4 * We call the USB code inside a Linux-based peripheral device a "gadget"
5 * driver, except for the hardware-specific bus glue. One USB host can
6 * master many USB gadgets, but the gadgets are only slaved to one host.
9 * (C) Copyright 2002-2004 by David Brownell
10 * All Rights Reserved.
12 * This software is licensed under the GNU GPL version 2.
15 #ifndef __LINUX_USB_GADGET_H
16 #define __LINUX_USB_GADGET_H
18 #include <linux/device.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/list.h>
22 #include <linux/slab.h>
23 #include <linux/scatterlist.h>
24 #include <linux/types.h>
25 #include <linux/workqueue.h>
26 #include <linux/usb/ch9.h>
31 * struct usb_request - describes one i/o request
32 * @buf: Buffer used for data. Always provide this; some controllers
33 * only use PIO, or don't use DMA for some endpoints.
34 * @dma: DMA address corresponding to 'buf'. If you don't set this
35 * field, and the usb controller needs one, it is responsible
36 * for mapping and unmapping the buffer.
37 * @sg: a scatterlist for SG-capable controllers.
38 * @num_sgs: number of SG entries
39 * @num_mapped_sgs: number of SG entries mapped to DMA (internal)
40 * @length: Length of that data
41 * @stream_id: The stream id, when USB3.0 bulk streams are being used
42 * @no_interrupt: If true, hints that no completion irq is needed.
43 * Helpful sometimes with deep request queues that are handled
44 * directly by DMA controllers.
45 * @zero: If true, when writing data, makes the last packet be "short"
46 * by adding a zero length packet as needed;
47 * @short_not_ok: When reading data, makes short packets be
48 * treated as errors (queue stops advancing till cleanup).
49 * @complete: Function called when request completes, so this request and
50 * its buffer may be re-used. The function will always be called with
51 * interrupts disabled, and it must not sleep.
52 * Reads terminate with a short packet, or when the buffer fills,
53 * whichever comes first. When writes terminate, some data bytes
54 * will usually still be in flight (often in a hardware fifo).
55 * Errors (for reads or writes) stop the queue from advancing
56 * until the completion function returns, so that any transfers
57 * invalidated by the error may first be dequeued.
58 * @context: For use by the completion callback
59 * @list: For use by the gadget driver.
60 * @status: Reports completion code, zero or a negative errno.
61 * Normally, faults block the transfer queue from advancing until
62 * the completion callback returns.
63 * Code "-ESHUTDOWN" indicates completion caused by device disconnect,
64 * or when the driver disabled the endpoint.
65 * @actual: Reports bytes transferred to/from the buffer. For reads (OUT
66 * transfers) this may be less than the requested length. If the
67 * short_not_ok flag is set, short reads are treated as errors
68 * even when status otherwise indicates successful completion.
69 * Note that for writes (IN transfers) some data bytes may still
70 * reside in a device-side FIFO when the request is reported as
73 * These are allocated/freed through the endpoint they're used with. The
74 * hardware's driver can add extra per-request data to the memory it returns,
75 * which often avoids separate memory allocations (potential failures),
76 * later when the request is queued.
78 * Request flags affect request handling, such as whether a zero length
79 * packet is written (the "zero" flag), whether a short read should be
80 * treated as an error (blocking request queue advance, the "short_not_ok"
81 * flag), or hinting that an interrupt is not required (the "no_interrupt"
82 * flag, for use with deep request queues).
84 * Bulk endpoints can use any size buffers, and can also be used for interrupt
85 * transfers. interrupt-only endpoints can be much less functional.
87 * NOTE: this is analogous to 'struct urb' on the host side, except that
88 * it's thinner and promotes more pre-allocation.
96 struct scatterlist *sg;
98 unsigned num_mapped_sgs;
100 unsigned stream_id:16;
101 unsigned no_interrupt:1;
103 unsigned short_not_ok:1;
105 void (*complete)(struct usb_ep *ep,
106 struct usb_request *req);
108 struct list_head list;
114 /*-------------------------------------------------------------------------*/
116 /* endpoint-specific parts of the api to the usb controller hardware.
117 * unlike the urb model, (de)multiplexing layers are not required.
118 * (so this api could slash overhead if used on the host side...)
120 * note that device side usb controllers commonly differ in how many
121 * endpoints they support, as well as their capabilities.
124 int (*enable) (struct usb_ep *ep,
125 const struct usb_endpoint_descriptor *desc);
126 int (*disable) (struct usb_ep *ep);
128 struct usb_request *(*alloc_request) (struct usb_ep *ep,
130 void (*free_request) (struct usb_ep *ep, struct usb_request *req);
132 int (*queue) (struct usb_ep *ep, struct usb_request *req,
134 int (*dequeue) (struct usb_ep *ep, struct usb_request *req);
136 int (*set_halt) (struct usb_ep *ep, int value);
137 int (*set_wedge) (struct usb_ep *ep);
139 int (*fifo_status) (struct usb_ep *ep);
140 void (*fifo_flush) (struct usb_ep *ep);
144 * struct usb_ep_caps - endpoint capabilities description
145 * @type_control:Endpoint supports control type (reserved for ep0).
146 * @type_iso:Endpoint supports isochronous transfers.
147 * @type_bulk:Endpoint supports bulk transfers.
148 * @type_int:Endpoint supports interrupt transfers.
149 * @dir_in:Endpoint supports IN direction.
150 * @dir_out:Endpoint supports OUT direction.
153 unsigned type_control:1;
155 unsigned type_bulk:1;
161 #define USB_EP_CAPS_TYPE_CONTROL 0x01
162 #define USB_EP_CAPS_TYPE_ISO 0x02
163 #define USB_EP_CAPS_TYPE_BULK 0x04
164 #define USB_EP_CAPS_TYPE_INT 0x08
165 #define USB_EP_CAPS_TYPE_ALL \
166 (USB_EP_CAPS_TYPE_ISO | USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT)
167 #define USB_EP_CAPS_DIR_IN 0x01
168 #define USB_EP_CAPS_DIR_OUT 0x02
169 #define USB_EP_CAPS_DIR_ALL (USB_EP_CAPS_DIR_IN | USB_EP_CAPS_DIR_OUT)
171 #define USB_EP_CAPS(_type, _dir) \
173 .type_control = !!(_type & USB_EP_CAPS_TYPE_CONTROL), \
174 .type_iso = !!(_type & USB_EP_CAPS_TYPE_ISO), \
175 .type_bulk = !!(_type & USB_EP_CAPS_TYPE_BULK), \
176 .type_int = !!(_type & USB_EP_CAPS_TYPE_INT), \
177 .dir_in = !!(_dir & USB_EP_CAPS_DIR_IN), \
178 .dir_out = !!(_dir & USB_EP_CAPS_DIR_OUT), \
182 * struct usb_ep - device side representation of USB endpoint
183 * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk"
184 * @ops: Function pointers used to access hardware-specific operations.
185 * @ep_list:the gadget's ep_list holds all of its endpoints
186 * @caps:The structure describing types and directions supported by endoint.
187 * @maxpacket:The maximum packet size used on this endpoint. The initial
188 * value can sometimes be reduced (hardware allowing), according to
189 * the endpoint descriptor used to configure the endpoint.
190 * @maxpacket_limit:The maximum packet size value which can be handled by this
191 * endpoint. It's set once by UDC driver when endpoint is initialized, and
192 * should not be changed. Should not be confused with maxpacket.
193 * @max_streams: The maximum number of streams supported
194 * by this EP (0 - 16, actual number is 2^n)
195 * @mult: multiplier, 'mult' value for SS Isoc EPs
196 * @maxburst: the maximum number of bursts supported by this EP (for usb3)
197 * @driver_data:for use by the gadget driver.
198 * @address: used to identify the endpoint when finding descriptor that
199 * matches connection speed
200 * @desc: endpoint descriptor. This pointer is set before the endpoint is
201 * enabled and remains valid until the endpoint is disabled.
202 * @comp_desc: In case of SuperSpeed support, this is the endpoint companion
203 * descriptor that is used to configure the endpoint
205 * the bus controller driver lists all the general purpose endpoints in
206 * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list,
207 * and is accessed only in response to a driver setup() callback.
214 const struct usb_ep_ops *ops;
215 struct list_head ep_list;
216 struct usb_ep_caps caps;
219 unsigned maxpacket:16;
220 unsigned maxpacket_limit:16;
221 unsigned max_streams:16;
225 const struct usb_endpoint_descriptor *desc;
226 const struct usb_ss_ep_comp_descriptor *comp_desc;
229 /*-------------------------------------------------------------------------*/
232 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint
233 * @ep:the endpoint being configured
234 * @maxpacket_limit:value of maximum packet size limit
236 * This function should be used only in UDC drivers to initialize endpoint
237 * (usually in probe function).
239 static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
240 unsigned maxpacket_limit)
242 ep->maxpacket_limit = maxpacket_limit;
243 ep->maxpacket = maxpacket_limit;
247 * usb_ep_enable - configure endpoint, making it usable
248 * @ep:the endpoint being configured. may not be the endpoint named "ep0".
249 * drivers discover endpoints through the ep_list of a usb_gadget.
251 * When configurations are set, or when interface settings change, the driver
252 * will enable or disable the relevant endpoints. while it is enabled, an
253 * endpoint may be used for i/o until the driver receives a disconnect() from
254 * the host or until the endpoint is disabled.
256 * the ep0 implementation (which calls this routine) must ensure that the
257 * hardware capabilities of each endpoint match the descriptor provided
258 * for it. for example, an endpoint named "ep2in-bulk" would be usable
259 * for interrupt transfers as well as bulk, but it likely couldn't be used
260 * for iso transfers or for endpoint 14. some endpoints are fully
261 * configurable, with more generic names like "ep-a". (remember that for
262 * USB, "in" means "towards the USB master".)
264 * returns zero, or a negative error code.
266 static inline int usb_ep_enable(struct usb_ep *ep)
273 /* UDC drivers can't handle endpoints with maxpacket size 0 */
274 if (usb_endpoint_maxp(ep->desc) == 0) {
276 * We should log an error message here, but we can't call
277 * dev_err() because there's no way to find the gadget
283 ret = ep->ops->enable(ep, ep->desc);
293 * usb_ep_disable - endpoint is no longer usable
294 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
296 * no other task may be using this endpoint when this is called.
297 * any pending and uncompleted requests will complete with status
298 * indicating disconnect (-ESHUTDOWN) before this call returns.
299 * gadget drivers must call usb_ep_enable() again before queueing
300 * requests to the endpoint.
302 * returns zero, or a negative error code.
304 static inline int usb_ep_disable(struct usb_ep *ep)
311 ret = ep->ops->disable(ep);
321 * usb_ep_alloc_request - allocate a request object to use with this endpoint
322 * @ep:the endpoint to be used with with the request
323 * @gfp_flags:GFP_* flags to use
325 * Request objects must be allocated with this call, since they normally
326 * need controller-specific setup and may even need endpoint-specific
327 * resources such as allocation of DMA descriptors.
328 * Requests may be submitted with usb_ep_queue(), and receive a single
329 * completion callback. Free requests with usb_ep_free_request(), when
330 * they are no longer needed.
332 * Returns the request, or null if one could not be allocated.
334 static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
337 return ep->ops->alloc_request(ep, gfp_flags);
341 * usb_ep_free_request - frees a request object
342 * @ep:the endpoint associated with the request
343 * @req:the request being freed
345 * Reverses the effect of usb_ep_alloc_request().
346 * Caller guarantees the request is not queued, and that it will
347 * no longer be requeued (or otherwise used).
349 static inline void usb_ep_free_request(struct usb_ep *ep,
350 struct usb_request *req)
352 ep->ops->free_request(ep, req);
356 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
357 * @ep:the endpoint associated with the request
358 * @req:the request being submitted
359 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
360 * pre-allocate all necessary memory with the request.
362 * This tells the device controller to perform the specified request through
363 * that endpoint (reading or writing a buffer). When the request completes,
364 * including being canceled by usb_ep_dequeue(), the request's completion
365 * routine is called to return the request to the driver. Any endpoint
366 * (except control endpoints like ep0) may have more than one transfer
367 * request queued; they complete in FIFO order. Once a gadget driver
368 * submits a request, that request may not be examined or modified until it
369 * is given back to that driver through the completion callback.
371 * Each request is turned into one or more packets. The controller driver
372 * never merges adjacent requests into the same packet. OUT transfers
373 * will sometimes use data that's already buffered in the hardware.
374 * Drivers can rely on the fact that the first byte of the request's buffer
375 * always corresponds to the first byte of some USB packet, for both
376 * IN and OUT transfers.
378 * Bulk endpoints can queue any amount of data; the transfer is packetized
379 * automatically. The last packet will be short if the request doesn't fill it
380 * out completely. Zero length packets (ZLPs) should be avoided in portable
381 * protocols since not all usb hardware can successfully handle zero length
382 * packets. (ZLPs may be explicitly written, and may be implicitly written if
383 * the request 'zero' flag is set.) Bulk endpoints may also be used
384 * for interrupt transfers; but the reverse is not true, and some endpoints
385 * won't support every interrupt transfer. (Such as 768 byte packets.)
387 * Interrupt-only endpoints are less functional than bulk endpoints, for
388 * example by not supporting queueing or not handling buffers that are
389 * larger than the endpoint's maxpacket size. They may also treat data
390 * toggle differently.
392 * Control endpoints ... after getting a setup() callback, the driver queues
393 * one response (even if it would be zero length). That enables the
394 * status ack, after transferring data as specified in the response. Setup
395 * functions may return negative error codes to generate protocol stalls.
396 * (Note that some USB device controllers disallow protocol stall responses
397 * in some cases.) When control responses are deferred (the response is
398 * written after the setup callback returns), then usb_ep_set_halt() may be
399 * used on ep0 to trigger protocol stalls. Depending on the controller,
400 * it may not be possible to trigger a status-stage protocol stall when the
401 * data stage is over, that is, from within the response's completion
404 * For periodic endpoints, like interrupt or isochronous ones, the usb host
405 * arranges to poll once per interval, and the gadget driver usually will
406 * have queued some data to transfer at that time.
408 * Returns zero, or a negative error code. Endpoints that are not enabled
409 * report errors; errors will also be
410 * reported when the usb peripheral is disconnected.
412 static inline int usb_ep_queue(struct usb_ep *ep,
413 struct usb_request *req, gfp_t gfp_flags)
415 return ep->ops->queue(ep, req, gfp_flags);
419 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
420 * @ep:the endpoint associated with the request
421 * @req:the request being canceled
423 * If the request is still active on the endpoint, it is dequeued and its
424 * completion routine is called (with status -ECONNRESET); else a negative
425 * error code is returned. This is guaranteed to happen before the call to
426 * usb_ep_dequeue() returns.
428 * Note that some hardware can't clear out write fifos (to unlink the request
429 * at the head of the queue) except as part of disconnecting from usb. Such
430 * restrictions prevent drivers from supporting configuration changes,
431 * even to configuration zero (a "chapter 9" requirement).
433 static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
435 return ep->ops->dequeue(ep, req);
439 * usb_ep_set_halt - sets the endpoint halt feature.
440 * @ep: the non-isochronous endpoint being stalled
442 * Use this to stall an endpoint, perhaps as an error report.
443 * Except for control endpoints,
444 * the endpoint stays halted (will not stream any data) until the host
445 * clears this feature; drivers may need to empty the endpoint's request
446 * queue first, to make sure no inappropriate transfers happen.
448 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
449 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
450 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
451 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
453 * Returns zero, or a negative error code. On success, this call sets
454 * underlying hardware state that blocks data transfers.
455 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
456 * transfer requests are still queued, or if the controller hardware
457 * (usually a FIFO) still holds bytes that the host hasn't collected.
459 static inline int usb_ep_set_halt(struct usb_ep *ep)
461 return ep->ops->set_halt(ep, 1);
465 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
466 * @ep:the bulk or interrupt endpoint being reset
468 * Use this when responding to the standard usb "set interface" request,
469 * for endpoints that aren't reconfigured, after clearing any other state
470 * in the endpoint's i/o queue.
472 * Returns zero, or a negative error code. On success, this call clears
473 * the underlying hardware state reflecting endpoint halt and data toggle.
474 * Note that some hardware can't support this request (like pxa2xx_udc),
475 * and accordingly can't correctly implement interface altsettings.
477 static inline int usb_ep_clear_halt(struct usb_ep *ep)
479 return ep->ops->set_halt(ep, 0);
483 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
484 * @ep: the endpoint being wedged
486 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
487 * requests. If the gadget driver clears the halt status, it will
488 * automatically unwedge the endpoint.
490 * Returns zero on success, else negative errno.
493 usb_ep_set_wedge(struct usb_ep *ep)
495 if (ep->ops->set_wedge)
496 return ep->ops->set_wedge(ep);
498 return ep->ops->set_halt(ep, 1);
502 * usb_ep_fifo_status - returns number of bytes in fifo, or error
503 * @ep: the endpoint whose fifo status is being checked.
505 * FIFO endpoints may have "unclaimed data" in them in certain cases,
506 * such as after aborted transfers. Hosts may not have collected all
507 * the IN data written by the gadget driver (and reported by a request
508 * completion). The gadget driver may not have collected all the data
509 * written OUT to it by the host. Drivers that need precise handling for
510 * fault reporting or recovery may need to use this call.
512 * This returns the number of such bytes in the fifo, or a negative
513 * errno if the endpoint doesn't use a FIFO or doesn't support such
516 static inline int usb_ep_fifo_status(struct usb_ep *ep)
518 if (ep->ops->fifo_status)
519 return ep->ops->fifo_status(ep);
525 * usb_ep_fifo_flush - flushes contents of a fifo
526 * @ep: the endpoint whose fifo is being flushed.
528 * This call may be used to flush the "unclaimed data" that may exist in
529 * an endpoint fifo after abnormal transaction terminations. The call
530 * must never be used except when endpoint is not being used for any
531 * protocol translation.
533 static inline void usb_ep_fifo_flush(struct usb_ep *ep)
535 if (ep->ops->fifo_flush)
536 ep->ops->fifo_flush(ep);
540 /*-------------------------------------------------------------------------*/
542 struct usb_dcd_config_params {
543 __u8 bU1devExitLat; /* U1 Device exit Latency */
544 #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */
545 __le16 bU2DevExitLat; /* U2 Device exit Latency */
546 #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */
551 struct usb_gadget_driver;
554 /* the rest of the api to the controller hardware: device operations,
555 * which don't involve endpoints (or i/o).
557 struct usb_gadget_ops {
558 int (*get_frame)(struct usb_gadget *);
559 int (*wakeup)(struct usb_gadget *);
560 int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered);
561 int (*vbus_session) (struct usb_gadget *, int is_active);
562 int (*vbus_draw) (struct usb_gadget *, unsigned mA);
563 int (*pullup) (struct usb_gadget *, int is_on);
564 int (*ioctl)(struct usb_gadget *,
565 unsigned code, unsigned long param);
566 void (*get_config_params)(struct usb_dcd_config_params *);
567 int (*udc_start)(struct usb_gadget *,
568 struct usb_gadget_driver *);
569 int (*udc_stop)(struct usb_gadget *);
570 struct usb_ep *(*match_ep)(struct usb_gadget *,
571 struct usb_endpoint_descriptor *,
572 struct usb_ss_ep_comp_descriptor *);
576 * struct usb_gadget - represents a usb slave device
577 * @work: (internal use) Workqueue to be used for sysfs_notify()
578 * @udc: struct usb_udc pointer for this gadget
579 * @ops: Function pointers used to access hardware-specific operations.
580 * @ep0: Endpoint zero, used when reading or writing responses to
581 * driver setup() requests
582 * @ep_list: List of other endpoints supported by the device.
583 * @speed: Speed of current connection to USB host.
584 * @max_speed: Maximal speed the UDC can handle. UDC must support this
585 * and all slower speeds.
586 * @state: the state we are now (attached, suspended, configured, etc)
587 * @name: Identifies the controller hardware type. Used in diagnostics
588 * and sometimes configuration.
589 * @dev: Driver model state for this abstract device.
590 * @out_epnum: last used out ep number
591 * @in_epnum: last used in ep number
592 * @otg_caps: OTG capabilities of this gadget.
593 * @sg_supported: true if we can handle scatter-gather
594 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the
595 * gadget driver must provide a USB OTG descriptor.
596 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable
597 * is in the Mini-AB jack, and HNP has been used to switch roles
598 * so that the "A" device currently acts as A-Peripheral, not A-Host.
599 * @a_hnp_support: OTG device feature flag, indicating that the A-Host
600 * supports HNP at this port.
601 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host
602 * only supports HNP on a different root port.
603 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host
604 * enabled HNP support.
605 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to
607 * @is_selfpowered: if the gadget is self-powered.
608 * @deactivated: True if gadget is deactivated - in deactivated state it cannot
610 * @connected: True if gadget is connected.
612 * Gadgets have a mostly-portable "gadget driver" implementing device
613 * functions, handling all usb configurations and interfaces. Gadget
614 * drivers talk to hardware-specific code indirectly, through ops vectors.
615 * That insulates the gadget driver from hardware details, and packages
616 * the hardware endpoints through generic i/o queues. The "usb_gadget"
617 * and "usb_ep" interfaces provide that insulation from the hardware.
619 * Except for the driver data, all fields in this structure are
620 * read-only to the gadget driver. That driver data is part of the
621 * "driver model" infrastructure in 2.6 (and later) kernels, and for
622 * earlier systems is grouped in a similar structure that's not known
623 * to the rest of the kernel.
625 * Values of the three OTG device feature flags are updated before the
626 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before
627 * driver suspend() calls. They are valid only when is_otg, and when the
628 * device is acting as a B-Peripheral (so is_a_peripheral is false).
631 struct work_struct work;
633 /* readonly to gadget driver */
634 const struct usb_gadget_ops *ops;
636 struct list_head ep_list; /* of usb_ep */
637 enum usb_device_speed speed;
638 enum usb_device_speed max_speed;
639 enum usb_device_state state;
644 struct usb_otg_caps *otg_caps;
646 unsigned sg_supported:1;
648 unsigned is_a_peripheral:1;
649 unsigned b_hnp_enable:1;
650 unsigned a_hnp_support:1;
651 unsigned a_alt_hnp_support:1;
652 unsigned quirk_ep_out_aligned_size:1;
653 unsigned quirk_altset_not_supp:1;
654 unsigned quirk_stall_not_supp:1;
655 unsigned quirk_zlp_not_supp:1;
656 unsigned is_selfpowered:1;
657 unsigned deactivated:1;
658 unsigned connected:1;
660 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work))
662 static inline void set_gadget_data(struct usb_gadget *gadget, void *data)
663 { dev_set_drvdata(&gadget->dev, data); }
664 static inline void *get_gadget_data(struct usb_gadget *gadget)
665 { return dev_get_drvdata(&gadget->dev); }
666 static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev)
668 return container_of(dev, struct usb_gadget, dev);
671 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */
672 #define gadget_for_each_ep(tmp, gadget) \
673 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list)
676 * usb_ep_align - returns @len aligned to ep's maxpacketsize.
677 * @ep: the endpoint whose maxpacketsize is used to align @len
678 * @len: buffer size's length to align to @ep's maxpacketsize
680 * This helper is used to align buffer's size to an ep's maxpacketsize.
682 static inline size_t usb_ep_align(struct usb_ep *ep, size_t len)
684 int max_packet_size = (size_t)usb_endpoint_maxp(ep->desc) & 0x7ff;
686 return round_up(len, max_packet_size);
690 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget
691 * requires quirk_ep_out_aligned_size, otherwise returns len.
692 * @g: controller to check for quirk
693 * @ep: the endpoint whose maxpacketsize is used to align @len
694 * @len: buffer size's length to align to @ep's maxpacketsize
696 * This helper is used in case it's required for any reason to check and maybe
697 * align buffer's size to an ep's maxpacketsize.
700 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len)
702 return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len;
706 * gadget_is_altset_supported - return true iff the hardware supports
708 * @g: controller to check for quirk
710 static inline int gadget_is_altset_supported(struct usb_gadget *g)
712 return !g->quirk_altset_not_supp;
716 * gadget_is_stall_supported - return true iff the hardware supports stalling
717 * @g: controller to check for quirk
719 static inline int gadget_is_stall_supported(struct usb_gadget *g)
721 return !g->quirk_stall_not_supp;
725 * gadget_is_zlp_supported - return true iff the hardware supports zlp
726 * @g: controller to check for quirk
728 static inline int gadget_is_zlp_supported(struct usb_gadget *g)
730 return !g->quirk_zlp_not_supp;
734 * gadget_is_dualspeed - return true iff the hardware handles high speed
735 * @g: controller that might support both high and full speeds
737 static inline int gadget_is_dualspeed(struct usb_gadget *g)
739 return g->max_speed >= USB_SPEED_HIGH;
743 * gadget_is_superspeed() - return true if the hardware handles superspeed
744 * @g: controller that might support superspeed
746 static inline int gadget_is_superspeed(struct usb_gadget *g)
748 return g->max_speed >= USB_SPEED_SUPER;
752 * gadget_is_otg - return true iff the hardware is OTG-ready
753 * @g: controller that might have a Mini-AB connector
755 * This is a runtime test, since kernels with a USB-OTG stack sometimes
756 * run on boards which only have a Mini-B (or Mini-A) connector.
758 static inline int gadget_is_otg(struct usb_gadget *g)
760 #ifdef CONFIG_USB_OTG
768 * usb_gadget_frame_number - returns the current frame number
769 * @gadget: controller that reports the frame number
771 * Returns the usb frame number, normally eleven bits from a SOF packet,
772 * or negative errno if this device doesn't support this capability.
774 static inline int usb_gadget_frame_number(struct usb_gadget *gadget)
776 return gadget->ops->get_frame(gadget);
780 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
781 * @gadget: controller used to wake up the host
783 * Returns zero on success, else negative error code if the hardware
784 * doesn't support such attempts, or its support has not been enabled
785 * by the usb host. Drivers must return device descriptors that report
786 * their ability to support this, or hosts won't enable it.
788 * This may also try to use SRP to wake the host and start enumeration,
789 * even if OTG isn't otherwise in use. OTG devices may also start
790 * remote wakeup even when hosts don't explicitly enable it.
792 static inline int usb_gadget_wakeup(struct usb_gadget *gadget)
794 if (!gadget->ops->wakeup)
796 return gadget->ops->wakeup(gadget);
800 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
801 * @gadget:the device being declared as self-powered
803 * this affects the device status reported by the hardware driver
804 * to reflect that it now has a local power supply.
806 * returns zero on success, else negative errno.
808 static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget)
810 if (!gadget->ops->set_selfpowered)
812 return gadget->ops->set_selfpowered(gadget, 1);
816 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
817 * @gadget:the device being declared as bus-powered
819 * this affects the device status reported by the hardware driver.
820 * some hardware may not support bus-powered operation, in which
821 * case this feature's value can never change.
823 * returns zero on success, else negative errno.
825 static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget)
827 if (!gadget->ops->set_selfpowered)
829 return gadget->ops->set_selfpowered(gadget, 0);
833 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
834 * @gadget:The device which now has VBUS power.
837 * This call is used by a driver for an external transceiver (or GPIO)
838 * that detects a VBUS power session starting. Common responses include
839 * resuming the controller, activating the D+ (or D-) pullup to let the
840 * host detect that a USB device is attached, and starting to draw power
841 * (8mA or possibly more, especially after SET_CONFIGURATION).
843 * Returns zero on success, else negative errno.
845 static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget)
847 if (!gadget->ops->vbus_session)
849 return gadget->ops->vbus_session(gadget, 1);
853 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
854 * @gadget:The device whose VBUS usage is being described
855 * @mA:How much current to draw, in milliAmperes. This should be twice
856 * the value listed in the configuration descriptor bMaxPower field.
858 * This call is used by gadget drivers during SET_CONFIGURATION calls,
859 * reporting how much power the device may consume. For example, this
860 * could affect how quickly batteries are recharged.
862 * Returns zero on success, else negative errno.
864 static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
866 if (!gadget->ops->vbus_draw)
868 return gadget->ops->vbus_draw(gadget, mA);
872 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
873 * @gadget:the device whose VBUS supply is being described
876 * This call is used by a driver for an external transceiver (or GPIO)
877 * that detects a VBUS power session ending. Common responses include
878 * reversing everything done in usb_gadget_vbus_connect().
880 * Returns zero on success, else negative errno.
882 static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
884 if (!gadget->ops->vbus_session)
886 return gadget->ops->vbus_session(gadget, 0);
890 * usb_gadget_connect - software-controlled connect to USB host
891 * @gadget:the peripheral being connected
893 * Enables the D+ (or potentially D-) pullup. The host will start
894 * enumerating this gadget when the pullup is active and a VBUS session
895 * is active (the link is powered). This pullup is always enabled unless
896 * usb_gadget_disconnect() has been used to disable it.
898 * Returns zero on success, else negative errno.
900 static inline int usb_gadget_connect(struct usb_gadget *gadget)
904 if (!gadget->ops->pullup)
907 if (gadget->deactivated) {
909 * If gadget is deactivated we only save new state.
910 * Gadget will be connected automatically after activation.
912 gadget->connected = true;
916 ret = gadget->ops->pullup(gadget, 1);
918 gadget->connected = 1;
923 * usb_gadget_disconnect - software-controlled disconnect from USB host
924 * @gadget:the peripheral being disconnected
926 * Disables the D+ (or potentially D-) pullup, which the host may see
927 * as a disconnect (when a VBUS session is active). Not all systems
928 * support software pullup controls.
930 * Returns zero on success, else negative errno.
932 static inline int usb_gadget_disconnect(struct usb_gadget *gadget)
936 if (!gadget->ops->pullup)
939 if (gadget->deactivated) {
941 * If gadget is deactivated we only save new state.
942 * Gadget will stay disconnected after activation.
944 gadget->connected = false;
948 ret = gadget->ops->pullup(gadget, 0);
950 gadget->connected = 0;
955 * usb_gadget_deactivate - deactivate function which is not ready to work
956 * @gadget: the peripheral being deactivated
958 * This routine may be used during the gadget driver bind() call to prevent
959 * the peripheral from ever being visible to the USB host, unless later
960 * usb_gadget_activate() is called. For example, user mode components may
961 * need to be activated before the system can talk to hosts.
963 * Returns zero on success, else negative errno.
965 static inline int usb_gadget_deactivate(struct usb_gadget *gadget)
969 if (gadget->deactivated)
972 if (gadget->connected) {
973 ret = usb_gadget_disconnect(gadget);
977 * If gadget was being connected before deactivation, we want
978 * to reconnect it in usb_gadget_activate().
980 gadget->connected = true;
982 gadget->deactivated = true;
988 * usb_gadget_activate - activate function which is not ready to work
989 * @gadget: the peripheral being activated
991 * This routine activates gadget which was previously deactivated with
992 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
994 * Returns zero on success, else negative errno.
996 static inline int usb_gadget_activate(struct usb_gadget *gadget)
998 if (!gadget->deactivated)
1001 gadget->deactivated = false;
1004 * If gadget has been connected before deactivation, or became connected
1005 * while it was being deactivated, we call usb_gadget_connect().
1007 if (gadget->connected)
1008 return usb_gadget_connect(gadget);
1013 /*-------------------------------------------------------------------------*/
1016 * struct usb_gadget_driver - driver for usb 'slave' devices
1017 * @function: String describing the gadget's function
1018 * @max_speed: Highest speed the driver handles.
1019 * @setup: Invoked for ep0 control requests that aren't handled by
1020 * the hardware level driver. Most calls must be handled by
1021 * the gadget driver, including descriptor and configuration
1022 * management. The 16 bit members of the setup data are in
1023 * USB byte order. Called in_interrupt; this may not sleep. Driver
1024 * queues a response to ep0, or returns negative to stall.
1025 * @disconnect: Invoked after all transfers have been stopped,
1026 * when the host is disconnected. May be called in_interrupt; this
1027 * may not sleep. Some devices can't detect disconnect, so this might
1028 * not be called except as part of controller shutdown.
1029 * @bind: the driver's bind callback
1030 * @unbind: Invoked when the driver is unbound from a gadget,
1031 * usually from rmmod (after a disconnect is reported).
1032 * Called in a context that permits sleeping.
1033 * @suspend: Invoked on USB suspend. May be called in_interrupt.
1034 * @resume: Invoked on USB resume. May be called in_interrupt.
1035 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers
1036 * and should be called in_interrupt.
1037 * @driver: Driver model state for this driver.
1039 * Devices are disabled till a gadget driver successfully bind()s, which
1040 * means the driver will handle setup() requests needed to enumerate (and
1041 * meet "chapter 9" requirements) then do some useful work.
1043 * If gadget->is_otg is true, the gadget driver must provide an OTG
1044 * descriptor during enumeration, or else fail the bind() call. In such
1045 * cases, no USB traffic may flow until both bind() returns without
1046 * having called usb_gadget_disconnect(), and the USB host stack has
1049 * Drivers use hardware-specific knowledge to configure the usb hardware.
1050 * endpoint addressing is only one of several hardware characteristics that
1051 * are in descriptors the ep0 implementation returns from setup() calls.
1053 * Except for ep0 implementation, most driver code shouldn't need change to
1054 * run on top of different usb controllers. It'll use endpoints set up by
1055 * that ep0 implementation.
1057 * The usb controller driver handles a few standard usb requests. Those
1058 * include set_address, and feature flags for devices, interfaces, and
1059 * endpoints (the get_status, set_feature, and clear_feature requests).
1061 * Accordingly, the driver's setup() callback must always implement all
1062 * get_descriptor requests, returning at least a device descriptor and
1063 * a configuration descriptor. Drivers must make sure the endpoint
1064 * descriptors match any hardware constraints. Some hardware also constrains
1065 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3).
1067 * The driver's setup() callback must also implement set_configuration,
1068 * and should also implement set_interface, get_configuration, and
1069 * get_interface. Setting a configuration (or interface) is where
1070 * endpoints should be activated or (config 0) shut down.
1072 * (Note that only the default control endpoint is supported. Neither
1073 * hosts nor devices generally support control traffic except to ep0.)
1075 * Most devices will ignore USB suspend/resume operations, and so will
1076 * not provide those callbacks. However, some may need to change modes
1077 * when the host is not longer directing those activities. For example,
1078 * local controls (buttons, dials, etc) may need to be re-enabled since
1079 * the (remote) host can't do that any longer; or an error state might
1080 * be cleared, to make the device behave identically whether or not
1081 * power is maintained.
1083 struct usb_gadget_driver {
1085 enum usb_device_speed max_speed;
1086 int (*bind)(struct usb_gadget *gadget,
1087 struct usb_gadget_driver *driver);
1088 void (*unbind)(struct usb_gadget *);
1089 int (*setup)(struct usb_gadget *,
1090 const struct usb_ctrlrequest *);
1091 void (*disconnect)(struct usb_gadget *);
1092 void (*suspend)(struct usb_gadget *);
1093 void (*resume)(struct usb_gadget *);
1094 void (*reset)(struct usb_gadget *);
1096 /* FIXME support safe rmmod */
1097 struct device_driver driver;
1102 /*-------------------------------------------------------------------------*/
1104 /* driver modules register and unregister, as usual.
1105 * these calls must be made in a context that can sleep.
1107 * these will usually be implemented directly by the hardware-dependent
1108 * usb bus interface driver, which will only support a single driver.
1112 * usb_gadget_probe_driver - probe a gadget driver
1113 * @driver: the driver being registered
1114 * Context: can sleep
1116 * Call this in your gadget driver's module initialization function,
1117 * to tell the underlying usb controller driver about your driver.
1118 * The @bind() function will be called to bind it to a gadget before this
1119 * registration call returns. It's expected that the @bind() function will
1120 * be in init sections.
1122 int usb_gadget_probe_driver(struct usb_gadget_driver *driver);
1125 * usb_gadget_unregister_driver - unregister a gadget driver
1126 * @driver:the driver being unregistered
1127 * Context: can sleep
1129 * Call this in your gadget driver's module cleanup function,
1130 * to tell the underlying usb controller that your driver is
1131 * going away. If the controller is connected to a USB host,
1132 * it will first disconnect(). The driver is also requested
1133 * to unbind() and clean up any device state, before this procedure
1134 * finally returns. It's expected that the unbind() functions
1135 * will in in exit sections, so may not be linked in some kernels.
1137 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver);
1139 extern int usb_add_gadget_udc_release(struct device *parent,
1140 struct usb_gadget *gadget, void (*release)(struct device *dev));
1141 extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget);
1142 extern void usb_del_gadget_udc(struct usb_gadget *gadget);
1143 extern int usb_udc_attach_driver(const char *name,
1144 struct usb_gadget_driver *driver);
1146 /*-------------------------------------------------------------------------*/
1148 /* utility to simplify dealing with string descriptors */
1151 * struct usb_string - wraps a C string and its USB id
1152 * @id:the (nonzero) ID for this string
1153 * @s:the string, in UTF-8 encoding
1155 * If you're using usb_gadget_get_string(), use this to wrap a string
1156 * together with its ID.
1164 * struct usb_gadget_strings - a set of USB strings in a given language
1165 * @language:identifies the strings' language (0x0409 for en-us)
1166 * @strings:array of strings with their ids
1168 * If you're using usb_gadget_get_string(), use this to wrap all the
1169 * strings for a given language.
1171 struct usb_gadget_strings {
1172 u16 language; /* 0x0409 for en-us */
1173 struct usb_string *strings;
1176 struct usb_gadget_string_container {
1177 struct list_head list;
1181 /* put descriptor for string with that id into buf (buflen >= 256) */
1182 int usb_gadget_get_string(struct usb_gadget_strings *table, int id, u8 *buf);
1184 /*-------------------------------------------------------------------------*/
1186 /* utility to simplify managing config descriptors */
1188 /* write vector of descriptors into buffer */
1189 int usb_descriptor_fillbuf(void *, unsigned,
1190 const struct usb_descriptor_header **);
1192 /* build config descriptor from single descriptor vector */
1193 int usb_gadget_config_buf(const struct usb_config_descriptor *config,
1194 void *buf, unsigned buflen, const struct usb_descriptor_header **desc);
1196 /* copy a NULL-terminated vector of descriptors */
1197 struct usb_descriptor_header **usb_copy_descriptors(
1198 struct usb_descriptor_header **);
1201 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors()
1202 * @v: vector of descriptors
1204 static inline void usb_free_descriptors(struct usb_descriptor_header **v)
1209 struct usb_function;
1210 int usb_assign_descriptors(struct usb_function *f,
1211 struct usb_descriptor_header **fs,
1212 struct usb_descriptor_header **hs,
1213 struct usb_descriptor_header **ss);
1214 void usb_free_all_descriptors(struct usb_function *f);
1216 struct usb_descriptor_header *usb_otg_descriptor_alloc(
1217 struct usb_gadget *gadget);
1218 int usb_otg_descriptor_init(struct usb_gadget *gadget,
1219 struct usb_descriptor_header *otg_desc);
1220 /*-------------------------------------------------------------------------*/
1222 /* utility to simplify map/unmap of usb_requests to/from DMA */
1224 extern int usb_gadget_map_request(struct usb_gadget *gadget,
1225 struct usb_request *req, int is_in);
1227 extern void usb_gadget_unmap_request(struct usb_gadget *gadget,
1228 struct usb_request *req, int is_in);
1230 /*-------------------------------------------------------------------------*/
1232 /* utility to set gadget state properly */
1234 extern void usb_gadget_set_state(struct usb_gadget *gadget,
1235 enum usb_device_state state);
1237 /*-------------------------------------------------------------------------*/
1239 /* utility to tell udc core that the bus reset occurs */
1240 extern void usb_gadget_udc_reset(struct usb_gadget *gadget,
1241 struct usb_gadget_driver *driver);
1243 /*-------------------------------------------------------------------------*/
1245 /* utility to give requests back to the gadget layer */
1247 extern void usb_gadget_giveback_request(struct usb_ep *ep,
1248 struct usb_request *req);
1250 /*-------------------------------------------------------------------------*/
1252 /* utility to find endpoint by name */
1254 extern struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g,
1257 /*-------------------------------------------------------------------------*/
1259 /* utility to check if endpoint caps match descriptor needs */
1261 extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
1262 struct usb_ep *ep, struct usb_endpoint_descriptor *desc,
1263 struct usb_ss_ep_comp_descriptor *ep_comp);
1265 /*-------------------------------------------------------------------------*/
1267 /* utility to update vbus status for udc core, it may be scheduled */
1268 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status);
1270 /*-------------------------------------------------------------------------*/
1272 /* utility wrapping a simple endpoint selection policy */
1274 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *,
1275 struct usb_endpoint_descriptor *);
1278 extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *,
1279 struct usb_endpoint_descriptor *,
1280 struct usb_ss_ep_comp_descriptor *);
1282 extern void usb_ep_autoconfig_release(struct usb_ep *);
1284 extern void usb_ep_autoconfig_reset(struct usb_gadget *);
1286 #endif /* __LINUX_USB_GADGET_H */