1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * <linux/usb/gadget.h> 4 * 5 * We call the USB code inside a Linux-based peripheral device a "gadget" 6 * driver, except for the hardware-specific bus glue. One USB host can 7 * master many USB gadgets, but the gadgets are only slaved to one host. 8 * 9 * 10 * (C) Copyright 2002-2004 by David Brownell 11 * All Rights Reserved. 12 * 13 * This software is licensed under the GNU GPL version 2. 14 */ 15 16 #ifndef __LINUX_USB_GADGET_H 17 #define __LINUX_USB_GADGET_H 18 19 #include <linux/device.h> 20 #include <linux/errno.h> 21 #include <linux/init.h> 22 #include <linux/list.h> 23 #include <linux/slab.h> 24 #include <linux/scatterlist.h> 25 #include <linux/types.h> 26 #include <linux/workqueue.h> 27 #include <linux/usb/ch9.h> 28 29 #define UDC_TRACE_STR_MAX 512 30 31 struct usb_ep; 32 33 /** 34 * struct usb_request - describes one i/o request 35 * @buf: Buffer used for data. Always provide this; some controllers 36 * only use PIO, or don't use DMA for some endpoints. 37 * @dma: DMA address corresponding to 'buf'. If you don't set this 38 * field, and the usb controller needs one, it is responsible 39 * for mapping and unmapping the buffer. 40 * @sg: a scatterlist for SG-capable controllers. 41 * @num_sgs: number of SG entries 42 * @num_mapped_sgs: number of SG entries mapped to DMA (internal) 43 * @length: Length of that data 44 * @stream_id: The stream id, when USB3.0 bulk streams are being used 45 * @no_interrupt: If true, hints that no completion irq is needed. 46 * Helpful sometimes with deep request queues that are handled 47 * directly by DMA controllers. 48 * @zero: If true, when writing data, makes the last packet be "short" 49 * by adding a zero length packet as needed; 50 * @short_not_ok: When reading data, makes short packets be 51 * treated as errors (queue stops advancing till cleanup). 52 * @dma_mapped: Indicates if request has been mapped to DMA (internal) 53 * @complete: Function called when request completes, so this request and 54 * its buffer may be re-used. The function will always be called with 55 * interrupts disabled, and it must not sleep. 56 * Reads terminate with a short packet, or when the buffer fills, 57 * whichever comes first. When writes terminate, some data bytes 58 * will usually still be in flight (often in a hardware fifo). 59 * Errors (for reads or writes) stop the queue from advancing 60 * until the completion function returns, so that any transfers 61 * invalidated by the error may first be dequeued. 62 * @context: For use by the completion callback 63 * @list: For use by the gadget driver. 64 * @frame_number: Reports the interval number in (micro)frame in which the 65 * isochronous transfer was transmitted or received. 66 * @status: Reports completion code, zero or a negative errno. 67 * Normally, faults block the transfer queue from advancing until 68 * the completion callback returns. 69 * Code "-ESHUTDOWN" indicates completion caused by device disconnect, 70 * or when the driver disabled the endpoint. 71 * @actual: Reports bytes transferred to/from the buffer. For reads (OUT 72 * transfers) this may be less than the requested length. If the 73 * short_not_ok flag is set, short reads are treated as errors 74 * even when status otherwise indicates successful completion. 75 * Note that for writes (IN transfers) some data bytes may still 76 * reside in a device-side FIFO when the request is reported as 77 * complete. 78 * 79 * These are allocated/freed through the endpoint they're used with. The 80 * hardware's driver can add extra per-request data to the memory it returns, 81 * which often avoids separate memory allocations (potential failures), 82 * later when the request is queued. 83 * 84 * Request flags affect request handling, such as whether a zero length 85 * packet is written (the "zero" flag), whether a short read should be 86 * treated as an error (blocking request queue advance, the "short_not_ok" 87 * flag), or hinting that an interrupt is not required (the "no_interrupt" 88 * flag, for use with deep request queues). 89 * 90 * Bulk endpoints can use any size buffers, and can also be used for interrupt 91 * transfers. interrupt-only endpoints can be much less functional. 92 * 93 * NOTE: this is analogous to 'struct urb' on the host side, except that 94 * it's thinner and promotes more pre-allocation. 95 */ 96 97 struct usb_request { 98 void *buf; 99 unsigned length; 100 dma_addr_t dma; 101 102 struct scatterlist *sg; 103 unsigned num_sgs; 104 unsigned num_mapped_sgs; 105 106 unsigned stream_id:16; 107 unsigned no_interrupt:1; 108 unsigned zero:1; 109 unsigned short_not_ok:1; 110 unsigned dma_mapped:1; 111 112 void (*complete)(struct usb_ep *ep, 113 struct usb_request *req); 114 void *context; 115 struct list_head list; 116 117 unsigned frame_number; /* ISO ONLY */ 118 119 int status; 120 unsigned actual; 121 }; 122 123 /*-------------------------------------------------------------------------*/ 124 125 /* endpoint-specific parts of the api to the usb controller hardware. 126 * unlike the urb model, (de)multiplexing layers are not required. 127 * (so this api could slash overhead if used on the host side...) 128 * 129 * note that device side usb controllers commonly differ in how many 130 * endpoints they support, as well as their capabilities. 131 */ 132 struct usb_ep_ops { 133 int (*enable) (struct usb_ep *ep, 134 const struct usb_endpoint_descriptor *desc); 135 int (*disable) (struct usb_ep *ep); 136 void (*dispose) (struct usb_ep *ep); 137 138 struct usb_request *(*alloc_request) (struct usb_ep *ep, 139 gfp_t gfp_flags); 140 void (*free_request) (struct usb_ep *ep, struct usb_request *req); 141 142 int (*queue) (struct usb_ep *ep, struct usb_request *req, 143 gfp_t gfp_flags); 144 int (*dequeue) (struct usb_ep *ep, struct usb_request *req); 145 146 int (*set_halt) (struct usb_ep *ep, int value); 147 int (*set_wedge) (struct usb_ep *ep); 148 149 int (*fifo_status) (struct usb_ep *ep); 150 void (*fifo_flush) (struct usb_ep *ep); 151 }; 152 153 /** 154 * struct usb_ep_caps - endpoint capabilities description 155 * @type_control:Endpoint supports control type (reserved for ep0). 156 * @type_iso:Endpoint supports isochronous transfers. 157 * @type_bulk:Endpoint supports bulk transfers. 158 * @type_int:Endpoint supports interrupt transfers. 159 * @dir_in:Endpoint supports IN direction. 160 * @dir_out:Endpoint supports OUT direction. 161 */ 162 struct usb_ep_caps { 163 unsigned type_control:1; 164 unsigned type_iso:1; 165 unsigned type_bulk:1; 166 unsigned type_int:1; 167 unsigned dir_in:1; 168 unsigned dir_out:1; 169 }; 170 171 #define USB_EP_CAPS_TYPE_CONTROL 0x01 172 #define USB_EP_CAPS_TYPE_ISO 0x02 173 #define USB_EP_CAPS_TYPE_BULK 0x04 174 #define USB_EP_CAPS_TYPE_INT 0x08 175 #define USB_EP_CAPS_TYPE_ALL \ 176 (USB_EP_CAPS_TYPE_ISO | USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT) 177 #define USB_EP_CAPS_DIR_IN 0x01 178 #define USB_EP_CAPS_DIR_OUT 0x02 179 #define USB_EP_CAPS_DIR_ALL (USB_EP_CAPS_DIR_IN | USB_EP_CAPS_DIR_OUT) 180 181 #define USB_EP_CAPS(_type, _dir) \ 182 { \ 183 .type_control = !!(_type & USB_EP_CAPS_TYPE_CONTROL), \ 184 .type_iso = !!(_type & USB_EP_CAPS_TYPE_ISO), \ 185 .type_bulk = !!(_type & USB_EP_CAPS_TYPE_BULK), \ 186 .type_int = !!(_type & USB_EP_CAPS_TYPE_INT), \ 187 .dir_in = !!(_dir & USB_EP_CAPS_DIR_IN), \ 188 .dir_out = !!(_dir & USB_EP_CAPS_DIR_OUT), \ 189 } 190 191 /** 192 * struct usb_ep - device side representation of USB endpoint 193 * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk" 194 * @ops: Function pointers used to access hardware-specific operations. 195 * @ep_list:the gadget's ep_list holds all of its endpoints 196 * @caps:The structure describing types and directions supported by endoint. 197 * @enabled: The current endpoint enabled/disabled state. 198 * @claimed: True if this endpoint is claimed by a function. 199 * @maxpacket:The maximum packet size used on this endpoint. The initial 200 * value can sometimes be reduced (hardware allowing), according to 201 * the endpoint descriptor used to configure the endpoint. 202 * @maxpacket_limit:The maximum packet size value which can be handled by this 203 * endpoint. It's set once by UDC driver when endpoint is initialized, and 204 * should not be changed. Should not be confused with maxpacket. 205 * @max_streams: The maximum number of streams supported 206 * by this EP (0 - 16, actual number is 2^n) 207 * @mult: multiplier, 'mult' value for SS Isoc EPs 208 * @maxburst: the maximum number of bursts supported by this EP (for usb3) 209 * @driver_data:for use by the gadget driver. 210 * @address: used to identify the endpoint when finding descriptor that 211 * matches connection speed 212 * @desc: endpoint descriptor. This pointer is set before the endpoint is 213 * enabled and remains valid until the endpoint is disabled. 214 * @comp_desc: In case of SuperSpeed support, this is the endpoint companion 215 * descriptor that is used to configure the endpoint 216 * 217 * the bus controller driver lists all the general purpose endpoints in 218 * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, 219 * and is accessed only in response to a driver setup() callback. 220 */ 221 222 struct usb_ep { 223 void *driver_data; 224 225 const char *name; 226 const struct usb_ep_ops *ops; 227 struct list_head ep_list; 228 struct usb_ep_caps caps; 229 bool claimed; 230 bool enabled; 231 unsigned maxpacket:16; 232 unsigned maxpacket_limit:16; 233 unsigned max_streams:16; 234 unsigned mult:2; 235 unsigned maxburst:5; 236 u8 address; 237 const struct usb_endpoint_descriptor *desc; 238 const struct usb_ss_ep_comp_descriptor *comp_desc; 239 }; 240 241 /*-------------------------------------------------------------------------*/ 242 243 #if IS_ENABLED(CONFIG_USB_GADGET) 244 void usb_ep_set_maxpacket_limit(struct usb_ep *ep, unsigned maxpacket_limit); 245 int usb_ep_enable(struct usb_ep *ep); 246 int usb_ep_disable(struct usb_ep *ep); 247 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags); 248 void usb_ep_free_request(struct usb_ep *ep, struct usb_request *req); 249 int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags); 250 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req); 251 int usb_ep_set_halt(struct usb_ep *ep); 252 int usb_ep_clear_halt(struct usb_ep *ep); 253 int usb_ep_set_wedge(struct usb_ep *ep); 254 int usb_ep_fifo_status(struct usb_ep *ep); 255 void usb_ep_fifo_flush(struct usb_ep *ep); 256 #else 257 static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep, 258 unsigned maxpacket_limit) 259 { } 260 static inline int usb_ep_enable(struct usb_ep *ep) 261 { return 0; } 262 static inline int usb_ep_disable(struct usb_ep *ep) 263 { return 0; } 264 static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, 265 gfp_t gfp_flags) 266 { return NULL; } 267 static inline void usb_ep_free_request(struct usb_ep *ep, 268 struct usb_request *req) 269 { } 270 static inline int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, 271 gfp_t gfp_flags) 272 { return 0; } 273 static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) 274 { return 0; } 275 static inline int usb_ep_set_halt(struct usb_ep *ep) 276 { return 0; } 277 static inline int usb_ep_clear_halt(struct usb_ep *ep) 278 { return 0; } 279 static inline int usb_ep_set_wedge(struct usb_ep *ep) 280 { return 0; } 281 static inline int usb_ep_fifo_status(struct usb_ep *ep) 282 { return 0; } 283 static inline void usb_ep_fifo_flush(struct usb_ep *ep) 284 { } 285 #endif /* USB_GADGET */ 286 287 /*-------------------------------------------------------------------------*/ 288 289 struct usb_dcd_config_params { 290 __u8 bU1devExitLat; /* U1 Device exit Latency */ 291 #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */ 292 __le16 bU2DevExitLat; /* U2 Device exit Latency */ 293 #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */ 294 }; 295 296 297 struct usb_gadget; 298 struct usb_gadget_driver; 299 struct usb_udc; 300 301 /* the rest of the api to the controller hardware: device operations, 302 * which don't involve endpoints (or i/o). 303 */ 304 struct usb_gadget_ops { 305 int (*get_frame)(struct usb_gadget *); 306 int (*wakeup)(struct usb_gadget *); 307 int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); 308 int (*vbus_session) (struct usb_gadget *, int is_active); 309 int (*vbus_draw) (struct usb_gadget *, unsigned mA); 310 int (*pullup) (struct usb_gadget *, int is_on); 311 int (*ioctl)(struct usb_gadget *, 312 unsigned code, unsigned long param); 313 void (*get_config_params)(struct usb_dcd_config_params *); 314 int (*udc_start)(struct usb_gadget *, 315 struct usb_gadget_driver *); 316 int (*udc_stop)(struct usb_gadget *); 317 void (*udc_set_speed)(struct usb_gadget *, enum usb_device_speed); 318 struct usb_ep *(*match_ep)(struct usb_gadget *, 319 struct usb_endpoint_descriptor *, 320 struct usb_ss_ep_comp_descriptor *); 321 }; 322 323 /** 324 * struct usb_gadget - represents a usb slave device 325 * @work: (internal use) Workqueue to be used for sysfs_notify() 326 * @udc: struct usb_udc pointer for this gadget 327 * @ops: Function pointers used to access hardware-specific operations. 328 * @ep0: Endpoint zero, used when reading or writing responses to 329 * driver setup() requests 330 * @ep_list: List of other endpoints supported by the device. 331 * @speed: Speed of current connection to USB host. 332 * @max_speed: Maximal speed the UDC can handle. UDC must support this 333 * and all slower speeds. 334 * @state: the state we are now (attached, suspended, configured, etc) 335 * @name: Identifies the controller hardware type. Used in diagnostics 336 * and sometimes configuration. 337 * @dev: Driver model state for this abstract device. 338 * @isoch_delay: value from Set Isoch Delay request. Only valid on SS/SSP 339 * @out_epnum: last used out ep number 340 * @in_epnum: last used in ep number 341 * @mA: last set mA value 342 * @otg_caps: OTG capabilities of this gadget. 343 * @sg_supported: true if we can handle scatter-gather 344 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the 345 * gadget driver must provide a USB OTG descriptor. 346 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable 347 * is in the Mini-AB jack, and HNP has been used to switch roles 348 * so that the "A" device currently acts as A-Peripheral, not A-Host. 349 * @a_hnp_support: OTG device feature flag, indicating that the A-Host 350 * supports HNP at this port. 351 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host 352 * only supports HNP on a different root port. 353 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host 354 * enabled HNP support. 355 * @hnp_polling_support: OTG device feature flag, indicating if the OTG device 356 * in peripheral mode can support HNP polling. 357 * @host_request_flag: OTG device feature flag, indicating if A-Peripheral 358 * or B-Peripheral wants to take host role. 359 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to 360 * MaxPacketSize. 361 * @quirk_altset_not_supp: UDC controller doesn't support alt settings. 362 * @quirk_stall_not_supp: UDC controller doesn't support stalling. 363 * @quirk_zlp_not_supp: UDC controller doesn't support ZLP. 364 * @quirk_avoids_skb_reserve: udc/platform wants to avoid skb_reserve() in 365 * u_ether.c to improve performance. 366 * @is_selfpowered: if the gadget is self-powered. 367 * @deactivated: True if gadget is deactivated - in deactivated state it cannot 368 * be connected. 369 * @connected: True if gadget is connected. 370 * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag 371 * indicates that it supports LPM as per the LPM ECN & errata. 372 * 373 * Gadgets have a mostly-portable "gadget driver" implementing device 374 * functions, handling all usb configurations and interfaces. Gadget 375 * drivers talk to hardware-specific code indirectly, through ops vectors. 376 * That insulates the gadget driver from hardware details, and packages 377 * the hardware endpoints through generic i/o queues. The "usb_gadget" 378 * and "usb_ep" interfaces provide that insulation from the hardware. 379 * 380 * Except for the driver data, all fields in this structure are 381 * read-only to the gadget driver. That driver data is part of the 382 * "driver model" infrastructure in 2.6 (and later) kernels, and for 383 * earlier systems is grouped in a similar structure that's not known 384 * to the rest of the kernel. 385 * 386 * Values of the three OTG device feature flags are updated before the 387 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before 388 * driver suspend() calls. They are valid only when is_otg, and when the 389 * device is acting as a B-Peripheral (so is_a_peripheral is false). 390 */ 391 struct usb_gadget { 392 struct work_struct work; 393 struct usb_udc *udc; 394 /* readonly to gadget driver */ 395 const struct usb_gadget_ops *ops; 396 struct usb_ep *ep0; 397 struct list_head ep_list; /* of usb_ep */ 398 enum usb_device_speed speed; 399 enum usb_device_speed max_speed; 400 enum usb_device_state state; 401 const char *name; 402 struct device dev; 403 unsigned isoch_delay; 404 unsigned out_epnum; 405 unsigned in_epnum; 406 unsigned mA; 407 struct usb_otg_caps *otg_caps; 408 409 unsigned sg_supported:1; 410 unsigned is_otg:1; 411 unsigned is_a_peripheral:1; 412 unsigned b_hnp_enable:1; 413 unsigned a_hnp_support:1; 414 unsigned a_alt_hnp_support:1; 415 unsigned hnp_polling_support:1; 416 unsigned host_request_flag:1; 417 unsigned quirk_ep_out_aligned_size:1; 418 unsigned quirk_altset_not_supp:1; 419 unsigned quirk_stall_not_supp:1; 420 unsigned quirk_zlp_not_supp:1; 421 unsigned quirk_avoids_skb_reserve:1; 422 unsigned is_selfpowered:1; 423 unsigned deactivated:1; 424 unsigned connected:1; 425 unsigned lpm_capable:1; 426 }; 427 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work)) 428 429 static inline void set_gadget_data(struct usb_gadget *gadget, void *data) 430 { dev_set_drvdata(&gadget->dev, data); } 431 static inline void *get_gadget_data(struct usb_gadget *gadget) 432 { return dev_get_drvdata(&gadget->dev); } 433 static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) 434 { 435 return container_of(dev, struct usb_gadget, dev); 436 } 437 438 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ 439 #define gadget_for_each_ep(tmp, gadget) \ 440 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) 441 442 /** 443 * usb_ep_align - returns @len aligned to ep's maxpacketsize. 444 * @ep: the endpoint whose maxpacketsize is used to align @len 445 * @len: buffer size's length to align to @ep's maxpacketsize 446 * 447 * This helper is used to align buffer's size to an ep's maxpacketsize. 448 */ 449 static inline size_t usb_ep_align(struct usb_ep *ep, size_t len) 450 { 451 int max_packet_size = (size_t)usb_endpoint_maxp(ep->desc) & 0x7ff; 452 453 return round_up(len, max_packet_size); 454 } 455 456 /** 457 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget 458 * requires quirk_ep_out_aligned_size, otherwise returns len. 459 * @g: controller to check for quirk 460 * @ep: the endpoint whose maxpacketsize is used to align @len 461 * @len: buffer size's length to align to @ep's maxpacketsize 462 * 463 * This helper is used in case it's required for any reason to check and maybe 464 * align buffer's size to an ep's maxpacketsize. 465 */ 466 static inline size_t 467 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len) 468 { 469 return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len; 470 } 471 472 /** 473 * gadget_is_altset_supported - return true iff the hardware supports 474 * altsettings 475 * @g: controller to check for quirk 476 */ 477 static inline int gadget_is_altset_supported(struct usb_gadget *g) 478 { 479 return !g->quirk_altset_not_supp; 480 } 481 482 /** 483 * gadget_is_stall_supported - return true iff the hardware supports stalling 484 * @g: controller to check for quirk 485 */ 486 static inline int gadget_is_stall_supported(struct usb_gadget *g) 487 { 488 return !g->quirk_stall_not_supp; 489 } 490 491 /** 492 * gadget_is_zlp_supported - return true iff the hardware supports zlp 493 * @g: controller to check for quirk 494 */ 495 static inline int gadget_is_zlp_supported(struct usb_gadget *g) 496 { 497 return !g->quirk_zlp_not_supp; 498 } 499 500 /** 501 * gadget_avoids_skb_reserve - return true iff the hardware would like to avoid 502 * skb_reserve to improve performance. 503 * @g: controller to check for quirk 504 */ 505 static inline int gadget_avoids_skb_reserve(struct usb_gadget *g) 506 { 507 return g->quirk_avoids_skb_reserve; 508 } 509 510 /** 511 * gadget_is_dualspeed - return true iff the hardware handles high speed 512 * @g: controller that might support both high and full speeds 513 */ 514 static inline int gadget_is_dualspeed(struct usb_gadget *g) 515 { 516 return g->max_speed >= USB_SPEED_HIGH; 517 } 518 519 /** 520 * gadget_is_superspeed() - return true if the hardware handles superspeed 521 * @g: controller that might support superspeed 522 */ 523 static inline int gadget_is_superspeed(struct usb_gadget *g) 524 { 525 return g->max_speed >= USB_SPEED_SUPER; 526 } 527 528 /** 529 * gadget_is_superspeed_plus() - return true if the hardware handles 530 * superspeed plus 531 * @g: controller that might support superspeed plus 532 */ 533 static inline int gadget_is_superspeed_plus(struct usb_gadget *g) 534 { 535 return g->max_speed >= USB_SPEED_SUPER_PLUS; 536 } 537 538 /** 539 * gadget_is_otg - return true iff the hardware is OTG-ready 540 * @g: controller that might have a Mini-AB connector 541 * 542 * This is a runtime test, since kernels with a USB-OTG stack sometimes 543 * run on boards which only have a Mini-B (or Mini-A) connector. 544 */ 545 static inline int gadget_is_otg(struct usb_gadget *g) 546 { 547 #ifdef CONFIG_USB_OTG 548 return g->is_otg; 549 #else 550 return 0; 551 #endif 552 } 553 554 /*-------------------------------------------------------------------------*/ 555 556 #if IS_ENABLED(CONFIG_USB_GADGET) 557 int usb_gadget_frame_number(struct usb_gadget *gadget); 558 int usb_gadget_wakeup(struct usb_gadget *gadget); 559 int usb_gadget_set_selfpowered(struct usb_gadget *gadget); 560 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget); 561 int usb_gadget_vbus_connect(struct usb_gadget *gadget); 562 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA); 563 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget); 564 int usb_gadget_connect(struct usb_gadget *gadget); 565 int usb_gadget_disconnect(struct usb_gadget *gadget); 566 int usb_gadget_deactivate(struct usb_gadget *gadget); 567 int usb_gadget_activate(struct usb_gadget *gadget); 568 #else 569 static inline int usb_gadget_frame_number(struct usb_gadget *gadget) 570 { return 0; } 571 static inline int usb_gadget_wakeup(struct usb_gadget *gadget) 572 { return 0; } 573 static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) 574 { return 0; } 575 static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) 576 { return 0; } 577 static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) 578 { return 0; } 579 static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) 580 { return 0; } 581 static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) 582 { return 0; } 583 static inline int usb_gadget_connect(struct usb_gadget *gadget) 584 { return 0; } 585 static inline int usb_gadget_disconnect(struct usb_gadget *gadget) 586 { return 0; } 587 static inline int usb_gadget_deactivate(struct usb_gadget *gadget) 588 { return 0; } 589 static inline int usb_gadget_activate(struct usb_gadget *gadget) 590 { return 0; } 591 #endif /* CONFIG_USB_GADGET */ 592 593 /*-------------------------------------------------------------------------*/ 594 595 /** 596 * struct usb_gadget_driver - driver for usb 'slave' devices 597 * @function: String describing the gadget's function 598 * @max_speed: Highest speed the driver handles. 599 * @setup: Invoked for ep0 control requests that aren't handled by 600 * the hardware level driver. Most calls must be handled by 601 * the gadget driver, including descriptor and configuration 602 * management. The 16 bit members of the setup data are in 603 * USB byte order. Called in_interrupt; this may not sleep. Driver 604 * queues a response to ep0, or returns negative to stall. 605 * @disconnect: Invoked after all transfers have been stopped, 606 * when the host is disconnected. May be called in_interrupt; this 607 * may not sleep. Some devices can't detect disconnect, so this might 608 * not be called except as part of controller shutdown. 609 * @bind: the driver's bind callback 610 * @unbind: Invoked when the driver is unbound from a gadget, 611 * usually from rmmod (after a disconnect is reported). 612 * Called in a context that permits sleeping. 613 * @suspend: Invoked on USB suspend. May be called in_interrupt. 614 * @resume: Invoked on USB resume. May be called in_interrupt. 615 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers 616 * and should be called in_interrupt. 617 * @driver: Driver model state for this driver. 618 * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, 619 * this driver will be bound to any available UDC. 620 * @pending: UDC core private data used for deferred probe of this driver. 621 * @match_existing_only: If udc is not found, return an error and don't add this 622 * gadget driver to list of pending driver 623 * 624 * Devices are disabled till a gadget driver successfully bind()s, which 625 * means the driver will handle setup() requests needed to enumerate (and 626 * meet "chapter 9" requirements) then do some useful work. 627 * 628 * If gadget->is_otg is true, the gadget driver must provide an OTG 629 * descriptor during enumeration, or else fail the bind() call. In such 630 * cases, no USB traffic may flow until both bind() returns without 631 * having called usb_gadget_disconnect(), and the USB host stack has 632 * initialized. 633 * 634 * Drivers use hardware-specific knowledge to configure the usb hardware. 635 * endpoint addressing is only one of several hardware characteristics that 636 * are in descriptors the ep0 implementation returns from setup() calls. 637 * 638 * Except for ep0 implementation, most driver code shouldn't need change to 639 * run on top of different usb controllers. It'll use endpoints set up by 640 * that ep0 implementation. 641 * 642 * The usb controller driver handles a few standard usb requests. Those 643 * include set_address, and feature flags for devices, interfaces, and 644 * endpoints (the get_status, set_feature, and clear_feature requests). 645 * 646 * Accordingly, the driver's setup() callback must always implement all 647 * get_descriptor requests, returning at least a device descriptor and 648 * a configuration descriptor. Drivers must make sure the endpoint 649 * descriptors match any hardware constraints. Some hardware also constrains 650 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). 651 * 652 * The driver's setup() callback must also implement set_configuration, 653 * and should also implement set_interface, get_configuration, and 654 * get_interface. Setting a configuration (or interface) is where 655 * endpoints should be activated or (config 0) shut down. 656 * 657 * (Note that only the default control endpoint is supported. Neither 658 * hosts nor devices generally support control traffic except to ep0.) 659 * 660 * Most devices will ignore USB suspend/resume operations, and so will 661 * not provide those callbacks. However, some may need to change modes 662 * when the host is not longer directing those activities. For example, 663 * local controls (buttons, dials, etc) may need to be re-enabled since 664 * the (remote) host can't do that any longer; or an error state might 665 * be cleared, to make the device behave identically whether or not 666 * power is maintained. 667 */ 668 struct usb_gadget_driver { 669 char *function; 670 enum usb_device_speed max_speed; 671 int (*bind)(struct usb_gadget *gadget, 672 struct usb_gadget_driver *driver); 673 void (*unbind)(struct usb_gadget *); 674 int (*setup)(struct usb_gadget *, 675 const struct usb_ctrlrequest *); 676 void (*disconnect)(struct usb_gadget *); 677 void (*suspend)(struct usb_gadget *); 678 void (*resume)(struct usb_gadget *); 679 void (*reset)(struct usb_gadget *); 680 681 /* FIXME support safe rmmod */ 682 struct device_driver driver; 683 684 char *udc_name; 685 struct list_head pending; 686 unsigned match_existing_only:1; 687 }; 688 689 690 691 /*-------------------------------------------------------------------------*/ 692 693 /* driver modules register and unregister, as usual. 694 * these calls must be made in a context that can sleep. 695 * 696 * these will usually be implemented directly by the hardware-dependent 697 * usb bus interface driver, which will only support a single driver. 698 */ 699 700 /** 701 * usb_gadget_probe_driver - probe a gadget driver 702 * @driver: the driver being registered 703 * Context: can sleep 704 * 705 * Call this in your gadget driver's module initialization function, 706 * to tell the underlying usb controller driver about your driver. 707 * The @bind() function will be called to bind it to a gadget before this 708 * registration call returns. It's expected that the @bind() function will 709 * be in init sections. 710 */ 711 int usb_gadget_probe_driver(struct usb_gadget_driver *driver); 712 713 /** 714 * usb_gadget_unregister_driver - unregister a gadget driver 715 * @driver:the driver being unregistered 716 * Context: can sleep 717 * 718 * Call this in your gadget driver's module cleanup function, 719 * to tell the underlying usb controller that your driver is 720 * going away. If the controller is connected to a USB host, 721 * it will first disconnect(). The driver is also requested 722 * to unbind() and clean up any device state, before this procedure 723 * finally returns. It's expected that the unbind() functions 724 * will in in exit sections, so may not be linked in some kernels. 725 */ 726 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); 727 728 extern int usb_add_gadget_udc_release(struct device *parent, 729 struct usb_gadget *gadget, void (*release)(struct device *dev)); 730 extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); 731 extern void usb_del_gadget_udc(struct usb_gadget *gadget); 732 extern char *usb_get_gadget_udc_name(void); 733 734 /*-------------------------------------------------------------------------*/ 735 736 /* utility to simplify dealing with string descriptors */ 737 738 /** 739 * struct usb_string - wraps a C string and its USB id 740 * @id:the (nonzero) ID for this string 741 * @s:the string, in UTF-8 encoding 742 * 743 * If you're using usb_gadget_get_string(), use this to wrap a string 744 * together with its ID. 745 */ 746 struct usb_string { 747 u8 id; 748 const char *s; 749 }; 750 751 /** 752 * struct usb_gadget_strings - a set of USB strings in a given language 753 * @language:identifies the strings' language (0x0409 for en-us) 754 * @strings:array of strings with their ids 755 * 756 * If you're using usb_gadget_get_string(), use this to wrap all the 757 * strings for a given language. 758 */ 759 struct usb_gadget_strings { 760 u16 language; /* 0x0409 for en-us */ 761 struct usb_string *strings; 762 }; 763 764 struct usb_gadget_string_container { 765 struct list_head list; 766 u8 *stash[0]; 767 }; 768 769 /* put descriptor for string with that id into buf (buflen >= 256) */ 770 int usb_gadget_get_string(const struct usb_gadget_strings *table, int id, u8 *buf); 771 772 /*-------------------------------------------------------------------------*/ 773 774 /* utility to simplify managing config descriptors */ 775 776 /* write vector of descriptors into buffer */ 777 int usb_descriptor_fillbuf(void *, unsigned, 778 const struct usb_descriptor_header **); 779 780 /* build config descriptor from single descriptor vector */ 781 int usb_gadget_config_buf(const struct usb_config_descriptor *config, 782 void *buf, unsigned buflen, const struct usb_descriptor_header **desc); 783 784 /* copy a NULL-terminated vector of descriptors */ 785 struct usb_descriptor_header **usb_copy_descriptors( 786 struct usb_descriptor_header **); 787 788 /** 789 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors() 790 * @v: vector of descriptors 791 */ 792 static inline void usb_free_descriptors(struct usb_descriptor_header **v) 793 { 794 kfree(v); 795 } 796 797 struct usb_function; 798 int usb_assign_descriptors(struct usb_function *f, 799 struct usb_descriptor_header **fs, 800 struct usb_descriptor_header **hs, 801 struct usb_descriptor_header **ss, 802 struct usb_descriptor_header **ssp); 803 void usb_free_all_descriptors(struct usb_function *f); 804 805 struct usb_descriptor_header *usb_otg_descriptor_alloc( 806 struct usb_gadget *gadget); 807 int usb_otg_descriptor_init(struct usb_gadget *gadget, 808 struct usb_descriptor_header *otg_desc); 809 /*-------------------------------------------------------------------------*/ 810 811 /* utility to simplify map/unmap of usb_requests to/from DMA */ 812 813 #ifdef CONFIG_HAS_DMA 814 extern int usb_gadget_map_request_by_dev(struct device *dev, 815 struct usb_request *req, int is_in); 816 extern int usb_gadget_map_request(struct usb_gadget *gadget, 817 struct usb_request *req, int is_in); 818 819 extern void usb_gadget_unmap_request_by_dev(struct device *dev, 820 struct usb_request *req, int is_in); 821 extern void usb_gadget_unmap_request(struct usb_gadget *gadget, 822 struct usb_request *req, int is_in); 823 #else /* !CONFIG_HAS_DMA */ 824 static inline int usb_gadget_map_request_by_dev(struct device *dev, 825 struct usb_request *req, int is_in) { return -ENOSYS; } 826 static inline int usb_gadget_map_request(struct usb_gadget *gadget, 827 struct usb_request *req, int is_in) { return -ENOSYS; } 828 829 static inline void usb_gadget_unmap_request_by_dev(struct device *dev, 830 struct usb_request *req, int is_in) { } 831 static inline void usb_gadget_unmap_request(struct usb_gadget *gadget, 832 struct usb_request *req, int is_in) { } 833 #endif /* !CONFIG_HAS_DMA */ 834 835 /*-------------------------------------------------------------------------*/ 836 837 /* utility to set gadget state properly */ 838 839 extern void usb_gadget_set_state(struct usb_gadget *gadget, 840 enum usb_device_state state); 841 842 /*-------------------------------------------------------------------------*/ 843 844 /* utility to tell udc core that the bus reset occurs */ 845 extern void usb_gadget_udc_reset(struct usb_gadget *gadget, 846 struct usb_gadget_driver *driver); 847 848 /*-------------------------------------------------------------------------*/ 849 850 /* utility to give requests back to the gadget layer */ 851 852 extern void usb_gadget_giveback_request(struct usb_ep *ep, 853 struct usb_request *req); 854 855 /*-------------------------------------------------------------------------*/ 856 857 /* utility to find endpoint by name */ 858 859 extern struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, 860 const char *name); 861 862 /*-------------------------------------------------------------------------*/ 863 864 /* utility to check if endpoint caps match descriptor needs */ 865 866 extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget, 867 struct usb_ep *ep, struct usb_endpoint_descriptor *desc, 868 struct usb_ss_ep_comp_descriptor *ep_comp); 869 870 /*-------------------------------------------------------------------------*/ 871 872 /* utility to update vbus status for udc core, it may be scheduled */ 873 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status); 874 875 /*-------------------------------------------------------------------------*/ 876 877 /* utility wrapping a simple endpoint selection policy */ 878 879 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, 880 struct usb_endpoint_descriptor *); 881 882 883 extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *, 884 struct usb_endpoint_descriptor *, 885 struct usb_ss_ep_comp_descriptor *); 886 887 extern void usb_ep_autoconfig_release(struct usb_ep *); 888 889 extern void usb_ep_autoconfig_reset(struct usb_gadget *); 890 891 #endif /* __LINUX_USB_GADGET_H */ 892