Loading...
Note: File does not exist in v3.1.
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 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 *
41 * This represents the internal data structure which is used by the UDC-class
42 * to hold information about udc driver and gadget together.
43 */
44struct usb_udc {
45 struct usb_gadget_driver *driver;
46 struct usb_gadget *gadget;
47 struct device dev;
48 struct list_head list;
49 bool vbus;
50 bool started;
51};
52
53static struct class *udc_class;
54static LIST_HEAD(udc_list);
55
56/* Protects udc_list, udc->driver, driver->is_bound, and related calls */
57static DEFINE_MUTEX(udc_lock);
58
59/* ------------------------------------------------------------------------- */
60
61/**
62 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
63 * @ep:the endpoint being configured
64 * @maxpacket_limit:value of maximum packet size limit
65 *
66 * This function should be used only in UDC drivers to initialize endpoint
67 * (usually in probe function).
68 */
69void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
70 unsigned maxpacket_limit)
71{
72 ep->maxpacket_limit = maxpacket_limit;
73 ep->maxpacket = maxpacket_limit;
74
75 trace_usb_ep_set_maxpacket_limit(ep, 0);
76}
77EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
78
79/**
80 * usb_ep_enable - configure endpoint, making it usable
81 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
82 * drivers discover endpoints through the ep_list of a usb_gadget.
83 *
84 * When configurations are set, or when interface settings change, the driver
85 * will enable or disable the relevant endpoints. while it is enabled, an
86 * endpoint may be used for i/o until the driver receives a disconnect() from
87 * the host or until the endpoint is disabled.
88 *
89 * the ep0 implementation (which calls this routine) must ensure that the
90 * hardware capabilities of each endpoint match the descriptor provided
91 * for it. for example, an endpoint named "ep2in-bulk" would be usable
92 * for interrupt transfers as well as bulk, but it likely couldn't be used
93 * for iso transfers or for endpoint 14. some endpoints are fully
94 * configurable, with more generic names like "ep-a". (remember that for
95 * USB, "in" means "towards the USB host".)
96 *
97 * This routine may be called in an atomic (interrupt) context.
98 *
99 * returns zero, or a negative error code.
100 */
101int usb_ep_enable(struct usb_ep *ep)
102{
103 int ret = 0;
104
105 if (ep->enabled)
106 goto out;
107
108 /* UDC drivers can't handle endpoints with maxpacket size 0 */
109 if (usb_endpoint_maxp(ep->desc) == 0) {
110 /*
111 * We should log an error message here, but we can't call
112 * dev_err() because there's no way to find the gadget
113 * given only ep.
114 */
115 ret = -EINVAL;
116 goto out;
117 }
118
119 ret = ep->ops->enable(ep, ep->desc);
120 if (ret)
121 goto out;
122
123 ep->enabled = true;
124
125out:
126 trace_usb_ep_enable(ep, ret);
127
128 return ret;
129}
130EXPORT_SYMBOL_GPL(usb_ep_enable);
131
132/**
133 * usb_ep_disable - endpoint is no longer usable
134 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
135 *
136 * no other task may be using this endpoint when this is called.
137 * any pending and uncompleted requests will complete with status
138 * indicating disconnect (-ESHUTDOWN) before this call returns.
139 * gadget drivers must call usb_ep_enable() again before queueing
140 * requests to the endpoint.
141 *
142 * This routine may be called in an atomic (interrupt) context.
143 *
144 * returns zero, or a negative error code.
145 */
146int usb_ep_disable(struct usb_ep *ep)
147{
148 int ret = 0;
149
150 if (!ep->enabled)
151 goto out;
152
153 ret = ep->ops->disable(ep);
154 if (ret)
155 goto out;
156
157 ep->enabled = false;
158
159out:
160 trace_usb_ep_disable(ep, ret);
161
162 return ret;
163}
164EXPORT_SYMBOL_GPL(usb_ep_disable);
165
166/**
167 * usb_ep_alloc_request - allocate a request object to use with this endpoint
168 * @ep:the endpoint to be used with with the request
169 * @gfp_flags:GFP_* flags to use
170 *
171 * Request objects must be allocated with this call, since they normally
172 * need controller-specific setup and may even need endpoint-specific
173 * resources such as allocation of DMA descriptors.
174 * Requests may be submitted with usb_ep_queue(), and receive a single
175 * completion callback. Free requests with usb_ep_free_request(), when
176 * they are no longer needed.
177 *
178 * Returns the request, or null if one could not be allocated.
179 */
180struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
181 gfp_t gfp_flags)
182{
183 struct usb_request *req = NULL;
184
185 req = ep->ops->alloc_request(ep, gfp_flags);
186
187 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
188
189 return req;
190}
191EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
192
193/**
194 * usb_ep_free_request - frees a request object
195 * @ep:the endpoint associated with the request
196 * @req:the request being freed
197 *
198 * Reverses the effect of usb_ep_alloc_request().
199 * Caller guarantees the request is not queued, and that it will
200 * no longer be requeued (or otherwise used).
201 */
202void usb_ep_free_request(struct usb_ep *ep,
203 struct usb_request *req)
204{
205 trace_usb_ep_free_request(ep, req, 0);
206 ep->ops->free_request(ep, req);
207}
208EXPORT_SYMBOL_GPL(usb_ep_free_request);
209
210/**
211 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
212 * @ep:the endpoint associated with the request
213 * @req:the request being submitted
214 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
215 * pre-allocate all necessary memory with the request.
216 *
217 * This tells the device controller to perform the specified request through
218 * that endpoint (reading or writing a buffer). When the request completes,
219 * including being canceled by usb_ep_dequeue(), the request's completion
220 * routine is called to return the request to the driver. Any endpoint
221 * (except control endpoints like ep0) may have more than one transfer
222 * request queued; they complete in FIFO order. Once a gadget driver
223 * submits a request, that request may not be examined or modified until it
224 * is given back to that driver through the completion callback.
225 *
226 * Each request is turned into one or more packets. The controller driver
227 * never merges adjacent requests into the same packet. OUT transfers
228 * will sometimes use data that's already buffered in the hardware.
229 * Drivers can rely on the fact that the first byte of the request's buffer
230 * always corresponds to the first byte of some USB packet, for both
231 * IN and OUT transfers.
232 *
233 * Bulk endpoints can queue any amount of data; the transfer is packetized
234 * automatically. The last packet will be short if the request doesn't fill it
235 * out completely. Zero length packets (ZLPs) should be avoided in portable
236 * protocols since not all usb hardware can successfully handle zero length
237 * packets. (ZLPs may be explicitly written, and may be implicitly written if
238 * the request 'zero' flag is set.) Bulk endpoints may also be used
239 * for interrupt transfers; but the reverse is not true, and some endpoints
240 * won't support every interrupt transfer. (Such as 768 byte packets.)
241 *
242 * Interrupt-only endpoints are less functional than bulk endpoints, for
243 * example by not supporting queueing or not handling buffers that are
244 * larger than the endpoint's maxpacket size. They may also treat data
245 * toggle differently.
246 *
247 * Control endpoints ... after getting a setup() callback, the driver queues
248 * one response (even if it would be zero length). That enables the
249 * status ack, after transferring data as specified in the response. Setup
250 * functions may return negative error codes to generate protocol stalls.
251 * (Note that some USB device controllers disallow protocol stall responses
252 * in some cases.) When control responses are deferred (the response is
253 * written after the setup callback returns), then usb_ep_set_halt() may be
254 * used on ep0 to trigger protocol stalls. Depending on the controller,
255 * it may not be possible to trigger a status-stage protocol stall when the
256 * data stage is over, that is, from within the response's completion
257 * routine.
258 *
259 * For periodic endpoints, like interrupt or isochronous ones, the usb host
260 * arranges to poll once per interval, and the gadget driver usually will
261 * have queued some data to transfer at that time.
262 *
263 * Note that @req's ->complete() callback must never be called from
264 * within usb_ep_queue() as that can create deadlock situations.
265 *
266 * This routine may be called in interrupt context.
267 *
268 * Returns zero, or a negative error code. Endpoints that are not enabled
269 * report errors; errors will also be
270 * reported when the usb peripheral is disconnected.
271 *
272 * If and only if @req is successfully queued (the return value is zero),
273 * @req->complete() will be called exactly once, when the Gadget core and
274 * UDC are finished with the request. When the completion function is called,
275 * control of the request is returned to the device driver which submitted it.
276 * The completion handler may then immediately free or reuse @req.
277 */
278int usb_ep_queue(struct usb_ep *ep,
279 struct usb_request *req, gfp_t gfp_flags)
280{
281 int ret = 0;
282
283 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
284 ret = -ESHUTDOWN;
285 goto out;
286 }
287
288 ret = ep->ops->queue(ep, req, gfp_flags);
289
290out:
291 trace_usb_ep_queue(ep, req, ret);
292
293 return ret;
294}
295EXPORT_SYMBOL_GPL(usb_ep_queue);
296
297/**
298 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
299 * @ep:the endpoint associated with the request
300 * @req:the request being canceled
301 *
302 * If the request is still active on the endpoint, it is dequeued and
303 * eventually its completion routine is called (with status -ECONNRESET);
304 * else a negative error code is returned. This routine is asynchronous,
305 * that is, it may return before the completion routine runs.
306 *
307 * Note that some hardware can't clear out write fifos (to unlink the request
308 * at the head of the queue) except as part of disconnecting from usb. Such
309 * restrictions prevent drivers from supporting configuration changes,
310 * even to configuration zero (a "chapter 9" requirement).
311 *
312 * This routine may be called in interrupt context.
313 */
314int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
315{
316 int ret;
317
318 ret = ep->ops->dequeue(ep, req);
319 trace_usb_ep_dequeue(ep, req, ret);
320
321 return ret;
322}
323EXPORT_SYMBOL_GPL(usb_ep_dequeue);
324
325/**
326 * usb_ep_set_halt - sets the endpoint halt feature.
327 * @ep: the non-isochronous endpoint being stalled
328 *
329 * Use this to stall an endpoint, perhaps as an error report.
330 * Except for control endpoints,
331 * the endpoint stays halted (will not stream any data) until the host
332 * clears this feature; drivers may need to empty the endpoint's request
333 * queue first, to make sure no inappropriate transfers happen.
334 *
335 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
336 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
337 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
338 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
339 *
340 * This routine may be called in interrupt context.
341 *
342 * Returns zero, or a negative error code. On success, this call sets
343 * underlying hardware state that blocks data transfers.
344 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
345 * transfer requests are still queued, or if the controller hardware
346 * (usually a FIFO) still holds bytes that the host hasn't collected.
347 */
348int usb_ep_set_halt(struct usb_ep *ep)
349{
350 int ret;
351
352 ret = ep->ops->set_halt(ep, 1);
353 trace_usb_ep_set_halt(ep, ret);
354
355 return ret;
356}
357EXPORT_SYMBOL_GPL(usb_ep_set_halt);
358
359/**
360 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
361 * @ep:the bulk or interrupt endpoint being reset
362 *
363 * Use this when responding to the standard usb "set interface" request,
364 * for endpoints that aren't reconfigured, after clearing any other state
365 * in the endpoint's i/o queue.
366 *
367 * This routine may be called in interrupt context.
368 *
369 * Returns zero, or a negative error code. On success, this call clears
370 * the underlying hardware state reflecting endpoint halt and data toggle.
371 * Note that some hardware can't support this request (like pxa2xx_udc),
372 * and accordingly can't correctly implement interface altsettings.
373 */
374int usb_ep_clear_halt(struct usb_ep *ep)
375{
376 int ret;
377
378 ret = ep->ops->set_halt(ep, 0);
379 trace_usb_ep_clear_halt(ep, ret);
380
381 return ret;
382}
383EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
384
385/**
386 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
387 * @ep: the endpoint being wedged
388 *
389 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
390 * requests. If the gadget driver clears the halt status, it will
391 * automatically unwedge the endpoint.
392 *
393 * This routine may be called in interrupt context.
394 *
395 * Returns zero on success, else negative errno.
396 */
397int usb_ep_set_wedge(struct usb_ep *ep)
398{
399 int ret;
400
401 if (ep->ops->set_wedge)
402 ret = ep->ops->set_wedge(ep);
403 else
404 ret = ep->ops->set_halt(ep, 1);
405
406 trace_usb_ep_set_wedge(ep, ret);
407
408 return ret;
409}
410EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
411
412/**
413 * usb_ep_fifo_status - returns number of bytes in fifo, or error
414 * @ep: the endpoint whose fifo status is being checked.
415 *
416 * FIFO endpoints may have "unclaimed data" in them in certain cases,
417 * such as after aborted transfers. Hosts may not have collected all
418 * the IN data written by the gadget driver (and reported by a request
419 * completion). The gadget driver may not have collected all the data
420 * written OUT to it by the host. Drivers that need precise handling for
421 * fault reporting or recovery may need to use this call.
422 *
423 * This routine may be called in interrupt context.
424 *
425 * This returns the number of such bytes in the fifo, or a negative
426 * errno if the endpoint doesn't use a FIFO or doesn't support such
427 * precise handling.
428 */
429int usb_ep_fifo_status(struct usb_ep *ep)
430{
431 int ret;
432
433 if (ep->ops->fifo_status)
434 ret = ep->ops->fifo_status(ep);
435 else
436 ret = -EOPNOTSUPP;
437
438 trace_usb_ep_fifo_status(ep, ret);
439
440 return ret;
441}
442EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
443
444/**
445 * usb_ep_fifo_flush - flushes contents of a fifo
446 * @ep: the endpoint whose fifo is being flushed.
447 *
448 * This call may be used to flush the "unclaimed data" that may exist in
449 * an endpoint fifo after abnormal transaction terminations. The call
450 * must never be used except when endpoint is not being used for any
451 * protocol translation.
452 *
453 * This routine may be called in interrupt context.
454 */
455void usb_ep_fifo_flush(struct usb_ep *ep)
456{
457 if (ep->ops->fifo_flush)
458 ep->ops->fifo_flush(ep);
459
460 trace_usb_ep_fifo_flush(ep, 0);
461}
462EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
463
464/* ------------------------------------------------------------------------- */
465
466/**
467 * usb_gadget_frame_number - returns the current frame number
468 * @gadget: controller that reports the frame number
469 *
470 * Returns the usb frame number, normally eleven bits from a SOF packet,
471 * or negative errno if this device doesn't support this capability.
472 */
473int usb_gadget_frame_number(struct usb_gadget *gadget)
474{
475 int ret;
476
477 ret = gadget->ops->get_frame(gadget);
478
479 trace_usb_gadget_frame_number(gadget, ret);
480
481 return ret;
482}
483EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
484
485/**
486 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
487 * @gadget: controller used to wake up the host
488 *
489 * Returns zero on success, else negative error code if the hardware
490 * doesn't support such attempts, or its support has not been enabled
491 * by the usb host. Drivers must return device descriptors that report
492 * their ability to support this, or hosts won't enable it.
493 *
494 * This may also try to use SRP to wake the host and start enumeration,
495 * even if OTG isn't otherwise in use. OTG devices may also start
496 * remote wakeup even when hosts don't explicitly enable it.
497 */
498int usb_gadget_wakeup(struct usb_gadget *gadget)
499{
500 int ret = 0;
501
502 if (!gadget->ops->wakeup) {
503 ret = -EOPNOTSUPP;
504 goto out;
505 }
506
507 ret = gadget->ops->wakeup(gadget);
508
509out:
510 trace_usb_gadget_wakeup(gadget, ret);
511
512 return ret;
513}
514EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
515
516/**
517 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
518 * @gadget:the device being declared as self-powered
519 *
520 * this affects the device status reported by the hardware driver
521 * to reflect that it now has a local power supply.
522 *
523 * returns zero on success, else negative errno.
524 */
525int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
526{
527 int ret = 0;
528
529 if (!gadget->ops->set_selfpowered) {
530 ret = -EOPNOTSUPP;
531 goto out;
532 }
533
534 ret = gadget->ops->set_selfpowered(gadget, 1);
535
536out:
537 trace_usb_gadget_set_selfpowered(gadget, ret);
538
539 return ret;
540}
541EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
542
543/**
544 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
545 * @gadget:the device being declared as bus-powered
546 *
547 * this affects the device status reported by the hardware driver.
548 * some hardware may not support bus-powered operation, in which
549 * case this feature's value can never change.
550 *
551 * returns zero on success, else negative errno.
552 */
553int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
554{
555 int ret = 0;
556
557 if (!gadget->ops->set_selfpowered) {
558 ret = -EOPNOTSUPP;
559 goto out;
560 }
561
562 ret = gadget->ops->set_selfpowered(gadget, 0);
563
564out:
565 trace_usb_gadget_clear_selfpowered(gadget, ret);
566
567 return ret;
568}
569EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
570
571/**
572 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
573 * @gadget:The device which now has VBUS power.
574 * Context: can sleep
575 *
576 * This call is used by a driver for an external transceiver (or GPIO)
577 * that detects a VBUS power session starting. Common responses include
578 * resuming the controller, activating the D+ (or D-) pullup to let the
579 * host detect that a USB device is attached, and starting to draw power
580 * (8mA or possibly more, especially after SET_CONFIGURATION).
581 *
582 * Returns zero on success, else negative errno.
583 */
584int usb_gadget_vbus_connect(struct usb_gadget *gadget)
585{
586 int ret = 0;
587
588 if (!gadget->ops->vbus_session) {
589 ret = -EOPNOTSUPP;
590 goto out;
591 }
592
593 ret = gadget->ops->vbus_session(gadget, 1);
594
595out:
596 trace_usb_gadget_vbus_connect(gadget, ret);
597
598 return ret;
599}
600EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
601
602/**
603 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
604 * @gadget:The device whose VBUS usage is being described
605 * @mA:How much current to draw, in milliAmperes. This should be twice
606 * the value listed in the configuration descriptor bMaxPower field.
607 *
608 * This call is used by gadget drivers during SET_CONFIGURATION calls,
609 * reporting how much power the device may consume. For example, this
610 * could affect how quickly batteries are recharged.
611 *
612 * Returns zero on success, else negative errno.
613 */
614int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
615{
616 int ret = 0;
617
618 if (!gadget->ops->vbus_draw) {
619 ret = -EOPNOTSUPP;
620 goto out;
621 }
622
623 ret = gadget->ops->vbus_draw(gadget, mA);
624 if (!ret)
625 gadget->mA = mA;
626
627out:
628 trace_usb_gadget_vbus_draw(gadget, ret);
629
630 return ret;
631}
632EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
633
634/**
635 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
636 * @gadget:the device whose VBUS supply is being described
637 * Context: can sleep
638 *
639 * This call is used by a driver for an external transceiver (or GPIO)
640 * that detects a VBUS power session ending. Common responses include
641 * reversing everything done in usb_gadget_vbus_connect().
642 *
643 * Returns zero on success, else negative errno.
644 */
645int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
646{
647 int ret = 0;
648
649 if (!gadget->ops->vbus_session) {
650 ret = -EOPNOTSUPP;
651 goto out;
652 }
653
654 ret = gadget->ops->vbus_session(gadget, 0);
655
656out:
657 trace_usb_gadget_vbus_disconnect(gadget, ret);
658
659 return ret;
660}
661EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
662
663/**
664 * usb_gadget_connect - software-controlled connect to USB host
665 * @gadget:the peripheral being connected
666 *
667 * Enables the D+ (or potentially D-) pullup. The host will start
668 * enumerating this gadget when the pullup is active and a VBUS session
669 * is active (the link is powered).
670 *
671 * Returns zero on success, else negative errno.
672 */
673int usb_gadget_connect(struct usb_gadget *gadget)
674{
675 int ret = 0;
676
677 if (!gadget->ops->pullup) {
678 ret = -EOPNOTSUPP;
679 goto out;
680 }
681
682 if (gadget->deactivated) {
683 /*
684 * If gadget is deactivated we only save new state.
685 * Gadget will be connected automatically after activation.
686 */
687 gadget->connected = true;
688 goto out;
689 }
690
691 ret = gadget->ops->pullup(gadget, 1);
692 if (!ret)
693 gadget->connected = 1;
694
695out:
696 trace_usb_gadget_connect(gadget, ret);
697
698 return ret;
699}
700EXPORT_SYMBOL_GPL(usb_gadget_connect);
701
702/**
703 * usb_gadget_disconnect - software-controlled disconnect from USB host
704 * @gadget:the peripheral being disconnected
705 *
706 * Disables the D+ (or potentially D-) pullup, which the host may see
707 * as a disconnect (when a VBUS session is active). Not all systems
708 * support software pullup controls.
709 *
710 * Following a successful disconnect, invoke the ->disconnect() callback
711 * for the current gadget driver so that UDC drivers don't need to.
712 *
713 * Returns zero on success, else negative errno.
714 */
715int usb_gadget_disconnect(struct usb_gadget *gadget)
716{
717 int ret = 0;
718
719 if (!gadget->ops->pullup) {
720 ret = -EOPNOTSUPP;
721 goto out;
722 }
723
724 if (!gadget->connected)
725 goto out;
726
727 if (gadget->deactivated) {
728 /*
729 * If gadget is deactivated we only save new state.
730 * Gadget will stay disconnected after activation.
731 */
732 gadget->connected = false;
733 goto out;
734 }
735
736 ret = gadget->ops->pullup(gadget, 0);
737 if (!ret)
738 gadget->connected = 0;
739
740 mutex_lock(&udc_lock);
741 if (gadget->udc->driver)
742 gadget->udc->driver->disconnect(gadget);
743 mutex_unlock(&udc_lock);
744
745out:
746 trace_usb_gadget_disconnect(gadget, ret);
747
748 return ret;
749}
750EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
751
752/**
753 * usb_gadget_deactivate - deactivate function which is not ready to work
754 * @gadget: the peripheral being deactivated
755 *
756 * This routine may be used during the gadget driver bind() call to prevent
757 * the peripheral from ever being visible to the USB host, unless later
758 * usb_gadget_activate() is called. For example, user mode components may
759 * need to be activated before the system can talk to hosts.
760 *
761 * Returns zero on success, else negative errno.
762 */
763int usb_gadget_deactivate(struct usb_gadget *gadget)
764{
765 int ret = 0;
766
767 if (gadget->deactivated)
768 goto out;
769
770 if (gadget->connected) {
771 ret = usb_gadget_disconnect(gadget);
772 if (ret)
773 goto out;
774
775 /*
776 * If gadget was being connected before deactivation, we want
777 * to reconnect it in usb_gadget_activate().
778 */
779 gadget->connected = true;
780 }
781 gadget->deactivated = true;
782
783out:
784 trace_usb_gadget_deactivate(gadget, ret);
785
786 return ret;
787}
788EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
789
790/**
791 * usb_gadget_activate - activate function which is not ready to work
792 * @gadget: the peripheral being activated
793 *
794 * This routine activates gadget which was previously deactivated with
795 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
796 *
797 * Returns zero on success, else negative errno.
798 */
799int usb_gadget_activate(struct usb_gadget *gadget)
800{
801 int ret = 0;
802
803 if (!gadget->deactivated)
804 goto out;
805
806 gadget->deactivated = false;
807
808 /*
809 * If gadget has been connected before deactivation, or became connected
810 * while it was being deactivated, we call usb_gadget_connect().
811 */
812 if (gadget->connected)
813 ret = usb_gadget_connect(gadget);
814
815out:
816 trace_usb_gadget_activate(gadget, ret);
817
818 return ret;
819}
820EXPORT_SYMBOL_GPL(usb_gadget_activate);
821
822/* ------------------------------------------------------------------------- */
823
824#ifdef CONFIG_HAS_DMA
825
826int usb_gadget_map_request_by_dev(struct device *dev,
827 struct usb_request *req, int is_in)
828{
829 if (req->length == 0)
830 return 0;
831
832 if (req->num_sgs) {
833 int mapped;
834
835 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
836 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
837 if (mapped == 0) {
838 dev_err(dev, "failed to map SGs\n");
839 return -EFAULT;
840 }
841
842 req->num_mapped_sgs = mapped;
843 } else {
844 if (is_vmalloc_addr(req->buf)) {
845 dev_err(dev, "buffer is not dma capable\n");
846 return -EFAULT;
847 } else if (object_is_on_stack(req->buf)) {
848 dev_err(dev, "buffer is on stack\n");
849 return -EFAULT;
850 }
851
852 req->dma = dma_map_single(dev, req->buf, req->length,
853 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
854
855 if (dma_mapping_error(dev, req->dma)) {
856 dev_err(dev, "failed to map buffer\n");
857 return -EFAULT;
858 }
859
860 req->dma_mapped = 1;
861 }
862
863 return 0;
864}
865EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
866
867int usb_gadget_map_request(struct usb_gadget *gadget,
868 struct usb_request *req, int is_in)
869{
870 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
871}
872EXPORT_SYMBOL_GPL(usb_gadget_map_request);
873
874void usb_gadget_unmap_request_by_dev(struct device *dev,
875 struct usb_request *req, int is_in)
876{
877 if (req->length == 0)
878 return;
879
880 if (req->num_mapped_sgs) {
881 dma_unmap_sg(dev, req->sg, req->num_sgs,
882 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
883
884 req->num_mapped_sgs = 0;
885 } else if (req->dma_mapped) {
886 dma_unmap_single(dev, req->dma, req->length,
887 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
888 req->dma_mapped = 0;
889 }
890}
891EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
892
893void usb_gadget_unmap_request(struct usb_gadget *gadget,
894 struct usb_request *req, int is_in)
895{
896 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
897}
898EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
899
900#endif /* CONFIG_HAS_DMA */
901
902/* ------------------------------------------------------------------------- */
903
904/**
905 * usb_gadget_giveback_request - give the request back to the gadget layer
906 * @ep: the endpoint to be used with with the request
907 * @req: the request being given back
908 *
909 * This is called by device controller drivers in order to return the
910 * completed request back to the gadget layer.
911 */
912void usb_gadget_giveback_request(struct usb_ep *ep,
913 struct usb_request *req)
914{
915 if (likely(req->status == 0))
916 usb_led_activity(USB_LED_EVENT_GADGET);
917
918 trace_usb_gadget_giveback_request(ep, req, 0);
919
920 req->complete(ep, req);
921}
922EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
923
924/* ------------------------------------------------------------------------- */
925
926/**
927 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
928 * in second parameter or NULL if searched endpoint not found
929 * @g: controller to check for quirk
930 * @name: name of searched endpoint
931 */
932struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
933{
934 struct usb_ep *ep;
935
936 gadget_for_each_ep(ep, g) {
937 if (!strcmp(ep->name, name))
938 return ep;
939 }
940
941 return NULL;
942}
943EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
944
945/* ------------------------------------------------------------------------- */
946
947int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
948 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
949 struct usb_ss_ep_comp_descriptor *ep_comp)
950{
951 u8 type;
952 u16 max;
953 int num_req_streams = 0;
954
955 /* endpoint already claimed? */
956 if (ep->claimed)
957 return 0;
958
959 type = usb_endpoint_type(desc);
960 max = usb_endpoint_maxp(desc);
961
962 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
963 return 0;
964 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
965 return 0;
966
967 if (max > ep->maxpacket_limit)
968 return 0;
969
970 /* "high bandwidth" works only at high speed */
971 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
972 return 0;
973
974 switch (type) {
975 case USB_ENDPOINT_XFER_CONTROL:
976 /* only support ep0 for portable CONTROL traffic */
977 return 0;
978 case USB_ENDPOINT_XFER_ISOC:
979 if (!ep->caps.type_iso)
980 return 0;
981 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
982 if (!gadget_is_dualspeed(gadget) && max > 1023)
983 return 0;
984 break;
985 case USB_ENDPOINT_XFER_BULK:
986 if (!ep->caps.type_bulk)
987 return 0;
988 if (ep_comp && gadget_is_superspeed(gadget)) {
989 /* Get the number of required streams from the
990 * EP companion descriptor and see if the EP
991 * matches it
992 */
993 num_req_streams = ep_comp->bmAttributes & 0x1f;
994 if (num_req_streams > ep->max_streams)
995 return 0;
996 }
997 break;
998 case USB_ENDPOINT_XFER_INT:
999 /* Bulk endpoints handle interrupt transfers,
1000 * except the toggle-quirky iso-synch kind
1001 */
1002 if (!ep->caps.type_int && !ep->caps.type_bulk)
1003 return 0;
1004 /* INT: limit 64 bytes full speed, 1024 high/super speed */
1005 if (!gadget_is_dualspeed(gadget) && max > 64)
1006 return 0;
1007 break;
1008 }
1009
1010 return 1;
1011}
1012EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
1013
1014/**
1015 * usb_gadget_check_config - checks if the UDC can support the binded
1016 * configuration
1017 * @gadget: controller to check the USB configuration
1018 *
1019 * Ensure that a UDC is able to support the requested resources by a
1020 * configuration, and that there are no resource limitations, such as
1021 * internal memory allocated to all requested endpoints.
1022 *
1023 * Returns zero on success, else a negative errno.
1024 */
1025int usb_gadget_check_config(struct usb_gadget *gadget)
1026{
1027 if (gadget->ops->check_config)
1028 return gadget->ops->check_config(gadget);
1029 return 0;
1030}
1031EXPORT_SYMBOL_GPL(usb_gadget_check_config);
1032
1033/* ------------------------------------------------------------------------- */
1034
1035static void usb_gadget_state_work(struct work_struct *work)
1036{
1037 struct usb_gadget *gadget = work_to_gadget(work);
1038 struct usb_udc *udc = gadget->udc;
1039
1040 if (udc)
1041 sysfs_notify(&udc->dev.kobj, NULL, "state");
1042}
1043
1044void usb_gadget_set_state(struct usb_gadget *gadget,
1045 enum usb_device_state state)
1046{
1047 gadget->state = state;
1048 schedule_work(&gadget->work);
1049}
1050EXPORT_SYMBOL_GPL(usb_gadget_set_state);
1051
1052/* ------------------------------------------------------------------------- */
1053
1054static void usb_udc_connect_control(struct usb_udc *udc)
1055{
1056 if (udc->vbus)
1057 usb_gadget_connect(udc->gadget);
1058 else
1059 usb_gadget_disconnect(udc->gadget);
1060}
1061
1062/**
1063 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1064 * connect or disconnect gadget
1065 * @gadget: The gadget which vbus change occurs
1066 * @status: The vbus status
1067 *
1068 * The udc driver calls it when it wants to connect or disconnect gadget
1069 * according to vbus status.
1070 */
1071void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1072{
1073 struct usb_udc *udc = gadget->udc;
1074
1075 if (udc) {
1076 udc->vbus = status;
1077 usb_udc_connect_control(udc);
1078 }
1079}
1080EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1081
1082/**
1083 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1084 * @gadget: The gadget which bus reset occurs
1085 * @driver: The gadget driver we want to notify
1086 *
1087 * If the udc driver has bus reset handler, it needs to call this when the bus
1088 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1089 * well as updates gadget state.
1090 */
1091void usb_gadget_udc_reset(struct usb_gadget *gadget,
1092 struct usb_gadget_driver *driver)
1093{
1094 driver->reset(gadget);
1095 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1096}
1097EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1098
1099/**
1100 * usb_gadget_udc_start - tells usb device controller to start up
1101 * @udc: The UDC to be started
1102 *
1103 * This call is issued by the UDC Class driver when it's about
1104 * to register a gadget driver to the device controller, before
1105 * calling gadget driver's bind() method.
1106 *
1107 * It allows the controller to be powered off until strictly
1108 * necessary to have it powered on.
1109 *
1110 * Returns zero on success, else negative errno.
1111 */
1112static inline int usb_gadget_udc_start(struct usb_udc *udc)
1113{
1114 int ret;
1115
1116 if (udc->started) {
1117 dev_err(&udc->dev, "UDC had already started\n");
1118 return -EBUSY;
1119 }
1120
1121 ret = udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1122 if (!ret)
1123 udc->started = true;
1124
1125 return ret;
1126}
1127
1128/**
1129 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
1130 * @udc: The UDC to be stopped
1131 *
1132 * This call is issued by the UDC Class driver after calling
1133 * gadget driver's unbind() method.
1134 *
1135 * The details are implementation specific, but it can go as
1136 * far as powering off UDC completely and disable its data
1137 * line pullups.
1138 */
1139static inline void usb_gadget_udc_stop(struct usb_udc *udc)
1140{
1141 if (!udc->started) {
1142 dev_err(&udc->dev, "UDC had already stopped\n");
1143 return;
1144 }
1145
1146 udc->gadget->ops->udc_stop(udc->gadget);
1147 udc->started = false;
1148}
1149
1150/**
1151 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1152 * current driver
1153 * @udc: The device we want to set maximum speed
1154 * @speed: The maximum speed to allowed to run
1155 *
1156 * This call is issued by the UDC Class driver before calling
1157 * usb_gadget_udc_start() in order to make sure that we don't try to
1158 * connect on speeds the gadget driver doesn't support.
1159 */
1160static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1161 enum usb_device_speed speed)
1162{
1163 struct usb_gadget *gadget = udc->gadget;
1164 enum usb_device_speed s;
1165
1166 if (speed == USB_SPEED_UNKNOWN)
1167 s = gadget->max_speed;
1168 else
1169 s = min(speed, gadget->max_speed);
1170
1171 if (s == USB_SPEED_SUPER_PLUS && gadget->ops->udc_set_ssp_rate)
1172 gadget->ops->udc_set_ssp_rate(gadget, gadget->max_ssp_rate);
1173 else if (gadget->ops->udc_set_speed)
1174 gadget->ops->udc_set_speed(gadget, s);
1175}
1176
1177/**
1178 * usb_gadget_enable_async_callbacks - tell usb device controller to enable asynchronous callbacks
1179 * @udc: The UDC which should enable async callbacks
1180 *
1181 * This routine is used when binding gadget drivers. It undoes the effect
1182 * of usb_gadget_disable_async_callbacks(); the UDC driver should enable IRQs
1183 * (if necessary) and resume issuing callbacks.
1184 *
1185 * This routine will always be called in process context.
1186 */
1187static inline void usb_gadget_enable_async_callbacks(struct usb_udc *udc)
1188{
1189 struct usb_gadget *gadget = udc->gadget;
1190
1191 if (gadget->ops->udc_async_callbacks)
1192 gadget->ops->udc_async_callbacks(gadget, true);
1193}
1194
1195/**
1196 * usb_gadget_disable_async_callbacks - tell usb device controller to disable asynchronous callbacks
1197 * @udc: The UDC which should disable async callbacks
1198 *
1199 * This routine is used when unbinding gadget drivers. It prevents a race:
1200 * The UDC driver doesn't know when the gadget driver's ->unbind callback
1201 * runs, so unless it is told to disable asynchronous callbacks, it might
1202 * issue a callback (such as ->disconnect) after the unbind has completed.
1203 *
1204 * After this function runs, the UDC driver must suppress all ->suspend,
1205 * ->resume, ->disconnect, ->reset, and ->setup callbacks to the gadget driver
1206 * until async callbacks are again enabled. A simple-minded but effective
1207 * way to accomplish this is to tell the UDC hardware not to generate any
1208 * more IRQs.
1209 *
1210 * Request completion callbacks must still be issued. However, it's okay
1211 * to defer them until the request is cancelled, since the pull-up will be
1212 * turned off during the time period when async callbacks are disabled.
1213 *
1214 * This routine will always be called in process context.
1215 */
1216static inline void usb_gadget_disable_async_callbacks(struct usb_udc *udc)
1217{
1218 struct usb_gadget *gadget = udc->gadget;
1219
1220 if (gadget->ops->udc_async_callbacks)
1221 gadget->ops->udc_async_callbacks(gadget, false);
1222}
1223
1224/**
1225 * usb_udc_release - release the usb_udc struct
1226 * @dev: the dev member within usb_udc
1227 *
1228 * This is called by driver's core in order to free memory once the last
1229 * reference is released.
1230 */
1231static void usb_udc_release(struct device *dev)
1232{
1233 struct usb_udc *udc;
1234
1235 udc = container_of(dev, struct usb_udc, dev);
1236 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1237 kfree(udc);
1238}
1239
1240static const struct attribute_group *usb_udc_attr_groups[];
1241
1242static void usb_udc_nop_release(struct device *dev)
1243{
1244 dev_vdbg(dev, "%s\n", __func__);
1245}
1246
1247/**
1248 * usb_initialize_gadget - initialize a gadget and its embedded struct device
1249 * @parent: the parent device to this udc. Usually the controller driver's
1250 * device.
1251 * @gadget: the gadget to be initialized.
1252 * @release: a gadget release function.
1253 */
1254void usb_initialize_gadget(struct device *parent, struct usb_gadget *gadget,
1255 void (*release)(struct device *dev))
1256{
1257 INIT_WORK(&gadget->work, usb_gadget_state_work);
1258 gadget->dev.parent = parent;
1259
1260 if (release)
1261 gadget->dev.release = release;
1262 else
1263 gadget->dev.release = usb_udc_nop_release;
1264
1265 device_initialize(&gadget->dev);
1266 gadget->dev.bus = &gadget_bus_type;
1267}
1268EXPORT_SYMBOL_GPL(usb_initialize_gadget);
1269
1270/**
1271 * usb_add_gadget - adds a new gadget to the udc class driver list
1272 * @gadget: the gadget to be added to the list.
1273 *
1274 * Returns zero on success, negative errno otherwise.
1275 * Does not do a final usb_put_gadget() if an error occurs.
1276 */
1277int usb_add_gadget(struct usb_gadget *gadget)
1278{
1279 struct usb_udc *udc;
1280 int ret = -ENOMEM;
1281
1282 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1283 if (!udc)
1284 goto error;
1285
1286 device_initialize(&udc->dev);
1287 udc->dev.release = usb_udc_release;
1288 udc->dev.class = udc_class;
1289 udc->dev.groups = usb_udc_attr_groups;
1290 udc->dev.parent = gadget->dev.parent;
1291 ret = dev_set_name(&udc->dev, "%s",
1292 kobject_name(&gadget->dev.parent->kobj));
1293 if (ret)
1294 goto err_put_udc;
1295
1296 udc->gadget = gadget;
1297 gadget->udc = udc;
1298
1299 udc->started = false;
1300
1301 mutex_lock(&udc_lock);
1302 list_add_tail(&udc->list, &udc_list);
1303 mutex_unlock(&udc_lock);
1304
1305 ret = device_add(&udc->dev);
1306 if (ret)
1307 goto err_unlist_udc;
1308
1309 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1310 udc->vbus = true;
1311
1312 ret = ida_alloc(&gadget_id_numbers, GFP_KERNEL);
1313 if (ret < 0)
1314 goto err_del_udc;
1315 gadget->id_number = ret;
1316 dev_set_name(&gadget->dev, "gadget.%d", ret);
1317
1318 ret = device_add(&gadget->dev);
1319 if (ret)
1320 goto err_free_id;
1321
1322 return 0;
1323
1324 err_free_id:
1325 ida_free(&gadget_id_numbers, gadget->id_number);
1326
1327 err_del_udc:
1328 flush_work(&gadget->work);
1329 device_del(&udc->dev);
1330
1331 err_unlist_udc:
1332 mutex_lock(&udc_lock);
1333 list_del(&udc->list);
1334 mutex_unlock(&udc_lock);
1335
1336 err_put_udc:
1337 put_device(&udc->dev);
1338
1339 error:
1340 return ret;
1341}
1342EXPORT_SYMBOL_GPL(usb_add_gadget);
1343
1344/**
1345 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1346 * @parent: the parent device to this udc. Usually the controller driver's
1347 * device.
1348 * @gadget: the gadget to be added to the list.
1349 * @release: a gadget release function.
1350 *
1351 * Returns zero on success, negative errno otherwise.
1352 * Calls the gadget release function in the latter case.
1353 */
1354int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1355 void (*release)(struct device *dev))
1356{
1357 int ret;
1358
1359 usb_initialize_gadget(parent, gadget, release);
1360 ret = usb_add_gadget(gadget);
1361 if (ret)
1362 usb_put_gadget(gadget);
1363 return ret;
1364}
1365EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1366
1367/**
1368 * usb_get_gadget_udc_name - get the name of the first UDC controller
1369 * This functions returns the name of the first UDC controller in the system.
1370 * Please note that this interface is usefull only for legacy drivers which
1371 * assume that there is only one UDC controller in the system and they need to
1372 * get its name before initialization. There is no guarantee that the UDC
1373 * of the returned name will be still available, when gadget driver registers
1374 * itself.
1375 *
1376 * Returns pointer to string with UDC controller name on success, NULL
1377 * otherwise. Caller should kfree() returned string.
1378 */
1379char *usb_get_gadget_udc_name(void)
1380{
1381 struct usb_udc *udc;
1382 char *name = NULL;
1383
1384 /* For now we take the first available UDC */
1385 mutex_lock(&udc_lock);
1386 list_for_each_entry(udc, &udc_list, list) {
1387 if (!udc->driver) {
1388 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1389 break;
1390 }
1391 }
1392 mutex_unlock(&udc_lock);
1393 return name;
1394}
1395EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1396
1397/**
1398 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1399 * @parent: the parent device to this udc. Usually the controller
1400 * driver's device.
1401 * @gadget: the gadget to be added to the list
1402 *
1403 * Returns zero on success, negative errno otherwise.
1404 */
1405int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1406{
1407 return usb_add_gadget_udc_release(parent, gadget, NULL);
1408}
1409EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1410
1411/**
1412 * usb_del_gadget - deletes a gadget and unregisters its udc
1413 * @gadget: the gadget to be deleted.
1414 *
1415 * This will unbind @gadget, if it is bound.
1416 * It will not do a final usb_put_gadget().
1417 */
1418void usb_del_gadget(struct usb_gadget *gadget)
1419{
1420 struct usb_udc *udc = gadget->udc;
1421
1422 if (!udc)
1423 return;
1424
1425 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1426
1427 mutex_lock(&udc_lock);
1428 list_del(&udc->list);
1429 mutex_unlock(&udc_lock);
1430
1431 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1432 flush_work(&gadget->work);
1433 device_del(&gadget->dev);
1434 ida_free(&gadget_id_numbers, gadget->id_number);
1435 device_unregister(&udc->dev);
1436}
1437EXPORT_SYMBOL_GPL(usb_del_gadget);
1438
1439/**
1440 * usb_del_gadget_udc - unregisters a gadget
1441 * @gadget: the gadget to be unregistered.
1442 *
1443 * Calls usb_del_gadget() and does a final usb_put_gadget().
1444 */
1445void usb_del_gadget_udc(struct usb_gadget *gadget)
1446{
1447 usb_del_gadget(gadget);
1448 usb_put_gadget(gadget);
1449}
1450EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1451
1452/* ------------------------------------------------------------------------- */
1453
1454static int gadget_match_driver(struct device *dev, struct device_driver *drv)
1455{
1456 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1457 struct usb_udc *udc = gadget->udc;
1458 struct usb_gadget_driver *driver = container_of(drv,
1459 struct usb_gadget_driver, driver);
1460
1461 /* If the driver specifies a udc_name, it must match the UDC's name */
1462 if (driver->udc_name &&
1463 strcmp(driver->udc_name, dev_name(&udc->dev)) != 0)
1464 return 0;
1465
1466 /* If the driver is already bound to a gadget, it doesn't match */
1467 if (driver->is_bound)
1468 return 0;
1469
1470 /* Otherwise any gadget driver matches any UDC */
1471 return 1;
1472}
1473
1474static int gadget_bind_driver(struct device *dev)
1475{
1476 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1477 struct usb_udc *udc = gadget->udc;
1478 struct usb_gadget_driver *driver = container_of(dev->driver,
1479 struct usb_gadget_driver, driver);
1480 int ret = 0;
1481
1482 mutex_lock(&udc_lock);
1483 if (driver->is_bound) {
1484 mutex_unlock(&udc_lock);
1485 return -ENXIO; /* Driver binds to only one gadget */
1486 }
1487 driver->is_bound = true;
1488 udc->driver = driver;
1489 mutex_unlock(&udc_lock);
1490
1491 dev_dbg(&udc->dev, "binding gadget driver [%s]\n", driver->function);
1492
1493 usb_gadget_udc_set_speed(udc, driver->max_speed);
1494
1495 ret = driver->bind(udc->gadget, driver);
1496 if (ret)
1497 goto err_bind;
1498
1499 ret = usb_gadget_udc_start(udc);
1500 if (ret)
1501 goto err_start;
1502 usb_gadget_enable_async_callbacks(udc);
1503 usb_udc_connect_control(udc);
1504
1505 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1506 return 0;
1507
1508 err_start:
1509 driver->unbind(udc->gadget);
1510
1511 err_bind:
1512 if (ret != -EISNAM)
1513 dev_err(&udc->dev, "failed to start %s: %d\n",
1514 driver->function, ret);
1515
1516 mutex_lock(&udc_lock);
1517 udc->driver = NULL;
1518 driver->is_bound = false;
1519 mutex_unlock(&udc_lock);
1520
1521 return ret;
1522}
1523
1524static void gadget_unbind_driver(struct device *dev)
1525{
1526 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1527 struct usb_udc *udc = gadget->udc;
1528 struct usb_gadget_driver *driver = udc->driver;
1529
1530 dev_dbg(&udc->dev, "unbinding gadget driver [%s]\n", driver->function);
1531
1532 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1533
1534 usb_gadget_disconnect(gadget);
1535 usb_gadget_disable_async_callbacks(udc);
1536 if (gadget->irq)
1537 synchronize_irq(gadget->irq);
1538 udc->driver->unbind(gadget);
1539 usb_gadget_udc_stop(udc);
1540
1541 mutex_lock(&udc_lock);
1542 driver->is_bound = false;
1543 udc->driver = NULL;
1544 mutex_unlock(&udc_lock);
1545}
1546
1547/* ------------------------------------------------------------------------- */
1548
1549int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver,
1550 struct module *owner, const char *mod_name)
1551{
1552 int ret;
1553
1554 if (!driver || !driver->bind || !driver->setup)
1555 return -EINVAL;
1556
1557 driver->driver.bus = &gadget_bus_type;
1558 driver->driver.owner = owner;
1559 driver->driver.mod_name = mod_name;
1560 ret = driver_register(&driver->driver);
1561 if (ret) {
1562 pr_warn("%s: driver registration failed: %d\n",
1563 driver->function, ret);
1564 return ret;
1565 }
1566
1567 mutex_lock(&udc_lock);
1568 if (!driver->is_bound) {
1569 if (driver->match_existing_only) {
1570 pr_warn("%s: couldn't find an available UDC or it's busy\n",
1571 driver->function);
1572 ret = -EBUSY;
1573 } else {
1574 pr_info("%s: couldn't find an available UDC\n",
1575 driver->function);
1576 ret = 0;
1577 }
1578 }
1579 mutex_unlock(&udc_lock);
1580
1581 if (ret)
1582 driver_unregister(&driver->driver);
1583 return ret;
1584}
1585EXPORT_SYMBOL_GPL(usb_gadget_register_driver_owner);
1586
1587int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1588{
1589 if (!driver || !driver->unbind)
1590 return -EINVAL;
1591
1592 driver_unregister(&driver->driver);
1593 return 0;
1594}
1595EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1596
1597/* ------------------------------------------------------------------------- */
1598
1599static ssize_t srp_store(struct device *dev,
1600 struct device_attribute *attr, const char *buf, size_t n)
1601{
1602 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1603
1604 if (sysfs_streq(buf, "1"))
1605 usb_gadget_wakeup(udc->gadget);
1606
1607 return n;
1608}
1609static DEVICE_ATTR_WO(srp);
1610
1611static ssize_t soft_connect_store(struct device *dev,
1612 struct device_attribute *attr, const char *buf, size_t n)
1613{
1614 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1615 ssize_t ret;
1616
1617 device_lock(&udc->gadget->dev);
1618 if (!udc->driver) {
1619 dev_err(dev, "soft-connect without a gadget driver\n");
1620 ret = -EOPNOTSUPP;
1621 goto out;
1622 }
1623
1624 if (sysfs_streq(buf, "connect")) {
1625 usb_gadget_udc_start(udc);
1626 usb_gadget_connect(udc->gadget);
1627 } else if (sysfs_streq(buf, "disconnect")) {
1628 usb_gadget_disconnect(udc->gadget);
1629 usb_gadget_udc_stop(udc);
1630 } else {
1631 dev_err(dev, "unsupported command '%s'\n", buf);
1632 ret = -EINVAL;
1633 goto out;
1634 }
1635
1636 ret = n;
1637out:
1638 device_unlock(&udc->gadget->dev);
1639 return ret;
1640}
1641static DEVICE_ATTR_WO(soft_connect);
1642
1643static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1644 char *buf)
1645{
1646 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1647 struct usb_gadget *gadget = udc->gadget;
1648
1649 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1650}
1651static DEVICE_ATTR_RO(state);
1652
1653static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1654 char *buf)
1655{
1656 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1657 struct usb_gadget_driver *drv;
1658 int rc = 0;
1659
1660 mutex_lock(&udc_lock);
1661 drv = udc->driver;
1662 if (drv && drv->function)
1663 rc = scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1664 mutex_unlock(&udc_lock);
1665 return rc;
1666}
1667static DEVICE_ATTR_RO(function);
1668
1669#define USB_UDC_SPEED_ATTR(name, param) \
1670ssize_t name##_show(struct device *dev, \
1671 struct device_attribute *attr, char *buf) \
1672{ \
1673 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1674 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1675 usb_speed_string(udc->gadget->param)); \
1676} \
1677static DEVICE_ATTR_RO(name)
1678
1679static USB_UDC_SPEED_ATTR(current_speed, speed);
1680static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1681
1682#define USB_UDC_ATTR(name) \
1683ssize_t name##_show(struct device *dev, \
1684 struct device_attribute *attr, char *buf) \
1685{ \
1686 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1687 struct usb_gadget *gadget = udc->gadget; \
1688 \
1689 return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1690} \
1691static DEVICE_ATTR_RO(name)
1692
1693static USB_UDC_ATTR(is_otg);
1694static USB_UDC_ATTR(is_a_peripheral);
1695static USB_UDC_ATTR(b_hnp_enable);
1696static USB_UDC_ATTR(a_hnp_support);
1697static USB_UDC_ATTR(a_alt_hnp_support);
1698static USB_UDC_ATTR(is_selfpowered);
1699
1700static struct attribute *usb_udc_attrs[] = {
1701 &dev_attr_srp.attr,
1702 &dev_attr_soft_connect.attr,
1703 &dev_attr_state.attr,
1704 &dev_attr_function.attr,
1705 &dev_attr_current_speed.attr,
1706 &dev_attr_maximum_speed.attr,
1707
1708 &dev_attr_is_otg.attr,
1709 &dev_attr_is_a_peripheral.attr,
1710 &dev_attr_b_hnp_enable.attr,
1711 &dev_attr_a_hnp_support.attr,
1712 &dev_attr_a_alt_hnp_support.attr,
1713 &dev_attr_is_selfpowered.attr,
1714 NULL,
1715};
1716
1717static const struct attribute_group usb_udc_attr_group = {
1718 .attrs = usb_udc_attrs,
1719};
1720
1721static const struct attribute_group *usb_udc_attr_groups[] = {
1722 &usb_udc_attr_group,
1723 NULL,
1724};
1725
1726static int usb_udc_uevent(const struct device *dev, struct kobj_uevent_env *env)
1727{
1728 const struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1729 int ret;
1730
1731 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1732 if (ret) {
1733 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1734 return ret;
1735 }
1736
1737 mutex_lock(&udc_lock);
1738 if (udc->driver)
1739 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1740 udc->driver->function);
1741 mutex_unlock(&udc_lock);
1742 if (ret) {
1743 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1744 return ret;
1745 }
1746
1747 return 0;
1748}
1749
1750static struct bus_type gadget_bus_type = {
1751 .name = "gadget",
1752 .probe = gadget_bind_driver,
1753 .remove = gadget_unbind_driver,
1754 .match = gadget_match_driver,
1755};
1756
1757static int __init usb_udc_init(void)
1758{
1759 int rc;
1760
1761 udc_class = class_create(THIS_MODULE, "udc");
1762 if (IS_ERR(udc_class)) {
1763 pr_err("failed to create udc class --> %ld\n",
1764 PTR_ERR(udc_class));
1765 return PTR_ERR(udc_class);
1766 }
1767
1768 udc_class->dev_uevent = usb_udc_uevent;
1769
1770 rc = bus_register(&gadget_bus_type);
1771 if (rc)
1772 class_destroy(udc_class);
1773 return rc;
1774}
1775subsys_initcall(usb_udc_init);
1776
1777static void __exit usb_udc_exit(void)
1778{
1779 bus_unregister(&gadget_bus_type);
1780 class_destroy(udc_class);
1781}
1782module_exit(usb_udc_exit);
1783
1784MODULE_DESCRIPTION("UDC Framework");
1785MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1786MODULE_LICENSE("GPL v2");