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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#define pr_fmt(fmt) "UDC core: " fmt
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/device.h>
14#include <linux/list.h>
15#include <linux/idr.h>
16#include <linux/err.h>
17#include <linux/dma-mapping.h>
18#include <linux/sched/task_stack.h>
19#include <linux/workqueue.h>
20
21#include <linux/usb/ch9.h>
22#include <linux/usb/gadget.h>
23#include <linux/usb.h>
24
25#include "trace.h"
26
27static DEFINE_IDA(gadget_id_numbers);
28
29static const struct bus_type gadget_bus_type;
30
31/**
32 * struct usb_udc - describes one usb device controller
33 * @driver: the gadget driver pointer. For use by the class code
34 * @dev: the child device to the actual controller
35 * @gadget: the gadget. For use by the class code
36 * @list: for use by the udc class driver
37 * @vbus: for udcs who care about vbus status, this value is real vbus status;
38 * for udcs who do not care about vbus status, this value is always true
39 * @started: the UDC's started state. True if the UDC had started.
40 * @allow_connect: Indicates whether UDC is allowed to be pulled up.
41 * Set/cleared by gadget_(un)bind_driver() after gadget driver is bound or
42 * unbound.
43 * @vbus_work: work routine to handle VBUS status change notifications.
44 * @connect_lock: protects udc->started, gadget->connect,
45 * gadget->allow_connect and gadget->deactivate. The routines
46 * usb_gadget_connect_locked(), usb_gadget_disconnect_locked(),
47 * usb_udc_connect_control_locked(), usb_gadget_udc_start_locked() and
48 * usb_gadget_udc_stop_locked() are called with this lock held.
49 *
50 * This represents the internal data structure which is used by the UDC-class
51 * to hold information about udc driver and gadget together.
52 */
53struct usb_udc {
54 struct usb_gadget_driver *driver;
55 struct usb_gadget *gadget;
56 struct device dev;
57 struct list_head list;
58 bool vbus;
59 bool started;
60 bool allow_connect;
61 struct work_struct vbus_work;
62 struct mutex connect_lock;
63};
64
65static const struct class udc_class;
66static LIST_HEAD(udc_list);
67
68/* Protects udc_list, udc->driver, driver->is_bound, and related calls */
69static DEFINE_MUTEX(udc_lock);
70
71/* ------------------------------------------------------------------------- */
72
73/**
74 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
75 * @ep:the endpoint being configured
76 * @maxpacket_limit:value of maximum packet size limit
77 *
78 * This function should be used only in UDC drivers to initialize endpoint
79 * (usually in probe function).
80 */
81void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
82 unsigned maxpacket_limit)
83{
84 ep->maxpacket_limit = maxpacket_limit;
85 ep->maxpacket = maxpacket_limit;
86
87 trace_usb_ep_set_maxpacket_limit(ep, 0);
88}
89EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
90
91/**
92 * usb_ep_enable - configure endpoint, making it usable
93 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
94 * drivers discover endpoints through the ep_list of a usb_gadget.
95 *
96 * When configurations are set, or when interface settings change, the driver
97 * will enable or disable the relevant endpoints. while it is enabled, an
98 * endpoint may be used for i/o until the driver receives a disconnect() from
99 * the host or until the endpoint is disabled.
100 *
101 * the ep0 implementation (which calls this routine) must ensure that the
102 * hardware capabilities of each endpoint match the descriptor provided
103 * for it. for example, an endpoint named "ep2in-bulk" would be usable
104 * for interrupt transfers as well as bulk, but it likely couldn't be used
105 * for iso transfers or for endpoint 14. some endpoints are fully
106 * configurable, with more generic names like "ep-a". (remember that for
107 * USB, "in" means "towards the USB host".)
108 *
109 * This routine may be called in an atomic (interrupt) context.
110 *
111 * returns zero, or a negative error code.
112 */
113int usb_ep_enable(struct usb_ep *ep)
114{
115 int ret = 0;
116
117 if (ep->enabled)
118 goto out;
119
120 /* UDC drivers can't handle endpoints with maxpacket size 0 */
121 if (usb_endpoint_maxp(ep->desc) == 0) {
122 /*
123 * We should log an error message here, but we can't call
124 * dev_err() because there's no way to find the gadget
125 * given only ep.
126 */
127 ret = -EINVAL;
128 goto out;
129 }
130
131 ret = ep->ops->enable(ep, ep->desc);
132 if (ret)
133 goto out;
134
135 ep->enabled = true;
136
137out:
138 trace_usb_ep_enable(ep, ret);
139
140 return ret;
141}
142EXPORT_SYMBOL_GPL(usb_ep_enable);
143
144/**
145 * usb_ep_disable - endpoint is no longer usable
146 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
147 *
148 * no other task may be using this endpoint when this is called.
149 * any pending and uncompleted requests will complete with status
150 * indicating disconnect (-ESHUTDOWN) before this call returns.
151 * gadget drivers must call usb_ep_enable() again before queueing
152 * requests to the endpoint.
153 *
154 * This routine may be called in an atomic (interrupt) context.
155 *
156 * returns zero, or a negative error code.
157 */
158int usb_ep_disable(struct usb_ep *ep)
159{
160 int ret = 0;
161
162 if (!ep->enabled)
163 goto out;
164
165 ret = ep->ops->disable(ep);
166 if (ret)
167 goto out;
168
169 ep->enabled = false;
170
171out:
172 trace_usb_ep_disable(ep, ret);
173
174 return ret;
175}
176EXPORT_SYMBOL_GPL(usb_ep_disable);
177
178/**
179 * usb_ep_alloc_request - allocate a request object to use with this endpoint
180 * @ep:the endpoint to be used with with the request
181 * @gfp_flags:GFP_* flags to use
182 *
183 * Request objects must be allocated with this call, since they normally
184 * need controller-specific setup and may even need endpoint-specific
185 * resources such as allocation of DMA descriptors.
186 * Requests may be submitted with usb_ep_queue(), and receive a single
187 * completion callback. Free requests with usb_ep_free_request(), when
188 * they are no longer needed.
189 *
190 * Returns the request, or null if one could not be allocated.
191 */
192struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
193 gfp_t gfp_flags)
194{
195 struct usb_request *req = NULL;
196
197 req = ep->ops->alloc_request(ep, gfp_flags);
198
199 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
200
201 return req;
202}
203EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
204
205/**
206 * usb_ep_free_request - frees a request object
207 * @ep:the endpoint associated with the request
208 * @req:the request being freed
209 *
210 * Reverses the effect of usb_ep_alloc_request().
211 * Caller guarantees the request is not queued, and that it will
212 * no longer be requeued (or otherwise used).
213 */
214void usb_ep_free_request(struct usb_ep *ep,
215 struct usb_request *req)
216{
217 trace_usb_ep_free_request(ep, req, 0);
218 ep->ops->free_request(ep, req);
219}
220EXPORT_SYMBOL_GPL(usb_ep_free_request);
221
222/**
223 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
224 * @ep:the endpoint associated with the request
225 * @req:the request being submitted
226 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
227 * pre-allocate all necessary memory with the request.
228 *
229 * This tells the device controller to perform the specified request through
230 * that endpoint (reading or writing a buffer). When the request completes,
231 * including being canceled by usb_ep_dequeue(), the request's completion
232 * routine is called to return the request to the driver. Any endpoint
233 * (except control endpoints like ep0) may have more than one transfer
234 * request queued; they complete in FIFO order. Once a gadget driver
235 * submits a request, that request may not be examined or modified until it
236 * is given back to that driver through the completion callback.
237 *
238 * Each request is turned into one or more packets. The controller driver
239 * never merges adjacent requests into the same packet. OUT transfers
240 * will sometimes use data that's already buffered in the hardware.
241 * Drivers can rely on the fact that the first byte of the request's buffer
242 * always corresponds to the first byte of some USB packet, for both
243 * IN and OUT transfers.
244 *
245 * Bulk endpoints can queue any amount of data; the transfer is packetized
246 * automatically. The last packet will be short if the request doesn't fill it
247 * out completely. Zero length packets (ZLPs) should be avoided in portable
248 * protocols since not all usb hardware can successfully handle zero length
249 * packets. (ZLPs may be explicitly written, and may be implicitly written if
250 * the request 'zero' flag is set.) Bulk endpoints may also be used
251 * for interrupt transfers; but the reverse is not true, and some endpoints
252 * won't support every interrupt transfer. (Such as 768 byte packets.)
253 *
254 * Interrupt-only endpoints are less functional than bulk endpoints, for
255 * example by not supporting queueing or not handling buffers that are
256 * larger than the endpoint's maxpacket size. They may also treat data
257 * toggle differently.
258 *
259 * Control endpoints ... after getting a setup() callback, the driver queues
260 * one response (even if it would be zero length). That enables the
261 * status ack, after transferring data as specified in the response. Setup
262 * functions may return negative error codes to generate protocol stalls.
263 * (Note that some USB device controllers disallow protocol stall responses
264 * in some cases.) When control responses are deferred (the response is
265 * written after the setup callback returns), then usb_ep_set_halt() may be
266 * used on ep0 to trigger protocol stalls. Depending on the controller,
267 * it may not be possible to trigger a status-stage protocol stall when the
268 * data stage is over, that is, from within the response's completion
269 * routine.
270 *
271 * For periodic endpoints, like interrupt or isochronous ones, the usb host
272 * arranges to poll once per interval, and the gadget driver usually will
273 * have queued some data to transfer at that time.
274 *
275 * Note that @req's ->complete() callback must never be called from
276 * within usb_ep_queue() as that can create deadlock situations.
277 *
278 * This routine may be called in interrupt context.
279 *
280 * Returns zero, or a negative error code. Endpoints that are not enabled
281 * report errors; errors will also be
282 * reported when the usb peripheral is disconnected.
283 *
284 * If and only if @req is successfully queued (the return value is zero),
285 * @req->complete() will be called exactly once, when the Gadget core and
286 * UDC are finished with the request. When the completion function is called,
287 * control of the request is returned to the device driver which submitted it.
288 * The completion handler may then immediately free or reuse @req.
289 */
290int usb_ep_queue(struct usb_ep *ep,
291 struct usb_request *req, gfp_t gfp_flags)
292{
293 int ret = 0;
294
295 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
296 ret = -ESHUTDOWN;
297 goto out;
298 }
299
300 ret = ep->ops->queue(ep, req, gfp_flags);
301
302out:
303 trace_usb_ep_queue(ep, req, ret);
304
305 return ret;
306}
307EXPORT_SYMBOL_GPL(usb_ep_queue);
308
309/**
310 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
311 * @ep:the endpoint associated with the request
312 * @req:the request being canceled
313 *
314 * If the request is still active on the endpoint, it is dequeued and
315 * eventually its completion routine is called (with status -ECONNRESET);
316 * else a negative error code is returned. This routine is asynchronous,
317 * that is, it may return before the completion routine runs.
318 *
319 * Note that some hardware can't clear out write fifos (to unlink the request
320 * at the head of the queue) except as part of disconnecting from usb. Such
321 * restrictions prevent drivers from supporting configuration changes,
322 * even to configuration zero (a "chapter 9" requirement).
323 *
324 * This routine may be called in interrupt context.
325 */
326int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
327{
328 int ret;
329
330 ret = ep->ops->dequeue(ep, req);
331 trace_usb_ep_dequeue(ep, req, ret);
332
333 return ret;
334}
335EXPORT_SYMBOL_GPL(usb_ep_dequeue);
336
337/**
338 * usb_ep_set_halt - sets the endpoint halt feature.
339 * @ep: the non-isochronous endpoint being stalled
340 *
341 * Use this to stall an endpoint, perhaps as an error report.
342 * Except for control endpoints,
343 * the endpoint stays halted (will not stream any data) until the host
344 * clears this feature; drivers may need to empty the endpoint's request
345 * queue first, to make sure no inappropriate transfers happen.
346 *
347 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
348 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
349 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
350 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
351 *
352 * This routine may be called in interrupt context.
353 *
354 * Returns zero, or a negative error code. On success, this call sets
355 * underlying hardware state that blocks data transfers.
356 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
357 * transfer requests are still queued, or if the controller hardware
358 * (usually a FIFO) still holds bytes that the host hasn't collected.
359 */
360int usb_ep_set_halt(struct usb_ep *ep)
361{
362 int ret;
363
364 ret = ep->ops->set_halt(ep, 1);
365 trace_usb_ep_set_halt(ep, ret);
366
367 return ret;
368}
369EXPORT_SYMBOL_GPL(usb_ep_set_halt);
370
371/**
372 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
373 * @ep:the bulk or interrupt endpoint being reset
374 *
375 * Use this when responding to the standard usb "set interface" request,
376 * for endpoints that aren't reconfigured, after clearing any other state
377 * in the endpoint's i/o queue.
378 *
379 * This routine may be called in interrupt context.
380 *
381 * Returns zero, or a negative error code. On success, this call clears
382 * the underlying hardware state reflecting endpoint halt and data toggle.
383 * Note that some hardware can't support this request (like pxa2xx_udc),
384 * and accordingly can't correctly implement interface altsettings.
385 */
386int usb_ep_clear_halt(struct usb_ep *ep)
387{
388 int ret;
389
390 ret = ep->ops->set_halt(ep, 0);
391 trace_usb_ep_clear_halt(ep, ret);
392
393 return ret;
394}
395EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
396
397/**
398 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
399 * @ep: the endpoint being wedged
400 *
401 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
402 * requests. If the gadget driver clears the halt status, it will
403 * automatically unwedge the endpoint.
404 *
405 * This routine may be called in interrupt context.
406 *
407 * Returns zero on success, else negative errno.
408 */
409int usb_ep_set_wedge(struct usb_ep *ep)
410{
411 int ret;
412
413 if (ep->ops->set_wedge)
414 ret = ep->ops->set_wedge(ep);
415 else
416 ret = ep->ops->set_halt(ep, 1);
417
418 trace_usb_ep_set_wedge(ep, ret);
419
420 return ret;
421}
422EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
423
424/**
425 * usb_ep_fifo_status - returns number of bytes in fifo, or error
426 * @ep: the endpoint whose fifo status is being checked.
427 *
428 * FIFO endpoints may have "unclaimed data" in them in certain cases,
429 * such as after aborted transfers. Hosts may not have collected all
430 * the IN data written by the gadget driver (and reported by a request
431 * completion). The gadget driver may not have collected all the data
432 * written OUT to it by the host. Drivers that need precise handling for
433 * fault reporting or recovery may need to use this call.
434 *
435 * This routine may be called in interrupt context.
436 *
437 * This returns the number of such bytes in the fifo, or a negative
438 * errno if the endpoint doesn't use a FIFO or doesn't support such
439 * precise handling.
440 */
441int usb_ep_fifo_status(struct usb_ep *ep)
442{
443 int ret;
444
445 if (ep->ops->fifo_status)
446 ret = ep->ops->fifo_status(ep);
447 else
448 ret = -EOPNOTSUPP;
449
450 trace_usb_ep_fifo_status(ep, ret);
451
452 return ret;
453}
454EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
455
456/**
457 * usb_ep_fifo_flush - flushes contents of a fifo
458 * @ep: the endpoint whose fifo is being flushed.
459 *
460 * This call may be used to flush the "unclaimed data" that may exist in
461 * an endpoint fifo after abnormal transaction terminations. The call
462 * must never be used except when endpoint is not being used for any
463 * protocol translation.
464 *
465 * This routine may be called in interrupt context.
466 */
467void usb_ep_fifo_flush(struct usb_ep *ep)
468{
469 if (ep->ops->fifo_flush)
470 ep->ops->fifo_flush(ep);
471
472 trace_usb_ep_fifo_flush(ep, 0);
473}
474EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
475
476/* ------------------------------------------------------------------------- */
477
478/**
479 * usb_gadget_frame_number - returns the current frame number
480 * @gadget: controller that reports the frame number
481 *
482 * Returns the usb frame number, normally eleven bits from a SOF packet,
483 * or negative errno if this device doesn't support this capability.
484 */
485int usb_gadget_frame_number(struct usb_gadget *gadget)
486{
487 int ret;
488
489 ret = gadget->ops->get_frame(gadget);
490
491 trace_usb_gadget_frame_number(gadget, ret);
492
493 return ret;
494}
495EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
496
497/**
498 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
499 * @gadget: controller used to wake up the host
500 *
501 * Returns zero on success, else negative error code if the hardware
502 * doesn't support such attempts, or its support has not been enabled
503 * by the usb host. Drivers must return device descriptors that report
504 * their ability to support this, or hosts won't enable it.
505 *
506 * This may also try to use SRP to wake the host and start enumeration,
507 * even if OTG isn't otherwise in use. OTG devices may also start
508 * remote wakeup even when hosts don't explicitly enable it.
509 */
510int usb_gadget_wakeup(struct usb_gadget *gadget)
511{
512 int ret = 0;
513
514 if (!gadget->ops->wakeup) {
515 ret = -EOPNOTSUPP;
516 goto out;
517 }
518
519 ret = gadget->ops->wakeup(gadget);
520
521out:
522 trace_usb_gadget_wakeup(gadget, ret);
523
524 return ret;
525}
526EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
527
528/**
529 * usb_gadget_set_remote_wakeup - configures the device remote wakeup feature.
530 * @gadget:the device being configured for remote wakeup
531 * @set:value to be configured.
532 *
533 * set to one to enable remote wakeup feature and zero to disable it.
534 *
535 * returns zero on success, else negative errno.
536 */
537int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set)
538{
539 int ret = 0;
540
541 if (!gadget->ops->set_remote_wakeup) {
542 ret = -EOPNOTSUPP;
543 goto out;
544 }
545
546 ret = gadget->ops->set_remote_wakeup(gadget, set);
547
548out:
549 trace_usb_gadget_set_remote_wakeup(gadget, ret);
550
551 return ret;
552}
553EXPORT_SYMBOL_GPL(usb_gadget_set_remote_wakeup);
554
555/**
556 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
557 * @gadget:the device being declared as self-powered
558 *
559 * this affects the device status reported by the hardware driver
560 * to reflect that it now has a local power supply.
561 *
562 * returns zero on success, else negative errno.
563 */
564int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
565{
566 int ret = 0;
567
568 if (!gadget->ops->set_selfpowered) {
569 ret = -EOPNOTSUPP;
570 goto out;
571 }
572
573 ret = gadget->ops->set_selfpowered(gadget, 1);
574
575out:
576 trace_usb_gadget_set_selfpowered(gadget, ret);
577
578 return ret;
579}
580EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
581
582/**
583 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
584 * @gadget:the device being declared as bus-powered
585 *
586 * this affects the device status reported by the hardware driver.
587 * some hardware may not support bus-powered operation, in which
588 * case this feature's value can never change.
589 *
590 * returns zero on success, else negative errno.
591 */
592int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
593{
594 int ret = 0;
595
596 if (!gadget->ops->set_selfpowered) {
597 ret = -EOPNOTSUPP;
598 goto out;
599 }
600
601 ret = gadget->ops->set_selfpowered(gadget, 0);
602
603out:
604 trace_usb_gadget_clear_selfpowered(gadget, ret);
605
606 return ret;
607}
608EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
609
610/**
611 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
612 * @gadget:The device which now has VBUS power.
613 * Context: can sleep
614 *
615 * This call is used by a driver for an external transceiver (or GPIO)
616 * that detects a VBUS power session starting. Common responses include
617 * resuming the controller, activating the D+ (or D-) pullup to let the
618 * host detect that a USB device is attached, and starting to draw power
619 * (8mA or possibly more, especially after SET_CONFIGURATION).
620 *
621 * Returns zero on success, else negative errno.
622 */
623int usb_gadget_vbus_connect(struct usb_gadget *gadget)
624{
625 int ret = 0;
626
627 if (!gadget->ops->vbus_session) {
628 ret = -EOPNOTSUPP;
629 goto out;
630 }
631
632 ret = gadget->ops->vbus_session(gadget, 1);
633
634out:
635 trace_usb_gadget_vbus_connect(gadget, ret);
636
637 return ret;
638}
639EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
640
641/**
642 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
643 * @gadget:The device whose VBUS usage is being described
644 * @mA:How much current to draw, in milliAmperes. This should be twice
645 * the value listed in the configuration descriptor bMaxPower field.
646 *
647 * This call is used by gadget drivers during SET_CONFIGURATION calls,
648 * reporting how much power the device may consume. For example, this
649 * could affect how quickly batteries are recharged.
650 *
651 * Returns zero on success, else negative errno.
652 */
653int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
654{
655 int ret = 0;
656
657 if (!gadget->ops->vbus_draw) {
658 ret = -EOPNOTSUPP;
659 goto out;
660 }
661
662 ret = gadget->ops->vbus_draw(gadget, mA);
663 if (!ret)
664 gadget->mA = mA;
665
666out:
667 trace_usb_gadget_vbus_draw(gadget, ret);
668
669 return ret;
670}
671EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
672
673/**
674 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
675 * @gadget:the device whose VBUS supply is being described
676 * Context: can sleep
677 *
678 * This call is used by a driver for an external transceiver (or GPIO)
679 * that detects a VBUS power session ending. Common responses include
680 * reversing everything done in usb_gadget_vbus_connect().
681 *
682 * Returns zero on success, else negative errno.
683 */
684int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
685{
686 int ret = 0;
687
688 if (!gadget->ops->vbus_session) {
689 ret = -EOPNOTSUPP;
690 goto out;
691 }
692
693 ret = gadget->ops->vbus_session(gadget, 0);
694
695out:
696 trace_usb_gadget_vbus_disconnect(gadget, ret);
697
698 return ret;
699}
700EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
701
702static int usb_gadget_connect_locked(struct usb_gadget *gadget)
703 __must_hold(&gadget->udc->connect_lock)
704{
705 int ret = 0;
706
707 if (!gadget->ops->pullup) {
708 ret = -EOPNOTSUPP;
709 goto out;
710 }
711
712 if (gadget->deactivated || !gadget->udc->allow_connect || !gadget->udc->started) {
713 /*
714 * If the gadget isn't usable (because it is deactivated,
715 * unbound, or not yet started), we only save the new state.
716 * The gadget will be connected automatically when it is
717 * activated/bound/started.
718 */
719 gadget->connected = true;
720 goto out;
721 }
722
723 ret = gadget->ops->pullup(gadget, 1);
724 if (!ret)
725 gadget->connected = 1;
726
727out:
728 trace_usb_gadget_connect(gadget, ret);
729
730 return ret;
731}
732
733/**
734 * usb_gadget_connect - software-controlled connect to USB host
735 * @gadget:the peripheral being connected
736 *
737 * Enables the D+ (or potentially D-) pullup. The host will start
738 * enumerating this gadget when the pullup is active and a VBUS session
739 * is active (the link is powered).
740 *
741 * Returns zero on success, else negative errno.
742 */
743int usb_gadget_connect(struct usb_gadget *gadget)
744{
745 int ret;
746
747 mutex_lock(&gadget->udc->connect_lock);
748 ret = usb_gadget_connect_locked(gadget);
749 mutex_unlock(&gadget->udc->connect_lock);
750
751 return ret;
752}
753EXPORT_SYMBOL_GPL(usb_gadget_connect);
754
755static int usb_gadget_disconnect_locked(struct usb_gadget *gadget)
756 __must_hold(&gadget->udc->connect_lock)
757{
758 int ret = 0;
759
760 if (!gadget->ops->pullup) {
761 ret = -EOPNOTSUPP;
762 goto out;
763 }
764
765 if (!gadget->connected)
766 goto out;
767
768 if (gadget->deactivated || !gadget->udc->started) {
769 /*
770 * If gadget is deactivated we only save new state.
771 * Gadget will stay disconnected after activation.
772 */
773 gadget->connected = false;
774 goto out;
775 }
776
777 ret = gadget->ops->pullup(gadget, 0);
778 if (!ret)
779 gadget->connected = 0;
780
781 mutex_lock(&udc_lock);
782 if (gadget->udc->driver)
783 gadget->udc->driver->disconnect(gadget);
784 mutex_unlock(&udc_lock);
785
786out:
787 trace_usb_gadget_disconnect(gadget, ret);
788
789 return ret;
790}
791
792/**
793 * usb_gadget_disconnect - software-controlled disconnect from USB host
794 * @gadget:the peripheral being disconnected
795 *
796 * Disables the D+ (or potentially D-) pullup, which the host may see
797 * as a disconnect (when a VBUS session is active). Not all systems
798 * support software pullup controls.
799 *
800 * Following a successful disconnect, invoke the ->disconnect() callback
801 * for the current gadget driver so that UDC drivers don't need to.
802 *
803 * Returns zero on success, else negative errno.
804 */
805int usb_gadget_disconnect(struct usb_gadget *gadget)
806{
807 int ret;
808
809 mutex_lock(&gadget->udc->connect_lock);
810 ret = usb_gadget_disconnect_locked(gadget);
811 mutex_unlock(&gadget->udc->connect_lock);
812
813 return ret;
814}
815EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
816
817/**
818 * usb_gadget_deactivate - deactivate function which is not ready to work
819 * @gadget: the peripheral being deactivated
820 *
821 * This routine may be used during the gadget driver bind() call to prevent
822 * the peripheral from ever being visible to the USB host, unless later
823 * usb_gadget_activate() is called. For example, user mode components may
824 * need to be activated before the system can talk to hosts.
825 *
826 * This routine may sleep; it must not be called in interrupt context
827 * (such as from within a gadget driver's disconnect() callback).
828 *
829 * Returns zero on success, else negative errno.
830 */
831int usb_gadget_deactivate(struct usb_gadget *gadget)
832{
833 int ret = 0;
834
835 mutex_lock(&gadget->udc->connect_lock);
836 if (gadget->deactivated)
837 goto unlock;
838
839 if (gadget->connected) {
840 ret = usb_gadget_disconnect_locked(gadget);
841 if (ret)
842 goto unlock;
843
844 /*
845 * If gadget was being connected before deactivation, we want
846 * to reconnect it in usb_gadget_activate().
847 */
848 gadget->connected = true;
849 }
850 gadget->deactivated = true;
851
852unlock:
853 mutex_unlock(&gadget->udc->connect_lock);
854 trace_usb_gadget_deactivate(gadget, ret);
855
856 return ret;
857}
858EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
859
860/**
861 * usb_gadget_activate - activate function which is not ready to work
862 * @gadget: the peripheral being activated
863 *
864 * This routine activates gadget which was previously deactivated with
865 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
866 *
867 * This routine may sleep; it must not be called in interrupt context.
868 *
869 * Returns zero on success, else negative errno.
870 */
871int usb_gadget_activate(struct usb_gadget *gadget)
872{
873 int ret = 0;
874
875 mutex_lock(&gadget->udc->connect_lock);
876 if (!gadget->deactivated)
877 goto unlock;
878
879 gadget->deactivated = false;
880
881 /*
882 * If gadget has been connected before deactivation, or became connected
883 * while it was being deactivated, we call usb_gadget_connect().
884 */
885 if (gadget->connected)
886 ret = usb_gadget_connect_locked(gadget);
887
888unlock:
889 mutex_unlock(&gadget->udc->connect_lock);
890 trace_usb_gadget_activate(gadget, ret);
891
892 return ret;
893}
894EXPORT_SYMBOL_GPL(usb_gadget_activate);
895
896/* ------------------------------------------------------------------------- */
897
898#ifdef CONFIG_HAS_DMA
899
900int usb_gadget_map_request_by_dev(struct device *dev,
901 struct usb_request *req, int is_in)
902{
903 if (req->length == 0)
904 return 0;
905
906 if (req->num_sgs) {
907 int mapped;
908
909 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
910 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
911 if (mapped == 0) {
912 dev_err(dev, "failed to map SGs\n");
913 return -EFAULT;
914 }
915
916 req->num_mapped_sgs = mapped;
917 } else {
918 if (is_vmalloc_addr(req->buf)) {
919 dev_err(dev, "buffer is not dma capable\n");
920 return -EFAULT;
921 } else if (object_is_on_stack(req->buf)) {
922 dev_err(dev, "buffer is on stack\n");
923 return -EFAULT;
924 }
925
926 req->dma = dma_map_single(dev, req->buf, req->length,
927 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
928
929 if (dma_mapping_error(dev, req->dma)) {
930 dev_err(dev, "failed to map buffer\n");
931 return -EFAULT;
932 }
933
934 req->dma_mapped = 1;
935 }
936
937 return 0;
938}
939EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
940
941int usb_gadget_map_request(struct usb_gadget *gadget,
942 struct usb_request *req, int is_in)
943{
944 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
945}
946EXPORT_SYMBOL_GPL(usb_gadget_map_request);
947
948void usb_gadget_unmap_request_by_dev(struct device *dev,
949 struct usb_request *req, int is_in)
950{
951 if (req->length == 0)
952 return;
953
954 if (req->num_mapped_sgs) {
955 dma_unmap_sg(dev, req->sg, req->num_sgs,
956 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
957
958 req->num_mapped_sgs = 0;
959 } else if (req->dma_mapped) {
960 dma_unmap_single(dev, req->dma, req->length,
961 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
962 req->dma_mapped = 0;
963 }
964}
965EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
966
967void usb_gadget_unmap_request(struct usb_gadget *gadget,
968 struct usb_request *req, int is_in)
969{
970 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
971}
972EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
973
974#endif /* CONFIG_HAS_DMA */
975
976/* ------------------------------------------------------------------------- */
977
978/**
979 * usb_gadget_giveback_request - give the request back to the gadget layer
980 * @ep: the endpoint to be used with with the request
981 * @req: the request being given back
982 *
983 * This is called by device controller drivers in order to return the
984 * completed request back to the gadget layer.
985 */
986void usb_gadget_giveback_request(struct usb_ep *ep,
987 struct usb_request *req)
988{
989 if (likely(req->status == 0))
990 usb_led_activity(USB_LED_EVENT_GADGET);
991
992 trace_usb_gadget_giveback_request(ep, req, 0);
993
994 req->complete(ep, req);
995}
996EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
997
998/* ------------------------------------------------------------------------- */
999
1000/**
1001 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
1002 * in second parameter or NULL if searched endpoint not found
1003 * @g: controller to check for quirk
1004 * @name: name of searched endpoint
1005 */
1006struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
1007{
1008 struct usb_ep *ep;
1009
1010 gadget_for_each_ep(ep, g) {
1011 if (!strcmp(ep->name, name))
1012 return ep;
1013 }
1014
1015 return NULL;
1016}
1017EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
1018
1019/* ------------------------------------------------------------------------- */
1020
1021int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
1022 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
1023 struct usb_ss_ep_comp_descriptor *ep_comp)
1024{
1025 u8 type;
1026 u16 max;
1027 int num_req_streams = 0;
1028
1029 /* endpoint already claimed? */
1030 if (ep->claimed)
1031 return 0;
1032
1033 type = usb_endpoint_type(desc);
1034 max = usb_endpoint_maxp(desc);
1035
1036 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
1037 return 0;
1038 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
1039 return 0;
1040
1041 if (max > ep->maxpacket_limit)
1042 return 0;
1043
1044 /* "high bandwidth" works only at high speed */
1045 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
1046 return 0;
1047
1048 switch (type) {
1049 case USB_ENDPOINT_XFER_CONTROL:
1050 /* only support ep0 for portable CONTROL traffic */
1051 return 0;
1052 case USB_ENDPOINT_XFER_ISOC:
1053 if (!ep->caps.type_iso)
1054 return 0;
1055 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
1056 if (!gadget_is_dualspeed(gadget) && max > 1023)
1057 return 0;
1058 break;
1059 case USB_ENDPOINT_XFER_BULK:
1060 if (!ep->caps.type_bulk)
1061 return 0;
1062 if (ep_comp && gadget_is_superspeed(gadget)) {
1063 /* Get the number of required streams from the
1064 * EP companion descriptor and see if the EP
1065 * matches it
1066 */
1067 num_req_streams = ep_comp->bmAttributes & 0x1f;
1068 if (num_req_streams > ep->max_streams)
1069 return 0;
1070 }
1071 break;
1072 case USB_ENDPOINT_XFER_INT:
1073 /* Bulk endpoints handle interrupt transfers,
1074 * except the toggle-quirky iso-synch kind
1075 */
1076 if (!ep->caps.type_int && !ep->caps.type_bulk)
1077 return 0;
1078 /* INT: limit 64 bytes full speed, 1024 high/super speed */
1079 if (!gadget_is_dualspeed(gadget) && max > 64)
1080 return 0;
1081 break;
1082 }
1083
1084 return 1;
1085}
1086EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
1087
1088/**
1089 * usb_gadget_check_config - checks if the UDC can support the binded
1090 * configuration
1091 * @gadget: controller to check the USB configuration
1092 *
1093 * Ensure that a UDC is able to support the requested resources by a
1094 * configuration, and that there are no resource limitations, such as
1095 * internal memory allocated to all requested endpoints.
1096 *
1097 * Returns zero on success, else a negative errno.
1098 */
1099int usb_gadget_check_config(struct usb_gadget *gadget)
1100{
1101 if (gadget->ops->check_config)
1102 return gadget->ops->check_config(gadget);
1103 return 0;
1104}
1105EXPORT_SYMBOL_GPL(usb_gadget_check_config);
1106
1107/* ------------------------------------------------------------------------- */
1108
1109static void usb_gadget_state_work(struct work_struct *work)
1110{
1111 struct usb_gadget *gadget = work_to_gadget(work);
1112 struct usb_udc *udc = gadget->udc;
1113
1114 if (udc)
1115 sysfs_notify(&udc->dev.kobj, NULL, "state");
1116}
1117
1118void usb_gadget_set_state(struct usb_gadget *gadget,
1119 enum usb_device_state state)
1120{
1121 gadget->state = state;
1122 schedule_work(&gadget->work);
1123}
1124EXPORT_SYMBOL_GPL(usb_gadget_set_state);
1125
1126/* ------------------------------------------------------------------------- */
1127
1128/* Acquire connect_lock before calling this function. */
1129static int usb_udc_connect_control_locked(struct usb_udc *udc) __must_hold(&udc->connect_lock)
1130{
1131 if (udc->vbus)
1132 return usb_gadget_connect_locked(udc->gadget);
1133 else
1134 return usb_gadget_disconnect_locked(udc->gadget);
1135}
1136
1137static void vbus_event_work(struct work_struct *work)
1138{
1139 struct usb_udc *udc = container_of(work, struct usb_udc, vbus_work);
1140
1141 mutex_lock(&udc->connect_lock);
1142 usb_udc_connect_control_locked(udc);
1143 mutex_unlock(&udc->connect_lock);
1144}
1145
1146/**
1147 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1148 * connect or disconnect gadget
1149 * @gadget: The gadget which vbus change occurs
1150 * @status: The vbus status
1151 *
1152 * The udc driver calls it when it wants to connect or disconnect gadget
1153 * according to vbus status.
1154 *
1155 * This function can be invoked from interrupt context by irq handlers of
1156 * the gadget drivers, however, usb_udc_connect_control() has to run in
1157 * non-atomic context due to the following:
1158 * a. Some of the gadget driver implementations expect the ->pullup
1159 * callback to be invoked in non-atomic context.
1160 * b. usb_gadget_disconnect() acquires udc_lock which is a mutex.
1161 * Hence offload invocation of usb_udc_connect_control() to workqueue.
1162 */
1163void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1164{
1165 struct usb_udc *udc = gadget->udc;
1166
1167 if (udc) {
1168 udc->vbus = status;
1169 schedule_work(&udc->vbus_work);
1170 }
1171}
1172EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1173
1174/**
1175 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1176 * @gadget: The gadget which bus reset occurs
1177 * @driver: The gadget driver we want to notify
1178 *
1179 * If the udc driver has bus reset handler, it needs to call this when the bus
1180 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1181 * well as updates gadget state.
1182 */
1183void usb_gadget_udc_reset(struct usb_gadget *gadget,
1184 struct usb_gadget_driver *driver)
1185{
1186 driver->reset(gadget);
1187 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1188}
1189EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1190
1191/**
1192 * usb_gadget_udc_start_locked - tells usb device controller to start up
1193 * @udc: The UDC to be started
1194 *
1195 * This call is issued by the UDC Class driver when it's about
1196 * to register a gadget driver to the device controller, before
1197 * calling gadget driver's bind() method.
1198 *
1199 * It allows the controller to be powered off until strictly
1200 * necessary to have it powered on.
1201 *
1202 * Returns zero on success, else negative errno.
1203 *
1204 * Caller should acquire connect_lock before invoking this function.
1205 */
1206static inline int usb_gadget_udc_start_locked(struct usb_udc *udc)
1207 __must_hold(&udc->connect_lock)
1208{
1209 int ret;
1210
1211 if (udc->started) {
1212 dev_err(&udc->dev, "UDC had already started\n");
1213 return -EBUSY;
1214 }
1215
1216 ret = udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1217 if (!ret)
1218 udc->started = true;
1219
1220 return ret;
1221}
1222
1223/**
1224 * usb_gadget_udc_stop_locked - tells usb device controller we don't need it anymore
1225 * @udc: The UDC to be stopped
1226 *
1227 * This call is issued by the UDC Class driver after calling
1228 * gadget driver's unbind() method.
1229 *
1230 * The details are implementation specific, but it can go as
1231 * far as powering off UDC completely and disable its data
1232 * line pullups.
1233 *
1234 * Caller should acquire connect lock before invoking this function.
1235 */
1236static inline void usb_gadget_udc_stop_locked(struct usb_udc *udc)
1237 __must_hold(&udc->connect_lock)
1238{
1239 if (!udc->started) {
1240 dev_err(&udc->dev, "UDC had already stopped\n");
1241 return;
1242 }
1243
1244 udc->gadget->ops->udc_stop(udc->gadget);
1245 udc->started = false;
1246}
1247
1248/**
1249 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1250 * current driver
1251 * @udc: The device we want to set maximum speed
1252 * @speed: The maximum speed to allowed to run
1253 *
1254 * This call is issued by the UDC Class driver before calling
1255 * usb_gadget_udc_start() in order to make sure that we don't try to
1256 * connect on speeds the gadget driver doesn't support.
1257 */
1258static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1259 enum usb_device_speed speed)
1260{
1261 struct usb_gadget *gadget = udc->gadget;
1262 enum usb_device_speed s;
1263
1264 if (speed == USB_SPEED_UNKNOWN)
1265 s = gadget->max_speed;
1266 else
1267 s = min(speed, gadget->max_speed);
1268
1269 if (s == USB_SPEED_SUPER_PLUS && gadget->ops->udc_set_ssp_rate)
1270 gadget->ops->udc_set_ssp_rate(gadget, gadget->max_ssp_rate);
1271 else if (gadget->ops->udc_set_speed)
1272 gadget->ops->udc_set_speed(gadget, s);
1273}
1274
1275/**
1276 * usb_gadget_enable_async_callbacks - tell usb device controller to enable asynchronous callbacks
1277 * @udc: The UDC which should enable async callbacks
1278 *
1279 * This routine is used when binding gadget drivers. It undoes the effect
1280 * of usb_gadget_disable_async_callbacks(); the UDC driver should enable IRQs
1281 * (if necessary) and resume issuing callbacks.
1282 *
1283 * This routine will always be called in process context.
1284 */
1285static inline void usb_gadget_enable_async_callbacks(struct usb_udc *udc)
1286{
1287 struct usb_gadget *gadget = udc->gadget;
1288
1289 if (gadget->ops->udc_async_callbacks)
1290 gadget->ops->udc_async_callbacks(gadget, true);
1291}
1292
1293/**
1294 * usb_gadget_disable_async_callbacks - tell usb device controller to disable asynchronous callbacks
1295 * @udc: The UDC which should disable async callbacks
1296 *
1297 * This routine is used when unbinding gadget drivers. It prevents a race:
1298 * The UDC driver doesn't know when the gadget driver's ->unbind callback
1299 * runs, so unless it is told to disable asynchronous callbacks, it might
1300 * issue a callback (such as ->disconnect) after the unbind has completed.
1301 *
1302 * After this function runs, the UDC driver must suppress all ->suspend,
1303 * ->resume, ->disconnect, ->reset, and ->setup callbacks to the gadget driver
1304 * until async callbacks are again enabled. A simple-minded but effective
1305 * way to accomplish this is to tell the UDC hardware not to generate any
1306 * more IRQs.
1307 *
1308 * Request completion callbacks must still be issued. However, it's okay
1309 * to defer them until the request is cancelled, since the pull-up will be
1310 * turned off during the time period when async callbacks are disabled.
1311 *
1312 * This routine will always be called in process context.
1313 */
1314static inline void usb_gadget_disable_async_callbacks(struct usb_udc *udc)
1315{
1316 struct usb_gadget *gadget = udc->gadget;
1317
1318 if (gadget->ops->udc_async_callbacks)
1319 gadget->ops->udc_async_callbacks(gadget, false);
1320}
1321
1322/**
1323 * usb_udc_release - release the usb_udc struct
1324 * @dev: the dev member within usb_udc
1325 *
1326 * This is called by driver's core in order to free memory once the last
1327 * reference is released.
1328 */
1329static void usb_udc_release(struct device *dev)
1330{
1331 struct usb_udc *udc;
1332
1333 udc = container_of(dev, struct usb_udc, dev);
1334 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1335 kfree(udc);
1336}
1337
1338static const struct attribute_group *usb_udc_attr_groups[];
1339
1340static void usb_udc_nop_release(struct device *dev)
1341{
1342 dev_vdbg(dev, "%s\n", __func__);
1343}
1344
1345/**
1346 * usb_initialize_gadget - initialize a gadget and its embedded struct device
1347 * @parent: the parent device to this udc. Usually the controller driver's
1348 * device.
1349 * @gadget: the gadget to be initialized.
1350 * @release: a gadget release function.
1351 */
1352void usb_initialize_gadget(struct device *parent, struct usb_gadget *gadget,
1353 void (*release)(struct device *dev))
1354{
1355 INIT_WORK(&gadget->work, usb_gadget_state_work);
1356 gadget->dev.parent = parent;
1357
1358 if (release)
1359 gadget->dev.release = release;
1360 else
1361 gadget->dev.release = usb_udc_nop_release;
1362
1363 device_initialize(&gadget->dev);
1364 gadget->dev.bus = &gadget_bus_type;
1365}
1366EXPORT_SYMBOL_GPL(usb_initialize_gadget);
1367
1368/**
1369 * usb_add_gadget - adds a new gadget to the udc class driver list
1370 * @gadget: the gadget to be added to the list.
1371 *
1372 * Returns zero on success, negative errno otherwise.
1373 * Does not do a final usb_put_gadget() if an error occurs.
1374 */
1375int usb_add_gadget(struct usb_gadget *gadget)
1376{
1377 struct usb_udc *udc;
1378 int ret = -ENOMEM;
1379
1380 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1381 if (!udc)
1382 goto error;
1383
1384 device_initialize(&udc->dev);
1385 udc->dev.release = usb_udc_release;
1386 udc->dev.class = &udc_class;
1387 udc->dev.groups = usb_udc_attr_groups;
1388 udc->dev.parent = gadget->dev.parent;
1389 ret = dev_set_name(&udc->dev, "%s",
1390 kobject_name(&gadget->dev.parent->kobj));
1391 if (ret)
1392 goto err_put_udc;
1393
1394 udc->gadget = gadget;
1395 gadget->udc = udc;
1396 mutex_init(&udc->connect_lock);
1397
1398 udc->started = false;
1399
1400 mutex_lock(&udc_lock);
1401 list_add_tail(&udc->list, &udc_list);
1402 mutex_unlock(&udc_lock);
1403 INIT_WORK(&udc->vbus_work, vbus_event_work);
1404
1405 ret = device_add(&udc->dev);
1406 if (ret)
1407 goto err_unlist_udc;
1408
1409 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1410 udc->vbus = true;
1411
1412 ret = ida_alloc(&gadget_id_numbers, GFP_KERNEL);
1413 if (ret < 0)
1414 goto err_del_udc;
1415 gadget->id_number = ret;
1416 dev_set_name(&gadget->dev, "gadget.%d", ret);
1417
1418 ret = device_add(&gadget->dev);
1419 if (ret)
1420 goto err_free_id;
1421
1422 return 0;
1423
1424 err_free_id:
1425 ida_free(&gadget_id_numbers, gadget->id_number);
1426
1427 err_del_udc:
1428 flush_work(&gadget->work);
1429 device_del(&udc->dev);
1430
1431 err_unlist_udc:
1432 mutex_lock(&udc_lock);
1433 list_del(&udc->list);
1434 mutex_unlock(&udc_lock);
1435
1436 err_put_udc:
1437 put_device(&udc->dev);
1438
1439 error:
1440 return ret;
1441}
1442EXPORT_SYMBOL_GPL(usb_add_gadget);
1443
1444/**
1445 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1446 * @parent: the parent device to this udc. Usually the controller driver's
1447 * device.
1448 * @gadget: the gadget to be added to the list.
1449 * @release: a gadget release function.
1450 *
1451 * Returns zero on success, negative errno otherwise.
1452 * Calls the gadget release function in the latter case.
1453 */
1454int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1455 void (*release)(struct device *dev))
1456{
1457 int ret;
1458
1459 usb_initialize_gadget(parent, gadget, release);
1460 ret = usb_add_gadget(gadget);
1461 if (ret)
1462 usb_put_gadget(gadget);
1463 return ret;
1464}
1465EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1466
1467/**
1468 * usb_get_gadget_udc_name - get the name of the first UDC controller
1469 * This functions returns the name of the first UDC controller in the system.
1470 * Please note that this interface is usefull only for legacy drivers which
1471 * assume that there is only one UDC controller in the system and they need to
1472 * get its name before initialization. There is no guarantee that the UDC
1473 * of the returned name will be still available, when gadget driver registers
1474 * itself.
1475 *
1476 * Returns pointer to string with UDC controller name on success, NULL
1477 * otherwise. Caller should kfree() returned string.
1478 */
1479char *usb_get_gadget_udc_name(void)
1480{
1481 struct usb_udc *udc;
1482 char *name = NULL;
1483
1484 /* For now we take the first available UDC */
1485 mutex_lock(&udc_lock);
1486 list_for_each_entry(udc, &udc_list, list) {
1487 if (!udc->driver) {
1488 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1489 break;
1490 }
1491 }
1492 mutex_unlock(&udc_lock);
1493 return name;
1494}
1495EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1496
1497/**
1498 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1499 * @parent: the parent device to this udc. Usually the controller
1500 * driver's device.
1501 * @gadget: the gadget to be added to the list
1502 *
1503 * Returns zero on success, negative errno otherwise.
1504 */
1505int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1506{
1507 return usb_add_gadget_udc_release(parent, gadget, NULL);
1508}
1509EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1510
1511/**
1512 * usb_del_gadget - deletes a gadget and unregisters its udc
1513 * @gadget: the gadget to be deleted.
1514 *
1515 * This will unbind @gadget, if it is bound.
1516 * It will not do a final usb_put_gadget().
1517 */
1518void usb_del_gadget(struct usb_gadget *gadget)
1519{
1520 struct usb_udc *udc = gadget->udc;
1521
1522 if (!udc)
1523 return;
1524
1525 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1526
1527 mutex_lock(&udc_lock);
1528 list_del(&udc->list);
1529 mutex_unlock(&udc_lock);
1530
1531 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1532 flush_work(&gadget->work);
1533 device_del(&gadget->dev);
1534 ida_free(&gadget_id_numbers, gadget->id_number);
1535 cancel_work_sync(&udc->vbus_work);
1536 device_unregister(&udc->dev);
1537}
1538EXPORT_SYMBOL_GPL(usb_del_gadget);
1539
1540/**
1541 * usb_del_gadget_udc - unregisters a gadget
1542 * @gadget: the gadget to be unregistered.
1543 *
1544 * Calls usb_del_gadget() and does a final usb_put_gadget().
1545 */
1546void usb_del_gadget_udc(struct usb_gadget *gadget)
1547{
1548 usb_del_gadget(gadget);
1549 usb_put_gadget(gadget);
1550}
1551EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1552
1553/* ------------------------------------------------------------------------- */
1554
1555static int gadget_match_driver(struct device *dev, struct device_driver *drv)
1556{
1557 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1558 struct usb_udc *udc = gadget->udc;
1559 struct usb_gadget_driver *driver = container_of(drv,
1560 struct usb_gadget_driver, driver);
1561
1562 /* If the driver specifies a udc_name, it must match the UDC's name */
1563 if (driver->udc_name &&
1564 strcmp(driver->udc_name, dev_name(&udc->dev)) != 0)
1565 return 0;
1566
1567 /* If the driver is already bound to a gadget, it doesn't match */
1568 if (driver->is_bound)
1569 return 0;
1570
1571 /* Otherwise any gadget driver matches any UDC */
1572 return 1;
1573}
1574
1575static int gadget_bind_driver(struct device *dev)
1576{
1577 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1578 struct usb_udc *udc = gadget->udc;
1579 struct usb_gadget_driver *driver = container_of(dev->driver,
1580 struct usb_gadget_driver, driver);
1581 int ret = 0;
1582
1583 mutex_lock(&udc_lock);
1584 if (driver->is_bound) {
1585 mutex_unlock(&udc_lock);
1586 return -ENXIO; /* Driver binds to only one gadget */
1587 }
1588 driver->is_bound = true;
1589 udc->driver = driver;
1590 mutex_unlock(&udc_lock);
1591
1592 dev_dbg(&udc->dev, "binding gadget driver [%s]\n", driver->function);
1593
1594 usb_gadget_udc_set_speed(udc, driver->max_speed);
1595
1596 ret = driver->bind(udc->gadget, driver);
1597 if (ret)
1598 goto err_bind;
1599
1600 mutex_lock(&udc->connect_lock);
1601 ret = usb_gadget_udc_start_locked(udc);
1602 if (ret) {
1603 mutex_unlock(&udc->connect_lock);
1604 goto err_start;
1605 }
1606 usb_gadget_enable_async_callbacks(udc);
1607 udc->allow_connect = true;
1608 ret = usb_udc_connect_control_locked(udc);
1609 if (ret)
1610 goto err_connect_control;
1611
1612 mutex_unlock(&udc->connect_lock);
1613
1614 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1615 return 0;
1616
1617 err_connect_control:
1618 udc->allow_connect = false;
1619 usb_gadget_disable_async_callbacks(udc);
1620 if (gadget->irq)
1621 synchronize_irq(gadget->irq);
1622 usb_gadget_udc_stop_locked(udc);
1623 mutex_unlock(&udc->connect_lock);
1624
1625 err_start:
1626 driver->unbind(udc->gadget);
1627
1628 err_bind:
1629 if (ret != -EISNAM)
1630 dev_err(&udc->dev, "failed to start %s: %d\n",
1631 driver->function, ret);
1632
1633 mutex_lock(&udc_lock);
1634 udc->driver = NULL;
1635 driver->is_bound = false;
1636 mutex_unlock(&udc_lock);
1637
1638 return ret;
1639}
1640
1641static void gadget_unbind_driver(struct device *dev)
1642{
1643 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1644 struct usb_udc *udc = gadget->udc;
1645 struct usb_gadget_driver *driver = udc->driver;
1646
1647 dev_dbg(&udc->dev, "unbinding gadget driver [%s]\n", driver->function);
1648
1649 udc->allow_connect = false;
1650 cancel_work_sync(&udc->vbus_work);
1651 mutex_lock(&udc->connect_lock);
1652 usb_gadget_disconnect_locked(gadget);
1653 usb_gadget_disable_async_callbacks(udc);
1654 if (gadget->irq)
1655 synchronize_irq(gadget->irq);
1656 mutex_unlock(&udc->connect_lock);
1657
1658 udc->driver->unbind(gadget);
1659
1660 mutex_lock(&udc->connect_lock);
1661 usb_gadget_udc_stop_locked(udc);
1662 mutex_unlock(&udc->connect_lock);
1663
1664 mutex_lock(&udc_lock);
1665 driver->is_bound = false;
1666 udc->driver = NULL;
1667 mutex_unlock(&udc_lock);
1668
1669 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1670}
1671
1672/* ------------------------------------------------------------------------- */
1673
1674int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver,
1675 struct module *owner, const char *mod_name)
1676{
1677 int ret;
1678
1679 if (!driver || !driver->bind || !driver->setup)
1680 return -EINVAL;
1681
1682 driver->driver.bus = &gadget_bus_type;
1683 driver->driver.owner = owner;
1684 driver->driver.mod_name = mod_name;
1685 ret = driver_register(&driver->driver);
1686 if (ret) {
1687 pr_warn("%s: driver registration failed: %d\n",
1688 driver->function, ret);
1689 return ret;
1690 }
1691
1692 mutex_lock(&udc_lock);
1693 if (!driver->is_bound) {
1694 if (driver->match_existing_only) {
1695 pr_warn("%s: couldn't find an available UDC or it's busy\n",
1696 driver->function);
1697 ret = -EBUSY;
1698 } else {
1699 pr_info("%s: couldn't find an available UDC\n",
1700 driver->function);
1701 ret = 0;
1702 }
1703 }
1704 mutex_unlock(&udc_lock);
1705
1706 if (ret)
1707 driver_unregister(&driver->driver);
1708 return ret;
1709}
1710EXPORT_SYMBOL_GPL(usb_gadget_register_driver_owner);
1711
1712int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1713{
1714 if (!driver || !driver->unbind)
1715 return -EINVAL;
1716
1717 driver_unregister(&driver->driver);
1718 return 0;
1719}
1720EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1721
1722/* ------------------------------------------------------------------------- */
1723
1724static ssize_t srp_store(struct device *dev,
1725 struct device_attribute *attr, const char *buf, size_t n)
1726{
1727 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1728
1729 if (sysfs_streq(buf, "1"))
1730 usb_gadget_wakeup(udc->gadget);
1731
1732 return n;
1733}
1734static DEVICE_ATTR_WO(srp);
1735
1736static ssize_t soft_connect_store(struct device *dev,
1737 struct device_attribute *attr, const char *buf, size_t n)
1738{
1739 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1740 ssize_t ret;
1741
1742 device_lock(&udc->gadget->dev);
1743 if (!udc->driver) {
1744 dev_err(dev, "soft-connect without a gadget driver\n");
1745 ret = -EOPNOTSUPP;
1746 goto out;
1747 }
1748
1749 if (sysfs_streq(buf, "connect")) {
1750 mutex_lock(&udc->connect_lock);
1751 usb_gadget_udc_start_locked(udc);
1752 usb_gadget_connect_locked(udc->gadget);
1753 mutex_unlock(&udc->connect_lock);
1754 } else if (sysfs_streq(buf, "disconnect")) {
1755 mutex_lock(&udc->connect_lock);
1756 usb_gadget_disconnect_locked(udc->gadget);
1757 usb_gadget_udc_stop_locked(udc);
1758 mutex_unlock(&udc->connect_lock);
1759 } else {
1760 dev_err(dev, "unsupported command '%s'\n", buf);
1761 ret = -EINVAL;
1762 goto out;
1763 }
1764
1765 ret = n;
1766out:
1767 device_unlock(&udc->gadget->dev);
1768 return ret;
1769}
1770static DEVICE_ATTR_WO(soft_connect);
1771
1772static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1773 char *buf)
1774{
1775 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1776 struct usb_gadget *gadget = udc->gadget;
1777
1778 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1779}
1780static DEVICE_ATTR_RO(state);
1781
1782static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1783 char *buf)
1784{
1785 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1786 struct usb_gadget_driver *drv;
1787 int rc = 0;
1788
1789 mutex_lock(&udc_lock);
1790 drv = udc->driver;
1791 if (drv && drv->function)
1792 rc = scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1793 mutex_unlock(&udc_lock);
1794 return rc;
1795}
1796static DEVICE_ATTR_RO(function);
1797
1798#define USB_UDC_SPEED_ATTR(name, param) \
1799ssize_t name##_show(struct device *dev, \
1800 struct device_attribute *attr, char *buf) \
1801{ \
1802 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1803 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1804 usb_speed_string(udc->gadget->param)); \
1805} \
1806static DEVICE_ATTR_RO(name)
1807
1808static USB_UDC_SPEED_ATTR(current_speed, speed);
1809static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1810
1811#define USB_UDC_ATTR(name) \
1812ssize_t name##_show(struct device *dev, \
1813 struct device_attribute *attr, char *buf) \
1814{ \
1815 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1816 struct usb_gadget *gadget = udc->gadget; \
1817 \
1818 return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1819} \
1820static DEVICE_ATTR_RO(name)
1821
1822static USB_UDC_ATTR(is_otg);
1823static USB_UDC_ATTR(is_a_peripheral);
1824static USB_UDC_ATTR(b_hnp_enable);
1825static USB_UDC_ATTR(a_hnp_support);
1826static USB_UDC_ATTR(a_alt_hnp_support);
1827static USB_UDC_ATTR(is_selfpowered);
1828
1829static struct attribute *usb_udc_attrs[] = {
1830 &dev_attr_srp.attr,
1831 &dev_attr_soft_connect.attr,
1832 &dev_attr_state.attr,
1833 &dev_attr_function.attr,
1834 &dev_attr_current_speed.attr,
1835 &dev_attr_maximum_speed.attr,
1836
1837 &dev_attr_is_otg.attr,
1838 &dev_attr_is_a_peripheral.attr,
1839 &dev_attr_b_hnp_enable.attr,
1840 &dev_attr_a_hnp_support.attr,
1841 &dev_attr_a_alt_hnp_support.attr,
1842 &dev_attr_is_selfpowered.attr,
1843 NULL,
1844};
1845
1846static const struct attribute_group usb_udc_attr_group = {
1847 .attrs = usb_udc_attrs,
1848};
1849
1850static const struct attribute_group *usb_udc_attr_groups[] = {
1851 &usb_udc_attr_group,
1852 NULL,
1853};
1854
1855static int usb_udc_uevent(const struct device *dev, struct kobj_uevent_env *env)
1856{
1857 const struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1858 int ret;
1859
1860 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1861 if (ret) {
1862 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1863 return ret;
1864 }
1865
1866 mutex_lock(&udc_lock);
1867 if (udc->driver)
1868 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1869 udc->driver->function);
1870 mutex_unlock(&udc_lock);
1871 if (ret) {
1872 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1873 return ret;
1874 }
1875
1876 return 0;
1877}
1878
1879static const struct class udc_class = {
1880 .name = "udc",
1881 .dev_uevent = usb_udc_uevent,
1882};
1883
1884static const struct bus_type gadget_bus_type = {
1885 .name = "gadget",
1886 .probe = gadget_bind_driver,
1887 .remove = gadget_unbind_driver,
1888 .match = gadget_match_driver,
1889};
1890
1891static int __init usb_udc_init(void)
1892{
1893 int rc;
1894
1895 rc = class_register(&udc_class);
1896 if (rc)
1897 return rc;
1898
1899 rc = bus_register(&gadget_bus_type);
1900 if (rc)
1901 class_unregister(&udc_class);
1902 return rc;
1903}
1904subsys_initcall(usb_udc_init);
1905
1906static void __exit usb_udc_exit(void)
1907{
1908 bus_unregister(&gadget_bus_type);
1909 class_unregister(&udc_class);
1910}
1911module_exit(usb_udc_exit);
1912
1913MODULE_DESCRIPTION("UDC Framework");
1914MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1915MODULE_LICENSE("GPL v2");