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_gadget *, 314 struct usb_dcd_config_params *); 315 int (*udc_start)(struct usb_gadget *, 316 struct usb_gadget_driver *); 317 int (*udc_stop)(struct usb_gadget *); 318 void (*udc_set_speed)(struct usb_gadget *, enum usb_device_speed); 319 struct usb_ep *(*match_ep)(struct usb_gadget *, 320 struct usb_endpoint_descriptor *, 321 struct usb_ss_ep_comp_descriptor *); 322 }; 323 324 /** 325 * struct usb_gadget - represents a usb slave device 326 * @work: (internal use) Workqueue to be used for sysfs_notify() 327 * @udc: struct usb_udc pointer for this gadget 328 * @ops: Function pointers used to access hardware-specific operations. 329 * @ep0: Endpoint zero, used when reading or writing responses to 330 * driver setup() requests 331 * @ep_list: List of other endpoints supported by the device. 332 * @speed: Speed of current connection to USB host. 333 * @max_speed: Maximal speed the UDC can handle. UDC must support this 334 * and all slower speeds. 335 * @state: the state we are now (attached, suspended, configured, etc) 336 * @name: Identifies the controller hardware type. Used in diagnostics 337 * and sometimes configuration. 338 * @dev: Driver model state for this abstract device. 339 * @isoch_delay: value from Set Isoch Delay request. Only valid on SS/SSP 340 * @out_epnum: last used out ep number 341 * @in_epnum: last used in ep number 342 * @mA: last set mA value 343 * @otg_caps: OTG capabilities of this gadget. 344 * @sg_supported: true if we can handle scatter-gather 345 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the 346 * gadget driver must provide a USB OTG descriptor. 347 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable 348 * is in the Mini-AB jack, and HNP has been used to switch roles 349 * so that the "A" device currently acts as A-Peripheral, not A-Host. 350 * @a_hnp_support: OTG device feature flag, indicating that the A-Host 351 * supports HNP at this port. 352 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host 353 * only supports HNP on a different root port. 354 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host 355 * enabled HNP support. 356 * @hnp_polling_support: OTG device feature flag, indicating if the OTG device 357 * in peripheral mode can support HNP polling. 358 * @host_request_flag: OTG device feature flag, indicating if A-Peripheral 359 * or B-Peripheral wants to take host role. 360 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to 361 * MaxPacketSize. 362 * @quirk_altset_not_supp: UDC controller doesn't support alt settings. 363 * @quirk_stall_not_supp: UDC controller doesn't support stalling. 364 * @quirk_zlp_not_supp: UDC controller doesn't support ZLP. 365 * @quirk_avoids_skb_reserve: udc/platform wants to avoid skb_reserve() in 366 * u_ether.c to improve performance. 367 * @is_selfpowered: if the gadget is self-powered. 368 * @deactivated: True if gadget is deactivated - in deactivated state it cannot 369 * be connected. 370 * @connected: True if gadget is connected. 371 * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag 372 * indicates that it supports LPM as per the LPM ECN & errata. 373 * 374 * Gadgets have a mostly-portable "gadget driver" implementing device 375 * functions, handling all usb configurations and interfaces. Gadget 376 * drivers talk to hardware-specific code indirectly, through ops vectors. 377 * That insulates the gadget driver from hardware details, and packages 378 * the hardware endpoints through generic i/o queues. The "usb_gadget" 379 * and "usb_ep" interfaces provide that insulation from the hardware. 380 * 381 * Except for the driver data, all fields in this structure are 382 * read-only to the gadget driver. That driver data is part of the 383 * "driver model" infrastructure in 2.6 (and later) kernels, and for 384 * earlier systems is grouped in a similar structure that's not known 385 * to the rest of the kernel. 386 * 387 * Values of the three OTG device feature flags are updated before the 388 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before 389 * driver suspend() calls. They are valid only when is_otg, and when the 390 * device is acting as a B-Peripheral (so is_a_peripheral is false). 391 */ 392 struct usb_gadget { 393 struct work_struct work; 394 struct usb_udc *udc; 395 /* readonly to gadget driver */ 396 const struct usb_gadget_ops *ops; 397 struct usb_ep *ep0; 398 struct list_head ep_list; /* of usb_ep */ 399 enum usb_device_speed speed; 400 enum usb_device_speed max_speed; 401 enum usb_device_state state; 402 const char *name; 403 struct device dev; 404 unsigned isoch_delay; 405 unsigned out_epnum; 406 unsigned in_epnum; 407 unsigned mA; 408 struct usb_otg_caps *otg_caps; 409 410 unsigned sg_supported:1; 411 unsigned is_otg:1; 412 unsigned is_a_peripheral:1; 413 unsigned b_hnp_enable:1; 414 unsigned a_hnp_support:1; 415 unsigned a_alt_hnp_support:1; 416 unsigned hnp_polling_support:1; 417 unsigned host_request_flag:1; 418 unsigned quirk_ep_out_aligned_size:1; 419 unsigned quirk_altset_not_supp:1; 420 unsigned quirk_stall_not_supp:1; 421 unsigned quirk_zlp_not_supp:1; 422 unsigned quirk_avoids_skb_reserve:1; 423 unsigned is_selfpowered:1; 424 unsigned deactivated:1; 425 unsigned connected:1; 426 unsigned lpm_capable:1; 427 }; 428 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work)) 429 430 static inline void set_gadget_data(struct usb_gadget *gadget, void *data) 431 { dev_set_drvdata(&gadget->dev, data); } 432 static inline void *get_gadget_data(struct usb_gadget *gadget) 433 { return dev_get_drvdata(&gadget->dev); } 434 static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) 435 { 436 return container_of(dev, struct usb_gadget, dev); 437 } 438 439 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ 440 #define gadget_for_each_ep(tmp, gadget) \ 441 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) 442 443 /** 444 * usb_ep_align - returns @len aligned to ep's maxpacketsize. 445 * @ep: the endpoint whose maxpacketsize is used to align @len 446 * @len: buffer size's length to align to @ep's maxpacketsize 447 * 448 * This helper is used to align buffer's size to an ep's maxpacketsize. 449 */ 450 static inline size_t usb_ep_align(struct usb_ep *ep, size_t len) 451 { 452 int max_packet_size = (size_t)usb_endpoint_maxp(ep->desc) & 0x7ff; 453 454 return round_up(len, max_packet_size); 455 } 456 457 /** 458 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget 459 * requires quirk_ep_out_aligned_size, otherwise returns len. 460 * @g: controller to check for quirk 461 * @ep: the endpoint whose maxpacketsize is used to align @len 462 * @len: buffer size's length to align to @ep's maxpacketsize 463 * 464 * This helper is used in case it's required for any reason to check and maybe 465 * align buffer's size to an ep's maxpacketsize. 466 */ 467 static inline size_t 468 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len) 469 { 470 return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len; 471 } 472 473 /** 474 * gadget_is_altset_supported - return true iff the hardware supports 475 * altsettings 476 * @g: controller to check for quirk 477 */ 478 static inline int gadget_is_altset_supported(struct usb_gadget *g) 479 { 480 return !g->quirk_altset_not_supp; 481 } 482 483 /** 484 * gadget_is_stall_supported - return true iff the hardware supports stalling 485 * @g: controller to check for quirk 486 */ 487 static inline int gadget_is_stall_supported(struct usb_gadget *g) 488 { 489 return !g->quirk_stall_not_supp; 490 } 491 492 /** 493 * gadget_is_zlp_supported - return true iff the hardware supports zlp 494 * @g: controller to check for quirk 495 */ 496 static inline int gadget_is_zlp_supported(struct usb_gadget *g) 497 { 498 return !g->quirk_zlp_not_supp; 499 } 500 501 /** 502 * gadget_avoids_skb_reserve - return true iff the hardware would like to avoid 503 * skb_reserve to improve performance. 504 * @g: controller to check for quirk 505 */ 506 static inline int gadget_avoids_skb_reserve(struct usb_gadget *g) 507 { 508 return g->quirk_avoids_skb_reserve; 509 } 510 511 /** 512 * gadget_is_dualspeed - return true iff the hardware handles high speed 513 * @g: controller that might support both high and full speeds 514 */ 515 static inline int gadget_is_dualspeed(struct usb_gadget *g) 516 { 517 return g->max_speed >= USB_SPEED_HIGH; 518 } 519 520 /** 521 * gadget_is_superspeed() - return true if the hardware handles superspeed 522 * @g: controller that might support superspeed 523 */ 524 static inline int gadget_is_superspeed(struct usb_gadget *g) 525 { 526 return g->max_speed >= USB_SPEED_SUPER; 527 } 528 529 /** 530 * gadget_is_superspeed_plus() - return true if the hardware handles 531 * superspeed plus 532 * @g: controller that might support superspeed plus 533 */ 534 static inline int gadget_is_superspeed_plus(struct usb_gadget *g) 535 { 536 return g->max_speed >= USB_SPEED_SUPER_PLUS; 537 } 538 539 /** 540 * gadget_is_otg - return true iff the hardware is OTG-ready 541 * @g: controller that might have a Mini-AB connector 542 * 543 * This is a runtime test, since kernels with a USB-OTG stack sometimes 544 * run on boards which only have a Mini-B (or Mini-A) connector. 545 */ 546 static inline int gadget_is_otg(struct usb_gadget *g) 547 { 548 #ifdef CONFIG_USB_OTG 549 return g->is_otg; 550 #else 551 return 0; 552 #endif 553 } 554 555 /*-------------------------------------------------------------------------*/ 556 557 #if IS_ENABLED(CONFIG_USB_GADGET) 558 int usb_gadget_frame_number(struct usb_gadget *gadget); 559 int usb_gadget_wakeup(struct usb_gadget *gadget); 560 int usb_gadget_set_selfpowered(struct usb_gadget *gadget); 561 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget); 562 int usb_gadget_vbus_connect(struct usb_gadget *gadget); 563 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA); 564 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget); 565 int usb_gadget_connect(struct usb_gadget *gadget); 566 int usb_gadget_disconnect(struct usb_gadget *gadget); 567 int usb_gadget_deactivate(struct usb_gadget *gadget); 568 int usb_gadget_activate(struct usb_gadget *gadget); 569 #else 570 static inline int usb_gadget_frame_number(struct usb_gadget *gadget) 571 { return 0; } 572 static inline int usb_gadget_wakeup(struct usb_gadget *gadget) 573 { return 0; } 574 static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) 575 { return 0; } 576 static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) 577 { return 0; } 578 static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) 579 { return 0; } 580 static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) 581 { return 0; } 582 static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) 583 { return 0; } 584 static inline int usb_gadget_connect(struct usb_gadget *gadget) 585 { return 0; } 586 static inline int usb_gadget_disconnect(struct usb_gadget *gadget) 587 { return 0; } 588 static inline int usb_gadget_deactivate(struct usb_gadget *gadget) 589 { return 0; } 590 static inline int usb_gadget_activate(struct usb_gadget *gadget) 591 { return 0; } 592 #endif /* CONFIG_USB_GADGET */ 593 594 /*-------------------------------------------------------------------------*/ 595 596 /** 597 * struct usb_gadget_driver - driver for usb 'slave' devices 598 * @function: String describing the gadget's function 599 * @max_speed: Highest speed the driver handles. 600 * @setup: Invoked for ep0 control requests that aren't handled by 601 * the hardware level driver. Most calls must be handled by 602 * the gadget driver, including descriptor and configuration 603 * management. The 16 bit members of the setup data are in 604 * USB byte order. Called in_interrupt; this may not sleep. Driver 605 * queues a response to ep0, or returns negative to stall. 606 * @disconnect: Invoked after all transfers have been stopped, 607 * when the host is disconnected. May be called in_interrupt; this 608 * may not sleep. Some devices can't detect disconnect, so this might 609 * not be called except as part of controller shutdown. 610 * @bind: the driver's bind callback 611 * @unbind: Invoked when the driver is unbound from a gadget, 612 * usually from rmmod (after a disconnect is reported). 613 * Called in a context that permits sleeping. 614 * @suspend: Invoked on USB suspend. May be called in_interrupt. 615 * @resume: Invoked on USB resume. May be called in_interrupt. 616 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers 617 * and should be called in_interrupt. 618 * @driver: Driver model state for this driver. 619 * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, 620 * this driver will be bound to any available UDC. 621 * @pending: UDC core private data used for deferred probe of this driver. 622 * @match_existing_only: If udc is not found, return an error and don't add this 623 * gadget driver to list of pending driver 624 * 625 * Devices are disabled till a gadget driver successfully bind()s, which 626 * means the driver will handle setup() requests needed to enumerate (and 627 * meet "chapter 9" requirements) then do some useful work. 628 * 629 * If gadget->is_otg is true, the gadget driver must provide an OTG 630 * descriptor during enumeration, or else fail the bind() call. In such 631 * cases, no USB traffic may flow until both bind() returns without 632 * having called usb_gadget_disconnect(), and the USB host stack has 633 * initialized. 634 * 635 * Drivers use hardware-specific knowledge to configure the usb hardware. 636 * endpoint addressing is only one of several hardware characteristics that 637 * are in descriptors the ep0 implementation returns from setup() calls. 638 * 639 * Except for ep0 implementation, most driver code shouldn't need change to 640 * run on top of different usb controllers. It'll use endpoints set up by 641 * that ep0 implementation. 642 * 643 * The usb controller driver handles a few standard usb requests. Those 644 * include set_address, and feature flags for devices, interfaces, and 645 * endpoints (the get_status, set_feature, and clear_feature requests). 646 * 647 * Accordingly, the driver's setup() callback must always implement all 648 * get_descriptor requests, returning at least a device descriptor and 649 * a configuration descriptor. Drivers must make sure the endpoint 650 * descriptors match any hardware constraints. Some hardware also constrains 651 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). 652 * 653 * The driver's setup() callback must also implement set_configuration, 654 * and should also implement set_interface, get_configuration, and 655 * get_interface. Setting a configuration (or interface) is where 656 * endpoints should be activated or (config 0) shut down. 657 * 658 * (Note that only the default control endpoint is supported. Neither 659 * hosts nor devices generally support control traffic except to ep0.) 660 * 661 * Most devices will ignore USB suspend/resume operations, and so will 662 * not provide those callbacks. However, some may need to change modes 663 * when the host is not longer directing those activities. For example, 664 * local controls (buttons, dials, etc) may need to be re-enabled since 665 * the (remote) host can't do that any longer; or an error state might 666 * be cleared, to make the device behave identically whether or not 667 * power is maintained. 668 */ 669 struct usb_gadget_driver { 670 char *function; 671 enum usb_device_speed max_speed; 672 int (*bind)(struct usb_gadget *gadget, 673 struct usb_gadget_driver *driver); 674 void (*unbind)(struct usb_gadget *); 675 int (*setup)(struct usb_gadget *, 676 const struct usb_ctrlrequest *); 677 void (*disconnect)(struct usb_gadget *); 678 void (*suspend)(struct usb_gadget *); 679 void (*resume)(struct usb_gadget *); 680 void (*reset)(struct usb_gadget *); 681 682 /* FIXME support safe rmmod */ 683 struct device_driver driver; 684 685 char *udc_name; 686 struct list_head pending; 687 unsigned match_existing_only:1; 688 }; 689 690 691 692 /*-------------------------------------------------------------------------*/ 693 694 /* driver modules register and unregister, as usual. 695 * these calls must be made in a context that can sleep. 696 * 697 * these will usually be implemented directly by the hardware-dependent 698 * usb bus interface driver, which will only support a single driver. 699 */ 700 701 /** 702 * usb_gadget_probe_driver - probe a gadget driver 703 * @driver: the driver being registered 704 * Context: can sleep 705 * 706 * Call this in your gadget driver's module initialization function, 707 * to tell the underlying usb controller driver about your driver. 708 * The @bind() function will be called to bind it to a gadget before this 709 * registration call returns. It's expected that the @bind() function will 710 * be in init sections. 711 */ 712 int usb_gadget_probe_driver(struct usb_gadget_driver *driver); 713 714 /** 715 * usb_gadget_unregister_driver - unregister a gadget driver 716 * @driver:the driver being unregistered 717 * Context: can sleep 718 * 719 * Call this in your gadget driver's module cleanup function, 720 * to tell the underlying usb controller that your driver is 721 * going away. If the controller is connected to a USB host, 722 * it will first disconnect(). The driver is also requested 723 * to unbind() and clean up any device state, before this procedure 724 * finally returns. It's expected that the unbind() functions 725 * will in in exit sections, so may not be linked in some kernels. 726 */ 727 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); 728 729 extern int usb_add_gadget_udc_release(struct device *parent, 730 struct usb_gadget *gadget, void (*release)(struct device *dev)); 731 extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); 732 extern void usb_del_gadget_udc(struct usb_gadget *gadget); 733 extern char *usb_get_gadget_udc_name(void); 734 735 /*-------------------------------------------------------------------------*/ 736 737 /* utility to simplify dealing with string descriptors */ 738 739 /** 740 * struct usb_string - wraps a C string and its USB id 741 * @id:the (nonzero) ID for this string 742 * @s:the string, in UTF-8 encoding 743 * 744 * If you're using usb_gadget_get_string(), use this to wrap a string 745 * together with its ID. 746 */ 747 struct usb_string { 748 u8 id; 749 const char *s; 750 }; 751 752 /** 753 * struct usb_gadget_strings - a set of USB strings in a given language 754 * @language:identifies the strings' language (0x0409 for en-us) 755 * @strings:array of strings with their ids 756 * 757 * If you're using usb_gadget_get_string(), use this to wrap all the 758 * strings for a given language. 759 */ 760 struct usb_gadget_strings { 761 u16 language; /* 0x0409 for en-us */ 762 struct usb_string *strings; 763 }; 764 765 struct usb_gadget_string_container { 766 struct list_head list; 767 u8 *stash[0]; 768 }; 769 770 /* put descriptor for string with that id into buf (buflen >= 256) */ 771 int usb_gadget_get_string(const struct usb_gadget_strings *table, int id, u8 *buf); 772 773 /*-------------------------------------------------------------------------*/ 774 775 /* utility to simplify managing config descriptors */ 776 777 /* write vector of descriptors into buffer */ 778 int usb_descriptor_fillbuf(void *, unsigned, 779 const struct usb_descriptor_header **); 780 781 /* build config descriptor from single descriptor vector */ 782 int usb_gadget_config_buf(const struct usb_config_descriptor *config, 783 void *buf, unsigned buflen, const struct usb_descriptor_header **desc); 784 785 /* copy a NULL-terminated vector of descriptors */ 786 struct usb_descriptor_header **usb_copy_descriptors( 787 struct usb_descriptor_header **); 788 789 /** 790 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors() 791 * @v: vector of descriptors 792 */ 793 static inline void usb_free_descriptors(struct usb_descriptor_header **v) 794 { 795 kfree(v); 796 } 797 798 struct usb_function; 799 int usb_assign_descriptors(struct usb_function *f, 800 struct usb_descriptor_header **fs, 801 struct usb_descriptor_header **hs, 802 struct usb_descriptor_header **ss, 803 struct usb_descriptor_header **ssp); 804 void usb_free_all_descriptors(struct usb_function *f); 805 806 struct usb_descriptor_header *usb_otg_descriptor_alloc( 807 struct usb_gadget *gadget); 808 int usb_otg_descriptor_init(struct usb_gadget *gadget, 809 struct usb_descriptor_header *otg_desc); 810 /*-------------------------------------------------------------------------*/ 811 812 /* utility to simplify map/unmap of usb_requests to/from DMA */ 813 814 #ifdef CONFIG_HAS_DMA 815 extern int usb_gadget_map_request_by_dev(struct device *dev, 816 struct usb_request *req, int is_in); 817 extern int usb_gadget_map_request(struct usb_gadget *gadget, 818 struct usb_request *req, int is_in); 819 820 extern void usb_gadget_unmap_request_by_dev(struct device *dev, 821 struct usb_request *req, int is_in); 822 extern void usb_gadget_unmap_request(struct usb_gadget *gadget, 823 struct usb_request *req, int is_in); 824 #else /* !CONFIG_HAS_DMA */ 825 static inline int usb_gadget_map_request_by_dev(struct device *dev, 826 struct usb_request *req, int is_in) { return -ENOSYS; } 827 static inline int usb_gadget_map_request(struct usb_gadget *gadget, 828 struct usb_request *req, int is_in) { return -ENOSYS; } 829 830 static inline void usb_gadget_unmap_request_by_dev(struct device *dev, 831 struct usb_request *req, int is_in) { } 832 static inline void usb_gadget_unmap_request(struct usb_gadget *gadget, 833 struct usb_request *req, int is_in) { } 834 #endif /* !CONFIG_HAS_DMA */ 835 836 /*-------------------------------------------------------------------------*/ 837 838 /* utility to set gadget state properly */ 839 840 extern void usb_gadget_set_state(struct usb_gadget *gadget, 841 enum usb_device_state state); 842 843 /*-------------------------------------------------------------------------*/ 844 845 /* utility to tell udc core that the bus reset occurs */ 846 extern void usb_gadget_udc_reset(struct usb_gadget *gadget, 847 struct usb_gadget_driver *driver); 848 849 /*-------------------------------------------------------------------------*/ 850 851 /* utility to give requests back to the gadget layer */ 852 853 extern void usb_gadget_giveback_request(struct usb_ep *ep, 854 struct usb_request *req); 855 856 /*-------------------------------------------------------------------------*/ 857 858 /* utility to find endpoint by name */ 859 860 extern struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, 861 const char *name); 862 863 /*-------------------------------------------------------------------------*/ 864 865 /* utility to check if endpoint caps match descriptor needs */ 866 867 extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget, 868 struct usb_ep *ep, struct usb_endpoint_descriptor *desc, 869 struct usb_ss_ep_comp_descriptor *ep_comp); 870 871 /*-------------------------------------------------------------------------*/ 872 873 /* utility to update vbus status for udc core, it may be scheduled */ 874 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status); 875 876 /*-------------------------------------------------------------------------*/ 877 878 /* utility wrapping a simple endpoint selection policy */ 879 880 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, 881 struct usb_endpoint_descriptor *); 882 883 884 extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *, 885 struct usb_endpoint_descriptor *, 886 struct usb_ss_ep_comp_descriptor *); 887 888 extern void usb_ep_autoconfig_release(struct usb_ep *); 889 890 extern void usb_ep_autoconfig_reset(struct usb_gadget *); 891 892 #endif /* __LINUX_USB_GADGET_H */ 893