xref: /linux/drivers/usb/core/hcd.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
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 
43 #include <linux/usb.h>
44 #include <linux/usb/hcd.h>
45 
46 #include "usb.h"
47 
48 
49 /*-------------------------------------------------------------------------*/
50 
51 /*
52  * USB Host Controller Driver framework
53  *
54  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
55  * HCD-specific behaviors/bugs.
56  *
57  * This does error checks, tracks devices and urbs, and delegates to a
58  * "hc_driver" only for code (and data) that really needs to know about
59  * hardware differences.  That includes root hub registers, i/o queues,
60  * and so on ... but as little else as possible.
61  *
62  * Shared code includes most of the "root hub" code (these are emulated,
63  * though each HC's hardware works differently) and PCI glue, plus request
64  * tracking overhead.  The HCD code should only block on spinlocks or on
65  * hardware handshaking; blocking on software events (such as other kernel
66  * threads releasing resources, or completing actions) is all generic.
67  *
68  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
69  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
70  * only by the hub driver ... and that neither should be seen or used by
71  * usb client device drivers.
72  *
73  * Contributors of ideas or unattributed patches include: David Brownell,
74  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
75  *
76  * HISTORY:
77  * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
78  *		associated cleanup.  "usb_hcd" still != "usb_bus".
79  * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
80  */
81 
82 /*-------------------------------------------------------------------------*/
83 
84 /* Keep track of which host controller drivers are loaded */
85 unsigned long usb_hcds_loaded;
86 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
87 
88 /* host controllers we manage */
89 LIST_HEAD (usb_bus_list);
90 EXPORT_SYMBOL_GPL (usb_bus_list);
91 
92 /* used when allocating bus numbers */
93 #define USB_MAXBUS		64
94 struct usb_busmap {
95 	unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
96 };
97 static struct usb_busmap busmap;
98 
99 /* used when updating list of hcds */
100 DEFINE_MUTEX(usb_bus_list_lock);	/* exported only for usbfs */
101 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
102 
103 /* used for controlling access to virtual root hubs */
104 static DEFINE_SPINLOCK(hcd_root_hub_lock);
105 
106 /* used when updating an endpoint's URB list */
107 static DEFINE_SPINLOCK(hcd_urb_list_lock);
108 
109 /* used to protect against unlinking URBs after the device is gone */
110 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
111 
112 /* wait queue for synchronous unlinks */
113 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
114 
115 static inline int is_root_hub(struct usb_device *udev)
116 {
117 	return (udev->parent == NULL);
118 }
119 
120 /*-------------------------------------------------------------------------*/
121 
122 /*
123  * Sharable chunks of root hub code.
124  */
125 
126 /*-------------------------------------------------------------------------*/
127 #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 2.0 root hub device descriptor */
152 static const u8 usb2_rh_dev_descriptor [18] = {
153 	0x12,       /*  __u8  bLength; */
154 	0x01,       /*  __u8  bDescriptorType; Device */
155 	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
156 
157 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
158 	0x00,	    /*  __u8  bDeviceSubClass; */
159 	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
160 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
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 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
173 
174 /* usb 1.1 root hub device descriptor */
175 static const u8 usb11_rh_dev_descriptor [18] = {
176 	0x12,       /*  __u8  bLength; */
177 	0x01,       /*  __u8  bDescriptorType; Device */
178 	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
179 
180 	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
181 	0x00,	    /*  __u8  bDeviceSubClass; */
182 	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
183 	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
184 
185 	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
186 	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
187 	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
188 
189 	0x03,       /*  __u8  iManufacturer; */
190 	0x02,       /*  __u8  iProduct; */
191 	0x01,       /*  __u8  iSerialNumber; */
192 	0x01        /*  __u8  bNumConfigurations; */
193 };
194 
195 
196 /*-------------------------------------------------------------------------*/
197 
198 /* Configuration descriptors for our root hubs */
199 
200 static const u8 fs_rh_config_descriptor [] = {
201 
202 	/* one configuration */
203 	0x09,       /*  __u8  bLength; */
204 	0x02,       /*  __u8  bDescriptorType; Configuration */
205 	0x19, 0x00, /*  __le16 wTotalLength; */
206 	0x01,       /*  __u8  bNumInterfaces; (1) */
207 	0x01,       /*  __u8  bConfigurationValue; */
208 	0x00,       /*  __u8  iConfiguration; */
209 	0xc0,       /*  __u8  bmAttributes;
210 				 Bit 7: must be set,
211 				     6: Self-powered,
212 				     5: Remote wakeup,
213 				     4..0: resvd */
214 	0x00,       /*  __u8  MaxPower; */
215 
216 	/* USB 1.1:
217 	 * USB 2.0, single TT organization (mandatory):
218 	 *	one interface, protocol 0
219 	 *
220 	 * USB 2.0, multiple TT organization (optional):
221 	 *	two interfaces, protocols 1 (like single TT)
222 	 *	and 2 (multiple TT mode) ... config is
223 	 *	sometimes settable
224 	 *	NOT IMPLEMENTED
225 	 */
226 
227 	/* one interface */
228 	0x09,       /*  __u8  if_bLength; */
229 	0x04,       /*  __u8  if_bDescriptorType; Interface */
230 	0x00,       /*  __u8  if_bInterfaceNumber; */
231 	0x00,       /*  __u8  if_bAlternateSetting; */
232 	0x01,       /*  __u8  if_bNumEndpoints; */
233 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
234 	0x00,       /*  __u8  if_bInterfaceSubClass; */
235 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
236 	0x00,       /*  __u8  if_iInterface; */
237 
238 	/* one endpoint (status change endpoint) */
239 	0x07,       /*  __u8  ep_bLength; */
240 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
241 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
242  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
243  	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
244 	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
245 };
246 
247 static const u8 hs_rh_config_descriptor [] = {
248 
249 	/* one configuration */
250 	0x09,       /*  __u8  bLength; */
251 	0x02,       /*  __u8  bDescriptorType; Configuration */
252 	0x19, 0x00, /*  __le16 wTotalLength; */
253 	0x01,       /*  __u8  bNumInterfaces; (1) */
254 	0x01,       /*  __u8  bConfigurationValue; */
255 	0x00,       /*  __u8  iConfiguration; */
256 	0xc0,       /*  __u8  bmAttributes;
257 				 Bit 7: must be set,
258 				     6: Self-powered,
259 				     5: Remote wakeup,
260 				     4..0: resvd */
261 	0x00,       /*  __u8  MaxPower; */
262 
263 	/* USB 1.1:
264 	 * USB 2.0, single TT organization (mandatory):
265 	 *	one interface, protocol 0
266 	 *
267 	 * USB 2.0, multiple TT organization (optional):
268 	 *	two interfaces, protocols 1 (like single TT)
269 	 *	and 2 (multiple TT mode) ... config is
270 	 *	sometimes settable
271 	 *	NOT IMPLEMENTED
272 	 */
273 
274 	/* one interface */
275 	0x09,       /*  __u8  if_bLength; */
276 	0x04,       /*  __u8  if_bDescriptorType; Interface */
277 	0x00,       /*  __u8  if_bInterfaceNumber; */
278 	0x00,       /*  __u8  if_bAlternateSetting; */
279 	0x01,       /*  __u8  if_bNumEndpoints; */
280 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
281 	0x00,       /*  __u8  if_bInterfaceSubClass; */
282 	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
283 	0x00,       /*  __u8  if_iInterface; */
284 
285 	/* one endpoint (status change endpoint) */
286 	0x07,       /*  __u8  ep_bLength; */
287 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
288 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
289  	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
290 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
291 		     * see hub.c:hub_configure() for details. */
292 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
293 	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
294 };
295 
296 static const u8 ss_rh_config_descriptor[] = {
297 	/* one configuration */
298 	0x09,       /*  __u8  bLength; */
299 	0x02,       /*  __u8  bDescriptorType; Configuration */
300 	0x1f, 0x00, /*  __le16 wTotalLength; */
301 	0x01,       /*  __u8  bNumInterfaces; (1) */
302 	0x01,       /*  __u8  bConfigurationValue; */
303 	0x00,       /*  __u8  iConfiguration; */
304 	0xc0,       /*  __u8  bmAttributes;
305 				 Bit 7: must be set,
306 				     6: Self-powered,
307 				     5: Remote wakeup,
308 				     4..0: resvd */
309 	0x00,       /*  __u8  MaxPower; */
310 
311 	/* one interface */
312 	0x09,       /*  __u8  if_bLength; */
313 	0x04,       /*  __u8  if_bDescriptorType; Interface */
314 	0x00,       /*  __u8  if_bInterfaceNumber; */
315 	0x00,       /*  __u8  if_bAlternateSetting; */
316 	0x01,       /*  __u8  if_bNumEndpoints; */
317 	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
318 	0x00,       /*  __u8  if_bInterfaceSubClass; */
319 	0x00,       /*  __u8  if_bInterfaceProtocol; */
320 	0x00,       /*  __u8  if_iInterface; */
321 
322 	/* one endpoint (status change endpoint) */
323 	0x07,       /*  __u8  ep_bLength; */
324 	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
325 	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
326 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
327 		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
328 		     * see hub.c:hub_configure() for details. */
329 	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
330 	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
331 
332 	/* one SuperSpeed endpoint companion descriptor */
333 	0x06,        /* __u8 ss_bLength */
334 	0x30,        /* __u8 ss_bDescriptorType; SuperSpeed EP Companion */
335 	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
336 	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
337 	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
338 };
339 
340 /* authorized_default behaviour:
341  * -1 is authorized for all devices except wireless (old behaviour)
342  * 0 is unauthorized for all devices
343  * 1 is authorized for all devices
344  */
345 static int authorized_default = -1;
346 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
347 MODULE_PARM_DESC(authorized_default,
348 		"Default USB device authorization: 0 is not authorized, 1 is "
349 		"authorized, -1 is authorized except for wireless USB (default, "
350 		"old behaviour");
351 /*-------------------------------------------------------------------------*/
352 
353 /**
354  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
355  * @s: Null-terminated ASCII (actually ISO-8859-1) string
356  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
357  * @len: Length (in bytes; may be odd) of descriptor buffer.
358  *
359  * The return value is the number of bytes filled in: 2 + 2*strlen(s) or
360  * buflen, whichever is less.
361  *
362  * USB String descriptors can contain at most 126 characters; input
363  * strings longer than that are truncated.
364  */
365 static unsigned
366 ascii2desc(char const *s, u8 *buf, unsigned len)
367 {
368 	unsigned n, t = 2 + 2*strlen(s);
369 
370 	if (t > 254)
371 		t = 254;	/* Longest possible UTF string descriptor */
372 	if (len > t)
373 		len = t;
374 
375 	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
376 
377 	n = len;
378 	while (n--) {
379 		*buf++ = t;
380 		if (!n--)
381 			break;
382 		*buf++ = t >> 8;
383 		t = (unsigned char)*s++;
384 	}
385 	return len;
386 }
387 
388 /**
389  * rh_string() - provides string descriptors for root hub
390  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
391  * @hcd: the host controller for this root hub
392  * @data: buffer for output packet
393  * @len: length of the provided buffer
394  *
395  * Produces either a manufacturer, product or serial number string for the
396  * virtual root hub device.
397  * Returns the number of bytes filled in: the length of the descriptor or
398  * of the provided buffer, whichever is less.
399  */
400 static unsigned
401 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
402 {
403 	char buf[100];
404 	char const *s;
405 	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
406 
407 	// language ids
408 	switch (id) {
409 	case 0:
410 		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
411 		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
412 		if (len > 4)
413 			len = 4;
414 		memcpy(data, langids, len);
415 		return len;
416 	case 1:
417 		/* Serial number */
418 		s = hcd->self.bus_name;
419 		break;
420 	case 2:
421 		/* Product name */
422 		s = hcd->product_desc;
423 		break;
424 	case 3:
425 		/* Manufacturer */
426 		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
427 			init_utsname()->release, hcd->driver->description);
428 		s = buf;
429 		break;
430 	default:
431 		/* Can't happen; caller guarantees it */
432 		return 0;
433 	}
434 
435 	return ascii2desc(s, data, len);
436 }
437 
438 
439 /* Root hub control transfers execute synchronously */
440 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
441 {
442 	struct usb_ctrlrequest *cmd;
443  	u16		typeReq, wValue, wIndex, wLength;
444 	u8		*ubuf = urb->transfer_buffer;
445 	/*
446 	 * tbuf should be as big as the BOS descriptor and
447 	 * the USB hub descriptor.
448 	 */
449 	u8		tbuf[USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE]
450 		__attribute__((aligned(4)));
451 	const u8	*bufp = tbuf;
452 	unsigned	len = 0;
453 	int		status;
454 	u8		patch_wakeup = 0;
455 	u8		patch_protocol = 0;
456 
457 	might_sleep();
458 
459 	spin_lock_irq(&hcd_root_hub_lock);
460 	status = usb_hcd_link_urb_to_ep(hcd, urb);
461 	spin_unlock_irq(&hcd_root_hub_lock);
462 	if (status)
463 		return status;
464 	urb->hcpriv = hcd;	/* Indicate it's queued */
465 
466 	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
467 	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
468 	wValue   = le16_to_cpu (cmd->wValue);
469 	wIndex   = le16_to_cpu (cmd->wIndex);
470 	wLength  = le16_to_cpu (cmd->wLength);
471 
472 	if (wLength > urb->transfer_buffer_length)
473 		goto error;
474 
475 	urb->actual_length = 0;
476 	switch (typeReq) {
477 
478 	/* DEVICE REQUESTS */
479 
480 	/* The root hub's remote wakeup enable bit is implemented using
481 	 * driver model wakeup flags.  If this system supports wakeup
482 	 * through USB, userspace may change the default "allow wakeup"
483 	 * policy through sysfs or these calls.
484 	 *
485 	 * Most root hubs support wakeup from downstream devices, for
486 	 * runtime power management (disabling USB clocks and reducing
487 	 * VBUS power usage).  However, not all of them do so; silicon,
488 	 * board, and BIOS bugs here are not uncommon, so these can't
489 	 * be treated quite like external hubs.
490 	 *
491 	 * Likewise, not all root hubs will pass wakeup events upstream,
492 	 * to wake up the whole system.  So don't assume root hub and
493 	 * controller capabilities are identical.
494 	 */
495 
496 	case DeviceRequest | USB_REQ_GET_STATUS:
497 		tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
498 					<< USB_DEVICE_REMOTE_WAKEUP)
499 				| (1 << USB_DEVICE_SELF_POWERED);
500 		tbuf [1] = 0;
501 		len = 2;
502 		break;
503 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
504 		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
505 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
506 		else
507 			goto error;
508 		break;
509 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
510 		if (device_can_wakeup(&hcd->self.root_hub->dev)
511 				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
512 			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
513 		else
514 			goto error;
515 		break;
516 	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
517 		tbuf [0] = 1;
518 		len = 1;
519 			/* FALLTHROUGH */
520 	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
521 		break;
522 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
523 		switch (wValue & 0xff00) {
524 		case USB_DT_DEVICE << 8:
525 			switch (hcd->speed) {
526 			case HCD_USB3:
527 				bufp = usb3_rh_dev_descriptor;
528 				break;
529 			case HCD_USB2:
530 				bufp = usb2_rh_dev_descriptor;
531 				break;
532 			case HCD_USB11:
533 				bufp = usb11_rh_dev_descriptor;
534 				break;
535 			default:
536 				goto error;
537 			}
538 			len = 18;
539 			if (hcd->has_tt)
540 				patch_protocol = 1;
541 			break;
542 		case USB_DT_CONFIG << 8:
543 			switch (hcd->speed) {
544 			case HCD_USB3:
545 				bufp = ss_rh_config_descriptor;
546 				len = sizeof ss_rh_config_descriptor;
547 				break;
548 			case HCD_USB2:
549 				bufp = hs_rh_config_descriptor;
550 				len = sizeof hs_rh_config_descriptor;
551 				break;
552 			case HCD_USB11:
553 				bufp = fs_rh_config_descriptor;
554 				len = sizeof fs_rh_config_descriptor;
555 				break;
556 			default:
557 				goto error;
558 			}
559 			if (device_can_wakeup(&hcd->self.root_hub->dev))
560 				patch_wakeup = 1;
561 			break;
562 		case USB_DT_STRING << 8:
563 			if ((wValue & 0xff) < 4)
564 				urb->actual_length = rh_string(wValue & 0xff,
565 						hcd, ubuf, wLength);
566 			else /* unsupported IDs --> "protocol stall" */
567 				goto error;
568 			break;
569 		case USB_DT_BOS << 8:
570 			goto nongeneric;
571 		default:
572 			goto error;
573 		}
574 		break;
575 	case DeviceRequest | USB_REQ_GET_INTERFACE:
576 		tbuf [0] = 0;
577 		len = 1;
578 			/* FALLTHROUGH */
579 	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
580 		break;
581 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
582 		// wValue == urb->dev->devaddr
583 		dev_dbg (hcd->self.controller, "root hub device address %d\n",
584 			wValue);
585 		break;
586 
587 	/* INTERFACE REQUESTS (no defined feature/status flags) */
588 
589 	/* ENDPOINT REQUESTS */
590 
591 	case EndpointRequest | USB_REQ_GET_STATUS:
592 		// ENDPOINT_HALT flag
593 		tbuf [0] = 0;
594 		tbuf [1] = 0;
595 		len = 2;
596 			/* FALLTHROUGH */
597 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
598 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
599 		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
600 		break;
601 
602 	/* CLASS REQUESTS (and errors) */
603 
604 	default:
605 nongeneric:
606 		/* non-generic request */
607 		switch (typeReq) {
608 		case GetHubStatus:
609 		case GetPortStatus:
610 			len = 4;
611 			break;
612 		case GetHubDescriptor:
613 			len = sizeof (struct usb_hub_descriptor);
614 			break;
615 		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
616 			/* len is returned by hub_control */
617 			break;
618 		}
619 		status = hcd->driver->hub_control (hcd,
620 			typeReq, wValue, wIndex,
621 			tbuf, wLength);
622 		break;
623 error:
624 		/* "protocol stall" on error */
625 		status = -EPIPE;
626 	}
627 
628 	if (status < 0) {
629 		len = 0;
630 		if (status != -EPIPE) {
631 			dev_dbg (hcd->self.controller,
632 				"CTRL: TypeReq=0x%x val=0x%x "
633 				"idx=0x%x len=%d ==> %d\n",
634 				typeReq, wValue, wIndex,
635 				wLength, status);
636 		}
637 	} else if (status > 0) {
638 		/* hub_control may return the length of data copied. */
639 		len = status;
640 		status = 0;
641 	}
642 	if (len) {
643 		if (urb->transfer_buffer_length < len)
644 			len = urb->transfer_buffer_length;
645 		urb->actual_length = len;
646 		// always USB_DIR_IN, toward host
647 		memcpy (ubuf, bufp, len);
648 
649 		/* report whether RH hardware supports remote wakeup */
650 		if (patch_wakeup &&
651 				len > offsetof (struct usb_config_descriptor,
652 						bmAttributes))
653 			((struct usb_config_descriptor *)ubuf)->bmAttributes
654 				|= USB_CONFIG_ATT_WAKEUP;
655 
656 		/* report whether RH hardware has an integrated TT */
657 		if (patch_protocol &&
658 				len > offsetof(struct usb_device_descriptor,
659 						bDeviceProtocol))
660 			((struct usb_device_descriptor *) ubuf)->
661 				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
662 	}
663 
664 	/* any errors get returned through the urb completion */
665 	spin_lock_irq(&hcd_root_hub_lock);
666 	usb_hcd_unlink_urb_from_ep(hcd, urb);
667 
668 	/* This peculiar use of spinlocks echoes what real HC drivers do.
669 	 * Avoiding calls to local_irq_disable/enable makes the code
670 	 * RT-friendly.
671 	 */
672 	spin_unlock(&hcd_root_hub_lock);
673 	usb_hcd_giveback_urb(hcd, urb, status);
674 	spin_lock(&hcd_root_hub_lock);
675 
676 	spin_unlock_irq(&hcd_root_hub_lock);
677 	return 0;
678 }
679 
680 /*-------------------------------------------------------------------------*/
681 
682 /*
683  * Root Hub interrupt transfers are polled using a timer if the
684  * driver requests it; otherwise the driver is responsible for
685  * calling usb_hcd_poll_rh_status() when an event occurs.
686  *
687  * Completions are called in_interrupt(), but they may or may not
688  * be in_irq().
689  */
690 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
691 {
692 	struct urb	*urb;
693 	int		length;
694 	unsigned long	flags;
695 	char		buffer[6];	/* Any root hubs with > 31 ports? */
696 
697 	if (unlikely(!hcd->rh_pollable))
698 		return;
699 	if (!hcd->uses_new_polling && !hcd->status_urb)
700 		return;
701 
702 	length = hcd->driver->hub_status_data(hcd, buffer);
703 	if (length > 0) {
704 
705 		/* try to complete the status urb */
706 		spin_lock_irqsave(&hcd_root_hub_lock, flags);
707 		urb = hcd->status_urb;
708 		if (urb) {
709 			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
710 			hcd->status_urb = NULL;
711 			urb->actual_length = length;
712 			memcpy(urb->transfer_buffer, buffer, length);
713 
714 			usb_hcd_unlink_urb_from_ep(hcd, urb);
715 			spin_unlock(&hcd_root_hub_lock);
716 			usb_hcd_giveback_urb(hcd, urb, 0);
717 			spin_lock(&hcd_root_hub_lock);
718 		} else {
719 			length = 0;
720 			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
721 		}
722 		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
723 	}
724 
725 	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
726 	 * exceed that limit if HZ is 100. The math is more clunky than
727 	 * maybe expected, this is to make sure that all timers for USB devices
728 	 * fire at the same time to give the CPU a break in between */
729 	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
730 			(length == 0 && hcd->status_urb != NULL))
731 		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
732 }
733 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
734 
735 /* timer callback */
736 static void rh_timer_func (unsigned long _hcd)
737 {
738 	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
739 }
740 
741 /*-------------------------------------------------------------------------*/
742 
743 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
744 {
745 	int		retval;
746 	unsigned long	flags;
747 	unsigned	len = 1 + (urb->dev->maxchild / 8);
748 
749 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
750 	if (hcd->status_urb || urb->transfer_buffer_length < len) {
751 		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
752 		retval = -EINVAL;
753 		goto done;
754 	}
755 
756 	retval = usb_hcd_link_urb_to_ep(hcd, urb);
757 	if (retval)
758 		goto done;
759 
760 	hcd->status_urb = urb;
761 	urb->hcpriv = hcd;	/* indicate it's queued */
762 	if (!hcd->uses_new_polling)
763 		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
764 
765 	/* If a status change has already occurred, report it ASAP */
766 	else if (HCD_POLL_PENDING(hcd))
767 		mod_timer(&hcd->rh_timer, jiffies);
768 	retval = 0;
769  done:
770 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
771 	return retval;
772 }
773 
774 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
775 {
776 	if (usb_endpoint_xfer_int(&urb->ep->desc))
777 		return rh_queue_status (hcd, urb);
778 	if (usb_endpoint_xfer_control(&urb->ep->desc))
779 		return rh_call_control (hcd, urb);
780 	return -EINVAL;
781 }
782 
783 /*-------------------------------------------------------------------------*/
784 
785 /* Unlinks of root-hub control URBs are legal, but they don't do anything
786  * since these URBs always execute synchronously.
787  */
788 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
789 {
790 	unsigned long	flags;
791 	int		rc;
792 
793 	spin_lock_irqsave(&hcd_root_hub_lock, flags);
794 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
795 	if (rc)
796 		goto done;
797 
798 	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
799 		;	/* Do nothing */
800 
801 	} else {				/* Status URB */
802 		if (!hcd->uses_new_polling)
803 			del_timer (&hcd->rh_timer);
804 		if (urb == hcd->status_urb) {
805 			hcd->status_urb = NULL;
806 			usb_hcd_unlink_urb_from_ep(hcd, urb);
807 
808 			spin_unlock(&hcd_root_hub_lock);
809 			usb_hcd_giveback_urb(hcd, urb, status);
810 			spin_lock(&hcd_root_hub_lock);
811 		}
812 	}
813  done:
814 	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
815 	return rc;
816 }
817 
818 
819 
820 /*
821  * Show & store the current value of authorized_default
822  */
823 static ssize_t usb_host_authorized_default_show(struct device *dev,
824 						struct device_attribute *attr,
825 						char *buf)
826 {
827 	struct usb_device *rh_usb_dev = to_usb_device(dev);
828 	struct usb_bus *usb_bus = rh_usb_dev->bus;
829 	struct usb_hcd *usb_hcd;
830 
831 	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
832 		return -ENODEV;
833 	usb_hcd = bus_to_hcd(usb_bus);
834 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
835 }
836 
837 static ssize_t usb_host_authorized_default_store(struct device *dev,
838 						 struct device_attribute *attr,
839 						 const char *buf, size_t size)
840 {
841 	ssize_t result;
842 	unsigned val;
843 	struct usb_device *rh_usb_dev = to_usb_device(dev);
844 	struct usb_bus *usb_bus = rh_usb_dev->bus;
845 	struct usb_hcd *usb_hcd;
846 
847 	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
848 		return -ENODEV;
849 	usb_hcd = bus_to_hcd(usb_bus);
850 	result = sscanf(buf, "%u\n", &val);
851 	if (result == 1) {
852 		usb_hcd->authorized_default = val? 1 : 0;
853 		result = size;
854 	}
855 	else
856 		result = -EINVAL;
857 	return result;
858 }
859 
860 static DEVICE_ATTR(authorized_default, 0644,
861 	    usb_host_authorized_default_show,
862 	    usb_host_authorized_default_store);
863 
864 
865 /* Group all the USB bus attributes */
866 static struct attribute *usb_bus_attrs[] = {
867 		&dev_attr_authorized_default.attr,
868 		NULL,
869 };
870 
871 static struct attribute_group usb_bus_attr_group = {
872 	.name = NULL,	/* we want them in the same directory */
873 	.attrs = usb_bus_attrs,
874 };
875 
876 
877 
878 /*-------------------------------------------------------------------------*/
879 
880 /**
881  * usb_bus_init - shared initialization code
882  * @bus: the bus structure being initialized
883  *
884  * This code is used to initialize a usb_bus structure, memory for which is
885  * separately managed.
886  */
887 static void usb_bus_init (struct usb_bus *bus)
888 {
889 	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
890 
891 	bus->devnum_next = 1;
892 
893 	bus->root_hub = NULL;
894 	bus->busnum = -1;
895 	bus->bandwidth_allocated = 0;
896 	bus->bandwidth_int_reqs  = 0;
897 	bus->bandwidth_isoc_reqs = 0;
898 
899 	INIT_LIST_HEAD (&bus->bus_list);
900 }
901 
902 /*-------------------------------------------------------------------------*/
903 
904 /**
905  * usb_register_bus - registers the USB host controller with the usb core
906  * @bus: pointer to the bus to register
907  * Context: !in_interrupt()
908  *
909  * Assigns a bus number, and links the controller into usbcore data
910  * structures so that it can be seen by scanning the bus list.
911  */
912 static int usb_register_bus(struct usb_bus *bus)
913 {
914 	int result = -E2BIG;
915 	int busnum;
916 
917 	mutex_lock(&usb_bus_list_lock);
918 	busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
919 	if (busnum >= USB_MAXBUS) {
920 		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
921 		goto error_find_busnum;
922 	}
923 	set_bit (busnum, busmap.busmap);
924 	bus->busnum = busnum;
925 
926 	/* Add it to the local list of buses */
927 	list_add (&bus->bus_list, &usb_bus_list);
928 	mutex_unlock(&usb_bus_list_lock);
929 
930 	usb_notify_add_bus(bus);
931 
932 	dev_info (bus->controller, "new USB bus registered, assigned bus "
933 		  "number %d\n", bus->busnum);
934 	return 0;
935 
936 error_find_busnum:
937 	mutex_unlock(&usb_bus_list_lock);
938 	return result;
939 }
940 
941 /**
942  * usb_deregister_bus - deregisters the USB host controller
943  * @bus: pointer to the bus to deregister
944  * Context: !in_interrupt()
945  *
946  * Recycles the bus number, and unlinks the controller from usbcore data
947  * structures so that it won't be seen by scanning the bus list.
948  */
949 static void usb_deregister_bus (struct usb_bus *bus)
950 {
951 	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
952 
953 	/*
954 	 * NOTE: make sure that all the devices are removed by the
955 	 * controller code, as well as having it call this when cleaning
956 	 * itself up
957 	 */
958 	mutex_lock(&usb_bus_list_lock);
959 	list_del (&bus->bus_list);
960 	mutex_unlock(&usb_bus_list_lock);
961 
962 	usb_notify_remove_bus(bus);
963 
964 	clear_bit (bus->busnum, busmap.busmap);
965 }
966 
967 /**
968  * register_root_hub - called by usb_add_hcd() to register a root hub
969  * @hcd: host controller for this root hub
970  *
971  * This function registers the root hub with the USB subsystem.  It sets up
972  * the device properly in the device tree and then calls usb_new_device()
973  * to register the usb device.  It also assigns the root hub's USB address
974  * (always 1).
975  */
976 static int register_root_hub(struct usb_hcd *hcd)
977 {
978 	struct device *parent_dev = hcd->self.controller;
979 	struct usb_device *usb_dev = hcd->self.root_hub;
980 	const int devnum = 1;
981 	int retval;
982 
983 	usb_dev->devnum = devnum;
984 	usb_dev->bus->devnum_next = devnum + 1;
985 	memset (&usb_dev->bus->devmap.devicemap, 0,
986 			sizeof usb_dev->bus->devmap.devicemap);
987 	set_bit (devnum, usb_dev->bus->devmap.devicemap);
988 	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
989 
990 	mutex_lock(&usb_bus_list_lock);
991 
992 	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
993 	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
994 	if (retval != sizeof usb_dev->descriptor) {
995 		mutex_unlock(&usb_bus_list_lock);
996 		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
997 				dev_name(&usb_dev->dev), retval);
998 		return (retval < 0) ? retval : -EMSGSIZE;
999 	}
1000 	if (usb_dev->speed == USB_SPEED_SUPER) {
1001 		retval = usb_get_bos_descriptor(usb_dev);
1002 		if (retval < 0) {
1003 			mutex_unlock(&usb_bus_list_lock);
1004 			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1005 					dev_name(&usb_dev->dev), retval);
1006 			return retval;
1007 		}
1008 	}
1009 
1010 	retval = usb_new_device (usb_dev);
1011 	if (retval) {
1012 		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1013 				dev_name(&usb_dev->dev), retval);
1014 	} else {
1015 		spin_lock_irq (&hcd_root_hub_lock);
1016 		hcd->rh_registered = 1;
1017 		spin_unlock_irq (&hcd_root_hub_lock);
1018 
1019 		/* Did the HC die before the root hub was registered? */
1020 		if (HCD_DEAD(hcd))
1021 			usb_hc_died (hcd);	/* This time clean up */
1022 	}
1023 	mutex_unlock(&usb_bus_list_lock);
1024 
1025 	return retval;
1026 }
1027 
1028 
1029 /*-------------------------------------------------------------------------*/
1030 
1031 /**
1032  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1033  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1034  * @is_input: true iff the transaction sends data to the host
1035  * @isoc: true for isochronous transactions, false for interrupt ones
1036  * @bytecount: how many bytes in the transaction.
1037  *
1038  * Returns approximate bus time in nanoseconds for a periodic transaction.
1039  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1040  * scheduled in software, this function is only used for such scheduling.
1041  */
1042 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1043 {
1044 	unsigned long	tmp;
1045 
1046 	switch (speed) {
1047 	case USB_SPEED_LOW: 	/* INTR only */
1048 		if (is_input) {
1049 			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1050 			return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1051 		} else {
1052 			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1053 			return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1054 		}
1055 	case USB_SPEED_FULL:	/* ISOC or INTR */
1056 		if (isoc) {
1057 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1058 			return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
1059 		} else {
1060 			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1061 			return (9107L + BW_HOST_DELAY + tmp);
1062 		}
1063 	case USB_SPEED_HIGH:	/* ISOC or INTR */
1064 		// FIXME adjust for input vs output
1065 		if (isoc)
1066 			tmp = HS_NSECS_ISO (bytecount);
1067 		else
1068 			tmp = HS_NSECS (bytecount);
1069 		return tmp;
1070 	default:
1071 		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1072 		return -1;
1073 	}
1074 }
1075 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1076 
1077 
1078 /*-------------------------------------------------------------------------*/
1079 
1080 /*
1081  * Generic HC operations.
1082  */
1083 
1084 /*-------------------------------------------------------------------------*/
1085 
1086 /**
1087  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1088  * @hcd: host controller to which @urb was submitted
1089  * @urb: URB being submitted
1090  *
1091  * Host controller drivers should call this routine in their enqueue()
1092  * method.  The HCD's private spinlock must be held and interrupts must
1093  * be disabled.  The actions carried out here are required for URB
1094  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1095  *
1096  * Returns 0 for no error, otherwise a negative error code (in which case
1097  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1098  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1099  * the private spinlock and returning.
1100  */
1101 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1102 {
1103 	int		rc = 0;
1104 
1105 	spin_lock(&hcd_urb_list_lock);
1106 
1107 	/* Check that the URB isn't being killed */
1108 	if (unlikely(atomic_read(&urb->reject))) {
1109 		rc = -EPERM;
1110 		goto done;
1111 	}
1112 
1113 	if (unlikely(!urb->ep->enabled)) {
1114 		rc = -ENOENT;
1115 		goto done;
1116 	}
1117 
1118 	if (unlikely(!urb->dev->can_submit)) {
1119 		rc = -EHOSTUNREACH;
1120 		goto done;
1121 	}
1122 
1123 	/*
1124 	 * Check the host controller's state and add the URB to the
1125 	 * endpoint's queue.
1126 	 */
1127 	if (HCD_RH_RUNNING(hcd)) {
1128 		urb->unlinked = 0;
1129 		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1130 	} else {
1131 		rc = -ESHUTDOWN;
1132 		goto done;
1133 	}
1134  done:
1135 	spin_unlock(&hcd_urb_list_lock);
1136 	return rc;
1137 }
1138 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1139 
1140 /**
1141  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1142  * @hcd: host controller to which @urb was submitted
1143  * @urb: URB being checked for unlinkability
1144  * @status: error code to store in @urb if the unlink succeeds
1145  *
1146  * Host controller drivers should call this routine in their dequeue()
1147  * method.  The HCD's private spinlock must be held and interrupts must
1148  * be disabled.  The actions carried out here are required for making
1149  * sure than an unlink is valid.
1150  *
1151  * Returns 0 for no error, otherwise a negative error code (in which case
1152  * the dequeue() method must fail).  The possible error codes are:
1153  *
1154  *	-EIDRM: @urb was not submitted or has already completed.
1155  *		The completion function may not have been called yet.
1156  *
1157  *	-EBUSY: @urb has already been unlinked.
1158  */
1159 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1160 		int status)
1161 {
1162 	struct list_head	*tmp;
1163 
1164 	/* insist the urb is still queued */
1165 	list_for_each(tmp, &urb->ep->urb_list) {
1166 		if (tmp == &urb->urb_list)
1167 			break;
1168 	}
1169 	if (tmp != &urb->urb_list)
1170 		return -EIDRM;
1171 
1172 	/* Any status except -EINPROGRESS means something already started to
1173 	 * unlink this URB from the hardware.  So there's no more work to do.
1174 	 */
1175 	if (urb->unlinked)
1176 		return -EBUSY;
1177 	urb->unlinked = status;
1178 	return 0;
1179 }
1180 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1181 
1182 /**
1183  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1184  * @hcd: host controller to which @urb was submitted
1185  * @urb: URB being unlinked
1186  *
1187  * Host controller drivers should call this routine before calling
1188  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1189  * interrupts must be disabled.  The actions carried out here are required
1190  * for URB completion.
1191  */
1192 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1193 {
1194 	/* clear all state linking urb to this dev (and hcd) */
1195 	spin_lock(&hcd_urb_list_lock);
1196 	list_del_init(&urb->urb_list);
1197 	spin_unlock(&hcd_urb_list_lock);
1198 }
1199 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1200 
1201 /*
1202  * Some usb host controllers can only perform dma using a small SRAM area.
1203  * The usb core itself is however optimized for host controllers that can dma
1204  * using regular system memory - like pci devices doing bus mastering.
1205  *
1206  * To support host controllers with limited dma capabilites we provide dma
1207  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1208  * For this to work properly the host controller code must first use the
1209  * function dma_declare_coherent_memory() to point out which memory area
1210  * that should be used for dma allocations.
1211  *
1212  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1213  * dma using dma_alloc_coherent() which in turn allocates from the memory
1214  * area pointed out with dma_declare_coherent_memory().
1215  *
1216  * So, to summarize...
1217  *
1218  * - We need "local" memory, canonical example being
1219  *   a small SRAM on a discrete controller being the
1220  *   only memory that the controller can read ...
1221  *   (a) "normal" kernel memory is no good, and
1222  *   (b) there's not enough to share
1223  *
1224  * - The only *portable* hook for such stuff in the
1225  *   DMA framework is dma_declare_coherent_memory()
1226  *
1227  * - So we use that, even though the primary requirement
1228  *   is that the memory be "local" (hence addressible
1229  *   by that device), not "coherent".
1230  *
1231  */
1232 
1233 static int hcd_alloc_coherent(struct usb_bus *bus,
1234 			      gfp_t mem_flags, dma_addr_t *dma_handle,
1235 			      void **vaddr_handle, size_t size,
1236 			      enum dma_data_direction dir)
1237 {
1238 	unsigned char *vaddr;
1239 
1240 	if (*vaddr_handle == NULL) {
1241 		WARN_ON_ONCE(1);
1242 		return -EFAULT;
1243 	}
1244 
1245 	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1246 				 mem_flags, dma_handle);
1247 	if (!vaddr)
1248 		return -ENOMEM;
1249 
1250 	/*
1251 	 * Store the virtual address of the buffer at the end
1252 	 * of the allocated dma buffer. The size of the buffer
1253 	 * may be uneven so use unaligned functions instead
1254 	 * of just rounding up. It makes sense to optimize for
1255 	 * memory footprint over access speed since the amount
1256 	 * of memory available for dma may be limited.
1257 	 */
1258 	put_unaligned((unsigned long)*vaddr_handle,
1259 		      (unsigned long *)(vaddr + size));
1260 
1261 	if (dir == DMA_TO_DEVICE)
1262 		memcpy(vaddr, *vaddr_handle, size);
1263 
1264 	*vaddr_handle = vaddr;
1265 	return 0;
1266 }
1267 
1268 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1269 			      void **vaddr_handle, size_t size,
1270 			      enum dma_data_direction dir)
1271 {
1272 	unsigned char *vaddr = *vaddr_handle;
1273 
1274 	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1275 
1276 	if (dir == DMA_FROM_DEVICE)
1277 		memcpy(vaddr, *vaddr_handle, size);
1278 
1279 	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1280 
1281 	*vaddr_handle = vaddr;
1282 	*dma_handle = 0;
1283 }
1284 
1285 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1286 {
1287 	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1288 		dma_unmap_single(hcd->self.controller,
1289 				urb->setup_dma,
1290 				sizeof(struct usb_ctrlrequest),
1291 				DMA_TO_DEVICE);
1292 	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1293 		hcd_free_coherent(urb->dev->bus,
1294 				&urb->setup_dma,
1295 				(void **) &urb->setup_packet,
1296 				sizeof(struct usb_ctrlrequest),
1297 				DMA_TO_DEVICE);
1298 
1299 	/* Make it safe to call this routine more than once */
1300 	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1301 }
1302 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1303 
1304 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1305 {
1306 	if (hcd->driver->unmap_urb_for_dma)
1307 		hcd->driver->unmap_urb_for_dma(hcd, urb);
1308 	else
1309 		usb_hcd_unmap_urb_for_dma(hcd, urb);
1310 }
1311 
1312 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1313 {
1314 	enum dma_data_direction dir;
1315 
1316 	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1317 
1318 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1319 	if (urb->transfer_flags & URB_DMA_MAP_SG)
1320 		dma_unmap_sg(hcd->self.controller,
1321 				urb->sg,
1322 				urb->num_sgs,
1323 				dir);
1324 	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1325 		dma_unmap_page(hcd->self.controller,
1326 				urb->transfer_dma,
1327 				urb->transfer_buffer_length,
1328 				dir);
1329 	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1330 		dma_unmap_single(hcd->self.controller,
1331 				urb->transfer_dma,
1332 				urb->transfer_buffer_length,
1333 				dir);
1334 	else if (urb->transfer_flags & URB_MAP_LOCAL)
1335 		hcd_free_coherent(urb->dev->bus,
1336 				&urb->transfer_dma,
1337 				&urb->transfer_buffer,
1338 				urb->transfer_buffer_length,
1339 				dir);
1340 
1341 	/* Make it safe to call this routine more than once */
1342 	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1343 			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1344 }
1345 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1346 
1347 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1348 			   gfp_t mem_flags)
1349 {
1350 	if (hcd->driver->map_urb_for_dma)
1351 		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1352 	else
1353 		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1354 }
1355 
1356 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1357 			    gfp_t mem_flags)
1358 {
1359 	enum dma_data_direction dir;
1360 	int ret = 0;
1361 
1362 	/* Map the URB's buffers for DMA access.
1363 	 * Lower level HCD code should use *_dma exclusively,
1364 	 * unless it uses pio or talks to another transport,
1365 	 * or uses the provided scatter gather list for bulk.
1366 	 */
1367 
1368 	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1369 		if (hcd->self.uses_pio_for_control)
1370 			return ret;
1371 		if (hcd->self.uses_dma) {
1372 			urb->setup_dma = dma_map_single(
1373 					hcd->self.controller,
1374 					urb->setup_packet,
1375 					sizeof(struct usb_ctrlrequest),
1376 					DMA_TO_DEVICE);
1377 			if (dma_mapping_error(hcd->self.controller,
1378 						urb->setup_dma))
1379 				return -EAGAIN;
1380 			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1381 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1382 			ret = hcd_alloc_coherent(
1383 					urb->dev->bus, mem_flags,
1384 					&urb->setup_dma,
1385 					(void **)&urb->setup_packet,
1386 					sizeof(struct usb_ctrlrequest),
1387 					DMA_TO_DEVICE);
1388 			if (ret)
1389 				return ret;
1390 			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1391 		}
1392 	}
1393 
1394 	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1395 	if (urb->transfer_buffer_length != 0
1396 	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1397 		if (hcd->self.uses_dma) {
1398 			if (urb->num_sgs) {
1399 				int n;
1400 
1401 				/* We don't support sg for isoc transfers ! */
1402 				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1403 					WARN_ON(1);
1404 					return -EINVAL;
1405 				}
1406 
1407 				n = dma_map_sg(
1408 						hcd->self.controller,
1409 						urb->sg,
1410 						urb->num_sgs,
1411 						dir);
1412 				if (n <= 0)
1413 					ret = -EAGAIN;
1414 				else
1415 					urb->transfer_flags |= URB_DMA_MAP_SG;
1416 				urb->num_mapped_sgs = n;
1417 				if (n != urb->num_sgs)
1418 					urb->transfer_flags |=
1419 							URB_DMA_SG_COMBINED;
1420 			} else if (urb->sg) {
1421 				struct scatterlist *sg = urb->sg;
1422 				urb->transfer_dma = dma_map_page(
1423 						hcd->self.controller,
1424 						sg_page(sg),
1425 						sg->offset,
1426 						urb->transfer_buffer_length,
1427 						dir);
1428 				if (dma_mapping_error(hcd->self.controller,
1429 						urb->transfer_dma))
1430 					ret = -EAGAIN;
1431 				else
1432 					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1433 			} else {
1434 				urb->transfer_dma = dma_map_single(
1435 						hcd->self.controller,
1436 						urb->transfer_buffer,
1437 						urb->transfer_buffer_length,
1438 						dir);
1439 				if (dma_mapping_error(hcd->self.controller,
1440 						urb->transfer_dma))
1441 					ret = -EAGAIN;
1442 				else
1443 					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1444 			}
1445 		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1446 			ret = hcd_alloc_coherent(
1447 					urb->dev->bus, mem_flags,
1448 					&urb->transfer_dma,
1449 					&urb->transfer_buffer,
1450 					urb->transfer_buffer_length,
1451 					dir);
1452 			if (ret == 0)
1453 				urb->transfer_flags |= URB_MAP_LOCAL;
1454 		}
1455 		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1456 				URB_SETUP_MAP_LOCAL)))
1457 			usb_hcd_unmap_urb_for_dma(hcd, urb);
1458 	}
1459 	return ret;
1460 }
1461 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1462 
1463 /*-------------------------------------------------------------------------*/
1464 
1465 /* may be called in any context with a valid urb->dev usecount
1466  * caller surrenders "ownership" of urb
1467  * expects usb_submit_urb() to have sanity checked and conditioned all
1468  * inputs in the urb
1469  */
1470 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1471 {
1472 	int			status;
1473 	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1474 
1475 	/* increment urb's reference count as part of giving it to the HCD
1476 	 * (which will control it).  HCD guarantees that it either returns
1477 	 * an error or calls giveback(), but not both.
1478 	 */
1479 	usb_get_urb(urb);
1480 	atomic_inc(&urb->use_count);
1481 	atomic_inc(&urb->dev->urbnum);
1482 	usbmon_urb_submit(&hcd->self, urb);
1483 
1484 	/* NOTE requirements on root-hub callers (usbfs and the hub
1485 	 * driver, for now):  URBs' urb->transfer_buffer must be
1486 	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1487 	 * they could clobber root hub response data.  Also, control
1488 	 * URBs must be submitted in process context with interrupts
1489 	 * enabled.
1490 	 */
1491 
1492 	if (is_root_hub(urb->dev)) {
1493 		status = rh_urb_enqueue(hcd, urb);
1494 	} else {
1495 		status = map_urb_for_dma(hcd, urb, mem_flags);
1496 		if (likely(status == 0)) {
1497 			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1498 			if (unlikely(status))
1499 				unmap_urb_for_dma(hcd, urb);
1500 		}
1501 	}
1502 
1503 	if (unlikely(status)) {
1504 		usbmon_urb_submit_error(&hcd->self, urb, status);
1505 		urb->hcpriv = NULL;
1506 		INIT_LIST_HEAD(&urb->urb_list);
1507 		atomic_dec(&urb->use_count);
1508 		atomic_dec(&urb->dev->urbnum);
1509 		if (atomic_read(&urb->reject))
1510 			wake_up(&usb_kill_urb_queue);
1511 		usb_put_urb(urb);
1512 	}
1513 	return status;
1514 }
1515 
1516 /*-------------------------------------------------------------------------*/
1517 
1518 /* this makes the hcd giveback() the urb more quickly, by kicking it
1519  * off hardware queues (which may take a while) and returning it as
1520  * soon as practical.  we've already set up the urb's return status,
1521  * but we can't know if the callback completed already.
1522  */
1523 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1524 {
1525 	int		value;
1526 
1527 	if (is_root_hub(urb->dev))
1528 		value = usb_rh_urb_dequeue(hcd, urb, status);
1529 	else {
1530 
1531 		/* The only reason an HCD might fail this call is if
1532 		 * it has not yet fully queued the urb to begin with.
1533 		 * Such failures should be harmless. */
1534 		value = hcd->driver->urb_dequeue(hcd, urb, status);
1535 	}
1536 	return value;
1537 }
1538 
1539 /*
1540  * called in any context
1541  *
1542  * caller guarantees urb won't be recycled till both unlink()
1543  * and the urb's completion function return
1544  */
1545 int usb_hcd_unlink_urb (struct urb *urb, int status)
1546 {
1547 	struct usb_hcd		*hcd;
1548 	int			retval = -EIDRM;
1549 	unsigned long		flags;
1550 
1551 	/* Prevent the device and bus from going away while
1552 	 * the unlink is carried out.  If they are already gone
1553 	 * then urb->use_count must be 0, since disconnected
1554 	 * devices can't have any active URBs.
1555 	 */
1556 	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1557 	if (atomic_read(&urb->use_count) > 0) {
1558 		retval = 0;
1559 		usb_get_dev(urb->dev);
1560 	}
1561 	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1562 	if (retval == 0) {
1563 		hcd = bus_to_hcd(urb->dev->bus);
1564 		retval = unlink1(hcd, urb, status);
1565 		usb_put_dev(urb->dev);
1566 	}
1567 
1568 	if (retval == 0)
1569 		retval = -EINPROGRESS;
1570 	else if (retval != -EIDRM && retval != -EBUSY)
1571 		dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
1572 				urb, retval);
1573 	return retval;
1574 }
1575 
1576 /*-------------------------------------------------------------------------*/
1577 
1578 /**
1579  * usb_hcd_giveback_urb - return URB from HCD to device driver
1580  * @hcd: host controller returning the URB
1581  * @urb: urb being returned to the USB device driver.
1582  * @status: completion status code for the URB.
1583  * Context: in_interrupt()
1584  *
1585  * This hands the URB from HCD to its USB device driver, using its
1586  * completion function.  The HCD has freed all per-urb resources
1587  * (and is done using urb->hcpriv).  It also released all HCD locks;
1588  * the device driver won't cause problems if it frees, modifies,
1589  * or resubmits this URB.
1590  *
1591  * If @urb was unlinked, the value of @status will be overridden by
1592  * @urb->unlinked.  Erroneous short transfers are detected in case
1593  * the HCD hasn't checked for them.
1594  */
1595 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1596 {
1597 	urb->hcpriv = NULL;
1598 	if (unlikely(urb->unlinked))
1599 		status = urb->unlinked;
1600 	else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1601 			urb->actual_length < urb->transfer_buffer_length &&
1602 			!status))
1603 		status = -EREMOTEIO;
1604 
1605 	unmap_urb_for_dma(hcd, urb);
1606 	usbmon_urb_complete(&hcd->self, urb, status);
1607 	usb_unanchor_urb(urb);
1608 
1609 	/* pass ownership to the completion handler */
1610 	urb->status = status;
1611 	urb->complete (urb);
1612 	atomic_dec (&urb->use_count);
1613 	if (unlikely(atomic_read(&urb->reject)))
1614 		wake_up (&usb_kill_urb_queue);
1615 	usb_put_urb (urb);
1616 }
1617 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1618 
1619 /*-------------------------------------------------------------------------*/
1620 
1621 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1622  * queue to drain completely.  The caller must first insure that no more
1623  * URBs can be submitted for this endpoint.
1624  */
1625 void usb_hcd_flush_endpoint(struct usb_device *udev,
1626 		struct usb_host_endpoint *ep)
1627 {
1628 	struct usb_hcd		*hcd;
1629 	struct urb		*urb;
1630 
1631 	if (!ep)
1632 		return;
1633 	might_sleep();
1634 	hcd = bus_to_hcd(udev->bus);
1635 
1636 	/* No more submits can occur */
1637 	spin_lock_irq(&hcd_urb_list_lock);
1638 rescan:
1639 	list_for_each_entry (urb, &ep->urb_list, urb_list) {
1640 		int	is_in;
1641 
1642 		if (urb->unlinked)
1643 			continue;
1644 		usb_get_urb (urb);
1645 		is_in = usb_urb_dir_in(urb);
1646 		spin_unlock(&hcd_urb_list_lock);
1647 
1648 		/* kick hcd */
1649 		unlink1(hcd, urb, -ESHUTDOWN);
1650 		dev_dbg (hcd->self.controller,
1651 			"shutdown urb %p ep%d%s%s\n",
1652 			urb, usb_endpoint_num(&ep->desc),
1653 			is_in ? "in" : "out",
1654 			({	char *s;
1655 
1656 				 switch (usb_endpoint_type(&ep->desc)) {
1657 				 case USB_ENDPOINT_XFER_CONTROL:
1658 					s = ""; break;
1659 				 case USB_ENDPOINT_XFER_BULK:
1660 					s = "-bulk"; break;
1661 				 case USB_ENDPOINT_XFER_INT:
1662 					s = "-intr"; break;
1663 				 default:
1664 			 		s = "-iso"; break;
1665 				};
1666 				s;
1667 			}));
1668 		usb_put_urb (urb);
1669 
1670 		/* list contents may have changed */
1671 		spin_lock(&hcd_urb_list_lock);
1672 		goto rescan;
1673 	}
1674 	spin_unlock_irq(&hcd_urb_list_lock);
1675 
1676 	/* Wait until the endpoint queue is completely empty */
1677 	while (!list_empty (&ep->urb_list)) {
1678 		spin_lock_irq(&hcd_urb_list_lock);
1679 
1680 		/* The list may have changed while we acquired the spinlock */
1681 		urb = NULL;
1682 		if (!list_empty (&ep->urb_list)) {
1683 			urb = list_entry (ep->urb_list.prev, struct urb,
1684 					urb_list);
1685 			usb_get_urb (urb);
1686 		}
1687 		spin_unlock_irq(&hcd_urb_list_lock);
1688 
1689 		if (urb) {
1690 			usb_kill_urb (urb);
1691 			usb_put_urb (urb);
1692 		}
1693 	}
1694 }
1695 
1696 /**
1697  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1698  *				the bus bandwidth
1699  * @udev: target &usb_device
1700  * @new_config: new configuration to install
1701  * @cur_alt: the current alternate interface setting
1702  * @new_alt: alternate interface setting that is being installed
1703  *
1704  * To change configurations, pass in the new configuration in new_config,
1705  * and pass NULL for cur_alt and new_alt.
1706  *
1707  * To reset a device's configuration (put the device in the ADDRESSED state),
1708  * pass in NULL for new_config, cur_alt, and new_alt.
1709  *
1710  * To change alternate interface settings, pass in NULL for new_config,
1711  * pass in the current alternate interface setting in cur_alt,
1712  * and pass in the new alternate interface setting in new_alt.
1713  *
1714  * Returns an error if the requested bandwidth change exceeds the
1715  * bus bandwidth or host controller internal resources.
1716  */
1717 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1718 		struct usb_host_config *new_config,
1719 		struct usb_host_interface *cur_alt,
1720 		struct usb_host_interface *new_alt)
1721 {
1722 	int num_intfs, i, j;
1723 	struct usb_host_interface *alt = NULL;
1724 	int ret = 0;
1725 	struct usb_hcd *hcd;
1726 	struct usb_host_endpoint *ep;
1727 
1728 	hcd = bus_to_hcd(udev->bus);
1729 	if (!hcd->driver->check_bandwidth)
1730 		return 0;
1731 
1732 	/* Configuration is being removed - set configuration 0 */
1733 	if (!new_config && !cur_alt) {
1734 		for (i = 1; i < 16; ++i) {
1735 			ep = udev->ep_out[i];
1736 			if (ep)
1737 				hcd->driver->drop_endpoint(hcd, udev, ep);
1738 			ep = udev->ep_in[i];
1739 			if (ep)
1740 				hcd->driver->drop_endpoint(hcd, udev, ep);
1741 		}
1742 		hcd->driver->check_bandwidth(hcd, udev);
1743 		return 0;
1744 	}
1745 	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1746 	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1747 	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1748 	 * ok to exclude it.
1749 	 */
1750 	if (new_config) {
1751 		num_intfs = new_config->desc.bNumInterfaces;
1752 		/* Remove endpoints (except endpoint 0, which is always on the
1753 		 * schedule) from the old config from the schedule
1754 		 */
1755 		for (i = 1; i < 16; ++i) {
1756 			ep = udev->ep_out[i];
1757 			if (ep) {
1758 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1759 				if (ret < 0)
1760 					goto reset;
1761 			}
1762 			ep = udev->ep_in[i];
1763 			if (ep) {
1764 				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1765 				if (ret < 0)
1766 					goto reset;
1767 			}
1768 		}
1769 		for (i = 0; i < num_intfs; ++i) {
1770 			struct usb_host_interface *first_alt;
1771 			int iface_num;
1772 
1773 			first_alt = &new_config->intf_cache[i]->altsetting[0];
1774 			iface_num = first_alt->desc.bInterfaceNumber;
1775 			/* Set up endpoints for alternate interface setting 0 */
1776 			alt = usb_find_alt_setting(new_config, iface_num, 0);
1777 			if (!alt)
1778 				/* No alt setting 0? Pick the first setting. */
1779 				alt = first_alt;
1780 
1781 			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1782 				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1783 				if (ret < 0)
1784 					goto reset;
1785 			}
1786 		}
1787 	}
1788 	if (cur_alt && new_alt) {
1789 		struct usb_interface *iface = usb_ifnum_to_if(udev,
1790 				cur_alt->desc.bInterfaceNumber);
1791 
1792 		if (!iface)
1793 			return -EINVAL;
1794 		if (iface->resetting_device) {
1795 			/*
1796 			 * The USB core just reset the device, so the xHCI host
1797 			 * and the device will think alt setting 0 is installed.
1798 			 * However, the USB core will pass in the alternate
1799 			 * setting installed before the reset as cur_alt.  Dig
1800 			 * out the alternate setting 0 structure, or the first
1801 			 * alternate setting if a broken device doesn't have alt
1802 			 * setting 0.
1803 			 */
1804 			cur_alt = usb_altnum_to_altsetting(iface, 0);
1805 			if (!cur_alt)
1806 				cur_alt = &iface->altsetting[0];
1807 		}
1808 
1809 		/* Drop all the endpoints in the current alt setting */
1810 		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1811 			ret = hcd->driver->drop_endpoint(hcd, udev,
1812 					&cur_alt->endpoint[i]);
1813 			if (ret < 0)
1814 				goto reset;
1815 		}
1816 		/* Add all the endpoints in the new alt setting */
1817 		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1818 			ret = hcd->driver->add_endpoint(hcd, udev,
1819 					&new_alt->endpoint[i]);
1820 			if (ret < 0)
1821 				goto reset;
1822 		}
1823 	}
1824 	ret = hcd->driver->check_bandwidth(hcd, udev);
1825 reset:
1826 	if (ret < 0)
1827 		hcd->driver->reset_bandwidth(hcd, udev);
1828 	return ret;
1829 }
1830 
1831 /* Disables the endpoint: synchronizes with the hcd to make sure all
1832  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1833  * have been called previously.  Use for set_configuration, set_interface,
1834  * driver removal, physical disconnect.
1835  *
1836  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1837  * type, maxpacket size, toggle, halt status, and scheduling.
1838  */
1839 void usb_hcd_disable_endpoint(struct usb_device *udev,
1840 		struct usb_host_endpoint *ep)
1841 {
1842 	struct usb_hcd		*hcd;
1843 
1844 	might_sleep();
1845 	hcd = bus_to_hcd(udev->bus);
1846 	if (hcd->driver->endpoint_disable)
1847 		hcd->driver->endpoint_disable(hcd, ep);
1848 }
1849 
1850 /**
1851  * usb_hcd_reset_endpoint - reset host endpoint state
1852  * @udev: USB device.
1853  * @ep:   the endpoint to reset.
1854  *
1855  * Resets any host endpoint state such as the toggle bit, sequence
1856  * number and current window.
1857  */
1858 void usb_hcd_reset_endpoint(struct usb_device *udev,
1859 			    struct usb_host_endpoint *ep)
1860 {
1861 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1862 
1863 	if (hcd->driver->endpoint_reset)
1864 		hcd->driver->endpoint_reset(hcd, ep);
1865 	else {
1866 		int epnum = usb_endpoint_num(&ep->desc);
1867 		int is_out = usb_endpoint_dir_out(&ep->desc);
1868 		int is_control = usb_endpoint_xfer_control(&ep->desc);
1869 
1870 		usb_settoggle(udev, epnum, is_out, 0);
1871 		if (is_control)
1872 			usb_settoggle(udev, epnum, !is_out, 0);
1873 	}
1874 }
1875 
1876 /**
1877  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1878  * @interface:		alternate setting that includes all endpoints.
1879  * @eps:		array of endpoints that need streams.
1880  * @num_eps:		number of endpoints in the array.
1881  * @num_streams:	number of streams to allocate.
1882  * @mem_flags:		flags hcd should use to allocate memory.
1883  *
1884  * Sets up a group of bulk endpoints to have num_streams stream IDs available.
1885  * Drivers may queue multiple transfers to different stream IDs, which may
1886  * complete in a different order than they were queued.
1887  */
1888 int usb_alloc_streams(struct usb_interface *interface,
1889 		struct usb_host_endpoint **eps, unsigned int num_eps,
1890 		unsigned int num_streams, gfp_t mem_flags)
1891 {
1892 	struct usb_hcd *hcd;
1893 	struct usb_device *dev;
1894 	int i;
1895 
1896 	dev = interface_to_usbdev(interface);
1897 	hcd = bus_to_hcd(dev->bus);
1898 	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
1899 		return -EINVAL;
1900 	if (dev->speed != USB_SPEED_SUPER)
1901 		return -EINVAL;
1902 
1903 	/* Streams only apply to bulk endpoints. */
1904 	for (i = 0; i < num_eps; i++)
1905 		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
1906 			return -EINVAL;
1907 
1908 	return hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
1909 			num_streams, mem_flags);
1910 }
1911 EXPORT_SYMBOL_GPL(usb_alloc_streams);
1912 
1913 /**
1914  * usb_free_streams - free bulk endpoint stream IDs.
1915  * @interface:	alternate setting that includes all endpoints.
1916  * @eps:	array of endpoints to remove streams from.
1917  * @num_eps:	number of endpoints in the array.
1918  * @mem_flags:	flags hcd should use to allocate memory.
1919  *
1920  * Reverts a group of bulk endpoints back to not using stream IDs.
1921  * Can fail if we are given bad arguments, or HCD is broken.
1922  */
1923 void usb_free_streams(struct usb_interface *interface,
1924 		struct usb_host_endpoint **eps, unsigned int num_eps,
1925 		gfp_t mem_flags)
1926 {
1927 	struct usb_hcd *hcd;
1928 	struct usb_device *dev;
1929 	int i;
1930 
1931 	dev = interface_to_usbdev(interface);
1932 	hcd = bus_to_hcd(dev->bus);
1933 	if (dev->speed != USB_SPEED_SUPER)
1934 		return;
1935 
1936 	/* Streams only apply to bulk endpoints. */
1937 	for (i = 0; i < num_eps; i++)
1938 		if (!eps[i] || !usb_endpoint_xfer_bulk(&eps[i]->desc))
1939 			return;
1940 
1941 	hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
1942 }
1943 EXPORT_SYMBOL_GPL(usb_free_streams);
1944 
1945 /* Protect against drivers that try to unlink URBs after the device
1946  * is gone, by waiting until all unlinks for @udev are finished.
1947  * Since we don't currently track URBs by device, simply wait until
1948  * nothing is running in the locked region of usb_hcd_unlink_urb().
1949  */
1950 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
1951 {
1952 	spin_lock_irq(&hcd_urb_unlink_lock);
1953 	spin_unlock_irq(&hcd_urb_unlink_lock);
1954 }
1955 
1956 /*-------------------------------------------------------------------------*/
1957 
1958 /* called in any context */
1959 int usb_hcd_get_frame_number (struct usb_device *udev)
1960 {
1961 	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
1962 
1963 	if (!HCD_RH_RUNNING(hcd))
1964 		return -ESHUTDOWN;
1965 	return hcd->driver->get_frame_number (hcd);
1966 }
1967 
1968 /*-------------------------------------------------------------------------*/
1969 
1970 #ifdef	CONFIG_PM
1971 
1972 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
1973 {
1974 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
1975 	int		status;
1976 	int		old_state = hcd->state;
1977 
1978 	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
1979 			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
1980 			rhdev->do_remote_wakeup);
1981 	if (HCD_DEAD(hcd)) {
1982 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
1983 		return 0;
1984 	}
1985 
1986 	if (!hcd->driver->bus_suspend) {
1987 		status = -ENOENT;
1988 	} else {
1989 		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
1990 		hcd->state = HC_STATE_QUIESCING;
1991 		status = hcd->driver->bus_suspend(hcd);
1992 	}
1993 	if (status == 0) {
1994 		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
1995 		hcd->state = HC_STATE_SUSPENDED;
1996 
1997 		/* Did we race with a root-hub wakeup event? */
1998 		if (rhdev->do_remote_wakeup) {
1999 			char	buffer[6];
2000 
2001 			status = hcd->driver->hub_status_data(hcd, buffer);
2002 			if (status != 0) {
2003 				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2004 				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2005 				status = -EBUSY;
2006 			}
2007 		}
2008 	} else {
2009 		spin_lock_irq(&hcd_root_hub_lock);
2010 		if (!HCD_DEAD(hcd)) {
2011 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2012 			hcd->state = old_state;
2013 		}
2014 		spin_unlock_irq(&hcd_root_hub_lock);
2015 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2016 				"suspend", status);
2017 	}
2018 	return status;
2019 }
2020 
2021 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2022 {
2023 	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
2024 	int		status;
2025 	int		old_state = hcd->state;
2026 
2027 	dev_dbg(&rhdev->dev, "usb %sresume\n",
2028 			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2029 	if (HCD_DEAD(hcd)) {
2030 		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2031 		return 0;
2032 	}
2033 	if (!hcd->driver->bus_resume)
2034 		return -ENOENT;
2035 	if (HCD_RH_RUNNING(hcd))
2036 		return 0;
2037 
2038 	hcd->state = HC_STATE_RESUMING;
2039 	status = hcd->driver->bus_resume(hcd);
2040 	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2041 	if (status == 0) {
2042 		struct usb_device *udev;
2043 		int port1;
2044 
2045 		spin_lock_irq(&hcd_root_hub_lock);
2046 		if (!HCD_DEAD(hcd)) {
2047 			usb_set_device_state(rhdev, rhdev->actconfig
2048 					? USB_STATE_CONFIGURED
2049 					: USB_STATE_ADDRESS);
2050 			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2051 			hcd->state = HC_STATE_RUNNING;
2052 		}
2053 		spin_unlock_irq(&hcd_root_hub_lock);
2054 
2055 		/*
2056 		 * Check whether any of the enabled ports on the root hub are
2057 		 * unsuspended.  If they are then a TRSMRCY delay is needed
2058 		 * (this is what the USB-2 spec calls a "global resume").
2059 		 * Otherwise we can skip the delay.
2060 		 */
2061 		usb_hub_for_each_child(rhdev, port1, udev) {
2062 			if (udev->state != USB_STATE_NOTATTACHED &&
2063 					!udev->port_is_suspended) {
2064 				usleep_range(10000, 11000);	/* TRSMRCY */
2065 				break;
2066 			}
2067 		}
2068 	} else {
2069 		hcd->state = old_state;
2070 		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2071 				"resume", status);
2072 		if (status != -ESHUTDOWN)
2073 			usb_hc_died(hcd);
2074 	}
2075 	return status;
2076 }
2077 
2078 #endif	/* CONFIG_PM */
2079 
2080 #ifdef	CONFIG_USB_SUSPEND
2081 
2082 /* Workqueue routine for root-hub remote wakeup */
2083 static void hcd_resume_work(struct work_struct *work)
2084 {
2085 	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2086 	struct usb_device *udev = hcd->self.root_hub;
2087 
2088 	usb_lock_device(udev);
2089 	usb_remote_wakeup(udev);
2090 	usb_unlock_device(udev);
2091 }
2092 
2093 /**
2094  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2095  * @hcd: host controller for this root hub
2096  *
2097  * The USB host controller calls this function when its root hub is
2098  * suspended (with the remote wakeup feature enabled) and a remote
2099  * wakeup request is received.  The routine submits a workqueue request
2100  * to resume the root hub (that is, manage its downstream ports again).
2101  */
2102 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2103 {
2104 	unsigned long flags;
2105 
2106 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2107 	if (hcd->rh_registered) {
2108 		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2109 		queue_work(pm_wq, &hcd->wakeup_work);
2110 	}
2111 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2112 }
2113 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2114 
2115 #endif	/* CONFIG_USB_SUSPEND */
2116 
2117 /*-------------------------------------------------------------------------*/
2118 
2119 #ifdef	CONFIG_USB_OTG
2120 
2121 /**
2122  * usb_bus_start_enum - start immediate enumeration (for OTG)
2123  * @bus: the bus (must use hcd framework)
2124  * @port_num: 1-based number of port; usually bus->otg_port
2125  * Context: in_interrupt()
2126  *
2127  * Starts enumeration, with an immediate reset followed later by
2128  * khubd identifying and possibly configuring the device.
2129  * This is needed by OTG controller drivers, where it helps meet
2130  * HNP protocol timing requirements for starting a port reset.
2131  */
2132 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2133 {
2134 	struct usb_hcd		*hcd;
2135 	int			status = -EOPNOTSUPP;
2136 
2137 	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2138 	 * boards with root hubs hooked up to internal devices (instead of
2139 	 * just the OTG port) may need more attention to resetting...
2140 	 */
2141 	hcd = container_of (bus, struct usb_hcd, self);
2142 	if (port_num && hcd->driver->start_port_reset)
2143 		status = hcd->driver->start_port_reset(hcd, port_num);
2144 
2145 	/* run khubd shortly after (first) root port reset finishes;
2146 	 * it may issue others, until at least 50 msecs have passed.
2147 	 */
2148 	if (status == 0)
2149 		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2150 	return status;
2151 }
2152 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2153 
2154 #endif
2155 
2156 /*-------------------------------------------------------------------------*/
2157 
2158 /**
2159  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2160  * @irq: the IRQ being raised
2161  * @__hcd: pointer to the HCD whose IRQ is being signaled
2162  *
2163  * If the controller isn't HALTed, calls the driver's irq handler.
2164  * Checks whether the controller is now dead.
2165  */
2166 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2167 {
2168 	struct usb_hcd		*hcd = __hcd;
2169 	unsigned long		flags;
2170 	irqreturn_t		rc;
2171 
2172 	/* IRQF_DISABLED doesn't work correctly with shared IRQs
2173 	 * when the first handler doesn't use it.  So let's just
2174 	 * assume it's never used.
2175 	 */
2176 	local_irq_save(flags);
2177 
2178 	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2179 		rc = IRQ_NONE;
2180 	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2181 		rc = IRQ_NONE;
2182 	else
2183 		rc = IRQ_HANDLED;
2184 
2185 	local_irq_restore(flags);
2186 	return rc;
2187 }
2188 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2189 
2190 /*-------------------------------------------------------------------------*/
2191 
2192 /**
2193  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2194  * @hcd: pointer to the HCD representing the controller
2195  *
2196  * This is called by bus glue to report a USB host controller that died
2197  * while operations may still have been pending.  It's called automatically
2198  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2199  *
2200  * Only call this function with the primary HCD.
2201  */
2202 void usb_hc_died (struct usb_hcd *hcd)
2203 {
2204 	unsigned long flags;
2205 
2206 	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2207 
2208 	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2209 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2210 	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2211 	if (hcd->rh_registered) {
2212 		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2213 
2214 		/* make khubd clean up old urbs and devices */
2215 		usb_set_device_state (hcd->self.root_hub,
2216 				USB_STATE_NOTATTACHED);
2217 		usb_kick_khubd (hcd->self.root_hub);
2218 	}
2219 	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2220 		hcd = hcd->shared_hcd;
2221 		if (hcd->rh_registered) {
2222 			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2223 
2224 			/* make khubd clean up old urbs and devices */
2225 			usb_set_device_state(hcd->self.root_hub,
2226 					USB_STATE_NOTATTACHED);
2227 			usb_kick_khubd(hcd->self.root_hub);
2228 		}
2229 	}
2230 	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2231 	/* Make sure that the other roothub is also deallocated. */
2232 }
2233 EXPORT_SYMBOL_GPL (usb_hc_died);
2234 
2235 /*-------------------------------------------------------------------------*/
2236 
2237 /**
2238  * usb_create_shared_hcd - create and initialize an HCD structure
2239  * @driver: HC driver that will use this hcd
2240  * @dev: device for this HC, stored in hcd->self.controller
2241  * @bus_name: value to store in hcd->self.bus_name
2242  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2243  *              PCI device.  Only allocate certain resources for the primary HCD
2244  * Context: !in_interrupt()
2245  *
2246  * Allocate a struct usb_hcd, with extra space at the end for the
2247  * HC driver's private data.  Initialize the generic members of the
2248  * hcd structure.
2249  *
2250  * If memory is unavailable, returns NULL.
2251  */
2252 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2253 		struct device *dev, const char *bus_name,
2254 		struct usb_hcd *primary_hcd)
2255 {
2256 	struct usb_hcd *hcd;
2257 
2258 	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2259 	if (!hcd) {
2260 		dev_dbg (dev, "hcd alloc failed\n");
2261 		return NULL;
2262 	}
2263 	if (primary_hcd == NULL) {
2264 		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2265 				GFP_KERNEL);
2266 		if (!hcd->bandwidth_mutex) {
2267 			kfree(hcd);
2268 			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2269 			return NULL;
2270 		}
2271 		mutex_init(hcd->bandwidth_mutex);
2272 		dev_set_drvdata(dev, hcd);
2273 	} else {
2274 		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2275 		hcd->primary_hcd = primary_hcd;
2276 		primary_hcd->primary_hcd = primary_hcd;
2277 		hcd->shared_hcd = primary_hcd;
2278 		primary_hcd->shared_hcd = hcd;
2279 	}
2280 
2281 	kref_init(&hcd->kref);
2282 
2283 	usb_bus_init(&hcd->self);
2284 	hcd->self.controller = dev;
2285 	hcd->self.bus_name = bus_name;
2286 	hcd->self.uses_dma = (dev->dma_mask != NULL);
2287 
2288 	init_timer(&hcd->rh_timer);
2289 	hcd->rh_timer.function = rh_timer_func;
2290 	hcd->rh_timer.data = (unsigned long) hcd;
2291 #ifdef CONFIG_USB_SUSPEND
2292 	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2293 #endif
2294 
2295 	hcd->driver = driver;
2296 	hcd->speed = driver->flags & HCD_MASK;
2297 	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2298 			"USB Host Controller";
2299 	return hcd;
2300 }
2301 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2302 
2303 /**
2304  * usb_create_hcd - create and initialize an HCD structure
2305  * @driver: HC driver that will use this hcd
2306  * @dev: device for this HC, stored in hcd->self.controller
2307  * @bus_name: value to store in hcd->self.bus_name
2308  * Context: !in_interrupt()
2309  *
2310  * Allocate a struct usb_hcd, with extra space at the end for the
2311  * HC driver's private data.  Initialize the generic members of the
2312  * hcd structure.
2313  *
2314  * If memory is unavailable, returns NULL.
2315  */
2316 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2317 		struct device *dev, const char *bus_name)
2318 {
2319 	return usb_create_shared_hcd(driver, dev, bus_name, NULL);
2320 }
2321 EXPORT_SYMBOL_GPL(usb_create_hcd);
2322 
2323 /*
2324  * Roothubs that share one PCI device must also share the bandwidth mutex.
2325  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2326  * deallocated.
2327  *
2328  * Make sure to only deallocate the bandwidth_mutex when the primary HCD is
2329  * freed.  When hcd_release() is called for the non-primary HCD, set the
2330  * primary_hcd's shared_hcd pointer to null (since the non-primary HCD will be
2331  * freed shortly).
2332  */
2333 static void hcd_release (struct kref *kref)
2334 {
2335 	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2336 
2337 	if (usb_hcd_is_primary_hcd(hcd))
2338 		kfree(hcd->bandwidth_mutex);
2339 	else
2340 		hcd->shared_hcd->shared_hcd = NULL;
2341 	kfree(hcd);
2342 }
2343 
2344 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2345 {
2346 	if (hcd)
2347 		kref_get (&hcd->kref);
2348 	return hcd;
2349 }
2350 EXPORT_SYMBOL_GPL(usb_get_hcd);
2351 
2352 void usb_put_hcd (struct usb_hcd *hcd)
2353 {
2354 	if (hcd)
2355 		kref_put (&hcd->kref, hcd_release);
2356 }
2357 EXPORT_SYMBOL_GPL(usb_put_hcd);
2358 
2359 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2360 {
2361 	if (!hcd->primary_hcd)
2362 		return 1;
2363 	return hcd == hcd->primary_hcd;
2364 }
2365 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2366 
2367 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2368 		unsigned int irqnum, unsigned long irqflags)
2369 {
2370 	int retval;
2371 
2372 	if (hcd->driver->irq) {
2373 
2374 		/* IRQF_DISABLED doesn't work as advertised when used together
2375 		 * with IRQF_SHARED. As usb_hcd_irq() will always disable
2376 		 * interrupts we can remove it here.
2377 		 */
2378 		if (irqflags & IRQF_SHARED)
2379 			irqflags &= ~IRQF_DISABLED;
2380 
2381 		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2382 				hcd->driver->description, hcd->self.busnum);
2383 		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2384 				hcd->irq_descr, hcd);
2385 		if (retval != 0) {
2386 			dev_err(hcd->self.controller,
2387 					"request interrupt %d failed\n",
2388 					irqnum);
2389 			return retval;
2390 		}
2391 		hcd->irq = irqnum;
2392 		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2393 				(hcd->driver->flags & HCD_MEMORY) ?
2394 					"io mem" : "io base",
2395 					(unsigned long long)hcd->rsrc_start);
2396 	} else {
2397 		hcd->irq = 0;
2398 		if (hcd->rsrc_start)
2399 			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2400 					(hcd->driver->flags & HCD_MEMORY) ?
2401 					"io mem" : "io base",
2402 					(unsigned long long)hcd->rsrc_start);
2403 	}
2404 	return 0;
2405 }
2406 
2407 /**
2408  * usb_add_hcd - finish generic HCD structure initialization and register
2409  * @hcd: the usb_hcd structure to initialize
2410  * @irqnum: Interrupt line to allocate
2411  * @irqflags: Interrupt type flags
2412  *
2413  * Finish the remaining parts of generic HCD initialization: allocate the
2414  * buffers of consistent memory, register the bus, request the IRQ line,
2415  * and call the driver's reset() and start() routines.
2416  */
2417 int usb_add_hcd(struct usb_hcd *hcd,
2418 		unsigned int irqnum, unsigned long irqflags)
2419 {
2420 	int retval;
2421 	struct usb_device *rhdev;
2422 
2423 	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2424 
2425 	/* Keep old behaviour if authorized_default is not in [0, 1]. */
2426 	if (authorized_default < 0 || authorized_default > 1)
2427 		hcd->authorized_default = hcd->wireless? 0 : 1;
2428 	else
2429 		hcd->authorized_default = authorized_default;
2430 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2431 
2432 	/* HC is in reset state, but accessible.  Now do the one-time init,
2433 	 * bottom up so that hcds can customize the root hubs before khubd
2434 	 * starts talking to them.  (Note, bus id is assigned early too.)
2435 	 */
2436 	if ((retval = hcd_buffer_create(hcd)) != 0) {
2437 		dev_dbg(hcd->self.controller, "pool alloc failed\n");
2438 		return retval;
2439 	}
2440 
2441 	if ((retval = usb_register_bus(&hcd->self)) < 0)
2442 		goto err_register_bus;
2443 
2444 	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
2445 		dev_err(hcd->self.controller, "unable to allocate root hub\n");
2446 		retval = -ENOMEM;
2447 		goto err_allocate_root_hub;
2448 	}
2449 	hcd->self.root_hub = rhdev;
2450 
2451 	switch (hcd->speed) {
2452 	case HCD_USB11:
2453 		rhdev->speed = USB_SPEED_FULL;
2454 		break;
2455 	case HCD_USB2:
2456 		rhdev->speed = USB_SPEED_HIGH;
2457 		break;
2458 	case HCD_USB3:
2459 		rhdev->speed = USB_SPEED_SUPER;
2460 		break;
2461 	default:
2462 		retval = -EINVAL;
2463 		goto err_set_rh_speed;
2464 	}
2465 
2466 	/* wakeup flag init defaults to "everything works" for root hubs,
2467 	 * but drivers can override it in reset() if needed, along with
2468 	 * recording the overall controller's system wakeup capability.
2469 	 */
2470 	device_set_wakeup_capable(&rhdev->dev, 1);
2471 
2472 	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2473 	 * registered.  But since the controller can die at any time,
2474 	 * let's initialize the flag before touching the hardware.
2475 	 */
2476 	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2477 
2478 	/* "reset" is misnamed; its role is now one-time init. the controller
2479 	 * should already have been reset (and boot firmware kicked off etc).
2480 	 */
2481 	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
2482 		dev_err(hcd->self.controller, "can't setup\n");
2483 		goto err_hcd_driver_setup;
2484 	}
2485 	hcd->rh_pollable = 1;
2486 
2487 	/* NOTE: root hub and controller capabilities may not be the same */
2488 	if (device_can_wakeup(hcd->self.controller)
2489 			&& device_can_wakeup(&hcd->self.root_hub->dev))
2490 		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2491 
2492 	/* enable irqs just before we start the controller,
2493 	 * if the BIOS provides legacy PCI irqs.
2494 	 */
2495 	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2496 		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2497 		if (retval)
2498 			goto err_request_irq;
2499 	}
2500 
2501 	hcd->state = HC_STATE_RUNNING;
2502 	retval = hcd->driver->start(hcd);
2503 	if (retval < 0) {
2504 		dev_err(hcd->self.controller, "startup error %d\n", retval);
2505 		goto err_hcd_driver_start;
2506 	}
2507 
2508 	/* starting here, usbcore will pay attention to this root hub */
2509 	rhdev->bus_mA = min(500u, hcd->power_budget);
2510 	if ((retval = register_root_hub(hcd)) != 0)
2511 		goto err_register_root_hub;
2512 
2513 	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2514 	if (retval < 0) {
2515 		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2516 		       retval);
2517 		goto error_create_attr_group;
2518 	}
2519 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2520 		usb_hcd_poll_rh_status(hcd);
2521 
2522 	/*
2523 	 * Host controllers don't generate their own wakeup requests;
2524 	 * they only forward requests from the root hub.  Therefore
2525 	 * controllers should always be enabled for remote wakeup.
2526 	 */
2527 	device_wakeup_enable(hcd->self.controller);
2528 	return retval;
2529 
2530 error_create_attr_group:
2531 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2532 	if (HC_IS_RUNNING(hcd->state))
2533 		hcd->state = HC_STATE_QUIESCING;
2534 	spin_lock_irq(&hcd_root_hub_lock);
2535 	hcd->rh_registered = 0;
2536 	spin_unlock_irq(&hcd_root_hub_lock);
2537 
2538 #ifdef CONFIG_USB_SUSPEND
2539 	cancel_work_sync(&hcd->wakeup_work);
2540 #endif
2541 	mutex_lock(&usb_bus_list_lock);
2542 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2543 	mutex_unlock(&usb_bus_list_lock);
2544 err_register_root_hub:
2545 	hcd->rh_pollable = 0;
2546 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2547 	del_timer_sync(&hcd->rh_timer);
2548 	hcd->driver->stop(hcd);
2549 	hcd->state = HC_STATE_HALT;
2550 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2551 	del_timer_sync(&hcd->rh_timer);
2552 err_hcd_driver_start:
2553 	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2554 		free_irq(irqnum, hcd);
2555 err_request_irq:
2556 err_hcd_driver_setup:
2557 err_set_rh_speed:
2558 	usb_put_dev(hcd->self.root_hub);
2559 err_allocate_root_hub:
2560 	usb_deregister_bus(&hcd->self);
2561 err_register_bus:
2562 	hcd_buffer_destroy(hcd);
2563 	return retval;
2564 }
2565 EXPORT_SYMBOL_GPL(usb_add_hcd);
2566 
2567 /**
2568  * usb_remove_hcd - shutdown processing for generic HCDs
2569  * @hcd: the usb_hcd structure to remove
2570  * Context: !in_interrupt()
2571  *
2572  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2573  * invoking the HCD's stop() method.
2574  */
2575 void usb_remove_hcd(struct usb_hcd *hcd)
2576 {
2577 	struct usb_device *rhdev = hcd->self.root_hub;
2578 
2579 	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2580 
2581 	usb_get_dev(rhdev);
2582 	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2583 
2584 	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2585 	if (HC_IS_RUNNING (hcd->state))
2586 		hcd->state = HC_STATE_QUIESCING;
2587 
2588 	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2589 	spin_lock_irq (&hcd_root_hub_lock);
2590 	hcd->rh_registered = 0;
2591 	spin_unlock_irq (&hcd_root_hub_lock);
2592 
2593 #ifdef CONFIG_USB_SUSPEND
2594 	cancel_work_sync(&hcd->wakeup_work);
2595 #endif
2596 
2597 	mutex_lock(&usb_bus_list_lock);
2598 	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2599 	mutex_unlock(&usb_bus_list_lock);
2600 
2601 	/* Prevent any more root-hub status calls from the timer.
2602 	 * The HCD might still restart the timer (if a port status change
2603 	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2604 	 * the hub_status_data() callback.
2605 	 */
2606 	hcd->rh_pollable = 0;
2607 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2608 	del_timer_sync(&hcd->rh_timer);
2609 
2610 	hcd->driver->stop(hcd);
2611 	hcd->state = HC_STATE_HALT;
2612 
2613 	/* In case the HCD restarted the timer, stop it again. */
2614 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2615 	del_timer_sync(&hcd->rh_timer);
2616 
2617 	if (usb_hcd_is_primary_hcd(hcd)) {
2618 		if (hcd->irq > 0)
2619 			free_irq(hcd->irq, hcd);
2620 	}
2621 
2622 	usb_put_dev(hcd->self.root_hub);
2623 	usb_deregister_bus(&hcd->self);
2624 	hcd_buffer_destroy(hcd);
2625 }
2626 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2627 
2628 void
2629 usb_hcd_platform_shutdown(struct platform_device* dev)
2630 {
2631 	struct usb_hcd *hcd = platform_get_drvdata(dev);
2632 
2633 	if (hcd->driver->shutdown)
2634 		hcd->driver->shutdown(hcd);
2635 }
2636 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2637 
2638 /*-------------------------------------------------------------------------*/
2639 
2640 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2641 
2642 struct usb_mon_operations *mon_ops;
2643 
2644 /*
2645  * The registration is unlocked.
2646  * We do it this way because we do not want to lock in hot paths.
2647  *
2648  * Notice that the code is minimally error-proof. Because usbmon needs
2649  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2650  */
2651 
2652 int usb_mon_register (struct usb_mon_operations *ops)
2653 {
2654 
2655 	if (mon_ops)
2656 		return -EBUSY;
2657 
2658 	mon_ops = ops;
2659 	mb();
2660 	return 0;
2661 }
2662 EXPORT_SYMBOL_GPL (usb_mon_register);
2663 
2664 void usb_mon_deregister (void)
2665 {
2666 
2667 	if (mon_ops == NULL) {
2668 		printk(KERN_ERR "USB: monitor was not registered\n");
2669 		return;
2670 	}
2671 	mon_ops = NULL;
2672 	mb();
2673 }
2674 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2675 
2676 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2677