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 ret
= ep
->ops
->enable(ep
, ep
->desc
);
283 * usb_ep_disable - endpoint is no longer usable
284 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0".
286 * no other task may be using this endpoint when this is called.
287 * any pending and uncompleted requests will complete with status
288 * indicating disconnect (-ESHUTDOWN) before this call returns.
289 * gadget drivers must call usb_ep_enable() again before queueing
290 * requests to the endpoint.
292 * returns zero, or a negative error code.
294 static inline int usb_ep_disable(struct usb_ep
*ep
)
301 ret
= ep
->ops
->disable(ep
);
311 * usb_ep_alloc_request - allocate a request object to use with this endpoint
312 * @ep:the endpoint to be used with with the request
313 * @gfp_flags:GFP_* flags to use
315 * Request objects must be allocated with this call, since they normally
316 * need controller-specific setup and may even need endpoint-specific
317 * resources such as allocation of DMA descriptors.
318 * Requests may be submitted with usb_ep_queue(), and receive a single
319 * completion callback. Free requests with usb_ep_free_request(), when
320 * they are no longer needed.
322 * Returns the request, or null if one could not be allocated.
324 static inline struct usb_request
*usb_ep_alloc_request(struct usb_ep
*ep
,
327 return ep
->ops
->alloc_request(ep
, gfp_flags
);
331 * usb_ep_free_request - frees a request object
332 * @ep:the endpoint associated with the request
333 * @req:the request being freed
335 * Reverses the effect of usb_ep_alloc_request().
336 * Caller guarantees the request is not queued, and that it will
337 * no longer be requeued (or otherwise used).
339 static inline void usb_ep_free_request(struct usb_ep
*ep
,
340 struct usb_request
*req
)
342 ep
->ops
->free_request(ep
, req
);
346 * usb_ep_queue - queues (submits) an I/O request to an endpoint.
347 * @ep:the endpoint associated with the request
348 * @req:the request being submitted
349 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
350 * pre-allocate all necessary memory with the request.
352 * This tells the device controller to perform the specified request through
353 * that endpoint (reading or writing a buffer). When the request completes,
354 * including being canceled by usb_ep_dequeue(), the request's completion
355 * routine is called to return the request to the driver. Any endpoint
356 * (except control endpoints like ep0) may have more than one transfer
357 * request queued; they complete in FIFO order. Once a gadget driver
358 * submits a request, that request may not be examined or modified until it
359 * is given back to that driver through the completion callback.
361 * Each request is turned into one or more packets. The controller driver
362 * never merges adjacent requests into the same packet. OUT transfers
363 * will sometimes use data that's already buffered in the hardware.
364 * Drivers can rely on the fact that the first byte of the request's buffer
365 * always corresponds to the first byte of some USB packet, for both
366 * IN and OUT transfers.
368 * Bulk endpoints can queue any amount of data; the transfer is packetized
369 * automatically. The last packet will be short if the request doesn't fill it
370 * out completely. Zero length packets (ZLPs) should be avoided in portable
371 * protocols since not all usb hardware can successfully handle zero length
372 * packets. (ZLPs may be explicitly written, and may be implicitly written if
373 * the request 'zero' flag is set.) Bulk endpoints may also be used
374 * for interrupt transfers; but the reverse is not true, and some endpoints
375 * won't support every interrupt transfer. (Such as 768 byte packets.)
377 * Interrupt-only endpoints are less functional than bulk endpoints, for
378 * example by not supporting queueing or not handling buffers that are
379 * larger than the endpoint's maxpacket size. They may also treat data
380 * toggle differently.
382 * Control endpoints ... after getting a setup() callback, the driver queues
383 * one response (even if it would be zero length). That enables the
384 * status ack, after transferring data as specified in the response. Setup
385 * functions may return negative error codes to generate protocol stalls.
386 * (Note that some USB device controllers disallow protocol stall responses
387 * in some cases.) When control responses are deferred (the response is
388 * written after the setup callback returns), then usb_ep_set_halt() may be
389 * used on ep0 to trigger protocol stalls. Depending on the controller,
390 * it may not be possible to trigger a status-stage protocol stall when the
391 * data stage is over, that is, from within the response's completion
394 * For periodic endpoints, like interrupt or isochronous ones, the usb host
395 * arranges to poll once per interval, and the gadget driver usually will
396 * have queued some data to transfer at that time.
398 * Returns zero, or a negative error code. Endpoints that are not enabled
399 * report errors; errors will also be
400 * reported when the usb peripheral is disconnected.
402 static inline int usb_ep_queue(struct usb_ep
*ep
,
403 struct usb_request
*req
, gfp_t gfp_flags
)
405 if (WARN_ON_ONCE(!ep
->enabled
&& ep
->address
))
408 return ep
->ops
->queue(ep
, req
, gfp_flags
);
412 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
413 * @ep:the endpoint associated with the request
414 * @req:the request being canceled
416 * If the request is still active on the endpoint, it is dequeued and its
417 * completion routine is called (with status -ECONNRESET); else a negative
418 * error code is returned. This is guaranteed to happen before the call to
419 * usb_ep_dequeue() returns.
421 * Note that some hardware can't clear out write fifos (to unlink the request
422 * at the head of the queue) except as part of disconnecting from usb. Such
423 * restrictions prevent drivers from supporting configuration changes,
424 * even to configuration zero (a "chapter 9" requirement).
426 static inline int usb_ep_dequeue(struct usb_ep
*ep
, struct usb_request
*req
)
428 return ep
->ops
->dequeue(ep
, req
);
432 * usb_ep_set_halt - sets the endpoint halt feature.
433 * @ep: the non-isochronous endpoint being stalled
435 * Use this to stall an endpoint, perhaps as an error report.
436 * Except for control endpoints,
437 * the endpoint stays halted (will not stream any data) until the host
438 * clears this feature; drivers may need to empty the endpoint's request
439 * queue first, to make sure no inappropriate transfers happen.
441 * Note that while an endpoint CLEAR_FEATURE will be invisible to the
442 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the
443 * current altsetting, see usb_ep_clear_halt(). When switching altsettings,
444 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
446 * Returns zero, or a negative error code. On success, this call sets
447 * underlying hardware state that blocks data transfers.
448 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
449 * transfer requests are still queued, or if the controller hardware
450 * (usually a FIFO) still holds bytes that the host hasn't collected.
452 static inline int usb_ep_set_halt(struct usb_ep
*ep
)
454 return ep
->ops
->set_halt(ep
, 1);
458 * usb_ep_clear_halt - clears endpoint halt, and resets toggle
459 * @ep:the bulk or interrupt endpoint being reset
461 * Use this when responding to the standard usb "set interface" request,
462 * for endpoints that aren't reconfigured, after clearing any other state
463 * in the endpoint's i/o queue.
465 * Returns zero, or a negative error code. On success, this call clears
466 * the underlying hardware state reflecting endpoint halt and data toggle.
467 * Note that some hardware can't support this request (like pxa2xx_udc),
468 * and accordingly can't correctly implement interface altsettings.
470 static inline int usb_ep_clear_halt(struct usb_ep
*ep
)
472 return ep
->ops
->set_halt(ep
, 0);
476 * usb_ep_set_wedge - sets the halt feature and ignores clear requests
477 * @ep: the endpoint being wedged
479 * Use this to stall an endpoint and ignore CLEAR_FEATURE(HALT_ENDPOINT)
480 * requests. If the gadget driver clears the halt status, it will
481 * automatically unwedge the endpoint.
483 * Returns zero on success, else negative errno.
486 usb_ep_set_wedge(struct usb_ep
*ep
)
488 if (ep
->ops
->set_wedge
)
489 return ep
->ops
->set_wedge(ep
);
491 return ep
->ops
->set_halt(ep
, 1);
495 * usb_ep_fifo_status - returns number of bytes in fifo, or error
496 * @ep: the endpoint whose fifo status is being checked.
498 * FIFO endpoints may have "unclaimed data" in them in certain cases,
499 * such as after aborted transfers. Hosts may not have collected all
500 * the IN data written by the gadget driver (and reported by a request
501 * completion). The gadget driver may not have collected all the data
502 * written OUT to it by the host. Drivers that need precise handling for
503 * fault reporting or recovery may need to use this call.
505 * This returns the number of such bytes in the fifo, or a negative
506 * errno if the endpoint doesn't use a FIFO or doesn't support such
509 static inline int usb_ep_fifo_status(struct usb_ep
*ep
)
511 if (ep
->ops
->fifo_status
)
512 return ep
->ops
->fifo_status(ep
);
518 * usb_ep_fifo_flush - flushes contents of a fifo
519 * @ep: the endpoint whose fifo is being flushed.
521 * This call may be used to flush the "unclaimed data" that may exist in
522 * an endpoint fifo after abnormal transaction terminations. The call
523 * must never be used except when endpoint is not being used for any
524 * protocol translation.
526 static inline void usb_ep_fifo_flush(struct usb_ep
*ep
)
528 if (ep
->ops
->fifo_flush
)
529 ep
->ops
->fifo_flush(ep
);
533 /*-------------------------------------------------------------------------*/
535 struct usb_dcd_config_params
{
536 __u8 bU1devExitLat
; /* U1 Device exit Latency */
537 #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */
538 __le16 bU2DevExitLat
; /* U2 Device exit Latency */
539 #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */
544 struct usb_gadget_driver
;
547 /* the rest of the api to the controller hardware: device operations,
548 * which don't involve endpoints (or i/o).
550 struct usb_gadget_ops
{
551 int (*get_frame
)(struct usb_gadget
*);
552 int (*wakeup
)(struct usb_gadget
*);
553 int (*set_selfpowered
) (struct usb_gadget
*, int is_selfpowered
);
554 int (*vbus_session
) (struct usb_gadget
*, int is_active
);
555 int (*vbus_draw
) (struct usb_gadget
*, unsigned mA
);
556 int (*pullup
) (struct usb_gadget
*, int is_on
);
557 int (*ioctl
)(struct usb_gadget
*,
558 unsigned code
, unsigned long param
);
559 void (*get_config_params
)(struct usb_dcd_config_params
*);
560 int (*udc_start
)(struct usb_gadget
*,
561 struct usb_gadget_driver
*);
562 int (*udc_stop
)(struct usb_gadget
*);
563 struct usb_ep
*(*match_ep
)(struct usb_gadget
*,
564 struct usb_endpoint_descriptor
*,
565 struct usb_ss_ep_comp_descriptor
*);
569 * struct usb_gadget - represents a usb slave device
570 * @work: (internal use) Workqueue to be used for sysfs_notify()
571 * @udc: struct usb_udc pointer for this gadget
572 * @ops: Function pointers used to access hardware-specific operations.
573 * @ep0: Endpoint zero, used when reading or writing responses to
574 * driver setup() requests
575 * @ep_list: List of other endpoints supported by the device.
576 * @speed: Speed of current connection to USB host.
577 * @max_speed: Maximal speed the UDC can handle. UDC must support this
578 * and all slower speeds.
579 * @state: the state we are now (attached, suspended, configured, etc)
580 * @name: Identifies the controller hardware type. Used in diagnostics
581 * and sometimes configuration.
582 * @dev: Driver model state for this abstract device.
583 * @out_epnum: last used out ep number
584 * @in_epnum: last used in ep number
585 * @otg_caps: OTG capabilities of this gadget.
586 * @sg_supported: true if we can handle scatter-gather
587 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the
588 * gadget driver must provide a USB OTG descriptor.
589 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable
590 * is in the Mini-AB jack, and HNP has been used to switch roles
591 * so that the "A" device currently acts as A-Peripheral, not A-Host.
592 * @a_hnp_support: OTG device feature flag, indicating that the A-Host
593 * supports HNP at this port.
594 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host
595 * only supports HNP on a different root port.
596 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host
597 * enabled HNP support.
598 * @hnp_polling_support: OTG device feature flag, indicating if the OTG device
599 * in peripheral mode can support HNP polling.
600 * @host_request_flag: OTG device feature flag, indicating if A-Peripheral
601 * or B-Peripheral wants to take host role.
602 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to
604 * @is_selfpowered: if the gadget is self-powered.
605 * @deactivated: True if gadget is deactivated - in deactivated state it cannot
607 * @connected: True if gadget is connected.
609 * Gadgets have a mostly-portable "gadget driver" implementing device
610 * functions, handling all usb configurations and interfaces. Gadget
611 * drivers talk to hardware-specific code indirectly, through ops vectors.
612 * That insulates the gadget driver from hardware details, and packages
613 * the hardware endpoints through generic i/o queues. The "usb_gadget"
614 * and "usb_ep" interfaces provide that insulation from the hardware.
616 * Except for the driver data, all fields in this structure are
617 * read-only to the gadget driver. That driver data is part of the
618 * "driver model" infrastructure in 2.6 (and later) kernels, and for
619 * earlier systems is grouped in a similar structure that's not known
620 * to the rest of the kernel.
622 * Values of the three OTG device feature flags are updated before the
623 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before
624 * driver suspend() calls. They are valid only when is_otg, and when the
625 * device is acting as a B-Peripheral (so is_a_peripheral is false).
628 struct work_struct work
;
630 /* readonly to gadget driver */
631 const struct usb_gadget_ops
*ops
;
633 struct list_head ep_list
; /* of usb_ep */
634 enum usb_device_speed speed
;
635 enum usb_device_speed max_speed
;
636 enum usb_device_state state
;
641 struct usb_otg_caps
*otg_caps
;
643 unsigned sg_supported
:1;
645 unsigned is_a_peripheral
:1;
646 unsigned b_hnp_enable
:1;
647 unsigned a_hnp_support
:1;
648 unsigned a_alt_hnp_support
:1;
649 unsigned hnp_polling_support
:1;
650 unsigned host_request_flag
:1;
651 unsigned quirk_ep_out_aligned_size
:1;
652 unsigned quirk_altset_not_supp
:1;
653 unsigned quirk_stall_not_supp
:1;
654 unsigned quirk_zlp_not_supp
:1;
655 unsigned is_selfpowered
:1;
656 unsigned deactivated
:1;
657 unsigned connected
:1;
659 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work))
661 static inline void set_gadget_data(struct usb_gadget
*gadget
, void *data
)
662 { dev_set_drvdata(&gadget
->dev
, data
); }
663 static inline void *get_gadget_data(struct usb_gadget
*gadget
)
664 { return dev_get_drvdata(&gadget
->dev
); }
665 static inline struct usb_gadget
*dev_to_usb_gadget(struct device
*dev
)
667 return container_of(dev
, struct usb_gadget
, dev
);
670 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */
671 #define gadget_for_each_ep(tmp, gadget) \
672 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list)
675 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget
676 * requires quirk_ep_out_aligned_size, otherwise reguens len.
677 * @g: controller to check for quirk
678 * @ep: the endpoint whose maxpacketsize is used to align @len
679 * @len: buffer size's length to align to @ep's maxpacketsize
681 * This helper is used in case it's required for any reason to check and maybe
682 * align buffer's size to an ep's maxpacketsize.
685 usb_ep_align_maybe(struct usb_gadget
*g
, struct usb_ep
*ep
, size_t len
)
687 return !g
->quirk_ep_out_aligned_size
? len
:
688 round_up(len
, (size_t)ep
->desc
->wMaxPacketSize
);
692 * gadget_is_altset_supported - return true iff the hardware supports
694 * @g: controller to check for quirk
696 static inline int gadget_is_altset_supported(struct usb_gadget
*g
)
698 return !g
->quirk_altset_not_supp
;
702 * gadget_is_stall_supported - return true iff the hardware supports stalling
703 * @g: controller to check for quirk
705 static inline int gadget_is_stall_supported(struct usb_gadget
*g
)
707 return !g
->quirk_stall_not_supp
;
711 * gadget_is_zlp_supported - return true iff the hardware supports zlp
712 * @g: controller to check for quirk
714 static inline int gadget_is_zlp_supported(struct usb_gadget
*g
)
716 return !g
->quirk_zlp_not_supp
;
720 * gadget_is_dualspeed - return true iff the hardware handles high speed
721 * @g: controller that might support both high and full speeds
723 static inline int gadget_is_dualspeed(struct usb_gadget
*g
)
725 return g
->max_speed
>= USB_SPEED_HIGH
;
729 * gadget_is_superspeed() - return true if the hardware handles superspeed
730 * @g: controller that might support superspeed
732 static inline int gadget_is_superspeed(struct usb_gadget
*g
)
734 return g
->max_speed
>= USB_SPEED_SUPER
;
738 * gadget_is_superspeed_plus() - return true if the hardware handles
740 * @g: controller that might support superspeed plus
742 static inline int gadget_is_superspeed_plus(struct usb_gadget
*g
)
744 return g
->max_speed
>= USB_SPEED_SUPER_PLUS
;
748 * gadget_is_otg - return true iff the hardware is OTG-ready
749 * @g: controller that might have a Mini-AB connector
751 * This is a runtime test, since kernels with a USB-OTG stack sometimes
752 * run on boards which only have a Mini-B (or Mini-A) connector.
754 static inline int gadget_is_otg(struct usb_gadget
*g
)
756 #ifdef CONFIG_USB_OTG
764 * usb_gadget_frame_number - returns the current frame number
765 * @gadget: controller that reports the frame number
767 * Returns the usb frame number, normally eleven bits from a SOF packet,
768 * or negative errno if this device doesn't support this capability.
770 static inline int usb_gadget_frame_number(struct usb_gadget
*gadget
)
772 return gadget
->ops
->get_frame(gadget
);
776 * usb_gadget_wakeup - tries to wake up the host connected to this gadget
777 * @gadget: controller used to wake up the host
779 * Returns zero on success, else negative error code if the hardware
780 * doesn't support such attempts, or its support has not been enabled
781 * by the usb host. Drivers must return device descriptors that report
782 * their ability to support this, or hosts won't enable it.
784 * This may also try to use SRP to wake the host and start enumeration,
785 * even if OTG isn't otherwise in use. OTG devices may also start
786 * remote wakeup even when hosts don't explicitly enable it.
788 static inline int usb_gadget_wakeup(struct usb_gadget
*gadget
)
790 if (!gadget
->ops
->wakeup
)
792 return gadget
->ops
->wakeup(gadget
);
796 * usb_gadget_set_selfpowered - sets the device selfpowered feature.
797 * @gadget:the device being declared as self-powered
799 * this affects the device status reported by the hardware driver
800 * to reflect that it now has a local power supply.
802 * returns zero on success, else negative errno.
804 static inline int usb_gadget_set_selfpowered(struct usb_gadget
*gadget
)
806 if (!gadget
->ops
->set_selfpowered
)
808 return gadget
->ops
->set_selfpowered(gadget
, 1);
812 * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
813 * @gadget:the device being declared as bus-powered
815 * this affects the device status reported by the hardware driver.
816 * some hardware may not support bus-powered operation, in which
817 * case this feature's value can never change.
819 * returns zero on success, else negative errno.
821 static inline int usb_gadget_clear_selfpowered(struct usb_gadget
*gadget
)
823 if (!gadget
->ops
->set_selfpowered
)
825 return gadget
->ops
->set_selfpowered(gadget
, 0);
829 * usb_gadget_vbus_connect - Notify controller that VBUS is powered
830 * @gadget:The device which now has VBUS power.
833 * This call is used by a driver for an external transceiver (or GPIO)
834 * that detects a VBUS power session starting. Common responses include
835 * resuming the controller, activating the D+ (or D-) pullup to let the
836 * host detect that a USB device is attached, and starting to draw power
837 * (8mA or possibly more, especially after SET_CONFIGURATION).
839 * Returns zero on success, else negative errno.
841 static inline int usb_gadget_vbus_connect(struct usb_gadget
*gadget
)
843 if (!gadget
->ops
->vbus_session
)
845 return gadget
->ops
->vbus_session(gadget
, 1);
849 * usb_gadget_vbus_draw - constrain controller's VBUS power usage
850 * @gadget:The device whose VBUS usage is being described
851 * @mA:How much current to draw, in milliAmperes. This should be twice
852 * the value listed in the configuration descriptor bMaxPower field.
854 * This call is used by gadget drivers during SET_CONFIGURATION calls,
855 * reporting how much power the device may consume. For example, this
856 * could affect how quickly batteries are recharged.
858 * Returns zero on success, else negative errno.
860 static inline int usb_gadget_vbus_draw(struct usb_gadget
*gadget
, unsigned mA
)
862 if (!gadget
->ops
->vbus_draw
)
864 return gadget
->ops
->vbus_draw(gadget
, mA
);
868 * usb_gadget_vbus_disconnect - notify controller about VBUS session end
869 * @gadget:the device whose VBUS supply is being described
872 * This call is used by a driver for an external transceiver (or GPIO)
873 * that detects a VBUS power session ending. Common responses include
874 * reversing everything done in usb_gadget_vbus_connect().
876 * Returns zero on success, else negative errno.
878 static inline int usb_gadget_vbus_disconnect(struct usb_gadget
*gadget
)
880 if (!gadget
->ops
->vbus_session
)
882 return gadget
->ops
->vbus_session(gadget
, 0);
886 * usb_gadget_connect - software-controlled connect to USB host
887 * @gadget:the peripheral being connected
889 * Enables the D+ (or potentially D-) pullup. The host will start
890 * enumerating this gadget when the pullup is active and a VBUS session
891 * is active (the link is powered). This pullup is always enabled unless
892 * usb_gadget_disconnect() has been used to disable it.
894 * Returns zero on success, else negative errno.
896 static inline int usb_gadget_connect(struct usb_gadget
*gadget
)
900 if (!gadget
->ops
->pullup
)
903 if (gadget
->deactivated
) {
905 * If gadget is deactivated we only save new state.
906 * Gadget will be connected automatically after activation.
908 gadget
->connected
= true;
912 ret
= gadget
->ops
->pullup(gadget
, 1);
914 gadget
->connected
= 1;
919 * usb_gadget_disconnect - software-controlled disconnect from USB host
920 * @gadget:the peripheral being disconnected
922 * Disables the D+ (or potentially D-) pullup, which the host may see
923 * as a disconnect (when a VBUS session is active). Not all systems
924 * support software pullup controls.
926 * Returns zero on success, else negative errno.
928 static inline int usb_gadget_disconnect(struct usb_gadget
*gadget
)
932 if (!gadget
->ops
->pullup
)
935 if (gadget
->deactivated
) {
937 * If gadget is deactivated we only save new state.
938 * Gadget will stay disconnected after activation.
940 gadget
->connected
= false;
944 ret
= gadget
->ops
->pullup(gadget
, 0);
946 gadget
->connected
= 0;
951 * usb_gadget_deactivate - deactivate function which is not ready to work
952 * @gadget: the peripheral being deactivated
954 * This routine may be used during the gadget driver bind() call to prevent
955 * the peripheral from ever being visible to the USB host, unless later
956 * usb_gadget_activate() is called. For example, user mode components may
957 * need to be activated before the system can talk to hosts.
959 * Returns zero on success, else negative errno.
961 static inline int usb_gadget_deactivate(struct usb_gadget
*gadget
)
965 if (gadget
->deactivated
)
968 if (gadget
->connected
) {
969 ret
= usb_gadget_disconnect(gadget
);
973 * If gadget was being connected before deactivation, we want
974 * to reconnect it in usb_gadget_activate().
976 gadget
->connected
= true;
978 gadget
->deactivated
= true;
984 * usb_gadget_activate - activate function which is not ready to work
985 * @gadget: the peripheral being activated
987 * This routine activates gadget which was previously deactivated with
988 * usb_gadget_deactivate() call. It calls usb_gadget_connect() if needed.
990 * Returns zero on success, else negative errno.
992 static inline int usb_gadget_activate(struct usb_gadget
*gadget
)
994 if (!gadget
->deactivated
)
997 gadget
->deactivated
= false;
1000 * If gadget has been connected before deactivation, or became connected
1001 * while it was being deactivated, we call usb_gadget_connect().
1003 if (gadget
->connected
)
1004 return usb_gadget_connect(gadget
);
1009 /*-------------------------------------------------------------------------*/
1012 * struct usb_gadget_driver - driver for usb 'slave' devices
1013 * @function: String describing the gadget's function
1014 * @max_speed: Highest speed the driver handles.
1015 * @setup: Invoked for ep0 control requests that aren't handled by
1016 * the hardware level driver. Most calls must be handled by
1017 * the gadget driver, including descriptor and configuration
1018 * management. The 16 bit members of the setup data are in
1019 * USB byte order. Called in_interrupt; this may not sleep. Driver
1020 * queues a response to ep0, or returns negative to stall.
1021 * @disconnect: Invoked after all transfers have been stopped,
1022 * when the host is disconnected. May be called in_interrupt; this
1023 * may not sleep. Some devices can't detect disconnect, so this might
1024 * not be called except as part of controller shutdown.
1025 * @bind: the driver's bind callback
1026 * @unbind: Invoked when the driver is unbound from a gadget,
1027 * usually from rmmod (after a disconnect is reported).
1028 * Called in a context that permits sleeping.
1029 * @suspend: Invoked on USB suspend. May be called in_interrupt.
1030 * @resume: Invoked on USB resume. May be called in_interrupt.
1031 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers
1032 * and should be called in_interrupt.
1033 * @driver: Driver model state for this driver.
1034 * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL,
1035 * this driver will be bound to any available UDC.
1036 * @pending: UDC core private data used for deferred probe of this driver.
1038 * Devices are disabled till a gadget driver successfully bind()s, which
1039 * means the driver will handle setup() requests needed to enumerate (and
1040 * meet "chapter 9" requirements) then do some useful work.
1042 * If gadget->is_otg is true, the gadget driver must provide an OTG
1043 * descriptor during enumeration, or else fail the bind() call. In such
1044 * cases, no USB traffic may flow until both bind() returns without
1045 * having called usb_gadget_disconnect(), and the USB host stack has
1048 * Drivers use hardware-specific knowledge to configure the usb hardware.
1049 * endpoint addressing is only one of several hardware characteristics that
1050 * are in descriptors the ep0 implementation returns from setup() calls.
1052 * Except for ep0 implementation, most driver code shouldn't need change to
1053 * run on top of different usb controllers. It'll use endpoints set up by
1054 * that ep0 implementation.
1056 * The usb controller driver handles a few standard usb requests. Those
1057 * include set_address, and feature flags for devices, interfaces, and
1058 * endpoints (the get_status, set_feature, and clear_feature requests).
1060 * Accordingly, the driver's setup() callback must always implement all
1061 * get_descriptor requests, returning at least a device descriptor and
1062 * a configuration descriptor. Drivers must make sure the endpoint
1063 * descriptors match any hardware constraints. Some hardware also constrains
1064 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3).
1066 * The driver's setup() callback must also implement set_configuration,
1067 * and should also implement set_interface, get_configuration, and
1068 * get_interface. Setting a configuration (or interface) is where
1069 * endpoints should be activated or (config 0) shut down.
1071 * (Note that only the default control endpoint is supported. Neither
1072 * hosts nor devices generally support control traffic except to ep0.)
1074 * Most devices will ignore USB suspend/resume operations, and so will
1075 * not provide those callbacks. However, some may need to change modes
1076 * when the host is not longer directing those activities. For example,
1077 * local controls (buttons, dials, etc) may need to be re-enabled since
1078 * the (remote) host can't do that any longer; or an error state might
1079 * be cleared, to make the device behave identically whether or not
1080 * power is maintained.
1082 struct usb_gadget_driver
{
1084 enum usb_device_speed max_speed
;
1085 int (*bind
)(struct usb_gadget
*gadget
,
1086 struct usb_gadget_driver
*driver
);
1087 void (*unbind
)(struct usb_gadget
*);
1088 int (*setup
)(struct usb_gadget
*,
1089 const struct usb_ctrlrequest
*);
1090 void (*disconnect
)(struct usb_gadget
*);
1091 void (*suspend
)(struct usb_gadget
*);
1092 void (*resume
)(struct usb_gadget
*);
1093 void (*reset
)(struct usb_gadget
*);
1095 /* FIXME support safe rmmod */
1096 struct device_driver driver
;
1099 struct list_head pending
;
1104 /*-------------------------------------------------------------------------*/
1106 /* driver modules register and unregister, as usual.
1107 * these calls must be made in a context that can sleep.
1109 * these will usually be implemented directly by the hardware-dependent
1110 * usb bus interface driver, which will only support a single driver.
1114 * usb_gadget_probe_driver - probe a gadget driver
1115 * @driver: the driver being registered
1116 * Context: can sleep
1118 * Call this in your gadget driver's module initialization function,
1119 * to tell the underlying usb controller driver about your driver.
1120 * The @bind() function will be called to bind it to a gadget before this
1121 * registration call returns. It's expected that the @bind() function will
1122 * be in init sections.
1124 int usb_gadget_probe_driver(struct usb_gadget_driver
*driver
);
1127 * usb_gadget_unregister_driver - unregister a gadget driver
1128 * @driver:the driver being unregistered
1129 * Context: can sleep
1131 * Call this in your gadget driver's module cleanup function,
1132 * to tell the underlying usb controller that your driver is
1133 * going away. If the controller is connected to a USB host,
1134 * it will first disconnect(). The driver is also requested
1135 * to unbind() and clean up any device state, before this procedure
1136 * finally returns. It's expected that the unbind() functions
1137 * will in in exit sections, so may not be linked in some kernels.
1139 int usb_gadget_unregister_driver(struct usb_gadget_driver
*driver
);
1141 extern int usb_add_gadget_udc_release(struct device
*parent
,
1142 struct usb_gadget
*gadget
, void (*release
)(struct device
*dev
));
1143 extern int usb_add_gadget_udc(struct device
*parent
, struct usb_gadget
*gadget
);
1144 extern void usb_del_gadget_udc(struct usb_gadget
*gadget
);
1145 extern char *usb_get_gadget_udc_name(void);
1147 /*-------------------------------------------------------------------------*/
1149 /* utility to simplify dealing with string descriptors */
1152 * struct usb_string - wraps a C string and its USB id
1153 * @id:the (nonzero) ID for this string
1154 * @s:the string, in UTF-8 encoding
1156 * If you're using usb_gadget_get_string(), use this to wrap a string
1157 * together with its ID.
1165 * struct usb_gadget_strings - a set of USB strings in a given language
1166 * @language:identifies the strings' language (0x0409 for en-us)
1167 * @strings:array of strings with their ids
1169 * If you're using usb_gadget_get_string(), use this to wrap all the
1170 * strings for a given language.
1172 struct usb_gadget_strings
{
1173 u16 language
; /* 0x0409 for en-us */
1174 struct usb_string
*strings
;
1177 struct usb_gadget_string_container
{
1178 struct list_head list
;
1182 /* put descriptor for string with that id into buf (buflen >= 256) */
1183 int usb_gadget_get_string(struct usb_gadget_strings
*table
, int id
, u8
*buf
);
1185 /*-------------------------------------------------------------------------*/
1187 /* utility to simplify managing config descriptors */
1189 /* write vector of descriptors into buffer */
1190 int usb_descriptor_fillbuf(void *, unsigned,
1191 const struct usb_descriptor_header
**);
1193 /* build config descriptor from single descriptor vector */
1194 int usb_gadget_config_buf(const struct usb_config_descriptor
*config
,
1195 void *buf
, unsigned buflen
, const struct usb_descriptor_header
**desc
);
1197 /* copy a NULL-terminated vector of descriptors */
1198 struct usb_descriptor_header
**usb_copy_descriptors(
1199 struct usb_descriptor_header
**);
1202 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors()
1203 * @v: vector of descriptors
1205 static inline void usb_free_descriptors(struct usb_descriptor_header
**v
)
1210 struct usb_function
;
1211 int usb_assign_descriptors(struct usb_function
*f
,
1212 struct usb_descriptor_header
**fs
,
1213 struct usb_descriptor_header
**hs
,
1214 struct usb_descriptor_header
**ss
,
1215 struct usb_descriptor_header
**ssp
);
1216 void usb_free_all_descriptors(struct usb_function
*f
);
1218 struct usb_descriptor_header
*usb_otg_descriptor_alloc(
1219 struct usb_gadget
*gadget
);
1220 int usb_otg_descriptor_init(struct usb_gadget
*gadget
,
1221 struct usb_descriptor_header
*otg_desc
);
1222 /*-------------------------------------------------------------------------*/
1224 /* utility to simplify map/unmap of usb_requests to/from DMA */
1226 extern int usb_gadget_map_request_by_dev(struct device
*dev
,
1227 struct usb_request
*req
, int is_in
);
1228 extern int usb_gadget_map_request(struct usb_gadget
*gadget
,
1229 struct usb_request
*req
, int is_in
);
1231 extern void usb_gadget_unmap_request_by_dev(struct device
*dev
,
1232 struct usb_request
*req
, int is_in
);
1233 extern void usb_gadget_unmap_request(struct usb_gadget
*gadget
,
1234 struct usb_request
*req
, int is_in
);
1236 /*-------------------------------------------------------------------------*/
1238 /* utility to set gadget state properly */
1240 extern void usb_gadget_set_state(struct usb_gadget
*gadget
,
1241 enum usb_device_state state
);
1243 /*-------------------------------------------------------------------------*/
1245 /* utility to tell udc core that the bus reset occurs */
1246 extern void usb_gadget_udc_reset(struct usb_gadget
*gadget
,
1247 struct usb_gadget_driver
*driver
);
1249 /*-------------------------------------------------------------------------*/
1251 /* utility to give requests back to the gadget layer */
1253 extern void usb_gadget_giveback_request(struct usb_ep
*ep
,
1254 struct usb_request
*req
);
1256 /*-------------------------------------------------------------------------*/
1258 /* utility to find endpoint by name */
1260 extern struct usb_ep
*gadget_find_ep_by_name(struct usb_gadget
*g
,
1263 /*-------------------------------------------------------------------------*/
1265 /* utility to check if endpoint caps match descriptor needs */
1267 extern int usb_gadget_ep_match_desc(struct usb_gadget
*gadget
,
1268 struct usb_ep
*ep
, struct usb_endpoint_descriptor
*desc
,
1269 struct usb_ss_ep_comp_descriptor
*ep_comp
);
1271 /*-------------------------------------------------------------------------*/
1273 /* utility to update vbus status for udc core, it may be scheduled */
1274 extern void usb_udc_vbus_handler(struct usb_gadget
*gadget
, bool status
);
1276 /*-------------------------------------------------------------------------*/
1278 /* utility wrapping a simple endpoint selection policy */
1280 extern struct usb_ep
*usb_ep_autoconfig(struct usb_gadget
*,
1281 struct usb_endpoint_descriptor
*);
1284 extern struct usb_ep
*usb_ep_autoconfig_ss(struct usb_gadget
*,
1285 struct usb_endpoint_descriptor
*,
1286 struct usb_ss_ep_comp_descriptor
*);
1288 extern void usb_ep_autoconfig_release(struct usb_ep
*);
1290 extern void usb_ep_autoconfig_reset(struct usb_gadget
*);
1292 #endif /* __LINUX_USB_GADGET_H */