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 /* UDC drivers can't handle endpoints with maxpacket size 0 */
102 if (usb_endpoint_maxp(ep->desc) == 0) {
104 * We should log an error message here, but we can't call
105 * dev_err() because there's no way to find the gadget
112 ret = ep->ops->enable(ep, ep->desc);
119 trace_usb_ep_enable(ep, ret);
123 EXPORT_SYMBOL_GPL(usb_ep_enable);
126 * usb_ep_disable - endpoint is no longer usable
127 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
129 * no other task may be using this endpoint when this is called.
130 * any pending and uncompleted requests will complete with status
131 * indicating disconnect (-ESHUTDOWN) before this call returns.
132 * gadget drivers must call usb_ep_enable() again before queueing
133 * requests to the endpoint.
135 * This routine must be called in process context.
137 * returns zero, or a negative error code.
139 int usb_ep_disable(struct usb_ep *ep)
146 ret = ep->ops->disable(ep);
153 trace_usb_ep_disable(ep, ret);
157 EXPORT_SYMBOL_GPL(usb_ep_disable);
160 * usb_ep_alloc_request - allocate a request object to use with this endpoint
161 * @ep:the endpoint to be used with with the request
162 * @gfp_flags:GFP_* flags to use
164 * Request objects must be allocated with this call, since they normally
165 * need controller-specific setup and may even need endpoint-specific
166 * resources such as allocation of DMA descriptors.
167 * Requests may be submitted with usb_ep_queue(), and receive a single
168 * completion callback. Free requests with usb_ep_free_request(), when
169 * they are no longer needed.
171 * Returns the request, or null if one could not be allocated.
173 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
176 struct usb_request *req = NULL;
178 req = ep->ops->alloc_request(ep, gfp_flags);
180 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
184 EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
187 * usb_ep_free_request - frees a request object
188 * @ep:the endpoint associated with the request
189 * @req:the request being freed
191 * Reverses the effect of usb_ep_alloc_request().
192 * Caller guarantees the request is not queued, and that it will
193 * no longer be requeued (or otherwise used).
195 void usb_ep_free_request(struct usb_ep *ep,
196 struct usb_request *req)
198 trace_usb_ep_free_request(ep, req, 0);
199 ep->ops->free_request(ep, req);
201 EXPORT_SYMBOL_GPL(usb_ep_free_request);
204 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
205 * @ep:the endpoint associated with the request
206 * @req:the request being submitted
207 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
208 * pre-allocate all necessary memory with the request.
210 * This tells the device controller to perform the specified request through
211 * that endpoint (reading or writing a buffer). When the request completes,
212 * including being canceled by usb_ep_dequeue(), the request's completion
213 * routine is called to return the request to the driver. Any endpoint
214 * (except control endpoints like ep0) may have more than one transfer
215 * request queued; they complete in FIFO order. Once a gadget driver
216 * submits a request, that request may not be examined or modified until it
217 * is given back to that driver through the completion callback.
219 * Each request is turned into one or more packets. The controller driver
220 * never merges adjacent requests into the same packet. OUT transfers
221 * will sometimes use data that's already buffered in the hardware.
222 * Drivers can rely on the fact that the first byte of the request's buffer
223 * always corresponds to the first byte of some USB packet, for both
224 * IN and OUT transfers.
226 * Bulk endpoints can queue any amount of data; the transfer is packetized
227 * automatically. The last packet will be short if the request doesn't fill it
228 * out completely. Zero length packets (ZLPs) should be avoided in portable
229 * protocols since not all usb hardware can successfully handle zero length
230 * packets. (ZLPs may be explicitly written, and may be implicitly written if
231 * the request 'zero' flag is set.) Bulk endpoints may also be used
232 * for interrupt transfers; but the reverse is not true, and some endpoints
233 * won't support every interrupt transfer. (Such as 768 byte packets.)
235 * Interrupt-only endpoints are less functional than bulk endpoints, for
236 * example by not supporting queueing or not handling buffers that are
237 * larger than the endpoint's maxpacket size. They may also treat data
238 * toggle differently.
240 * Control endpoints ... after getting a setup() callback, the driver queues
241 * one response (even if it would be zero length). That enables the
242 * status ack, after transferring data as specified in the response. Setup
243 * functions may return negative error codes to generate protocol stalls.
244 * (Note that some USB device controllers disallow protocol stall responses
245 * in some cases.) When control responses are deferred (the response is
246 * written after the setup callback returns), then usb_ep_set_halt() may be
247 * used on ep0 to trigger protocol stalls. Depending on the controller,
248 * it may not be possible to trigger a status-stage protocol stall when the
249 * data stage is over, that is, from within the response's completion
252 * For periodic endpoints, like interrupt or isochronous ones, the usb host
253 * arranges to poll once per interval, and the gadget driver usually will
254 * have queued some data to transfer at that time.
256 * Note that @req's ->complete() callback must never be called from
257 * within usb_ep_queue() as that can create deadlock situations.
259 * This routine may be called in interrupt context.
261 * Returns zero, or a negative error code. Endpoints that are not enabled
262 * report errors; errors will also be
263 * reported when the usb peripheral is disconnected.
265 * If and only if @req is successfully queued (the return value is zero),
266 * @req->complete() will be called exactly once, when the Gadget core and
267 * UDC are finished with the request. When the completion function is called,
268 * control of the request is returned to the device driver which submitted it.
269 * The completion handler may then immediately free or reuse @req.
271 int usb_ep_queue(struct usb_ep *ep,
272 struct usb_request *req, gfp_t gfp_flags)
276 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
281 ret = ep->ops->queue(ep, req, gfp_flags);
284 trace_usb_ep_queue(ep, req, ret);
288 EXPORT_SYMBOL_GPL(usb_ep_queue);
291 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
292 * @ep:the endpoint associated with the request
293 * @req:the request being canceled
295 * If the request is still active on the endpoint, it is dequeued and
296 * eventually its completion routine is called (with status -ECONNRESET);
297 * else a negative error code is returned. This routine is asynchronous,
298 * that is, it may return before the completion routine runs.
300 * Note that some hardware can't clear out write fifos (to unlink the request
301 * at the head of the queue) except as part of disconnecting from usb. Such
302 * restrictions prevent drivers from supporting configuration changes,
303 * even to configuration zero (a "chapter 9" requirement).
305 * This routine may be called in interrupt context.
307 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
311 ret = ep->ops->dequeue(ep, req);
312 trace_usb_ep_dequeue(ep, req, ret);
316 EXPORT_SYMBOL_GPL(usb_ep_dequeue);
319 * usb_ep_set_halt - sets the endpoint halt feature.
320 * @ep: the non-isochronous endpoint being stalled
322 * Use this to stall an endpoint, perhaps as an error report.
323 * Except for control endpoints,
324 * the endpoint stays halted (will not stream any data) until the host
325 * clears this feature; drivers may need to empty the endpoint's request
326 * queue first, to make sure no inappropriate transfers happen.
328 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
329 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
330 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
331 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
333 * This routine may be called in interrupt context.
335 * Returns zero, or a negative error code. On success, this call sets
336 * underlying hardware state that blocks data transfers.
337 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
338 * transfer requests are still queued, or if the controller hardware
339 * (usually a FIFO) still holds bytes that the host hasn't collected.
341 int usb_ep_set_halt(struct usb_ep *ep)
345 ret = ep->ops->set_halt(ep, 1);
346 trace_usb_ep_set_halt(ep, ret);
350 EXPORT_SYMBOL_GPL(usb_ep_set_halt);
353 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
354 * @ep:the bulk or interrupt endpoint being reset
356 * Use this when responding to the standard usb "set interface" request,
357 * for endpoints that aren't reconfigured, after clearing any other state
358 * in the endpoint's i/o queue.
360 * This routine may be called in interrupt context.
362 * Returns zero, or a negative error code. On success, this call clears
363 * the underlying hardware state reflecting endpoint halt and data toggle.
364 * Note that some hardware can't support this request (like pxa2xx_udc),
365 * and accordingly can't correctly implement interface altsettings.
367 int usb_ep_clear_halt(struct usb_ep *ep)
371 ret = ep->ops->set_halt(ep, 0);
372 trace_usb_ep_clear_halt(ep, ret);
376 EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
379 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
380 * @ep: the endpoint being wedged
382 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
383 * requests. If the gadget driver clears the halt status, it will
384 * automatically unwedge the endpoint.
386 * This routine may be called in interrupt context.
388 * Returns zero on success, else negative errno.
390 int usb_ep_set_wedge(struct usb_ep *ep)
394 if (ep->ops->set_wedge)
395 ret = ep->ops->set_wedge(ep);
397 ret = ep->ops->set_halt(ep, 1);
399 trace_usb_ep_set_wedge(ep, ret);
403 EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
406 * usb_ep_fifo_status - returns number of bytes in fifo, or error
407 * @ep: the endpoint whose fifo status is being checked.
409 * FIFO endpoints may have "unclaimed data" in them in certain cases,
410 * such as after aborted transfers. Hosts may not have collected all
411 * the IN data written by the gadget driver (and reported by a request
412 * completion). The gadget driver may not have collected all the data
413 * written OUT to it by the host. Drivers that need precise handling for
414 * fault reporting or recovery may need to use this call.
416 * This routine may be called in interrupt context.
418 * This returns the number of such bytes in the fifo, or a negative
419 * errno if the endpoint doesn't use a FIFO or doesn't support such
422 int usb_ep_fifo_status(struct usb_ep *ep)
426 if (ep->ops->fifo_status)
427 ret = ep->ops->fifo_status(ep);
431 trace_usb_ep_fifo_status(ep, ret);
435 EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
438 * usb_ep_fifo_flush - flushes contents of a fifo
439 * @ep: the endpoint whose fifo is being flushed.
441 * This call may be used to flush the "unclaimed data" that may exist in
442 * an endpoint fifo after abnormal transaction terminations. The call
443 * must never be used except when endpoint is not being used for any
444 * protocol translation.
446 * This routine may be called in interrupt context.
448 void usb_ep_fifo_flush(struct usb_ep *ep)
450 if (ep->ops->fifo_flush)
451 ep->ops->fifo_flush(ep);
453 trace_usb_ep_fifo_flush(ep, 0);
455 EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
457 /* ------------------------------------------------------------------------- */
460 * usb_gadget_frame_number - returns the current frame number
461 * @gadget: controller that reports the frame number
463 * Returns the usb frame number, normally eleven bits from a SOF packet,
464 * or negative errno if this device doesn't support this capability.
466 int usb_gadget_frame_number(struct usb_gadget *gadget)
470 ret = gadget->ops->get_frame(gadget);
472 trace_usb_gadget_frame_number(gadget, ret);
476 EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
479 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
480 * @gadget: controller used to wake up the host
482 * Returns zero on success, else negative error code if the hardware
483 * doesn't support such attempts, or its support has not been enabled
484 * by the usb host. Drivers must return device descriptors that report
485 * their ability to support this, or hosts won't enable it.
487 * This may also try to use SRP to wake the host and start enumeration,
488 * even if OTG isn't otherwise in use. OTG devices may also start
489 * remote wakeup even when hosts don't explicitly enable it.
491 int usb_gadget_wakeup(struct usb_gadget *gadget)
495 if (!gadget->ops->wakeup) {
500 ret = gadget->ops->wakeup(gadget);
503 trace_usb_gadget_wakeup(gadget, ret);
507 EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
510 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
511 * @gadget:the device being declared as self-powered
513 * this affects the device status reported by the hardware driver
514 * to reflect that it now has a local power supply.
516 * returns zero on success, else negative errno.
518 int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
522 if (!gadget->ops->set_selfpowered) {
527 ret = gadget->ops->set_selfpowered(gadget, 1);
530 trace_usb_gadget_set_selfpowered(gadget, ret);
534 EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
537 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
538 * @gadget:the device being declared as bus-powered
540 * this affects the device status reported by the hardware driver.
541 * some hardware may not support bus-powered operation, in which
542 * case this feature's value can never change.
544 * returns zero on success, else negative errno.
546 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
550 if (!gadget->ops->set_selfpowered) {
555 ret = gadget->ops->set_selfpowered(gadget, 0);
558 trace_usb_gadget_clear_selfpowered(gadget, ret);
562 EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
565 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
566 * @gadget:The device which now has VBUS power.
569 * This call is used by a driver for an external transceiver (or GPIO)
570 * that detects a VBUS power session starting. Common responses include
571 * resuming the controller, activating the D+ (or D-) pullup to let the
572 * host detect that a USB device is attached, and starting to draw power
573 * (8mA or possibly more, especially after SET_CONFIGURATION).
575 * Returns zero on success, else negative errno.
577 int usb_gadget_vbus_connect(struct usb_gadget *gadget)
581 if (!gadget->ops->vbus_session) {
586 ret = gadget->ops->vbus_session(gadget, 1);
589 trace_usb_gadget_vbus_connect(gadget, ret);
593 EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
596 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
597 * @gadget:The device whose VBUS usage is being described
598 * @mA:How much current to draw, in milliAmperes. This should be twice
599 * the value listed in the configuration descriptor bMaxPower field.
601 * This call is used by gadget drivers during SET_CONFIGURATION calls,
602 * reporting how much power the device may consume. For example, this
603 * could affect how quickly batteries are recharged.
605 * Returns zero on success, else negative errno.
607 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
611 if (!gadget->ops->vbus_draw) {
616 ret = gadget->ops->vbus_draw(gadget, mA);
621 trace_usb_gadget_vbus_draw(gadget, ret);
625 EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
628 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
629 * @gadget:the device whose VBUS supply is being described
632 * This call is used by a driver for an external transceiver (or GPIO)
633 * that detects a VBUS power session ending. Common responses include
634 * reversing everything done in usb_gadget_vbus_connect().
636 * Returns zero on success, else negative errno.
638 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
642 if (!gadget->ops->vbus_session) {
647 ret = gadget->ops->vbus_session(gadget, 0);
650 trace_usb_gadget_vbus_disconnect(gadget, ret);
654 EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
657 * usb_gadget_connect - software-controlled connect to USB host
658 * @gadget:the peripheral being connected
660 * Enables the D+ (or potentially D-) pullup. The host will start
661 * enumerating this gadget when the pullup is active and a VBUS session
662 * is active (the link is powered). This pullup is always enabled unless
663 * usb_gadget_disconnect() has been used to disable it.
665 * Returns zero on success, else negative errno.
667 int usb_gadget_connect(struct usb_gadget *gadget)
671 if (!gadget->ops->pullup) {
676 if (gadget->deactivated) {
678 * If gadget is deactivated we only save new state.
679 * Gadget will be connected automatically after activation.
681 gadget->connected = true;
685 ret = gadget->ops->pullup(gadget, 1);
687 gadget->connected = 1;
690 trace_usb_gadget_connect(gadget, ret);
694 EXPORT_SYMBOL_GPL(usb_gadget_connect);
697 * usb_gadget_disconnect - software-controlled disconnect from USB host
698 * @gadget:the peripheral being disconnected
700 * Disables the D+ (or potentially D-) pullup, which the host may see
701 * as a disconnect (when a VBUS session is active). Not all systems
702 * support software pullup controls.
704 * Following a successful disconnect, invoke the ->disconnect() callback
705 * for the current gadget driver so that UDC drivers don't need to.
707 * Returns zero on success, else negative errno.
709 int usb_gadget_disconnect(struct usb_gadget *gadget)
713 if (!gadget->ops->pullup) {
718 if (gadget->deactivated) {
720 * If gadget is deactivated we only save new state.
721 * Gadget will stay disconnected after activation.
723 gadget->connected = false;
727 ret = gadget->ops->pullup(gadget, 0);
729 gadget->connected = 0;
730 gadget->udc->driver->disconnect(gadget);
734 trace_usb_gadget_disconnect(gadget, ret);
738 EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
741 * usb_gadget_deactivate - deactivate function which is not ready to work
742 * @gadget: the peripheral being deactivated
744 * This routine may be used during the gadget driver bind() call to prevent
745 * the peripheral from ever being visible to the USB host, unless later
746 * usb_gadget_activate() is called. For example, user mode components may
747 * need to be activated before the system can talk to hosts.
749 * Returns zero on success, else negative errno.
751 int usb_gadget_deactivate(struct usb_gadget *gadget)
755 if (gadget->deactivated)
758 if (gadget->connected) {
759 ret = usb_gadget_disconnect(gadget);
764 * If gadget was being connected before deactivation, we want
765 * to reconnect it in usb_gadget_activate().
767 gadget->connected = true;
769 gadget->deactivated = true;
772 trace_usb_gadget_deactivate(gadget, ret);
776 EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
779 * usb_gadget_activate - activate function which is not ready to work
780 * @gadget: the peripheral being activated
782 * This routine activates gadget which was previously deactivated with
783 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
785 * Returns zero on success, else negative errno.
787 int usb_gadget_activate(struct usb_gadget *gadget)
791 if (!gadget->deactivated)
794 gadget->deactivated = false;
797 * If gadget has been connected before deactivation, or became connected
798 * while it was being deactivated, we call usb_gadget_connect().
800 if (gadget->connected)
801 ret = usb_gadget_connect(gadget);
804 trace_usb_gadget_activate(gadget, ret);
808 EXPORT_SYMBOL_GPL(usb_gadget_activate);
810 /* ------------------------------------------------------------------------- */
812 #ifdef CONFIG_HAS_DMA
814 int usb_gadget_map_request_by_dev(struct device *dev,
815 struct usb_request *req, int is_in)
817 if (req->length == 0)
823 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
824 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
826 dev_err(dev, "failed to map SGs\n");
830 req->num_mapped_sgs = mapped;
832 if (is_vmalloc_addr(req->buf)) {
833 dev_err(dev, "buffer is not dma capable\n");
835 } else if (object_is_on_stack(req->buf)) {
836 dev_err(dev, "buffer is on stack\n");
840 req->dma = dma_map_single(dev, req->buf, req->length,
841 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
843 if (dma_mapping_error(dev, req->dma)) {
844 dev_err(dev, "failed to map buffer\n");
853 EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
855 int usb_gadget_map_request(struct usb_gadget *gadget,
856 struct usb_request *req, int is_in)
858 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
860 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
862 void usb_gadget_unmap_request_by_dev(struct device *dev,
863 struct usb_request *req, int is_in)
865 if (req->length == 0)
868 if (req->num_mapped_sgs) {
869 dma_unmap_sg(dev, req->sg, req->num_sgs,
870 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
872 req->num_mapped_sgs = 0;
873 } else if (req->dma_mapped) {
874 dma_unmap_single(dev, req->dma, req->length,
875 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
879 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
881 void usb_gadget_unmap_request(struct usb_gadget *gadget,
882 struct usb_request *req, int is_in)
884 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
886 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
888 #endif /* CONFIG_HAS_DMA */
890 /* ------------------------------------------------------------------------- */
893 * usb_gadget_giveback_request - give the request back to the gadget layer
894 * Context: in_interrupt()
896 * This is called by device controller drivers in order to return the
897 * completed request back to the gadget layer.
899 void usb_gadget_giveback_request(struct usb_ep *ep,
900 struct usb_request *req)
902 if (likely(req->status == 0))
903 usb_led_activity(USB_LED_EVENT_GADGET);
905 trace_usb_gadget_giveback_request(ep, req, 0);
907 req->complete(ep, req);
909 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
911 /* ------------------------------------------------------------------------- */
914 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
915 * in second parameter or NULL if searched endpoint not found
916 * @g: controller to check for quirk
917 * @name: name of searched endpoint
919 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
923 gadget_for_each_ep(ep, g) {
924 if (!strcmp(ep->name, name))
930 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
932 /* ------------------------------------------------------------------------- */
934 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
935 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
936 struct usb_ss_ep_comp_descriptor *ep_comp)
940 int num_req_streams = 0;
942 /* endpoint already claimed? */
946 type = usb_endpoint_type(desc);
947 max = usb_endpoint_maxp(desc);
949 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
951 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
954 if (max > ep->maxpacket_limit)
957 /* "high bandwidth" works only at high speed */
958 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp_mult(desc) > 1)
962 case USB_ENDPOINT_XFER_CONTROL:
963 /* only support ep0 for portable CONTROL traffic */
965 case USB_ENDPOINT_XFER_ISOC:
966 if (!ep->caps.type_iso)
968 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
969 if (!gadget_is_dualspeed(gadget) && max > 1023)
972 case USB_ENDPOINT_XFER_BULK:
973 if (!ep->caps.type_bulk)
975 if (ep_comp && gadget_is_superspeed(gadget)) {
976 /* Get the number of required streams from the
977 * EP companion descriptor and see if the EP
980 num_req_streams = ep_comp->bmAttributes & 0x1f;
981 if (num_req_streams > ep->max_streams)
985 case USB_ENDPOINT_XFER_INT:
986 /* Bulk endpoints handle interrupt transfers,
987 * except the toggle-quirky iso-synch kind
989 if (!ep->caps.type_int && !ep->caps.type_bulk)
991 /* INT: limit 64 bytes full speed, 1024 high/super speed */
992 if (!gadget_is_dualspeed(gadget) && max > 64)
999 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
1001 /* ------------------------------------------------------------------------- */
1003 static void usb_gadget_state_work(struct work_struct *work)
1005 struct usb_gadget *gadget = work_to_gadget(work);
1006 struct usb_udc *udc = gadget->udc;
1009 sysfs_notify(&udc->dev.kobj, NULL, "state");
1012 void usb_gadget_set_state(struct usb_gadget *gadget,
1013 enum usb_device_state state)
1015 gadget->state = state;
1016 schedule_work(&gadget->work);
1018 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
1020 /* ------------------------------------------------------------------------- */
1022 static void usb_udc_connect_control(struct usb_udc *udc)
1025 usb_gadget_connect(udc->gadget);
1027 usb_gadget_disconnect(udc->gadget);
1031 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1032 * connect or disconnect gadget
1033 * @gadget: The gadget which vbus change occurs
1034 * @status: The vbus status
1036 * The udc driver calls it when it wants to connect or disconnect gadget
1037 * according to vbus status.
1039 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1041 struct usb_udc *udc = gadget->udc;
1045 usb_udc_connect_control(udc);
1048 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1051 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1052 * @gadget: The gadget which bus reset occurs
1053 * @driver: The gadget driver we want to notify
1055 * If the udc driver has bus reset handler, it needs to call this when the bus
1056 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1057 * well as updates gadget state.
1059 void usb_gadget_udc_reset(struct usb_gadget *gadget,
1060 struct usb_gadget_driver *driver)
1062 driver->reset(gadget);
1063 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1065 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1068 * usb_gadget_udc_start - tells usb device controller to start up
1069 * @udc: The UDC to be started
1071 * This call is issued by the UDC Class driver when it's about
1072 * to register a gadget driver to the device controller, before
1073 * calling gadget driver's bind() method.
1075 * It allows the controller to be powered off until strictly
1076 * necessary to have it powered on.
1078 * Returns zero on success, else negative errno.
1080 static inline int usb_gadget_udc_start(struct usb_udc *udc)
1082 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1086 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
1087 * @gadget: The device we want to stop activity
1088 * @driver: The driver to unbind from @gadget
1090 * This call is issued by the UDC Class driver after calling
1091 * gadget driver's unbind() method.
1093 * The details are implementation specific, but it can go as
1094 * far as powering off UDC completely and disable its data
1097 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
1099 udc->gadget->ops->udc_stop(udc->gadget);
1103 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1105 * @udc: The device we want to set maximum speed
1106 * @speed: The maximum speed to allowed to run
1108 * This call is issued by the UDC Class driver before calling
1109 * usb_gadget_udc_start() in order to make sure that we don't try to
1110 * connect on speeds the gadget driver doesn't support.
1112 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1113 enum usb_device_speed speed)
1115 if (udc->gadget->ops->udc_set_speed) {
1116 enum usb_device_speed s;
1118 s = min(speed, udc->gadget->max_speed);
1119 udc->gadget->ops->udc_set_speed(udc->gadget, s);
1124 * usb_udc_release - release the usb_udc struct
1125 * @dev: the dev member within usb_udc
1127 * This is called by driver's core in order to free memory once the last
1128 * reference is released.
1130 static void usb_udc_release(struct device *dev)
1132 struct usb_udc *udc;
1134 udc = container_of(dev, struct usb_udc, dev);
1135 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1139 static const struct attribute_group *usb_udc_attr_groups[];
1141 static void usb_udc_nop_release(struct device *dev)
1143 dev_vdbg(dev, "%s\n", __func__);
1146 /* should be called with udc_lock held */
1147 static int check_pending_gadget_drivers(struct usb_udc *udc)
1149 struct usb_gadget_driver *driver;
1152 list_for_each_entry(driver, &gadget_driver_pending_list, pending)
1153 if (!driver->udc_name || strcmp(driver->udc_name,
1154 dev_name(&udc->dev)) == 0) {
1155 ret = udc_bind_to_driver(udc, driver);
1156 if (ret != -EPROBE_DEFER)
1157 list_del_init(&driver->pending);
1165 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1166 * @parent: the parent device to this udc. Usually the controller driver's
1168 * @gadget: the gadget to be added to the list.
1169 * @release: a gadget release function.
1171 * Returns zero on success, negative errno otherwise.
1172 * Calls the gadget release function in the latter case.
1174 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1175 void (*release)(struct device *dev))
1177 struct usb_udc *udc;
1180 dev_set_name(&gadget->dev, "gadget");
1181 INIT_WORK(&gadget->work, usb_gadget_state_work);
1182 gadget->dev.parent = parent;
1185 gadget->dev.release = release;
1187 gadget->dev.release = usb_udc_nop_release;
1189 device_initialize(&gadget->dev);
1191 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1193 goto err_put_gadget;
1195 device_initialize(&udc->dev);
1196 udc->dev.release = usb_udc_release;
1197 udc->dev.class = udc_class;
1198 udc->dev.groups = usb_udc_attr_groups;
1199 udc->dev.parent = parent;
1200 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
1204 ret = device_add(&gadget->dev);
1208 udc->gadget = gadget;
1211 mutex_lock(&udc_lock);
1212 list_add_tail(&udc->list, &udc_list);
1214 ret = device_add(&udc->dev);
1216 goto err_unlist_udc;
1218 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1221 /* pick up one of pending gadget drivers */
1222 ret = check_pending_gadget_drivers(udc);
1226 mutex_unlock(&udc_lock);
1231 device_del(&udc->dev);
1234 list_del(&udc->list);
1235 mutex_unlock(&udc_lock);
1237 device_del(&gadget->dev);
1240 put_device(&udc->dev);
1243 put_device(&gadget->dev);
1246 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1249 * usb_get_gadget_udc_name - get the name of the first UDC controller
1250 * This functions returns the name of the first UDC controller in the system.
1251 * Please note that this interface is usefull only for legacy drivers which
1252 * assume that there is only one UDC controller in the system and they need to
1253 * get its name before initialization. There is no guarantee that the UDC
1254 * of the returned name will be still available, when gadget driver registers
1257 * Returns pointer to string with UDC controller name on success, NULL
1258 * otherwise. Caller should kfree() returned string.
1260 char *usb_get_gadget_udc_name(void)
1262 struct usb_udc *udc;
1265 /* For now we take the first available UDC */
1266 mutex_lock(&udc_lock);
1267 list_for_each_entry(udc, &udc_list, list) {
1269 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1273 mutex_unlock(&udc_lock);
1276 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1279 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1280 * @parent: the parent device to this udc. Usually the controller
1282 * @gadget: the gadget to be added to the list
1284 * Returns zero on success, negative errno otherwise.
1286 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1288 return usb_add_gadget_udc_release(parent, gadget, NULL);
1290 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1292 static void usb_gadget_remove_driver(struct usb_udc *udc)
1294 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
1295 udc->driver->function);
1297 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1299 usb_gadget_disconnect(udc->gadget);
1300 udc->driver->unbind(udc->gadget);
1301 usb_gadget_udc_stop(udc);
1304 udc->dev.driver = NULL;
1305 udc->gadget->dev.driver = NULL;
1309 * usb_del_gadget_udc - deletes @udc from udc_list
1310 * @gadget: the gadget to be removed.
1312 * This, will call usb_gadget_unregister_driver() if
1313 * the @udc is still busy.
1315 void usb_del_gadget_udc(struct usb_gadget *gadget)
1317 struct usb_udc *udc = gadget->udc;
1322 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1324 mutex_lock(&udc_lock);
1325 list_del(&udc->list);
1328 struct usb_gadget_driver *driver = udc->driver;
1330 usb_gadget_remove_driver(udc);
1331 list_add(&driver->pending, &gadget_driver_pending_list);
1333 mutex_unlock(&udc_lock);
1335 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1336 flush_work(&gadget->work);
1337 device_unregister(&udc->dev);
1338 device_unregister(&gadget->dev);
1339 memset(&gadget->dev, 0x00, sizeof(gadget->dev));
1341 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1343 /* ------------------------------------------------------------------------- */
1345 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
1349 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
1352 udc->driver = driver;
1353 udc->dev.driver = &driver->driver;
1354 udc->gadget->dev.driver = &driver->driver;
1356 usb_gadget_udc_set_speed(udc, driver->max_speed);
1358 ret = driver->bind(udc->gadget, driver);
1361 ret = usb_gadget_udc_start(udc);
1363 driver->unbind(udc->gadget);
1366 usb_udc_connect_control(udc);
1368 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1372 dev_err(&udc->dev, "failed to start %s: %d\n",
1373 udc->driver->function, ret);
1375 udc->dev.driver = NULL;
1376 udc->gadget->dev.driver = NULL;
1380 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
1382 struct usb_udc *udc = NULL;
1385 if (!driver || !driver->bind || !driver->setup)
1388 mutex_lock(&udc_lock);
1389 if (driver->udc_name) {
1390 list_for_each_entry(udc, &udc_list, list) {
1391 ret = strcmp(driver->udc_name, dev_name(&udc->dev));
1397 else if (udc->driver)
1402 list_for_each_entry(udc, &udc_list, list) {
1403 /* For now we take the first one */
1409 if (!driver->match_existing_only) {
1410 list_add_tail(&driver->pending, &gadget_driver_pending_list);
1411 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
1416 mutex_unlock(&udc_lock);
1419 ret = udc_bind_to_driver(udc, driver);
1420 mutex_unlock(&udc_lock);
1423 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
1425 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1427 struct usb_udc *udc = NULL;
1430 if (!driver || !driver->unbind)
1433 mutex_lock(&udc_lock);
1434 list_for_each_entry(udc, &udc_list, list) {
1435 if (udc->driver == driver) {
1436 usb_gadget_remove_driver(udc);
1437 usb_gadget_set_state(udc->gadget,
1438 USB_STATE_NOTATTACHED);
1440 /* Maybe there is someone waiting for this UDC? */
1441 check_pending_gadget_drivers(udc);
1443 * For now we ignore bind errors as probably it's
1444 * not a valid reason to fail other's gadget unbind
1452 list_del(&driver->pending);
1455 mutex_unlock(&udc_lock);
1458 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1460 /* ------------------------------------------------------------------------- */
1462 static ssize_t srp_store(struct device *dev,
1463 struct device_attribute *attr, const char *buf, size_t n)
1465 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1467 if (sysfs_streq(buf, "1"))
1468 usb_gadget_wakeup(udc->gadget);
1472 static DEVICE_ATTR_WO(srp);
1474 static ssize_t soft_connect_store(struct device *dev,
1475 struct device_attribute *attr, const char *buf, size_t n)
1477 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1480 dev_err(dev, "soft-connect without a gadget driver\n");
1484 if (sysfs_streq(buf, "connect")) {
1485 usb_gadget_udc_start(udc);
1486 usb_gadget_connect(udc->gadget);
1487 } else if (sysfs_streq(buf, "disconnect")) {
1488 usb_gadget_disconnect(udc->gadget);
1489 usb_gadget_udc_stop(udc);
1491 dev_err(dev, "unsupported command '%s'\n", buf);
1497 static DEVICE_ATTR_WO(soft_connect);
1499 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1502 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1503 struct usb_gadget *gadget = udc->gadget;
1505 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1507 static DEVICE_ATTR_RO(state);
1509 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1512 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1513 struct usb_gadget_driver *drv = udc->driver;
1515 if (!drv || !drv->function)
1517 return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1519 static DEVICE_ATTR_RO(function);
1521 #define USB_UDC_SPEED_ATTR(name, param) \
1522 ssize_t name##_show(struct device *dev, \
1523 struct device_attribute *attr, char *buf) \
1525 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1526 return scnprintf(buf, PAGE_SIZE, "%s\n", \
1527 usb_speed_string(udc->gadget->param)); \
1529 static DEVICE_ATTR_RO(name)
1531 static USB_UDC_SPEED_ATTR(current_speed, speed);
1532 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1534 #define USB_UDC_ATTR(name) \
1535 ssize_t name##_show(struct device *dev, \
1536 struct device_attribute *attr, char *buf) \
1538 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1539 struct usb_gadget *gadget = udc->gadget; \
1541 return scnprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1543 static DEVICE_ATTR_RO(name)
1545 static USB_UDC_ATTR(is_otg);
1546 static USB_UDC_ATTR(is_a_peripheral);
1547 static USB_UDC_ATTR(b_hnp_enable);
1548 static USB_UDC_ATTR(a_hnp_support);
1549 static USB_UDC_ATTR(a_alt_hnp_support);
1550 static USB_UDC_ATTR(is_selfpowered);
1552 static struct attribute *usb_udc_attrs[] = {
1554 &dev_attr_soft_connect.attr,
1555 &dev_attr_state.attr,
1556 &dev_attr_function.attr,
1557 &dev_attr_current_speed.attr,
1558 &dev_attr_maximum_speed.attr,
1560 &dev_attr_is_otg.attr,
1561 &dev_attr_is_a_peripheral.attr,
1562 &dev_attr_b_hnp_enable.attr,
1563 &dev_attr_a_hnp_support.attr,
1564 &dev_attr_a_alt_hnp_support.attr,
1565 &dev_attr_is_selfpowered.attr,
1569 static const struct attribute_group usb_udc_attr_group = {
1570 .attrs = usb_udc_attrs,
1573 static const struct attribute_group *usb_udc_attr_groups[] = {
1574 &usb_udc_attr_group,
1578 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
1580 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1583 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1585 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1590 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1591 udc->driver->function);
1593 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1601 static int __init usb_udc_init(void)
1603 udc_class = class_create(THIS_MODULE, "udc");
1604 if (IS_ERR(udc_class)) {
1605 pr_err("failed to create udc class --> %ld\n",
1606 PTR_ERR(udc_class));
1607 return PTR_ERR(udc_class);
1610 udc_class->dev_uevent = usb_udc_uevent;
1613 subsys_initcall(usb_udc_init);
1615 static void __exit usb_udc_exit(void)
1617 class_destroy(udc_class);
1619 module_exit(usb_udc_exit);
1621 MODULE_DESCRIPTION("UDC Framework");
1622 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1623 MODULE_LICENSE("GPL v2");