1 /*
2 * (C) Copyright Linus Torvalds 1999
3 * (C) Copyright Johannes Erdfelt 1999-2001
4 * (C) Copyright Andreas Gal 1999
5 * (C) Copyright Gregory P. Smith 1999
6 * (C) Copyright Deti Fliegl 1999
7 * (C) Copyright Randy Dunlap 2000
8 * (C) Copyright David Brownell 2000-2002
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
17 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 * for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 #include <linux/bcd.h>
26 #include <linux/module.h>
27 #include <linux/version.h>
28 #include <linux/kernel.h>
29 #include <linux/slab.h>
30 #include <linux/completion.h>
31 #include <linux/utsname.h>
32 #include <linux/mm.h>
33 #include <asm/io.h>
34 #include <linux/device.h>
35 #include <linux/dma-mapping.h>
36 #include <linux/mutex.h>
37 #include <asm/irq.h>
38 #include <asm/byteorder.h>
39 #include <asm/unaligned.h>
40 #include <linux/platform_device.h>
41 #include <linux/workqueue.h>
42 #include <linux/pm_runtime.h>
43 #include <linux/types.h>
44
45 #include <linux/phy/phy.h>
46 #include <linux/usb.h>
47 #include <linux/usb/hcd.h>
48 #include <linux/usb/phy.h>
49
50 #include "usb.h"
51
52
53 /*-------------------------------------------------------------------------*/
54
55 /*
56 * USB Host Controller Driver framework
57 *
58 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
59 * HCD-specific behaviors/bugs.
60 *
61 * This does error checks, tracks devices and urbs, and delegates to a
62 * "hc_driver" only for code (and data) that really needs to know about
63 * hardware differences. That includes root hub registers, i/o queues,
64 * and so on ... but as little else as possible.
65 *
66 * Shared code includes most of the "root hub" code (these are emulated,
67 * though each HC's hardware works differently) and PCI glue, plus request
68 * tracking overhead. The HCD code should only block on spinlocks or on
69 * hardware handshaking; blocking on software events (such as other kernel
70 * threads releasing resources, or completing actions) is all generic.
71 *
72 * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
73 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
74 * only by the hub driver ... and that neither should be seen or used by
75 * usb client device drivers.
76 *
77 * Contributors of ideas or unattributed patches include: David Brownell,
78 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
79 *
80 * HISTORY:
81 * 2002-02-21 Pull in most of the usb_bus support from usb.c; some
82 * associated cleanup. "usb_hcd" still != "usb_bus".
83 * 2001-12-12 Initial patch version for Linux 2.5.1 kernel.
84 */
85
86 /*-------------------------------------------------------------------------*/
87
88 /* Keep track of which host controller drivers are loaded */
89 unsigned long usb_hcds_loaded;
90 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
91
92 /* host controllers we manage */
93 LIST_HEAD (usb_bus_list);
94 EXPORT_SYMBOL_GPL (usb_bus_list);
95
96 /* used when allocating bus numbers */
97 #define USB_MAXBUS 64
98 static DECLARE_BITMAP(busmap, USB_MAXBUS);
99
100 /* used when updating list of hcds */
101 DEFINE_MUTEX(usb_bus_list_lock); /* exported only for usbfs */
102 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
103
104 /* used for controlling access to virtual root hubs */
105 static DEFINE_SPINLOCK(hcd_root_hub_lock);
106
107 /* used when updating an endpoint's URB list */
108 static DEFINE_SPINLOCK(hcd_urb_list_lock);
109
110 /* used to protect against unlinking URBs after the device is gone */
111 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
112
113 /* wait queue for synchronous unlinks */
114 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
115
is_root_hub(struct usb_device * udev)116 static inline int is_root_hub(struct usb_device *udev)
117 {
118 return (udev->parent == NULL);
119 }
120
121 /*-------------------------------------------------------------------------*/
122
123 /*
124 * Sharable chunks of root hub code.
125 */
126
127 /*-------------------------------------------------------------------------*/
128 #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
129 #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
130
131 /* usb 3.0 root hub device descriptor */
132 static const u8 usb3_rh_dev_descriptor[18] = {
133 0x12, /* __u8 bLength; */
134 0x01, /* __u8 bDescriptorType; Device */
135 0x00, 0x03, /* __le16 bcdUSB; v3.0 */
136
137 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
138 0x00, /* __u8 bDeviceSubClass; */
139 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */
140 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */
141
142 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */
143 0x03, 0x00, /* __le16 idProduct; device 0x0003 */
144 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
145
146 0x03, /* __u8 iManufacturer; */
147 0x02, /* __u8 iProduct; */
148 0x01, /* __u8 iSerialNumber; */
149 0x01 /* __u8 bNumConfigurations; */
150 };
151
152 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
153 static const u8 usb25_rh_dev_descriptor[18] = {
154 0x12, /* __u8 bLength; */
155 0x01, /* __u8 bDescriptorType; Device */
156 0x50, 0x02, /* __le16 bcdUSB; v2.5 */
157
158 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
159 0x00, /* __u8 bDeviceSubClass; */
160 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */
161 0xFF, /* __u8 bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
162
163 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */
164 0x02, 0x00, /* __le16 idProduct; device 0x0002 */
165 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
166
167 0x03, /* __u8 iManufacturer; */
168 0x02, /* __u8 iProduct; */
169 0x01, /* __u8 iSerialNumber; */
170 0x01 /* __u8 bNumConfigurations; */
171 };
172
173 /* usb 2.0 root hub device descriptor */
174 static const u8 usb2_rh_dev_descriptor[18] = {
175 0x12, /* __u8 bLength; */
176 0x01, /* __u8 bDescriptorType; Device */
177 0x00, 0x02, /* __le16 bcdUSB; v2.0 */
178
179 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
180 0x00, /* __u8 bDeviceSubClass; */
181 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */
182 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
183
184 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */
185 0x02, 0x00, /* __le16 idProduct; device 0x0002 */
186 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
187
188 0x03, /* __u8 iManufacturer; */
189 0x02, /* __u8 iProduct; */
190 0x01, /* __u8 iSerialNumber; */
191 0x01 /* __u8 bNumConfigurations; */
192 };
193
194 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
195
196 /* usb 1.1 root hub device descriptor */
197 static const u8 usb11_rh_dev_descriptor[18] = {
198 0x12, /* __u8 bLength; */
199 0x01, /* __u8 bDescriptorType; Device */
200 0x10, 0x01, /* __le16 bcdUSB; v1.1 */
201
202 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
203 0x00, /* __u8 bDeviceSubClass; */
204 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */
205 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
206
207 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */
208 0x01, 0x00, /* __le16 idProduct; device 0x0001 */
209 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
210
211 0x03, /* __u8 iManufacturer; */
212 0x02, /* __u8 iProduct; */
213 0x01, /* __u8 iSerialNumber; */
214 0x01 /* __u8 bNumConfigurations; */
215 };
216
217
218 /*-------------------------------------------------------------------------*/
219
220 /* Configuration descriptors for our root hubs */
221
222 static const u8 fs_rh_config_descriptor[] = {
223
224 /* one configuration */
225 0x09, /* __u8 bLength; */
226 0x02, /* __u8 bDescriptorType; Configuration */
227 0x19, 0x00, /* __le16 wTotalLength; */
228 0x01, /* __u8 bNumInterfaces; (1) */
229 0x01, /* __u8 bConfigurationValue; */
230 0x00, /* __u8 iConfiguration; */
231 0xc0, /* __u8 bmAttributes;
232 Bit 7: must be set,
233 6: Self-powered,
234 5: Remote wakeup,
235 4..0: resvd */
236 0x00, /* __u8 MaxPower; */
237
238 /* USB 1.1:
239 * USB 2.0, single TT organization (mandatory):
240 * one interface, protocol 0
241 *
242 * USB 2.0, multiple TT organization (optional):
243 * two interfaces, protocols 1 (like single TT)
244 * and 2 (multiple TT mode) ... config is
245 * sometimes settable
246 * NOT IMPLEMENTED
247 */
248
249 /* one interface */
250 0x09, /* __u8 if_bLength; */
251 0x04, /* __u8 if_bDescriptorType; Interface */
252 0x00, /* __u8 if_bInterfaceNumber; */
253 0x00, /* __u8 if_bAlternateSetting; */
254 0x01, /* __u8 if_bNumEndpoints; */
255 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
256 0x00, /* __u8 if_bInterfaceSubClass; */
257 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
258 0x00, /* __u8 if_iInterface; */
259
260 /* one endpoint (status change endpoint) */
261 0x07, /* __u8 ep_bLength; */
262 0x05, /* __u8 ep_bDescriptorType; Endpoint */
263 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
264 0x03, /* __u8 ep_bmAttributes; Interrupt */
265 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
266 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */
267 };
268
269 static const u8 hs_rh_config_descriptor[] = {
270
271 /* one configuration */
272 0x09, /* __u8 bLength; */
273 0x02, /* __u8 bDescriptorType; Configuration */
274 0x19, 0x00, /* __le16 wTotalLength; */
275 0x01, /* __u8 bNumInterfaces; (1) */
276 0x01, /* __u8 bConfigurationValue; */
277 0x00, /* __u8 iConfiguration; */
278 0xc0, /* __u8 bmAttributes;
279 Bit 7: must be set,
280 6: Self-powered,
281 5: Remote wakeup,
282 4..0: resvd */
283 0x00, /* __u8 MaxPower; */
284
285 /* USB 1.1:
286 * USB 2.0, single TT organization (mandatory):
287 * one interface, protocol 0
288 *
289 * USB 2.0, multiple TT organization (optional):
290 * two interfaces, protocols 1 (like single TT)
291 * and 2 (multiple TT mode) ... config is
292 * sometimes settable
293 * NOT IMPLEMENTED
294 */
295
296 /* one interface */
297 0x09, /* __u8 if_bLength; */
298 0x04, /* __u8 if_bDescriptorType; Interface */
299 0x00, /* __u8 if_bInterfaceNumber; */
300 0x00, /* __u8 if_bAlternateSetting; */
301 0x01, /* __u8 if_bNumEndpoints; */
302 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
303 0x00, /* __u8 if_bInterfaceSubClass; */
304 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
305 0x00, /* __u8 if_iInterface; */
306
307 /* one endpoint (status change endpoint) */
308 0x07, /* __u8 ep_bLength; */
309 0x05, /* __u8 ep_bDescriptorType; Endpoint */
310 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
311 0x03, /* __u8 ep_bmAttributes; Interrupt */
312 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
313 * see hub.c:hub_configure() for details. */
314 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
315 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */
316 };
317
318 static const u8 ss_rh_config_descriptor[] = {
319 /* one configuration */
320 0x09, /* __u8 bLength; */
321 0x02, /* __u8 bDescriptorType; Configuration */
322 0x1f, 0x00, /* __le16 wTotalLength; */
323 0x01, /* __u8 bNumInterfaces; (1) */
324 0x01, /* __u8 bConfigurationValue; */
325 0x00, /* __u8 iConfiguration; */
326 0xc0, /* __u8 bmAttributes;
327 Bit 7: must be set,
328 6: Self-powered,
329 5: Remote wakeup,
330 4..0: resvd */
331 0x00, /* __u8 MaxPower; */
332
333 /* one interface */
334 0x09, /* __u8 if_bLength; */
335 0x04, /* __u8 if_bDescriptorType; Interface */
336 0x00, /* __u8 if_bInterfaceNumber; */
337 0x00, /* __u8 if_bAlternateSetting; */
338 0x01, /* __u8 if_bNumEndpoints; */
339 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
340 0x00, /* __u8 if_bInterfaceSubClass; */
341 0x00, /* __u8 if_bInterfaceProtocol; */
342 0x00, /* __u8 if_iInterface; */
343
344 /* one endpoint (status change endpoint) */
345 0x07, /* __u8 ep_bLength; */
346 0x05, /* __u8 ep_bDescriptorType; Endpoint */
347 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
348 0x03, /* __u8 ep_bmAttributes; Interrupt */
349 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
350 * see hub.c:hub_configure() for details. */
351 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
352 0x0c, /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */
353
354 /* one SuperSpeed endpoint companion descriptor */
355 0x06, /* __u8 ss_bLength */
356 0x30, /* __u8 ss_bDescriptorType; SuperSpeed EP Companion */
357 0x00, /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
358 0x00, /* __u8 ss_bmAttributes; 1 packet per service interval */
359 0x02, 0x00 /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
360 };
361
362 /* authorized_default behaviour:
363 * -1 is authorized for all devices except wireless (old behaviour)
364 * 0 is unauthorized for all devices
365 * 1 is authorized for all devices
366 */
367 static int authorized_default = -1;
368 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
369 MODULE_PARM_DESC(authorized_default,
370 "Default USB device authorization: 0 is not authorized, 1 is "
371 "authorized, -1 is authorized except for wireless USB (default, "
372 "old behaviour");
373 /*-------------------------------------------------------------------------*/
374
375 /**
376 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
377 * @s: Null-terminated ASCII (actually ISO-8859-1) string
378 * @buf: Buffer for USB string descriptor (header + UTF-16LE)
379 * @len: Length (in bytes; may be odd) of descriptor buffer.
380 *
381 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
382 * whichever is less.
383 *
384 * Note:
385 * USB String descriptors can contain at most 126 characters; input
386 * strings longer than that are truncated.
387 */
388 static unsigned
ascii2desc(char const * s,u8 * buf,unsigned len)389 ascii2desc(char const *s, u8 *buf, unsigned len)
390 {
391 unsigned n, t = 2 + 2*strlen(s);
392
393 if (t > 254)
394 t = 254; /* Longest possible UTF string descriptor */
395 if (len > t)
396 len = t;
397
398 t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */
399
400 n = len;
401 while (n--) {
402 *buf++ = t;
403 if (!n--)
404 break;
405 *buf++ = t >> 8;
406 t = (unsigned char)*s++;
407 }
408 return len;
409 }
410
411 /**
412 * rh_string() - provides string descriptors for root hub
413 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
414 * @hcd: the host controller for this root hub
415 * @data: buffer for output packet
416 * @len: length of the provided buffer
417 *
418 * Produces either a manufacturer, product or serial number string for the
419 * virtual root hub device.
420 *
421 * Return: The number of bytes filled in: the length of the descriptor or
422 * of the provided buffer, whichever is less.
423 */
424 static unsigned
rh_string(int id,struct usb_hcd const * hcd,u8 * data,unsigned len)425 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
426 {
427 char buf[100];
428 char const *s;
429 static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
430
431 /* language ids */
432 switch (id) {
433 case 0:
434 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
435 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
436 if (len > 4)
437 len = 4;
438 memcpy(data, langids, len);
439 return len;
440 case 1:
441 /* Serial number */
442 s = hcd->self.bus_name;
443 break;
444 case 2:
445 /* Product name */
446 s = hcd->product_desc;
447 break;
448 case 3:
449 /* Manufacturer */
450 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
451 init_utsname()->release, hcd->driver->description);
452 s = buf;
453 break;
454 default:
455 /* Can't happen; caller guarantees it */
456 return 0;
457 }
458
459 return ascii2desc(s, data, len);
460 }
461
462
463 /* Root hub control transfers execute synchronously */
rh_call_control(struct usb_hcd * hcd,struct urb * urb)464 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
465 {
466 struct usb_ctrlrequest *cmd;
467 u16 typeReq, wValue, wIndex, wLength;
468 u8 *ubuf = urb->transfer_buffer;
469 unsigned len = 0;
470 int status;
471 u8 patch_wakeup = 0;
472 u8 patch_protocol = 0;
473 u16 tbuf_size;
474 u8 *tbuf = NULL;
475 const u8 *bufp;
476
477 might_sleep();
478
479 spin_lock_irq(&hcd_root_hub_lock);
480 status = usb_hcd_link_urb_to_ep(hcd, urb);
481 spin_unlock_irq(&hcd_root_hub_lock);
482 if (status)
483 return status;
484 urb->hcpriv = hcd; /* Indicate it's queued */
485
486 cmd = (struct usb_ctrlrequest *) urb->setup_packet;
487 typeReq = (cmd->bRequestType << 8) | cmd->bRequest;
488 wValue = le16_to_cpu (cmd->wValue);
489 wIndex = le16_to_cpu (cmd->wIndex);
490 wLength = le16_to_cpu (cmd->wLength);
491
492 if (wLength > urb->transfer_buffer_length)
493 goto error;
494
495 /*
496 * tbuf should be at least as big as the
497 * USB hub descriptor.
498 */
499 tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
500 tbuf = kzalloc(tbuf_size, GFP_KERNEL);
501 if (!tbuf) {
502 status = -ENOMEM;
503 goto err_alloc;
504 }
505
506 bufp = tbuf;
507
508
509 urb->actual_length = 0;
510 switch (typeReq) {
511
512 /* DEVICE REQUESTS */
513
514 /* The root hub's remote wakeup enable bit is implemented using
515 * driver model wakeup flags. If this system supports wakeup
516 * through USB, userspace may change the default "allow wakeup"
517 * policy through sysfs or these calls.
518 *
519 * Most root hubs support wakeup from downstream devices, for
520 * runtime power management (disabling USB clocks and reducing
521 * VBUS power usage). However, not all of them do so; silicon,
522 * board, and BIOS bugs here are not uncommon, so these can't
523 * be treated quite like external hubs.
524 *
525 * Likewise, not all root hubs will pass wakeup events upstream,
526 * to wake up the whole system. So don't assume root hub and
527 * controller capabilities are identical.
528 */
529
530 case DeviceRequest | USB_REQ_GET_STATUS:
531 tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
532 << USB_DEVICE_REMOTE_WAKEUP)
533 | (1 << USB_DEVICE_SELF_POWERED);
534 tbuf[1] = 0;
535 len = 2;
536 break;
537 case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
538 if (wValue == USB_DEVICE_REMOTE_WAKEUP)
539 device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
540 else
541 goto error;
542 break;
543 case DeviceOutRequest | USB_REQ_SET_FEATURE:
544 if (device_can_wakeup(&hcd->self.root_hub->dev)
545 && wValue == USB_DEVICE_REMOTE_WAKEUP)
546 device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
547 else
548 goto error;
549 break;
550 case DeviceRequest | USB_REQ_GET_CONFIGURATION:
551 tbuf[0] = 1;
552 len = 1;
553 /* FALLTHROUGH */
554 case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
555 break;
556 case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
557 switch (wValue & 0xff00) {
558 case USB_DT_DEVICE << 8:
559 switch (hcd->speed) {
560 case HCD_USB3:
561 bufp = usb3_rh_dev_descriptor;
562 break;
563 case HCD_USB25:
564 bufp = usb25_rh_dev_descriptor;
565 break;
566 case HCD_USB2:
567 bufp = usb2_rh_dev_descriptor;
568 break;
569 case HCD_USB11:
570 bufp = usb11_rh_dev_descriptor;
571 break;
572 default:
573 goto error;
574 }
575 len = 18;
576 if (hcd->has_tt)
577 patch_protocol = 1;
578 break;
579 case USB_DT_CONFIG << 8:
580 switch (hcd->speed) {
581 case HCD_USB3:
582 bufp = ss_rh_config_descriptor;
583 len = sizeof ss_rh_config_descriptor;
584 break;
585 case HCD_USB25:
586 case HCD_USB2:
587 bufp = hs_rh_config_descriptor;
588 len = sizeof hs_rh_config_descriptor;
589 break;
590 case HCD_USB11:
591 bufp = fs_rh_config_descriptor;
592 len = sizeof fs_rh_config_descriptor;
593 break;
594 default:
595 goto error;
596 }
597 if (device_can_wakeup(&hcd->self.root_hub->dev))
598 patch_wakeup = 1;
599 break;
600 case USB_DT_STRING << 8:
601 if ((wValue & 0xff) < 4)
602 urb->actual_length = rh_string(wValue & 0xff,
603 hcd, ubuf, wLength);
604 else /* unsupported IDs --> "protocol stall" */
605 goto error;
606 break;
607 case USB_DT_BOS << 8:
608 goto nongeneric;
609 default:
610 goto error;
611 }
612 break;
613 case DeviceRequest | USB_REQ_GET_INTERFACE:
614 tbuf[0] = 0;
615 len = 1;
616 /* FALLTHROUGH */
617 case DeviceOutRequest | USB_REQ_SET_INTERFACE:
618 break;
619 case DeviceOutRequest | USB_REQ_SET_ADDRESS:
620 /* wValue == urb->dev->devaddr */
621 dev_dbg (hcd->self.controller, "root hub device address %d\n",
622 wValue);
623 break;
624
625 /* INTERFACE REQUESTS (no defined feature/status flags) */
626
627 /* ENDPOINT REQUESTS */
628
629 case EndpointRequest | USB_REQ_GET_STATUS:
630 /* ENDPOINT_HALT flag */
631 tbuf[0] = 0;
632 tbuf[1] = 0;
633 len = 2;
634 /* FALLTHROUGH */
635 case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
636 case EndpointOutRequest | USB_REQ_SET_FEATURE:
637 dev_dbg (hcd->self.controller, "no endpoint features yet\n");
638 break;
639
640 /* CLASS REQUESTS (and errors) */
641
642 default:
643 nongeneric:
644 /* non-generic request */
645 switch (typeReq) {
646 case GetHubStatus:
647 case GetPortStatus:
648 len = 4;
649 break;
650 case GetHubDescriptor:
651 len = sizeof (struct usb_hub_descriptor);
652 break;
653 case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
654 /* len is returned by hub_control */
655 break;
656 }
657 status = hcd->driver->hub_control (hcd,
658 typeReq, wValue, wIndex,
659 tbuf, wLength);
660
661 if (typeReq == GetHubDescriptor)
662 usb_hub_adjust_deviceremovable(hcd->self.root_hub,
663 (struct usb_hub_descriptor *)tbuf);
664 break;
665 error:
666 /* "protocol stall" on error */
667 status = -EPIPE;
668 }
669
670 if (status < 0) {
671 len = 0;
672 if (status != -EPIPE) {
673 dev_dbg (hcd->self.controller,
674 "CTRL: TypeReq=0x%x val=0x%x "
675 "idx=0x%x len=%d ==> %d\n",
676 typeReq, wValue, wIndex,
677 wLength, status);
678 }
679 } else if (status > 0) {
680 /* hub_control may return the length of data copied. */
681 len = status;
682 status = 0;
683 }
684 if (len) {
685 if (urb->transfer_buffer_length < len)
686 len = urb->transfer_buffer_length;
687 urb->actual_length = len;
688 /* always USB_DIR_IN, toward host */
689 memcpy (ubuf, bufp, len);
690
691 /* report whether RH hardware supports remote wakeup */
692 if (patch_wakeup &&
693 len > offsetof (struct usb_config_descriptor,
694 bmAttributes))
695 ((struct usb_config_descriptor *)ubuf)->bmAttributes
696 |= USB_CONFIG_ATT_WAKEUP;
697
698 /* report whether RH hardware has an integrated TT */
699 if (patch_protocol &&
700 len > offsetof(struct usb_device_descriptor,
701 bDeviceProtocol))
702 ((struct usb_device_descriptor *) ubuf)->
703 bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
704 }
705
706 kfree(tbuf);
707 err_alloc:
708
709 /* any errors get returned through the urb completion */
710 spin_lock_irq(&hcd_root_hub_lock);
711 usb_hcd_unlink_urb_from_ep(hcd, urb);
712 usb_hcd_giveback_urb(hcd, urb, status);
713 spin_unlock_irq(&hcd_root_hub_lock);
714 return 0;
715 }
716
717 /*-------------------------------------------------------------------------*/
718
719 /*
720 * Root Hub interrupt transfers are polled using a timer if the
721 * driver requests it; otherwise the driver is responsible for
722 * calling usb_hcd_poll_rh_status() when an event occurs.
723 *
724 * Completions are called in_interrupt(), but they may or may not
725 * be in_irq().
726 */
usb_hcd_poll_rh_status(struct usb_hcd * hcd)727 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
728 {
729 struct urb *urb;
730 int length;
731 unsigned long flags;
732 char buffer[6]; /* Any root hubs with > 31 ports? */
733
734 if (unlikely(!hcd->rh_pollable))
735 return;
736 if (!hcd->uses_new_polling && !hcd->status_urb)
737 return;
738
739 length = hcd->driver->hub_status_data(hcd, buffer);
740 if (length > 0) {
741
742 /* try to complete the status urb */
743 spin_lock_irqsave(&hcd_root_hub_lock, flags);
744 urb = hcd->status_urb;
745 if (urb) {
746 clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
747 hcd->status_urb = NULL;
748 urb->actual_length = length;
749 memcpy(urb->transfer_buffer, buffer, length);
750
751 usb_hcd_unlink_urb_from_ep(hcd, urb);
752 usb_hcd_giveback_urb(hcd, urb, 0);
753 } else {
754 length = 0;
755 set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
756 }
757 spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
758 }
759
760 /* The USB 2.0 spec says 256 ms. This is close enough and won't
761 * exceed that limit if HZ is 100. The math is more clunky than
762 * maybe expected, this is to make sure that all timers for USB devices
763 * fire at the same time to give the CPU a break in between */
764 if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
765 (length == 0 && hcd->status_urb != NULL))
766 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
767 }
768 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
769
770 /* timer callback */
rh_timer_func(unsigned long _hcd)771 static void rh_timer_func (unsigned long _hcd)
772 {
773 usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
774 }
775
776 /*-------------------------------------------------------------------------*/
777
rh_queue_status(struct usb_hcd * hcd,struct urb * urb)778 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
779 {
780 int retval;
781 unsigned long flags;
782 unsigned len = 1 + (urb->dev->maxchild / 8);
783
784 spin_lock_irqsave (&hcd_root_hub_lock, flags);
785 if (hcd->status_urb || urb->transfer_buffer_length < len) {
786 dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
787 retval = -EINVAL;
788 goto done;
789 }
790
791 retval = usb_hcd_link_urb_to_ep(hcd, urb);
792 if (retval)
793 goto done;
794
795 hcd->status_urb = urb;
796 urb->hcpriv = hcd; /* indicate it's queued */
797 if (!hcd->uses_new_polling)
798 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
799
800 /* If a status change has already occurred, report it ASAP */
801 else if (HCD_POLL_PENDING(hcd))
802 mod_timer(&hcd->rh_timer, jiffies);
803 retval = 0;
804 done:
805 spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
806 return retval;
807 }
808
rh_urb_enqueue(struct usb_hcd * hcd,struct urb * urb)809 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
810 {
811 if (usb_endpoint_xfer_int(&urb->ep->desc))
812 return rh_queue_status (hcd, urb);
813 if (usb_endpoint_xfer_control(&urb->ep->desc))
814 return rh_call_control (hcd, urb);
815 return -EINVAL;
816 }
817
818 /*-------------------------------------------------------------------------*/
819
820 /* Unlinks of root-hub control URBs are legal, but they don't do anything
821 * since these URBs always execute synchronously.
822 */
usb_rh_urb_dequeue(struct usb_hcd * hcd,struct urb * urb,int status)823 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
824 {
825 unsigned long flags;
826 int rc;
827
828 spin_lock_irqsave(&hcd_root_hub_lock, flags);
829 rc = usb_hcd_check_unlink_urb(hcd, urb, status);
830 if (rc)
831 goto done;
832
833 if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */
834 ; /* Do nothing */
835
836 } else { /* Status URB */
837 if (!hcd->uses_new_polling)
838 del_timer (&hcd->rh_timer);
839 if (urb == hcd->status_urb) {
840 hcd->status_urb = NULL;
841 usb_hcd_unlink_urb_from_ep(hcd, urb);
842 usb_hcd_giveback_urb(hcd, urb, status);
843 }
844 }
845 done:
846 spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
847 return rc;
848 }
849
850
851
852 /*
853 * Show & store the current value of authorized_default
854 */
authorized_default_show(struct device * dev,struct device_attribute * attr,char * buf)855 static ssize_t authorized_default_show(struct device *dev,
856 struct device_attribute *attr, char *buf)
857 {
858 struct usb_device *rh_usb_dev = to_usb_device(dev);
859 struct usb_bus *usb_bus = rh_usb_dev->bus;
860 struct usb_hcd *usb_hcd;
861
862 usb_hcd = bus_to_hcd(usb_bus);
863 return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
864 }
865
authorized_default_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)866 static ssize_t authorized_default_store(struct device *dev,
867 struct device_attribute *attr,
868 const char *buf, size_t size)
869 {
870 ssize_t result;
871 unsigned val;
872 struct usb_device *rh_usb_dev = to_usb_device(dev);
873 struct usb_bus *usb_bus = rh_usb_dev->bus;
874 struct usb_hcd *usb_hcd;
875
876 usb_hcd = bus_to_hcd(usb_bus);
877 result = sscanf(buf, "%u\n", &val);
878 if (result == 1) {
879 usb_hcd->authorized_default = val ? 1 : 0;
880 result = size;
881 } else {
882 result = -EINVAL;
883 }
884 return result;
885 }
886 static DEVICE_ATTR_RW(authorized_default);
887
888 /* Group all the USB bus attributes */
889 static struct attribute *usb_bus_attrs[] = {
890 &dev_attr_authorized_default.attr,
891 NULL,
892 };
893
894 static struct attribute_group usb_bus_attr_group = {
895 .name = NULL, /* we want them in the same directory */
896 .attrs = usb_bus_attrs,
897 };
898
899
900
901 /*-------------------------------------------------------------------------*/
902
903 /**
904 * usb_bus_init - shared initialization code
905 * @bus: the bus structure being initialized
906 *
907 * This code is used to initialize a usb_bus structure, memory for which is
908 * separately managed.
909 */
usb_bus_init(struct usb_bus * bus)910 static void usb_bus_init (struct usb_bus *bus)
911 {
912 memset (&bus->devmap, 0, sizeof(struct usb_devmap));
913
914 bus->devnum_next = 1;
915
916 bus->root_hub = NULL;
917 bus->busnum = -1;
918 bus->bandwidth_allocated = 0;
919 bus->bandwidth_int_reqs = 0;
920 bus->bandwidth_isoc_reqs = 0;
921 mutex_init(&bus->devnum_next_mutex);
922
923 INIT_LIST_HEAD (&bus->bus_list);
924 }
925
926 /*-------------------------------------------------------------------------*/
927
928 /**
929 * usb_register_bus - registers the USB host controller with the usb core
930 * @bus: pointer to the bus to register
931 * Context: !in_interrupt()
932 *
933 * Assigns a bus number, and links the controller into usbcore data
934 * structures so that it can be seen by scanning the bus list.
935 *
936 * Return: 0 if successful. A negative error code otherwise.
937 */
usb_register_bus(struct usb_bus * bus)938 static int usb_register_bus(struct usb_bus *bus)
939 {
940 int result = -E2BIG;
941 int busnum;
942
943 mutex_lock(&usb_bus_list_lock);
944 busnum = find_next_zero_bit(busmap, USB_MAXBUS, 1);
945 if (busnum >= USB_MAXBUS) {
946 printk (KERN_ERR "%s: too many buses\n", usbcore_name);
947 goto error_find_busnum;
948 }
949 set_bit(busnum, busmap);
950 bus->busnum = busnum;
951
952 /* Add it to the local list of buses */
953 list_add (&bus->bus_list, &usb_bus_list);
954 mutex_unlock(&usb_bus_list_lock);
955
956 usb_notify_add_bus(bus);
957
958 dev_info (bus->controller, "new USB bus registered, assigned bus "
959 "number %d\n", bus->busnum);
960 return 0;
961
962 error_find_busnum:
963 mutex_unlock(&usb_bus_list_lock);
964 return result;
965 }
966
967 /**
968 * usb_deregister_bus - deregisters the USB host controller
969 * @bus: pointer to the bus to deregister
970 * Context: !in_interrupt()
971 *
972 * Recycles the bus number, and unlinks the controller from usbcore data
973 * structures so that it won't be seen by scanning the bus list.
974 */
usb_deregister_bus(struct usb_bus * bus)975 static void usb_deregister_bus (struct usb_bus *bus)
976 {
977 dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
978
979 /*
980 * NOTE: make sure that all the devices are removed by the
981 * controller code, as well as having it call this when cleaning
982 * itself up
983 */
984 mutex_lock(&usb_bus_list_lock);
985 list_del (&bus->bus_list);
986 mutex_unlock(&usb_bus_list_lock);
987
988 usb_notify_remove_bus(bus);
989
990 clear_bit(bus->busnum, busmap);
991 }
992
993 /**
994 * register_root_hub - called by usb_add_hcd() to register a root hub
995 * @hcd: host controller for this root hub
996 *
997 * This function registers the root hub with the USB subsystem. It sets up
998 * the device properly in the device tree and then calls usb_new_device()
999 * to register the usb device. It also assigns the root hub's USB address
1000 * (always 1).
1001 *
1002 * Return: 0 if successful. A negative error code otherwise.
1003 */
register_root_hub(struct usb_hcd * hcd)1004 static int register_root_hub(struct usb_hcd *hcd)
1005 {
1006 struct device *parent_dev = hcd->self.controller;
1007 struct usb_device *usb_dev = hcd->self.root_hub;
1008 const int devnum = 1;
1009 int retval;
1010
1011 usb_dev->devnum = devnum;
1012 usb_dev->bus->devnum_next = devnum + 1;
1013 memset (&usb_dev->bus->devmap.devicemap, 0,
1014 sizeof usb_dev->bus->devmap.devicemap);
1015 set_bit (devnum, usb_dev->bus->devmap.devicemap);
1016 usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1017
1018 mutex_lock(&usb_bus_list_lock);
1019
1020 usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1021 retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1022 if (retval != sizeof usb_dev->descriptor) {
1023 mutex_unlock(&usb_bus_list_lock);
1024 dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1025 dev_name(&usb_dev->dev), retval);
1026 return (retval < 0) ? retval : -EMSGSIZE;
1027 }
1028 if (usb_dev->speed == USB_SPEED_SUPER) {
1029 retval = usb_get_bos_descriptor(usb_dev);
1030 if (retval < 0) {
1031 mutex_unlock(&usb_bus_list_lock);
1032 dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1033 dev_name(&usb_dev->dev), retval);
1034 return retval;
1035 }
1036 }
1037
1038 retval = usb_new_device (usb_dev);
1039 if (retval) {
1040 dev_err (parent_dev, "can't register root hub for %s, %d\n",
1041 dev_name(&usb_dev->dev), retval);
1042 } else {
1043 spin_lock_irq (&hcd_root_hub_lock);
1044 hcd->rh_registered = 1;
1045 spin_unlock_irq (&hcd_root_hub_lock);
1046
1047 /* Did the HC die before the root hub was registered? */
1048 if (HCD_DEAD(hcd))
1049 usb_hc_died (hcd); /* This time clean up */
1050 }
1051 mutex_unlock(&usb_bus_list_lock);
1052
1053 return retval;
1054 }
1055
1056 /*
1057 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1058 * @bus: the bus which the root hub belongs to
1059 * @portnum: the port which is being resumed
1060 *
1061 * HCDs should call this function when they know that a resume signal is
1062 * being sent to a root-hub port. The root hub will be prevented from
1063 * going into autosuspend until usb_hcd_end_port_resume() is called.
1064 *
1065 * The bus's private lock must be held by the caller.
1066 */
usb_hcd_start_port_resume(struct usb_bus * bus,int portnum)1067 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1068 {
1069 unsigned bit = 1 << portnum;
1070
1071 if (!(bus->resuming_ports & bit)) {
1072 bus->resuming_ports |= bit;
1073 pm_runtime_get_noresume(&bus->root_hub->dev);
1074 }
1075 }
1076 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1077
1078 /*
1079 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1080 * @bus: the bus which the root hub belongs to
1081 * @portnum: the port which is being resumed
1082 *
1083 * HCDs should call this function when they know that a resume signal has
1084 * stopped being sent to a root-hub port. The root hub will be allowed to
1085 * autosuspend again.
1086 *
1087 * The bus's private lock must be held by the caller.
1088 */
usb_hcd_end_port_resume(struct usb_bus * bus,int portnum)1089 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1090 {
1091 unsigned bit = 1 << portnum;
1092
1093 if (bus->resuming_ports & bit) {
1094 bus->resuming_ports &= ~bit;
1095 pm_runtime_put_noidle(&bus->root_hub->dev);
1096 }
1097 }
1098 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1099
1100 /*-------------------------------------------------------------------------*/
1101
1102 /**
1103 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1104 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1105 * @is_input: true iff the transaction sends data to the host
1106 * @isoc: true for isochronous transactions, false for interrupt ones
1107 * @bytecount: how many bytes in the transaction.
1108 *
1109 * Return: Approximate bus time in nanoseconds for a periodic transaction.
1110 *
1111 * Note:
1112 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1113 * scheduled in software, this function is only used for such scheduling.
1114 */
usb_calc_bus_time(int speed,int is_input,int isoc,int bytecount)1115 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1116 {
1117 unsigned long tmp;
1118
1119 switch (speed) {
1120 case USB_SPEED_LOW: /* INTR only */
1121 if (is_input) {
1122 tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1123 return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1124 } else {
1125 tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1126 return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1127 }
1128 case USB_SPEED_FULL: /* ISOC or INTR */
1129 if (isoc) {
1130 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1131 return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1132 } else {
1133 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1134 return 9107L + BW_HOST_DELAY + tmp;
1135 }
1136 case USB_SPEED_HIGH: /* ISOC or INTR */
1137 /* FIXME adjust for input vs output */
1138 if (isoc)
1139 tmp = HS_NSECS_ISO (bytecount);
1140 else
1141 tmp = HS_NSECS (bytecount);
1142 return tmp;
1143 default:
1144 pr_debug ("%s: bogus device speed!\n", usbcore_name);
1145 return -1;
1146 }
1147 }
1148 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1149
1150
1151 /*-------------------------------------------------------------------------*/
1152
1153 /*
1154 * Generic HC operations.
1155 */
1156
1157 /*-------------------------------------------------------------------------*/
1158
1159 /**
1160 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1161 * @hcd: host controller to which @urb was submitted
1162 * @urb: URB being submitted
1163 *
1164 * Host controller drivers should call this routine in their enqueue()
1165 * method. The HCD's private spinlock must be held and interrupts must
1166 * be disabled. The actions carried out here are required for URB
1167 * submission, as well as for endpoint shutdown and for usb_kill_urb.
1168 *
1169 * Return: 0 for no error, otherwise a negative error code (in which case
1170 * the enqueue() method must fail). If no error occurs but enqueue() fails
1171 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1172 * the private spinlock and returning.
1173 */
usb_hcd_link_urb_to_ep(struct usb_hcd * hcd,struct urb * urb)1174 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1175 {
1176 int rc = 0;
1177
1178 spin_lock(&hcd_urb_list_lock);
1179
1180 /* Check that the URB isn't being killed */
1181 if (unlikely(atomic_read(&urb->reject))) {
1182 rc = -EPERM;
1183 goto done;
1184 }
1185
1186 if (unlikely(!urb->ep->enabled)) {
1187 rc = -ENOENT;
1188 goto done;
1189 }
1190
1191 if (unlikely(!urb->dev->can_submit)) {
1192 rc = -EHOSTUNREACH;
1193 goto done;
1194 }
1195
1196 /*
1197 * Check the host controller's state and add the URB to the
1198 * endpoint's queue.
1199 */
1200 if (HCD_RH_RUNNING(hcd)) {
1201 urb->unlinked = 0;
1202 list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1203 } else {
1204 rc = -ESHUTDOWN;
1205 goto done;
1206 }
1207 done:
1208 spin_unlock(&hcd_urb_list_lock);
1209 return rc;
1210 }
1211 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1212
1213 /**
1214 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1215 * @hcd: host controller to which @urb was submitted
1216 * @urb: URB being checked for unlinkability
1217 * @status: error code to store in @urb if the unlink succeeds
1218 *
1219 * Host controller drivers should call this routine in their dequeue()
1220 * method. The HCD's private spinlock must be held and interrupts must
1221 * be disabled. The actions carried out here are required for making
1222 * sure than an unlink is valid.
1223 *
1224 * Return: 0 for no error, otherwise a negative error code (in which case
1225 * the dequeue() method must fail). The possible error codes are:
1226 *
1227 * -EIDRM: @urb was not submitted or has already completed.
1228 * The completion function may not have been called yet.
1229 *
1230 * -EBUSY: @urb has already been unlinked.
1231 */
usb_hcd_check_unlink_urb(struct usb_hcd * hcd,struct urb * urb,int status)1232 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1233 int status)
1234 {
1235 struct list_head *tmp;
1236
1237 /* insist the urb is still queued */
1238 list_for_each(tmp, &urb->ep->urb_list) {
1239 if (tmp == &urb->urb_list)
1240 break;
1241 }
1242 if (tmp != &urb->urb_list)
1243 return -EIDRM;
1244
1245 /* Any status except -EINPROGRESS means something already started to
1246 * unlink this URB from the hardware. So there's no more work to do.
1247 */
1248 if (urb->unlinked)
1249 return -EBUSY;
1250 urb->unlinked = status;
1251 return 0;
1252 }
1253 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1254
1255 /**
1256 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1257 * @hcd: host controller to which @urb was submitted
1258 * @urb: URB being unlinked
1259 *
1260 * Host controller drivers should call this routine before calling
1261 * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and
1262 * interrupts must be disabled. The actions carried out here are required
1263 * for URB completion.
1264 */
usb_hcd_unlink_urb_from_ep(struct usb_hcd * hcd,struct urb * urb)1265 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1266 {
1267 /* clear all state linking urb to this dev (and hcd) */
1268 spin_lock(&hcd_urb_list_lock);
1269 list_del_init(&urb->urb_list);
1270 spin_unlock(&hcd_urb_list_lock);
1271 }
1272 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1273
1274 /*
1275 * Some usb host controllers can only perform dma using a small SRAM area.
1276 * The usb core itself is however optimized for host controllers that can dma
1277 * using regular system memory - like pci devices doing bus mastering.
1278 *
1279 * To support host controllers with limited dma capabilities we provide dma
1280 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1281 * For this to work properly the host controller code must first use the
1282 * function dma_declare_coherent_memory() to point out which memory area
1283 * that should be used for dma allocations.
1284 *
1285 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1286 * dma using dma_alloc_coherent() which in turn allocates from the memory
1287 * area pointed out with dma_declare_coherent_memory().
1288 *
1289 * So, to summarize...
1290 *
1291 * - We need "local" memory, canonical example being
1292 * a small SRAM on a discrete controller being the
1293 * only memory that the controller can read ...
1294 * (a) "normal" kernel memory is no good, and
1295 * (b) there's not enough to share
1296 *
1297 * - The only *portable* hook for such stuff in the
1298 * DMA framework is dma_declare_coherent_memory()
1299 *
1300 * - So we use that, even though the primary requirement
1301 * is that the memory be "local" (hence addressable
1302 * by that device), not "coherent".
1303 *
1304 */
1305
hcd_alloc_coherent(struct usb_bus * bus,gfp_t mem_flags,dma_addr_t * dma_handle,void ** vaddr_handle,size_t size,enum dma_data_direction dir)1306 static int hcd_alloc_coherent(struct usb_bus *bus,
1307 gfp_t mem_flags, dma_addr_t *dma_handle,
1308 void **vaddr_handle, size_t size,
1309 enum dma_data_direction dir)
1310 {
1311 unsigned char *vaddr;
1312
1313 if (*vaddr_handle == NULL) {
1314 WARN_ON_ONCE(1);
1315 return -EFAULT;
1316 }
1317
1318 vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1319 mem_flags, dma_handle);
1320 if (!vaddr)
1321 return -ENOMEM;
1322
1323 /*
1324 * Store the virtual address of the buffer at the end
1325 * of the allocated dma buffer. The size of the buffer
1326 * may be uneven so use unaligned functions instead
1327 * of just rounding up. It makes sense to optimize for
1328 * memory footprint over access speed since the amount
1329 * of memory available for dma may be limited.
1330 */
1331 put_unaligned((unsigned long)*vaddr_handle,
1332 (unsigned long *)(vaddr + size));
1333
1334 if (dir == DMA_TO_DEVICE)
1335 memcpy(vaddr, *vaddr_handle, size);
1336
1337 *vaddr_handle = vaddr;
1338 return 0;
1339 }
1340
hcd_free_coherent(struct usb_bus * bus,dma_addr_t * dma_handle,void ** vaddr_handle,size_t size,enum dma_data_direction dir)1341 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1342 void **vaddr_handle, size_t size,
1343 enum dma_data_direction dir)
1344 {
1345 unsigned char *vaddr = *vaddr_handle;
1346
1347 vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1348
1349 if (dir == DMA_FROM_DEVICE)
1350 memcpy(vaddr, *vaddr_handle, size);
1351
1352 hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1353
1354 *vaddr_handle = vaddr;
1355 *dma_handle = 0;
1356 }
1357
usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd * hcd,struct urb * urb)1358 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1359 {
1360 if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1361 dma_unmap_single(hcd->self.controller,
1362 urb->setup_dma,
1363 sizeof(struct usb_ctrlrequest),
1364 DMA_TO_DEVICE);
1365 else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1366 hcd_free_coherent(urb->dev->bus,
1367 &urb->setup_dma,
1368 (void **) &urb->setup_packet,
1369 sizeof(struct usb_ctrlrequest),
1370 DMA_TO_DEVICE);
1371
1372 /* Make it safe to call this routine more than once */
1373 urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1374 }
1375 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1376
unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)1377 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1378 {
1379 if (hcd->driver->unmap_urb_for_dma)
1380 hcd->driver->unmap_urb_for_dma(hcd, urb);
1381 else
1382 usb_hcd_unmap_urb_for_dma(hcd, urb);
1383 }
1384
usb_hcd_unmap_urb_for_dma(struct usb_hcd * hcd,struct urb * urb)1385 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1386 {
1387 enum dma_data_direction dir;
1388
1389 usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1390
1391 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1392 if (urb->transfer_flags & URB_DMA_MAP_SG)
1393 dma_unmap_sg(hcd->self.controller,
1394 urb->sg,
1395 urb->num_sgs,
1396 dir);
1397 else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1398 dma_unmap_page(hcd->self.controller,
1399 urb->transfer_dma,
1400 urb->transfer_buffer_length,
1401 dir);
1402 else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1403 dma_unmap_single(hcd->self.controller,
1404 urb->transfer_dma,
1405 urb->transfer_buffer_length,
1406 dir);
1407 else if (urb->transfer_flags & URB_MAP_LOCAL)
1408 hcd_free_coherent(urb->dev->bus,
1409 &urb->transfer_dma,
1410 &urb->transfer_buffer,
1411 urb->transfer_buffer_length,
1412 dir);
1413
1414 /* Make it safe to call this routine more than once */
1415 urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1416 URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1417 }
1418 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1419
map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)1420 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1421 gfp_t mem_flags)
1422 {
1423 if (hcd->driver->map_urb_for_dma)
1424 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1425 else
1426 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1427 }
1428
usb_hcd_map_urb_for_dma(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)1429 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1430 gfp_t mem_flags)
1431 {
1432 enum dma_data_direction dir;
1433 int ret = 0;
1434
1435 /* Map the URB's buffers for DMA access.
1436 * Lower level HCD code should use *_dma exclusively,
1437 * unless it uses pio or talks to another transport,
1438 * or uses the provided scatter gather list for bulk.
1439 */
1440
1441 if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1442 if (hcd->self.uses_pio_for_control)
1443 return ret;
1444 if (hcd->self.uses_dma) {
1445 urb->setup_dma = dma_map_single(
1446 hcd->self.controller,
1447 urb->setup_packet,
1448 sizeof(struct usb_ctrlrequest),
1449 DMA_TO_DEVICE);
1450 if (dma_mapping_error(hcd->self.controller,
1451 urb->setup_dma))
1452 return -EAGAIN;
1453 urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1454 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1455 ret = hcd_alloc_coherent(
1456 urb->dev->bus, mem_flags,
1457 &urb->setup_dma,
1458 (void **)&urb->setup_packet,
1459 sizeof(struct usb_ctrlrequest),
1460 DMA_TO_DEVICE);
1461 if (ret)
1462 return ret;
1463 urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1464 }
1465 }
1466
1467 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1468 if (urb->transfer_buffer_length != 0
1469 && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1470 if (hcd->self.uses_dma) {
1471 if (urb->num_sgs) {
1472 int n;
1473
1474 /* We don't support sg for isoc transfers ! */
1475 if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1476 WARN_ON(1);
1477 return -EINVAL;
1478 }
1479
1480 n = dma_map_sg(
1481 hcd->self.controller,
1482 urb->sg,
1483 urb->num_sgs,
1484 dir);
1485 if (n <= 0)
1486 ret = -EAGAIN;
1487 else
1488 urb->transfer_flags |= URB_DMA_MAP_SG;
1489 urb->num_mapped_sgs = n;
1490 if (n != urb->num_sgs)
1491 urb->transfer_flags |=
1492 URB_DMA_SG_COMBINED;
1493 } else if (urb->sg) {
1494 struct scatterlist *sg = urb->sg;
1495 urb->transfer_dma = dma_map_page(
1496 hcd->self.controller,
1497 sg_page(sg),
1498 sg->offset,
1499 urb->transfer_buffer_length,
1500 dir);
1501 if (dma_mapping_error(hcd->self.controller,
1502 urb->transfer_dma))
1503 ret = -EAGAIN;
1504 else
1505 urb->transfer_flags |= URB_DMA_MAP_PAGE;
1506 } else if (is_vmalloc_addr(urb->transfer_buffer)) {
1507 WARN_ONCE(1, "transfer buffer not dma capable\n");
1508 ret = -EAGAIN;
1509 } else {
1510 urb->transfer_dma = dma_map_single(
1511 hcd->self.controller,
1512 urb->transfer_buffer,
1513 urb->transfer_buffer_length,
1514 dir);
1515 if (dma_mapping_error(hcd->self.controller,
1516 urb->transfer_dma))
1517 ret = -EAGAIN;
1518 else
1519 urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1520 }
1521 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1522 ret = hcd_alloc_coherent(
1523 urb->dev->bus, mem_flags,
1524 &urb->transfer_dma,
1525 &urb->transfer_buffer,
1526 urb->transfer_buffer_length,
1527 dir);
1528 if (ret == 0)
1529 urb->transfer_flags |= URB_MAP_LOCAL;
1530 }
1531 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1532 URB_SETUP_MAP_LOCAL)))
1533 usb_hcd_unmap_urb_for_dma(hcd, urb);
1534 }
1535 return ret;
1536 }
1537 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1538
1539 /*-------------------------------------------------------------------------*/
1540
1541 /* may be called in any context with a valid urb->dev usecount
1542 * caller surrenders "ownership" of urb
1543 * expects usb_submit_urb() to have sanity checked and conditioned all
1544 * inputs in the urb
1545 */
usb_hcd_submit_urb(struct urb * urb,gfp_t mem_flags)1546 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1547 {
1548 int status;
1549 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1550
1551 /* increment urb's reference count as part of giving it to the HCD
1552 * (which will control it). HCD guarantees that it either returns
1553 * an error or calls giveback(), but not both.
1554 */
1555 usb_get_urb(urb);
1556 atomic_inc(&urb->use_count);
1557 atomic_inc(&urb->dev->urbnum);
1558 usbmon_urb_submit(&hcd->self, urb);
1559
1560 /* NOTE requirements on root-hub callers (usbfs and the hub
1561 * driver, for now): URBs' urb->transfer_buffer must be
1562 * valid and usb_buffer_{sync,unmap}() not be needed, since
1563 * they could clobber root hub response data. Also, control
1564 * URBs must be submitted in process context with interrupts
1565 * enabled.
1566 */
1567
1568 if (is_root_hub(urb->dev)) {
1569 status = rh_urb_enqueue(hcd, urb);
1570 } else {
1571 status = map_urb_for_dma(hcd, urb, mem_flags);
1572 if (likely(status == 0)) {
1573 status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1574 if (unlikely(status))
1575 unmap_urb_for_dma(hcd, urb);
1576 }
1577 }
1578
1579 if (unlikely(status)) {
1580 usbmon_urb_submit_error(&hcd->self, urb, status);
1581 urb->hcpriv = NULL;
1582 INIT_LIST_HEAD(&urb->urb_list);
1583 atomic_dec(&urb->use_count);
1584 atomic_dec(&urb->dev->urbnum);
1585 if (atomic_read(&urb->reject))
1586 wake_up(&usb_kill_urb_queue);
1587 usb_put_urb(urb);
1588 }
1589 return status;
1590 }
1591
1592 /*-------------------------------------------------------------------------*/
1593
1594 /* this makes the hcd giveback() the urb more quickly, by kicking it
1595 * off hardware queues (which may take a while) and returning it as
1596 * soon as practical. we've already set up the urb's return status,
1597 * but we can't know if the callback completed already.
1598 */
unlink1(struct usb_hcd * hcd,struct urb * urb,int status)1599 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1600 {
1601 int value;
1602
1603 if (is_root_hub(urb->dev))
1604 value = usb_rh_urb_dequeue(hcd, urb, status);
1605 else {
1606
1607 /* The only reason an HCD might fail this call is if
1608 * it has not yet fully queued the urb to begin with.
1609 * Such failures should be harmless. */
1610 value = hcd->driver->urb_dequeue(hcd, urb, status);
1611 }
1612 return value;
1613 }
1614
1615 /*
1616 * called in any context
1617 *
1618 * caller guarantees urb won't be recycled till both unlink()
1619 * and the urb's completion function return
1620 */
usb_hcd_unlink_urb(struct urb * urb,int status)1621 int usb_hcd_unlink_urb (struct urb *urb, int status)
1622 {
1623 struct usb_hcd *hcd;
1624 struct usb_device *udev = urb->dev;
1625 int retval = -EIDRM;
1626 unsigned long flags;
1627
1628 /* Prevent the device and bus from going away while
1629 * the unlink is carried out. If they are already gone
1630 * then urb->use_count must be 0, since disconnected
1631 * devices can't have any active URBs.
1632 */
1633 spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1634 if (atomic_read(&urb->use_count) > 0) {
1635 retval = 0;
1636 usb_get_dev(udev);
1637 }
1638 spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1639 if (retval == 0) {
1640 hcd = bus_to_hcd(urb->dev->bus);
1641 retval = unlink1(hcd, urb, status);
1642 if (retval == 0)
1643 retval = -EINPROGRESS;
1644 else if (retval != -EIDRM && retval != -EBUSY)
1645 dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1646 urb, retval);
1647 usb_put_dev(udev);
1648 }
1649 return retval;
1650 }
1651
1652 /*-------------------------------------------------------------------------*/
1653
__usb_hcd_giveback_urb(struct urb * urb)1654 static void __usb_hcd_giveback_urb(struct urb *urb)
1655 {
1656 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1657 struct usb_anchor *anchor = urb->anchor;
1658 int status = urb->unlinked;
1659 unsigned long flags;
1660
1661 urb->hcpriv = NULL;
1662 if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1663 urb->actual_length < urb->transfer_buffer_length &&
1664 !status))
1665 status = -EREMOTEIO;
1666
1667 unmap_urb_for_dma(hcd, urb);
1668 usbmon_urb_complete(&hcd->self, urb, status);
1669 usb_anchor_suspend_wakeups(anchor);
1670 usb_unanchor_urb(urb);
1671 if (likely(status == 0))
1672 usb_led_activity(USB_LED_EVENT_HOST);
1673
1674 /* pass ownership to the completion handler */
1675 urb->status = status;
1676
1677 /*
1678 * We disable local IRQs here avoid possible deadlock because
1679 * drivers may call spin_lock() to hold lock which might be
1680 * acquired in one hard interrupt handler.
1681 *
1682 * The local_irq_save()/local_irq_restore() around complete()
1683 * will be removed if current USB drivers have been cleaned up
1684 * and no one may trigger the above deadlock situation when
1685 * running complete() in tasklet.
1686 */
1687 local_irq_save(flags);
1688 urb->complete(urb);
1689 local_irq_restore(flags);
1690
1691 usb_anchor_resume_wakeups(anchor);
1692 atomic_dec(&urb->use_count);
1693 if (unlikely(atomic_read(&urb->reject)))
1694 wake_up(&usb_kill_urb_queue);
1695 usb_put_urb(urb);
1696 }
1697
usb_giveback_urb_bh(unsigned long param)1698 static void usb_giveback_urb_bh(unsigned long param)
1699 {
1700 struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1701 struct list_head local_list;
1702
1703 spin_lock_irq(&bh->lock);
1704 bh->running = true;
1705 restart:
1706 list_replace_init(&bh->head, &local_list);
1707 spin_unlock_irq(&bh->lock);
1708
1709 while (!list_empty(&local_list)) {
1710 struct urb *urb;
1711
1712 urb = list_entry(local_list.next, struct urb, urb_list);
1713 list_del_init(&urb->urb_list);
1714 bh->completing_ep = urb->ep;
1715 __usb_hcd_giveback_urb(urb);
1716 bh->completing_ep = NULL;
1717 }
1718
1719 /* check if there are new URBs to giveback */
1720 spin_lock_irq(&bh->lock);
1721 if (!list_empty(&bh->head))
1722 goto restart;
1723 bh->running = false;
1724 spin_unlock_irq(&bh->lock);
1725 }
1726
1727 /**
1728 * usb_hcd_giveback_urb - return URB from HCD to device driver
1729 * @hcd: host controller returning the URB
1730 * @urb: urb being returned to the USB device driver.
1731 * @status: completion status code for the URB.
1732 * Context: in_interrupt()
1733 *
1734 * This hands the URB from HCD to its USB device driver, using its
1735 * completion function. The HCD has freed all per-urb resources
1736 * (and is done using urb->hcpriv). It also released all HCD locks;
1737 * the device driver won't cause problems if it frees, modifies,
1738 * or resubmits this URB.
1739 *
1740 * If @urb was unlinked, the value of @status will be overridden by
1741 * @urb->unlinked. Erroneous short transfers are detected in case
1742 * the HCD hasn't checked for them.
1743 */
usb_hcd_giveback_urb(struct usb_hcd * hcd,struct urb * urb,int status)1744 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1745 {
1746 struct giveback_urb_bh *bh;
1747 bool running, high_prio_bh;
1748
1749 /* pass status to tasklet via unlinked */
1750 if (likely(!urb->unlinked))
1751 urb->unlinked = status;
1752
1753 if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1754 __usb_hcd_giveback_urb(urb);
1755 return;
1756 }
1757
1758 if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1759 bh = &hcd->high_prio_bh;
1760 high_prio_bh = true;
1761 } else {
1762 bh = &hcd->low_prio_bh;
1763 high_prio_bh = false;
1764 }
1765
1766 spin_lock(&bh->lock);
1767 list_add_tail(&urb->urb_list, &bh->head);
1768 running = bh->running;
1769 spin_unlock(&bh->lock);
1770
1771 if (running)
1772 ;
1773 else if (high_prio_bh)
1774 tasklet_hi_schedule(&bh->bh);
1775 else
1776 tasklet_schedule(&bh->bh);
1777 }
1778 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1779
1780 /*-------------------------------------------------------------------------*/
1781
1782 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1783 * queue to drain completely. The caller must first insure that no more
1784 * URBs can be submitted for this endpoint.
1785 */
usb_hcd_flush_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)1786 void usb_hcd_flush_endpoint(struct usb_device *udev,
1787 struct usb_host_endpoint *ep)
1788 {
1789 struct usb_hcd *hcd;
1790 struct urb *urb;
1791
1792 if (!ep)
1793 return;
1794 might_sleep();
1795 hcd = bus_to_hcd(udev->bus);
1796
1797 /* No more submits can occur */
1798 spin_lock_irq(&hcd_urb_list_lock);
1799 rescan:
1800 list_for_each_entry (urb, &ep->urb_list, urb_list) {
1801 int is_in;
1802
1803 if (urb->unlinked)
1804 continue;
1805 usb_get_urb (urb);
1806 is_in = usb_urb_dir_in(urb);
1807 spin_unlock(&hcd_urb_list_lock);
1808
1809 /* kick hcd */
1810 unlink1(hcd, urb, -ESHUTDOWN);
1811 dev_dbg (hcd->self.controller,
1812 "shutdown urb %pK ep%d%s%s\n",
1813 urb, usb_endpoint_num(&ep->desc),
1814 is_in ? "in" : "out",
1815 ({ char *s;
1816
1817 switch (usb_endpoint_type(&ep->desc)) {
1818 case USB_ENDPOINT_XFER_CONTROL:
1819 s = ""; break;
1820 case USB_ENDPOINT_XFER_BULK:
1821 s = "-bulk"; break;
1822 case USB_ENDPOINT_XFER_INT:
1823 s = "-intr"; break;
1824 default:
1825 s = "-iso"; break;
1826 };
1827 s;
1828 }));
1829 usb_put_urb (urb);
1830
1831 /* list contents may have changed */
1832 spin_lock(&hcd_urb_list_lock);
1833 goto rescan;
1834 }
1835 spin_unlock_irq(&hcd_urb_list_lock);
1836
1837 /* Wait until the endpoint queue is completely empty */
1838 while (!list_empty (&ep->urb_list)) {
1839 spin_lock_irq(&hcd_urb_list_lock);
1840
1841 /* The list may have changed while we acquired the spinlock */
1842 urb = NULL;
1843 if (!list_empty (&ep->urb_list)) {
1844 urb = list_entry (ep->urb_list.prev, struct urb,
1845 urb_list);
1846 usb_get_urb (urb);
1847 }
1848 spin_unlock_irq(&hcd_urb_list_lock);
1849
1850 if (urb) {
1851 usb_kill_urb (urb);
1852 usb_put_urb (urb);
1853 }
1854 }
1855 }
1856
1857 /**
1858 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1859 * the bus bandwidth
1860 * @udev: target &usb_device
1861 * @new_config: new configuration to install
1862 * @cur_alt: the current alternate interface setting
1863 * @new_alt: alternate interface setting that is being installed
1864 *
1865 * To change configurations, pass in the new configuration in new_config,
1866 * and pass NULL for cur_alt and new_alt.
1867 *
1868 * To reset a device's configuration (put the device in the ADDRESSED state),
1869 * pass in NULL for new_config, cur_alt, and new_alt.
1870 *
1871 * To change alternate interface settings, pass in NULL for new_config,
1872 * pass in the current alternate interface setting in cur_alt,
1873 * and pass in the new alternate interface setting in new_alt.
1874 *
1875 * Return: An error if the requested bandwidth change exceeds the
1876 * bus bandwidth or host controller internal resources.
1877 */
usb_hcd_alloc_bandwidth(struct usb_device * udev,struct usb_host_config * new_config,struct usb_host_interface * cur_alt,struct usb_host_interface * new_alt)1878 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1879 struct usb_host_config *new_config,
1880 struct usb_host_interface *cur_alt,
1881 struct usb_host_interface *new_alt)
1882 {
1883 int num_intfs, i, j;
1884 struct usb_host_interface *alt = NULL;
1885 int ret = 0;
1886 struct usb_hcd *hcd;
1887 struct usb_host_endpoint *ep;
1888
1889 hcd = bus_to_hcd(udev->bus);
1890 if (!hcd->driver->check_bandwidth)
1891 return 0;
1892
1893 /* Configuration is being removed - set configuration 0 */
1894 if (!new_config && !cur_alt) {
1895 for (i = 1; i < 16; ++i) {
1896 ep = udev->ep_out[i];
1897 if (ep)
1898 hcd->driver->drop_endpoint(hcd, udev, ep);
1899 ep = udev->ep_in[i];
1900 if (ep)
1901 hcd->driver->drop_endpoint(hcd, udev, ep);
1902 }
1903 hcd->driver->check_bandwidth(hcd, udev);
1904 return 0;
1905 }
1906 /* Check if the HCD says there's enough bandwidth. Enable all endpoints
1907 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1908 * of the bus. There will always be bandwidth for endpoint 0, so it's
1909 * ok to exclude it.
1910 */
1911 if (new_config) {
1912 num_intfs = new_config->desc.bNumInterfaces;
1913 /* Remove endpoints (except endpoint 0, which is always on the
1914 * schedule) from the old config from the schedule
1915 */
1916 for (i = 1; i < 16; ++i) {
1917 ep = udev->ep_out[i];
1918 if (ep) {
1919 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1920 if (ret < 0)
1921 goto reset;
1922 }
1923 ep = udev->ep_in[i];
1924 if (ep) {
1925 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1926 if (ret < 0)
1927 goto reset;
1928 }
1929 }
1930 for (i = 0; i < num_intfs; ++i) {
1931 struct usb_host_interface *first_alt;
1932 int iface_num;
1933
1934 first_alt = &new_config->intf_cache[i]->altsetting[0];
1935 iface_num = first_alt->desc.bInterfaceNumber;
1936 /* Set up endpoints for alternate interface setting 0 */
1937 alt = usb_find_alt_setting(new_config, iface_num, 0);
1938 if (!alt)
1939 /* No alt setting 0? Pick the first setting. */
1940 alt = first_alt;
1941
1942 for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1943 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1944 if (ret < 0)
1945 goto reset;
1946 }
1947 }
1948 }
1949 if (cur_alt && new_alt) {
1950 struct usb_interface *iface = usb_ifnum_to_if(udev,
1951 cur_alt->desc.bInterfaceNumber);
1952
1953 if (!iface)
1954 return -EINVAL;
1955 if (iface->resetting_device) {
1956 /*
1957 * The USB core just reset the device, so the xHCI host
1958 * and the device will think alt setting 0 is installed.
1959 * However, the USB core will pass in the alternate
1960 * setting installed before the reset as cur_alt. Dig
1961 * out the alternate setting 0 structure, or the first
1962 * alternate setting if a broken device doesn't have alt
1963 * setting 0.
1964 */
1965 cur_alt = usb_altnum_to_altsetting(iface, 0);
1966 if (!cur_alt)
1967 cur_alt = &iface->altsetting[0];
1968 }
1969
1970 /* Drop all the endpoints in the current alt setting */
1971 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1972 ret = hcd->driver->drop_endpoint(hcd, udev,
1973 &cur_alt->endpoint[i]);
1974 if (ret < 0)
1975 goto reset;
1976 }
1977 /* Add all the endpoints in the new alt setting */
1978 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1979 ret = hcd->driver->add_endpoint(hcd, udev,
1980 &new_alt->endpoint[i]);
1981 if (ret < 0)
1982 goto reset;
1983 }
1984 }
1985 ret = hcd->driver->check_bandwidth(hcd, udev);
1986 reset:
1987 if (ret < 0)
1988 hcd->driver->reset_bandwidth(hcd, udev);
1989 return ret;
1990 }
1991
1992 /* Disables the endpoint: synchronizes with the hcd to make sure all
1993 * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must
1994 * have been called previously. Use for set_configuration, set_interface,
1995 * driver removal, physical disconnect.
1996 *
1997 * example: a qh stored in ep->hcpriv, holding state related to endpoint
1998 * type, maxpacket size, toggle, halt status, and scheduling.
1999 */
usb_hcd_disable_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)2000 void usb_hcd_disable_endpoint(struct usb_device *udev,
2001 struct usb_host_endpoint *ep)
2002 {
2003 struct usb_hcd *hcd;
2004
2005 might_sleep();
2006 hcd = bus_to_hcd(udev->bus);
2007 if (hcd->driver->endpoint_disable)
2008 hcd->driver->endpoint_disable(hcd, ep);
2009 }
2010
2011 /**
2012 * usb_hcd_reset_endpoint - reset host endpoint state
2013 * @udev: USB device.
2014 * @ep: the endpoint to reset.
2015 *
2016 * Resets any host endpoint state such as the toggle bit, sequence
2017 * number and current window.
2018 */
usb_hcd_reset_endpoint(struct usb_device * udev,struct usb_host_endpoint * ep)2019 void usb_hcd_reset_endpoint(struct usb_device *udev,
2020 struct usb_host_endpoint *ep)
2021 {
2022 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2023
2024 if (hcd->driver->endpoint_reset)
2025 hcd->driver->endpoint_reset(hcd, ep);
2026 else {
2027 int epnum = usb_endpoint_num(&ep->desc);
2028 int is_out = usb_endpoint_dir_out(&ep->desc);
2029 int is_control = usb_endpoint_xfer_control(&ep->desc);
2030
2031 usb_settoggle(udev, epnum, is_out, 0);
2032 if (is_control)
2033 usb_settoggle(udev, epnum, !is_out, 0);
2034 }
2035 }
2036
2037 /**
2038 * usb_alloc_streams - allocate bulk endpoint stream IDs.
2039 * @interface: alternate setting that includes all endpoints.
2040 * @eps: array of endpoints that need streams.
2041 * @num_eps: number of endpoints in the array.
2042 * @num_streams: number of streams to allocate.
2043 * @mem_flags: flags hcd should use to allocate memory.
2044 *
2045 * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2046 * Drivers may queue multiple transfers to different stream IDs, which may
2047 * complete in a different order than they were queued.
2048 *
2049 * Return: On success, the number of allocated streams. On failure, a negative
2050 * error code.
2051 */
usb_alloc_streams(struct usb_interface * interface,struct usb_host_endpoint ** eps,unsigned int num_eps,unsigned int num_streams,gfp_t mem_flags)2052 int usb_alloc_streams(struct usb_interface *interface,
2053 struct usb_host_endpoint **eps, unsigned int num_eps,
2054 unsigned int num_streams, gfp_t mem_flags)
2055 {
2056 struct usb_hcd *hcd;
2057 struct usb_device *dev;
2058 int i, ret;
2059
2060 dev = interface_to_usbdev(interface);
2061 hcd = bus_to_hcd(dev->bus);
2062 if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2063 return -EINVAL;
2064 if (dev->speed != USB_SPEED_SUPER)
2065 return -EINVAL;
2066 if (dev->state < USB_STATE_CONFIGURED)
2067 return -ENODEV;
2068
2069 for (i = 0; i < num_eps; i++) {
2070 /* Streams only apply to bulk endpoints. */
2071 if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2072 return -EINVAL;
2073 /* Re-alloc is not allowed */
2074 if (eps[i]->streams)
2075 return -EINVAL;
2076 }
2077
2078 ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2079 num_streams, mem_flags);
2080 if (ret < 0)
2081 return ret;
2082
2083 for (i = 0; i < num_eps; i++)
2084 eps[i]->streams = ret;
2085
2086 return ret;
2087 }
2088 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2089
2090 /**
2091 * usb_free_streams - free bulk endpoint stream IDs.
2092 * @interface: alternate setting that includes all endpoints.
2093 * @eps: array of endpoints to remove streams from.
2094 * @num_eps: number of endpoints in the array.
2095 * @mem_flags: flags hcd should use to allocate memory.
2096 *
2097 * Reverts a group of bulk endpoints back to not using stream IDs.
2098 * Can fail if we are given bad arguments, or HCD is broken.
2099 *
2100 * Return: 0 on success. On failure, a negative error code.
2101 */
usb_free_streams(struct usb_interface * interface,struct usb_host_endpoint ** eps,unsigned int num_eps,gfp_t mem_flags)2102 int usb_free_streams(struct usb_interface *interface,
2103 struct usb_host_endpoint **eps, unsigned int num_eps,
2104 gfp_t mem_flags)
2105 {
2106 struct usb_hcd *hcd;
2107 struct usb_device *dev;
2108 int i, ret;
2109
2110 dev = interface_to_usbdev(interface);
2111 hcd = bus_to_hcd(dev->bus);
2112 if (dev->speed != USB_SPEED_SUPER)
2113 return -EINVAL;
2114
2115 /* Double-free is not allowed */
2116 for (i = 0; i < num_eps; i++)
2117 if (!eps[i] || !eps[i]->streams)
2118 return -EINVAL;
2119
2120 ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2121 if (ret < 0)
2122 return ret;
2123
2124 for (i = 0; i < num_eps; i++)
2125 eps[i]->streams = 0;
2126
2127 return ret;
2128 }
2129 EXPORT_SYMBOL_GPL(usb_free_streams);
2130
2131 /* Protect against drivers that try to unlink URBs after the device
2132 * is gone, by waiting until all unlinks for @udev are finished.
2133 * Since we don't currently track URBs by device, simply wait until
2134 * nothing is running in the locked region of usb_hcd_unlink_urb().
2135 */
usb_hcd_synchronize_unlinks(struct usb_device * udev)2136 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2137 {
2138 spin_lock_irq(&hcd_urb_unlink_lock);
2139 spin_unlock_irq(&hcd_urb_unlink_lock);
2140 }
2141
2142 /*-------------------------------------------------------------------------*/
2143
2144 /* called in any context */
usb_hcd_get_frame_number(struct usb_device * udev)2145 int usb_hcd_get_frame_number (struct usb_device *udev)
2146 {
2147 struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2148
2149 if (!HCD_RH_RUNNING(hcd))
2150 return -ESHUTDOWN;
2151 return hcd->driver->get_frame_number (hcd);
2152 }
2153
2154 /*-------------------------------------------------------------------------*/
2155
2156 #ifdef CONFIG_PM
2157
hcd_bus_suspend(struct usb_device * rhdev,pm_message_t msg)2158 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2159 {
2160 struct usb_hcd *hcd = container_of(rhdev->bus, struct usb_hcd, self);
2161 int status;
2162 int old_state = hcd->state;
2163
2164 dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2165 (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2166 rhdev->do_remote_wakeup);
2167 if (HCD_DEAD(hcd)) {
2168 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2169 return 0;
2170 }
2171
2172 if (!hcd->driver->bus_suspend) {
2173 status = -ENOENT;
2174 } else {
2175 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2176 hcd->state = HC_STATE_QUIESCING;
2177 status = hcd->driver->bus_suspend(hcd);
2178 }
2179 if (status == 0) {
2180 usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2181 hcd->state = HC_STATE_SUSPENDED;
2182
2183 /* Did we race with a root-hub wakeup event? */
2184 if (rhdev->do_remote_wakeup) {
2185 char buffer[6];
2186
2187 status = hcd->driver->hub_status_data(hcd, buffer);
2188 if (status != 0) {
2189 dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2190 hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2191 status = -EBUSY;
2192 }
2193 }
2194 } else {
2195 spin_lock_irq(&hcd_root_hub_lock);
2196 if (!HCD_DEAD(hcd)) {
2197 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2198 hcd->state = old_state;
2199 }
2200 spin_unlock_irq(&hcd_root_hub_lock);
2201 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2202 "suspend", status);
2203 }
2204 return status;
2205 }
2206
hcd_bus_resume(struct usb_device * rhdev,pm_message_t msg)2207 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2208 {
2209 struct usb_hcd *hcd = container_of(rhdev->bus, struct usb_hcd, self);
2210 int status;
2211 int old_state = hcd->state;
2212
2213 dev_dbg(&rhdev->dev, "usb %sresume\n",
2214 (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2215 if (HCD_DEAD(hcd)) {
2216 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2217 return 0;
2218 }
2219 if (!hcd->driver->bus_resume)
2220 return -ENOENT;
2221 if (HCD_RH_RUNNING(hcd))
2222 return 0;
2223
2224 hcd->state = HC_STATE_RESUMING;
2225 status = hcd->driver->bus_resume(hcd);
2226 clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2227 if (status == 0) {
2228 struct usb_device *udev;
2229 int port1;
2230
2231 spin_lock_irq(&hcd_root_hub_lock);
2232 if (!HCD_DEAD(hcd)) {
2233 usb_set_device_state(rhdev, rhdev->actconfig
2234 ? USB_STATE_CONFIGURED
2235 : USB_STATE_ADDRESS);
2236 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2237 hcd->state = HC_STATE_RUNNING;
2238 }
2239 spin_unlock_irq(&hcd_root_hub_lock);
2240
2241 /*
2242 * Check whether any of the enabled ports on the root hub are
2243 * unsuspended. If they are then a TRSMRCY delay is needed
2244 * (this is what the USB-2 spec calls a "global resume").
2245 * Otherwise we can skip the delay.
2246 */
2247 usb_hub_for_each_child(rhdev, port1, udev) {
2248 if (udev->state != USB_STATE_NOTATTACHED &&
2249 !udev->port_is_suspended) {
2250 usleep_range(10000, 11000); /* TRSMRCY */
2251 break;
2252 }
2253 }
2254 } else {
2255 hcd->state = old_state;
2256 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2257 "resume", status);
2258 if (status != -ESHUTDOWN)
2259 usb_hc_died(hcd);
2260 }
2261 return status;
2262 }
2263
2264 #endif /* CONFIG_PM */
2265
2266 #ifdef CONFIG_PM_RUNTIME
2267
2268 /* Workqueue routine for root-hub remote wakeup */
hcd_resume_work(struct work_struct * work)2269 static void hcd_resume_work(struct work_struct *work)
2270 {
2271 struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2272 struct usb_device *udev = hcd->self.root_hub;
2273
2274 usb_remote_wakeup(udev);
2275 }
2276
2277 /**
2278 * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2279 * @hcd: host controller for this root hub
2280 *
2281 * The USB host controller calls this function when its root hub is
2282 * suspended (with the remote wakeup feature enabled) and a remote
2283 * wakeup request is received. The routine submits a workqueue request
2284 * to resume the root hub (that is, manage its downstream ports again).
2285 */
usb_hcd_resume_root_hub(struct usb_hcd * hcd)2286 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2287 {
2288 unsigned long flags;
2289
2290 spin_lock_irqsave (&hcd_root_hub_lock, flags);
2291 if (hcd->rh_registered) {
2292 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2293 queue_work(pm_wq, &hcd->wakeup_work);
2294 }
2295 spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2296 }
2297 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2298
2299 #endif /* CONFIG_PM_RUNTIME */
2300
2301 /*-------------------------------------------------------------------------*/
2302
2303 #ifdef CONFIG_USB_OTG
2304
2305 /**
2306 * usb_bus_start_enum - start immediate enumeration (for OTG)
2307 * @bus: the bus (must use hcd framework)
2308 * @port_num: 1-based number of port; usually bus->otg_port
2309 * Context: in_interrupt()
2310 *
2311 * Starts enumeration, with an immediate reset followed later by
2312 * hub_wq identifying and possibly configuring the device.
2313 * This is needed by OTG controller drivers, where it helps meet
2314 * HNP protocol timing requirements for starting a port reset.
2315 *
2316 * Return: 0 if successful.
2317 */
usb_bus_start_enum(struct usb_bus * bus,unsigned port_num)2318 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2319 {
2320 struct usb_hcd *hcd;
2321 int status = -EOPNOTSUPP;
2322
2323 /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2324 * boards with root hubs hooked up to internal devices (instead of
2325 * just the OTG port) may need more attention to resetting...
2326 */
2327 hcd = container_of (bus, struct usb_hcd, self);
2328 if (port_num && hcd->driver->start_port_reset)
2329 status = hcd->driver->start_port_reset(hcd, port_num);
2330
2331 /* allocate hub_wq shortly after (first) root port reset finishes;
2332 * it may issue others, until at least 50 msecs have passed.
2333 */
2334 if (status == 0)
2335 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2336 return status;
2337 }
2338 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2339
2340 #endif
2341
2342 /*-------------------------------------------------------------------------*/
2343
2344 /**
2345 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2346 * @irq: the IRQ being raised
2347 * @__hcd: pointer to the HCD whose IRQ is being signaled
2348 *
2349 * If the controller isn't HALTed, calls the driver's irq handler.
2350 * Checks whether the controller is now dead.
2351 *
2352 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2353 */
usb_hcd_irq(int irq,void * __hcd)2354 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2355 {
2356 struct usb_hcd *hcd = __hcd;
2357 irqreturn_t rc;
2358
2359 if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2360 rc = IRQ_NONE;
2361 else if (hcd->driver->irq(hcd) == IRQ_NONE)
2362 rc = IRQ_NONE;
2363 else
2364 rc = IRQ_HANDLED;
2365
2366 return rc;
2367 }
2368 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2369
2370 /*-------------------------------------------------------------------------*/
2371
2372 /**
2373 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2374 * @hcd: pointer to the HCD representing the controller
2375 *
2376 * This is called by bus glue to report a USB host controller that died
2377 * while operations may still have been pending. It's called automatically
2378 * by the PCI glue, so only glue for non-PCI busses should need to call it.
2379 *
2380 * Only call this function with the primary HCD.
2381 */
usb_hc_died(struct usb_hcd * hcd)2382 void usb_hc_died (struct usb_hcd *hcd)
2383 {
2384 unsigned long flags;
2385
2386 dev_err (hcd->self.controller, "HC died; cleaning up\n");
2387
2388 spin_lock_irqsave (&hcd_root_hub_lock, flags);
2389 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2390 set_bit(HCD_FLAG_DEAD, &hcd->flags);
2391 if (hcd->rh_registered) {
2392 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2393
2394 /* make hub_wq clean up old urbs and devices */
2395 usb_set_device_state (hcd->self.root_hub,
2396 USB_STATE_NOTATTACHED);
2397 usb_kick_hub_wq(hcd->self.root_hub);
2398 }
2399 if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2400 hcd = hcd->shared_hcd;
2401 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2402 set_bit(HCD_FLAG_DEAD, &hcd->flags);
2403 if (hcd->rh_registered) {
2404 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2405
2406 /* make hub_wq clean up old urbs and devices */
2407 usb_set_device_state(hcd->self.root_hub,
2408 USB_STATE_NOTATTACHED);
2409 usb_kick_hub_wq(hcd->self.root_hub);
2410 }
2411 }
2412 spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2413 /* Make sure that the other roothub is also deallocated. */
2414 }
2415 EXPORT_SYMBOL_GPL (usb_hc_died);
2416
2417 /*-------------------------------------------------------------------------*/
2418
init_giveback_urb_bh(struct giveback_urb_bh * bh)2419 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2420 {
2421
2422 spin_lock_init(&bh->lock);
2423 INIT_LIST_HEAD(&bh->head);
2424 tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2425 }
2426
2427 /**
2428 * usb_create_shared_hcd - create and initialize an HCD structure
2429 * @driver: HC driver that will use this hcd
2430 * @dev: device for this HC, stored in hcd->self.controller
2431 * @bus_name: value to store in hcd->self.bus_name
2432 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2433 * PCI device. Only allocate certain resources for the primary HCD
2434 * Context: !in_interrupt()
2435 *
2436 * Allocate a struct usb_hcd, with extra space at the end for the
2437 * HC driver's private data. Initialize the generic members of the
2438 * hcd structure.
2439 *
2440 * Return: On success, a pointer to the created and initialized HCD structure.
2441 * On failure (e.g. if memory is unavailable), %NULL.
2442 */
usb_create_shared_hcd(const struct hc_driver * driver,struct device * dev,const char * bus_name,struct usb_hcd * primary_hcd)2443 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2444 struct device *dev, const char *bus_name,
2445 struct usb_hcd *primary_hcd)
2446 {
2447 struct usb_hcd *hcd;
2448
2449 hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2450 if (!hcd) {
2451 dev_dbg (dev, "hcd alloc failed\n");
2452 return NULL;
2453 }
2454 if (primary_hcd == NULL) {
2455 hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2456 GFP_KERNEL);
2457 if (!hcd->address0_mutex) {
2458 kfree(hcd);
2459 dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2460 return NULL;
2461 }
2462 mutex_init(hcd->address0_mutex);
2463 hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2464 GFP_KERNEL);
2465 if (!hcd->bandwidth_mutex) {
2466 kfree(hcd->address0_mutex);
2467 kfree(hcd);
2468 dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2469 return NULL;
2470 }
2471 mutex_init(hcd->bandwidth_mutex);
2472 dev_set_drvdata(dev, hcd);
2473 } else {
2474 mutex_lock(&usb_port_peer_mutex);
2475 hcd->address0_mutex = primary_hcd->address0_mutex;
2476 hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2477 hcd->primary_hcd = primary_hcd;
2478 primary_hcd->primary_hcd = primary_hcd;
2479 hcd->shared_hcd = primary_hcd;
2480 primary_hcd->shared_hcd = hcd;
2481 mutex_unlock(&usb_port_peer_mutex);
2482 }
2483
2484 kref_init(&hcd->kref);
2485
2486 usb_bus_init(&hcd->self);
2487 hcd->self.controller = dev;
2488 hcd->self.bus_name = bus_name;
2489 hcd->self.uses_dma = (dev->dma_mask != NULL);
2490
2491 init_timer(&hcd->rh_timer);
2492 hcd->rh_timer.function = rh_timer_func;
2493 hcd->rh_timer.data = (unsigned long) hcd;
2494 #ifdef CONFIG_PM_RUNTIME
2495 INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2496 #endif
2497
2498 hcd->driver = driver;
2499 hcd->speed = driver->flags & HCD_MASK;
2500 hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2501 "USB Host Controller";
2502 return hcd;
2503 }
2504 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2505
2506 /**
2507 * usb_create_hcd - create and initialize an HCD structure
2508 * @driver: HC driver that will use this hcd
2509 * @dev: device for this HC, stored in hcd->self.controller
2510 * @bus_name: value to store in hcd->self.bus_name
2511 * Context: !in_interrupt()
2512 *
2513 * Allocate a struct usb_hcd, with extra space at the end for the
2514 * HC driver's private data. Initialize the generic members of the
2515 * hcd structure.
2516 *
2517 * Return: On success, a pointer to the created and initialized HCD
2518 * structure. On failure (e.g. if memory is unavailable), %NULL.
2519 */
usb_create_hcd(const struct hc_driver * driver,struct device * dev,const char * bus_name)2520 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2521 struct device *dev, const char *bus_name)
2522 {
2523 return usb_create_shared_hcd(driver, dev, bus_name, NULL);
2524 }
2525 EXPORT_SYMBOL_GPL(usb_create_hcd);
2526
2527 /*
2528 * Roothubs that share one PCI device must also share the bandwidth mutex.
2529 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2530 * deallocated.
2531 *
2532 * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2533 * freed. When hcd_release() is called for either hcd in a peer set,
2534 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2535 */
hcd_release(struct kref * kref)2536 static void hcd_release(struct kref *kref)
2537 {
2538 struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2539
2540 mutex_lock(&usb_port_peer_mutex);
2541 if (hcd->shared_hcd) {
2542 struct usb_hcd *peer = hcd->shared_hcd;
2543
2544 peer->shared_hcd = NULL;
2545 peer->primary_hcd = NULL;
2546 } else {
2547 kfree(hcd->address0_mutex);
2548 kfree(hcd->bandwidth_mutex);
2549 }
2550 mutex_unlock(&usb_port_peer_mutex);
2551 kfree(hcd);
2552 }
2553
usb_get_hcd(struct usb_hcd * hcd)2554 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2555 {
2556 if (hcd)
2557 kref_get (&hcd->kref);
2558 return hcd;
2559 }
2560 EXPORT_SYMBOL_GPL(usb_get_hcd);
2561
usb_put_hcd(struct usb_hcd * hcd)2562 void usb_put_hcd (struct usb_hcd *hcd)
2563 {
2564 if (hcd)
2565 kref_put (&hcd->kref, hcd_release);
2566 }
2567 EXPORT_SYMBOL_GPL(usb_put_hcd);
2568
usb_hcd_is_primary_hcd(struct usb_hcd * hcd)2569 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2570 {
2571 if (!hcd->primary_hcd)
2572 return 1;
2573 return hcd == hcd->primary_hcd;
2574 }
2575 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2576
usb_hcd_find_raw_port_number(struct usb_hcd * hcd,int port1)2577 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2578 {
2579 if (!hcd->driver->find_raw_port_number)
2580 return port1;
2581
2582 return hcd->driver->find_raw_port_number(hcd, port1);
2583 }
2584
usb_hcd_request_irqs(struct usb_hcd * hcd,unsigned int irqnum,unsigned long irqflags)2585 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2586 unsigned int irqnum, unsigned long irqflags)
2587 {
2588 int retval;
2589
2590 if (hcd->driver->irq) {
2591
2592 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2593 hcd->driver->description, hcd->self.busnum);
2594 retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2595 hcd->irq_descr, hcd);
2596 if (retval != 0) {
2597 dev_err(hcd->self.controller,
2598 "request interrupt %d failed\n",
2599 irqnum);
2600 return retval;
2601 }
2602 hcd->irq = irqnum;
2603 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2604 (hcd->driver->flags & HCD_MEMORY) ?
2605 "io mem" : "io base",
2606 (unsigned long long)hcd->rsrc_start);
2607 } else {
2608 hcd->irq = 0;
2609 if (hcd->rsrc_start)
2610 dev_info(hcd->self.controller, "%s 0x%08llx\n",
2611 (hcd->driver->flags & HCD_MEMORY) ?
2612 "io mem" : "io base",
2613 (unsigned long long)hcd->rsrc_start);
2614 }
2615 return 0;
2616 }
2617
2618 /*
2619 * Before we free this root hub, flush in-flight peering attempts
2620 * and disable peer lookups
2621 */
usb_put_invalidate_rhdev(struct usb_hcd * hcd)2622 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2623 {
2624 struct usb_device *rhdev;
2625
2626 mutex_lock(&usb_port_peer_mutex);
2627 rhdev = hcd->self.root_hub;
2628 hcd->self.root_hub = NULL;
2629 mutex_unlock(&usb_port_peer_mutex);
2630 usb_put_dev(rhdev);
2631 }
2632
2633 /**
2634 * usb_add_hcd - finish generic HCD structure initialization and register
2635 * @hcd: the usb_hcd structure to initialize
2636 * @irqnum: Interrupt line to allocate
2637 * @irqflags: Interrupt type flags
2638 *
2639 * Finish the remaining parts of generic HCD initialization: allocate the
2640 * buffers of consistent memory, register the bus, request the IRQ line,
2641 * and call the driver's reset() and start() routines.
2642 */
usb_add_hcd(struct usb_hcd * hcd,unsigned int irqnum,unsigned long irqflags)2643 int usb_add_hcd(struct usb_hcd *hcd,
2644 unsigned int irqnum, unsigned long irqflags)
2645 {
2646 int retval;
2647 struct usb_device *rhdev;
2648
2649 if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
2650 struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0);
2651
2652 if (IS_ERR(phy)) {
2653 retval = PTR_ERR(phy);
2654 if (retval == -EPROBE_DEFER)
2655 return retval;
2656 } else {
2657 retval = usb_phy_init(phy);
2658 if (retval) {
2659 usb_put_phy(phy);
2660 return retval;
2661 }
2662 hcd->usb_phy = phy;
2663 hcd->remove_phy = 1;
2664 }
2665 }
2666
2667 if (IS_ENABLED(CONFIG_GENERIC_PHY)) {
2668 struct phy *phy = phy_get(hcd->self.controller, "usb");
2669
2670 if (IS_ERR(phy)) {
2671 retval = PTR_ERR(phy);
2672 if (retval == -EPROBE_DEFER)
2673 goto err_phy;
2674 } else {
2675 retval = phy_init(phy);
2676 if (retval) {
2677 phy_put(phy);
2678 goto err_phy;
2679 }
2680 retval = phy_power_on(phy);
2681 if (retval) {
2682 phy_exit(phy);
2683 phy_put(phy);
2684 goto err_phy;
2685 }
2686 hcd->phy = phy;
2687 }
2688 }
2689
2690 dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2691
2692 /* Keep old behaviour if authorized_default is not in [0, 1]. */
2693 if (authorized_default < 0 || authorized_default > 1)
2694 hcd->authorized_default = hcd->wireless ? 0 : 1;
2695 else
2696 hcd->authorized_default = authorized_default;
2697 set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2698
2699 /* HC is in reset state, but accessible. Now do the one-time init,
2700 * bottom up so that hcds can customize the root hubs before hub_wq
2701 * starts talking to them. (Note, bus id is assigned early too.)
2702 */
2703 if ((retval = hcd_buffer_create(hcd)) != 0) {
2704 dev_dbg(hcd->self.controller, "pool alloc failed\n");
2705 goto err_create_buf;
2706 }
2707
2708 if ((retval = usb_register_bus(&hcd->self)) < 0)
2709 goto err_register_bus;
2710
2711 if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
2712 dev_err(hcd->self.controller, "unable to allocate root hub\n");
2713 retval = -ENOMEM;
2714 goto err_allocate_root_hub;
2715 }
2716 mutex_lock(&usb_port_peer_mutex);
2717 hcd->self.root_hub = rhdev;
2718 mutex_unlock(&usb_port_peer_mutex);
2719
2720 switch (hcd->speed) {
2721 case HCD_USB11:
2722 rhdev->speed = USB_SPEED_FULL;
2723 break;
2724 case HCD_USB2:
2725 rhdev->speed = USB_SPEED_HIGH;
2726 break;
2727 case HCD_USB25:
2728 rhdev->speed = USB_SPEED_WIRELESS;
2729 break;
2730 case HCD_USB3:
2731 rhdev->speed = USB_SPEED_SUPER;
2732 break;
2733 default:
2734 retval = -EINVAL;
2735 goto err_set_rh_speed;
2736 }
2737
2738 /* wakeup flag init defaults to "everything works" for root hubs,
2739 * but drivers can override it in reset() if needed, along with
2740 * recording the overall controller's system wakeup capability.
2741 */
2742 device_set_wakeup_capable(&rhdev->dev, 1);
2743
2744 /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2745 * registered. But since the controller can die at any time,
2746 * let's initialize the flag before touching the hardware.
2747 */
2748 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2749
2750 /* "reset" is misnamed; its role is now one-time init. the controller
2751 * should already have been reset (and boot firmware kicked off etc).
2752 */
2753 if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
2754 dev_err(hcd->self.controller, "can't setup: %d\n", retval);
2755 goto err_hcd_driver_setup;
2756 }
2757 hcd->rh_pollable = 1;
2758
2759 /* NOTE: root hub and controller capabilities may not be the same */
2760 if (device_can_wakeup(hcd->self.controller)
2761 && device_can_wakeup(&hcd->self.root_hub->dev))
2762 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2763
2764 /* initialize tasklets */
2765 init_giveback_urb_bh(&hcd->high_prio_bh);
2766 init_giveback_urb_bh(&hcd->low_prio_bh);
2767
2768 /* enable irqs just before we start the controller,
2769 * if the BIOS provides legacy PCI irqs.
2770 */
2771 if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2772 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2773 if (retval)
2774 goto err_request_irq;
2775 }
2776
2777 hcd->state = HC_STATE_RUNNING;
2778 retval = hcd->driver->start(hcd);
2779 if (retval < 0) {
2780 dev_err(hcd->self.controller, "startup error %d\n", retval);
2781 goto err_hcd_driver_start;
2782 }
2783
2784 /* starting here, usbcore will pay attention to this root hub */
2785 if ((retval = register_root_hub(hcd)) != 0)
2786 goto err_register_root_hub;
2787
2788 retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2789 if (retval < 0) {
2790 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2791 retval);
2792 goto error_create_attr_group;
2793 }
2794 if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2795 usb_hcd_poll_rh_status(hcd);
2796
2797 return retval;
2798
2799 error_create_attr_group:
2800 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2801 if (HC_IS_RUNNING(hcd->state))
2802 hcd->state = HC_STATE_QUIESCING;
2803 spin_lock_irq(&hcd_root_hub_lock);
2804 hcd->rh_registered = 0;
2805 spin_unlock_irq(&hcd_root_hub_lock);
2806
2807 #ifdef CONFIG_PM_RUNTIME
2808 cancel_work_sync(&hcd->wakeup_work);
2809 #endif
2810 mutex_lock(&usb_bus_list_lock);
2811 usb_disconnect(&rhdev); /* Sets rhdev to NULL */
2812 mutex_unlock(&usb_bus_list_lock);
2813 err_register_root_hub:
2814 hcd->rh_pollable = 0;
2815 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2816 del_timer_sync(&hcd->rh_timer);
2817 hcd->driver->stop(hcd);
2818 hcd->state = HC_STATE_HALT;
2819 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2820 del_timer_sync(&hcd->rh_timer);
2821 err_hcd_driver_start:
2822 if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2823 free_irq(irqnum, hcd);
2824 err_request_irq:
2825 err_hcd_driver_setup:
2826 err_set_rh_speed:
2827 usb_put_invalidate_rhdev(hcd);
2828 err_allocate_root_hub:
2829 usb_deregister_bus(&hcd->self);
2830 err_register_bus:
2831 hcd_buffer_destroy(hcd);
2832 err_create_buf:
2833 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->phy) {
2834 phy_power_off(hcd->phy);
2835 phy_exit(hcd->phy);
2836 phy_put(hcd->phy);
2837 hcd->phy = NULL;
2838 }
2839 err_phy:
2840 if (hcd->remove_phy && hcd->usb_phy) {
2841 usb_phy_shutdown(hcd->usb_phy);
2842 usb_put_phy(hcd->usb_phy);
2843 hcd->usb_phy = NULL;
2844 }
2845 return retval;
2846 }
2847 EXPORT_SYMBOL_GPL(usb_add_hcd);
2848
2849 /**
2850 * usb_remove_hcd - shutdown processing for generic HCDs
2851 * @hcd: the usb_hcd structure to remove
2852 * Context: !in_interrupt()
2853 *
2854 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2855 * invoking the HCD's stop() method.
2856 */
usb_remove_hcd(struct usb_hcd * hcd)2857 void usb_remove_hcd(struct usb_hcd *hcd)
2858 {
2859 struct usb_device *rhdev = hcd->self.root_hub;
2860
2861 dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2862
2863 usb_get_dev(rhdev);
2864 sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2865
2866 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2867 if (HC_IS_RUNNING (hcd->state))
2868 hcd->state = HC_STATE_QUIESCING;
2869
2870 dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2871 spin_lock_irq (&hcd_root_hub_lock);
2872 hcd->rh_registered = 0;
2873 spin_unlock_irq (&hcd_root_hub_lock);
2874
2875 #ifdef CONFIG_PM_RUNTIME
2876 cancel_work_sync(&hcd->wakeup_work);
2877 #endif
2878
2879 mutex_lock(&usb_bus_list_lock);
2880 usb_disconnect(&rhdev); /* Sets rhdev to NULL */
2881 mutex_unlock(&usb_bus_list_lock);
2882
2883 /*
2884 * tasklet_kill() isn't needed here because:
2885 * - driver's disconnect() called from usb_disconnect() should
2886 * make sure its URBs are completed during the disconnect()
2887 * callback
2888 *
2889 * - it is too late to run complete() here since driver may have
2890 * been removed already now
2891 */
2892
2893 /* Prevent any more root-hub status calls from the timer.
2894 * The HCD might still restart the timer (if a port status change
2895 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2896 * the hub_status_data() callback.
2897 */
2898 hcd->rh_pollable = 0;
2899 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2900 del_timer_sync(&hcd->rh_timer);
2901
2902 hcd->driver->stop(hcd);
2903 hcd->state = HC_STATE_HALT;
2904
2905 /* In case the HCD restarted the timer, stop it again. */
2906 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2907 del_timer_sync(&hcd->rh_timer);
2908
2909 if (usb_hcd_is_primary_hcd(hcd)) {
2910 if (hcd->irq > 0)
2911 free_irq(hcd->irq, hcd);
2912 }
2913
2914 usb_deregister_bus(&hcd->self);
2915 hcd_buffer_destroy(hcd);
2916
2917 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->phy) {
2918 phy_power_off(hcd->phy);
2919 phy_exit(hcd->phy);
2920 phy_put(hcd->phy);
2921 hcd->phy = NULL;
2922 }
2923 if (hcd->remove_phy && hcd->usb_phy) {
2924 usb_phy_shutdown(hcd->usb_phy);
2925 usb_put_phy(hcd->usb_phy);
2926 hcd->usb_phy = NULL;
2927 }
2928
2929 usb_put_invalidate_rhdev(hcd);
2930 hcd->flags = 0;
2931 }
2932 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2933
2934 void
usb_hcd_platform_shutdown(struct platform_device * dev)2935 usb_hcd_platform_shutdown(struct platform_device *dev)
2936 {
2937 struct usb_hcd *hcd = platform_get_drvdata(dev);
2938
2939 if (hcd->driver->shutdown)
2940 hcd->driver->shutdown(hcd);
2941 }
2942 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2943
2944 /*-------------------------------------------------------------------------*/
2945
2946 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2947
2948 struct usb_mon_operations *mon_ops;
2949
2950 /*
2951 * The registration is unlocked.
2952 * We do it this way because we do not want to lock in hot paths.
2953 *
2954 * Notice that the code is minimally error-proof. Because usbmon needs
2955 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2956 */
2957
usb_mon_register(struct usb_mon_operations * ops)2958 int usb_mon_register (struct usb_mon_operations *ops)
2959 {
2960
2961 if (mon_ops)
2962 return -EBUSY;
2963
2964 mon_ops = ops;
2965 mb();
2966 return 0;
2967 }
2968 EXPORT_SYMBOL_GPL (usb_mon_register);
2969
usb_mon_deregister(void)2970 void usb_mon_deregister (void)
2971 {
2972
2973 if (mon_ops == NULL) {
2974 printk(KERN_ERR "USB: monitor was not registered\n");
2975 return;
2976 }
2977 mon_ops = NULL;
2978 mb();
2979 }
2980 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2981
2982 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
2983