1/* 2 * <linux/usb/gadget.h> 3 * 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. 7 * 8 * 9 * (C) Copyright 2002-2004 by David Brownell 10 * All Rights Reserved. 11 * 12 * This software is licensed under the GNU GPL version 2. 13 * 14 * Ported to U-Boot by: Thomas Smits <ts.smits@gmail.com> and 15 * Remy Bohmer <linux@bohmer.net> 16 */ 17 18#ifndef __LINUX_USB_GADGET_H 19#define __LINUX_USB_GADGET_H 20 21#include <errno.h> 22#include <usb.h> 23#include <linux/compat.h> 24#include <linux/list.h> 25 26struct usb_ep; 27 28/** 29 * struct usb_request - describes one i/o request 30 * @buf: Buffer used for data. Always provide this; some controllers 31 * only use PIO, or don't use DMA for some endpoints. 32 * @dma: DMA address corresponding to 'buf'. If you don't set this 33 * field, and the usb controller needs one, it is responsible 34 * for mapping and unmapping the buffer. 35 * @stream_id: The stream id, when USB3.0 bulk streams are being used 36 * @length: Length of that data 37 * @no_interrupt: If true, hints that no completion irq is needed. 38 * Helpful sometimes with deep request queues that are handled 39 * directly by DMA controllers. 40 * @zero: If true, when writing data, makes the last packet be "short" 41 * by adding a zero length packet as needed; 42 * @short_not_ok: When reading data, makes short packets be 43 * treated as errors (queue stops advancing till cleanup). 44 * @complete: Function called when request completes, so this request and 45 * its buffer may be re-used. 46 * Reads terminate with a short packet, or when the buffer fills, 47 * whichever comes first. When writes terminate, some data bytes 48 * will usually still be in flight (often in a hardware fifo). 49 * Errors (for reads or writes) stop the queue from advancing 50 * until the completion function returns, so that any transfers 51 * invalidated by the error may first be dequeued. 52 * @context: For use by the completion callback 53 * @list: For use by the gadget driver. 54 * @status: Reports completion code, zero or a negative errno. 55 * Normally, faults block the transfer queue from advancing until 56 * the completion callback returns. 57 * Code "-ESHUTDOWN" indicates completion caused by device disconnect, 58 * or when the driver disabled the endpoint. 59 * @actual: Reports bytes transferred to/from the buffer. For reads (OUT 60 * transfers) this may be less than the requested length. If the 61 * short_not_ok flag is set, short reads are treated as errors 62 * even when status otherwise indicates successful completion. 63 * Note that for writes (IN transfers) some data bytes may still 64 * reside in a device-side FIFO when the request is reported as 65 * complete. 66 * 67 * These are allocated/freed through the endpoint they're used with. The 68 * hardware's driver can add extra per-request data to the memory it returns, 69 * which often avoids separate memory allocations (potential failures), 70 * later when the request is queued. 71 * 72 * Request flags affect request handling, such as whether a zero length 73 * packet is written (the "zero" flag), whether a short read should be 74 * treated as an error (blocking request queue advance, the "short_not_ok" 75 * flag), or hinting that an interrupt is not required (the "no_interrupt" 76 * flag, for use with deep request queues). 77 * 78 * Bulk endpoints can use any size buffers, and can also be used for interrupt 79 * transfers. interrupt-only endpoints can be much less functional. 80 * 81 * NOTE: this is analagous to 'struct urb' on the host side, except that 82 * it's thinner and promotes more pre-allocation. 83 */ 84 85struct usb_request { 86 void *buf; 87 unsigned length; 88 dma_addr_t dma; 89 90 unsigned stream_id:16; 91 unsigned no_interrupt:1; 92 unsigned zero:1; 93 unsigned short_not_ok:1; 94 95 void (*complete)(struct usb_ep *ep, 96 struct usb_request *req); 97 void *context; 98 struct list_head list; 99 100 int status; 101 unsigned actual; 102}; 103 104/*-------------------------------------------------------------------------*/ 105 106/* endpoint-specific parts of the api to the usb controller hardware. 107 * unlike the urb model, (de)multiplexing layers are not required. 108 * (so this api could slash overhead if used on the host side...) 109 * 110 * note that device side usb controllers commonly differ in how many 111 * endpoints they support, as well as their capabilities. 112 */ 113struct usb_ep_ops { 114 int (*enable) (struct usb_ep *ep, 115 const struct usb_endpoint_descriptor *desc); 116 int (*disable) (struct usb_ep *ep); 117 118 struct usb_request *(*alloc_request) (struct usb_ep *ep, 119 gfp_t gfp_flags); 120 void (*free_request) (struct usb_ep *ep, struct usb_request *req); 121 122 int (*queue) (struct usb_ep *ep, struct usb_request *req, 123 gfp_t gfp_flags); 124 int (*dequeue) (struct usb_ep *ep, struct usb_request *req); 125 126 int (*set_halt) (struct usb_ep *ep, int value); 127 int (*set_wedge)(struct usb_ep *ep); 128 int (*fifo_status) (struct usb_ep *ep); 129 void (*fifo_flush) (struct usb_ep *ep); 130}; 131 132/** 133 * struct usb_ep_caps - endpoint capabilities description 134 * @type_control:Endpoint supports control type (reserved for ep0). 135 * @type_iso:Endpoint supports isochronous transfers. 136 * @type_bulk:Endpoint supports bulk transfers. 137 * @type_int:Endpoint supports interrupt transfers. 138 * @dir_in:Endpoint supports IN direction. 139 * @dir_out:Endpoint supports OUT direction. 140 */ 141struct usb_ep_caps { 142 unsigned type_control:1; 143 unsigned type_iso:1; 144 unsigned type_bulk:1; 145 unsigned type_int:1; 146 unsigned dir_in:1; 147 unsigned dir_out:1; 148}; 149 150/** 151 * struct usb_ep - device side representation of USB endpoint 152 * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk" 153 * @ops: Function pointers used to access hardware-specific operations. 154 * @ep_list:the gadget's ep_list holds all of its endpoints 155 * @caps:The structure describing types and directions supported by endoint. 156 * @maxpacket:The maximum packet size used on this endpoint. The initial 157 * value can sometimes be reduced (hardware allowing), according to 158 * the endpoint descriptor used to configure the endpoint. 159 * @maxpacket_limit:The maximum packet size value which can be handled by this 160 * endpoint. It's set once by UDC driver when endpoint is initialized, and 161 * should not be changed. Should not be confused with maxpacket. 162 * @max_streams: The maximum number of streams supported 163 * by this EP (0 - 16, actual number is 2^n) 164 * @maxburst: the maximum number of bursts supported by this EP (for usb3) 165 * @driver_data:for use by the gadget driver. all other fields are 166 * read-only to gadget drivers. 167 * @desc: endpoint descriptor. This pointer is set before the endpoint is 168 * enabled and remains valid until the endpoint is disabled. 169 * @comp_desc: In case of SuperSpeed support, this is the endpoint companion 170 * descriptor that is used to configure the endpoint 171 * 172 * the bus controller driver lists all the general purpose endpoints in 173 * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, 174 * and is accessed only in response to a driver setup() callback. 175 */ 176struct usb_ep { 177 void *driver_data; 178 const char *name; 179 const struct usb_ep_ops *ops; 180 struct list_head ep_list; 181 struct usb_ep_caps caps; 182 unsigned maxpacket:16; 183 unsigned maxpacket_limit:16; 184 unsigned max_streams:16; 185 unsigned maxburst:5; 186 const struct usb_endpoint_descriptor *desc; 187 const struct usb_ss_ep_comp_descriptor *comp_desc; 188}; 189 190/*-------------------------------------------------------------------------*/ 191 192/** 193 * usb_ep_set_maxpacket_limit - set maximum packet size limit for endpoint 194 * @ep:the endpoint being configured 195 * @maxpacket_limit:value of maximum packet size limit 196 * 197 * This function shoud be used only in UDC drivers to initialize endpoint 198 * (usually in probe function). 199 */ 200static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep, 201 unsigned maxpacket_limit) 202{ 203 ep->maxpacket_limit = maxpacket_limit; 204 ep->maxpacket = maxpacket_limit; 205} 206 207/** 208 * usb_ep_enable - configure endpoint, making it usable 209 * @ep:the endpoint being configured. may not be the endpoint named "ep0". 210 * drivers discover endpoints through the ep_list of a usb_gadget. 211 * @desc:descriptor for desired behavior. caller guarantees this pointer 212 * remains valid until the endpoint is disabled; the data byte order 213 * is little-endian (usb-standard). 214 * 215 * when configurations are set, or when interface settings change, the driver 216 * will enable or disable the relevant endpoints. while it is enabled, an 217 * endpoint may be used for i/o until the driver receives a disconnect() from 218 * the host or until the endpoint is disabled. 219 * 220 * the ep0 implementation (which calls this routine) must ensure that the 221 * hardware capabilities of each endpoint match the descriptor provided 222 * for it. for example, an endpoint named "ep2in-bulk" would be usable 223 * for interrupt transfers as well as bulk, but it likely couldn't be used 224 * for iso transfers or for endpoint 14. some endpoints are fully 225 * configurable, with more generic names like "ep-a". (remember that for 226 * USB, "in" means "towards the USB master".) 227 * 228 * returns zero, or a negative error code. 229 */ 230static inline int usb_ep_enable(struct usb_ep *ep, 231 const struct usb_endpoint_descriptor *desc) 232{ 233 return ep->ops->enable(ep, desc); 234} 235 236/** 237 * usb_ep_disable - endpoint is no longer usable 238 * @ep:the endpoint being unconfigured. may not be the endpoint named "ep0". 239 * 240 * no other task may be using this endpoint when this is called. 241 * any pending and uncompleted requests will complete with status 242 * indicating disconnect (-ESHUTDOWN) before this call returns. 243 * gadget drivers must call usb_ep_enable() again before queueing 244 * requests to the endpoint. 245 * 246 * returns zero, or a negative error code. 247 */ 248static inline int usb_ep_disable(struct usb_ep *ep) 249{ 250 return ep->ops->disable(ep); 251} 252 253/** 254 * usb_ep_alloc_request - allocate a request object to use with this endpoint 255 * @ep:the endpoint to be used with with the request 256 * @gfp_flags:GFP_* flags to use 257 * 258 * Request objects must be allocated with this call, since they normally 259 * need controller-specific setup and may even need endpoint-specific 260 * resources such as allocation of DMA descriptors. 261 * Requests may be submitted with usb_ep_queue(), and receive a single 262 * completion callback. Free requests with usb_ep_free_request(), when 263 * they are no longer needed. 264 * 265 * Returns the request, or null if one could not be allocated. 266 */ 267static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, 268 gfp_t gfp_flags) 269{ 270 return ep->ops->alloc_request(ep, gfp_flags); 271} 272 273/** 274 * usb_ep_free_request - frees a request object 275 * @ep:the endpoint associated with the request 276 * @req:the request being freed 277 * 278 * Reverses the effect of usb_ep_alloc_request(). 279 * Caller guarantees the request is not queued, and that it will 280 * no longer be requeued (or otherwise used). 281 */ 282static inline void usb_ep_free_request(struct usb_ep *ep, 283 struct usb_request *req) 284{ 285 ep->ops->free_request(ep, req); 286} 287 288/** 289 * usb_ep_queue - queues (submits) an I/O request to an endpoint. 290 * @ep:the endpoint associated with the request 291 * @req:the request being submitted 292 * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't 293 * pre-allocate all necessary memory with the request. 294 * 295 * This tells the device controller to perform the specified request through 296 * that endpoint (reading or writing a buffer). When the request completes, 297 * including being canceled by usb_ep_dequeue(), the request's completion 298 * routine is called to return the request to the driver. Any endpoint 299 * (except control endpoints like ep0) may have more than one transfer 300 * request queued; they complete in FIFO order. Once a gadget driver 301 * submits a request, that request may not be examined or modified until it 302 * is given back to that driver through the completion callback. 303 * 304 * Each request is turned into one or more packets. The controller driver 305 * never merges adjacent requests into the same packet. OUT transfers 306 * will sometimes use data that's already buffered in the hardware. 307 * Drivers can rely on the fact that the first byte of the request's buffer 308 * always corresponds to the first byte of some USB packet, for both 309 * IN and OUT transfers. 310 * 311 * Bulk endpoints can queue any amount of data; the transfer is packetized 312 * automatically. The last packet will be short if the request doesn't fill it 313 * out completely. Zero length packets (ZLPs) should be avoided in portable 314 * protocols since not all usb hardware can successfully handle zero length 315 * packets. (ZLPs may be explicitly written, and may be implicitly written if 316 * the request 'zero' flag is set.) Bulk endpoints may also be used 317 * for interrupt transfers; but the reverse is not true, and some endpoints 318 * won't support every interrupt transfer. (Such as 768 byte packets.) 319 * 320 * Interrupt-only endpoints are less functional than bulk endpoints, for 321 * example by not supporting queueing or not handling buffers that are 322 * larger than the endpoint's maxpacket size. They may also treat data 323 * toggle differently. 324 * 325 * Control endpoints ... after getting a setup() callback, the driver queues 326 * one response (even if it would be zero length). That enables the 327 * status ack, after transfering data as specified in the response. Setup 328 * functions may return negative error codes to generate protocol stalls. 329 * (Note that some USB device controllers disallow protocol stall responses 330 * in some cases.) When control responses are deferred (the response is 331 * written after the setup callback returns), then usb_ep_set_halt() may be 332 * used on ep0 to trigger protocol stalls. 333 * 334 * For periodic endpoints, like interrupt or isochronous ones, the usb host 335 * arranges to poll once per interval, and the gadget driver usually will 336 * have queued some data to transfer at that time. 337 * 338 * Returns zero, or a negative error code. Endpoints that are not enabled 339 * report errors; errors will also be 340 * reported when the usb peripheral is disconnected. 341 */ 342static inline int usb_ep_queue(struct usb_ep *ep, 343 struct usb_request *req, gfp_t gfp_flags) 344{ 345 return ep->ops->queue(ep, req, gfp_flags); 346} 347 348/** 349 * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint 350 * @ep:the endpoint associated with the request 351 * @req:the request being canceled 352 * 353 * if the request is still active on the endpoint, it is dequeued and its 354 * completion routine is called (with status -ECONNRESET); else a negative 355 * error code is returned. 356 * 357 * note that some hardware can't clear out write fifos (to unlink the request 358 * at the head of the queue) except as part of disconnecting from usb. such 359 * restrictions prevent drivers from supporting configuration changes, 360 * even to configuration zero (a "chapter 9" requirement). 361 */ 362static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) 363{ 364 return ep->ops->dequeue(ep, req); 365} 366 367/** 368 * usb_ep_set_halt - sets the endpoint halt feature. 369 * @ep: the non-isochronous endpoint being stalled 370 * 371 * Use this to stall an endpoint, perhaps as an error report. 372 * Except for control endpoints, 373 * the endpoint stays halted (will not stream any data) until the host 374 * clears this feature; drivers may need to empty the endpoint's request 375 * queue first, to make sure no inappropriate transfers happen. 376 * 377 * Note that while an endpoint CLEAR_FEATURE will be invisible to the 378 * gadget driver, a SET_INTERFACE will not be. To reset endpoints for the 379 * current altsetting, see usb_ep_clear_halt(). When switching altsettings, 380 * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints. 381 * 382 * Returns zero, or a negative error code. On success, this call sets 383 * underlying hardware state that blocks data transfers. 384 * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any 385 * transfer requests are still queued, or if the controller hardware 386 * (usually a FIFO) still holds bytes that the host hasn't collected. 387 */ 388static inline int usb_ep_set_halt(struct usb_ep *ep) 389{ 390 return ep->ops->set_halt(ep, 1); 391} 392 393/** 394 * usb_ep_clear_halt - clears endpoint halt, and resets toggle 395 * @ep:the bulk or interrupt endpoint being reset 396 * 397 * Use this when responding to the standard usb "set interface" request, 398 * for endpoints that aren't reconfigured, after clearing any other state 399 * in the endpoint's i/o queue. 400 * 401 * Returns zero, or a negative error code. On success, this call clears 402 * the underlying hardware state reflecting endpoint halt and data toggle. 403 * Note that some hardware can't support this request (like pxa2xx_udc), 404 * and accordingly can't correctly implement interface altsettings. 405 */ 406static inline int usb_ep_clear_halt(struct usb_ep *ep) 407{ 408 return ep->ops->set_halt(ep, 0); 409} 410 411/** 412 * usb_ep_fifo_status - returns number of bytes in fifo, or error 413 * @ep: the endpoint whose fifo status is being checked. 414 * 415 * FIFO endpoints may have "unclaimed data" in them in certain cases, 416 * such as after aborted transfers. Hosts may not have collected all 417 * the IN data written by the gadget driver (and reported by a request 418 * completion). The gadget driver may not have collected all the data 419 * written OUT to it by the host. Drivers that need precise handling for 420 * fault reporting or recovery may need to use this call. 421 * 422 * This returns the number of such bytes in the fifo, or a negative 423 * errno if the endpoint doesn't use a FIFO or doesn't support such 424 * precise handling. 425 */ 426static inline int usb_ep_fifo_status(struct usb_ep *ep) 427{ 428 if (ep->ops->fifo_status) 429 return ep->ops->fifo_status(ep); 430 else 431 return -EOPNOTSUPP; 432} 433 434/** 435 * usb_ep_fifo_flush - flushes contents of a fifo 436 * @ep: the endpoint whose fifo is being flushed. 437 * 438 * This call may be used to flush the "unclaimed data" that may exist in 439 * an endpoint fifo after abnormal transaction terminations. The call 440 * must never be used except when endpoint is not being used for any 441 * protocol translation. 442 */ 443static inline void usb_ep_fifo_flush(struct usb_ep *ep) 444{ 445 if (ep->ops->fifo_flush) 446 ep->ops->fifo_flush(ep); 447} 448 449 450/*-------------------------------------------------------------------------*/ 451 452struct usb_dcd_config_params { 453 __u8 bU1devExitLat; /* U1 Device exit Latency */ 454 __le16 bU2DevExitLat; /* U2 Device exit Latency */ 455}; 456 457struct usb_gadget; 458struct usb_gadget_driver; 459 460/* the rest of the api to the controller hardware: device operations, 461 * which don't involve endpoints (or i/o). 462 */ 463struct usb_gadget_ops { 464 int (*get_frame)(struct usb_gadget *); 465 int (*wakeup)(struct usb_gadget *); 466 int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); 467 int (*vbus_session) (struct usb_gadget *, int is_active); 468 int (*vbus_draw) (struct usb_gadget *, unsigned mA); 469 int (*pullup) (struct usb_gadget *, int is_on); 470 int (*ioctl)(struct usb_gadget *, 471 unsigned code, unsigned long param); 472 void (*get_config_params)(struct usb_dcd_config_params *); 473 int (*udc_start)(struct usb_gadget *, 474 struct usb_gadget_driver *); 475 int (*udc_stop)(struct usb_gadget *); 476 struct usb_ep *(*match_ep)(struct usb_gadget *, 477 struct usb_endpoint_descriptor *, 478 struct usb_ss_ep_comp_descriptor *); 479 int (*ep_conf)(struct usb_gadget *, 480 struct usb_ep *, 481 struct usb_endpoint_descriptor *); 482 void (*udc_set_speed)(struct usb_gadget *gadget, 483 enum usb_device_speed); 484}; 485 486/** 487 * struct usb_gadget - represents a usb slave device 488 * @ops: Function pointers used to access hardware-specific operations. 489 * @ep0: Endpoint zero, used when reading or writing responses to 490 * driver setup() requests 491 * @ep_list: List of other endpoints supported by the device. 492 * @speed: Speed of current connection to USB host. 493 * @max_speed: Maximal speed the UDC can handle. UDC must support this 494 * and all slower speeds. 495 * @is_dualspeed: true if the controller supports both high and full speed 496 * operation. If it does, the gadget driver must also support both. 497 * @is_otg: true if the USB device port uses a Mini-AB jack, so that the 498 * gadget driver must provide a USB OTG descriptor. 499 * @is_a_peripheral: false unless is_otg, the "A" end of a USB cable 500 * is in the Mini-AB jack, and HNP has been used to switch roles 501 * so that the "A" device currently acts as A-Peripheral, not A-Host. 502 * @a_hnp_support: OTG device feature flag, indicating that the A-Host 503 * supports HNP at this port. 504 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host 505 * only supports HNP on a different root port. 506 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host 507 * enabled HNP support. 508 * @name: Identifies the controller hardware type. Used in diagnostics 509 * and sometimes configuration. 510 * @dev: Driver model state for this abstract device. 511 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to 512 * MaxPacketSize. 513 * 514 * Gadgets have a mostly-portable "gadget driver" implementing device 515 * functions, handling all usb configurations and interfaces. Gadget 516 * drivers talk to hardware-specific code indirectly, through ops vectors. 517 * That insulates the gadget driver from hardware details, and packages 518 * the hardware endpoints through generic i/o queues. The "usb_gadget" 519 * and "usb_ep" interfaces provide that insulation from the hardware. 520 * 521 * Except for the driver data, all fields in this structure are 522 * read-only to the gadget driver. That driver data is part of the 523 * "driver model" infrastructure in 2.6 (and later) kernels, and for 524 * earlier systems is grouped in a similar structure that's not known 525 * to the rest of the kernel. 526 * 527 * Values of the three OTG device feature flags are updated before the 528 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before 529 * driver suspend() calls. They are valid only when is_otg, and when the 530 * device is acting as a B-Peripheral (so is_a_peripheral is false). 531 */ 532struct usb_gadget { 533 /* readonly to gadget driver */ 534 const struct usb_gadget_ops *ops; 535 struct usb_ep *ep0; 536 struct list_head ep_list; /* of usb_ep */ 537 enum usb_device_speed speed; 538 enum usb_device_speed max_speed; 539 enum usb_device_state state; 540 unsigned is_dualspeed:1; 541 unsigned is_otg:1; 542 unsigned is_a_peripheral:1; 543 unsigned b_hnp_enable:1; 544 unsigned a_hnp_support:1; 545 unsigned a_alt_hnp_support:1; 546 const char *name; 547 struct device dev; 548 unsigned quirk_ep_out_aligned_size:1; 549}; 550 551static inline void set_gadget_data(struct usb_gadget *gadget, void *data) 552{ 553 gadget->dev.driver_data = data; 554} 555 556static inline void *get_gadget_data(struct usb_gadget *gadget) 557{ 558 return gadget->dev.driver_data; 559} 560 561static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) 562{ 563 return container_of(dev, struct usb_gadget, dev); 564} 565 566/* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ 567#define gadget_for_each_ep(tmp, gadget) \ 568 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) 569 570 571/** 572 * gadget_is_dualspeed - return true iff the hardware handles high speed 573 * @g: controller that might support both high and full speeds 574 */ 575static inline int gadget_is_dualspeed(struct usb_gadget *g) 576{ 577#ifdef CONFIG_USB_GADGET_DUALSPEED 578 /* runtime test would check "g->is_dualspeed" ... that might be 579 * useful to work around hardware bugs, but is mostly pointless 580 */ 581 return 1; 582#else 583 return 0; 584#endif 585} 586 587/** 588 * gadget_is_otg - return true iff the hardware is OTG-ready 589 * @g: controller that might have a Mini-AB connector 590 * 591 * This is a runtime test, since kernels with a USB-OTG stack sometimes 592 * run on boards which only have a Mini-B (or Mini-A) connector. 593 */ 594static inline int gadget_is_otg(struct usb_gadget *g) 595{ 596#ifdef CONFIG_USB_OTG 597 return g->is_otg; 598#else 599 return 0; 600#endif 601} 602 603/** 604 * gadget_is_superspeed() - return true if the hardware handles superspeed 605 * @g: controller that might support superspeed 606 */ 607static inline int gadget_is_superspeed(struct usb_gadget *g) 608{ 609 return g->max_speed >= USB_SPEED_SUPER; 610} 611 612/** 613 * usb_gadget_frame_number - returns the current frame number 614 * @gadget: controller that reports the frame number 615 * 616 * Returns the usb frame number, normally eleven bits from a SOF packet, 617 * or negative errno if this device doesn't support this capability. 618 */ 619static inline int usb_gadget_frame_number(struct usb_gadget *gadget) 620{ 621 return gadget->ops->get_frame(gadget); 622} 623 624/** 625 * usb_gadget_wakeup - tries to wake up the host connected to this gadget 626 * @gadget: controller used to wake up the host 627 * 628 * Returns zero on success, else negative error code if the hardware 629 * doesn't support such attempts, or its support has not been enabled 630 * by the usb host. Drivers must return device descriptors that report 631 * their ability to support this, or hosts won't enable it. 632 * 633 * This may also try to use SRP to wake the host and start enumeration, 634 * even if OTG isn't otherwise in use. OTG devices may also start 635 * remote wakeup even when hosts don't explicitly enable it. 636 */ 637static inline int usb_gadget_wakeup(struct usb_gadget *gadget) 638{ 639 if (!gadget->ops->wakeup) 640 return -EOPNOTSUPP; 641 return gadget->ops->wakeup(gadget); 642} 643 644/** 645 * usb_gadget_set_selfpowered - sets the device selfpowered feature. 646 * @gadget:the device being declared as self-powered 647 * 648 * this affects the device status reported by the hardware driver 649 * to reflect that it now has a local power supply. 650 * 651 * returns zero on success, else negative errno. 652 */ 653static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) 654{ 655 if (!gadget->ops->set_selfpowered) 656 return -EOPNOTSUPP; 657 return gadget->ops->set_selfpowered(gadget, 1); 658} 659 660/** 661 * usb_gadget_clear_selfpowered - clear the device selfpowered feature. 662 * @gadget:the device being declared as bus-powered 663 * 664 * this affects the device status reported by the hardware driver. 665 * some hardware may not support bus-powered operation, in which 666 * case this feature's value can never change. 667 * 668 * returns zero on success, else negative errno. 669 */ 670static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) 671{ 672 if (!gadget->ops->set_selfpowered) 673 return -EOPNOTSUPP; 674 return gadget->ops->set_selfpowered(gadget, 0); 675} 676 677/** 678 * usb_gadget_vbus_connect - Notify controller that VBUS is powered 679 * @gadget:The device which now has VBUS power. 680 * 681 * This call is used by a driver for an external transceiver (or GPIO) 682 * that detects a VBUS power session starting. Common responses include 683 * resuming the controller, activating the D+ (or D-) pullup to let the 684 * host detect that a USB device is attached, and starting to draw power 685 * (8mA or possibly more, especially after SET_CONFIGURATION). 686 * 687 * Returns zero on success, else negative errno. 688 */ 689static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) 690{ 691 if (!gadget->ops->vbus_session) 692 return -EOPNOTSUPP; 693 return gadget->ops->vbus_session(gadget, 1); 694} 695 696/** 697 * usb_gadget_vbus_draw - constrain controller's VBUS power usage 698 * @gadget:The device whose VBUS usage is being described 699 * @mA:How much current to draw, in milliAmperes. This should be twice 700 * the value listed in the configuration descriptor bMaxPower field. 701 * 702 * This call is used by gadget drivers during SET_CONFIGURATION calls, 703 * reporting how much power the device may consume. For example, this 704 * could affect how quickly batteries are recharged. 705 * 706 * Returns zero on success, else negative errno. 707 */ 708static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) 709{ 710 if (!gadget->ops->vbus_draw) 711 return -EOPNOTSUPP; 712 return gadget->ops->vbus_draw(gadget, mA); 713} 714 715/** 716 * usb_gadget_vbus_disconnect - notify controller about VBUS session end 717 * @gadget:the device whose VBUS supply is being described 718 * 719 * This call is used by a driver for an external transceiver (or GPIO) 720 * that detects a VBUS power session ending. Common responses include 721 * reversing everything done in usb_gadget_vbus_connect(). 722 * 723 * Returns zero on success, else negative errno. 724 */ 725static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) 726{ 727 if (!gadget->ops->vbus_session) 728 return -EOPNOTSUPP; 729 return gadget->ops->vbus_session(gadget, 0); 730} 731 732/** 733 * usb_gadget_connect - software-controlled connect to USB host 734 * @gadget:the peripheral being connected 735 * 736 * Enables the D+ (or potentially D-) pullup. The host will start 737 * enumerating this gadget when the pullup is active and a VBUS session 738 * is active (the link is powered). This pullup is always enabled unless 739 * usb_gadget_disconnect() has been used to disable it. 740 * 741 * Returns zero on success, else negative errno. 742 */ 743static inline int usb_gadget_connect(struct usb_gadget *gadget) 744{ 745 if (!gadget->ops->pullup) 746 return -EOPNOTSUPP; 747 return gadget->ops->pullup(gadget, 1); 748} 749 750/** 751 * usb_gadget_disconnect - software-controlled disconnect from USB host 752 * @gadget:the peripheral being disconnected 753 * 754 * Disables the D+ (or potentially D-) pullup, which the host may see 755 * as a disconnect (when a VBUS session is active). Not all systems 756 * support software pullup controls. 757 * 758 * This routine may be used during the gadget driver bind() call to prevent 759 * the peripheral from ever being visible to the USB host, unless later 760 * usb_gadget_connect() is called. For example, user mode components may 761 * need to be activated before the system can talk to hosts. 762 * 763 * Returns zero on success, else negative errno. 764 */ 765static inline int usb_gadget_disconnect(struct usb_gadget *gadget) 766{ 767 if (!gadget->ops->pullup) 768 return -EOPNOTSUPP; 769 return gadget->ops->pullup(gadget, 0); 770} 771 772 773/*-------------------------------------------------------------------------*/ 774 775/** 776 * struct usb_gadget_driver - driver for usb 'slave' devices 777 * @function: String describing the gadget's function 778 * @speed: Highest speed the driver handles. 779 * @bind: Invoked when the driver is bound to a gadget, usually 780 * after registering the driver. 781 * At that point, ep0 is fully initialized, and ep_list holds 782 * the currently-available endpoints. 783 * Called in a context that permits sleeping. 784 * @setup: Invoked for ep0 control requests that aren't handled by 785 * the hardware level driver. Most calls must be handled by 786 * the gadget driver, including descriptor and configuration 787 * management. The 16 bit members of the setup data are in 788 * USB byte order. Called in_interrupt; this may not sleep. Driver 789 * queues a response to ep0, or returns negative to stall. 790 * @disconnect: Invoked after all transfers have been stopped, 791 * when the host is disconnected. May be called in_interrupt; this 792 * may not sleep. Some devices can't detect disconnect, so this might 793 * not be called except as part of controller shutdown. 794 * @unbind: Invoked when the driver is unbound from a gadget, 795 * usually from rmmod (after a disconnect is reported). 796 * Called in a context that permits sleeping. 797 * @suspend: Invoked on USB suspend. May be called in_interrupt. 798 * @resume: Invoked on USB resume. May be called in_interrupt. 799 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers 800 * and should be called in_interrupt. 801 * 802 * Devices are disabled till a gadget driver successfully bind()s, which 803 * means the driver will handle setup() requests needed to enumerate (and 804 * meet "chapter 9" requirements) then do some useful work. 805 * 806 * If gadget->is_otg is true, the gadget driver must provide an OTG 807 * descriptor during enumeration, or else fail the bind() call. In such 808 * cases, no USB traffic may flow until both bind() returns without 809 * having called usb_gadget_disconnect(), and the USB host stack has 810 * initialized. 811 * 812 * Drivers use hardware-specific knowledge to configure the usb hardware. 813 * endpoint addressing is only one of several hardware characteristics that 814 * are in descriptors the ep0 implementation returns from setup() calls. 815 * 816 * Except for ep0 implementation, most driver code shouldn't need change to 817 * run on top of different usb controllers. It'll use endpoints set up by 818 * that ep0 implementation. 819 * 820 * The usb controller driver handles a few standard usb requests. Those 821 * include set_address, and feature flags for devices, interfaces, and 822 * endpoints (the get_status, set_feature, and clear_feature requests). 823 * 824 * Accordingly, the driver's setup() callback must always implement all 825 * get_descriptor requests, returning at least a device descriptor and 826 * a configuration descriptor. Drivers must make sure the endpoint 827 * descriptors match any hardware constraints. Some hardware also constrains 828 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). 829 * 830 * The driver's setup() callback must also implement set_configuration, 831 * and should also implement set_interface, get_configuration, and 832 * get_interface. Setting a configuration (or interface) is where 833 * endpoints should be activated or (config 0) shut down. 834 * 835 * (Note that only the default control endpoint is supported. Neither 836 * hosts nor devices generally support control traffic except to ep0.) 837 * 838 * Most devices will ignore USB suspend/resume operations, and so will 839 * not provide those callbacks. However, some may need to change modes 840 * when the host is not longer directing those activities. For example, 841 * local controls (buttons, dials, etc) may need to be re-enabled since 842 * the (remote) host can't do that any longer; or an error state might 843 * be cleared, to make the device behave identically whether or not 844 * power is maintained. 845 */ 846struct usb_gadget_driver { 847 char *function; 848 enum usb_device_speed speed; 849 int (*bind)(struct usb_gadget *); 850 void (*unbind)(struct usb_gadget *); 851 int (*setup)(struct usb_gadget *, 852 const struct usb_ctrlrequest *); 853 void (*disconnect)(struct usb_gadget *); 854 void (*suspend)(struct usb_gadget *); 855 void (*resume)(struct usb_gadget *); 856 void (*reset)(struct usb_gadget *); 857}; 858 859 860/*-------------------------------------------------------------------------*/ 861 862/* driver modules register and unregister, as usual. 863 * these calls must be made in a context that can sleep. 864 * 865 * these will usually be implemented directly by the hardware-dependent 866 * usb bus interface driver, which will only support a single driver. 867 */ 868 869/** 870 * usb_gadget_register_driver - register a gadget driver 871 * @driver:the driver being registered 872 * 873 * Call this in your gadget driver's module initialization function, 874 * to tell the underlying usb controller driver about your driver. 875 * The driver's bind() function will be called to bind it to a 876 * gadget before this registration call returns. It's expected that 877 * the bind() functions will be in init sections. 878 * This function must be called in a context that can sleep. 879 */ 880int usb_gadget_register_driver(struct usb_gadget_driver *driver); 881 882/** 883 * usb_gadget_unregister_driver - unregister a gadget driver 884 * @driver:the driver being unregistered 885 * 886 * Call this in your gadget driver's module cleanup function, 887 * to tell the underlying usb controller that your driver is 888 * going away. If the controller is connected to a USB host, 889 * it will first disconnect(). The driver is also requested 890 * to unbind() and clean up any device state, before this procedure 891 * finally returns. It's expected that the unbind() functions 892 * will in in exit sections, so may not be linked in some kernels. 893 * This function must be called in a context that can sleep. 894 */ 895int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); 896 897int usb_add_gadget_udc_release(struct device *parent, 898 struct usb_gadget *gadget, void (*release)(struct device *dev)); 899int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); 900void usb_del_gadget_udc(struct usb_gadget *gadget); 901/*-------------------------------------------------------------------------*/ 902 903/* utility to simplify dealing with string descriptors */ 904 905/** 906 * struct usb_gadget_strings - a set of USB strings in a given language 907 * @language:identifies the strings' language (0x0409 for en-us) 908 * @strings:array of strings with their ids 909 * 910 * If you're using usb_gadget_get_string(), use this to wrap all the 911 * strings for a given language. 912 */ 913struct usb_gadget_strings { 914 u16 language; /* 0x0409 for en-us */ 915 struct usb_string *strings; 916}; 917 918/* put descriptor for string with that id into buf (buflen >= 256) */ 919int usb_gadget_get_string(struct usb_gadget_strings *table, int id, u8 *buf); 920 921/*-------------------------------------------------------------------------*/ 922 923/* utility to simplify managing config descriptors */ 924 925/* write vector of descriptors into buffer */ 926int usb_descriptor_fillbuf(void *, unsigned, 927 const struct usb_descriptor_header **); 928 929/* build config descriptor from single descriptor vector */ 930int usb_gadget_config_buf(const struct usb_config_descriptor *config, 931 void *buf, unsigned buflen, const struct usb_descriptor_header **desc); 932 933/*-------------------------------------------------------------------------*/ 934/* utility to simplify map/unmap of usb_requests to/from DMA */ 935 936extern int usb_gadget_map_request(struct usb_gadget *gadget, 937 struct usb_request *req, int is_in); 938 939extern void usb_gadget_unmap_request(struct usb_gadget *gadget, 940 struct usb_request *req, int is_in); 941 942/*-------------------------------------------------------------------------*/ 943 944/* utility to set gadget state properly */ 945 946extern void usb_gadget_set_state(struct usb_gadget *gadget, 947 enum usb_device_state state); 948 949/*-------------------------------------------------------------------------*/ 950 951/* utility to tell udc core that the bus reset occurs */ 952extern void usb_gadget_udc_reset(struct usb_gadget *gadget, 953 struct usb_gadget_driver *driver); 954 955/*-------------------------------------------------------------------------*/ 956 957/* utility to give requests back to the gadget layer */ 958 959extern void usb_gadget_giveback_request(struct usb_ep *ep, 960 struct usb_request *req); 961 962/*-------------------------------------------------------------------------*/ 963 964/* utility wrapping a simple endpoint selection policy */ 965 966extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, 967 struct usb_endpoint_descriptor *); 968 969extern void usb_ep_autoconfig_reset(struct usb_gadget *); 970 971extern int usb_gadget_handle_interrupts(int index); 972 973#if CONFIG_IS_ENABLED(DM_USB_GADGET) 974int usb_gadget_initialize(int index); 975int usb_gadget_release(int index); 976int dm_usb_gadget_handle_interrupts(struct udevice *dev); 977#else 978#include <usb.h> 979static inline int usb_gadget_initialize(int index) 980{ 981 return board_usb_init(index, USB_INIT_DEVICE); 982} 983 984static inline int usb_gadget_release(int index) 985{ 986 return board_usb_cleanup(index, USB_INIT_DEVICE); 987} 988#endif 989 990#endif /* __LINUX_USB_GADGET_H */ 991