xref: /openbmc/linux/drivers/usb/core/hcd.c (revision 62e7ca52)
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/usb.h>
46 #include <linux/usb/hcd.h>
47 #include <linux/usb/phy.h>
48 
49 #include "usb.h"
50 
51 
52 /*-------------------------------------------------------------------------*/
53 
54 /*
55  * USB Host Controller Driver framework
56  *
57  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
58  * HCD-specific behaviors/bugs.
59  *
60  * This does error checks, tracks devices and urbs, and delegates to a
61  * "hc_driver" only for code (and data) that really needs to know about
62  * hardware differences.  That includes root hub registers, i/o queues,
63  * and so on ... but as little else as possible.
64  *
65  * Shared code includes most of the "root hub" code (these are emulated,
66  * though each HC's hardware works differently) and PCI glue, plus request
67  * tracking overhead.  The HCD code should only block on spinlocks or on
68  * hardware handshaking; blocking on software events (such as other kernel
69  * threads releasing resources, or completing actions) is all generic.
70  *
71  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
72  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
73  * only by the hub driver ... and that neither should be seen or used by
74  * usb client device drivers.
75  *
76  * Contributors of ideas or unattributed patches include: David Brownell,
77  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
78  *
79  * HISTORY:
80  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
81  *		associated cleanup.  "usb_hcd" still != "usb_bus".
82  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
83  */
84 
85 /*-------------------------------------------------------------------------*/
86 
87 /* Keep track of which host controller drivers are loaded */
88 unsigned long usb_hcds_loaded;
89 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
90 
91 /* host controllers we manage */
92 LIST_HEAD (usb_bus_list);
93 EXPORT_SYMBOL_GPL (usb_bus_list);
94 
95 /* used when allocating bus numbers */
96 #define USB_MAXBUS		64
97 static DECLARE_BITMAP(busmap, USB_MAXBUS);
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 #define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
128 #define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
129 
130 /* usb 3.0 root hub device descriptor */
131 static const u8 usb3_rh_dev_descriptor[18] = {
132 	0x12,       /*  __u8  bLength; */
133 	0x01,       /*  __u8  bDescriptorType; Device */
134 	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
135 
136 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
137 	0x00,	    /*  __u8  bDeviceSubClass; */
138 	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
139 	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
140 
141 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
142 	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
143 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
144 
145 	0x03,       /*  __u8  iManufacturer; */
146 	0x02,       /*  __u8  iProduct; */
147 	0x01,       /*  __u8  iSerialNumber; */
148 	0x01        /*  __u8  bNumConfigurations; */
149 };
150 
151 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
152 static const u8 usb25_rh_dev_descriptor[18] = {
153 	0x12,       /*  __u8  bLength; */
154 	0x01,       /*  __u8  bDescriptorType; Device */
155 	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
156 
157 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
158 	0x00,	    /*  __u8  bDeviceSubClass; */
159 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
160 	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
161 
162 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
163 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
164 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
165 
166 	0x03,       /*  __u8  iManufacturer; */
167 	0x02,       /*  __u8  iProduct; */
168 	0x01,       /*  __u8  iSerialNumber; */
169 	0x01        /*  __u8  bNumConfigurations; */
170 };
171 
172 /* usb 2.0 root hub device descriptor */
173 static const u8 usb2_rh_dev_descriptor[18] = {
174 	0x12,       /*  __u8  bLength; */
175 	0x01,       /*  __u8  bDescriptorType; Device */
176 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
177 
178 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
179 	0x00,	    /*  __u8  bDeviceSubClass; */
180 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
181 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
182 
183 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
184 	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
185 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
186 
187 	0x03,       /*  __u8  iManufacturer; */
188 	0x02,       /*  __u8  iProduct; */
189 	0x01,       /*  __u8  iSerialNumber; */
190 	0x01        /*  __u8  bNumConfigurations; */
191 };
192 
193 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
194 
195 /* usb 1.1 root hub device descriptor */
196 static const u8 usb11_rh_dev_descriptor[18] = {
197 	0x12,       /*  __u8  bLength; */
198 	0x01,       /*  __u8  bDescriptorType; Device */
199 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
200 
201 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
202 	0x00,	    /*  __u8  bDeviceSubClass; */
203 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
204 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
205 
206 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
207 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
208 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
209 
210 	0x03,       /*  __u8  iManufacturer; */
211 	0x02,       /*  __u8  iProduct; */
212 	0x01,       /*  __u8  iSerialNumber; */
213 	0x01        /*  __u8  bNumConfigurations; */
214 };
215 
216 
217 /*-------------------------------------------------------------------------*/
218 
219 /* Configuration descriptors for our root hubs */
220 
221 static const u8 fs_rh_config_descriptor[] = {
222 
223 	/* one configuration */
224 	0x09,       /*  __u8  bLength; */
225 	0x02,       /*  __u8  bDescriptorType; Configuration */
226 	0x19, 0x00, /*  __le16 wTotalLength; */
227 	0x01,       /*  __u8  bNumInterfaces; (1) */
228 	0x01,       /*  __u8  bConfigurationValue; */
229 	0x00,       /*  __u8  iConfiguration; */
230 	0xc0,       /*  __u8  bmAttributes;
231 				 Bit 7: must be set,
232 				     6: Self-powered,
233 				     5: Remote wakeup,
234 				     4..0: resvd */
235 	0x00,       /*  __u8  MaxPower; */
236 
237 	/* USB 1.1:
238 	 * USB 2.0, single TT organization (mandatory):
239 	 *	one interface, protocol 0
240 	 *
241 	 * USB 2.0, multiple TT organization (optional):
242 	 *	two interfaces, protocols 1 (like single TT)
243 	 *	and 2 (multiple TT mode) ... config is
244 	 *	sometimes settable
245 	 *	NOT IMPLEMENTED
246 	 */
247 
248 	/* one interface */
249 	0x09,       /*  __u8  if_bLength; */
250 	0x04,       /*  __u8  if_bDescriptorType; Interface */
251 	0x00,       /*  __u8  if_bInterfaceNumber; */
252 	0x00,       /*  __u8  if_bAlternateSetting; */
253 	0x01,       /*  __u8  if_bNumEndpoints; */
254 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
255 	0x00,       /*  __u8  if_bInterfaceSubClass; */
256 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
257 	0x00,       /*  __u8  if_iInterface; */
258 
259 	/* one endpoint (status change endpoint) */
260 	0x07,       /*  __u8  ep_bLength; */
261 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
262 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
263 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
264 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
265 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
266 };
267 
268 static const u8 hs_rh_config_descriptor[] = {
269 
270 	/* one configuration */
271 	0x09,       /*  __u8  bLength; */
272 	0x02,       /*  __u8  bDescriptorType; Configuration */
273 	0x19, 0x00, /*  __le16 wTotalLength; */
274 	0x01,       /*  __u8  bNumInterfaces; (1) */
275 	0x01,       /*  __u8  bConfigurationValue; */
276 	0x00,       /*  __u8  iConfiguration; */
277 	0xc0,       /*  __u8  bmAttributes;
278 				 Bit 7: must be set,
279 				     6: Self-powered,
280 				     5: Remote wakeup,
281 				     4..0: resvd */
282 	0x00,       /*  __u8  MaxPower; */
283 
284 	/* USB 1.1:
285 	 * USB 2.0, single TT organization (mandatory):
286 	 *	one interface, protocol 0
287 	 *
288 	 * USB 2.0, multiple TT organization (optional):
289 	 *	two interfaces, protocols 1 (like single TT)
290 	 *	and 2 (multiple TT mode) ... config is
291 	 *	sometimes settable
292 	 *	NOT IMPLEMENTED
293 	 */
294 
295 	/* one interface */
296 	0x09,       /*  __u8  if_bLength; */
297 	0x04,       /*  __u8  if_bDescriptorType; Interface */
298 	0x00,       /*  __u8  if_bInterfaceNumber; */
299 	0x00,       /*  __u8  if_bAlternateSetting; */
300 	0x01,       /*  __u8  if_bNumEndpoints; */
301 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
302 	0x00,       /*  __u8  if_bInterfaceSubClass; */
303 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
304 	0x00,       /*  __u8  if_iInterface; */
305 
306 	/* one endpoint (status change endpoint) */
307 	0x07,       /*  __u8  ep_bLength; */
308 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
309 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
310 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
311 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
312 		     * see hub.c:hub_configure() for details. */
313 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
314 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
315 };
316 
317 static const u8 ss_rh_config_descriptor[] = {
318 	/* one configuration */
319 	0x09,       /*  __u8  bLength; */
320 	0x02,       /*  __u8  bDescriptorType; Configuration */
321 	0x1f, 0x00, /*  __le16 wTotalLength; */
322 	0x01,       /*  __u8  bNumInterfaces; (1) */
323 	0x01,       /*  __u8  bConfigurationValue; */
324 	0x00,       /*  __u8  iConfiguration; */
325 	0xc0,       /*  __u8  bmAttributes;
326 				 Bit 7: must be set,
327 				     6: Self-powered,
328 				     5: Remote wakeup,
329 				     4..0: resvd */
330 	0x00,       /*  __u8  MaxPower; */
331 
332 	/* one interface */
333 	0x09,       /*  __u8  if_bLength; */
334 	0x04,       /*  __u8  if_bDescriptorType; Interface */
335 	0x00,       /*  __u8  if_bInterfaceNumber; */
336 	0x00,       /*  __u8  if_bAlternateSetting; */
337 	0x01,       /*  __u8  if_bNumEndpoints; */
338 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
339 	0x00,       /*  __u8  if_bInterfaceSubClass; */
340 	0x00,       /*  __u8  if_bInterfaceProtocol; */
341 	0x00,       /*  __u8  if_iInterface; */
342 
343 	/* one endpoint (status change endpoint) */
344 	0x07,       /*  __u8  ep_bLength; */
345 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
346 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
347 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
348 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
349 		     * see hub.c:hub_configure() for details. */
350 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
351 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
352 
353 	/* one SuperSpeed endpoint companion descriptor */
354 	0x06,        /* __u8 ss_bLength */
355 	0x30,        /* __u8 ss_bDescriptorType; SuperSpeed EP Companion */
356 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
357 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
358 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
359 };
360 
361 /* authorized_default behaviour:
362  * -1 is authorized for all devices except wireless (old behaviour)
363  * 0 is unauthorized for all devices
364  * 1 is authorized for all devices
365  */
366 static int authorized_default = -1;
367 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
368 MODULE_PARM_DESC(authorized_default,
369 		"Default USB device authorization: 0 is not authorized, 1 is "
370 		"authorized, -1 is authorized except for wireless USB (default, "
371 		"old behaviour");
372 /*-------------------------------------------------------------------------*/
373 
374 /**
375  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
376  * @s: Null-terminated ASCII (actually ISO-8859-1) string
377  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
378  * @len: Length (in bytes; may be odd) of descriptor buffer.
379  *
380  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
381  * whichever is less.
382  *
383  * Note:
384  * USB String descriptors can contain at most 126 characters; input
385  * strings longer than that are truncated.
386  */
387 static unsigned
388 ascii2desc(char const *s, u8 *buf, unsigned len)
389 {
390 	unsigned n, t = 2 + 2*strlen(s);
391 
392 	if (t > 254)
393 		t = 254;	/* Longest possible UTF string descriptor */
394 	if (len > t)
395 		len = t;
396 
397 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
398 
399 	n = len;
400 	while (n--) {
401 		*buf++ = t;
402 		if (!n--)
403 			break;
404 		*buf++ = t >> 8;
405 		t = (unsigned char)*s++;
406 	}
407 	return len;
408 }
409 
410 /**
411  * rh_string() - provides string descriptors for root hub
412  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
413  * @hcd: the host controller for this root hub
414  * @data: buffer for output packet
415  * @len: length of the provided buffer
416  *
417  * Produces either a manufacturer, product or serial number string for the
418  * virtual root hub device.
419  *
420  * Return: The number of bytes filled in: the length of the descriptor or
421  * of the provided buffer, whichever is less.
422  */
423 static unsigned
424 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
425 {
426 	char buf[100];
427 	char const *s;
428 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
429 
430 	/* language ids */
431 	switch (id) {
432 	case 0:
433 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
434 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
435 		if (len > 4)
436 			len = 4;
437 		memcpy(data, langids, len);
438 		return len;
439 	case 1:
440 		/* Serial number */
441 		s = hcd->self.bus_name;
442 		break;
443 	case 2:
444 		/* Product name */
445 		s = hcd->product_desc;
446 		break;
447 	case 3:
448 		/* Manufacturer */
449 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
450 			init_utsname()->release, hcd->driver->description);
451 		s = buf;
452 		break;
453 	default:
454 		/* Can't happen; caller guarantees it */
455 		return 0;
456 	}
457 
458 	return ascii2desc(s, data, len);
459 }
460 
461 
462 /* Root hub control transfers execute synchronously */
463 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
464 {
465 	struct usb_ctrlrequest *cmd;
466 	u16		typeReq, wValue, wIndex, wLength;
467 	u8		*ubuf = urb->transfer_buffer;
468 	unsigned	len = 0;
469 	int		status;
470 	u8		patch_wakeup = 0;
471 	u8		patch_protocol = 0;
472 	u16		tbuf_size;
473 	u8		*tbuf = NULL;
474 	const u8	*bufp;
475 
476 	might_sleep();
477 
478 	spin_lock_irq(&hcd_root_hub_lock);
479 	status = usb_hcd_link_urb_to_ep(hcd, urb);
480 	spin_unlock_irq(&hcd_root_hub_lock);
481 	if (status)
482 		return status;
483 	urb->hcpriv = hcd;	/* Indicate it's queued */
484 
485 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
486 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
487 	wValue   = le16_to_cpu (cmd->wValue);
488 	wIndex   = le16_to_cpu (cmd->wIndex);
489 	wLength  = le16_to_cpu (cmd->wLength);
490 
491 	if (wLength > urb->transfer_buffer_length)
492 		goto error;
493 
494 	/*
495 	 * tbuf should be at least as big as the
496 	 * USB hub descriptor.
497 	 */
498 	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
499 	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
500 	if (!tbuf)
501 		return -ENOMEM;
502 
503 	bufp = tbuf;
504 
505 
506 	urb->actual_length = 0;
507 	switch (typeReq) {
508 
509 	/* DEVICE REQUESTS */
510 
511 	/* The root hub's remote wakeup enable bit is implemented using
512 	 * driver model wakeup flags.  If this system supports wakeup
513 	 * through USB, userspace may change the default "allow wakeup"
514 	 * policy through sysfs or these calls.
515 	 *
516 	 * Most root hubs support wakeup from downstream devices, for
517 	 * runtime power management (disabling USB clocks and reducing
518 	 * VBUS power usage).  However, not all of them do so; silicon,
519 	 * board, and BIOS bugs here are not uncommon, so these can't
520 	 * be treated quite like external hubs.
521 	 *
522 	 * Likewise, not all root hubs will pass wakeup events upstream,
523 	 * to wake up the whole system.  So don't assume root hub and
524 	 * controller capabilities are identical.
525 	 */
526 
527 	case DeviceRequest | USB_REQ_GET_STATUS:
528 		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
529 					<< USB_DEVICE_REMOTE_WAKEUP)
530 				| (1 << USB_DEVICE_SELF_POWERED);
531 		tbuf[1] = 0;
532 		len = 2;
533 		break;
534 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
535 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
536 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
537 		else
538 			goto error;
539 		break;
540 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
541 		if (device_can_wakeup(&hcd->self.root_hub->dev)
542 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
543 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
544 		else
545 			goto error;
546 		break;
547 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
548 		tbuf[0] = 1;
549 		len = 1;
550 			/* FALLTHROUGH */
551 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
552 		break;
553 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
554 		switch (wValue & 0xff00) {
555 		case USB_DT_DEVICE << 8:
556 			switch (hcd->speed) {
557 			case HCD_USB3:
558 				bufp = usb3_rh_dev_descriptor;
559 				break;
560 			case HCD_USB25:
561 				bufp = usb25_rh_dev_descriptor;
562 				break;
563 			case HCD_USB2:
564 				bufp = usb2_rh_dev_descriptor;
565 				break;
566 			case HCD_USB11:
567 				bufp = usb11_rh_dev_descriptor;
568 				break;
569 			default:
570 				goto error;
571 			}
572 			len = 18;
573 			if (hcd->has_tt)
574 				patch_protocol = 1;
575 			break;
576 		case USB_DT_CONFIG << 8:
577 			switch (hcd->speed) {
578 			case HCD_USB3:
579 				bufp = ss_rh_config_descriptor;
580 				len = sizeof ss_rh_config_descriptor;
581 				break;
582 			case HCD_USB25:
583 			case HCD_USB2:
584 				bufp = hs_rh_config_descriptor;
585 				len = sizeof hs_rh_config_descriptor;
586 				break;
587 			case HCD_USB11:
588 				bufp = fs_rh_config_descriptor;
589 				len = sizeof fs_rh_config_descriptor;
590 				break;
591 			default:
592 				goto error;
593 			}
594 			if (device_can_wakeup(&hcd->self.root_hub->dev))
595 				patch_wakeup = 1;
596 			break;
597 		case USB_DT_STRING << 8:
598 			if ((wValue & 0xff) < 4)
599 				urb->actual_length = rh_string(wValue & 0xff,
600 						hcd, ubuf, wLength);
601 			else /* unsupported IDs --> "protocol stall" */
602 				goto error;
603 			break;
604 		case USB_DT_BOS << 8:
605 			goto nongeneric;
606 		default:
607 			goto error;
608 		}
609 		break;
610 	case DeviceRequest | USB_REQ_GET_INTERFACE:
611 		tbuf[0] = 0;
612 		len = 1;
613 			/* FALLTHROUGH */
614 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
615 		break;
616 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
617 		/* wValue == urb->dev->devaddr */
618 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
619 			wValue);
620 		break;
621 
622 	/* INTERFACE REQUESTS (no defined feature/status flags) */
623 
624 	/* ENDPOINT REQUESTS */
625 
626 	case EndpointRequest | USB_REQ_GET_STATUS:
627 		/* ENDPOINT_HALT flag */
628 		tbuf[0] = 0;
629 		tbuf[1] = 0;
630 		len = 2;
631 			/* FALLTHROUGH */
632 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
633 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
634 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
635 		break;
636 
637 	/* CLASS REQUESTS (and errors) */
638 
639 	default:
640 nongeneric:
641 		/* non-generic request */
642 		switch (typeReq) {
643 		case GetHubStatus:
644 		case GetPortStatus:
645 			len = 4;
646 			break;
647 		case GetHubDescriptor:
648 			len = sizeof (struct usb_hub_descriptor);
649 			break;
650 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
651 			/* len is returned by hub_control */
652 			break;
653 		}
654 		status = hcd->driver->hub_control (hcd,
655 			typeReq, wValue, wIndex,
656 			tbuf, wLength);
657 
658 		if (typeReq == GetHubDescriptor)
659 			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
660 				(struct usb_hub_descriptor *)tbuf);
661 		break;
662 error:
663 		/* "protocol stall" on error */
664 		status = -EPIPE;
665 	}
666 
667 	if (status < 0) {
668 		len = 0;
669 		if (status != -EPIPE) {
670 			dev_dbg (hcd->self.controller,
671 				"CTRL: TypeReq=0x%x val=0x%x "
672 				"idx=0x%x len=%d ==> %d\n",
673 				typeReq, wValue, wIndex,
674 				wLength, status);
675 		}
676 	} else if (status > 0) {
677 		/* hub_control may return the length of data copied. */
678 		len = status;
679 		status = 0;
680 	}
681 	if (len) {
682 		if (urb->transfer_buffer_length < len)
683 			len = urb->transfer_buffer_length;
684 		urb->actual_length = len;
685 		/* always USB_DIR_IN, toward host */
686 		memcpy (ubuf, bufp, len);
687 
688 		/* report whether RH hardware supports remote wakeup */
689 		if (patch_wakeup &&
690 				len > offsetof (struct usb_config_descriptor,
691 						bmAttributes))
692 			((struct usb_config_descriptor *)ubuf)->bmAttributes
693 				|= USB_CONFIG_ATT_WAKEUP;
694 
695 		/* report whether RH hardware has an integrated TT */
696 		if (patch_protocol &&
697 				len > offsetof(struct usb_device_descriptor,
698 						bDeviceProtocol))
699 			((struct usb_device_descriptor *) ubuf)->
700 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
701 	}
702 
703 	kfree(tbuf);
704 
705 	/* any errors get returned through the urb completion */
706 	spin_lock_irq(&hcd_root_hub_lock);
707 	usb_hcd_unlink_urb_from_ep(hcd, urb);
708 	usb_hcd_giveback_urb(hcd, urb, status);
709 	spin_unlock_irq(&hcd_root_hub_lock);
710 	return 0;
711 }
712 
713 /*-------------------------------------------------------------------------*/
714 
715 /*
716  * Root Hub interrupt transfers are polled using a timer if the
717  * driver requests it; otherwise the driver is responsible for
718  * calling usb_hcd_poll_rh_status() when an event occurs.
719  *
720  * Completions are called in_interrupt(), but they may or may not
721  * be in_irq().
722  */
723 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
724 {
725 	struct urb	*urb;
726 	int		length;
727 	unsigned long	flags;
728 	char		buffer[6];	/* Any root hubs with > 31 ports? */
729 
730 	if (unlikely(!hcd->rh_pollable))
731 		return;
732 	if (!hcd->uses_new_polling && !hcd->status_urb)
733 		return;
734 
735 	length = hcd->driver->hub_status_data(hcd, buffer);
736 	if (length > 0) {
737 
738 		/* try to complete the status urb */
739 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
740 		urb = hcd->status_urb;
741 		if (urb) {
742 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
743 			hcd->status_urb = NULL;
744 			urb->actual_length = length;
745 			memcpy(urb->transfer_buffer, buffer, length);
746 
747 			usb_hcd_unlink_urb_from_ep(hcd, urb);
748 			usb_hcd_giveback_urb(hcd, urb, 0);
749 		} else {
750 			length = 0;
751 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
752 		}
753 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
754 	}
755 
756 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
757 	 * exceed that limit if HZ is 100. The math is more clunky than
758 	 * maybe expected, this is to make sure that all timers for USB devices
759 	 * fire at the same time to give the CPU a break in between */
760 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
761 			(length == 0 && hcd->status_urb != NULL))
762 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
763 }
764 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
765 
766 /* timer callback */
767 static void rh_timer_func (unsigned long _hcd)
768 {
769 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
770 }
771 
772 /*-------------------------------------------------------------------------*/
773 
774 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
775 {
776 	int		retval;
777 	unsigned long	flags;
778 	unsigned	len = 1 + (urb->dev->maxchild / 8);
779 
780 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
781 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
782 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
783 		retval = -EINVAL;
784 		goto done;
785 	}
786 
787 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
788 	if (retval)
789 		goto done;
790 
791 	hcd->status_urb = urb;
792 	urb->hcpriv = hcd;	/* indicate it's queued */
793 	if (!hcd->uses_new_polling)
794 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
795 
796 	/* If a status change has already occurred, report it ASAP */
797 	else if (HCD_POLL_PENDING(hcd))
798 		mod_timer(&hcd->rh_timer, jiffies);
799 	retval = 0;
800  done:
801 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
802 	return retval;
803 }
804 
805 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
806 {
807 	if (usb_endpoint_xfer_int(&urb->ep->desc))
808 		return rh_queue_status (hcd, urb);
809 	if (usb_endpoint_xfer_control(&urb->ep->desc))
810 		return rh_call_control (hcd, urb);
811 	return -EINVAL;
812 }
813 
814 /*-------------------------------------------------------------------------*/
815 
816 /* Unlinks of root-hub control URBs are legal, but they don't do anything
817  * since these URBs always execute synchronously.
818  */
819 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
820 {
821 	unsigned long	flags;
822 	int		rc;
823 
824 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
825 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
826 	if (rc)
827 		goto done;
828 
829 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
830 		;	/* Do nothing */
831 
832 	} else {				/* Status URB */
833 		if (!hcd->uses_new_polling)
834 			del_timer (&hcd->rh_timer);
835 		if (urb == hcd->status_urb) {
836 			hcd->status_urb = NULL;
837 			usb_hcd_unlink_urb_from_ep(hcd, urb);
838 			usb_hcd_giveback_urb(hcd, urb, status);
839 		}
840 	}
841  done:
842 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
843 	return rc;
844 }
845 
846 
847 
848 /*
849  * Show & store the current value of authorized_default
850  */
851 static ssize_t authorized_default_show(struct device *dev,
852 				       struct device_attribute *attr, char *buf)
853 {
854 	struct usb_device *rh_usb_dev = to_usb_device(dev);
855 	struct usb_bus *usb_bus = rh_usb_dev->bus;
856 	struct usb_hcd *usb_hcd;
857 
858 	usb_hcd = bus_to_hcd(usb_bus);
859 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
860 }
861 
862 static ssize_t authorized_default_store(struct device *dev,
863 					struct device_attribute *attr,
864 					const char *buf, size_t size)
865 {
866 	ssize_t result;
867 	unsigned val;
868 	struct usb_device *rh_usb_dev = to_usb_device(dev);
869 	struct usb_bus *usb_bus = rh_usb_dev->bus;
870 	struct usb_hcd *usb_hcd;
871 
872 	usb_hcd = bus_to_hcd(usb_bus);
873 	result = sscanf(buf, "%u\n", &val);
874 	if (result == 1) {
875 		usb_hcd->authorized_default = val ? 1 : 0;
876 		result = size;
877 	} else {
878 		result = -EINVAL;
879 	}
880 	return result;
881 }
882 static DEVICE_ATTR_RW(authorized_default);
883 
884 /* Group all the USB bus attributes */
885 static struct attribute *usb_bus_attrs[] = {
886 		&dev_attr_authorized_default.attr,
887 		NULL,
888 };
889 
890 static struct attribute_group usb_bus_attr_group = {
891 	.name = NULL,	/* we want them in the same directory */
892 	.attrs = usb_bus_attrs,
893 };
894 
895 
896 
897 /*-------------------------------------------------------------------------*/
898 
899 /**
900  * usb_bus_init - shared initialization code
901  * @bus: the bus structure being initialized
902  *
903  * This code is used to initialize a usb_bus structure, memory for which is
904  * separately managed.
905  */
906 static void usb_bus_init (struct usb_bus *bus)
907 {
908 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
909 
910 	bus->devnum_next = 1;
911 
912 	bus->root_hub = NULL;
913 	bus->busnum = -1;
914 	bus->bandwidth_allocated = 0;
915 	bus->bandwidth_int_reqs  = 0;
916 	bus->bandwidth_isoc_reqs = 0;
917 	mutex_init(&bus->usb_address0_mutex);
918 
919 	INIT_LIST_HEAD (&bus->bus_list);
920 }
921 
922 /*-------------------------------------------------------------------------*/
923 
924 /**
925  * usb_register_bus - registers the USB host controller with the usb core
926  * @bus: pointer to the bus to register
927  * Context: !in_interrupt()
928  *
929  * Assigns a bus number, and links the controller into usbcore data
930  * structures so that it can be seen by scanning the bus list.
931  *
932  * Return: 0 if successful. A negative error code otherwise.
933  */
934 static int usb_register_bus(struct usb_bus *bus)
935 {
936 	int result = -E2BIG;
937 	int busnum;
938 
939 	mutex_lock(&usb_bus_list_lock);
940 	busnum = find_next_zero_bit(busmap, USB_MAXBUS, 1);
941 	if (busnum >= USB_MAXBUS) {
942 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
943 		goto error_find_busnum;
944 	}
945 	set_bit(busnum, busmap);
946 	bus->busnum = busnum;
947 
948 	/* Add it to the local list of buses */
949 	list_add (&bus->bus_list, &usb_bus_list);
950 	mutex_unlock(&usb_bus_list_lock);
951 
952 	usb_notify_add_bus(bus);
953 
954 	dev_info (bus->controller, "new USB bus registered, assigned bus "
955 		  "number %d\n", bus->busnum);
956 	return 0;
957 
958 error_find_busnum:
959 	mutex_unlock(&usb_bus_list_lock);
960 	return result;
961 }
962 
963 /**
964  * usb_deregister_bus - deregisters the USB host controller
965  * @bus: pointer to the bus to deregister
966  * Context: !in_interrupt()
967  *
968  * Recycles the bus number, and unlinks the controller from usbcore data
969  * structures so that it won't be seen by scanning the bus list.
970  */
971 static void usb_deregister_bus (struct usb_bus *bus)
972 {
973 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
974 
975 	/*
976 	 * NOTE: make sure that all the devices are removed by the
977 	 * controller code, as well as having it call this when cleaning
978 	 * itself up
979 	 */
980 	mutex_lock(&usb_bus_list_lock);
981 	list_del (&bus->bus_list);
982 	mutex_unlock(&usb_bus_list_lock);
983 
984 	usb_notify_remove_bus(bus);
985 
986 	clear_bit(bus->busnum, busmap);
987 }
988 
989 /**
990  * register_root_hub - called by usb_add_hcd() to register a root hub
991  * @hcd: host controller for this root hub
992  *
993  * This function registers the root hub with the USB subsystem.  It sets up
994  * the device properly in the device tree and then calls usb_new_device()
995  * to register the usb device.  It also assigns the root hub's USB address
996  * (always 1).
997  *
998  * Return: 0 if successful. A negative error code otherwise.
999  */
1000 static int register_root_hub(struct usb_hcd *hcd)
1001 {
1002 	struct device *parent_dev = hcd->self.controller;
1003 	struct usb_device *usb_dev = hcd->self.root_hub;
1004 	const int devnum = 1;
1005 	int retval;
1006 
1007 	usb_dev->devnum = devnum;
1008 	usb_dev->bus->devnum_next = devnum + 1;
1009 	memset (&usb_dev->bus->devmap.devicemap, 0,
1010 			sizeof usb_dev->bus->devmap.devicemap);
1011 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
1012 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1013 
1014 	mutex_lock(&usb_bus_list_lock);
1015 
1016 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1017 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1018 	if (retval != sizeof usb_dev->descriptor) {
1019 		mutex_unlock(&usb_bus_list_lock);
1020 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1021 				dev_name(&usb_dev->dev), retval);
1022 		return (retval < 0) ? retval : -EMSGSIZE;
1023 	}
1024 	if (usb_dev->speed == USB_SPEED_SUPER) {
1025 		retval = usb_get_bos_descriptor(usb_dev);
1026 		if (retval < 0) {
1027 			mutex_unlock(&usb_bus_list_lock);
1028 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1029 					dev_name(&usb_dev->dev), retval);
1030 			return retval;
1031 		}
1032 	}
1033 
1034 	retval = usb_new_device (usb_dev);
1035 	if (retval) {
1036 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1037 				dev_name(&usb_dev->dev), retval);
1038 	} else {
1039 		spin_lock_irq (&hcd_root_hub_lock);
1040 		hcd->rh_registered = 1;
1041 		spin_unlock_irq (&hcd_root_hub_lock);
1042 
1043 		/* Did the HC die before the root hub was registered? */
1044 		if (HCD_DEAD(hcd))
1045 			usb_hc_died (hcd);	/* This time clean up */
1046 	}
1047 	mutex_unlock(&usb_bus_list_lock);
1048 
1049 	return retval;
1050 }
1051 
1052 /*
1053  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1054  * @bus: the bus which the root hub belongs to
1055  * @portnum: the port which is being resumed
1056  *
1057  * HCDs should call this function when they know that a resume signal is
1058  * being sent to a root-hub port.  The root hub will be prevented from
1059  * going into autosuspend until usb_hcd_end_port_resume() is called.
1060  *
1061  * The bus's private lock must be held by the caller.
1062  */
1063 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1064 {
1065 	unsigned bit = 1 << portnum;
1066 
1067 	if (!(bus->resuming_ports & bit)) {
1068 		bus->resuming_ports |= bit;
1069 		pm_runtime_get_noresume(&bus->root_hub->dev);
1070 	}
1071 }
1072 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1073 
1074 /*
1075  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1076  * @bus: the bus which the root hub belongs to
1077  * @portnum: the port which is being resumed
1078  *
1079  * HCDs should call this function when they know that a resume signal has
1080  * stopped being sent to a root-hub port.  The root hub will be allowed to
1081  * autosuspend again.
1082  *
1083  * The bus's private lock must be held by the caller.
1084  */
1085 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1086 {
1087 	unsigned bit = 1 << portnum;
1088 
1089 	if (bus->resuming_ports & bit) {
1090 		bus->resuming_ports &= ~bit;
1091 		pm_runtime_put_noidle(&bus->root_hub->dev);
1092 	}
1093 }
1094 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1095 
1096 /*-------------------------------------------------------------------------*/
1097 
1098 /**
1099  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1100  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1101  * @is_input: true iff the transaction sends data to the host
1102  * @isoc: true for isochronous transactions, false for interrupt ones
1103  * @bytecount: how many bytes in the transaction.
1104  *
1105  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1106  *
1107  * Note:
1108  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1109  * scheduled in software, this function is only used for such scheduling.
1110  */
1111 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1112 {
1113 	unsigned long	tmp;
1114 
1115 	switch (speed) {
1116 	case USB_SPEED_LOW: 	/* INTR only */
1117 		if (is_input) {
1118 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1119 			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1120 		} else {
1121 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1122 			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1123 		}
1124 	case USB_SPEED_FULL:	/* ISOC or INTR */
1125 		if (isoc) {
1126 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1127 			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1128 		} else {
1129 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1130 			return 9107L + BW_HOST_DELAY + tmp;
1131 		}
1132 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1133 		/* FIXME adjust for input vs output */
1134 		if (isoc)
1135 			tmp = HS_NSECS_ISO (bytecount);
1136 		else
1137 			tmp = HS_NSECS (bytecount);
1138 		return tmp;
1139 	default:
1140 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1141 		return -1;
1142 	}
1143 }
1144 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1145 
1146 
1147 /*-------------------------------------------------------------------------*/
1148 
1149 /*
1150  * Generic HC operations.
1151  */
1152 
1153 /*-------------------------------------------------------------------------*/
1154 
1155 /**
1156  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1157  * @hcd: host controller to which @urb was submitted
1158  * @urb: URB being submitted
1159  *
1160  * Host controller drivers should call this routine in their enqueue()
1161  * method.  The HCD's private spinlock must be held and interrupts must
1162  * be disabled.  The actions carried out here are required for URB
1163  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1164  *
1165  * Return: 0 for no error, otherwise a negative error code (in which case
1166  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1167  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1168  * the private spinlock and returning.
1169  */
1170 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1171 {
1172 	int		rc = 0;
1173 
1174 	spin_lock(&hcd_urb_list_lock);
1175 
1176 	/* Check that the URB isn't being killed */
1177 	if (unlikely(atomic_read(&urb->reject))) {
1178 		rc = -EPERM;
1179 		goto done;
1180 	}
1181 
1182 	if (unlikely(!urb->ep->enabled)) {
1183 		rc = -ENOENT;
1184 		goto done;
1185 	}
1186 
1187 	if (unlikely(!urb->dev->can_submit)) {
1188 		rc = -EHOSTUNREACH;
1189 		goto done;
1190 	}
1191 
1192 	/*
1193 	 * Check the host controller's state and add the URB to the
1194 	 * endpoint's queue.
1195 	 */
1196 	if (HCD_RH_RUNNING(hcd)) {
1197 		urb->unlinked = 0;
1198 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1199 	} else {
1200 		rc = -ESHUTDOWN;
1201 		goto done;
1202 	}
1203  done:
1204 	spin_unlock(&hcd_urb_list_lock);
1205 	return rc;
1206 }
1207 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1208 
1209 /**
1210  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1211  * @hcd: host controller to which @urb was submitted
1212  * @urb: URB being checked for unlinkability
1213  * @status: error code to store in @urb if the unlink succeeds
1214  *
1215  * Host controller drivers should call this routine in their dequeue()
1216  * method.  The HCD's private spinlock must be held and interrupts must
1217  * be disabled.  The actions carried out here are required for making
1218  * sure than an unlink is valid.
1219  *
1220  * Return: 0 for no error, otherwise a negative error code (in which case
1221  * the dequeue() method must fail).  The possible error codes are:
1222  *
1223  *	-EIDRM: @urb was not submitted or has already completed.
1224  *		The completion function may not have been called yet.
1225  *
1226  *	-EBUSY: @urb has already been unlinked.
1227  */
1228 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1229 		int status)
1230 {
1231 	struct list_head	*tmp;
1232 
1233 	/* insist the urb is still queued */
1234 	list_for_each(tmp, &urb->ep->urb_list) {
1235 		if (tmp == &urb->urb_list)
1236 			break;
1237 	}
1238 	if (tmp != &urb->urb_list)
1239 		return -EIDRM;
1240 
1241 	/* Any status except -EINPROGRESS means something already started to
1242 	 * unlink this URB from the hardware.  So there's no more work to do.
1243 	 */
1244 	if (urb->unlinked)
1245 		return -EBUSY;
1246 	urb->unlinked = status;
1247 	return 0;
1248 }
1249 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1250 
1251 /**
1252  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1253  * @hcd: host controller to which @urb was submitted
1254  * @urb: URB being unlinked
1255  *
1256  * Host controller drivers should call this routine before calling
1257  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1258  * interrupts must be disabled.  The actions carried out here are required
1259  * for URB completion.
1260  */
1261 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1262 {
1263 	/* clear all state linking urb to this dev (and hcd) */
1264 	spin_lock(&hcd_urb_list_lock);
1265 	list_del_init(&urb->urb_list);
1266 	spin_unlock(&hcd_urb_list_lock);
1267 }
1268 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1269 
1270 /*
1271  * Some usb host controllers can only perform dma using a small SRAM area.
1272  * The usb core itself is however optimized for host controllers that can dma
1273  * using regular system memory - like pci devices doing bus mastering.
1274  *
1275  * To support host controllers with limited dma capabilites we provide dma
1276  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1277  * For this to work properly the host controller code must first use the
1278  * function dma_declare_coherent_memory() to point out which memory area
1279  * that should be used for dma allocations.
1280  *
1281  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1282  * dma using dma_alloc_coherent() which in turn allocates from the memory
1283  * area pointed out with dma_declare_coherent_memory().
1284  *
1285  * So, to summarize...
1286  *
1287  * - We need "local" memory, canonical example being
1288  *   a small SRAM on a discrete controller being the
1289  *   only memory that the controller can read ...
1290  *   (a) "normal" kernel memory is no good, and
1291  *   (b) there's not enough to share
1292  *
1293  * - The only *portable* hook for such stuff in the
1294  *   DMA framework is dma_declare_coherent_memory()
1295  *
1296  * - So we use that, even though the primary requirement
1297  *   is that the memory be "local" (hence addressable
1298  *   by that device), not "coherent".
1299  *
1300  */
1301 
1302 static int hcd_alloc_coherent(struct usb_bus *bus,
1303 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1304 			      void **vaddr_handle, size_t size,
1305 			      enum dma_data_direction dir)
1306 {
1307 	unsigned char *vaddr;
1308 
1309 	if (*vaddr_handle == NULL) {
1310 		WARN_ON_ONCE(1);
1311 		return -EFAULT;
1312 	}
1313 
1314 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1315 				 mem_flags, dma_handle);
1316 	if (!vaddr)
1317 		return -ENOMEM;
1318 
1319 	/*
1320 	 * Store the virtual address of the buffer at the end
1321 	 * of the allocated dma buffer. The size of the buffer
1322 	 * may be uneven so use unaligned functions instead
1323 	 * of just rounding up. It makes sense to optimize for
1324 	 * memory footprint over access speed since the amount
1325 	 * of memory available for dma may be limited.
1326 	 */
1327 	put_unaligned((unsigned long)*vaddr_handle,
1328 		      (unsigned long *)(vaddr + size));
1329 
1330 	if (dir == DMA_TO_DEVICE)
1331 		memcpy(vaddr, *vaddr_handle, size);
1332 
1333 	*vaddr_handle = vaddr;
1334 	return 0;
1335 }
1336 
1337 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1338 			      void **vaddr_handle, size_t size,
1339 			      enum dma_data_direction dir)
1340 {
1341 	unsigned char *vaddr = *vaddr_handle;
1342 
1343 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1344 
1345 	if (dir == DMA_FROM_DEVICE)
1346 		memcpy(vaddr, *vaddr_handle, size);
1347 
1348 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1349 
1350 	*vaddr_handle = vaddr;
1351 	*dma_handle = 0;
1352 }
1353 
1354 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1355 {
1356 	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1357 		dma_unmap_single(hcd->self.controller,
1358 				urb->setup_dma,
1359 				sizeof(struct usb_ctrlrequest),
1360 				DMA_TO_DEVICE);
1361 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1362 		hcd_free_coherent(urb->dev->bus,
1363 				&urb->setup_dma,
1364 				(void **) &urb->setup_packet,
1365 				sizeof(struct usb_ctrlrequest),
1366 				DMA_TO_DEVICE);
1367 
1368 	/* Make it safe to call this routine more than once */
1369 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1370 }
1371 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1372 
1373 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1374 {
1375 	if (hcd->driver->unmap_urb_for_dma)
1376 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1377 	else
1378 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1379 }
1380 
1381 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1382 {
1383 	enum dma_data_direction dir;
1384 
1385 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1386 
1387 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1388 	if (urb->transfer_flags & URB_DMA_MAP_SG)
1389 		dma_unmap_sg(hcd->self.controller,
1390 				urb->sg,
1391 				urb->num_sgs,
1392 				dir);
1393 	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1394 		dma_unmap_page(hcd->self.controller,
1395 				urb->transfer_dma,
1396 				urb->transfer_buffer_length,
1397 				dir);
1398 	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1399 		dma_unmap_single(hcd->self.controller,
1400 				urb->transfer_dma,
1401 				urb->transfer_buffer_length,
1402 				dir);
1403 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1404 		hcd_free_coherent(urb->dev->bus,
1405 				&urb->transfer_dma,
1406 				&urb->transfer_buffer,
1407 				urb->transfer_buffer_length,
1408 				dir);
1409 
1410 	/* Make it safe to call this routine more than once */
1411 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1412 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1413 }
1414 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1415 
1416 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1417 			   gfp_t mem_flags)
1418 {
1419 	if (hcd->driver->map_urb_for_dma)
1420 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1421 	else
1422 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1423 }
1424 
1425 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1426 			    gfp_t mem_flags)
1427 {
1428 	enum dma_data_direction dir;
1429 	int ret = 0;
1430 
1431 	/* Map the URB's buffers for DMA access.
1432 	 * Lower level HCD code should use *_dma exclusively,
1433 	 * unless it uses pio or talks to another transport,
1434 	 * or uses the provided scatter gather list for bulk.
1435 	 */
1436 
1437 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1438 		if (hcd->self.uses_pio_for_control)
1439 			return ret;
1440 		if (hcd->self.uses_dma) {
1441 			urb->setup_dma = dma_map_single(
1442 					hcd->self.controller,
1443 					urb->setup_packet,
1444 					sizeof(struct usb_ctrlrequest),
1445 					DMA_TO_DEVICE);
1446 			if (dma_mapping_error(hcd->self.controller,
1447 						urb->setup_dma))
1448 				return -EAGAIN;
1449 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1450 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1451 			ret = hcd_alloc_coherent(
1452 					urb->dev->bus, mem_flags,
1453 					&urb->setup_dma,
1454 					(void **)&urb->setup_packet,
1455 					sizeof(struct usb_ctrlrequest),
1456 					DMA_TO_DEVICE);
1457 			if (ret)
1458 				return ret;
1459 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1460 		}
1461 	}
1462 
1463 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1464 	if (urb->transfer_buffer_length != 0
1465 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1466 		if (hcd->self.uses_dma) {
1467 			if (urb->num_sgs) {
1468 				int n;
1469 
1470 				/* We don't support sg for isoc transfers ! */
1471 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1472 					WARN_ON(1);
1473 					return -EINVAL;
1474 				}
1475 
1476 				n = dma_map_sg(
1477 						hcd->self.controller,
1478 						urb->sg,
1479 						urb->num_sgs,
1480 						dir);
1481 				if (n <= 0)
1482 					ret = -EAGAIN;
1483 				else
1484 					urb->transfer_flags |= URB_DMA_MAP_SG;
1485 				urb->num_mapped_sgs = n;
1486 				if (n != urb->num_sgs)
1487 					urb->transfer_flags |=
1488 							URB_DMA_SG_COMBINED;
1489 			} else if (urb->sg) {
1490 				struct scatterlist *sg = urb->sg;
1491 				urb->transfer_dma = dma_map_page(
1492 						hcd->self.controller,
1493 						sg_page(sg),
1494 						sg->offset,
1495 						urb->transfer_buffer_length,
1496 						dir);
1497 				if (dma_mapping_error(hcd->self.controller,
1498 						urb->transfer_dma))
1499 					ret = -EAGAIN;
1500 				else
1501 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1502 			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1503 				WARN_ONCE(1, "transfer buffer not dma capable\n");
1504 				ret = -EAGAIN;
1505 			} else {
1506 				urb->transfer_dma = dma_map_single(
1507 						hcd->self.controller,
1508 						urb->transfer_buffer,
1509 						urb->transfer_buffer_length,
1510 						dir);
1511 				if (dma_mapping_error(hcd->self.controller,
1512 						urb->transfer_dma))
1513 					ret = -EAGAIN;
1514 				else
1515 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1516 			}
1517 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1518 			ret = hcd_alloc_coherent(
1519 					urb->dev->bus, mem_flags,
1520 					&urb->transfer_dma,
1521 					&urb->transfer_buffer,
1522 					urb->transfer_buffer_length,
1523 					dir);
1524 			if (ret == 0)
1525 				urb->transfer_flags |= URB_MAP_LOCAL;
1526 		}
1527 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1528 				URB_SETUP_MAP_LOCAL)))
1529 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1530 	}
1531 	return ret;
1532 }
1533 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1534 
1535 /*-------------------------------------------------------------------------*/
1536 
1537 /* may be called in any context with a valid urb->dev usecount
1538  * caller surrenders "ownership" of urb
1539  * expects usb_submit_urb() to have sanity checked and conditioned all
1540  * inputs in the urb
1541  */
1542 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1543 {
1544 	int			status;
1545 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1546 
1547 	/* increment urb's reference count as part of giving it to the HCD
1548 	 * (which will control it).  HCD guarantees that it either returns
1549 	 * an error or calls giveback(), but not both.
1550 	 */
1551 	usb_get_urb(urb);
1552 	atomic_inc(&urb->use_count);
1553 	atomic_inc(&urb->dev->urbnum);
1554 	usbmon_urb_submit(&hcd->self, urb);
1555 
1556 	/* NOTE requirements on root-hub callers (usbfs and the hub
1557 	 * driver, for now):  URBs' urb->transfer_buffer must be
1558 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1559 	 * they could clobber root hub response data.  Also, control
1560 	 * URBs must be submitted in process context with interrupts
1561 	 * enabled.
1562 	 */
1563 
1564 	if (is_root_hub(urb->dev)) {
1565 		status = rh_urb_enqueue(hcd, urb);
1566 	} else {
1567 		status = map_urb_for_dma(hcd, urb, mem_flags);
1568 		if (likely(status == 0)) {
1569 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1570 			if (unlikely(status))
1571 				unmap_urb_for_dma(hcd, urb);
1572 		}
1573 	}
1574 
1575 	if (unlikely(status)) {
1576 		usbmon_urb_submit_error(&hcd->self, urb, status);
1577 		urb->hcpriv = NULL;
1578 		INIT_LIST_HEAD(&urb->urb_list);
1579 		atomic_dec(&urb->use_count);
1580 		atomic_dec(&urb->dev->urbnum);
1581 		if (atomic_read(&urb->reject))
1582 			wake_up(&usb_kill_urb_queue);
1583 		usb_put_urb(urb);
1584 	}
1585 	return status;
1586 }
1587 
1588 /*-------------------------------------------------------------------------*/
1589 
1590 /* this makes the hcd giveback() the urb more quickly, by kicking it
1591  * off hardware queues (which may take a while) and returning it as
1592  * soon as practical.  we've already set up the urb's return status,
1593  * but we can't know if the callback completed already.
1594  */
1595 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1596 {
1597 	int		value;
1598 
1599 	if (is_root_hub(urb->dev))
1600 		value = usb_rh_urb_dequeue(hcd, urb, status);
1601 	else {
1602 
1603 		/* The only reason an HCD might fail this call is if
1604 		 * it has not yet fully queued the urb to begin with.
1605 		 * Such failures should be harmless. */
1606 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1607 	}
1608 	return value;
1609 }
1610 
1611 /*
1612  * called in any context
1613  *
1614  * caller guarantees urb won't be recycled till both unlink()
1615  * and the urb's completion function return
1616  */
1617 int usb_hcd_unlink_urb (struct urb *urb, int status)
1618 {
1619 	struct usb_hcd		*hcd;
1620 	int			retval = -EIDRM;
1621 	unsigned long		flags;
1622 
1623 	/* Prevent the device and bus from going away while
1624 	 * the unlink is carried out.  If they are already gone
1625 	 * then urb->use_count must be 0, since disconnected
1626 	 * devices can't have any active URBs.
1627 	 */
1628 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1629 	if (atomic_read(&urb->use_count) > 0) {
1630 		retval = 0;
1631 		usb_get_dev(urb->dev);
1632 	}
1633 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1634 	if (retval == 0) {
1635 		hcd = bus_to_hcd(urb->dev->bus);
1636 		retval = unlink1(hcd, urb, status);
1637 		usb_put_dev(urb->dev);
1638 	}
1639 
1640 	if (retval == 0)
1641 		retval = -EINPROGRESS;
1642 	else if (retval != -EIDRM && retval != -EBUSY)
1643 		dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
1644 				urb, retval);
1645 	return retval;
1646 }
1647 
1648 /*-------------------------------------------------------------------------*/
1649 
1650 static void __usb_hcd_giveback_urb(struct urb *urb)
1651 {
1652 	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1653 	struct usb_anchor *anchor = urb->anchor;
1654 	int status = urb->unlinked;
1655 	unsigned long flags;
1656 
1657 	urb->hcpriv = NULL;
1658 	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1659 	    urb->actual_length < urb->transfer_buffer_length &&
1660 	    !status))
1661 		status = -EREMOTEIO;
1662 
1663 	unmap_urb_for_dma(hcd, urb);
1664 	usbmon_urb_complete(&hcd->self, urb, status);
1665 	usb_anchor_suspend_wakeups(anchor);
1666 	usb_unanchor_urb(urb);
1667 
1668 	/* pass ownership to the completion handler */
1669 	urb->status = status;
1670 
1671 	/*
1672 	 * We disable local IRQs here avoid possible deadlock because
1673 	 * drivers may call spin_lock() to hold lock which might be
1674 	 * acquired in one hard interrupt handler.
1675 	 *
1676 	 * The local_irq_save()/local_irq_restore() around complete()
1677 	 * will be removed if current USB drivers have been cleaned up
1678 	 * and no one may trigger the above deadlock situation when
1679 	 * running complete() in tasklet.
1680 	 */
1681 	local_irq_save(flags);
1682 	urb->complete(urb);
1683 	local_irq_restore(flags);
1684 
1685 	usb_anchor_resume_wakeups(anchor);
1686 	atomic_dec(&urb->use_count);
1687 	if (unlikely(atomic_read(&urb->reject)))
1688 		wake_up(&usb_kill_urb_queue);
1689 	usb_put_urb(urb);
1690 }
1691 
1692 static void usb_giveback_urb_bh(unsigned long param)
1693 {
1694 	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1695 	struct list_head local_list;
1696 
1697 	spin_lock_irq(&bh->lock);
1698 	bh->running = true;
1699  restart:
1700 	list_replace_init(&bh->head, &local_list);
1701 	spin_unlock_irq(&bh->lock);
1702 
1703 	while (!list_empty(&local_list)) {
1704 		struct urb *urb;
1705 
1706 		urb = list_entry(local_list.next, struct urb, urb_list);
1707 		list_del_init(&urb->urb_list);
1708 		bh->completing_ep = urb->ep;
1709 		__usb_hcd_giveback_urb(urb);
1710 		bh->completing_ep = NULL;
1711 	}
1712 
1713 	/* check if there are new URBs to giveback */
1714 	spin_lock_irq(&bh->lock);
1715 	if (!list_empty(&bh->head))
1716 		goto restart;
1717 	bh->running = false;
1718 	spin_unlock_irq(&bh->lock);
1719 }
1720 
1721 /**
1722  * usb_hcd_giveback_urb - return URB from HCD to device driver
1723  * @hcd: host controller returning the URB
1724  * @urb: urb being returned to the USB device driver.
1725  * @status: completion status code for the URB.
1726  * Context: in_interrupt()
1727  *
1728  * This hands the URB from HCD to its USB device driver, using its
1729  * completion function.  The HCD has freed all per-urb resources
1730  * (and is done using urb->hcpriv).  It also released all HCD locks;
1731  * the device driver won't cause problems if it frees, modifies,
1732  * or resubmits this URB.
1733  *
1734  * If @urb was unlinked, the value of @status will be overridden by
1735  * @urb->unlinked.  Erroneous short transfers are detected in case
1736  * the HCD hasn't checked for them.
1737  */
1738 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1739 {
1740 	struct giveback_urb_bh *bh;
1741 	bool running, high_prio_bh;
1742 
1743 	/* pass status to tasklet via unlinked */
1744 	if (likely(!urb->unlinked))
1745 		urb->unlinked = status;
1746 
1747 	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1748 		__usb_hcd_giveback_urb(urb);
1749 		return;
1750 	}
1751 
1752 	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1753 		bh = &hcd->high_prio_bh;
1754 		high_prio_bh = true;
1755 	} else {
1756 		bh = &hcd->low_prio_bh;
1757 		high_prio_bh = false;
1758 	}
1759 
1760 	spin_lock(&bh->lock);
1761 	list_add_tail(&urb->urb_list, &bh->head);
1762 	running = bh->running;
1763 	spin_unlock(&bh->lock);
1764 
1765 	if (running)
1766 		;
1767 	else if (high_prio_bh)
1768 		tasklet_hi_schedule(&bh->bh);
1769 	else
1770 		tasklet_schedule(&bh->bh);
1771 }
1772 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1773 
1774 /*-------------------------------------------------------------------------*/
1775 
1776 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1777  * queue to drain completely.  The caller must first insure that no more
1778  * URBs can be submitted for this endpoint.
1779  */
1780 void usb_hcd_flush_endpoint(struct usb_device *udev,
1781 		struct usb_host_endpoint *ep)
1782 {
1783 	struct usb_hcd		*hcd;
1784 	struct urb		*urb;
1785 
1786 	if (!ep)
1787 		return;
1788 	might_sleep();
1789 	hcd = bus_to_hcd(udev->bus);
1790 
1791 	/* No more submits can occur */
1792 	spin_lock_irq(&hcd_urb_list_lock);
1793 rescan:
1794 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1795 		int	is_in;
1796 
1797 		if (urb->unlinked)
1798 			continue;
1799 		usb_get_urb (urb);
1800 		is_in = usb_urb_dir_in(urb);
1801 		spin_unlock(&hcd_urb_list_lock);
1802 
1803 		/* kick hcd */
1804 		unlink1(hcd, urb, -ESHUTDOWN);
1805 		dev_dbg (hcd->self.controller,
1806 			"shutdown urb %p ep%d%s%s\n",
1807 			urb, usb_endpoint_num(&ep->desc),
1808 			is_in ? "in" : "out",
1809 			({	char *s;
1810 
1811 				 switch (usb_endpoint_type(&ep->desc)) {
1812 				 case USB_ENDPOINT_XFER_CONTROL:
1813 					s = ""; break;
1814 				 case USB_ENDPOINT_XFER_BULK:
1815 					s = "-bulk"; break;
1816 				 case USB_ENDPOINT_XFER_INT:
1817 					s = "-intr"; break;
1818 				 default:
1819 					s = "-iso"; break;
1820 				};
1821 				s;
1822 			}));
1823 		usb_put_urb (urb);
1824 
1825 		/* list contents may have changed */
1826 		spin_lock(&hcd_urb_list_lock);
1827 		goto rescan;
1828 	}
1829 	spin_unlock_irq(&hcd_urb_list_lock);
1830 
1831 	/* Wait until the endpoint queue is completely empty */
1832 	while (!list_empty (&ep->urb_list)) {
1833 		spin_lock_irq(&hcd_urb_list_lock);
1834 
1835 		/* The list may have changed while we acquired the spinlock */
1836 		urb = NULL;
1837 		if (!list_empty (&ep->urb_list)) {
1838 			urb = list_entry (ep->urb_list.prev, struct urb,
1839 					urb_list);
1840 			usb_get_urb (urb);
1841 		}
1842 		spin_unlock_irq(&hcd_urb_list_lock);
1843 
1844 		if (urb) {
1845 			usb_kill_urb (urb);
1846 			usb_put_urb (urb);
1847 		}
1848 	}
1849 }
1850 
1851 /**
1852  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1853  *				the bus bandwidth
1854  * @udev: target &usb_device
1855  * @new_config: new configuration to install
1856  * @cur_alt: the current alternate interface setting
1857  * @new_alt: alternate interface setting that is being installed
1858  *
1859  * To change configurations, pass in the new configuration in new_config,
1860  * and pass NULL for cur_alt and new_alt.
1861  *
1862  * To reset a device's configuration (put the device in the ADDRESSED state),
1863  * pass in NULL for new_config, cur_alt, and new_alt.
1864  *
1865  * To change alternate interface settings, pass in NULL for new_config,
1866  * pass in the current alternate interface setting in cur_alt,
1867  * and pass in the new alternate interface setting in new_alt.
1868  *
1869  * Return: An error if the requested bandwidth change exceeds the
1870  * bus bandwidth or host controller internal resources.
1871  */
1872 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1873 		struct usb_host_config *new_config,
1874 		struct usb_host_interface *cur_alt,
1875 		struct usb_host_interface *new_alt)
1876 {
1877 	int num_intfs, i, j;
1878 	struct usb_host_interface *alt = NULL;
1879 	int ret = 0;
1880 	struct usb_hcd *hcd;
1881 	struct usb_host_endpoint *ep;
1882 
1883 	hcd = bus_to_hcd(udev->bus);
1884 	if (!hcd->driver->check_bandwidth)
1885 		return 0;
1886 
1887 	/* Configuration is being removed - set configuration 0 */
1888 	if (!new_config && !cur_alt) {
1889 		for (i = 1; i < 16; ++i) {
1890 			ep = udev->ep_out[i];
1891 			if (ep)
1892 				hcd->driver->drop_endpoint(hcd, udev, ep);
1893 			ep = udev->ep_in[i];
1894 			if (ep)
1895 				hcd->driver->drop_endpoint(hcd, udev, ep);
1896 		}
1897 		hcd->driver->check_bandwidth(hcd, udev);
1898 		return 0;
1899 	}
1900 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1901 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1902 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1903 	 * ok to exclude it.
1904 	 */
1905 	if (new_config) {
1906 		num_intfs = new_config->desc.bNumInterfaces;
1907 		/* Remove endpoints (except endpoint 0, which is always on the
1908 		 * schedule) from the old config from the schedule
1909 		 */
1910 		for (i = 1; i < 16; ++i) {
1911 			ep = udev->ep_out[i];
1912 			if (ep) {
1913 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1914 				if (ret < 0)
1915 					goto reset;
1916 			}
1917 			ep = udev->ep_in[i];
1918 			if (ep) {
1919 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1920 				if (ret < 0)
1921 					goto reset;
1922 			}
1923 		}
1924 		for (i = 0; i < num_intfs; ++i) {
1925 			struct usb_host_interface *first_alt;
1926 			int iface_num;
1927 
1928 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1929 			iface_num = first_alt->desc.bInterfaceNumber;
1930 			/* Set up endpoints for alternate interface setting 0 */
1931 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1932 			if (!alt)
1933 				/* No alt setting 0? Pick the first setting. */
1934 				alt = first_alt;
1935 
1936 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1937 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1938 				if (ret < 0)
1939 					goto reset;
1940 			}
1941 		}
1942 	}
1943 	if (cur_alt && new_alt) {
1944 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1945 				cur_alt->desc.bInterfaceNumber);
1946 
1947 		if (!iface)
1948 			return -EINVAL;
1949 		if (iface->resetting_device) {
1950 			/*
1951 			 * The USB core just reset the device, so the xHCI host
1952 			 * and the device will think alt setting 0 is installed.
1953 			 * However, the USB core will pass in the alternate
1954 			 * setting installed before the reset as cur_alt.  Dig
1955 			 * out the alternate setting 0 structure, or the first
1956 			 * alternate setting if a broken device doesn't have alt
1957 			 * setting 0.
1958 			 */
1959 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1960 			if (!cur_alt)
1961 				cur_alt = &iface->altsetting[0];
1962 		}
1963 
1964 		/* Drop all the endpoints in the current alt setting */
1965 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1966 			ret = hcd->driver->drop_endpoint(hcd, udev,
1967 					&cur_alt->endpoint[i]);
1968 			if (ret < 0)
1969 				goto reset;
1970 		}
1971 		/* Add all the endpoints in the new alt setting */
1972 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1973 			ret = hcd->driver->add_endpoint(hcd, udev,
1974 					&new_alt->endpoint[i]);
1975 			if (ret < 0)
1976 				goto reset;
1977 		}
1978 	}
1979 	ret = hcd->driver->check_bandwidth(hcd, udev);
1980 reset:
1981 	if (ret < 0)
1982 		hcd->driver->reset_bandwidth(hcd, udev);
1983 	return ret;
1984 }
1985 
1986 /* Disables the endpoint: synchronizes with the hcd to make sure all
1987  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1988  * have been called previously.  Use for set_configuration, set_interface,
1989  * driver removal, physical disconnect.
1990  *
1991  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1992  * type, maxpacket size, toggle, halt status, and scheduling.
1993  */
1994 void usb_hcd_disable_endpoint(struct usb_device *udev,
1995 		struct usb_host_endpoint *ep)
1996 {
1997 	struct usb_hcd		*hcd;
1998 
1999 	might_sleep();
2000 	hcd = bus_to_hcd(udev->bus);
2001 	if (hcd->driver->endpoint_disable)
2002 		hcd->driver->endpoint_disable(hcd, ep);
2003 }
2004 
2005 /**
2006  * usb_hcd_reset_endpoint - reset host endpoint state
2007  * @udev: USB device.
2008  * @ep:   the endpoint to reset.
2009  *
2010  * Resets any host endpoint state such as the toggle bit, sequence
2011  * number and current window.
2012  */
2013 void usb_hcd_reset_endpoint(struct usb_device *udev,
2014 			    struct usb_host_endpoint *ep)
2015 {
2016 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2017 
2018 	if (hcd->driver->endpoint_reset)
2019 		hcd->driver->endpoint_reset(hcd, ep);
2020 	else {
2021 		int epnum = usb_endpoint_num(&ep->desc);
2022 		int is_out = usb_endpoint_dir_out(&ep->desc);
2023 		int is_control = usb_endpoint_xfer_control(&ep->desc);
2024 
2025 		usb_settoggle(udev, epnum, is_out, 0);
2026 		if (is_control)
2027 			usb_settoggle(udev, epnum, !is_out, 0);
2028 	}
2029 }
2030 
2031 /**
2032  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2033  * @interface:		alternate setting that includes all endpoints.
2034  * @eps:		array of endpoints that need streams.
2035  * @num_eps:		number of endpoints in the array.
2036  * @num_streams:	number of streams to allocate.
2037  * @mem_flags:		flags hcd should use to allocate memory.
2038  *
2039  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2040  * Drivers may queue multiple transfers to different stream IDs, which may
2041  * complete in a different order than they were queued.
2042  *
2043  * Return: On success, the number of allocated streams. On failure, a negative
2044  * error code.
2045  */
2046 int usb_alloc_streams(struct usb_interface *interface,
2047 		struct usb_host_endpoint **eps, unsigned int num_eps,
2048 		unsigned int num_streams, gfp_t mem_flags)
2049 {
2050 	struct usb_hcd *hcd;
2051 	struct usb_device *dev;
2052 	int i, ret;
2053 
2054 	dev = interface_to_usbdev(interface);
2055 	hcd = bus_to_hcd(dev->bus);
2056 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2057 		return -EINVAL;
2058 	if (dev->speed != USB_SPEED_SUPER)
2059 		return -EINVAL;
2060 
2061 	for (i = 0; i < num_eps; i++) {
2062 		/* Streams only apply to bulk endpoints. */
2063 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2064 			return -EINVAL;
2065 		/* Re-alloc is not allowed */
2066 		if (eps[i]->streams)
2067 			return -EINVAL;
2068 	}
2069 
2070 	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2071 			num_streams, mem_flags);
2072 	if (ret < 0)
2073 		return ret;
2074 
2075 	for (i = 0; i < num_eps; i++)
2076 		eps[i]->streams = ret;
2077 
2078 	return ret;
2079 }
2080 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2081 
2082 /**
2083  * usb_free_streams - free bulk endpoint stream IDs.
2084  * @interface:	alternate setting that includes all endpoints.
2085  * @eps:	array of endpoints to remove streams from.
2086  * @num_eps:	number of endpoints in the array.
2087  * @mem_flags:	flags hcd should use to allocate memory.
2088  *
2089  * Reverts a group of bulk endpoints back to not using stream IDs.
2090  * Can fail if we are given bad arguments, or HCD is broken.
2091  *
2092  * Return: 0 on success. On failure, a negative error code.
2093  */
2094 int usb_free_streams(struct usb_interface *interface,
2095 		struct usb_host_endpoint **eps, unsigned int num_eps,
2096 		gfp_t mem_flags)
2097 {
2098 	struct usb_hcd *hcd;
2099 	struct usb_device *dev;
2100 	int i, ret;
2101 
2102 	dev = interface_to_usbdev(interface);
2103 	hcd = bus_to_hcd(dev->bus);
2104 	if (dev->speed != USB_SPEED_SUPER)
2105 		return -EINVAL;
2106 
2107 	/* Double-free is not allowed */
2108 	for (i = 0; i < num_eps; i++)
2109 		if (!eps[i] || !eps[i]->streams)
2110 			return -EINVAL;
2111 
2112 	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2113 	if (ret < 0)
2114 		return ret;
2115 
2116 	for (i = 0; i < num_eps; i++)
2117 		eps[i]->streams = 0;
2118 
2119 	return ret;
2120 }
2121 EXPORT_SYMBOL_GPL(usb_free_streams);
2122 
2123 /* Protect against drivers that try to unlink URBs after the device
2124  * is gone, by waiting until all unlinks for @udev are finished.
2125  * Since we don't currently track URBs by device, simply wait until
2126  * nothing is running in the locked region of usb_hcd_unlink_urb().
2127  */
2128 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2129 {
2130 	spin_lock_irq(&hcd_urb_unlink_lock);
2131 	spin_unlock_irq(&hcd_urb_unlink_lock);
2132 }
2133 
2134 /*-------------------------------------------------------------------------*/
2135 
2136 /* called in any context */
2137 int usb_hcd_get_frame_number (struct usb_device *udev)
2138 {
2139 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2140 
2141 	if (!HCD_RH_RUNNING(hcd))
2142 		return -ESHUTDOWN;
2143 	return hcd->driver->get_frame_number (hcd);
2144 }
2145 
2146 /*-------------------------------------------------------------------------*/
2147 
2148 #ifdef	CONFIG_PM
2149 
2150 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2151 {
2152 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2153 	int		status;
2154 	int		old_state = hcd->state;
2155 
2156 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2157 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2158 			rhdev->do_remote_wakeup);
2159 	if (HCD_DEAD(hcd)) {
2160 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2161 		return 0;
2162 	}
2163 
2164 	if (!hcd->driver->bus_suspend) {
2165 		status = -ENOENT;
2166 	} else {
2167 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2168 		hcd->state = HC_STATE_QUIESCING;
2169 		status = hcd->driver->bus_suspend(hcd);
2170 	}
2171 	if (status == 0) {
2172 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2173 		hcd->state = HC_STATE_SUSPENDED;
2174 
2175 		/* Did we race with a root-hub wakeup event? */
2176 		if (rhdev->do_remote_wakeup) {
2177 			char	buffer[6];
2178 
2179 			status = hcd->driver->hub_status_data(hcd, buffer);
2180 			if (status != 0) {
2181 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2182 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2183 				status = -EBUSY;
2184 			}
2185 		}
2186 	} else {
2187 		spin_lock_irq(&hcd_root_hub_lock);
2188 		if (!HCD_DEAD(hcd)) {
2189 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2190 			hcd->state = old_state;
2191 		}
2192 		spin_unlock_irq(&hcd_root_hub_lock);
2193 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2194 				"suspend", status);
2195 	}
2196 	return status;
2197 }
2198 
2199 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2200 {
2201 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2202 	int		status;
2203 	int		old_state = hcd->state;
2204 
2205 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2206 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2207 	if (HCD_DEAD(hcd)) {
2208 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2209 		return 0;
2210 	}
2211 	if (!hcd->driver->bus_resume)
2212 		return -ENOENT;
2213 	if (HCD_RH_RUNNING(hcd))
2214 		return 0;
2215 
2216 	hcd->state = HC_STATE_RESUMING;
2217 	status = hcd->driver->bus_resume(hcd);
2218 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2219 	if (status == 0) {
2220 		struct usb_device *udev;
2221 		int port1;
2222 
2223 		spin_lock_irq(&hcd_root_hub_lock);
2224 		if (!HCD_DEAD(hcd)) {
2225 			usb_set_device_state(rhdev, rhdev->actconfig
2226 					? USB_STATE_CONFIGURED
2227 					: USB_STATE_ADDRESS);
2228 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2229 			hcd->state = HC_STATE_RUNNING;
2230 		}
2231 		spin_unlock_irq(&hcd_root_hub_lock);
2232 
2233 		/*
2234 		 * Check whether any of the enabled ports on the root hub are
2235 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2236 		 * (this is what the USB-2 spec calls a "global resume").
2237 		 * Otherwise we can skip the delay.
2238 		 */
2239 		usb_hub_for_each_child(rhdev, port1, udev) {
2240 			if (udev->state != USB_STATE_NOTATTACHED &&
2241 					!udev->port_is_suspended) {
2242 				usleep_range(10000, 11000);	/* TRSMRCY */
2243 				break;
2244 			}
2245 		}
2246 	} else {
2247 		hcd->state = old_state;
2248 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2249 				"resume", status);
2250 		if (status != -ESHUTDOWN)
2251 			usb_hc_died(hcd);
2252 	}
2253 	return status;
2254 }
2255 
2256 #endif	/* CONFIG_PM */
2257 
2258 #ifdef	CONFIG_PM_RUNTIME
2259 
2260 /* Workqueue routine for root-hub remote wakeup */
2261 static void hcd_resume_work(struct work_struct *work)
2262 {
2263 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2264 	struct usb_device *udev = hcd->self.root_hub;
2265 
2266 	usb_remote_wakeup(udev);
2267 }
2268 
2269 /**
2270  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2271  * @hcd: host controller for this root hub
2272  *
2273  * The USB host controller calls this function when its root hub is
2274  * suspended (with the remote wakeup feature enabled) and a remote
2275  * wakeup request is received.  The routine submits a workqueue request
2276  * to resume the root hub (that is, manage its downstream ports again).
2277  */
2278 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2279 {
2280 	unsigned long flags;
2281 
2282 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2283 	if (hcd->rh_registered) {
2284 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2285 		queue_work(pm_wq, &hcd->wakeup_work);
2286 	}
2287 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2288 }
2289 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2290 
2291 #endif	/* CONFIG_PM_RUNTIME */
2292 
2293 /*-------------------------------------------------------------------------*/
2294 
2295 #ifdef	CONFIG_USB_OTG
2296 
2297 /**
2298  * usb_bus_start_enum - start immediate enumeration (for OTG)
2299  * @bus: the bus (must use hcd framework)
2300  * @port_num: 1-based number of port; usually bus->otg_port
2301  * Context: in_interrupt()
2302  *
2303  * Starts enumeration, with an immediate reset followed later by
2304  * khubd identifying and possibly configuring the device.
2305  * This is needed by OTG controller drivers, where it helps meet
2306  * HNP protocol timing requirements for starting a port reset.
2307  *
2308  * Return: 0 if successful.
2309  */
2310 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2311 {
2312 	struct usb_hcd		*hcd;
2313 	int			status = -EOPNOTSUPP;
2314 
2315 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2316 	 * boards with root hubs hooked up to internal devices (instead of
2317 	 * just the OTG port) may need more attention to resetting...
2318 	 */
2319 	hcd = container_of (bus, struct usb_hcd, self);
2320 	if (port_num && hcd->driver->start_port_reset)
2321 		status = hcd->driver->start_port_reset(hcd, port_num);
2322 
2323 	/* run khubd shortly after (first) root port reset finishes;
2324 	 * it may issue others, until at least 50 msecs have passed.
2325 	 */
2326 	if (status == 0)
2327 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2328 	return status;
2329 }
2330 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2331 
2332 #endif
2333 
2334 /*-------------------------------------------------------------------------*/
2335 
2336 /**
2337  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2338  * @irq: the IRQ being raised
2339  * @__hcd: pointer to the HCD whose IRQ is being signaled
2340  *
2341  * If the controller isn't HALTed, calls the driver's irq handler.
2342  * Checks whether the controller is now dead.
2343  *
2344  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2345  */
2346 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2347 {
2348 	struct usb_hcd		*hcd = __hcd;
2349 	irqreturn_t		rc;
2350 
2351 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2352 		rc = IRQ_NONE;
2353 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2354 		rc = IRQ_NONE;
2355 	else
2356 		rc = IRQ_HANDLED;
2357 
2358 	return rc;
2359 }
2360 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2361 
2362 /*-------------------------------------------------------------------------*/
2363 
2364 /**
2365  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2366  * @hcd: pointer to the HCD representing the controller
2367  *
2368  * This is called by bus glue to report a USB host controller that died
2369  * while operations may still have been pending.  It's called automatically
2370  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2371  *
2372  * Only call this function with the primary HCD.
2373  */
2374 void usb_hc_died (struct usb_hcd *hcd)
2375 {
2376 	unsigned long flags;
2377 
2378 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2379 
2380 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2381 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2382 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2383 	if (hcd->rh_registered) {
2384 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2385 
2386 		/* make khubd clean up old urbs and devices */
2387 		usb_set_device_state (hcd->self.root_hub,
2388 				USB_STATE_NOTATTACHED);
2389 		usb_kick_khubd (hcd->self.root_hub);
2390 	}
2391 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2392 		hcd = hcd->shared_hcd;
2393 		if (hcd->rh_registered) {
2394 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2395 
2396 			/* make khubd clean up old urbs and devices */
2397 			usb_set_device_state(hcd->self.root_hub,
2398 					USB_STATE_NOTATTACHED);
2399 			usb_kick_khubd(hcd->self.root_hub);
2400 		}
2401 	}
2402 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2403 	/* Make sure that the other roothub is also deallocated. */
2404 }
2405 EXPORT_SYMBOL_GPL (usb_hc_died);
2406 
2407 /*-------------------------------------------------------------------------*/
2408 
2409 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2410 {
2411 
2412 	spin_lock_init(&bh->lock);
2413 	INIT_LIST_HEAD(&bh->head);
2414 	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2415 }
2416 
2417 /**
2418  * usb_create_shared_hcd - create and initialize an HCD structure
2419  * @driver: HC driver that will use this hcd
2420  * @dev: device for this HC, stored in hcd->self.controller
2421  * @bus_name: value to store in hcd->self.bus_name
2422  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2423  *              PCI device.  Only allocate certain resources for the primary HCD
2424  * Context: !in_interrupt()
2425  *
2426  * Allocate a struct usb_hcd, with extra space at the end for the
2427  * HC driver's private data.  Initialize the generic members of the
2428  * hcd structure.
2429  *
2430  * Return: On success, a pointer to the created and initialized HCD structure.
2431  * On failure (e.g. if memory is unavailable), %NULL.
2432  */
2433 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2434 		struct device *dev, const char *bus_name,
2435 		struct usb_hcd *primary_hcd)
2436 {
2437 	struct usb_hcd *hcd;
2438 
2439 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2440 	if (!hcd) {
2441 		dev_dbg (dev, "hcd alloc failed\n");
2442 		return NULL;
2443 	}
2444 	if (primary_hcd == NULL) {
2445 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2446 				GFP_KERNEL);
2447 		if (!hcd->bandwidth_mutex) {
2448 			kfree(hcd);
2449 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2450 			return NULL;
2451 		}
2452 		mutex_init(hcd->bandwidth_mutex);
2453 		dev_set_drvdata(dev, hcd);
2454 	} else {
2455 		mutex_lock(&usb_port_peer_mutex);
2456 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2457 		hcd->primary_hcd = primary_hcd;
2458 		primary_hcd->primary_hcd = primary_hcd;
2459 		hcd->shared_hcd = primary_hcd;
2460 		primary_hcd->shared_hcd = hcd;
2461 		mutex_unlock(&usb_port_peer_mutex);
2462 	}
2463 
2464 	kref_init(&hcd->kref);
2465 
2466 	usb_bus_init(&hcd->self);
2467 	hcd->self.controller = dev;
2468 	hcd->self.bus_name = bus_name;
2469 	hcd->self.uses_dma = (dev->dma_mask != NULL);
2470 
2471 	init_timer(&hcd->rh_timer);
2472 	hcd->rh_timer.function = rh_timer_func;
2473 	hcd->rh_timer.data = (unsigned long) hcd;
2474 #ifdef CONFIG_PM_RUNTIME
2475 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2476 #endif
2477 
2478 	hcd->driver = driver;
2479 	hcd->speed = driver->flags & HCD_MASK;
2480 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2481 			"USB Host Controller";
2482 	return hcd;
2483 }
2484 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2485 
2486 /**
2487  * usb_create_hcd - create and initialize an HCD structure
2488  * @driver: HC driver that will use this hcd
2489  * @dev: device for this HC, stored in hcd->self.controller
2490  * @bus_name: value to store in hcd->self.bus_name
2491  * Context: !in_interrupt()
2492  *
2493  * Allocate a struct usb_hcd, with extra space at the end for the
2494  * HC driver's private data.  Initialize the generic members of the
2495  * hcd structure.
2496  *
2497  * Return: On success, a pointer to the created and initialized HCD
2498  * structure. On failure (e.g. if memory is unavailable), %NULL.
2499  */
2500 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2501 		struct device *dev, const char *bus_name)
2502 {
2503 	return usb_create_shared_hcd(driver, dev, bus_name, NULL);
2504 }
2505 EXPORT_SYMBOL_GPL(usb_create_hcd);
2506 
2507 /*
2508  * Roothubs that share one PCI device must also share the bandwidth mutex.
2509  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2510  * deallocated.
2511  *
2512  * Make sure to only deallocate the bandwidth_mutex when the primary HCD is
2513  * freed.  When hcd_release() is called for either hcd in a peer set
2514  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers to
2515  * block new peering attempts
2516  */
2517 static void hcd_release(struct kref *kref)
2518 {
2519 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2520 
2521 	mutex_lock(&usb_port_peer_mutex);
2522 	if (usb_hcd_is_primary_hcd(hcd))
2523 		kfree(hcd->bandwidth_mutex);
2524 	if (hcd->shared_hcd) {
2525 		struct usb_hcd *peer = hcd->shared_hcd;
2526 
2527 		peer->shared_hcd = NULL;
2528 		if (peer->primary_hcd == hcd)
2529 			peer->primary_hcd = NULL;
2530 	}
2531 	mutex_unlock(&usb_port_peer_mutex);
2532 	kfree(hcd);
2533 }
2534 
2535 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2536 {
2537 	if (hcd)
2538 		kref_get (&hcd->kref);
2539 	return hcd;
2540 }
2541 EXPORT_SYMBOL_GPL(usb_get_hcd);
2542 
2543 void usb_put_hcd (struct usb_hcd *hcd)
2544 {
2545 	if (hcd)
2546 		kref_put (&hcd->kref, hcd_release);
2547 }
2548 EXPORT_SYMBOL_GPL(usb_put_hcd);
2549 
2550 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2551 {
2552 	if (!hcd->primary_hcd)
2553 		return 1;
2554 	return hcd == hcd->primary_hcd;
2555 }
2556 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2557 
2558 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2559 {
2560 	if (!hcd->driver->find_raw_port_number)
2561 		return port1;
2562 
2563 	return hcd->driver->find_raw_port_number(hcd, port1);
2564 }
2565 
2566 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2567 		unsigned int irqnum, unsigned long irqflags)
2568 {
2569 	int retval;
2570 
2571 	if (hcd->driver->irq) {
2572 
2573 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2574 				hcd->driver->description, hcd->self.busnum);
2575 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2576 				hcd->irq_descr, hcd);
2577 		if (retval != 0) {
2578 			dev_err(hcd->self.controller,
2579 					"request interrupt %d failed\n",
2580 					irqnum);
2581 			return retval;
2582 		}
2583 		hcd->irq = irqnum;
2584 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2585 				(hcd->driver->flags & HCD_MEMORY) ?
2586 					"io mem" : "io base",
2587 					(unsigned long long)hcd->rsrc_start);
2588 	} else {
2589 		hcd->irq = 0;
2590 		if (hcd->rsrc_start)
2591 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2592 					(hcd->driver->flags & HCD_MEMORY) ?
2593 					"io mem" : "io base",
2594 					(unsigned long long)hcd->rsrc_start);
2595 	}
2596 	return 0;
2597 }
2598 
2599 /*
2600  * Before we free this root hub, flush in-flight peering attempts
2601  * and disable peer lookups
2602  */
2603 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2604 {
2605 	struct usb_device *rhdev;
2606 
2607 	mutex_lock(&usb_port_peer_mutex);
2608 	rhdev = hcd->self.root_hub;
2609 	hcd->self.root_hub = NULL;
2610 	mutex_unlock(&usb_port_peer_mutex);
2611 	usb_put_dev(rhdev);
2612 }
2613 
2614 /**
2615  * usb_add_hcd - finish generic HCD structure initialization and register
2616  * @hcd: the usb_hcd structure to initialize
2617  * @irqnum: Interrupt line to allocate
2618  * @irqflags: Interrupt type flags
2619  *
2620  * Finish the remaining parts of generic HCD initialization: allocate the
2621  * buffers of consistent memory, register the bus, request the IRQ line,
2622  * and call the driver's reset() and start() routines.
2623  */
2624 int usb_add_hcd(struct usb_hcd *hcd,
2625 		unsigned int irqnum, unsigned long irqflags)
2626 {
2627 	int retval;
2628 	struct usb_device *rhdev;
2629 
2630 	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->phy) {
2631 		struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
2632 
2633 		if (IS_ERR(phy)) {
2634 			retval = PTR_ERR(phy);
2635 			if (retval == -EPROBE_DEFER)
2636 				return retval;
2637 		} else {
2638 			retval = usb_phy_init(phy);
2639 			if (retval) {
2640 				usb_put_phy(phy);
2641 				return retval;
2642 			}
2643 			hcd->phy = phy;
2644 			hcd->remove_phy = 1;
2645 		}
2646 	}
2647 
2648 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2649 
2650 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2651 	if (authorized_default < 0 || authorized_default > 1)
2652 		hcd->authorized_default = hcd->wireless ? 0 : 1;
2653 	else
2654 		hcd->authorized_default = authorized_default;
2655 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2656 
2657 	/* HC is in reset state, but accessible.  Now do the one-time init,
2658 	 * bottom up so that hcds can customize the root hubs before khubd
2659 	 * starts talking to them.  (Note, bus id is assigned early too.)
2660 	 */
2661 	if ((retval = hcd_buffer_create(hcd)) != 0) {
2662 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
2663 		goto err_remove_phy;
2664 	}
2665 
2666 	if ((retval = usb_register_bus(&hcd->self)) < 0)
2667 		goto err_register_bus;
2668 
2669 	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
2670 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
2671 		retval = -ENOMEM;
2672 		goto err_allocate_root_hub;
2673 	}
2674 	mutex_lock(&usb_port_peer_mutex);
2675 	hcd->self.root_hub = rhdev;
2676 	mutex_unlock(&usb_port_peer_mutex);
2677 
2678 	switch (hcd->speed) {
2679 	case HCD_USB11:
2680 		rhdev->speed = USB_SPEED_FULL;
2681 		break;
2682 	case HCD_USB2:
2683 		rhdev->speed = USB_SPEED_HIGH;
2684 		break;
2685 	case HCD_USB25:
2686 		rhdev->speed = USB_SPEED_WIRELESS;
2687 		break;
2688 	case HCD_USB3:
2689 		rhdev->speed = USB_SPEED_SUPER;
2690 		break;
2691 	default:
2692 		retval = -EINVAL;
2693 		goto err_set_rh_speed;
2694 	}
2695 
2696 	/* wakeup flag init defaults to "everything works" for root hubs,
2697 	 * but drivers can override it in reset() if needed, along with
2698 	 * recording the overall controller's system wakeup capability.
2699 	 */
2700 	device_set_wakeup_capable(&rhdev->dev, 1);
2701 
2702 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2703 	 * registered.  But since the controller can die at any time,
2704 	 * let's initialize the flag before touching the hardware.
2705 	 */
2706 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2707 
2708 	/* "reset" is misnamed; its role is now one-time init. the controller
2709 	 * should already have been reset (and boot firmware kicked off etc).
2710 	 */
2711 	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
2712 		dev_err(hcd->self.controller, "can't setup: %d\n", retval);
2713 		goto err_hcd_driver_setup;
2714 	}
2715 	hcd->rh_pollable = 1;
2716 
2717 	/* NOTE: root hub and controller capabilities may not be the same */
2718 	if (device_can_wakeup(hcd->self.controller)
2719 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2720 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2721 
2722 	/* initialize tasklets */
2723 	init_giveback_urb_bh(&hcd->high_prio_bh);
2724 	init_giveback_urb_bh(&hcd->low_prio_bh);
2725 
2726 	/* enable irqs just before we start the controller,
2727 	 * if the BIOS provides legacy PCI irqs.
2728 	 */
2729 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2730 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2731 		if (retval)
2732 			goto err_request_irq;
2733 	}
2734 
2735 	hcd->state = HC_STATE_RUNNING;
2736 	retval = hcd->driver->start(hcd);
2737 	if (retval < 0) {
2738 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2739 		goto err_hcd_driver_start;
2740 	}
2741 
2742 	/* starting here, usbcore will pay attention to this root hub */
2743 	if ((retval = register_root_hub(hcd)) != 0)
2744 		goto err_register_root_hub;
2745 
2746 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2747 	if (retval < 0) {
2748 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2749 		       retval);
2750 		goto error_create_attr_group;
2751 	}
2752 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2753 		usb_hcd_poll_rh_status(hcd);
2754 
2755 	return retval;
2756 
2757 error_create_attr_group:
2758 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2759 	if (HC_IS_RUNNING(hcd->state))
2760 		hcd->state = HC_STATE_QUIESCING;
2761 	spin_lock_irq(&hcd_root_hub_lock);
2762 	hcd->rh_registered = 0;
2763 	spin_unlock_irq(&hcd_root_hub_lock);
2764 
2765 #ifdef CONFIG_PM_RUNTIME
2766 	cancel_work_sync(&hcd->wakeup_work);
2767 #endif
2768 	mutex_lock(&usb_bus_list_lock);
2769 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2770 	mutex_unlock(&usb_bus_list_lock);
2771 err_register_root_hub:
2772 	hcd->rh_pollable = 0;
2773 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2774 	del_timer_sync(&hcd->rh_timer);
2775 	hcd->driver->stop(hcd);
2776 	hcd->state = HC_STATE_HALT;
2777 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2778 	del_timer_sync(&hcd->rh_timer);
2779 err_hcd_driver_start:
2780 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2781 		free_irq(irqnum, hcd);
2782 err_request_irq:
2783 err_hcd_driver_setup:
2784 err_set_rh_speed:
2785 	usb_put_invalidate_rhdev(hcd);
2786 err_allocate_root_hub:
2787 	usb_deregister_bus(&hcd->self);
2788 err_register_bus:
2789 	hcd_buffer_destroy(hcd);
2790 err_remove_phy:
2791 	if (hcd->remove_phy && hcd->phy) {
2792 		usb_phy_shutdown(hcd->phy);
2793 		usb_put_phy(hcd->phy);
2794 		hcd->phy = NULL;
2795 	}
2796 	return retval;
2797 }
2798 EXPORT_SYMBOL_GPL(usb_add_hcd);
2799 
2800 /**
2801  * usb_remove_hcd - shutdown processing for generic HCDs
2802  * @hcd: the usb_hcd structure to remove
2803  * Context: !in_interrupt()
2804  *
2805  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2806  * invoking the HCD's stop() method.
2807  */
2808 void usb_remove_hcd(struct usb_hcd *hcd)
2809 {
2810 	struct usb_device *rhdev = hcd->self.root_hub;
2811 
2812 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2813 
2814 	usb_get_dev(rhdev);
2815 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2816 
2817 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2818 	if (HC_IS_RUNNING (hcd->state))
2819 		hcd->state = HC_STATE_QUIESCING;
2820 
2821 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2822 	spin_lock_irq (&hcd_root_hub_lock);
2823 	hcd->rh_registered = 0;
2824 	spin_unlock_irq (&hcd_root_hub_lock);
2825 
2826 #ifdef CONFIG_PM_RUNTIME
2827 	cancel_work_sync(&hcd->wakeup_work);
2828 #endif
2829 
2830 	mutex_lock(&usb_bus_list_lock);
2831 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2832 	mutex_unlock(&usb_bus_list_lock);
2833 
2834 	/*
2835 	 * tasklet_kill() isn't needed here because:
2836 	 * - driver's disconnect() called from usb_disconnect() should
2837 	 *   make sure its URBs are completed during the disconnect()
2838 	 *   callback
2839 	 *
2840 	 * - it is too late to run complete() here since driver may have
2841 	 *   been removed already now
2842 	 */
2843 
2844 	/* Prevent any more root-hub status calls from the timer.
2845 	 * The HCD might still restart the timer (if a port status change
2846 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2847 	 * the hub_status_data() callback.
2848 	 */
2849 	hcd->rh_pollable = 0;
2850 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2851 	del_timer_sync(&hcd->rh_timer);
2852 
2853 	hcd->driver->stop(hcd);
2854 	hcd->state = HC_STATE_HALT;
2855 
2856 	/* In case the HCD restarted the timer, stop it again. */
2857 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2858 	del_timer_sync(&hcd->rh_timer);
2859 
2860 	if (usb_hcd_is_primary_hcd(hcd)) {
2861 		if (hcd->irq > 0)
2862 			free_irq(hcd->irq, hcd);
2863 	}
2864 
2865 	usb_deregister_bus(&hcd->self);
2866 	hcd_buffer_destroy(hcd);
2867 	if (hcd->remove_phy && hcd->phy) {
2868 		usb_phy_shutdown(hcd->phy);
2869 		usb_put_phy(hcd->phy);
2870 		hcd->phy = NULL;
2871 	}
2872 
2873 	usb_put_invalidate_rhdev(hcd);
2874 }
2875 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2876 
2877 void
2878 usb_hcd_platform_shutdown(struct platform_device *dev)
2879 {
2880 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2881 
2882 	if (hcd->driver->shutdown)
2883 		hcd->driver->shutdown(hcd);
2884 }
2885 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2886 
2887 /*-------------------------------------------------------------------------*/
2888 
2889 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2890 
2891 struct usb_mon_operations *mon_ops;
2892 
2893 /*
2894  * The registration is unlocked.
2895  * We do it this way because we do not want to lock in hot paths.
2896  *
2897  * Notice that the code is minimally error-proof. Because usbmon needs
2898  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2899  */
2900 
2901 int usb_mon_register (struct usb_mon_operations *ops)
2902 {
2903 
2904 	if (mon_ops)
2905 		return -EBUSY;
2906 
2907 	mon_ops = ops;
2908 	mb();
2909 	return 0;
2910 }
2911 EXPORT_SYMBOL_GPL (usb_mon_register);
2912 
2913 void usb_mon_deregister (void)
2914 {
2915 
2916 	if (mon_ops == NULL) {
2917 		printk(KERN_ERR "USB: monitor was not registered\n");
2918 		return;
2919 	}
2920 	mon_ops = NULL;
2921 	mb();
2922 }
2923 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2924 
2925 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2926