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 * talk to many USB gadgets, but the gadgets are only able to communicate 8 * to one host. 9 * 10 * 11 * (C) Copyright 2002-2004 by David Brownell 12 * All Rights Reserved. 13 */ 14 15 #ifndef __LINUX_USB_GADGET_H 16 #define __LINUX_USB_GADGET_H 17 18 #include <linux/configfs.h> 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 * @is_last: Indicates if this is the last request of a stream_id before 46 * switching to a different stream (required for DWC3 controllers). 47 * @no_interrupt: If true, hints that no completion irq is needed. 48 * Helpful sometimes with deep request queues that are handled 49 * directly by DMA controllers. 50 * @zero: If true, when writing data, makes the last packet be "short" 51 * by adding a zero length packet as needed; 52 * @short_not_ok: When reading data, makes short packets be 53 * treated as errors (queue stops advancing till cleanup). 54 * @dma_mapped: Indicates if request has been mapped to DMA (internal) 55 * @complete: Function called when request completes, so this request and 56 * its buffer may be re-used. The function will always be called with 57 * interrupts disabled, and it must not sleep. 58 * Reads terminate with a short packet, or when the buffer fills, 59 * whichever comes first. When writes terminate, some data bytes 60 * will usually still be in flight (often in a hardware fifo). 61 * Errors (for reads or writes) stop the queue from advancing 62 * until the completion function returns, so that any transfers 63 * invalidated by the error may first be dequeued. 64 * @context: For use by the completion callback 65 * @list: For use by the gadget driver. 66 * @frame_number: Reports the interval number in (micro)frame in which the 67 * isochronous transfer was transmitted or received. 68 * @status: Reports completion code, zero or a negative errno. 69 * Normally, faults block the transfer queue from advancing until 70 * the completion callback returns. 71 * Code "-ESHUTDOWN" indicates completion caused by device disconnect, 72 * or when the driver disabled the endpoint. 73 * @actual: Reports bytes transferred to/from the buffer. For reads (OUT 74 * transfers) this may be less than the requested length. If the 75 * short_not_ok flag is set, short reads are treated as errors 76 * even when status otherwise indicates successful completion. 77 * Note that for writes (IN transfers) some data bytes may still 78 * reside in a device-side FIFO when the request is reported as 79 * complete. 80 * 81 * These are allocated/freed through the endpoint they're used with. The 82 * hardware's driver can add extra per-request data to the memory it returns, 83 * which often avoids separate memory allocations (potential failures), 84 * later when the request is queued. 85 * 86 * Request flags affect request handling, such as whether a zero length 87 * packet is written (the "zero" flag), whether a short read should be 88 * treated as an error (blocking request queue advance, the "short_not_ok" 89 * flag), or hinting that an interrupt is not required (the "no_interrupt" 90 * flag, for use with deep request queues). 91 * 92 * Bulk endpoints can use any size buffers, and can also be used for interrupt 93 * transfers. interrupt-only endpoints can be much less functional. 94 * 95 * NOTE: this is analogous to 'struct urb' on the host side, except that 96 * it's thinner and promotes more pre-allocation. 97 */ 98 99 struct usb_request { 100 void *buf; 101 unsigned length; 102 dma_addr_t dma; 103 104 struct scatterlist *sg; 105 unsigned num_sgs; 106 unsigned num_mapped_sgs; 107 108 unsigned stream_id:16; 109 unsigned is_last:1; 110 unsigned no_interrupt:1; 111 unsigned zero:1; 112 unsigned short_not_ok:1; 113 unsigned dma_mapped:1; 114 115 void (*complete)(struct usb_ep *ep, 116 struct usb_request *req); 117 void *context; 118 struct list_head list; 119 120 unsigned frame_number; /* ISO ONLY */ 121 122 int status; 123 unsigned actual; 124 }; 125 126 /*-------------------------------------------------------------------------*/ 127 128 /* endpoint-specific parts of the api to the usb controller hardware. 129 * unlike the urb model, (de)multiplexing layers are not required. 130 * (so this api could slash overhead if used on the host side...) 131 * 132 * note that device side usb controllers commonly differ in how many 133 * endpoints they support, as well as their capabilities. 134 */ 135 struct usb_ep_ops { 136 int (*enable) (struct usb_ep *ep, 137 const struct usb_endpoint_descriptor *desc); 138 int (*disable) (struct usb_ep *ep); 139 void (*dispose) (struct usb_ep *ep); 140 141 struct usb_request *(*alloc_request) (struct usb_ep *ep, 142 gfp_t gfp_flags); 143 void (*free_request) (struct usb_ep *ep, struct usb_request *req); 144 145 int (*queue) (struct usb_ep *ep, struct usb_request *req, 146 gfp_t gfp_flags); 147 int (*dequeue) (struct usb_ep *ep, struct usb_request *req); 148 149 int (*set_halt) (struct usb_ep *ep, int value); 150 int (*set_wedge) (struct usb_ep *ep); 151 152 int (*fifo_status) (struct usb_ep *ep); 153 void (*fifo_flush) (struct usb_ep *ep); 154 }; 155 156 /** 157 * struct usb_ep_caps - endpoint capabilities description 158 * @type_control:Endpoint supports control type (reserved for ep0). 159 * @type_iso:Endpoint supports isochronous transfers. 160 * @type_bulk:Endpoint supports bulk transfers. 161 * @type_int:Endpoint supports interrupt transfers. 162 * @dir_in:Endpoint supports IN direction. 163 * @dir_out:Endpoint supports OUT direction. 164 */ 165 struct usb_ep_caps { 166 unsigned type_control:1; 167 unsigned type_iso:1; 168 unsigned type_bulk:1; 169 unsigned type_int:1; 170 unsigned dir_in:1; 171 unsigned dir_out:1; 172 }; 173 174 #define USB_EP_CAPS_TYPE_CONTROL 0x01 175 #define USB_EP_CAPS_TYPE_ISO 0x02 176 #define USB_EP_CAPS_TYPE_BULK 0x04 177 #define USB_EP_CAPS_TYPE_INT 0x08 178 #define USB_EP_CAPS_TYPE_ALL \ 179 (USB_EP_CAPS_TYPE_ISO | USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT) 180 #define USB_EP_CAPS_DIR_IN 0x01 181 #define USB_EP_CAPS_DIR_OUT 0x02 182 #define USB_EP_CAPS_DIR_ALL (USB_EP_CAPS_DIR_IN | USB_EP_CAPS_DIR_OUT) 183 184 #define USB_EP_CAPS(_type, _dir) \ 185 { \ 186 .type_control = !!(_type & USB_EP_CAPS_TYPE_CONTROL), \ 187 .type_iso = !!(_type & USB_EP_CAPS_TYPE_ISO), \ 188 .type_bulk = !!(_type & USB_EP_CAPS_TYPE_BULK), \ 189 .type_int = !!(_type & USB_EP_CAPS_TYPE_INT), \ 190 .dir_in = !!(_dir & USB_EP_CAPS_DIR_IN), \ 191 .dir_out = !!(_dir & USB_EP_CAPS_DIR_OUT), \ 192 } 193 194 /** 195 * struct usb_ep - device side representation of USB endpoint 196 * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk" 197 * @ops: Function pointers used to access hardware-specific operations. 198 * @ep_list:the gadget's ep_list holds all of its endpoints 199 * @caps:The structure describing types and directions supported by endpoint. 200 * @enabled: The current endpoint enabled/disabled state. 201 * @claimed: True if this endpoint is claimed by a function. 202 * @maxpacket:The maximum packet size used on this endpoint. The initial 203 * value can sometimes be reduced (hardware allowing), according to 204 * the endpoint descriptor used to configure the endpoint. 205 * @maxpacket_limit:The maximum packet size value which can be handled by this 206 * endpoint. It's set once by UDC driver when endpoint is initialized, and 207 * should not be changed. Should not be confused with maxpacket. 208 * @max_streams: The maximum number of streams supported 209 * by this EP (0 - 16, actual number is 2^n) 210 * @mult: multiplier, 'mult' value for SS Isoc EPs 211 * @maxburst: the maximum number of bursts supported by this EP (for usb3) 212 * @driver_data:for use by the gadget driver. 213 * @address: used to identify the endpoint when finding descriptor that 214 * matches connection speed 215 * @desc: endpoint descriptor. This pointer is set before the endpoint is 216 * enabled and remains valid until the endpoint is disabled. 217 * @comp_desc: In case of SuperSpeed support, this is the endpoint companion 218 * descriptor that is used to configure the endpoint 219 * 220 * the bus controller driver lists all the general purpose endpoints in 221 * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, 222 * and is accessed only in response to a driver setup() callback. 223 */ 224 225 struct usb_ep { 226 void *driver_data; 227 228 const char *name; 229 const struct usb_ep_ops *ops; 230 struct list_head ep_list; 231 struct usb_ep_caps caps; 232 bool claimed; 233 bool enabled; 234 unsigned maxpacket:16; 235 unsigned maxpacket_limit:16; 236 unsigned max_streams:16; 237 unsigned mult:2; 238 unsigned maxburst:5; 239 unsigned fifo_mode:1; 240 u8 address; 241 const struct usb_endpoint_descriptor *desc; 242 const struct usb_ss_ep_comp_descriptor *comp_desc; 243 }; 244 245 /*-------------------------------------------------------------------------*/ 246 247 #if IS_ENABLED(CONFIG_USB_GADGET) 248 void usb_ep_set_maxpacket_limit(struct usb_ep *ep, unsigned maxpacket_limit); 249 int usb_ep_enable(struct usb_ep *ep); 250 int usb_ep_disable(struct usb_ep *ep); 251 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags); 252 void usb_ep_free_request(struct usb_ep *ep, struct usb_request *req); 253 int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags); 254 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req); 255 int usb_ep_set_halt(struct usb_ep *ep); 256 int usb_ep_clear_halt(struct usb_ep *ep); 257 int usb_ep_set_wedge(struct usb_ep *ep); 258 int usb_ep_fifo_status(struct usb_ep *ep); 259 void usb_ep_fifo_flush(struct usb_ep *ep); 260 #else 261 static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep, 262 unsigned maxpacket_limit) 263 { } 264 static inline int usb_ep_enable(struct usb_ep *ep) 265 { return 0; } 266 static inline int usb_ep_disable(struct usb_ep *ep) 267 { return 0; } 268 static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, 269 gfp_t gfp_flags) 270 { return NULL; } 271 static inline void usb_ep_free_request(struct usb_ep *ep, 272 struct usb_request *req) 273 { } 274 static inline int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, 275 gfp_t gfp_flags) 276 { return 0; } 277 static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) 278 { return 0; } 279 static inline int usb_ep_set_halt(struct usb_ep *ep) 280 { return 0; } 281 static inline int usb_ep_clear_halt(struct usb_ep *ep) 282 { return 0; } 283 static inline int usb_ep_set_wedge(struct usb_ep *ep) 284 { return 0; } 285 static inline int usb_ep_fifo_status(struct usb_ep *ep) 286 { return 0; } 287 static inline void usb_ep_fifo_flush(struct usb_ep *ep) 288 { } 289 #endif /* USB_GADGET */ 290 291 /*-------------------------------------------------------------------------*/ 292 293 struct usb_dcd_config_params { 294 __u8 bU1devExitLat; /* U1 Device exit Latency */ 295 #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */ 296 __le16 bU2DevExitLat; /* U2 Device exit Latency */ 297 #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */ 298 __u8 besl_baseline; /* Recommended baseline BESL (0-15) */ 299 __u8 besl_deep; /* Recommended deep BESL (0-15) */ 300 #define USB_DEFAULT_BESL_UNSPECIFIED 0xFF /* No recommended value */ 301 }; 302 303 304 struct usb_gadget; 305 struct usb_gadget_driver; 306 struct usb_udc; 307 308 /* the rest of the api to the controller hardware: device operations, 309 * which don't involve endpoints (or i/o). 310 */ 311 struct usb_gadget_ops { 312 int (*get_frame)(struct usb_gadget *); 313 int (*wakeup)(struct usb_gadget *); 314 int (*func_wakeup)(struct usb_gadget *gadget, int intf_id); 315 int (*set_remote_wakeup)(struct usb_gadget *, int set); 316 int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); 317 int (*vbus_session) (struct usb_gadget *, int is_active); 318 int (*vbus_draw) (struct usb_gadget *, unsigned mA); 319 int (*pullup) (struct usb_gadget *, int is_on); 320 int (*ioctl)(struct usb_gadget *, 321 unsigned code, unsigned long param); 322 void (*get_config_params)(struct usb_gadget *, 323 struct usb_dcd_config_params *); 324 int (*udc_start)(struct usb_gadget *, 325 struct usb_gadget_driver *); 326 int (*udc_stop)(struct usb_gadget *); 327 void (*udc_set_speed)(struct usb_gadget *, enum usb_device_speed); 328 void (*udc_set_ssp_rate)(struct usb_gadget *gadget, 329 enum usb_ssp_rate rate); 330 void (*udc_async_callbacks)(struct usb_gadget *gadget, bool enable); 331 struct usb_ep *(*match_ep)(struct usb_gadget *, 332 struct usb_endpoint_descriptor *, 333 struct usb_ss_ep_comp_descriptor *); 334 int (*check_config)(struct usb_gadget *gadget); 335 }; 336 337 /** 338 * struct usb_gadget - represents a usb device 339 * @work: (internal use) Workqueue to be used for sysfs_notify() 340 * @udc: struct usb_udc pointer for this gadget 341 * @ops: Function pointers used to access hardware-specific operations. 342 * @ep0: Endpoint zero, used when reading or writing responses to 343 * driver setup() requests 344 * @ep_list: List of other endpoints supported by the device. 345 * @speed: Speed of current connection to USB host. 346 * @max_speed: Maximal speed the UDC can handle. UDC must support this 347 * and all slower speeds. 348 * @ssp_rate: Current connected SuperSpeed Plus signaling rate and lane count. 349 * @max_ssp_rate: Maximum SuperSpeed Plus signaling rate and lane count the UDC 350 * can handle. The UDC must support this and all slower speeds and lower 351 * number of lanes. 352 * @state: the state we are now (attached, suspended, configured, etc) 353 * @name: Identifies the controller hardware type. Used in diagnostics 354 * and sometimes configuration. 355 * @dev: Driver model state for this abstract device. 356 * @isoch_delay: value from Set Isoch Delay request. Only valid on SS/SSP 357 * @out_epnum: last used out ep number 358 * @in_epnum: last used in ep number 359 * @mA: last set mA value 360 * @otg_caps: OTG capabilities of this gadget. 361 * @sg_supported: true if we can handle scatter-gather 362 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the 363 * gadget driver must provide a USB OTG descriptor. 364 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable 365 * is in the Mini-AB jack, and HNP has been used to switch roles 366 * so that the "A" device currently acts as A-Peripheral, not A-Host. 367 * @a_hnp_support: OTG device feature flag, indicating that the A-Host 368 * supports HNP at this port. 369 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host 370 * only supports HNP on a different root port. 371 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host 372 * enabled HNP support. 373 * @hnp_polling_support: OTG device feature flag, indicating if the OTG device 374 * in peripheral mode can support HNP polling. 375 * @host_request_flag: OTG device feature flag, indicating if A-Peripheral 376 * or B-Peripheral wants to take host role. 377 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to 378 * MaxPacketSize. 379 * @quirk_altset_not_supp: UDC controller doesn't support alt settings. 380 * @quirk_stall_not_supp: UDC controller doesn't support stalling. 381 * @quirk_zlp_not_supp: UDC controller doesn't support ZLP. 382 * @quirk_avoids_skb_reserve: udc/platform wants to avoid skb_reserve() in 383 * u_ether.c to improve performance. 384 * @is_selfpowered: if the gadget is self-powered. 385 * @deactivated: True if gadget is deactivated - in deactivated state it cannot 386 * be connected. 387 * @connected: True if gadget is connected. 388 * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag 389 * indicates that it supports LPM as per the LPM ECN & errata. 390 * @wakeup_capable: True if gadget is capable of sending remote wakeup. 391 * @wakeup_armed: True if gadget is armed by the host for remote wakeup. 392 * @irq: the interrupt number for device controller. 393 * @id_number: a unique ID number for ensuring that gadget names are distinct 394 * 395 * Gadgets have a mostly-portable "gadget driver" implementing device 396 * functions, handling all usb configurations and interfaces. Gadget 397 * drivers talk to hardware-specific code indirectly, through ops vectors. 398 * That insulates the gadget driver from hardware details, and packages 399 * the hardware endpoints through generic i/o queues. The "usb_gadget" 400 * and "usb_ep" interfaces provide that insulation from the hardware. 401 * 402 * Except for the driver data, all fields in this structure are 403 * read-only to the gadget driver. That driver data is part of the 404 * "driver model" infrastructure in 2.6 (and later) kernels, and for 405 * earlier systems is grouped in a similar structure that's not known 406 * to the rest of the kernel. 407 * 408 * Values of the three OTG device feature flags are updated before the 409 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before 410 * driver suspend() calls. They are valid only when is_otg, and when the 411 * device is acting as a B-Peripheral (so is_a_peripheral is false). 412 */ 413 struct usb_gadget { 414 struct work_struct work; 415 struct usb_udc *udc; 416 /* readonly to gadget driver */ 417 const struct usb_gadget_ops *ops; 418 struct usb_ep *ep0; 419 struct list_head ep_list; /* of usb_ep */ 420 enum usb_device_speed speed; 421 enum usb_device_speed max_speed; 422 423 /* USB SuperSpeed Plus only */ 424 enum usb_ssp_rate ssp_rate; 425 enum usb_ssp_rate max_ssp_rate; 426 427 enum usb_device_state state; 428 const char *name; 429 struct device dev; 430 unsigned isoch_delay; 431 unsigned out_epnum; 432 unsigned in_epnum; 433 unsigned mA; 434 struct usb_otg_caps *otg_caps; 435 436 unsigned sg_supported:1; 437 unsigned is_otg:1; 438 unsigned is_a_peripheral:1; 439 unsigned b_hnp_enable:1; 440 unsigned a_hnp_support:1; 441 unsigned a_alt_hnp_support:1; 442 unsigned hnp_polling_support:1; 443 unsigned host_request_flag:1; 444 unsigned quirk_ep_out_aligned_size:1; 445 unsigned quirk_altset_not_supp:1; 446 unsigned quirk_stall_not_supp:1; 447 unsigned quirk_zlp_not_supp:1; 448 unsigned quirk_avoids_skb_reserve:1; 449 unsigned is_selfpowered:1; 450 unsigned deactivated:1; 451 unsigned connected:1; 452 unsigned lpm_capable:1; 453 unsigned wakeup_capable:1; 454 unsigned wakeup_armed:1; 455 int irq; 456 int id_number; 457 }; 458 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work)) 459 460 /* Interface to the device model */ 461 static inline void set_gadget_data(struct usb_gadget *gadget, void *data) 462 { dev_set_drvdata(&gadget->dev, data); } 463 static inline void *get_gadget_data(struct usb_gadget *gadget) 464 { return dev_get_drvdata(&gadget->dev); } 465 static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) 466 { 467 return container_of(dev, struct usb_gadget, dev); 468 } 469 static inline struct usb_gadget *usb_get_gadget(struct usb_gadget *gadget) 470 { 471 get_device(&gadget->dev); 472 return gadget; 473 } 474 static inline void usb_put_gadget(struct usb_gadget *gadget) 475 { 476 put_device(&gadget->dev); 477 } 478 extern void usb_initialize_gadget(struct device *parent, 479 struct usb_gadget *gadget, void (*release)(struct device *dev)); 480 extern int usb_add_gadget(struct usb_gadget *gadget); 481 extern void usb_del_gadget(struct usb_gadget *gadget); 482 483 /* Legacy device-model interface */ 484 extern int usb_add_gadget_udc_release(struct device *parent, 485 struct usb_gadget *gadget, void (*release)(struct device *dev)); 486 extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); 487 extern void usb_del_gadget_udc(struct usb_gadget *gadget); 488 extern char *usb_get_gadget_udc_name(void); 489 490 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ 491 #define gadget_for_each_ep(tmp, gadget) \ 492 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) 493 494 /** 495 * usb_ep_align - returns @len aligned to ep's maxpacketsize. 496 * @ep: the endpoint whose maxpacketsize is used to align @len 497 * @len: buffer size's length to align to @ep's maxpacketsize 498 * 499 * This helper is used to align buffer's size to an ep's maxpacketsize. 500 */ 501 static inline size_t usb_ep_align(struct usb_ep *ep, size_t len) 502 { 503 int max_packet_size = (size_t)usb_endpoint_maxp(ep->desc); 504 505 return round_up(len, max_packet_size); 506 } 507 508 /** 509 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget 510 * requires quirk_ep_out_aligned_size, otherwise returns len. 511 * @g: controller to check for quirk 512 * @ep: the endpoint whose maxpacketsize is used to align @len 513 * @len: buffer size's length to align to @ep's maxpacketsize 514 * 515 * This helper is used in case it's required for any reason to check and maybe 516 * align buffer's size to an ep's maxpacketsize. 517 */ 518 static inline size_t 519 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len) 520 { 521 return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len; 522 } 523 524 /** 525 * gadget_is_altset_supported - return true iff the hardware supports 526 * altsettings 527 * @g: controller to check for quirk 528 */ 529 static inline int gadget_is_altset_supported(struct usb_gadget *g) 530 { 531 return !g->quirk_altset_not_supp; 532 } 533 534 /** 535 * gadget_is_stall_supported - return true iff the hardware supports stalling 536 * @g: controller to check for quirk 537 */ 538 static inline int gadget_is_stall_supported(struct usb_gadget *g) 539 { 540 return !g->quirk_stall_not_supp; 541 } 542 543 /** 544 * gadget_is_zlp_supported - return true iff the hardware supports zlp 545 * @g: controller to check for quirk 546 */ 547 static inline int gadget_is_zlp_supported(struct usb_gadget *g) 548 { 549 return !g->quirk_zlp_not_supp; 550 } 551 552 /** 553 * gadget_avoids_skb_reserve - return true iff the hardware would like to avoid 554 * skb_reserve to improve performance. 555 * @g: controller to check for quirk 556 */ 557 static inline int gadget_avoids_skb_reserve(struct usb_gadget *g) 558 { 559 return g->quirk_avoids_skb_reserve; 560 } 561 562 /** 563 * gadget_is_dualspeed - return true iff the hardware handles high speed 564 * @g: controller that might support both high and full speeds 565 */ 566 static inline int gadget_is_dualspeed(struct usb_gadget *g) 567 { 568 return g->max_speed >= USB_SPEED_HIGH; 569 } 570 571 /** 572 * gadget_is_superspeed() - return true if the hardware handles superspeed 573 * @g: controller that might support superspeed 574 */ 575 static inline int gadget_is_superspeed(struct usb_gadget *g) 576 { 577 return g->max_speed >= USB_SPEED_SUPER; 578 } 579 580 /** 581 * gadget_is_superspeed_plus() - return true if the hardware handles 582 * superspeed plus 583 * @g: controller that might support superspeed plus 584 */ 585 static inline int gadget_is_superspeed_plus(struct usb_gadget *g) 586 { 587 return g->max_speed >= USB_SPEED_SUPER_PLUS; 588 } 589 590 /** 591 * gadget_is_otg - return true iff the hardware is OTG-ready 592 * @g: controller that might have a Mini-AB connector 593 * 594 * This is a runtime test, since kernels with a USB-OTG stack sometimes 595 * run on boards which only have a Mini-B (or Mini-A) connector. 596 */ 597 static inline int gadget_is_otg(struct usb_gadget *g) 598 { 599 #ifdef CONFIG_USB_OTG 600 return g->is_otg; 601 #else 602 return 0; 603 #endif 604 } 605 606 /*-------------------------------------------------------------------------*/ 607 608 #if IS_ENABLED(CONFIG_USB_GADGET) 609 int usb_gadget_frame_number(struct usb_gadget *gadget); 610 int usb_gadget_wakeup(struct usb_gadget *gadget); 611 int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set); 612 int usb_gadget_set_selfpowered(struct usb_gadget *gadget); 613 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget); 614 int usb_gadget_vbus_connect(struct usb_gadget *gadget); 615 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA); 616 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget); 617 int usb_gadget_connect(struct usb_gadget *gadget); 618 int usb_gadget_disconnect(struct usb_gadget *gadget); 619 int usb_gadget_deactivate(struct usb_gadget *gadget); 620 int usb_gadget_activate(struct usb_gadget *gadget); 621 int usb_gadget_check_config(struct usb_gadget *gadget); 622 #else 623 static inline int usb_gadget_frame_number(struct usb_gadget *gadget) 624 { return 0; } 625 static inline int usb_gadget_wakeup(struct usb_gadget *gadget) 626 { return 0; } 627 static inline int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set) 628 { return 0; } 629 static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) 630 { return 0; } 631 static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) 632 { return 0; } 633 static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) 634 { return 0; } 635 static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) 636 { return 0; } 637 static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) 638 { return 0; } 639 static inline int usb_gadget_connect(struct usb_gadget *gadget) 640 { return 0; } 641 static inline int usb_gadget_disconnect(struct usb_gadget *gadget) 642 { return 0; } 643 static inline int usb_gadget_deactivate(struct usb_gadget *gadget) 644 { return 0; } 645 static inline int usb_gadget_activate(struct usb_gadget *gadget) 646 { return 0; } 647 static inline int usb_gadget_check_config(struct usb_gadget *gadget) 648 { return 0; } 649 #endif /* CONFIG_USB_GADGET */ 650 651 /*-------------------------------------------------------------------------*/ 652 653 /** 654 * struct usb_gadget_driver - driver for usb gadget devices 655 * @function: String describing the gadget's function 656 * @max_speed: Highest speed the driver handles. 657 * @setup: Invoked for ep0 control requests that aren't handled by 658 * the hardware level driver. Most calls must be handled by 659 * the gadget driver, including descriptor and configuration 660 * management. The 16 bit members of the setup data are in 661 * USB byte order. Called in_interrupt; this may not sleep. Driver 662 * queues a response to ep0, or returns negative to stall. 663 * @disconnect: Invoked after all transfers have been stopped, 664 * when the host is disconnected. May be called in_interrupt; this 665 * may not sleep. Some devices can't detect disconnect, so this might 666 * not be called except as part of controller shutdown. 667 * @bind: the driver's bind callback 668 * @unbind: Invoked when the driver is unbound from a gadget, 669 * usually from rmmod (after a disconnect is reported). 670 * Called in a context that permits sleeping. 671 * @suspend: Invoked on USB suspend. May be called in_interrupt. 672 * @resume: Invoked on USB resume. May be called in_interrupt. 673 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers 674 * and should be called in_interrupt. 675 * @driver: Driver model state for this driver. 676 * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, 677 * this driver will be bound to any available UDC. 678 * @match_existing_only: If udc is not found, return an error and fail 679 * the driver registration 680 * @is_bound: Allow a driver to be bound to only one gadget 681 * 682 * Devices are disabled till a gadget driver successfully bind()s, which 683 * means the driver will handle setup() requests needed to enumerate (and 684 * meet "chapter 9" requirements) then do some useful work. 685 * 686 * If gadget->is_otg is true, the gadget driver must provide an OTG 687 * descriptor during enumeration, or else fail the bind() call. In such 688 * cases, no USB traffic may flow until both bind() returns without 689 * having called usb_gadget_disconnect(), and the USB host stack has 690 * initialized. 691 * 692 * Drivers use hardware-specific knowledge to configure the usb hardware. 693 * endpoint addressing is only one of several hardware characteristics that 694 * are in descriptors the ep0 implementation returns from setup() calls. 695 * 696 * Except for ep0 implementation, most driver code shouldn't need change to 697 * run on top of different usb controllers. It'll use endpoints set up by 698 * that ep0 implementation. 699 * 700 * The usb controller driver handles a few standard usb requests. Those 701 * include set_address, and feature flags for devices, interfaces, and 702 * endpoints (the get_status, set_feature, and clear_feature requests). 703 * 704 * Accordingly, the driver's setup() callback must always implement all 705 * get_descriptor requests, returning at least a device descriptor and 706 * a configuration descriptor. Drivers must make sure the endpoint 707 * descriptors match any hardware constraints. Some hardware also constrains 708 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). 709 * 710 * The driver's setup() callback must also implement set_configuration, 711 * and should also implement set_interface, get_configuration, and 712 * get_interface. Setting a configuration (or interface) is where 713 * endpoints should be activated or (config 0) shut down. 714 * 715 * The gadget driver's setup() callback does not have to queue a response to 716 * ep0 within the setup() call, the driver can do it after setup() returns. 717 * The UDC driver must wait until such a response is queued before proceeding 718 * with the data/status stages of the control transfer. 719 * 720 * NOTE: Currently, a number of UDC drivers rely on USB_GADGET_DELAYED_STATUS 721 * being returned from the setup() callback, which is a bug. See the comment 722 * next to USB_GADGET_DELAYED_STATUS for details. 723 * 724 * (Note that only the default control endpoint is supported. Neither 725 * hosts nor devices generally support control traffic except to ep0.) 726 * 727 * Most devices will ignore USB suspend/resume operations, and so will 728 * not provide those callbacks. However, some may need to change modes 729 * when the host is not longer directing those activities. For example, 730 * local controls (buttons, dials, etc) may need to be re-enabled since 731 * the (remote) host can't do that any longer; or an error state might 732 * be cleared, to make the device behave identically whether or not 733 * power is maintained. 734 */ 735 struct usb_gadget_driver { 736 char *function; 737 enum usb_device_speed max_speed; 738 int (*bind)(struct usb_gadget *gadget, 739 struct usb_gadget_driver *driver); 740 void (*unbind)(struct usb_gadget *); 741 int (*setup)(struct usb_gadget *, 742 const struct usb_ctrlrequest *); 743 void (*disconnect)(struct usb_gadget *); 744 void (*suspend)(struct usb_gadget *); 745 void (*resume)(struct usb_gadget *); 746 void (*reset)(struct usb_gadget *); 747 748 /* FIXME support safe rmmod */ 749 struct device_driver driver; 750 751 char *udc_name; 752 unsigned match_existing_only:1; 753 bool is_bound:1; 754 }; 755 756 757 758 /*-------------------------------------------------------------------------*/ 759 760 /* driver modules register and unregister, as usual. 761 * these calls must be made in a context that can sleep. 762 * 763 * A gadget driver can be bound to only one gadget at a time. 764 */ 765 766 /** 767 * usb_gadget_register_driver_owner - register a gadget driver 768 * @driver: the driver being registered 769 * @owner: the driver module 770 * @mod_name: the driver module's build name 771 * Context: can sleep 772 * 773 * Call this in your gadget driver's module initialization function, 774 * to tell the underlying UDC controller driver about your driver. 775 * The @bind() function will be called to bind it to a gadget before this 776 * registration call returns. It's expected that the @bind() function will 777 * be in init sections. 778 * 779 * Use the macro defined below instead of calling this directly. 780 */ 781 int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver, 782 struct module *owner, const char *mod_name); 783 784 /* use a define to avoid include chaining to get THIS_MODULE & friends */ 785 #define usb_gadget_register_driver(driver) \ 786 usb_gadget_register_driver_owner(driver, THIS_MODULE, KBUILD_MODNAME) 787 788 /** 789 * usb_gadget_unregister_driver - unregister a gadget driver 790 * @driver:the driver being unregistered 791 * Context: can sleep 792 * 793 * Call this in your gadget driver's module cleanup function, 794 * to tell the underlying usb controller that your driver is 795 * going away. If the controller is connected to a USB host, 796 * it will first disconnect(). The driver is also requested 797 * to unbind() and clean up any device state, before this procedure 798 * finally returns. It's expected that the unbind() functions 799 * will be in exit sections, so may not be linked in some kernels. 800 */ 801 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); 802 803 /*-------------------------------------------------------------------------*/ 804 805 /* utility to simplify dealing with string descriptors */ 806 807 /** 808 * struct usb_string - wraps a C string and its USB id 809 * @id:the (nonzero) ID for this string 810 * @s:the string, in UTF-8 encoding 811 * 812 * If you're using usb_gadget_get_string(), use this to wrap a string 813 * together with its ID. 814 */ 815 struct usb_string { 816 u8 id; 817 const char *s; 818 }; 819 820 /** 821 * struct usb_gadget_strings - a set of USB strings in a given language 822 * @language:identifies the strings' language (0x0409 for en-us) 823 * @strings:array of strings with their ids 824 * 825 * If you're using usb_gadget_get_string(), use this to wrap all the 826 * strings for a given language. 827 */ 828 struct usb_gadget_strings { 829 u16 language; /* 0x0409 for en-us */ 830 struct usb_string *strings; 831 }; 832 833 struct usb_gadget_string_container { 834 struct list_head list; 835 u8 *stash[]; 836 }; 837 838 /* put descriptor for string with that id into buf (buflen >= 256) */ 839 int usb_gadget_get_string(const struct usb_gadget_strings *table, int id, u8 *buf); 840 841 /* check if the given language identifier is valid */ 842 bool usb_validate_langid(u16 langid); 843 844 struct gadget_string { 845 struct config_item item; 846 struct list_head list; 847 char string[USB_MAX_STRING_LEN]; 848 struct usb_string usb_string; 849 }; 850 851 #define to_gadget_string(str_item)\ 852 container_of(str_item, struct gadget_string, item) 853 854 /*-------------------------------------------------------------------------*/ 855 856 /* utility to simplify managing config descriptors */ 857 858 /* write vector of descriptors into buffer */ 859 int usb_descriptor_fillbuf(void *, unsigned, 860 const struct usb_descriptor_header **); 861 862 /* build config descriptor from single descriptor vector */ 863 int usb_gadget_config_buf(const struct usb_config_descriptor *config, 864 void *buf, unsigned buflen, const struct usb_descriptor_header **desc); 865 866 /* copy a NULL-terminated vector of descriptors */ 867 struct usb_descriptor_header **usb_copy_descriptors( 868 struct usb_descriptor_header **); 869 870 /** 871 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors() 872 * @v: vector of descriptors 873 */ 874 static inline void usb_free_descriptors(struct usb_descriptor_header **v) 875 { 876 kfree(v); 877 } 878 879 struct usb_function; 880 int usb_assign_descriptors(struct usb_function *f, 881 struct usb_descriptor_header **fs, 882 struct usb_descriptor_header **hs, 883 struct usb_descriptor_header **ss, 884 struct usb_descriptor_header **ssp); 885 void usb_free_all_descriptors(struct usb_function *f); 886 887 struct usb_descriptor_header *usb_otg_descriptor_alloc( 888 struct usb_gadget *gadget); 889 int usb_otg_descriptor_init(struct usb_gadget *gadget, 890 struct usb_descriptor_header *otg_desc); 891 /*-------------------------------------------------------------------------*/ 892 893 /* utility to simplify map/unmap of usb_requests to/from DMA */ 894 895 #ifdef CONFIG_HAS_DMA 896 extern int usb_gadget_map_request_by_dev(struct device *dev, 897 struct usb_request *req, int is_in); 898 extern int usb_gadget_map_request(struct usb_gadget *gadget, 899 struct usb_request *req, int is_in); 900 901 extern void usb_gadget_unmap_request_by_dev(struct device *dev, 902 struct usb_request *req, int is_in); 903 extern void usb_gadget_unmap_request(struct usb_gadget *gadget, 904 struct usb_request *req, int is_in); 905 #else /* !CONFIG_HAS_DMA */ 906 static inline int usb_gadget_map_request_by_dev(struct device *dev, 907 struct usb_request *req, int is_in) { return -ENOSYS; } 908 static inline int usb_gadget_map_request(struct usb_gadget *gadget, 909 struct usb_request *req, int is_in) { return -ENOSYS; } 910 911 static inline void usb_gadget_unmap_request_by_dev(struct device *dev, 912 struct usb_request *req, int is_in) { } 913 static inline void usb_gadget_unmap_request(struct usb_gadget *gadget, 914 struct usb_request *req, int is_in) { } 915 #endif /* !CONFIG_HAS_DMA */ 916 917 /*-------------------------------------------------------------------------*/ 918 919 /* utility to set gadget state properly */ 920 921 extern void usb_gadget_set_state(struct usb_gadget *gadget, 922 enum usb_device_state state); 923 924 /*-------------------------------------------------------------------------*/ 925 926 /* utility to tell udc core that the bus reset occurs */ 927 extern void usb_gadget_udc_reset(struct usb_gadget *gadget, 928 struct usb_gadget_driver *driver); 929 930 /*-------------------------------------------------------------------------*/ 931 932 /* utility to give requests back to the gadget layer */ 933 934 extern void usb_gadget_giveback_request(struct usb_ep *ep, 935 struct usb_request *req); 936 937 /*-------------------------------------------------------------------------*/ 938 939 /* utility to find endpoint by name */ 940 941 extern struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, 942 const char *name); 943 944 /*-------------------------------------------------------------------------*/ 945 946 /* utility to check if endpoint caps match descriptor needs */ 947 948 extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget, 949 struct usb_ep *ep, struct usb_endpoint_descriptor *desc, 950 struct usb_ss_ep_comp_descriptor *ep_comp); 951 952 /*-------------------------------------------------------------------------*/ 953 954 /* utility to update vbus status for udc core, it may be scheduled */ 955 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status); 956 957 /*-------------------------------------------------------------------------*/ 958 959 /* utility wrapping a simple endpoint selection policy */ 960 961 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, 962 struct usb_endpoint_descriptor *); 963 964 965 extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *, 966 struct usb_endpoint_descriptor *, 967 struct usb_ss_ep_comp_descriptor *); 968 969 extern void usb_ep_autoconfig_release(struct usb_ep *); 970 971 extern void usb_ep_autoconfig_reset(struct usb_gadget *); 972 973 #endif /* __LINUX_USB_GADGET_H */ 974