1 // SPDX-License-Identifier: GPL-2.0
3 * udc.c - Core UDC Framework
5 * Copyright (C) 2010 Texas Instruments
6 * Author: Felipe Balbi <balbi@ti.com>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/device.h>
12 #include <linux/list.h>
13 #include <linux/err.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/sched/task_stack.h>
16 #include <linux/workqueue.h>
18 #include <linux/usb/ch9.h>
19 #include <linux/usb/gadget.h>
20 #include <linux/usb.h>
25 * struct usb_udc - describes one usb device controller
26 * @driver - the gadget driver pointer. For use by the class code
27 * @dev - the child device to the actual controller
28 * @gadget - the gadget. For use by the class code
29 * @list - for use by the udc class driver
30 * @vbus - for udcs who care about vbus status, this value is real vbus status;
31 * for udcs who do not care about vbus status, this value is always true
33 * This represents the internal data structure which is used by the UDC-class
34 * to hold information about udc driver and gadget together.
37 struct usb_gadget_driver *driver;
38 struct usb_gadget *gadget;
40 struct list_head list;
44 static struct class *udc_class;
45 static LIST_HEAD(udc_list);
46 static LIST_HEAD(gadget_driver_pending_list);
47 static DEFINE_MUTEX(udc_lock);
49 static int udc_bind_to_driver(struct usb_udc *udc,
50 struct usb_gadget_driver *driver);
52 /* ------------------------------------------------------------------------- */
55 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
56 * @ep:the endpoint being configured
57 * @maxpacket_limit:value of maximum packet size limit
59 * This function should be used only in UDC drivers to initialize endpoint
60 * (usually in probe function).
62 void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
63 unsigned maxpacket_limit)
65 ep->maxpacket_limit = maxpacket_limit;
66 ep->maxpacket = maxpacket_limit;
68 trace_usb_ep_set_maxpacket_limit(ep, 0);
70 EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
73 * usb_ep_enable - configure endpoint, making it usable
74 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
75 * drivers discover endpoints through the ep_list of a usb_gadget.
77 * When configurations are set, or when interface settings change, the driver
78 * will enable or disable the relevant endpoints. while it is enabled, an
79 * endpoint may be used for i/o until the driver receives a disconnect() from
80 * the host or until the endpoint is disabled.
82 * the ep0 implementation (which calls this routine) must ensure that the
83 * hardware capabilities of each endpoint match the descriptor provided
84 * for it. for example, an endpoint named "ep2in-bulk" would be usable
85 * for interrupt transfers as well as bulk, but it likely couldn't be used
86 * for iso transfers or for endpoint 14. some endpoints are fully
87 * configurable, with more generic names like "ep-a". (remember that for
88 * USB, "in" means "towards the USB master".)
90 * This routine must be called in process context.
92 * returns zero, or a negative error code.
94 int usb_ep_enable(struct usb_ep *ep)
101 ret = ep->ops->enable(ep, ep->desc);
108 trace_usb_ep_enable(ep, ret);
112 EXPORT_SYMBOL_GPL(usb_ep_enable);
115 * usb_ep_disable - endpoint is no longer usable
116 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
118 * no other task may be using this endpoint when this is called.
119 * any pending and uncompleted requests will complete with status
120 * indicating disconnect (-ESHUTDOWN) before this call returns.
121 * gadget drivers must call usb_ep_enable() again before queueing
122 * requests to the endpoint.
124 * This routine must be called in process context.
126 * returns zero, or a negative error code.
128 int usb_ep_disable(struct usb_ep *ep)
135 ret = ep->ops->disable(ep);
142 trace_usb_ep_disable(ep, ret);
146 EXPORT_SYMBOL_GPL(usb_ep_disable);
149 * usb_ep_alloc_request - allocate a request object to use with this endpoint
150 * @ep:the endpoint to be used with with the request
151 * @gfp_flags:GFP_* flags to use
153 * Request objects must be allocated with this call, since they normally
154 * need controller-specific setup and may even need endpoint-specific
155 * resources such as allocation of DMA descriptors.
156 * Requests may be submitted with usb_ep_queue(), and receive a single
157 * completion callback. Free requests with usb_ep_free_request(), when
158 * they are no longer needed.
160 * Returns the request, or null if one could not be allocated.
162 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
165 struct usb_request *req = NULL;
167 req = ep->ops->alloc_request(ep, gfp_flags);
169 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
173 EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
176 * usb_ep_free_request - frees a request object
177 * @ep:the endpoint associated with the request
178 * @req:the request being freed
180 * Reverses the effect of usb_ep_alloc_request().
181 * Caller guarantees the request is not queued, and that it will
182 * no longer be requeued (or otherwise used).
184 void usb_ep_free_request(struct usb_ep *ep,
185 struct usb_request *req)
187 trace_usb_ep_free_request(ep, req, 0);
188 ep->ops->free_request(ep, req);
190 EXPORT_SYMBOL_GPL(usb_ep_free_request);
193 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
194 * @ep:the endpoint associated with the request
195 * @req:the request being submitted
196 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
197 * pre-allocate all necessary memory with the request.
199 * This tells the device controller to perform the specified request through
200 * that endpoint (reading or writing a buffer). When the request completes,
201 * including being canceled by usb_ep_dequeue(), the request's completion
202 * routine is called to return the request to the driver. Any endpoint
203 * (except control endpoints like ep0) may have more than one transfer
204 * request queued; they complete in FIFO order. Once a gadget driver
205 * submits a request, that request may not be examined or modified until it
206 * is given back to that driver through the completion callback.
208 * Each request is turned into one or more packets. The controller driver
209 * never merges adjacent requests into the same packet. OUT transfers
210 * will sometimes use data that's already buffered in the hardware.
211 * Drivers can rely on the fact that the first byte of the request's buffer
212 * always corresponds to the first byte of some USB packet, for both
213 * IN and OUT transfers.
215 * Bulk endpoints can queue any amount of data; the transfer is packetized
216 * automatically. The last packet will be short if the request doesn't fill it
217 * out completely. Zero length packets (ZLPs) should be avoided in portable
218 * protocols since not all usb hardware can successfully handle zero length
219 * packets. (ZLPs may be explicitly written, and may be implicitly written if
220 * the request 'zero' flag is set.) Bulk endpoints may also be used
221 * for interrupt transfers; but the reverse is not true, and some endpoints
222 * won't support every interrupt transfer. (Such as 768 byte packets.)
224 * Interrupt-only endpoints are less functional than bulk endpoints, for
225 * example by not supporting queueing or not handling buffers that are
226 * larger than the endpoint's maxpacket size. They may also treat data
227 * toggle differently.
229 * Control endpoints ... after getting a setup() callback, the driver queues
230 * one response (even if it would be zero length). That enables the
231 * status ack, after transferring data as specified in the response. Setup
232 * functions may return negative error codes to generate protocol stalls.
233 * (Note that some USB device controllers disallow protocol stall responses
234 * in some cases.) When control responses are deferred (the response is
235 * written after the setup callback returns), then usb_ep_set_halt() may be
236 * used on ep0 to trigger protocol stalls. Depending on the controller,
237 * it may not be possible to trigger a status-stage protocol stall when the
238 * data stage is over, that is, from within the response's completion
241 * For periodic endpoints, like interrupt or isochronous ones, the usb host
242 * arranges to poll once per interval, and the gadget driver usually will
243 * have queued some data to transfer at that time.
245 * Note that @req's ->complete() callback must never be called from
246 * within usb_ep_queue() as that can create deadlock situations.
248 * This routine may be called in interrupt context.
250 * Returns zero, or a negative error code. Endpoints that are not enabled
251 * report errors; errors will also be
252 * reported when the usb peripheral is disconnected.
254 * If and only if @req is successfully queued (the return value is zero),
255 * @req->complete() will be called exactly once, when the Gadget core and
256 * UDC are finished with the request. When the completion function is called,
257 * control of the request is returned to the device driver which submitted it.
258 * The completion handler may then immediately free or reuse @req.
260 int usb_ep_queue(struct usb_ep *ep,
261 struct usb_request *req, gfp_t gfp_flags)
265 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
270 ret = ep->ops->queue(ep, req, gfp_flags);
273 trace_usb_ep_queue(ep, req, ret);
277 EXPORT_SYMBOL_GPL(usb_ep_queue);
280 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
281 * @ep:the endpoint associated with the request
282 * @req:the request being canceled
284 * If the request is still active on the endpoint, it is dequeued and its
285 * completion routine is called (with status -ECONNRESET); else a negative
286 * error code is returned. This is guaranteed to happen before the call to
287 * usb_ep_dequeue() returns.
289 * Note that some hardware can't clear out write fifos (to unlink the request
290 * at the head of the queue) except as part of disconnecting from usb. Such
291 * restrictions prevent drivers from supporting configuration changes,
292 * even to configuration zero (a "chapter 9" requirement).
294 * This routine may be called in interrupt context.
296 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
300 ret = ep->ops->dequeue(ep, req);
301 trace_usb_ep_dequeue(ep, req, ret);
305 EXPORT_SYMBOL_GPL(usb_ep_dequeue);
308 * usb_ep_set_halt - sets the endpoint halt feature.
309 * @ep: the non-isochronous endpoint being stalled
311 * Use this to stall an endpoint, perhaps as an error report.
312 * Except for control endpoints,
313 * the endpoint stays halted (will not stream any data) until the host
314 * clears this feature; drivers may need to empty the endpoint's request
315 * queue first, to make sure no inappropriate transfers happen.
317 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
318 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
319 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
320 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
322 * This routine may be called in interrupt context.
324 * Returns zero, or a negative error code. On success, this call sets
325 * underlying hardware state that blocks data transfers.
326 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
327 * transfer requests are still queued, or if the controller hardware
328 * (usually a FIFO) still holds bytes that the host hasn't collected.
330 int usb_ep_set_halt(struct usb_ep *ep)
334 ret = ep->ops->set_halt(ep, 1);
335 trace_usb_ep_set_halt(ep, ret);
339 EXPORT_SYMBOL_GPL(usb_ep_set_halt);
342 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
343 * @ep:the bulk or interrupt endpoint being reset
345 * Use this when responding to the standard usb "set interface" request,
346 * for endpoints that aren't reconfigured, after clearing any other state
347 * in the endpoint's i/o queue.
349 * This routine may be called in interrupt context.
351 * Returns zero, or a negative error code. On success, this call clears
352 * the underlying hardware state reflecting endpoint halt and data toggle.
353 * Note that some hardware can't support this request (like pxa2xx_udc),
354 * and accordingly can't correctly implement interface altsettings.
356 int usb_ep_clear_halt(struct usb_ep *ep)
360 ret = ep->ops->set_halt(ep, 0);
361 trace_usb_ep_clear_halt(ep, ret);
365 EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
368 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
369 * @ep: the endpoint being wedged
371 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
372 * requests. If the gadget driver clears the halt status, it will
373 * automatically unwedge the endpoint.
375 * This routine may be called in interrupt context.
377 * Returns zero on success, else negative errno.
379 int usb_ep_set_wedge(struct usb_ep *ep)
383 if (ep->ops->set_wedge)
384 ret = ep->ops->set_wedge(ep);
386 ret = ep->ops->set_halt(ep, 1);
388 trace_usb_ep_set_wedge(ep, ret);
392 EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
395 * usb_ep_fifo_status - returns number of bytes in fifo, or error
396 * @ep: the endpoint whose fifo status is being checked.
398 * FIFO endpoints may have "unclaimed data" in them in certain cases,
399 * such as after aborted transfers. Hosts may not have collected all
400 * the IN data written by the gadget driver (and reported by a request
401 * completion). The gadget driver may not have collected all the data
402 * written OUT to it by the host. Drivers that need precise handling for
403 * fault reporting or recovery may need to use this call.
405 * This routine may be called in interrupt context.
407 * This returns the number of such bytes in the fifo, or a negative
408 * errno if the endpoint doesn't use a FIFO or doesn't support such
411 int usb_ep_fifo_status(struct usb_ep *ep)
415 if (ep->ops->fifo_status)
416 ret = ep->ops->fifo_status(ep);
420 trace_usb_ep_fifo_status(ep, ret);
424 EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
427 * usb_ep_fifo_flush - flushes contents of a fifo
428 * @ep: the endpoint whose fifo is being flushed.
430 * This call may be used to flush the "unclaimed data" that may exist in
431 * an endpoint fifo after abnormal transaction terminations. The call
432 * must never be used except when endpoint is not being used for any
433 * protocol translation.
435 * This routine may be called in interrupt context.
437 void usb_ep_fifo_flush(struct usb_ep *ep)
439 if (ep->ops->fifo_flush)
440 ep->ops->fifo_flush(ep);
442 trace_usb_ep_fifo_flush(ep, 0);
444 EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
446 /* ------------------------------------------------------------------------- */
449 * usb_gadget_frame_number - returns the current frame number
450 * @gadget: controller that reports the frame number
452 * Returns the usb frame number, normally eleven bits from a SOF packet,
453 * or negative errno if this device doesn't support this capability.
455 int usb_gadget_frame_number(struct usb_gadget *gadget)
459 ret = gadget->ops->get_frame(gadget);
461 trace_usb_gadget_frame_number(gadget, ret);
465 EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
468 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
469 * @gadget: controller used to wake up the host
471 * Returns zero on success, else negative error code if the hardware
472 * doesn't support such attempts, or its support has not been enabled
473 * by the usb host. Drivers must return device descriptors that report
474 * their ability to support this, or hosts won't enable it.
476 * This may also try to use SRP to wake the host and start enumeration,
477 * even if OTG isn't otherwise in use. OTG devices may also start
478 * remote wakeup even when hosts don't explicitly enable it.
480 int usb_gadget_wakeup(struct usb_gadget *gadget)
484 if (!gadget->ops->wakeup) {
489 ret = gadget->ops->wakeup(gadget);
492 trace_usb_gadget_wakeup(gadget, ret);
496 EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
499 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
500 * @gadget:the device being declared as self-powered
502 * this affects the device status reported by the hardware driver
503 * to reflect that it now has a local power supply.
505 * returns zero on success, else negative errno.
507 int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
511 if (!gadget->ops->set_selfpowered) {
516 ret = gadget->ops->set_selfpowered(gadget, 1);
519 trace_usb_gadget_set_selfpowered(gadget, ret);
523 EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
526 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
527 * @gadget:the device being declared as bus-powered
529 * this affects the device status reported by the hardware driver.
530 * some hardware may not support bus-powered operation, in which
531 * case this feature's value can never change.
533 * returns zero on success, else negative errno.
535 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
539 if (!gadget->ops->set_selfpowered) {
544 ret = gadget->ops->set_selfpowered(gadget, 0);
547 trace_usb_gadget_clear_selfpowered(gadget, ret);
551 EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
554 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
555 * @gadget:The device which now has VBUS power.
558 * This call is used by a driver for an external transceiver (or GPIO)
559 * that detects a VBUS power session starting. Common responses include
560 * resuming the controller, activating the D+ (or D-) pullup to let the
561 * host detect that a USB device is attached, and starting to draw power
562 * (8mA or possibly more, especially after SET_CONFIGURATION).
564 * Returns zero on success, else negative errno.
566 int usb_gadget_vbus_connect(struct usb_gadget *gadget)
570 if (!gadget->ops->vbus_session) {
575 ret = gadget->ops->vbus_session(gadget, 1);
578 trace_usb_gadget_vbus_connect(gadget, ret);
582 EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
585 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
586 * @gadget:The device whose VBUS usage is being described
587 * @mA:How much current to draw, in milliAmperes. This should be twice
588 * the value listed in the configuration descriptor bMaxPower field.
590 * This call is used by gadget drivers during SET_CONFIGURATION calls,
591 * reporting how much power the device may consume. For example, this
592 * could affect how quickly batteries are recharged.
594 * Returns zero on success, else negative errno.
596 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
600 if (!gadget->ops->vbus_draw) {
605 ret = gadget->ops->vbus_draw(gadget, mA);
610 trace_usb_gadget_vbus_draw(gadget, ret);
614 EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
617 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
618 * @gadget:the device whose VBUS supply is being described
621 * This call is used by a driver for an external transceiver (or GPIO)
622 * that detects a VBUS power session ending. Common responses include
623 * reversing everything done in usb_gadget_vbus_connect().
625 * Returns zero on success, else negative errno.
627 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
631 if (!gadget->ops->vbus_session) {
636 ret = gadget->ops->vbus_session(gadget, 0);
639 trace_usb_gadget_vbus_disconnect(gadget, ret);
643 EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
646 * usb_gadget_connect - software-controlled connect to USB host
647 * @gadget:the peripheral being connected
649 * Enables the D+ (or potentially D-) pullup. The host will start
650 * enumerating this gadget when the pullup is active and a VBUS session
651 * is active (the link is powered). This pullup is always enabled unless
652 * usb_gadget_disconnect() has been used to disable it.
654 * Returns zero on success, else negative errno.
656 int usb_gadget_connect(struct usb_gadget *gadget)
660 if (!gadget->ops->pullup) {
665 if (gadget->deactivated) {
667 * If gadget is deactivated we only save new state.
668 * Gadget will be connected automatically after activation.
670 gadget->connected = true;
674 ret = gadget->ops->pullup(gadget, 1);
676 gadget->connected = 1;
679 trace_usb_gadget_connect(gadget, ret);
683 EXPORT_SYMBOL_GPL(usb_gadget_connect);
686 * usb_gadget_disconnect - software-controlled disconnect from USB host
687 * @gadget:the peripheral being disconnected
689 * Disables the D+ (or potentially D-) pullup, which the host may see
690 * as a disconnect (when a VBUS session is active). Not all systems
691 * support software pullup controls.
693 * Returns zero on success, else negative errno.
695 int usb_gadget_disconnect(struct usb_gadget *gadget)
699 if (!gadget->ops->pullup) {
704 if (gadget->deactivated) {
706 * If gadget is deactivated we only save new state.
707 * Gadget will stay disconnected after activation.
709 gadget->connected = false;
713 ret = gadget->ops->pullup(gadget, 0);
715 gadget->connected = 0;
718 trace_usb_gadget_disconnect(gadget, ret);
722 EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
725 * usb_gadget_deactivate - deactivate function which is not ready to work
726 * @gadget: the peripheral being deactivated
728 * This routine may be used during the gadget driver bind() call to prevent
729 * the peripheral from ever being visible to the USB host, unless later
730 * usb_gadget_activate() is called. For example, user mode components may
731 * need to be activated before the system can talk to hosts.
733 * Returns zero on success, else negative errno.
735 int usb_gadget_deactivate(struct usb_gadget *gadget)
739 if (gadget->deactivated)
742 if (gadget->connected) {
743 ret = usb_gadget_disconnect(gadget);
748 * If gadget was being connected before deactivation, we want
749 * to reconnect it in usb_gadget_activate().
751 gadget->connected = true;
753 gadget->deactivated = true;
756 trace_usb_gadget_deactivate(gadget, ret);
760 EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
763 * usb_gadget_activate - activate function which is not ready to work
764 * @gadget: the peripheral being activated
766 * This routine activates gadget which was previously deactivated with
767 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
769 * Returns zero on success, else negative errno.
771 int usb_gadget_activate(struct usb_gadget *gadget)
775 if (!gadget->deactivated)
778 gadget->deactivated = false;
781 * If gadget has been connected before deactivation, or became connected
782 * while it was being deactivated, we call usb_gadget_connect().
784 if (gadget->connected)
785 ret = usb_gadget_connect(gadget);
788 trace_usb_gadget_activate(gadget, ret);
792 EXPORT_SYMBOL_GPL(usb_gadget_activate);
794 /* ------------------------------------------------------------------------- */
796 #ifdef CONFIG_HAS_DMA
798 int usb_gadget_map_request_by_dev(struct device *dev,
799 struct usb_request *req, int is_in)
801 if (req->length == 0)
807 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
808 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
810 dev_err(dev, "failed to map SGs\n");
814 req->num_mapped_sgs = mapped;
816 if (is_vmalloc_addr(req->buf)) {
817 dev_err(dev, "buffer is not dma capable\n");
819 } else if (object_is_on_stack(req->buf)) {
820 dev_err(dev, "buffer is on stack\n");
824 req->dma = dma_map_single(dev, req->buf, req->length,
825 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
827 if (dma_mapping_error(dev, req->dma)) {
828 dev_err(dev, "failed to map buffer\n");
837 EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
839 int usb_gadget_map_request(struct usb_gadget *gadget,
840 struct usb_request *req, int is_in)
842 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
844 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
846 void usb_gadget_unmap_request_by_dev(struct device *dev,
847 struct usb_request *req, int is_in)
849 if (req->length == 0)
852 if (req->num_mapped_sgs) {
853 dma_unmap_sg(dev, req->sg, req->num_sgs,
854 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
856 req->num_mapped_sgs = 0;
857 } else if (req->dma_mapped) {
858 dma_unmap_single(dev, req->dma, req->length,
859 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
863 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
865 void usb_gadget_unmap_request(struct usb_gadget *gadget,
866 struct usb_request *req, int is_in)
868 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
870 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
872 #endif /* CONFIG_HAS_DMA */
874 /* ------------------------------------------------------------------------- */
877 * usb_gadget_giveback_request - give the request back to the gadget layer
878 * Context: in_interrupt()
880 * This is called by device controller drivers in order to return the
881 * completed request back to the gadget layer.
883 void usb_gadget_giveback_request(struct usb_ep *ep,
884 struct usb_request *req)
886 if (likely(req->status == 0))
887 usb_led_activity(USB_LED_EVENT_GADGET);
889 trace_usb_gadget_giveback_request(ep, req, 0);
891 req->complete(ep, req);
893 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
895 /* ------------------------------------------------------------------------- */
898 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
899 * in second parameter or NULL if searched endpoint not found
900 * @g: controller to check for quirk
901 * @name: name of searched endpoint
903 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
907 gadget_for_each_ep(ep, g) {
908 if (!strcmp(ep->name, name))
914 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
916 /* ------------------------------------------------------------------------- */
918 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
919 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
920 struct usb_ss_ep_comp_descriptor *ep_comp)
924 int num_req_streams = 0;
926 /* endpoint already claimed? */
930 type = usb_endpoint_type(desc);
931 max = usb_endpoint_maxp(desc);
933 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
935 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
938 if (max > ep->maxpacket_limit)
941 /* "high bandwidth" works only at high speed */
942 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
946 case USB_ENDPOINT_XFER_CONTROL:
947 /* only support ep0 for portable CONTROL traffic */
949 case USB_ENDPOINT_XFER_ISOC:
950 if (!ep->caps.type_iso)
952 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
953 if (!gadget_is_dualspeed(gadget) && max > 1023)
956 case USB_ENDPOINT_XFER_BULK:
957 if (!ep->caps.type_bulk)
959 if (ep_comp && gadget_is_superspeed(gadget)) {
960 /* Get the number of required streams from the
961 * EP companion descriptor and see if the EP
964 num_req_streams = ep_comp->bmAttributes & 0x1f;
965 if (num_req_streams > ep->max_streams)
969 case USB_ENDPOINT_XFER_INT:
970 /* Bulk endpoints handle interrupt transfers,
971 * except the toggle-quirky iso-synch kind
973 if (!ep->caps.type_int && !ep->caps.type_bulk)
975 /* INT: limit 64 bytes full speed, 1024 high/super speed */
976 if (!gadget_is_dualspeed(gadget) && max > 64)
983 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
985 /* ------------------------------------------------------------------------- */
987 static void usb_gadget_state_work(struct work_struct *work)
989 struct usb_gadget *gadget = work_to_gadget(work);
990 struct usb_udc *udc = gadget->udc;
993 sysfs_notify(&udc->dev.kobj, NULL, "state");
996 void usb_gadget_set_state(struct usb_gadget *gadget,
997 enum usb_device_state state)
999 gadget->state = state;
1000 schedule_work(&gadget->work);
1002 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
1004 /* ------------------------------------------------------------------------- */
1006 static void usb_udc_connect_control(struct usb_udc *udc)
1009 usb_gadget_connect(udc->gadget);
1011 usb_gadget_disconnect(udc->gadget);
1015 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1016 * connect or disconnect gadget
1017 * @gadget: The gadget which vbus change occurs
1018 * @status: The vbus status
1020 * The udc driver calls it when it wants to connect or disconnect gadget
1021 * according to vbus status.
1023 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1025 struct usb_udc *udc = gadget->udc;
1029 usb_udc_connect_control(udc);
1032 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1035 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1036 * @gadget: The gadget which bus reset occurs
1037 * @driver: The gadget driver we want to notify
1039 * If the udc driver has bus reset handler, it needs to call this when the bus
1040 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1041 * well as updates gadget state.
1043 void usb_gadget_udc_reset(struct usb_gadget *gadget,
1044 struct usb_gadget_driver *driver)
1046 driver->reset(gadget);
1047 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1049 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1052 * usb_gadget_udc_start - tells usb device controller to start up
1053 * @udc: The UDC to be started
1055 * This call is issued by the UDC Class driver when it's about
1056 * to register a gadget driver to the device controller, before
1057 * calling gadget driver's bind() method.
1059 * It allows the controller to be powered off until strictly
1060 * necessary to have it powered on.
1062 * Returns zero on success, else negative errno.
1064 static inline int usb_gadget_udc_start(struct usb_udc *udc)
1066 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1070 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
1071 * @gadget: The device we want to stop activity
1072 * @driver: The driver to unbind from @gadget
1074 * This call is issued by the UDC Class driver after calling
1075 * gadget driver's unbind() method.
1077 * The details are implementation specific, but it can go as
1078 * far as powering off UDC completely and disable its data
1081 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
1083 udc->gadget->ops->udc_stop(udc->gadget);
1087 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1089 * @udc: The device we want to set maximum speed
1090 * @speed: The maximum speed to allowed to run
1092 * This call is issued by the UDC Class driver before calling
1093 * usb_gadget_udc_start() in order to make sure that we don't try to
1094 * connect on speeds the gadget driver doesn't support.
1096 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1097 enum usb_device_speed speed)
1099 if (udc->gadget->ops->udc_set_speed) {
1100 enum usb_device_speed s;
1102 s = min(speed, udc->gadget->max_speed);
1103 udc->gadget->ops->udc_set_speed(udc->gadget, s);
1108 * usb_udc_release - release the usb_udc struct
1109 * @dev: the dev member within usb_udc
1111 * This is called by driver's core in order to free memory once the last
1112 * reference is released.
1114 static void usb_udc_release(struct device *dev)
1116 struct usb_udc *udc;
1118 udc = container_of(dev, struct usb_udc, dev);
1119 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1123 static const struct attribute_group *usb_udc_attr_groups[];
1125 static void usb_udc_nop_release(struct device *dev)
1127 dev_vdbg(dev, "%s\n", __func__);
1130 /* should be called with udc_lock held */
1131 static int check_pending_gadget_drivers(struct usb_udc *udc)
1133 struct usb_gadget_driver *driver;
1136 list_for_each_entry(driver, &gadget_driver_pending_list, pending)
1137 if (!driver->udc_name || strcmp(driver->udc_name,
1138 dev_name(&udc->dev)) == 0) {
1139 ret = udc_bind_to_driver(udc, driver);
1140 if (ret != -EPROBE_DEFER)
1141 list_del(&driver->pending);
1149 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1150 * @parent: the parent device to this udc. Usually the controller driver's
1152 * @gadget: the gadget to be added to the list.
1153 * @release: a gadget release function.
1155 * Returns zero on success, negative errno otherwise.
1156 * Calls the gadget release function in the latter case.
1158 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1159 void (*release)(struct device *dev))
1161 struct usb_udc *udc;
1164 dev_set_name(&gadget->dev, "gadget");
1165 INIT_WORK(&gadget->work, usb_gadget_state_work);
1166 gadget->dev.parent = parent;
1169 gadget->dev.release = release;
1171 gadget->dev.release = usb_udc_nop_release;
1173 device_initialize(&gadget->dev);
1175 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1177 goto err_put_gadget;
1179 device_initialize(&udc->dev);
1180 udc->dev.release = usb_udc_release;
1181 udc->dev.class = udc_class;
1182 udc->dev.groups = usb_udc_attr_groups;
1183 udc->dev.parent = parent;
1184 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
1188 ret = device_add(&gadget->dev);
1192 udc->gadget = gadget;
1195 mutex_lock(&udc_lock);
1196 list_add_tail(&udc->list, &udc_list);
1198 ret = device_add(&udc->dev);
1200 goto err_unlist_udc;
1202 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1205 /* pick up one of pending gadget drivers */
1206 ret = check_pending_gadget_drivers(udc);
1210 mutex_unlock(&udc_lock);
1215 device_del(&udc->dev);
1218 list_del(&udc->list);
1219 mutex_unlock(&udc_lock);
1221 device_del(&gadget->dev);
1224 put_device(&udc->dev);
1227 put_device(&gadget->dev);
1230 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1233 * usb_get_gadget_udc_name - get the name of the first UDC controller
1234 * This functions returns the name of the first UDC controller in the system.
1235 * Please note that this interface is usefull only for legacy drivers which
1236 * assume that there is only one UDC controller in the system and they need to
1237 * get its name before initialization. There is no guarantee that the UDC
1238 * of the returned name will be still available, when gadget driver registers
1241 * Returns pointer to string with UDC controller name on success, NULL
1242 * otherwise. Caller should kfree() returned string.
1244 char *usb_get_gadget_udc_name(void)
1246 struct usb_udc *udc;
1249 /* For now we take the first available UDC */
1250 mutex_lock(&udc_lock);
1251 list_for_each_entry(udc, &udc_list, list) {
1253 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1257 mutex_unlock(&udc_lock);
1260 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1263 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1264 * @parent: the parent device to this udc. Usually the controller
1266 * @gadget: the gadget to be added to the list
1268 * Returns zero on success, negative errno otherwise.
1270 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1272 return usb_add_gadget_udc_release(parent, gadget, NULL);
1274 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1276 static void usb_gadget_remove_driver(struct usb_udc *udc)
1278 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
1279 udc->driver->function);
1281 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1283 usb_gadget_disconnect(udc->gadget);
1284 udc->driver->disconnect(udc->gadget);
1285 udc->driver->unbind(udc->gadget);
1286 usb_gadget_udc_stop(udc);
1289 udc->dev.driver = NULL;
1290 udc->gadget->dev.driver = NULL;
1294 * usb_del_gadget_udc - deletes @udc from udc_list
1295 * @gadget: the gadget to be removed.
1297 * This, will call usb_gadget_unregister_driver() if
1298 * the @udc is still busy.
1300 void usb_del_gadget_udc(struct usb_gadget *gadget)
1302 struct usb_udc *udc = gadget->udc;
1307 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1309 mutex_lock(&udc_lock);
1310 list_del(&udc->list);
1313 struct usb_gadget_driver *driver = udc->driver;
1315 usb_gadget_remove_driver(udc);
1316 list_add(&driver->pending, &gadget_driver_pending_list);
1318 mutex_unlock(&udc_lock);
1320 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1321 flush_work(&gadget->work);
1322 device_unregister(&udc->dev);
1323 device_unregister(&gadget->dev);
1324 memset(&gadget->dev, 0x00, sizeof(gadget->dev));
1326 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1328 /* ------------------------------------------------------------------------- */
1330 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
1334 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
1337 udc->driver = driver;
1338 udc->dev.driver = &driver->driver;
1339 udc->gadget->dev.driver = &driver->driver;
1341 usb_gadget_udc_set_speed(udc, driver->max_speed);
1343 ret = driver->bind(udc->gadget, driver);
1346 ret = usb_gadget_udc_start(udc);
1348 driver->unbind(udc->gadget);
1351 usb_udc_connect_control(udc);
1353 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1357 dev_err(&udc->dev, "failed to start %s: %d\n",
1358 udc->driver->function, ret);
1360 udc->dev.driver = NULL;
1361 udc->gadget->dev.driver = NULL;
1365 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
1367 struct usb_udc *udc = NULL;
1370 if (!driver || !driver->bind || !driver->setup)
1373 mutex_lock(&udc_lock);
1374 if (driver->udc_name) {
1375 list_for_each_entry(udc, &udc_list, list) {
1376 ret = strcmp(driver->udc_name, dev_name(&udc->dev));
1382 else if (udc->driver)
1387 list_for_each_entry(udc, &udc_list, list) {
1388 /* For now we take the first one */
1394 if (!driver->match_existing_only) {
1395 list_add_tail(&driver->pending, &gadget_driver_pending_list);
1396 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
1401 mutex_unlock(&udc_lock);
1404 ret = udc_bind_to_driver(udc, driver);
1405 mutex_unlock(&udc_lock);
1408 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
1410 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1412 struct usb_udc *udc = NULL;
1415 if (!driver || !driver->unbind)
1418 mutex_lock(&udc_lock);
1419 list_for_each_entry(udc, &udc_list, list) {
1420 if (udc->driver == driver) {
1421 usb_gadget_remove_driver(udc);
1422 usb_gadget_set_state(udc->gadget,
1423 USB_STATE_NOTATTACHED);
1425 /* Maybe there is someone waiting for this UDC? */
1426 check_pending_gadget_drivers(udc);
1428 * For now we ignore bind errors as probably it's
1429 * not a valid reason to fail other's gadget unbind
1437 list_del(&driver->pending);
1440 mutex_unlock(&udc_lock);
1443 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1445 /* ------------------------------------------------------------------------- */
1447 static ssize_t srp_store(struct device *dev,
1448 struct device_attribute *attr, const char *buf, size_t n)
1450 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1452 if (sysfs_streq(buf, "1"))
1453 usb_gadget_wakeup(udc->gadget);
1457 static DEVICE_ATTR_WO(srp);
1459 static ssize_t soft_connect_store(struct device *dev,
1460 struct device_attribute *attr, const char *buf, size_t n)
1462 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1465 dev_err(dev, "soft-connect without a gadget driver\n");
1469 if (sysfs_streq(buf, "connect")) {
1470 usb_gadget_udc_start(udc);
1471 usb_gadget_connect(udc->gadget);
1472 } else if (sysfs_streq(buf, "disconnect")) {
1473 usb_gadget_disconnect(udc->gadget);
1474 udc->driver->disconnect(udc->gadget);
1475 usb_gadget_udc_stop(udc);
1477 dev_err(dev, "unsupported command '%s'\n", buf);
1483 static DEVICE_ATTR_WO(soft_connect);
1485 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1488 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1489 struct usb_gadget *gadget = udc->gadget;
1491 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1493 static DEVICE_ATTR_RO(state);
1495 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1498 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1499 struct usb_gadget_driver *drv = udc->driver;
1501 if (!drv || !drv->function)
1503 return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1505 static DEVICE_ATTR_RO(function);
1507 #define USB_UDC_SPEED_ATTR(name, param) \
1508 ssize_t name##_show(struct device *dev, \
1509 struct device_attribute *attr, char *buf) \
1511 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1512 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1513 usb_speed_string(udc->gadget->param)); \
1515 static DEVICE_ATTR_RO(name)
1517 static USB_UDC_SPEED_ATTR(current_speed, speed);
1518 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1520 #define USB_UDC_ATTR(name) \
1521 ssize_t name##_show(struct device *dev, \
1522 struct device_attribute *attr, char *buf) \
1524 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1525 struct usb_gadget *gadget = udc->gadget; \
1527 return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1529 static DEVICE_ATTR_RO(name)
1531 static USB_UDC_ATTR(is_otg);
1532 static USB_UDC_ATTR(is_a_peripheral);
1533 static USB_UDC_ATTR(b_hnp_enable);
1534 static USB_UDC_ATTR(a_hnp_support);
1535 static USB_UDC_ATTR(a_alt_hnp_support);
1536 static USB_UDC_ATTR(is_selfpowered);
1538 static struct attribute *usb_udc_attrs[] = {
1540 &dev_attr_soft_connect.attr,
1541 &dev_attr_state.attr,
1542 &dev_attr_function.attr,
1543 &dev_attr_current_speed.attr,
1544 &dev_attr_maximum_speed.attr,
1546 &dev_attr_is_otg.attr,
1547 &dev_attr_is_a_peripheral.attr,
1548 &dev_attr_b_hnp_enable.attr,
1549 &dev_attr_a_hnp_support.attr,
1550 &dev_attr_a_alt_hnp_support.attr,
1551 &dev_attr_is_selfpowered.attr,
1555 static const struct attribute_group usb_udc_attr_group = {
1556 .attrs = usb_udc_attrs,
1559 static const struct attribute_group *usb_udc_attr_groups[] = {
1560 &usb_udc_attr_group,
1564 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
1566 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1569 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1571 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1576 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1577 udc->driver->function);
1579 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1587 static int __init usb_udc_init(void)
1589 udc_class = class_create(THIS_MODULE, "udc");
1590 if (IS_ERR(udc_class)) {
1591 pr_err("failed to create udc class --> %ld\n",
1592 PTR_ERR(udc_class));
1593 return PTR_ERR(udc_class);
1596 udc_class->dev_uevent = usb_udc_uevent;
1599 subsys_initcall(usb_udc_init);
1601 static void __exit usb_udc_exit(void)
1603 class_destroy(udc_class);
1605 module_exit(usb_udc_exit);
1607 MODULE_DESCRIPTION("UDC Framework");
1608 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1609 MODULE_LICENSE("GPL v2");