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