169 	if (hcd)
2170 		kref_get (&hcd->kref);
2171 	return hcd;
2172 }
2173 EXPORT_SYMBOL_GPL(usb_get_hcd);
2174 
2175 void usb_put_hcd (struct usb_hcd *hcd)
2176 {
2177 	if (hcd)
2178 		kref_put (&hcd->kref, hcd_release);
2179 }
2180 EXPORT_SYMBOL_GPL(usb_put_hcd);
2181 
2182 /**
2183  * usb_add_hcd - finish generic HCD structure initialization and register
2184  * @hcd: the usb_hcd structure to initialize
2185  * @irqnum: Interrupt line to allocate
2186  * @irqflags: Interrupt type flags
2187  *
2188  * Finish the remaining parts of generic HCD initialization: allocate the
2189  * buffers of consistent memory, register the bus, request the IRQ line,
2190  * and call the driver's reset() and start() routines.
2191  */
2192 int usb_add_hcd(struct usb_hcd *hcd,
2193 		unsigned int irqnum, unsigned long irqflags)
2194 {
2195 	int retval;
2196 	struct usb_device *rhdev;
2197 
2198 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2199 
2200 	hcd->authorized_default = hcd->wireless? 0 : 1;
2201 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2202 
2203 	/* HC is in reset state, but accessible.  Now do the one-time init,
2204 	 * bottom up so that hcds can customize the root hubs before khubd
2205 	 * starts talking to them.  (Note, bus id is assigned early too.)
2206 	 */
2207 	if ((retval = hcd_buffer_create(hcd)) != 0) {
2208 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
2209 		return retval;
2210 	}
2211 
2212 	if ((retval = usb_register_bus(&hcd->self)) < 0)
2213 		goto err_register_bus;
2214 
2215 	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
2216 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
2217 		retval = -ENOMEM;
2218 		goto err_allocate_root_hub;
2219 	}
2220 
2221 	switch (hcd->driver->flags & HCD_MASK) {
2222 	case HCD_USB11:
2223 		rhdev->speed = USB_SPEED_FULL;
2224 		break;
2225 	case HCD_USB2:
2226 		rhdev->speed = USB_SPEED_HIGH;
2227 		break;
2228 	case HCD_USB3:
2229 		rhdev->speed = USB_SPEED_SUPER;
2230 		break;
2231 	default:
2232 		goto err_allocate_root_hub;
2233 	}
2234 	hcd->self.root_hub = rhdev;
2235 
2236 	/* wakeup flag init defaults to "everything works" for root hubs,
2237 	 * but drivers can override it in reset() if needed, along with
2238 	 * recording the overall controller's system wakeup capability.
2239 	 */
2240 	device_init_wakeup(&rhdev->dev, 1);
2241 
2242 	/* "reset" is misnamed; its role is now one-time init. the controller
2243 	 * should already have been reset (and boot firmware kicked off etc).
2244 	 */
2245 	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
2246 		dev_err(hcd->self.controller, "can't setup\n");
2247 		goto err_hcd_driver_setup;
2248 	}
2249 
2250 	/* NOTE: root hub and controller capabilities may not be the same */
2251 	if (device_can_wakeup(hcd->self.controller)
2252 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2253 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2254 
2255 	/* enable irqs just before we start the controller */
2256 	if (hcd->driver->irq) {
2257 
2258 		/* IRQF_DISABLED doesn't work as advertised when used together
2259 		 * with IRQF_SHARED. As usb_hcd_irq() will always disable
2260 		 * interrupts we can remove it here.
2261 		 */
2262 		if (irqflags & IRQF_SHARED)
2263 			irqflags &= ~IRQF_DISABLED;
2264 
2265 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2266 				hcd->driver->description, hcd->self.busnum);
2267 		if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2268 				hcd->irq_descr, hcd)) != 0) {
2269 			dev_err(hcd->self.controller,
2270 					"request interrupt %d failed\n", irqnum);
2271 			goto err_request_irq;
2272 		}
2273 		hcd->irq = irqnum;
2274 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2275 				(hcd->driver->flags & HCD_MEMORY) ?
2276 					"io mem" : "io base",
2277 					(unsigned long long)hcd->rsrc_start);
2278 	} else {
2279 		hcd->irq = -1;
2280 		if (hcd->rsrc_start)
2281 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2282 					(hcd->driver->flags & HCD_MEMORY) ?
2283 					"io mem" : "io base",
2284 					(unsigned long long)hcd->rsrc_start);
2285 	}
2286 
2287 	if ((retval = hcd->driver->start(hcd)) < 0) {
2288 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2289 		goto err_hcd_driver_start;
2290 	}
2291 
2292 	/* starting here, usbcore will pay attention to this root hub */
2293 	rhdev->bus_mA = min(500u, hcd->power_budget);
2294 	if ((retval = register_root_hub(hcd)) != 0)
2295 		goto err_register_root_hub;
2296 
2297 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2298 	if (retval < 0) {
2299 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2300 		       retval);
2301 		goto error_create_attr_group;
2302 	}
2303 	if (hcd->uses_new_polling && hcd->poll_rh)
2304 		usb_hcd_poll_rh_status(hcd);
2305 	return retval;
2306 
2307 error_create_attr_group:
2308 	mutex_lock(&usb_bus_list_lock);
2309 	usb_disconnect(&hcd->self.root_hub);
2310 	mutex_unlock(&usb_bus_list_lock);
2311 err_register_root_hub:
2312 	hcd->driver->stop(hcd);
2313 err_hcd_driver_start:
2314 	if (hcd->irq >= 0)
2315 		free_irq(irqnum, hcd);
2316 err_request_irq:
2317 err_hcd_driver_setup:
2318 	hcd->self.root_hub = NULL;
2319 	usb_put_dev(rhdev);
2320 err_allocate_root_hub:
2321 	usb_deregister_bus(&hcd->self);
2322 err_register_bus:
2323 	hcd_buffer_destroy(hcd);
2324 	return retval;
2325 }
2326 EXPORT_SYMBOL_GPL(usb_add_hcd);
2327 
2328 /**
2329  * usb_remove_hcd - shutdown processing for generic HCDs
2330  * @hcd: the usb_hcd structure to remove
2331  * Context: !in_interrupt()
2332  *
2333  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2334  * invoking the HCD's stop() method.
2335  */
2336 void usb_remove_hcd(struct usb_hcd *hcd)
2337 {
2338 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2339 
2340 	if (HC_IS_RUNNING (hcd->state))
2341 		hcd->state = HC_STATE_QUIESCING;
2342 
2343 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2344 	spin_lock_irq (&hcd_root_hub_lock);
2345 	hcd->rh_registered = 0;
2346 	spin_unlock_irq (&hcd_root_hub_lock);
2347 
2348 #ifdef CONFIG_USB_SUSPEND
2349 	cancel_work_sync(&hcd->wakeup_work);
2350 #endif
2351 
2352 	sysfs_remove_group(&hcd->self.root_hub->dev.kobj, &usb_bus_attr_group);
2353 	mutex_lock(&usb_bus_list_lock);
2354 	usb_disconnect(&hcd->self.root_hub);
2355 	mutex_unlock(&usb_bus_list_lock);
2356 
2357 	hcd->driver->stop(hcd);
2358 	hcd->state = HC_STATE_HALT;
2359 
2360 	hcd->poll_rh = 0;
2361 	del_timer_sync(&hcd->rh_timer);
2362 
2363 	if (hcd->irq >= 0)
2364 		free_irq(hcd->irq, hcd);
2365 	usb_deregister_bus(&hcd->self);
2366 	hcd_buffer_destroy(hcd);
2367 }
2368 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2369 
2370 void
2371 usb_hcd_platform_shutdown(struct platform_device* dev)
2372 {
2373 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2374 
2375 	if (hcd->driver->shutdown)
2376 		hcd->driver->shutdown(hcd);
2377 }
2378 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2379 
2380 /*-------------------------------------------------------------------------*/
2381 
2382 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2383 
2384 struct usb_mon_operations *mon_ops;
2385 
2386 /*
2387  * The registration is unlocked.
2388  * We do it this way because we do not want to lock in hot paths.
2389  *
2390  * Notice that the code is minimally error-proof. Because usbmon needs
2391  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2392  */
2393 
2394 int usb_mon_register (struct usb_mon_operations *ops)
2395 {
2396 
2397 	if (mon_ops)
2398 		return -EBUSY;
2399 
2400 	mon_ops = ops;
2401 	mb();
2402 	return 0;
2403 }
2404 EXPORT_SYMBOL_GPL (usb_mon_register);
2405 
2406 void usb_mon_deregister (void)
2407 {
2408 
2409 	if (mon_ops == NULL) {
2410 		printk(KERN_ERR "USB: monitor was not registered\n");
2411 		return;
2412 	}
2413 	mon_ops = NULL;
2414 	mb();
2415 }
2416 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2417 
2418 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2419