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