2 * udc.c - Core UDC Framework
4 * Copyright (C) 2010 Texas Instruments
5 * Author: Felipe Balbi <balbi@ti.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 of
9 * the License as published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/list.h>
24 #include <linux/err.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/sched/task_stack.h>
27 #include <linux/workqueue.h>
29 #include <linux/usb/ch9.h>
30 #include <linux/usb/gadget.h>
31 #include <linux/usb.h>
36 * struct usb_udc - describes one usb device controller
37 * @driver - the gadget driver pointer. For use by the class code
38 * @dev - the child device to the actual controller
39 * @gadget - the gadget. For use by the class code
40 * @list - for use by the udc class driver
41 * @vbus - for udcs who care about vbus status, this value is real vbus status;
42 * for udcs who do not care about vbus status, this value is always true
44 * This represents the internal data structure which is used by the UDC-class
45 * to hold information about udc driver and gadget together.
48 struct usb_gadget_driver *driver;
49 struct usb_gadget *gadget;
51 struct list_head list;
55 static struct class *udc_class;
56 static LIST_HEAD(udc_list);
57 static LIST_HEAD(gadget_driver_pending_list);
58 static DEFINE_MUTEX(udc_lock);
60 static int udc_bind_to_driver(struct usb_udc *udc,
61 struct usb_gadget_driver *driver);
63 /* ------------------------------------------------------------------------- */
66 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
67 * @ep:the endpoint being configured
68 * @maxpacket_limit:value of maximum packet size limit
70 * This function should be used only in UDC drivers to initialize endpoint
71 * (usually in probe function).
73 void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
74 unsigned maxpacket_limit)
76 ep->maxpacket_limit = maxpacket_limit;
77 ep->maxpacket = maxpacket_limit;
79 trace_usb_ep_set_maxpacket_limit(ep, 0);
81 EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
84 * usb_ep_enable - configure endpoint, making it usable
85 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
86 * drivers discover endpoints through the ep_list of a usb_gadget.
88 * When configurations are set, or when interface settings change, the driver
89 * will enable or disable the relevant endpoints. while it is enabled, an
90 * endpoint may be used for i/o until the driver receives a disconnect() from
91 * the host or until the endpoint is disabled.
93 * the ep0 implementation (which calls this routine) must ensure that the
94 * hardware capabilities of each endpoint match the descriptor provided
95 * for it. for example, an endpoint named "ep2in-bulk" would be usable
96 * for interrupt transfers as well as bulk, but it likely couldn't be used
97 * for iso transfers or for endpoint 14. some endpoints are fully
98 * configurable, with more generic names like "ep-a". (remember that for
99 * USB, "in" means "towards the USB master".)
101 * returns zero, or a negative error code.
103 int usb_ep_enable(struct usb_ep *ep)
110 ret = ep->ops->enable(ep, ep->desc);
117 trace_usb_ep_enable(ep, ret);
121 EXPORT_SYMBOL_GPL(usb_ep_enable);
124 * usb_ep_disable - endpoint is no longer usable
125 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
127 * no other task may be using this endpoint when this is called.
128 * any pending and uncompleted requests will complete with status
129 * indicating disconnect (-ESHUTDOWN) before this call returns.
130 * gadget drivers must call usb_ep_enable() again before queueing
131 * requests to the endpoint.
133 * returns zero, or a negative error code.
135 int usb_ep_disable(struct usb_ep *ep)
142 ret = ep->ops->disable(ep);
149 trace_usb_ep_disable(ep, ret);
153 EXPORT_SYMBOL_GPL(usb_ep_disable);
156 * usb_ep_alloc_request - allocate a request object to use with this endpoint
157 * @ep:the endpoint to be used with with the request
158 * @gfp_flags:GFP_* flags to use
160 * Request objects must be allocated with this call, since they normally
161 * need controller-specific setup and may even need endpoint-specific
162 * resources such as allocation of DMA descriptors.
163 * Requests may be submitted with usb_ep_queue(), and receive a single
164 * completion callback. Free requests with usb_ep_free_request(), when
165 * they are no longer needed.
167 * Returns the request, or null if one could not be allocated.
169 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
172 struct usb_request *req = NULL;
174 req = ep->ops->alloc_request(ep, gfp_flags);
176 trace_usb_ep_alloc_request(ep, req, req ? 0 : -ENOMEM);
180 EXPORT_SYMBOL_GPL(usb_ep_alloc_request);
183 * usb_ep_free_request - frees a request object
184 * @ep:the endpoint associated with the request
185 * @req:the request being freed
187 * Reverses the effect of usb_ep_alloc_request().
188 * Caller guarantees the request is not queued, and that it will
189 * no longer be requeued (or otherwise used).
191 void usb_ep_free_request(struct usb_ep *ep,
192 struct usb_request *req)
194 ep->ops->free_request(ep, req);
195 trace_usb_ep_free_request(ep, req, 0);
197 EXPORT_SYMBOL_GPL(usb_ep_free_request);
200 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
201 * @ep:the endpoint associated with the request
202 * @req:the request being submitted
203 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
204 * pre-allocate all necessary memory with the request.
206 * This tells the device controller to perform the specified request through
207 * that endpoint (reading or writing a buffer). When the request completes,
208 * including being canceled by usb_ep_dequeue(), the request's completion
209 * routine is called to return the request to the driver. Any endpoint
210 * (except control endpoints like ep0) may have more than one transfer
211 * request queued; they complete in FIFO order. Once a gadget driver
212 * submits a request, that request may not be examined or modified until it
213 * is given back to that driver through the completion callback.
215 * Each request is turned into one or more packets. The controller driver
216 * never merges adjacent requests into the same packet. OUT transfers
217 * will sometimes use data that's already buffered in the hardware.
218 * Drivers can rely on the fact that the first byte of the request's buffer
219 * always corresponds to the first byte of some USB packet, for both
220 * IN and OUT transfers.
222 * Bulk endpoints can queue any amount of data; the transfer is packetized
223 * automatically. The last packet will be short if the request doesn't fill it
224 * out completely. Zero length packets (ZLPs) should be avoided in portable
225 * protocols since not all usb hardware can successfully handle zero length
226 * packets. (ZLPs may be explicitly written, and may be implicitly written if
227 * the request 'zero' flag is set.) Bulk endpoints may also be used
228 * for interrupt transfers; but the reverse is not true, and some endpoints
229 * won't support every interrupt transfer. (Such as 768 byte packets.)
231 * Interrupt-only endpoints are less functional than bulk endpoints, for
232 * example by not supporting queueing or not handling buffers that are
233 * larger than the endpoint's maxpacket size. They may also treat data
234 * toggle differently.
236 * Control endpoints ... after getting a setup() callback, the driver queues
237 * one response (even if it would be zero length). That enables the
238 * status ack, after transferring data as specified in the response. Setup
239 * functions may return negative error codes to generate protocol stalls.
240 * (Note that some USB device controllers disallow protocol stall responses
241 * in some cases.) When control responses are deferred (the response is
242 * written after the setup callback returns), then usb_ep_set_halt() may be
243 * used on ep0 to trigger protocol stalls. Depending on the controller,
244 * it may not be possible to trigger a status-stage protocol stall when the
245 * data stage is over, that is, from within the response's completion
248 * For periodic endpoints, like interrupt or isochronous ones, the usb host
249 * arranges to poll once per interval, and the gadget driver usually will
250 * have queued some data to transfer at that time.
252 * Returns zero, or a negative error code. Endpoints that are not enabled
253 * report errors; errors will also be
254 * reported when the usb peripheral is disconnected.
256 int usb_ep_queue(struct usb_ep *ep,
257 struct usb_request *req, gfp_t gfp_flags)
261 if (WARN_ON_ONCE(!ep->enabled && ep->address)) {
266 ret = ep->ops->queue(ep, req, gfp_flags);
269 trace_usb_ep_queue(ep, req, ret);
273 EXPORT_SYMBOL_GPL(usb_ep_queue);
276 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
277 * @ep:the endpoint associated with the request
278 * @req:the request being canceled
280 * If the request is still active on the endpoint, it is dequeued and its
281 * completion routine is called (with status -ECONNRESET); else a negative
282 * error code is returned. This is guaranteed to happen before the call to
283 * usb_ep_dequeue() returns.
285 * Note that some hardware can't clear out write fifos (to unlink the request
286 * at the head of the queue) except as part of disconnecting from usb. Such
287 * restrictions prevent drivers from supporting configuration changes,
288 * even to configuration zero (a "chapter 9" requirement).
290 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
294 ret = ep->ops->dequeue(ep, req);
295 trace_usb_ep_dequeue(ep, req, ret);
299 EXPORT_SYMBOL_GPL(usb_ep_dequeue);
302 * usb_ep_set_halt - sets the endpoint halt feature.
303 * @ep: the non-isochronous endpoint being stalled
305 * Use this to stall an endpoint, perhaps as an error report.
306 * Except for control endpoints,
307 * the endpoint stays halted (will not stream any data) until the host
308 * clears this feature; drivers may need to empty the endpoint's request
309 * queue first, to make sure no inappropriate transfers happen.
311 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
312 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
313 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
314 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
316 * Returns zero, or a negative error code. On success, this call sets
317 * underlying hardware state that blocks data transfers.
318 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
319 * transfer requests are still queued, or if the controller hardware
320 * (usually a FIFO) still holds bytes that the host hasn't collected.
322 int usb_ep_set_halt(struct usb_ep *ep)
326 ret = ep->ops->set_halt(ep, 1);
327 trace_usb_ep_set_halt(ep, ret);
331 EXPORT_SYMBOL_GPL(usb_ep_set_halt);
334 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
335 * @ep:the bulk or interrupt endpoint being reset
337 * Use this when responding to the standard usb "set interface" request,
338 * for endpoints that aren't reconfigured, after clearing any other state
339 * in the endpoint's i/o queue.
341 * Returns zero, or a negative error code. On success, this call clears
342 * the underlying hardware state reflecting endpoint halt and data toggle.
343 * Note that some hardware can't support this request (like pxa2xx_udc),
344 * and accordingly can't correctly implement interface altsettings.
346 int usb_ep_clear_halt(struct usb_ep *ep)
350 ret = ep->ops->set_halt(ep, 0);
351 trace_usb_ep_clear_halt(ep, ret);
355 EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
358 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
359 * @ep: the endpoint being wedged
361 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
362 * requests. If the gadget driver clears the halt status, it will
363 * automatically unwedge the endpoint.
365 * Returns zero on success, else negative errno.
367 int usb_ep_set_wedge(struct usb_ep *ep)
371 if (ep->ops->set_wedge)
372 ret = ep->ops->set_wedge(ep);
374 ret = ep->ops->set_halt(ep, 1);
376 trace_usb_ep_set_wedge(ep, ret);
380 EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
383 * usb_ep_fifo_status - returns number of bytes in fifo, or error
384 * @ep: the endpoint whose fifo status is being checked.
386 * FIFO endpoints may have "unclaimed data" in them in certain cases,
387 * such as after aborted transfers. Hosts may not have collected all
388 * the IN data written by the gadget driver (and reported by a request
389 * completion). The gadget driver may not have collected all the data
390 * written OUT to it by the host. Drivers that need precise handling for
391 * fault reporting or recovery may need to use this call.
393 * This returns the number of such bytes in the fifo, or a negative
394 * errno if the endpoint doesn't use a FIFO or doesn't support such
397 int usb_ep_fifo_status(struct usb_ep *ep)
401 if (ep->ops->fifo_status)
402 ret = ep->ops->fifo_status(ep);
406 trace_usb_ep_fifo_status(ep, ret);
410 EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
413 * usb_ep_fifo_flush - flushes contents of a fifo
414 * @ep: the endpoint whose fifo is being flushed.
416 * This call may be used to flush the "unclaimed data" that may exist in
417 * an endpoint fifo after abnormal transaction terminations. The call
418 * must never be used except when endpoint is not being used for any
419 * protocol translation.
421 void usb_ep_fifo_flush(struct usb_ep *ep)
423 if (ep->ops->fifo_flush)
424 ep->ops->fifo_flush(ep);
426 trace_usb_ep_fifo_flush(ep, 0);
428 EXPORT_SYMBOL_GPL(usb_ep_fifo_flush);
430 /* ------------------------------------------------------------------------- */
433 * usb_gadget_frame_number - returns the current frame number
434 * @gadget: controller that reports the frame number
436 * Returns the usb frame number, normally eleven bits from a SOF packet,
437 * or negative errno if this device doesn't support this capability.
439 int usb_gadget_frame_number(struct usb_gadget *gadget)
443 ret = gadget->ops->get_frame(gadget);
445 trace_usb_gadget_frame_number(gadget, ret);
449 EXPORT_SYMBOL_GPL(usb_gadget_frame_number);
452 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
453 * @gadget: controller used to wake up the host
455 * Returns zero on success, else negative error code if the hardware
456 * doesn't support such attempts, or its support has not been enabled
457 * by the usb host. Drivers must return device descriptors that report
458 * their ability to support this, or hosts won't enable it.
460 * This may also try to use SRP to wake the host and start enumeration,
461 * even if OTG isn't otherwise in use. OTG devices may also start
462 * remote wakeup even when hosts don't explicitly enable it.
464 int usb_gadget_wakeup(struct usb_gadget *gadget)
468 if (!gadget->ops->wakeup) {
473 ret = gadget->ops->wakeup(gadget);
476 trace_usb_gadget_wakeup(gadget, ret);
480 EXPORT_SYMBOL_GPL(usb_gadget_wakeup);
483 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
484 * @gadget:the device being declared as self-powered
486 * this affects the device status reported by the hardware driver
487 * to reflect that it now has a local power supply.
489 * returns zero on success, else negative errno.
491 int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
495 if (!gadget->ops->set_selfpowered) {
500 ret = gadget->ops->set_selfpowered(gadget, 1);
503 trace_usb_gadget_set_selfpowered(gadget, ret);
507 EXPORT_SYMBOL_GPL(usb_gadget_set_selfpowered);
510 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
511 * @gadget:the device being declared as bus-powered
513 * this affects the device status reported by the hardware driver.
514 * some hardware may not support bus-powered operation, in which
515 * case this feature's value can never change.
517 * returns zero on success, else negative errno.
519 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
523 if (!gadget->ops->set_selfpowered) {
528 ret = gadget->ops->set_selfpowered(gadget, 0);
531 trace_usb_gadget_clear_selfpowered(gadget, ret);
535 EXPORT_SYMBOL_GPL(usb_gadget_clear_selfpowered);
538 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
539 * @gadget:The device which now has VBUS power.
542 * This call is used by a driver for an external transceiver (or GPIO)
543 * that detects a VBUS power session starting. Common responses include
544 * resuming the controller, activating the D+ (or D-) pullup to let the
545 * host detect that a USB device is attached, and starting to draw power
546 * (8mA or possibly more, especially after SET_CONFIGURATION).
548 * Returns zero on success, else negative errno.
550 int usb_gadget_vbus_connect(struct usb_gadget *gadget)
554 if (!gadget->ops->vbus_session) {
559 ret = gadget->ops->vbus_session(gadget, 1);
562 trace_usb_gadget_vbus_connect(gadget, ret);
566 EXPORT_SYMBOL_GPL(usb_gadget_vbus_connect);
569 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
570 * @gadget:The device whose VBUS usage is being described
571 * @mA:How much current to draw, in milliAmperes. This should be twice
572 * the value listed in the configuration descriptor bMaxPower field.
574 * This call is used by gadget drivers during SET_CONFIGURATION calls,
575 * reporting how much power the device may consume. For example, this
576 * could affect how quickly batteries are recharged.
578 * Returns zero on success, else negative errno.
580 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
584 if (!gadget->ops->vbus_draw) {
589 ret = gadget->ops->vbus_draw(gadget, mA);
594 trace_usb_gadget_vbus_draw(gadget, ret);
598 EXPORT_SYMBOL_GPL(usb_gadget_vbus_draw);
601 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
602 * @gadget:the device whose VBUS supply is being described
605 * This call is used by a driver for an external transceiver (or GPIO)
606 * that detects a VBUS power session ending. Common responses include
607 * reversing everything done in usb_gadget_vbus_connect().
609 * Returns zero on success, else negative errno.
611 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
615 if (!gadget->ops->vbus_session) {
620 ret = gadget->ops->vbus_session(gadget, 0);
623 trace_usb_gadget_vbus_disconnect(gadget, ret);
627 EXPORT_SYMBOL_GPL(usb_gadget_vbus_disconnect);
630 * usb_gadget_connect - software-controlled connect to USB host
631 * @gadget:the peripheral being connected
633 * Enables the D+ (or potentially D-) pullup. The host will start
634 * enumerating this gadget when the pullup is active and a VBUS session
635 * is active (the link is powered). This pullup is always enabled unless
636 * usb_gadget_disconnect() has been used to disable it.
638 * Returns zero on success, else negative errno.
640 int usb_gadget_connect(struct usb_gadget *gadget)
644 if (!gadget->ops->pullup) {
649 if (gadget->deactivated) {
651 * If gadget is deactivated we only save new state.
652 * Gadget will be connected automatically after activation.
654 gadget->connected = true;
658 ret = gadget->ops->pullup(gadget, 1);
660 gadget->connected = 1;
663 trace_usb_gadget_connect(gadget, ret);
667 EXPORT_SYMBOL_GPL(usb_gadget_connect);
670 * usb_gadget_disconnect - software-controlled disconnect from USB host
671 * @gadget:the peripheral being disconnected
673 * Disables the D+ (or potentially D-) pullup, which the host may see
674 * as a disconnect (when a VBUS session is active). Not all systems
675 * support software pullup controls.
677 * Returns zero on success, else negative errno.
679 int usb_gadget_disconnect(struct usb_gadget *gadget)
683 if (!gadget->ops->pullup) {
688 if (gadget->deactivated) {
690 * If gadget is deactivated we only save new state.
691 * Gadget will stay disconnected after activation.
693 gadget->connected = false;
697 ret = gadget->ops->pullup(gadget, 0);
699 gadget->connected = 0;
702 trace_usb_gadget_disconnect(gadget, ret);
706 EXPORT_SYMBOL_GPL(usb_gadget_disconnect);
709 * usb_gadget_deactivate - deactivate function which is not ready to work
710 * @gadget: the peripheral being deactivated
712 * This routine may be used during the gadget driver bind() call to prevent
713 * the peripheral from ever being visible to the USB host, unless later
714 * usb_gadget_activate() is called. For example, user mode components may
715 * need to be activated before the system can talk to hosts.
717 * Returns zero on success, else negative errno.
719 int usb_gadget_deactivate(struct usb_gadget *gadget)
723 if (gadget->deactivated)
726 if (gadget->connected) {
727 ret = usb_gadget_disconnect(gadget);
732 * If gadget was being connected before deactivation, we want
733 * to reconnect it in usb_gadget_activate().
735 gadget->connected = true;
737 gadget->deactivated = true;
740 trace_usb_gadget_deactivate(gadget, ret);
744 EXPORT_SYMBOL_GPL(usb_gadget_deactivate);
747 * usb_gadget_activate - activate function which is not ready to work
748 * @gadget: the peripheral being activated
750 * This routine activates gadget which was previously deactivated with
751 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
753 * Returns zero on success, else negative errno.
755 int usb_gadget_activate(struct usb_gadget *gadget)
759 if (!gadget->deactivated)
762 gadget->deactivated = false;
765 * If gadget has been connected before deactivation, or became connected
766 * while it was being deactivated, we call usb_gadget_connect().
768 if (gadget->connected)
769 ret = usb_gadget_connect(gadget);
772 trace_usb_gadget_activate(gadget, ret);
776 EXPORT_SYMBOL_GPL(usb_gadget_activate);
778 /* ------------------------------------------------------------------------- */
780 #ifdef CONFIG_HAS_DMA
782 int usb_gadget_map_request_by_dev(struct device *dev,
783 struct usb_request *req, int is_in)
785 if (req->length == 0)
791 mapped = dma_map_sg(dev, req->sg, req->num_sgs,
792 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
794 dev_err(dev, "failed to map SGs\n");
798 req->num_mapped_sgs = mapped;
800 if (is_vmalloc_addr(req->buf)) {
801 dev_err(dev, "buffer is not dma capable\n");
803 } else if (object_is_on_stack(req->buf)) {
804 dev_err(dev, "buffer is on stack\n");
808 req->dma = dma_map_single(dev, req->buf, req->length,
809 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
811 if (dma_mapping_error(dev, req->dma)) {
812 dev_err(dev, "failed to map buffer\n");
821 EXPORT_SYMBOL_GPL(usb_gadget_map_request_by_dev);
823 int usb_gadget_map_request(struct usb_gadget *gadget,
824 struct usb_request *req, int is_in)
826 return usb_gadget_map_request_by_dev(gadget->dev.parent, req, is_in);
828 EXPORT_SYMBOL_GPL(usb_gadget_map_request);
830 void usb_gadget_unmap_request_by_dev(struct device *dev,
831 struct usb_request *req, int is_in)
833 if (req->length == 0)
836 if (req->num_mapped_sgs) {
837 dma_unmap_sg(dev, req->sg, req->num_sgs,
838 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
840 req->num_mapped_sgs = 0;
841 } else if (req->dma_mapped) {
842 dma_unmap_single(dev, req->dma, req->length,
843 is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
847 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev);
849 void usb_gadget_unmap_request(struct usb_gadget *gadget,
850 struct usb_request *req, int is_in)
852 usb_gadget_unmap_request_by_dev(gadget->dev.parent, req, is_in);
854 EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
856 #endif /* CONFIG_HAS_DMA */
858 /* ------------------------------------------------------------------------- */
861 * usb_gadget_giveback_request - give the request back to the gadget layer
862 * Context: in_interrupt()
864 * This is called by device controller drivers in order to return the
865 * completed request back to the gadget layer.
867 void usb_gadget_giveback_request(struct usb_ep *ep,
868 struct usb_request *req)
870 if (likely(req->status == 0))
871 usb_led_activity(USB_LED_EVENT_GADGET);
873 trace_usb_gadget_giveback_request(ep, req, 0);
875 req->complete(ep, req);
877 EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
879 /* ------------------------------------------------------------------------- */
882 * gadget_find_ep_by_name - returns ep whose name is the same as sting passed
883 * in second parameter or NULL if searched endpoint not found
884 * @g: controller to check for quirk
885 * @name: name of searched endpoint
887 struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, const char *name)
891 gadget_for_each_ep(ep, g) {
892 if (!strcmp(ep->name, name))
898 EXPORT_SYMBOL_GPL(gadget_find_ep_by_name);
900 /* ------------------------------------------------------------------------- */
902 int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
903 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
904 struct usb_ss_ep_comp_descriptor *ep_comp)
908 int num_req_streams = 0;
910 /* endpoint already claimed? */
914 type = usb_endpoint_type(desc);
915 max = 0x7ff & usb_endpoint_maxp(desc);
917 if (usb_endpoint_dir_in(desc) && !ep->caps.dir_in)
919 if (usb_endpoint_dir_out(desc) && !ep->caps.dir_out)
922 if (max > ep->maxpacket_limit)
925 /* "high bandwidth" works only at high speed */
926 if (!gadget_is_dualspeed(gadget) && usb_endpoint_maxp(desc) & (3<<11))
930 case USB_ENDPOINT_XFER_CONTROL:
931 /* only support ep0 for portable CONTROL traffic */
933 case USB_ENDPOINT_XFER_ISOC:
934 if (!ep->caps.type_iso)
936 /* ISO: limit 1023 bytes full speed, 1024 high/super speed */
937 if (!gadget_is_dualspeed(gadget) && max > 1023)
940 case USB_ENDPOINT_XFER_BULK:
941 if (!ep->caps.type_bulk)
943 if (ep_comp && gadget_is_superspeed(gadget)) {
944 /* Get the number of required streams from the
945 * EP companion descriptor and see if the EP
948 num_req_streams = ep_comp->bmAttributes & 0x1f;
949 if (num_req_streams > ep->max_streams)
953 case USB_ENDPOINT_XFER_INT:
954 /* Bulk endpoints handle interrupt transfers,
955 * except the toggle-quirky iso-synch kind
957 if (!ep->caps.type_int && !ep->caps.type_bulk)
959 /* INT: limit 64 bytes full speed, 1024 high/super speed */
960 if (!gadget_is_dualspeed(gadget) && max > 64)
967 EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
969 /* ------------------------------------------------------------------------- */
971 static void usb_gadget_state_work(struct work_struct *work)
973 struct usb_gadget *gadget = work_to_gadget(work);
974 struct usb_udc *udc = gadget->udc;
977 sysfs_notify(&udc->dev.kobj, NULL, "state");
980 void usb_gadget_set_state(struct usb_gadget *gadget,
981 enum usb_device_state state)
983 gadget->state = state;
984 schedule_work(&gadget->work);
986 EXPORT_SYMBOL_GPL(usb_gadget_set_state);
988 /* ------------------------------------------------------------------------- */
990 static void usb_udc_connect_control(struct usb_udc *udc)
993 usb_gadget_connect(udc->gadget);
995 usb_gadget_disconnect(udc->gadget);
999 * usb_udc_vbus_handler - updates the udc core vbus status, and try to
1000 * connect or disconnect gadget
1001 * @gadget: The gadget which vbus change occurs
1002 * @status: The vbus status
1004 * The udc driver calls it when it wants to connect or disconnect gadget
1005 * according to vbus status.
1007 void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status)
1009 struct usb_udc *udc = gadget->udc;
1013 usb_udc_connect_control(udc);
1016 EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
1019 * usb_gadget_udc_reset - notifies the udc core that bus reset occurs
1020 * @gadget: The gadget which bus reset occurs
1021 * @driver: The gadget driver we want to notify
1023 * If the udc driver has bus reset handler, it needs to call this when the bus
1024 * reset occurs, it notifies the gadget driver that the bus reset occurs as
1025 * well as updates gadget state.
1027 void usb_gadget_udc_reset(struct usb_gadget *gadget,
1028 struct usb_gadget_driver *driver)
1030 driver->reset(gadget);
1031 usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
1033 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);
1036 * usb_gadget_udc_start - tells usb device controller to start up
1037 * @udc: The UDC to be started
1039 * This call is issued by the UDC Class driver when it's about
1040 * to register a gadget driver to the device controller, before
1041 * calling gadget driver's bind() method.
1043 * It allows the controller to be powered off until strictly
1044 * necessary to have it powered on.
1046 * Returns zero on success, else negative errno.
1048 static inline int usb_gadget_udc_start(struct usb_udc *udc)
1050 return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
1054 * usb_gadget_udc_stop - tells usb device controller we don't need it anymore
1055 * @gadget: The device we want to stop activity
1056 * @driver: The driver to unbind from @gadget
1058 * This call is issued by the UDC Class driver after calling
1059 * gadget driver's unbind() method.
1061 * The details are implementation specific, but it can go as
1062 * far as powering off UDC completely and disable its data
1065 static inline void usb_gadget_udc_stop(struct usb_udc *udc)
1067 udc->gadget->ops->udc_stop(udc->gadget);
1071 * usb_gadget_udc_set_speed - tells usb device controller speed supported by
1073 * @udc: The device we want to set maximum speed
1074 * @speed: The maximum speed to allowed to run
1076 * This call is issued by the UDC Class driver before calling
1077 * usb_gadget_udc_start() in order to make sure that we don't try to
1078 * connect on speeds the gadget driver doesn't support.
1080 static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
1081 enum usb_device_speed speed)
1083 if (udc->gadget->ops->udc_set_speed)
1084 udc->gadget->ops->udc_set_speed(udc->gadget, speed);
1088 * usb_udc_release - release the usb_udc struct
1089 * @dev: the dev member within usb_udc
1091 * This is called by driver's core in order to free memory once the last
1092 * reference is released.
1094 static void usb_udc_release(struct device *dev)
1096 struct usb_udc *udc;
1098 udc = container_of(dev, struct usb_udc, dev);
1099 dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
1103 static const struct attribute_group *usb_udc_attr_groups[];
1105 static void usb_udc_nop_release(struct device *dev)
1107 dev_vdbg(dev, "%s\n", __func__);
1110 /* should be called with udc_lock held */
1111 static int check_pending_gadget_drivers(struct usb_udc *udc)
1113 struct usb_gadget_driver *driver;
1116 list_for_each_entry(driver, &gadget_driver_pending_list, pending)
1117 if (!driver->udc_name || strcmp(driver->udc_name,
1118 dev_name(&udc->dev)) == 0) {
1119 ret = udc_bind_to_driver(udc, driver);
1120 if (ret != -EPROBE_DEFER)
1121 list_del(&driver->pending);
1129 * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
1130 * @parent: the parent device to this udc. Usually the controller driver's
1132 * @gadget: the gadget to be added to the list.
1133 * @release: a gadget release function.
1135 * Returns zero on success, negative errno otherwise.
1136 * Calls the gadget release function in the latter case.
1138 int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
1139 void (*release)(struct device *dev))
1141 struct usb_udc *udc;
1144 dev_set_name(&gadget->dev, "gadget");
1145 INIT_WORK(&gadget->work, usb_gadget_state_work);
1146 gadget->dev.parent = parent;
1149 gadget->dev.release = release;
1151 gadget->dev.release = usb_udc_nop_release;
1153 device_initialize(&gadget->dev);
1155 udc = kzalloc(sizeof(*udc), GFP_KERNEL);
1159 ret = device_add(&gadget->dev);
1163 device_initialize(&udc->dev);
1164 udc->dev.release = usb_udc_release;
1165 udc->dev.class = udc_class;
1166 udc->dev.groups = usb_udc_attr_groups;
1167 udc->dev.parent = parent;
1168 ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
1172 udc->gadget = gadget;
1175 mutex_lock(&udc_lock);
1176 list_add_tail(&udc->list, &udc_list);
1178 ret = device_add(&udc->dev);
1182 usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED);
1185 /* pick up one of pending gadget drivers */
1186 ret = check_pending_gadget_drivers(udc);
1190 mutex_unlock(&udc_lock);
1195 device_del(&udc->dev);
1198 list_del(&udc->list);
1199 mutex_unlock(&udc_lock);
1202 put_device(&udc->dev);
1203 device_del(&gadget->dev);
1209 put_device(&gadget->dev);
1212 EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
1215 * usb_get_gadget_udc_name - get the name of the first UDC controller
1216 * This functions returns the name of the first UDC controller in the system.
1217 * Please note that this interface is usefull only for legacy drivers which
1218 * assume that there is only one UDC controller in the system and they need to
1219 * get its name before initialization. There is no guarantee that the UDC
1220 * of the returned name will be still available, when gadget driver registers
1223 * Returns pointer to string with UDC controller name on success, NULL
1224 * otherwise. Caller should kfree() returned string.
1226 char *usb_get_gadget_udc_name(void)
1228 struct usb_udc *udc;
1231 /* For now we take the first available UDC */
1232 mutex_lock(&udc_lock);
1233 list_for_each_entry(udc, &udc_list, list) {
1235 name = kstrdup(udc->gadget->name, GFP_KERNEL);
1239 mutex_unlock(&udc_lock);
1242 EXPORT_SYMBOL_GPL(usb_get_gadget_udc_name);
1245 * usb_add_gadget_udc - adds a new gadget to the udc class driver list
1246 * @parent: the parent device to this udc. Usually the controller
1248 * @gadget: the gadget to be added to the list
1250 * Returns zero on success, negative errno otherwise.
1252 int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
1254 return usb_add_gadget_udc_release(parent, gadget, NULL);
1256 EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
1258 static void usb_gadget_remove_driver(struct usb_udc *udc)
1260 dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
1261 udc->driver->function);
1263 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1265 usb_gadget_disconnect(udc->gadget);
1266 udc->driver->disconnect(udc->gadget);
1267 udc->driver->unbind(udc->gadget);
1268 usb_gadget_udc_stop(udc);
1271 udc->dev.driver = NULL;
1272 udc->gadget->dev.driver = NULL;
1276 * usb_del_gadget_udc - deletes @udc from udc_list
1277 * @gadget: the gadget to be removed.
1279 * This, will call usb_gadget_unregister_driver() if
1280 * the @udc is still busy.
1282 void usb_del_gadget_udc(struct usb_gadget *gadget)
1284 struct usb_udc *udc = gadget->udc;
1289 dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
1291 mutex_lock(&udc_lock);
1292 list_del(&udc->list);
1295 struct usb_gadget_driver *driver = udc->driver;
1297 usb_gadget_remove_driver(udc);
1298 list_add(&driver->pending, &gadget_driver_pending_list);
1300 mutex_unlock(&udc_lock);
1302 kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
1303 flush_work(&gadget->work);
1304 device_unregister(&udc->dev);
1305 device_unregister(&gadget->dev);
1306 memset(&gadget->dev, 0x00, sizeof(gadget->dev));
1308 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
1310 /* ------------------------------------------------------------------------- */
1312 static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver)
1316 dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
1319 udc->driver = driver;
1320 udc->dev.driver = &driver->driver;
1321 udc->gadget->dev.driver = &driver->driver;
1323 if (driver->max_speed < udc->gadget->max_speed)
1324 usb_gadget_udc_set_speed(udc, driver->max_speed);
1326 ret = driver->bind(udc->gadget, driver);
1329 ret = usb_gadget_udc_start(udc);
1331 driver->unbind(udc->gadget);
1334 usb_udc_connect_control(udc);
1336 kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
1340 dev_err(&udc->dev, "failed to start %s: %d\n",
1341 udc->driver->function, ret);
1343 udc->dev.driver = NULL;
1344 udc->gadget->dev.driver = NULL;
1348 int usb_gadget_probe_driver(struct usb_gadget_driver *driver)
1350 struct usb_udc *udc = NULL;
1353 if (!driver || !driver->bind || !driver->setup)
1356 mutex_lock(&udc_lock);
1357 if (driver->udc_name) {
1358 list_for_each_entry(udc, &udc_list, list) {
1359 ret = strcmp(driver->udc_name, dev_name(&udc->dev));
1365 else if (udc->driver)
1370 list_for_each_entry(udc, &udc_list, list) {
1371 /* For now we take the first one */
1377 if (!driver->match_existing_only) {
1378 list_add_tail(&driver->pending, &gadget_driver_pending_list);
1379 pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n",
1384 mutex_unlock(&udc_lock);
1387 ret = udc_bind_to_driver(udc, driver);
1388 mutex_unlock(&udc_lock);
1391 EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
1393 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
1395 struct usb_udc *udc = NULL;
1398 if (!driver || !driver->unbind)
1401 mutex_lock(&udc_lock);
1402 list_for_each_entry(udc, &udc_list, list) {
1403 if (udc->driver == driver) {
1404 usb_gadget_remove_driver(udc);
1405 usb_gadget_set_state(udc->gadget,
1406 USB_STATE_NOTATTACHED);
1408 /* Maybe there is someone waiting for this UDC? */
1409 check_pending_gadget_drivers(udc);
1411 * For now we ignore bind errors as probably it's
1412 * not a valid reason to fail other's gadget unbind
1420 list_del(&driver->pending);
1423 mutex_unlock(&udc_lock);
1426 EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
1428 /* ------------------------------------------------------------------------- */
1430 static ssize_t usb_udc_srp_store(struct device *dev,
1431 struct device_attribute *attr, const char *buf, size_t n)
1433 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1435 if (sysfs_streq(buf, "1"))
1436 usb_gadget_wakeup(udc->gadget);
1440 static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
1442 static ssize_t usb_udc_softconn_store(struct device *dev,
1443 struct device_attribute *attr, const char *buf, size_t n)
1445 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1448 dev_err(dev, "soft-connect without a gadget driver\n");
1452 if (sysfs_streq(buf, "connect")) {
1453 usb_gadget_udc_start(udc);
1454 usb_gadget_connect(udc->gadget);
1455 } else if (sysfs_streq(buf, "disconnect")) {
1456 usb_gadget_disconnect(udc->gadget);
1457 udc->driver->disconnect(udc->gadget);
1458 usb_gadget_udc_stop(udc);
1460 dev_err(dev, "unsupported command '%s'\n", buf);
1466 static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
1468 static ssize_t state_show(struct device *dev, struct device_attribute *attr,
1471 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1472 struct usb_gadget *gadget = udc->gadget;
1474 return sprintf(buf, "%s\n", usb_state_string(gadget->state));
1476 static DEVICE_ATTR_RO(state);
1478 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
1481 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1482 struct usb_gadget_driver *drv = udc->driver;
1484 if (!drv || !drv->function)
1486 return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
1488 static DEVICE_ATTR_RO(function);
1490 #define USB_UDC_SPEED_ATTR(name, param) \
1491 ssize_t name##_show(struct device *dev, \
1492 struct device_attribute *attr, char *buf) \
1494 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1495 return snprintf(buf, PAGE_SIZE, "%s\n", \
1496 usb_speed_string(udc->gadget->param)); \
1498 static DEVICE_ATTR_RO(name)
1500 static USB_UDC_SPEED_ATTR(current_speed, speed);
1501 static USB_UDC_SPEED_ATTR(maximum_speed, max_speed);
1503 #define USB_UDC_ATTR(name) \
1504 ssize_t name##_show(struct device *dev, \
1505 struct device_attribute *attr, char *buf) \
1507 struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \
1508 struct usb_gadget *gadget = udc->gadget; \
1510 return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
1512 static DEVICE_ATTR_RO(name)
1514 static USB_UDC_ATTR(is_otg);
1515 static USB_UDC_ATTR(is_a_peripheral);
1516 static USB_UDC_ATTR(b_hnp_enable);
1517 static USB_UDC_ATTR(a_hnp_support);
1518 static USB_UDC_ATTR(a_alt_hnp_support);
1519 static USB_UDC_ATTR(is_selfpowered);
1521 static struct attribute *usb_udc_attrs[] = {
1523 &dev_attr_soft_connect.attr,
1524 &dev_attr_state.attr,
1525 &dev_attr_function.attr,
1526 &dev_attr_current_speed.attr,
1527 &dev_attr_maximum_speed.attr,
1529 &dev_attr_is_otg.attr,
1530 &dev_attr_is_a_peripheral.attr,
1531 &dev_attr_b_hnp_enable.attr,
1532 &dev_attr_a_hnp_support.attr,
1533 &dev_attr_a_alt_hnp_support.attr,
1534 &dev_attr_is_selfpowered.attr,
1538 static const struct attribute_group usb_udc_attr_group = {
1539 .attrs = usb_udc_attrs,
1542 static const struct attribute_group *usb_udc_attr_groups[] = {
1543 &usb_udc_attr_group,
1547 static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
1549 struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
1552 ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
1554 dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
1559 ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
1560 udc->driver->function);
1562 dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
1570 static int __init usb_udc_init(void)
1572 udc_class = class_create(THIS_MODULE, "udc");
1573 if (IS_ERR(udc_class)) {
1574 pr_err("failed to create udc class --> %ld\n",
1575 PTR_ERR(udc_class));
1576 return PTR_ERR(udc_class);
1579 udc_class->dev_uevent = usb_udc_uevent;
1582 subsys_initcall(usb_udc_init);
1584 static void __exit usb_udc_exit(void)
1586 class_destroy(udc_class);
1588 module_exit(usb_udc_exit);
1590 MODULE_DESCRIPTION("UDC Framework");
1591 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
1592 MODULE_LICENSE("GPL v2");