1 // SPDX-License-Identifier: GPL-2.0
2 /**
3 * udc.c - Core UDC Framework
4 *
5 * Copyright (C) 2010 Texas Instruments
6 * Author: Felipe Balbi <balbi@ti.com>
7 */
8
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/device.h>
12 #include <linux/list.h>
13 #include <linux/err.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/sched/task_stack.h>
16 #include <linux/workqueue.h>
17
18 #include <linux/usb/ch9.h>
19 #include <linux/usb/gadget.h>
20 #include <linux/usb.h>
21
22 #include "trace.h"
23
24 /**
25 * struct usb_udc - describes one usb device controller
26 * @driver - the gadget driver pointer. For use by the class code
27 * @dev - the child device to the actual controller
28 * @gadget - the gadget. For use by the class code
29 * @list - for use by the udc class driver
30 * @vbus - for udcs who care about vbus status, this value is real vbus status;
31 * for udcs who do not care about vbus status, this value is always true
32 *
33 * This represents the internal data structure which is used by the UDC-class
34 * to hold information about udc driver and gadget together.
35 */
36 struct usb_udc {
37 struct usb_gadget_driver *driver;
38 struct usb_gadget *gadget;
39 struct device dev;
40 struct list_head list;
41 bool vbus;
42 };
43
44 static struct class *udc_class;
45 static LIST_HEAD(udc_list);
46 static LIST_HEAD(gadget_driver_pending_list);
47 static DEFINE_MUTEX(udc_lock);
48
49 static int udc_bind_to_driver(struct usb_udc *udc,
50 struct usb_gadget_driver *driver);
51
52 /* ------------------------------------------------------------------------- */
53
54 /**
55 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
56 * @ep:the endpoint being configured
57 * @maxpacket_limit:value of maximum packet size limit
58 *
59 * This function should be used only in UDC drivers to initialize endpoint
60 * (usually in probe function).
61 */
62 void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
63 unsigned maxpacket_limit)
64 {
65 ep->maxpacket_limit = maxpacket_limit;
66 ep->maxpacket = maxpacket_limit;
67
68 trace_usb_ep_set_maxpacket_limit(ep, 0);
69 }
70 EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
71
72 /**
73 * usb_ep_enable - configure endpoint, making it usable
74 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
75 * drivers discover endpoints through the ep_list of a usb_gadget.
76 *
77 * When configurations are set, or when interface settings change, the driver
78 * will enable or disable the relevant endpoints. while it is enabled, an
79 * endpoint may be used for i/o until the driver receives a disconnect() from
80 * the host or until the endpoint is disabled.
81 *
82 * the ep0 implementation (which calls this routine) must ensure that the
83 * hardware capabilities of each endpoint match the descriptor provided
84 * for it. for example, an endpoint named "ep2in-bulk" would be usable
85 * for interrupt transfers as well as bulk, but it likely couldn't be used
86 * for iso transfers or for endpoint 14. some endpoints are fully
87 * configurable, with more generic names like "ep-a". (remember that for
88 * USB, "in" means "towards the USB master".)
89 *
90 * This routine must be called in process context.
91 *
92 * returns zero, or a negative error code.
93 */
94 int usb_ep_enable(struct usb_ep *ep)
95 {
96 int ret = 0;
97
98 if (ep->enabled)
99 goto out;
100
101 /* UDC drivers can't handle endpoints with maxpacket size 0 */
102 if (usb_endpoint_maxp(ep->desc) == 0) {
103 /*
104 * We should log an error message here, but we can't call
105 * dev_err() because there's no way to find the gadget
106 * given only ep.
107 */
108 ret = -EINVAL;
109 goto out;
110 }
111
112 ret = ep->ops->enable(ep, ep->desc);
113 if (ret)
114 goto out;
115
116 ep->enabled = true;
117
118 out:
119 trace_usb_ep_enable(ep, ret);
120
121 return ret;
122 }
123 EXPORT_SYMBOL_GPL(usb_ep_enable);
124
125 /**
126 * usb_ep_disable - endpoint is no longer usable
127 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
128 *
129 * no other task may be using this endpoint when this is called.
130 * any pending and uncompleted requests will complete with status
131 * indicating disconnect (-ESHUTDOWN) before this call returns.
132 * gadget drivers must call usb_ep_enable() again before queueing
133 * requests to the endpoint.
134 *
135 * This routine must be called in process context.
136 *
137 * returns zero, or a negative error code.
138 */
139 int usb_ep_disable(struct usb_ep *ep)
140 {
141 int ret = 0;
142
143 if (!ep->enabled)
144 goto out;
145
146 ret = ep->ops->disable(ep);
147 if (ret)
148 goto out;
149
150 ep->enabled = false;
151
152 out:
153 trace_usb_ep_disable(ep, ret);
154
155 return ret;
156 }
157 EXPORT_SYMBOL_GPL(usb_ep_disable);
158
159 /**
160 * usb_ep_alloc_request - allocate a request object to use with this endpoint
161 * @ep:the endpoint to be used with with the request
162 * @gfp_flags:GFP_* flags to use
163 *
164 * Request objects must be allocated with this call, since they normally
165 * need controller-specific setup and may even need endpoint-specific
166 * resources such as allocation of DMA descriptors.
167 * Requests may be submitted with usb_ep_queue(), and receive a single
168 * completion callback. Free requests with usb_ep_free_request(), when
169 * they are no longer needed.
170 *
171 * Returns the request, or null if one could not be allocated.
172 */
173 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
174 gfp_t gfp_flags)
175 {
176 struct usb_request *req = NULL;
177
178 req = ep->ops->alloc_request(ep, gfp_flags);
179
180 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
181
182 return req;
183 }
184 EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
185
186 /**
187 * usb_ep_free_request - frees a request object
188 * @ep:the endpoint associated with the request
189 * @req:the request being freed
190 *
191 * Reverses the effect of usb_ep_alloc_request().
192 * Caller guarantees the request is not queued, and that it will
193 * no longer be requeued (or otherwise used).
194 */
195 void usb_ep_free_request(struct usb_ep *ep,
196 struct usb_request *req)
197 {
198 trace_usb_ep_free_request(ep, req, 0);
199 ep->ops->free_request(ep, req);
200 }
201 EXPORT_SYMBOL_GPL(usb_ep_free_request);
202
203 /**
204 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
205 * @ep:the endpoint associated with the request
206 * @req:the request being submitted
207 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
208 * pre-allocate all necessary memory with the request.
209 *
210 * This tells the device controller to perform the specified request through
211 * that endpoint (reading or writing a buffer). When the request completes,
212 * including being canceled by usb_ep_dequeue(), the request's completion
213 * routine is called to return the request to the driver. Any endpoint
214 * (except control endpoints like ep0) may have more than one transfer
215 * request queued; they complete in FIFO order. Once a gadget driver
216 * submits a request, that request may not be examined or modified until it
217 * is given back to that driver through the completion callback.
218 *
219 * Each request is turned into one or more packets. The controller driver
220 * never merges adjacent requests into the same packet. OUT transfers
221 * will sometimes use data that's already buffered in the hardware.
222 * Drivers can rely on the fact that the first byte of the request's buffer
223 * always corresponds to the first byte of some USB packet, for both
224 * IN and OUT transfers.
225 *
226 * Bulk endpoints can queue any amount of data; the transfer is packetized
227 * automatically. The last packet will be short if the request doesn't fill it
228 * out completely. Zero length packets (ZLPs) should be avoided in portable
229 * protocols since not all usb hardware can successfully handle zero length
230 * packets. (ZLPs may be explicitly written, and may be implicitly written if
231 * the request 'zero' flag is set.) Bulk endpoints may also be used
232 * for interrupt transfers; but the reverse is not true, and some endpoints
233 * won't support every interrupt transfer. (Such as 768 byte packets.)
234 *
235 * Interrupt-only endpoints are less functional than bulk endpoints, for
236 * example by not supporting queueing or not handling buffers that are
237 * larger than the endpoint's maxpacket size. They may also treat data
238 * toggle differently.
239 *
240 * Control endpoints ... after getting a setup() callback, the driver queues
241 * one response (even if it would be zero length). That enables the
242 * status ack, after transferring data as specified in the response. Setup
243 * functions may return negative error codes to generate protocol stalls.
244 * (Note that some USB device controllers disallow protocol stall responses
245 * in some cases.) When control responses are deferred (the response is
246 * written after the setup callback returns), then usb_ep_set_halt() may be
247 * used on ep0 to trigger protocol stalls. Depending on the controller,
248 * it may not be possible to trigger a status-stage protocol stall when the
249 * data stage is over, that is, from within the response's completion
250 * routine.
251 *
252 * For periodic endpoints, like interrupt or isochronous ones, the usb host
253 * arranges to poll once per interval, and the gadget driver usually will
254 * have queued some data to transfer at that time.
255 *
256 * Note that @req's ->complete() callback must never be called from
257 * within usb_ep_queue() as that can create deadlock situations.
258 *
259 * This routine may be called in interrupt context.
260 *
261 * Returns zero, or a negative error code. Endpoints that are not enabled
262 * report errors; errors will also be
263 * reported when the usb peripheral is disconnected.
264 *
265 * If and only if @req is successfully queued (the return value is zero),
266 * @req->complete() will be called exactly once, when the Gadget core and
267 * UDC are finished with the request. When the completion function is called,
268 * control of the request is returned to the device driver which submitted it.
269 * The completion handler may then immediately free or reuse @req.
270 */
271 int usb_ep_queue(struct usb_ep *ep,
272 struct usb_request *req, gfp_t gfp_flags)
273 {
274 int ret = 0;
275
276 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
277 ret = -ESHUTDOWN;
278 goto out;
279 }
280
281 ret = ep->ops->queue(ep, req, gfp_flags);
282
283 out:
284 trace_usb_ep_queue(ep, req, ret);
285
286 return ret;
287 }
288 EXPORT_SYMBOL_GPL(usb_ep_queue);
289
290 /**
291 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
292 * @ep:the endpoint associated with the request
293 * @req:the request being canceled
294 *
295 * If the request is still active on the endpoint, it is dequeued and
296 * eventually its completion routine is called (with status -ECONNRESET);
297 * else a negative error code is returned. This routine is asynchronous,
298 * that is, it may return before the completion routine runs.
299 *
300 * Note that some hardware can't clear out write fifos (to unlink the request
301 * at the head of the queue) except as part of disconnecting from usb. Such
302 * restrictions prevent drivers from supporting configuration changes,
303 * even to configuration zero (a "chapter 9" requirement).
304 *
305 * This routine may be called in interrupt context.
306 */
307 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
308 {
309 int ret;
310
311 ret = ep->ops->dequeue(ep, req);
312 trace_usb_ep_dequeue(ep, req, ret);
313
314 return ret;
315 }
316 EXPORT_SYMBOL_GPL(usb_ep_dequeue);
317
318 /**
319 * usb_ep_set_halt - sets the endpoint halt feature.
320 * @ep: the non-isochronous endpoint being stalled
321 *
322 * Use this to stall an endpoint, perhaps as an error report.
323 * Except for control endpoints,
324 * the endpoint stays halted (will not stream any data) until the host
325 * clears this feature; drivers may need to empty the endpoint's request
326 * queue first, to make sure no inappropriate transfers happen.
327 *
328 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
329 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
330 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
331 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
332 *
333 * This routine may be called in interrupt context.
334 *
335 * Returns zero, or a negative error code. On success, this call sets
336 * underlying hardware state that blocks data transfers.
337 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
338 * transfer requests are still queued, or if the controller hardware
339 * (usually a FIFO) still holds bytes that the host hasn't collected.
340 */
341 int usb_ep_set_halt(struct usb_ep *ep)
342 {
343 int ret;
344
345 ret = ep->ops->set_halt(ep, 1);
346 trace_usb_ep_set_halt(ep, ret);
347
348 return ret;
349 }
350 EXPORT_SYMBOL_GPL(usb_ep_set_halt);
351
352 /**
353 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
354 * @ep:the bulk or interrupt endpoint being reset
355 *
356 * Use this when responding to the standard usb "set interface" request,
357 * for endpoints that aren't reconfigured, after clearing any other state
358 * in the endpoint's i/o queue.
359 *
360 * This routine may be called in interrupt context.
361 *
362 * Returns zero, or a negative error code. On success, this call clears
363 * the underlying hardware state reflecting endpoint halt and data toggle.
364 * Note that some hardware can't support this request (like pxa2xx_udc),
365 * and accordingly can't correctly implement interface altsettings.
366 */
367 int usb_ep_clear_halt(struct usb_ep *ep)
368 {
369 int ret;
370
371 ret = ep->ops->set_halt(ep, 0);
372 trace_usb_ep_clear_halt(ep, ret);
373
374 return ret;
375 }
376 EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
377
378 /**
379 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
380 * @ep: the endpoint being wedged
381 *
382 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
383 * requests. If the gadget driver clears the halt status, it will
384 * automatically unwedge the endpoint.
385 *
386 * This routine may be called in interrupt context.
387 *
388 * Returns zero on success, else negative errno.
389 */
390 int usb_ep_set_wedge(struct usb_ep *ep)
391 {
392 int ret;
393
394 if (ep->ops->set_wedge)
395 ret = ep->ops->set_wedge(ep);
396 else
397 ret = ep->ops->set_halt(ep, 1);
398
399 trace_usb_ep_set_wedge(ep, ret);
400
401 return ret;
402 }
403 EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
404
405 /**
406 * usb_ep_fifo_status - returns number of bytes in fifo, or error
407 * @ep: the endpoint whose fifo status is being checked.
408 *
409 * FIFO endpoints may have "unclaimed data" in them in certain cases,
410 * such as after aborted transfers. Hosts may not have collected all
411 * the IN data written by the gadget driver (and reported by a request
412 * completion). The gadget driver may not have collected all the data
413 * written OUT to it by the host. Drivers that need precise handling for
414 * fault reporting or recovery may need to use this call.
415 *
416 * This routine may be called in interrupt context.
417 *
418 * This returns the number of such bytes in the fifo, or a negative
419 * errno if the endpoint doesn't use a FIFO or doesn't support such
420 * precise handling.
421 */
422 int usb_ep_fifo_status(struct usb_ep *ep)
423 {
424 int ret;
425
426 if (ep->ops->fifo_status)
427 ret = ep->ops->fifo_status(ep);
428 else
429 ret = -EOPNOTSUPP;
430
431 trace_usb_ep_fifo_status(ep, ret);
432
433 return ret;
434 }
435 EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
436
437 /**
438 * usb_ep_fifo_flush - flushes contents of a fifo
439 * @ep: the endpoint whose fifo is being flushed.
440 *
441 * This call may be used to flush the "unclaimed data" that may exist in
442 * an endpoint fifo after abnormal transaction terminations. The call
443 * must never be used except when endpoint is not being used for any
444 * protocol translation.
445 *
446 * This routine may be called in interrupt context.
447 */
448 void usb_ep_fifo_flush(struct usb_ep *ep)
449 {
450 if (ep->ops->fifo_flush)
451 ep->ops->fifo_flush(ep);
452
453 trace_usb_ep_fifo_flush(ep, 0);
454 }
455 EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
456
457 /* ------------------------------------------------------------------------- */
458
459 /**
460 * usb_gadget_frame_number - returns the current frame number
461 * @gadget: controller that reports the frame number
462 *
463 * Returns the usb frame number, normally eleven bits from a SOF packet,
464 * or negative errno if this device doesn't support this capability.
465 */
466 int usb_gadget_frame_number(struct usb_gadget *gadget)
467 {
468 int ret;
469
470 ret = gadget->ops->get_frame(gadget);
471
472 trace_usb_gadget_frame_number(gadget, ret);
473
474 return ret;
475 }
476 EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
477
478 /**
479 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
480 * @gadget: controller used to wake up the host
481 *
482 * Returns zero on success, else negative error code if the hardware
483 * doesn't support such attempts, or its support has not been enabled
484 * by the usb host. Drivers must return device descriptors that report
485 * their ability to support this, or hosts won't enable it.
486 *
487 * This may also try to use SRP to wake the host and start enumeration,
488 * even if OTG isn't otherwise in use. OTG devices may also start
489 * remote wakeup even when hosts don't explicitly enable it.
490 */
491 int usb_gadget_wakeup(struct usb_gadget *gadget)
492 {
493 int ret = 0;
494
495 if (!gadget->ops->wakeup) {
496 ret = -EOPNOTSUPP;
497 goto out;
498 }
499
500 ret = gadget->ops->wakeup(gadget);
501
502 out:
503 trace_usb_gadget_wakeup(gadget, ret);
504
505 return ret;
506 }
507 EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
508
509 /**
510 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
511 * @gadget:the device being declared as self-powered
512 *
513 * this affects the device status reported by the hardware driver
514 * to reflect that it now has a local power supply.
515 *
516 * returns zero on success, else negative errno.
517 */
518 int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
519 {
520 int ret = 0;
521
522 if (!gadget->ops->set_selfpowered) {
523 ret = -EOPNOTSUPP;
524 goto out;
525 }
526
527 ret = gadget->ops->set_selfpowered(gadget, 1);
528
529 out:
530 trace_usb_gadget_set_selfpowered(gadget, ret);
531
532 return ret;
533 }
534 EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
535
536 /**
537 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
538 * @gadget:the device being declared as bus-powered
539 *
540 * this affects the device status reported by the hardware driver.
541 * some hardware may not support bus-powered operation, in which
542 * case this feature's value can never change.
543 *
544 * returns zero on success, else negative errno.
545 */
546 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
547 {
548 int ret = 0;
549
550 if (!gadget->ops->set_selfpowered) {
551 ret = -EOPNOTSUPP;
552 goto out;
553 }
554
555 ret = gadget->ops->set_selfpowered(gadget, 0);
556
557 out:
558 trace_usb_gadget_clear_selfpowered(gadget, ret);
559
560 return ret;
561 }
562 EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
563
564 /**
565 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
566 * @gadget:The device which now has VBUS power.
567 * Context: can sleep
568 *
569 * This call is used by a driver for an external transceiver (or GPIO)
570 * that detects a VBUS power session starting. Common responses include
571 * resuming the controller, activating the D+ (or D-) pullup to let the
572 * host detect that a USB device is attached, and starting to draw power
573 * (8mA or possibly more, especially after SET_CONFIGURATION).
574 *
575 * Returns zero on success, else negative errno.
576 */
577 int usb_gadget_vbus_connect(struct usb_gadget *gadget)
578 {
579 int ret = 0;
580
581 if (!gadget->ops->vbus_session) {
582 ret = -EOPNOTSUPP;
583 goto out;
584 }
585
586 ret = gadget->ops->vbus_session(gadget, 1);
587
588 out:
589 trace_usb_gadget_vbus_connect(gadget, ret);
590
591 return ret;
592 }
593 EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
594
595 /**
596 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
597 * @gadget:The device whose VBUS usage is being described
598 * @mA:How much current to draw, in milliAmperes. This should be twice
599 * the value listed in the configuration descriptor bMaxPower field.
600 *
601 * This call is used by gadget drivers during SET_CONFIGURATION calls,
602 * reporting how much power the device may consume. For example, this
603 * could affect how quickly batteries are recharged.
604 *
605 * Returns zero on success, else negative errno.
606 */
607 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
608 {
609 int ret = 0;
610
611 if (!gadget->ops->vbus_draw) {
612 ret = -EOPNOTSUPP;
613 goto out;
614 }
615
616 ret = gadget->ops->vbus_draw(gadget, mA);
617 if (!ret)
618 gadget->mA = mA;
619
620 out:
621 trace_usb_gadget_vbus_draw(gadget, ret);
622
623 return ret;
624 }
625 EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
626
627 /**
628 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
629 * @gadget:the device whose VBUS supply is being described
630 * Context: can sleep
631 *
632 * This call is used by a driver for an external transceiver (or GPIO)
633 * that detects a VBUS power session ending. Common responses include
634 * reversing everything done in usb_gadget_vbus_connect().
635 *
636 * Returns zero on success, else negative errno.
637 */
638 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
639 {
640 int ret = 0;
641
642 if (!gadget->ops->vbus_session) {
643 ret = -EOPNOTSUPP;
644 goto out;
645 }
646
647 ret = gadget->ops->vbus_session(gadget, 0);
648
649 out:
650 trace_usb_gadget_vbus_disconnect(gadget, ret);
651
652 return ret;
653 }
654 EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
655
656 /**
657 * usb_gadget_connect - software-controlled connect to USB host
658 * @gadget:the peripheral being connected
659 *
660 * Enables the D+ (or potentially D-) pullup. The host will start
661 * enumerating this gadget when the pullup is active and a VBUS session
662 * is active (the link is powered). This pullup is always enabled unless
663 * usb_gadget_disconnect() has been used to disable it.
664 *
665 * Returns zero on success, else negative errno.
666 */
667 int usb_gadget_connect(struct usb_gadget *gadget)
668 {
669 int ret = 0;
670
671 if (!gadget->ops->pullup) {
672 ret = -EOPNOTSUPP;
673 goto out;
674 }
675
676 if (gadget->deactivated) {
677 /*
678 * If gadget is deactivated we only save new state.
679 * Gadget will be connected automatically after activation.
680 */
681 gadget->connected = true;
682 goto out;
683 }
684
685 ret = gadget->ops->pullup(gadget, 1);
686 if (!ret)
687 gadget->connected = 1;
688
689 out:
690 trace_usb_gadget_connect(gadget, ret);
691
692 return ret;
693 }
694 EXPORT_SYMBOL_GPL(usb_gadget_connect);
695
696 /**
697 * usb_gadget_disconnect - software-controlled disconnect from USB host
698 * @gadget:the peripheral being disconnected
699 *
700 * Disables the D+ (or potentially D-) pullup, which the host may see
701 * as a disconnect (when a VBUS session is active). Not all systems
702 * support software pullup controls.
703 *
704 * Following a successful disconnect, invoke the ->disconnect() callback
705 * for the current gadget driver so that UDC drivers don't need to.
706 *
707 * Returns zero on success, else negative errno.
708 */
709 int usb_gadget_disconnect(struct usb_gadget *gadget)
710 {
711 int ret = 0;
712
713 if (!gadget->ops->pullup) {
714 ret = -EOPNOTSUPP;
715 goto out;
716 }
717
718 if (gadget->deactivated) {
719 /*
720 * If gadget is deactivated we only save new state.
721 * Gadget will stay disconnected after activation.
722 */
723 gadget->connected = false;
724 goto out;
725 }
726
727 ret = gadget->ops->pullup(gadget, 0);
728 if (!ret) {
729 gadget->connected = 0;
730 gadget->udc->driver->disconnect(gadget);
731 }
732
733 out:
734 trace_usb_gadget_disconnect(gadget, ret);
735
736 return ret;
737 }
738 EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
739
740 /**
741 * usb_gadget_deactivate - deactivate function which is not ready to work
742 * @gadget: the peripheral being deactivated
743 *
744 * This routine may be used during the gadget driver bind() call to prevent
745 * the peripheral from ever being visible to the USB host, unless later
746 * usb_gadget_activate() is called. For example, user mode components may
747 * need to be activated before the system can talk to hosts.
748 *
749 * Returns zero on success, else negative errno.
750 */
751 int usb_gadget_deactivate(struct usb_gadget *gadget)
752 {
753 int ret = 0;
754
755 if (gadget->deactivated)
756 goto out;
757
758 if (gadget->connected) {
759 ret = usb_gadget_disconnect(gadget);
760 if (ret)
761 goto out;
762
763 /*
764 * If gadget was being connected before deactivation, we want
765 * to reconnect it in usb_gadget_activate().
766 */
767 gadget->connected = true;
768 }
769 gadget->deactivated = true;
770
771 out:
772 trace_usb_gadget_deactivate(gadget, ret);
773
774 return ret;
775 }
776 EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
777
778 /**
779 * usb_gadget_activate - activate function which is not ready to work
780 * @gadget: the peripheral being activated
781 *
782 * This routine activates gadget which was previously deactivated with
783 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
784 *
785 * Returns zero on success, else negative errno.
786 */
787 int usb_gadget_activate(struct usb_gadget *gadget)
788 {
789 int ret = 0;
790
791 if (!gadget->deactivated)
792 goto out;
793
794 gadget->deactivated = false;
795
796 /*
797 * If gadget has been connected before deactivation, or became connected
798 * while it was being deactivated, we call usb_gadget_connect().
799 */
800 if (gadget->connected)
801 ret = usb_gadget_connect(gadget);
802
803 out:
804 trace_usb_gadget_activate(gadget, ret);
805
806 return ret;
807 }
808 EXPORT_SYMBOL_GPL(usb_gadget_activate);
809
810 /* ------------------------------------------------------------------------- */
811
812 #ifdef CONFIG_HAS_DMA
813
814 int usb_gadget_map_request_by_dev(struct device *dev,
815 struct usb_request *req, int is_in)
816 {
817 if (req->length == 0)
818 return 0;
819
820 if (req->num_sgs) {
821 int mapped;
822
823 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
824 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
825 if (mapped == 0) {
826 dev_err(dev, "failed to map SGs\n");
827 return -EFAULT;
828 }
829
830 req->num_mapped_sgs = mapped;
831 } else {
832 if (is_vmalloc_addr(req->buf)) {
833 dev_err(dev, "buffer is not dma capable\n");
834 return -EFAULT;
835 } else if (object_is_on_stack(req->buf)) {
836 dev_err(dev, "buffer is on stack\n");
837 return -EFAULT;
838 }
839
840 req->dma = dma_map_single(dev, req->buf, req->length,
841 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
842
843 if (dma_mapping_error(dev, req->dma)) {
844 dev_err(dev, "failed to map buffer\n");
845 return -EFAULT;
846 }
847
848 req->dma_mapped = 1;
849 }
850
851 return 0;
852 }
853 EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
854
855 int usb_gadget_map_request(struct usb_gadget *gadget,
856 struct usb_request *req, int is_in)
857 {
858 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
859 }
860 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
861
862 void usb_gadget_unmap_request_by_dev(struct device *dev,
863 struct usb_request *req, int is_in)
864 {
865 if (req->length == 0)
866 return;
867
868 if (req->num_mapped_sgs) {
869 dma_unmap_sg(dev, req->sg, req->num_sgs,
870 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
871
872 req->num_mapped_sgs = 0;
873 } else if (req->dma_mapped) {
874 dma_unmap_single(dev, req->dma, req->length,
875 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
876 req->dma_mapped = 0;
877 }
878 }
879 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
880
881 void usb_gadget_unmap_request(struct usb_gadget *gadget,
882 struct usb_request *req, int is_in)
883 {
884 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
885 }
886 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
887
888 #endif /* CONFIG_HAS_DMA */
889
890 /* ------------------------------------------------------------------------- */
891
892 /**
893 * usb_gadget_giveback_request - give the request back to the gadget layer
894 * Context: in_interrupt()
895 *
896 * This is called by device controller drivers in order to return the
897 * completed request back to the gadget layer.
898 */
899 void usb_gadget_giveback_request(struct usb_ep *ep,
900 struct usb_request *req)
901 {
902 if (likely(req->status == 0))
903 usb_led_activity(USB_LED_EVENT_GADGET);
904
905 trace_usb_gadget_giveback_request(ep, req, 0);
906
907 req->complete(ep, req);
908 }
909 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
910
911 /* ------------------------------------------------------------------------- */
912
913 /**
914 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
915 * in second parameter or NULL if searched endpoint not found
916 * @g: controller to check for quirk
917 * @name: name of searched endpoint
918 */
919 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
920 {
921 struct usb_ep *ep;
922
923 gadget_for_each_ep(ep, g) {
924 if (!strcmp(ep->name, name))
925 return ep;
926 }
927
928 return NULL;
929 }
930 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
931
932 /* ------------------------------------------------------------------------- */
933
934 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
935 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
936 struct usb_ss_ep_comp_descriptor *ep_comp)
937 {
938 u8 type;
939 u16 max;
940 int num_req_streams = 0;
941
942 /* endpoint already claimed? */
943 if (ep->claimed)
944 return 0;
945
946 type = usb_endpoint_type(desc);
947 max = usb_endpoint_maxp(desc);
948
949 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
950 return 0;
951 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
952 return 0;
953
954 if (max > ep->maxpacket_limit)
955 return 0;
956
957 /* "high bandwidth" works only at high speed */
958 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
959 return 0;
960
961 switch (type) {
962 case USB_ENDPOINT_XFER_CONTROL:
963 /* only support ep0 for portable CONTROL traffic */
964 return 0;
965 case USB_ENDPOINT_XFER_ISOC:
966 if (!ep->caps.type_iso)
967 return 0;
968 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
969 if (!gadget_is_dualspeed(gadget) && max > 1023)
970 return 0;
971 break;
972 case USB_ENDPOINT_XFER_BULK:
973 if (!ep->caps.type_bulk)
974 return 0;
975 if (ep_comp && gadget_is_superspeed(gadget)) {
976 /* Get the number of required streams from the
977 * EP companion descriptor and see if the EP
978 * matches it
979 */
980 num_req_streams = ep_comp->bmAttributes & 0x1f;
981 if (num_req_streams > ep->max_streams)
982 return 0;
983 }
984 break;
985 case USB_ENDPOINT_XFER_INT:
986 /* Bulk endpoints handle interrupt transfers,
987 * except the toggle-quirky iso-synch kind
988 */
989 if (!ep->caps.type_int && !ep->caps.type_bulk)
990 return 0;
991 /* INT: limit 64 bytes full speed, 1024 high/super speed */
992 if (!gadget_is_dualspeed(gadget) && max > 64)
993 return 0;
994 break;
995 }
996
997 return 1;
998 }
999 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
1000
1001 /* ------------------------------------------------------------------------- */
1002
1003 static void usb_gadget_state_work(struct work_struct *work)
1004 {
1005 struct usb_gadget *gadget = work_to_gadget(work);
1006 struct usb_udc *udc = gadget->udc;
1007
1008 if (udc)
1009 sysfs_notify(&udc->dev.kobj, NULL, "state");
1010 }
1011
1012 void usb_gadget_set_state(struct usb_gadget *gadget,
1013 enum usb_device_state state)
1014 {
1015 gadget->state = state;
1016 schedule_work(&gadget->work);
1017 }
1018 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
1019
1020 /* ------------------------------------------------------------------------- */
1021
1022 static void usb_udc_connect_control(struct usb_udc *udc)
1023 {
1024 if (udc->vbus)
1025 usb_gadget_connect(udc->gadget);
1026 else
1027 usb_gadget_disconnect(udc->gadget);
1028 }
1029
1030 /**
1031 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1032 * connect or disconnect gadget
1033 * @gadget: The gadget which vbus change occurs
1034 * @status: The vbus status
1035 *
1036 * The udc driver calls it when it wants to connect or disconnect gadget
1037 * according to vbus status.
1038 */
1039 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1040 {
1041 struct usb_udc *udc = gadget->udc;
1042
1043 if (udc) {
1044 udc->vbus = status;
1045 usb_udc_connect_control(udc);
1046 }
1047 }
1048 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1049
1050 /**
1051 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1052 * @gadget: The gadget which bus reset occurs
1053 * @driver: The gadget driver we want to notify
1054 *
1055 * If the udc driver has bus reset handler, it needs to call this when the bus
1056 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1057 * well as updates gadget state.
1058 */
1059 void usb_gadget_udc_reset(struct usb_gadget *gadget,
1060 struct usb_gadget_driver *driver)
1061 {
1062 driver->reset(gadget);
1063 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1064 }
1065 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1066
1067 /**
1068 * usb_gadget_udc_start - tells usb device controller to start up
1069 * @udc: The UDC to be started
1070 *
1071 * This call is issued by the UDC Class driver when it's about
1072 * to register a gadget driver to the device controller, before
1073 * calling gadget driver's bind() method.
1074 *
1075 * It allows the controller to be powered off until strictly
1076 * necessary to have it powered on.
1077 *
1078 * Returns zero on success, else negative errno.
1079 */
1080 static inline int usb_gadget_udc_start(struct usb_udc *udc)
1081 {
1082 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1083 }
1084
1085 /**
1086 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
1087 * @gadget: The device we want to stop activity
1088 * @driver: The driver to unbind from @gadget
1089 *
1090 * This call is issued by the UDC Class driver after calling
1091 * gadget driver's unbind() method.
1092 *
1093 * The details are implementation specific, but it can go as
1094 * far as powering off UDC completely and disable its data
1095 * line pullups.
1096 */
1097 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
1098 {
1099 udc->gadget->ops->udc_stop(udc->gadget);
1100 }
1101
1102 /**
1103 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1104 * current driver
1105 * @udc: The device we want to set maximum speed
1106 * @speed: The maximum speed to allowed to run
1107 *
1108 * This call is issued by the UDC Class driver before calling
1109 * usb_gadget_udc_start() in order to make sure that we don't try to
1110 * connect on speeds the gadget driver doesn't support.
1111 */
1112 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1113 enum usb_device_speed speed)
1114 {
1115 if (udc->gadget->ops->udc_set_speed) {
1116 enum usb_device_speed s;
1117
1118 s = min(speed, udc->gadget->max_speed);
1119 udc->gadget->ops->udc_set_speed(udc->gadget, s);
1120 }
1121 }
1122
1123 /**
1124 * usb_udc_release - release the usb_udc struct
1125 * @dev: the dev member within usb_udc
1126 *
1127 * This is called by driver's core in order to free memory once the last
1128 * reference is released.
1129 */
1130 static void usb_udc_release(struct device *dev)
1131 {
1132 struct usb_udc *udc;
1133
1134 udc = container_of(dev, struct usb_udc, dev);
1135 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1136 kfree(udc);
1137 }
1138
1139 static const struct attribute_group *usb_udc_attr_groups[];
1140
1141 static void usb_udc_nop_release(struct device *dev)
1142 {
1143 dev_vdbg(dev, "%s\n", __func__);
1144 }
1145
1146 /* should be called with udc_lock held */
1147 static int check_pending_gadget_drivers(struct usb_udc *udc)
1148 {
1149 struct usb_gadget_driver *driver;
1150 int ret = 0;
1151
1152 list_for_each_entry(driver, &gadget_driver_pending_list, pending)
1153 if (!driver->udc_name || strcmp(driver->udc_name,
1154 dev_name(&udc->dev)) == 0) {
1155 ret = udc_bind_to_driver(udc, driver);
1156 if (ret != -EPROBE_DEFER)
1157 list_del_init(&driver->pending);
1158 break;
1159 }
1160
1161 return ret;
1162 }
1163
1164 /**
1165 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1166 * @parent: the parent device to this udc. Usually the controller driver's
1167 * device.
1168 * @gadget: the gadget to be added to the list.
1169 * @release: a gadget release function.
1170 *
1171 * Returns zero on success, negative errno otherwise.
1172 * Calls the gadget release function in the latter case.
1173 */
1174 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1175 void (*release)(struct device *dev))
1176 {
1177 struct usb_udc *udc;
1178 int ret = -ENOMEM;
1179
1180 dev_set_name(&gadget->dev, "gadget");
1181 INIT_WORK(&gadget->work, usb_gadget_state_work);
1182 gadget->dev.parent = parent;
1183
1184 if (release)
1185 gadget->dev.release = release;
1186 else
1187 gadget->dev.release = usb_udc_nop_release;
1188
1189 device_initialize(&gadget->dev);
1190
1191 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1192 if (!udc)
1193 goto err_put_gadget;
1194
1195 device_initialize(&udc->dev);
1196 udc->dev.release = usb_udc_release;
1197 udc->dev.class = udc_class;
1198 udc->dev.groups = usb_udc_attr_groups;
1199 udc->dev.parent = parent;
1200 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
1201 if (ret)
1202 goto err_put_udc;
1203
1204 ret = device_add(&gadget->dev);
1205 if (ret)
1206 goto err_put_udc;
1207
1208 udc->gadget = gadget;
1209 gadget->udc = udc;
1210
1211 mutex_lock(&udc_lock);
1212 list_add_tail(&udc->list, &udc_list);
1213
1214 ret = device_add(&udc->dev);
1215 if (ret)
1216 goto err_unlist_udc;
1217
1218 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1219 udc->vbus = true;
1220
1221 /* pick up one of pending gadget drivers */
1222 ret = check_pending_gadget_drivers(udc);
1223 if (ret)
1224 goto err_del_udc;
1225
1226 mutex_unlock(&udc_lock);
1227
1228 return 0;
1229
1230 err_del_udc:
1231 device_del(&udc->dev);
1232
1233 err_unlist_udc:
1234 list_del(&udc->list);
1235 mutex_unlock(&udc_lock);
1236
1237 device_del(&gadget->dev);
1238
1239 err_put_udc:
1240 put_device(&udc->dev);
1241
1242 err_put_gadget:
1243 put_device(&gadget->dev);
1244 return ret;
1245 }
1246 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1247
1248 /**
1249 * usb_get_gadget_udc_name - get the name of the first UDC controller
1250 * This functions returns the name of the first UDC controller in the system.
1251 * Please note that this interface is usefull only for legacy drivers which
1252 * assume that there is only one UDC controller in the system and they need to
1253 * get its name before initialization. There is no guarantee that the UDC
1254 * of the returned name will be still available, when gadget driver registers
1255 * itself.
1256 *
1257 * Returns pointer to string with UDC controller name on success, NULL
1258 * otherwise. Caller should kfree() returned string.
1259 */
1260 char *usb_get_gadget_udc_name(void)
1261 {
1262 struct usb_udc *udc;
1263 char *name = NULL;
1264
1265 /* For now we take the first available UDC */
1266 mutex_lock(&udc_lock);
1267 list_for_each_entry(udc, &udc_list, list) {
1268 if (!udc->driver) {
1269 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1270 break;
1271 }
1272 }
1273 mutex_unlock(&udc_lock);
1274 return name;
1275 }
1276 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1277
1278 /**
1279 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1280 * @parent: the parent device to this udc. Usually the controller
1281 * driver's device.
1282 * @gadget: the gadget to be added to the list
1283 *
1284 * Returns zero on success, negative errno otherwise.
1285 */
1286 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1287 {
1288 return usb_add_gadget_udc_release(parent, gadget, NULL);
1289 }
1290 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1291
1292 static void usb_gadget_remove_driver(struct usb_udc *udc)
1293 {
1294 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
1295 udc->driver->function);
1296
1297 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1298
1299 usb_gadget_disconnect(udc->gadget);
1300 udc->driver->unbind(udc->gadget);
1301 usb_gadget_udc_stop(udc);
1302
1303 udc->driver = NULL;
1304 udc->dev.driver = NULL;
1305 udc->gadget->dev.driver = NULL;
1306 }
1307
1308 /**
1309 * usb_del_gadget_udc - deletes @udc from udc_list
1310 * @gadget: the gadget to be removed.
1311 *
1312 * This, will call usb_gadget_unregister_driver() if
1313 * the @udc is still busy.
1314 */
1315 void usb_del_gadget_udc(struct usb_gadget *gadget)
1316 {
1317 struct usb_udc *udc = gadget->udc;
1318
1319 if (!udc)
1320 return;
1321
1322 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1323
1324 mutex_lock(&udc_lock);
1325 list_del(&udc->list);
1326
1327 if (udc->driver) {
1328 struct usb_gadget_driver *driver = udc->driver;
1329
1330 usb_gadget_remove_driver(udc);
1331 list_add(&driver->pending, &gadget_driver_pending_list);
1332 }
1333 mutex_unlock(&udc_lock);
1334
1335 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1336 flush_work(&gadget->work);
1337 device_unregister(&udc->dev);
1338 device_unregister(&gadget->dev);
1339 memset(&gadget->dev, 0x00, sizeof(gadget->dev));
1340 }
1341 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1342
1343 /* ------------------------------------------------------------------------- */
1344
1345 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
1346 {
1347 int ret;
1348
1349 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
1350 driver->function);
1351
1352 udc->driver = driver;
1353 udc->dev.driver = &driver->driver;
1354 udc->gadget->dev.driver = &driver->driver;
1355
1356 usb_gadget_udc_set_speed(udc, driver->max_speed);
1357
1358 ret = driver->bind(udc->gadget, driver);
1359 if (ret)
1360 goto err1;
1361 ret = usb_gadget_udc_start(udc);
1362 if (ret) {
1363 driver->unbind(udc->gadget);
1364 goto err1;
1365 }
1366 usb_udc_connect_control(udc);
1367
1368 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1369 return 0;
1370 err1:
1371 if (ret != -EISNAM)
1372 dev_err(&udc->dev, "failed to start %s: %d\n",
1373 udc->driver->function, ret);
1374 udc->driver = NULL;
1375 udc->dev.driver = NULL;
1376 udc->gadget->dev.driver = NULL;
1377 return ret;
1378 }
1379
1380 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
1381 {
1382 struct usb_udc *udc = NULL;
1383 int ret = -ENODEV;
1384
1385 if (!driver || !driver->bind || !driver->setup)
1386 return -EINVAL;
1387
1388 mutex_lock(&udc_lock);
1389 if (driver->udc_name) {
1390 list_for_each_entry(udc, &udc_list, list) {
1391 ret = strcmp(driver->udc_name, dev_name(&udc->dev));
1392 if (!ret)
1393 break;
1394 }
1395 if (ret)
1396 ret = -ENODEV;
1397 else if (udc->driver)
1398 ret = -EBUSY;
1399 else
1400 goto found;
1401 } else {
1402 list_for_each_entry(udc, &udc_list, list) {
1403 /* For now we take the first one */
1404 if (!udc->driver)
1405 goto found;
1406 }
1407 }
1408
1409 if (!driver->match_existing_only) {
1410 list_add_tail(&driver->pending, &gadget_driver_pending_list);
1411 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
1412 driver->function);
1413 ret = 0;
1414 }
1415
1416 mutex_unlock(&udc_lock);
1417 return ret;
1418 found:
1419 ret = udc_bind_to_driver(udc, driver);
1420 mutex_unlock(&udc_lock);
1421 return ret;
1422 }
1423 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
1424
1425 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1426 {
1427 struct usb_udc *udc = NULL;
1428 int ret = -ENODEV;
1429
1430 if (!driver || !driver->unbind)
1431 return -EINVAL;
1432
1433 mutex_lock(&udc_lock);
1434 list_for_each_entry(udc, &udc_list, list) {
1435 if (udc->driver == driver) {
1436 usb_gadget_remove_driver(udc);
1437 usb_gadget_set_state(udc->gadget,
1438 USB_STATE_NOTATTACHED);
1439
1440 /* Maybe there is someone waiting for this UDC? */
1441 check_pending_gadget_drivers(udc);
1442 /*
1443 * For now we ignore bind errors as probably it's
1444 * not a valid reason to fail other's gadget unbind
1445 */
1446 ret = 0;
1447 break;
1448 }
1449 }
1450
1451 if (ret) {
1452 list_del(&driver->pending);
1453 ret = 0;
1454 }
1455 mutex_unlock(&udc_lock);
1456 return ret;
1457 }
1458 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1459
1460 /* ------------------------------------------------------------------------- */
1461
1462 static ssize_t srp_store(struct device *dev,
1463 struct device_attribute *attr, const char *buf, size_t n)
1464 {
1465 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1466
1467 if (sysfs_streq(buf, "1"))
1468 usb_gadget_wakeup(udc->gadget);
1469
1470 return n;
1471 }
1472 static DEVICE_ATTR_WO(srp);
1473
1474 static ssize_t soft_connect_store(struct device *dev,
1475 struct device_attribute *attr, const char *buf, size_t n)
1476 {
1477 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1478
1479 if (!udc->driver) {
1480 dev_err(dev, "soft-connect without a gadget driver\n");
1481 return -EOPNOTSUPP;
1482 }
1483
1484 if (sysfs_streq(buf, "connect")) {
1485 usb_gadget_udc_start(udc);
1486 usb_gadget_connect(udc->gadget);
1487 } else if (sysfs_streq(buf, "disconnect")) {
1488 usb_gadget_disconnect(udc->gadget);
1489 usb_gadget_udc_stop(udc);
1490 } else {
1491 dev_err(dev, "unsupported command '%s'\n", buf);
1492 return -EINVAL;
1493 }
1494
1495 return n;
1496 }
1497 static DEVICE_ATTR_WO(soft_connect);
1498
1499 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1500 char *buf)
1501 {
1502 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1503 struct usb_gadget *gadget = udc->gadget;
1504
1505 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1506 }
1507 static DEVICE_ATTR_RO(state);
1508
1509 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1510 char *buf)
1511 {
1512 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1513 struct usb_gadget_driver *drv = udc->driver;
1514
1515 if (!drv || !drv->function)
1516 return 0;
1517 return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1518 }
1519 static DEVICE_ATTR_RO(function);
1520
1521 #define USB_UDC_SPEED_ATTR(name, param) \
1522 ssize_t name##_show(struct device *dev, \
1523 struct device_attribute *attr, char *buf) \
1524 { \
1525 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1526 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1527 usb_speed_string(udc->gadget->param)); \
1528 } \
1529 static DEVICE_ATTR_RO(name)
1530
1531 static USB_UDC_SPEED_ATTR(current_speed, speed);
1532 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1533
1534 #define USB_UDC_ATTR(name) \
1535 ssize_t name##_show(struct device *dev, \
1536 struct device_attribute *attr, char *buf) \
1537 { \
1538 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1539 struct usb_gadget *gadget = udc->gadget; \
1540 \
1541 return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1542 } \
1543 static DEVICE_ATTR_RO(name)
1544
1545 static USB_UDC_ATTR(is_otg);
1546 static USB_UDC_ATTR(is_a_peripheral);
1547 static USB_UDC_ATTR(b_hnp_enable);
1548 static USB_UDC_ATTR(a_hnp_support);
1549 static USB_UDC_ATTR(a_alt_hnp_support);
1550 static USB_UDC_ATTR(is_selfpowered);
1551
1552 static struct attribute *usb_udc_attrs[] = {
1553 &dev_attr_srp.attr,
1554 &dev_attr_soft_connect.attr,
1555 &dev_attr_state.attr,
1556 &dev_attr_function.attr,
1557 &dev_attr_current_speed.attr,
1558 &dev_attr_maximum_speed.attr,
1559
1560 &dev_attr_is_otg.attr,
1561 &dev_attr_is_a_peripheral.attr,
1562 &dev_attr_b_hnp_enable.attr,
1563 &dev_attr_a_hnp_support.attr,
1564 &dev_attr_a_alt_hnp_support.attr,
1565 &dev_attr_is_selfpowered.attr,
1566 NULL,
1567 };
1568
1569 static const struct attribute_group usb_udc_attr_group = {
1570 .attrs = usb_udc_attrs,
1571 };
1572
1573 static const struct attribute_group *usb_udc_attr_groups[] = {
1574 &usb_udc_attr_group,
1575 NULL,
1576 };
1577
1578 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
1579 {
1580 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1581 int ret;
1582
1583 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1584 if (ret) {
1585 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1586 return ret;
1587 }
1588
1589 if (udc->driver) {
1590 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1591 udc->driver->function);
1592 if (ret) {
1593 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1594 return ret;
1595 }
1596 }
1597
1598 return 0;
1599 }
1600
1601 static int __init usb_udc_init(void)
1602 {
1603 udc_class = class_create(THIS_MODULE, "udc");
1604 if (IS_ERR(udc_class)) {
1605 pr_err("failed to create udc class --> %ld\n",
1606 PTR_ERR(udc_class));
1607 return PTR_ERR(udc_class);
1608 }
1609
1610 udc_class->dev_uevent = usb_udc_uevent;
1611 return 0;
1612 }
1613 subsys_initcall(usb_udc_init);
1614
1615 static void __exit usb_udc_exit(void)
1616 {
1617 class_destroy(udc_class);
1618 }
1619 module_exit(usb_udc_exit);
1620
1621 MODULE_DESCRIPTION("UDC Framework");
1622 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1623 MODULE_LICENSE("GPL v2");