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/cleanup.h> 19 #include <linux/configfs.h> 20 #include <linux/device.h> 21 #include <linux/errno.h> 22 #include <linux/init.h> 23 #include <linux/list.h> 24 #include <linux/slab.h> 25 #include <linux/scatterlist.h> 26 #include <linux/types.h> 27 #include <linux/workqueue.h> 28 #include <linux/usb/ch9.h> 29 30 #define UDC_TRACE_STR_MAX 512 31 32 struct usb_ep; 33 34 /** 35 * struct usb_request - describes one i/o request 36 * @ep: The associated endpoint set by usb_ep_alloc_request(). 37 * @buf: Buffer used for data. Always provide this; some controllers 38 * only use PIO, or don't use DMA for some endpoints. 39 * @dma: DMA address corresponding to 'buf'. If you don't set this 40 * field, and the usb controller needs one, it is responsible 41 * for mapping and unmapping the buffer. 42 * @sg: a scatterlist for SG-capable controllers. 43 * @num_sgs: number of SG entries 44 * @num_mapped_sgs: number of SG entries mapped to DMA (internal) 45 * @length: Length of that data 46 * @stream_id: The stream id, when USB3.0 bulk streams are being used 47 * @is_last: Indicates if this is the last request of a stream_id before 48 * switching to a different stream (required for DWC3 controllers). 49 * @no_interrupt: If true, hints that no completion irq is needed. 50 * Helpful sometimes with deep request queues that are handled 51 * directly by DMA controllers. 52 * @zero: If true, when writing data, makes the last packet be "short" 53 * by adding a zero length packet as needed; 54 * @short_not_ok: When reading data, makes short packets be 55 * treated as errors (queue stops advancing till cleanup). 56 * @dma_mapped: Indicates if request has been mapped to DMA (internal) 57 * @sg_was_mapped: Set if the scatterlist has been mapped before the request 58 * @complete: Function called when request completes, so this request and 59 * its buffer may be re-used. The function will always be called with 60 * interrupts disabled, and it must not sleep. 61 * Reads terminate with a short packet, or when the buffer fills, 62 * whichever comes first. When writes terminate, some data bytes 63 * will usually still be in flight (often in a hardware fifo). 64 * Errors (for reads or writes) stop the queue from advancing 65 * until the completion function returns, so that any transfers 66 * invalidated by the error may first be dequeued. 67 * @context: For use by the completion callback 68 * @list: For use by the gadget driver. 69 * @frame_number: Reports the interval number in (micro)frame in which the 70 * isochronous transfer was transmitted or received. 71 * @status: Reports completion code, zero or a negative errno. 72 * Normally, faults block the transfer queue from advancing until 73 * the completion callback returns. 74 * Code "-ESHUTDOWN" indicates completion caused by device disconnect, 75 * or when the driver disabled the endpoint. 76 * @actual: Reports bytes transferred to/from the buffer. For reads (OUT 77 * transfers) this may be less than the requested length. If the 78 * short_not_ok flag is set, short reads are treated as errors 79 * even when status otherwise indicates successful completion. 80 * Note that for writes (IN transfers) some data bytes may still 81 * reside in a device-side FIFO when the request is reported as 82 * complete. 83 * 84 * These are allocated/freed through the endpoint they're used with. The 85 * hardware's driver can add extra per-request data to the memory it returns, 86 * which often avoids separate memory allocations (potential failures), 87 * later when the request is queued. 88 * 89 * Request flags affect request handling, such as whether a zero length 90 * packet is written (the "zero" flag), whether a short read should be 91 * treated as an error (blocking request queue advance, the "short_not_ok" 92 * flag), or hinting that an interrupt is not required (the "no_interrupt" 93 * flag, for use with deep request queues). 94 * 95 * Bulk endpoints can use any size buffers, and can also be used for interrupt 96 * transfers. interrupt-only endpoints can be much less functional. 97 * 98 * NOTE: this is analogous to 'struct urb' on the host side, except that 99 * it's thinner and promotes more pre-allocation. 100 */ 101 102 struct usb_request { 103 struct usb_ep *ep; 104 void *buf; 105 unsigned length; 106 dma_addr_t dma; 107 108 struct scatterlist *sg; 109 unsigned num_sgs; 110 unsigned num_mapped_sgs; 111 112 unsigned stream_id:16; 113 unsigned is_last:1; 114 unsigned no_interrupt:1; 115 unsigned zero:1; 116 unsigned short_not_ok:1; 117 unsigned dma_mapped:1; 118 unsigned sg_was_mapped:1; 119 120 void (*complete)(struct usb_ep *ep, 121 struct usb_request *req); 122 void *context; 123 struct list_head list; 124 125 unsigned frame_number; /* ISO ONLY */ 126 127 int status; 128 unsigned actual; 129 }; 130 131 /*-------------------------------------------------------------------------*/ 132 133 /* endpoint-specific parts of the api to the usb controller hardware. 134 * unlike the urb model, (de)multiplexing layers are not required. 135 * (so this api could slash overhead if used on the host side...) 136 * 137 * note that device side usb controllers commonly differ in how many 138 * endpoints they support, as well as their capabilities. 139 */ 140 struct usb_ep_ops { 141 int (*enable) (struct usb_ep *ep, 142 const struct usb_endpoint_descriptor *desc); 143 int (*disable) (struct usb_ep *ep); 144 void (*dispose) (struct usb_ep *ep); 145 146 struct usb_request *(*alloc_request) (struct usb_ep *ep, 147 gfp_t gfp_flags); 148 void (*free_request) (struct usb_ep *ep, struct usb_request *req); 149 150 int (*queue) (struct usb_ep *ep, struct usb_request *req, 151 gfp_t gfp_flags); 152 int (*dequeue) (struct usb_ep *ep, struct usb_request *req); 153 154 int (*set_halt) (struct usb_ep *ep, int value); 155 int (*set_wedge) (struct usb_ep *ep); 156 157 int (*fifo_status) (struct usb_ep *ep); 158 void (*fifo_flush) (struct usb_ep *ep); 159 }; 160 161 /** 162 * struct usb_ep_caps - endpoint capabilities description 163 * @type_control:Endpoint supports control type (reserved for ep0). 164 * @type_iso:Endpoint supports isochronous transfers. 165 * @type_bulk:Endpoint supports bulk transfers. 166 * @type_int:Endpoint supports interrupt transfers. 167 * @dir_in:Endpoint supports IN direction. 168 * @dir_out:Endpoint supports OUT direction. 169 */ 170 struct usb_ep_caps { 171 unsigned type_control:1; 172 unsigned type_iso:1; 173 unsigned type_bulk:1; 174 unsigned type_int:1; 175 unsigned dir_in:1; 176 unsigned dir_out:1; 177 }; 178 179 #define USB_EP_CAPS_TYPE_CONTROL 0x01 180 #define USB_EP_CAPS_TYPE_ISO 0x02 181 #define USB_EP_CAPS_TYPE_BULK 0x04 182 #define USB_EP_CAPS_TYPE_INT 0x08 183 #define USB_EP_CAPS_TYPE_ALL \ 184 (USB_EP_CAPS_TYPE_ISO | USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT) 185 #define USB_EP_CAPS_DIR_IN 0x01 186 #define USB_EP_CAPS_DIR_OUT 0x02 187 #define USB_EP_CAPS_DIR_ALL (USB_EP_CAPS_DIR_IN | USB_EP_CAPS_DIR_OUT) 188 189 #define USB_EP_CAPS(_type, _dir) \ 190 { \ 191 .type_control = !!(_type & USB_EP_CAPS_TYPE_CONTROL), \ 192 .type_iso = !!(_type & USB_EP_CAPS_TYPE_ISO), \ 193 .type_bulk = !!(_type & USB_EP_CAPS_TYPE_BULK), \ 194 .type_int = !!(_type & USB_EP_CAPS_TYPE_INT), \ 195 .dir_in = !!(_dir & USB_EP_CAPS_DIR_IN), \ 196 .dir_out = !!(_dir & USB_EP_CAPS_DIR_OUT), \ 197 } 198 199 /** 200 * struct usb_ep - device side representation of USB endpoint 201 * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk" 202 * @ops: Function pointers used to access hardware-specific operations. 203 * @ep_list:the gadget's ep_list holds all of its endpoints 204 * @caps:The structure describing types and directions supported by endpoint. 205 * @enabled: The current endpoint enabled/disabled state. 206 * @claimed: True if this endpoint is claimed by a function. 207 * @maxpacket:The maximum packet size used on this endpoint. The initial 208 * value can sometimes be reduced (hardware allowing), according to 209 * the endpoint descriptor used to configure the endpoint. 210 * @maxpacket_limit:The maximum packet size value which can be handled by this 211 * endpoint. It's set once by UDC driver when endpoint is initialized, and 212 * should not be changed. Should not be confused with maxpacket. 213 * @max_streams: The maximum number of streams supported 214 * by this EP (0 - 16, actual number is 2^n) 215 * @mult: multiplier, 'mult' value for SS Isoc EPs 216 * @maxburst: the maximum number of bursts supported by this EP (for usb3) 217 * @driver_data:for use by the gadget driver. 218 * @address: used to identify the endpoint when finding descriptor that 219 * matches connection speed 220 * @desc: endpoint descriptor. This pointer is set before the endpoint is 221 * enabled and remains valid until the endpoint is disabled. 222 * @comp_desc: In case of SuperSpeed support, this is the endpoint companion 223 * descriptor that is used to configure the endpoint 224 * 225 * the bus controller driver lists all the general purpose endpoints in 226 * gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, 227 * and is accessed only in response to a driver setup() callback. 228 */ 229 230 struct usb_ep { 231 void *driver_data; 232 233 const char *name; 234 const struct usb_ep_ops *ops; 235 const struct usb_endpoint_descriptor *desc; 236 const struct usb_ss_ep_comp_descriptor *comp_desc; 237 struct list_head ep_list; 238 struct usb_ep_caps caps; 239 bool claimed; 240 bool enabled; 241 unsigned mult:2; 242 unsigned maxburst:5; 243 u8 address; 244 u16 maxpacket; 245 u16 maxpacket_limit; 246 u16 max_streams; 247 }; 248 249 /*-------------------------------------------------------------------------*/ 250 251 #if IS_ENABLED(CONFIG_USB_GADGET) 252 void usb_ep_set_maxpacket_limit(struct usb_ep *ep, unsigned maxpacket_limit); 253 int usb_ep_enable(struct usb_ep *ep); 254 int usb_ep_disable(struct usb_ep *ep); 255 struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags); 256 void usb_ep_free_request(struct usb_ep *ep, struct usb_request *req); 257 int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags); 258 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req); 259 int usb_ep_set_halt(struct usb_ep *ep); 260 int usb_ep_clear_halt(struct usb_ep *ep); 261 int usb_ep_set_wedge(struct usb_ep *ep); 262 int usb_ep_fifo_status(struct usb_ep *ep); 263 void usb_ep_fifo_flush(struct usb_ep *ep); 264 #else 265 static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep, 266 unsigned maxpacket_limit) 267 { } 268 static inline int usb_ep_enable(struct usb_ep *ep) 269 { return 0; } 270 static inline int usb_ep_disable(struct usb_ep *ep) 271 { return 0; } 272 static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep, 273 gfp_t gfp_flags) 274 { return NULL; } 275 static inline void usb_ep_free_request(struct usb_ep *ep, 276 struct usb_request *req) 277 { } 278 static inline int usb_ep_queue(struct usb_ep *ep, struct usb_request *req, 279 gfp_t gfp_flags) 280 { return 0; } 281 static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req) 282 { return 0; } 283 static inline int usb_ep_set_halt(struct usb_ep *ep) 284 { return 0; } 285 static inline int usb_ep_clear_halt(struct usb_ep *ep) 286 { return 0; } 287 static inline int usb_ep_set_wedge(struct usb_ep *ep) 288 { return 0; } 289 static inline int usb_ep_fifo_status(struct usb_ep *ep) 290 { return 0; } 291 static inline void usb_ep_fifo_flush(struct usb_ep *ep) 292 { } 293 #endif /* USB_GADGET */ 294 295 /*-------------------------------------------------------------------------*/ 296 297 /** 298 * free_usb_request - frees a usb_request object and its buffer 299 * @req: the request being freed 300 * 301 * This helper function frees both the request's buffer and the request object 302 * itself by calling usb_ep_free_request(). Its signature is designed to be used 303 * with DEFINE_FREE() to enable automatic, scope-based cleanup for usb_request 304 * pointers. 305 */ 306 static inline void free_usb_request(struct usb_request *req) 307 { 308 if (!req) 309 return; 310 311 kfree(req->buf); 312 usb_ep_free_request(req->ep, req); 313 } 314 315 DEFINE_FREE(free_usb_request, struct usb_request *, free_usb_request(_T)) 316 317 /*-------------------------------------------------------------------------*/ 318 319 struct usb_dcd_config_params { 320 __u8 bU1devExitLat; /* U1 Device exit Latency */ 321 #define USB_DEFAULT_U1_DEV_EXIT_LAT 0x01 /* Less then 1 microsec */ 322 __le16 bU2DevExitLat; /* U2 Device exit Latency */ 323 #define USB_DEFAULT_U2_DEV_EXIT_LAT 0x1F4 /* Less then 500 microsec */ 324 __u8 besl_baseline; /* Recommended baseline BESL (0-15) */ 325 __u8 besl_deep; /* Recommended deep BESL (0-15) */ 326 #define USB_DEFAULT_BESL_UNSPECIFIED 0xFF /* No recommended value */ 327 }; 328 329 330 struct usb_gadget; 331 struct usb_gadget_driver; 332 struct usb_udc; 333 334 /* the rest of the api to the controller hardware: device operations, 335 * which don't involve endpoints (or i/o). 336 */ 337 struct usb_gadget_ops { 338 int (*get_frame)(struct usb_gadget *); 339 int (*wakeup)(struct usb_gadget *); 340 int (*func_wakeup)(struct usb_gadget *gadget, int intf_id); 341 int (*set_remote_wakeup)(struct usb_gadget *, int set); 342 int (*set_selfpowered) (struct usb_gadget *, int is_selfpowered); 343 int (*vbus_session) (struct usb_gadget *, int is_active); 344 int (*vbus_draw) (struct usb_gadget *, unsigned mA); 345 int (*pullup) (struct usb_gadget *, int is_on); 346 int (*ioctl)(struct usb_gadget *, 347 unsigned code, unsigned long param); 348 void (*get_config_params)(struct usb_gadget *, 349 struct usb_dcd_config_params *); 350 int (*udc_start)(struct usb_gadget *, 351 struct usb_gadget_driver *); 352 int (*udc_stop)(struct usb_gadget *); 353 void (*udc_set_speed)(struct usb_gadget *, enum usb_device_speed); 354 void (*udc_set_ssp_rate)(struct usb_gadget *gadget, 355 enum usb_ssp_rate rate); 356 void (*udc_async_callbacks)(struct usb_gadget *gadget, bool enable); 357 struct usb_ep *(*match_ep)(struct usb_gadget *, 358 struct usb_endpoint_descriptor *, 359 struct usb_ss_ep_comp_descriptor *); 360 int (*check_config)(struct usb_gadget *gadget); 361 }; 362 363 /** 364 * struct usb_gadget - represents a usb device 365 * @work: (internal use) Workqueue to be used for sysfs_notify() 366 * @udc: struct usb_udc pointer for this gadget 367 * @ops: Function pointers used to access hardware-specific operations. 368 * @ep0: Endpoint zero, used when reading or writing responses to 369 * driver setup() requests 370 * @ep_list: List of other endpoints supported by the device. 371 * @speed: Speed of current connection to USB host. 372 * @max_speed: Maximal speed the UDC can handle. UDC must support this 373 * and all slower speeds. 374 * @ssp_rate: Current connected SuperSpeed Plus signaling rate and lane count. 375 * @max_ssp_rate: Maximum SuperSpeed Plus signaling rate and lane count the UDC 376 * can handle. The UDC must support this and all slower speeds and lower 377 * number of lanes. 378 * @state: the state we are now (attached, suspended, configured, etc) 379 * @name: Identifies the controller hardware type. Used in diagnostics 380 * and sometimes configuration. 381 * @dev: Driver model state for this abstract device. 382 * @isoch_delay: value from Set Isoch Delay request. Only valid on SS/SSP 383 * @out_epnum: last used out ep number 384 * @in_epnum: last used in ep number 385 * @mA: last set mA value 386 * @otg_caps: OTG capabilities of this gadget. 387 * @sg_supported: true if we can handle scatter-gather 388 * @is_otg: True if the USB device port uses a Mini-AB jack, so that the 389 * gadget driver must provide a USB OTG descriptor. 390 * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable 391 * is in the Mini-AB jack, and HNP has been used to switch roles 392 * so that the "A" device currently acts as A-Peripheral, not A-Host. 393 * @a_hnp_support: OTG device feature flag, indicating that the A-Host 394 * supports HNP at this port. 395 * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host 396 * only supports HNP on a different root port. 397 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host 398 * enabled HNP support. 399 * @hnp_polling_support: OTG device feature flag, indicating if the OTG device 400 * in peripheral mode can support HNP polling. 401 * @host_request_flag: OTG device feature flag, indicating if A-Peripheral 402 * or B-Peripheral wants to take host role. 403 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to 404 * MaxPacketSize. 405 * @quirk_altset_not_supp: UDC controller doesn't support alt settings. 406 * @quirk_stall_not_supp: UDC controller doesn't support stalling. 407 * @quirk_zlp_not_supp: UDC controller doesn't support ZLP. 408 * @quirk_avoids_skb_reserve: udc/platform wants to avoid skb_reserve() in 409 * u_ether.c to improve performance. 410 * @is_selfpowered: if the gadget is self-powered. 411 * @deactivated: True if gadget is deactivated - in deactivated state it cannot 412 * be connected. 413 * @connected: True if gadget is connected. 414 * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag 415 * indicates that it supports LPM as per the LPM ECN & errata. 416 * @wakeup_capable: True if gadget is capable of sending remote wakeup. 417 * @wakeup_armed: True if gadget is armed by the host for remote wakeup. 418 * @irq: the interrupt number for device controller. 419 * @id_number: a unique ID number for ensuring that gadget names are distinct 420 * 421 * Gadgets have a mostly-portable "gadget driver" implementing device 422 * functions, handling all usb configurations and interfaces. Gadget 423 * drivers talk to hardware-specific code indirectly, through ops vectors. 424 * That insulates the gadget driver from hardware details, and packages 425 * the hardware endpoints through generic i/o queues. The "usb_gadget" 426 * and "usb_ep" interfaces provide that insulation from the hardware. 427 * 428 * Except for the driver data, all fields in this structure are 429 * read-only to the gadget driver. That driver data is part of the 430 * "driver model" infrastructure in 2.6 (and later) kernels, and for 431 * earlier systems is grouped in a similar structure that's not known 432 * to the rest of the kernel. 433 * 434 * Values of the three OTG device feature flags are updated before the 435 * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before 436 * driver suspend() calls. They are valid only when is_otg, and when the 437 * device is acting as a B-Peripheral (so is_a_peripheral is false). 438 */ 439 struct usb_gadget { 440 struct work_struct work; 441 struct usb_udc *udc; 442 /* readonly to gadget driver */ 443 const struct usb_gadget_ops *ops; 444 struct usb_ep *ep0; 445 struct list_head ep_list; /* of usb_ep */ 446 enum usb_device_speed speed; 447 enum usb_device_speed max_speed; 448 449 /* USB SuperSpeed Plus only */ 450 enum usb_ssp_rate ssp_rate; 451 enum usb_ssp_rate max_ssp_rate; 452 453 enum usb_device_state state; 454 const char *name; 455 struct device dev; 456 unsigned isoch_delay; 457 unsigned out_epnum; 458 unsigned in_epnum; 459 unsigned mA; 460 struct usb_otg_caps *otg_caps; 461 462 unsigned sg_supported:1; 463 unsigned is_otg:1; 464 unsigned is_a_peripheral:1; 465 unsigned b_hnp_enable:1; 466 unsigned a_hnp_support:1; 467 unsigned a_alt_hnp_support:1; 468 unsigned hnp_polling_support:1; 469 unsigned host_request_flag:1; 470 unsigned quirk_ep_out_aligned_size:1; 471 unsigned quirk_altset_not_supp:1; 472 unsigned quirk_stall_not_supp:1; 473 unsigned quirk_zlp_not_supp:1; 474 unsigned quirk_avoids_skb_reserve:1; 475 unsigned is_selfpowered:1; 476 unsigned deactivated:1; 477 unsigned connected:1; 478 unsigned lpm_capable:1; 479 unsigned wakeup_capable:1; 480 unsigned wakeup_armed:1; 481 int irq; 482 int id_number; 483 }; 484 #define work_to_gadget(w) (container_of((w), struct usb_gadget, work)) 485 486 /* Interface to the device model */ 487 static inline void set_gadget_data(struct usb_gadget *gadget, void *data) 488 { dev_set_drvdata(&gadget->dev, data); } 489 static inline void *get_gadget_data(struct usb_gadget *gadget) 490 { return dev_get_drvdata(&gadget->dev); } 491 static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev) 492 { 493 return container_of(dev, struct usb_gadget, dev); 494 } 495 static inline struct usb_gadget *usb_get_gadget(struct usb_gadget *gadget) 496 { 497 get_device(&gadget->dev); 498 return gadget; 499 } 500 static inline void usb_put_gadget(struct usb_gadget *gadget) 501 { 502 put_device(&gadget->dev); 503 } 504 extern void usb_initialize_gadget(struct device *parent, 505 struct usb_gadget *gadget, void (*release)(struct device *dev)); 506 extern int usb_add_gadget(struct usb_gadget *gadget); 507 extern void usb_del_gadget(struct usb_gadget *gadget); 508 509 /* Legacy device-model interface */ 510 extern int usb_add_gadget_udc_release(struct device *parent, 511 struct usb_gadget *gadget, void (*release)(struct device *dev)); 512 extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget); 513 extern void usb_del_gadget_udc(struct usb_gadget *gadget); 514 extern char *usb_get_gadget_udc_name(void); 515 516 /* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */ 517 #define gadget_for_each_ep(tmp, gadget) \ 518 list_for_each_entry(tmp, &(gadget)->ep_list, ep_list) 519 520 /** 521 * usb_ep_align - returns @len aligned to ep's maxpacketsize. 522 * @ep: the endpoint whose maxpacketsize is used to align @len 523 * @len: buffer size's length to align to @ep's maxpacketsize 524 * 525 * This helper is used to align buffer's size to an ep's maxpacketsize. 526 */ 527 static inline size_t usb_ep_align(struct usb_ep *ep, size_t len) 528 { 529 int max_packet_size = (size_t)usb_endpoint_maxp(ep->desc); 530 531 return round_up(len, max_packet_size); 532 } 533 534 /** 535 * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget 536 * requires quirk_ep_out_aligned_size, otherwise returns len. 537 * @g: controller to check for quirk 538 * @ep: the endpoint whose maxpacketsize is used to align @len 539 * @len: buffer size's length to align to @ep's maxpacketsize 540 * 541 * This helper is used in case it's required for any reason to check and maybe 542 * align buffer's size to an ep's maxpacketsize. 543 */ 544 static inline size_t 545 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len) 546 { 547 return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len; 548 } 549 550 /** 551 * gadget_is_altset_supported - return true iff the hardware supports 552 * altsettings 553 * @g: controller to check for quirk 554 */ 555 static inline int gadget_is_altset_supported(struct usb_gadget *g) 556 { 557 return !g->quirk_altset_not_supp; 558 } 559 560 /** 561 * gadget_is_stall_supported - return true iff the hardware supports stalling 562 * @g: controller to check for quirk 563 */ 564 static inline int gadget_is_stall_supported(struct usb_gadget *g) 565 { 566 return !g->quirk_stall_not_supp; 567 } 568 569 /** 570 * gadget_is_zlp_supported - return true iff the hardware supports zlp 571 * @g: controller to check for quirk 572 */ 573 static inline int gadget_is_zlp_supported(struct usb_gadget *g) 574 { 575 return !g->quirk_zlp_not_supp; 576 } 577 578 /** 579 * gadget_avoids_skb_reserve - return true iff the hardware would like to avoid 580 * skb_reserve to improve performance. 581 * @g: controller to check for quirk 582 */ 583 static inline int gadget_avoids_skb_reserve(struct usb_gadget *g) 584 { 585 return g->quirk_avoids_skb_reserve; 586 } 587 588 /** 589 * gadget_is_dualspeed - return true iff the hardware handles high speed 590 * @g: controller that might support both high and full speeds 591 */ 592 static inline int gadget_is_dualspeed(struct usb_gadget *g) 593 { 594 return g->max_speed >= USB_SPEED_HIGH; 595 } 596 597 /** 598 * gadget_is_superspeed() - return true if the hardware handles superspeed 599 * @g: controller that might support superspeed 600 */ 601 static inline int gadget_is_superspeed(struct usb_gadget *g) 602 { 603 return g->max_speed >= USB_SPEED_SUPER; 604 } 605 606 /** 607 * gadget_is_superspeed_plus() - return true if the hardware handles 608 * superspeed plus 609 * @g: controller that might support superspeed plus 610 */ 611 static inline int gadget_is_superspeed_plus(struct usb_gadget *g) 612 { 613 return g->max_speed >= USB_SPEED_SUPER_PLUS; 614 } 615 616 /** 617 * gadget_is_otg - return true iff the hardware is OTG-ready 618 * @g: controller that might have a Mini-AB connector 619 * 620 * This is a runtime test, since kernels with a USB-OTG stack sometimes 621 * run on boards which only have a Mini-B (or Mini-A) connector. 622 */ 623 static inline int gadget_is_otg(struct usb_gadget *g) 624 { 625 #ifdef CONFIG_USB_OTG 626 return g->is_otg; 627 #else 628 return 0; 629 #endif 630 } 631 632 /*-------------------------------------------------------------------------*/ 633 634 #if IS_ENABLED(CONFIG_USB_GADGET) 635 int usb_gadget_frame_number(struct usb_gadget *gadget); 636 int usb_gadget_wakeup(struct usb_gadget *gadget); 637 int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set); 638 int usb_gadget_set_selfpowered(struct usb_gadget *gadget); 639 int usb_gadget_clear_selfpowered(struct usb_gadget *gadget); 640 int usb_gadget_vbus_connect(struct usb_gadget *gadget); 641 int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA); 642 int usb_gadget_vbus_disconnect(struct usb_gadget *gadget); 643 int usb_gadget_connect(struct usb_gadget *gadget); 644 int usb_gadget_disconnect(struct usb_gadget *gadget); 645 int usb_gadget_deactivate(struct usb_gadget *gadget); 646 int usb_gadget_activate(struct usb_gadget *gadget); 647 int usb_gadget_check_config(struct usb_gadget *gadget); 648 #else 649 static inline int usb_gadget_frame_number(struct usb_gadget *gadget) 650 { return 0; } 651 static inline int usb_gadget_wakeup(struct usb_gadget *gadget) 652 { return 0; } 653 static inline int usb_gadget_set_remote_wakeup(struct usb_gadget *gadget, int set) 654 { return 0; } 655 static inline int usb_gadget_set_selfpowered(struct usb_gadget *gadget) 656 { return 0; } 657 static inline int usb_gadget_clear_selfpowered(struct usb_gadget *gadget) 658 { return 0; } 659 static inline int usb_gadget_vbus_connect(struct usb_gadget *gadget) 660 { return 0; } 661 static inline int usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA) 662 { return 0; } 663 static inline int usb_gadget_vbus_disconnect(struct usb_gadget *gadget) 664 { return 0; } 665 static inline int usb_gadget_connect(struct usb_gadget *gadget) 666 { return 0; } 667 static inline int usb_gadget_disconnect(struct usb_gadget *gadget) 668 { return 0; } 669 static inline int usb_gadget_deactivate(struct usb_gadget *gadget) 670 { return 0; } 671 static inline int usb_gadget_activate(struct usb_gadget *gadget) 672 { return 0; } 673 static inline int usb_gadget_check_config(struct usb_gadget *gadget) 674 { return 0; } 675 #endif /* CONFIG_USB_GADGET */ 676 677 /*-------------------------------------------------------------------------*/ 678 679 /** 680 * struct usb_gadget_driver - driver for usb gadget devices 681 * @function: String describing the gadget's function 682 * @max_speed: Highest speed the driver handles. 683 * @setup: Invoked for ep0 control requests that aren't handled by 684 * the hardware level driver. Most calls must be handled by 685 * the gadget driver, including descriptor and configuration 686 * management. The 16 bit members of the setup data are in 687 * USB byte order. Called in_interrupt; this may not sleep. Driver 688 * queues a response to ep0, or returns negative to stall. 689 * @disconnect: Invoked after all transfers have been stopped, 690 * when the host is disconnected. May be called in_interrupt; this 691 * may not sleep. Some devices can't detect disconnect, so this might 692 * not be called except as part of controller shutdown. 693 * @bind: the driver's bind callback 694 * @unbind: Invoked when the driver is unbound from a gadget, 695 * usually from rmmod (after a disconnect is reported). 696 * Called in a context that permits sleeping. 697 * @suspend: Invoked on USB suspend. May be called in_interrupt. 698 * @resume: Invoked on USB resume. May be called in_interrupt. 699 * @reset: Invoked on USB bus reset. It is mandatory for all gadget drivers 700 * and should be called in_interrupt. 701 * @driver: Driver model state for this driver. 702 * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, 703 * this driver will be bound to any available UDC. 704 * @match_existing_only: If udc is not found, return an error and fail 705 * the driver registration 706 * @is_bound: Allow a driver to be bound to only one gadget 707 * 708 * Devices are disabled till a gadget driver successfully bind()s, which 709 * means the driver will handle setup() requests needed to enumerate (and 710 * meet "chapter 9" requirements) then do some useful work. 711 * 712 * If gadget->is_otg is true, the gadget driver must provide an OTG 713 * descriptor during enumeration, or else fail the bind() call. In such 714 * cases, no USB traffic may flow until both bind() returns without 715 * having called usb_gadget_disconnect(), and the USB host stack has 716 * initialized. 717 * 718 * Drivers use hardware-specific knowledge to configure the usb hardware. 719 * endpoint addressing is only one of several hardware characteristics that 720 * are in descriptors the ep0 implementation returns from setup() calls. 721 * 722 * Except for ep0 implementation, most driver code shouldn't need change to 723 * run on top of different usb controllers. It'll use endpoints set up by 724 * that ep0 implementation. 725 * 726 * The usb controller driver handles a few standard usb requests. Those 727 * include set_address, and feature flags for devices, interfaces, and 728 * endpoints (the get_status, set_feature, and clear_feature requests). 729 * 730 * Accordingly, the driver's setup() callback must always implement all 731 * get_descriptor requests, returning at least a device descriptor and 732 * a configuration descriptor. Drivers must make sure the endpoint 733 * descriptors match any hardware constraints. Some hardware also constrains 734 * other descriptors. (The pxa250 allows only configurations 1, 2, or 3). 735 * 736 * The driver's setup() callback must also implement set_configuration, 737 * and should also implement set_interface, get_configuration, and 738 * get_interface. Setting a configuration (or interface) is where 739 * endpoints should be activated or (config 0) shut down. 740 * 741 * The gadget driver's setup() callback does not have to queue a response to 742 * ep0 within the setup() call, the driver can do it after setup() returns. 743 * The UDC driver must wait until such a response is queued before proceeding 744 * with the data/status stages of the control transfer. 745 * 746 * NOTE: Currently, a number of UDC drivers rely on USB_GADGET_DELAYED_STATUS 747 * being returned from the setup() callback, which is a bug. See the comment 748 * next to USB_GADGET_DELAYED_STATUS for details. 749 * 750 * (Note that only the default control endpoint is supported. Neither 751 * hosts nor devices generally support control traffic except to ep0.) 752 * 753 * Most devices will ignore USB suspend/resume operations, and so will 754 * not provide those callbacks. However, some may need to change modes 755 * when the host is not longer directing those activities. For example, 756 * local controls (buttons, dials, etc) may need to be re-enabled since 757 * the (remote) host can't do that any longer; or an error state might 758 * be cleared, to make the device behave identically whether or not 759 * power is maintained. 760 */ 761 struct usb_gadget_driver { 762 char *function; 763 enum usb_device_speed max_speed; 764 int (*bind)(struct usb_gadget *gadget, 765 struct usb_gadget_driver *driver); 766 void (*unbind)(struct usb_gadget *); 767 int (*setup)(struct usb_gadget *, 768 const struct usb_ctrlrequest *); 769 void (*disconnect)(struct usb_gadget *); 770 void (*suspend)(struct usb_gadget *); 771 void (*resume)(struct usb_gadget *); 772 void (*reset)(struct usb_gadget *); 773 774 /* FIXME support safe rmmod */ 775 struct device_driver driver; 776 777 char *udc_name; 778 unsigned match_existing_only:1; 779 bool is_bound:1; 780 }; 781 782 783 784 /*-------------------------------------------------------------------------*/ 785 786 /* driver modules register and unregister, as usual. 787 * these calls must be made in a context that can sleep. 788 * 789 * A gadget driver can be bound to only one gadget at a time. 790 */ 791 792 /** 793 * usb_gadget_register_driver_owner - register a gadget driver 794 * @driver: the driver being registered 795 * @owner: the driver module 796 * @mod_name: the driver module's build name 797 * Context: can sleep 798 * 799 * Call this in your gadget driver's module initialization function, 800 * to tell the underlying UDC controller driver about your driver. 801 * The @bind() function will be called to bind it to a gadget before this 802 * registration call returns. It's expected that the @bind() function will 803 * be in init sections. 804 * 805 * Use the macro defined below instead of calling this directly. 806 */ 807 int usb_gadget_register_driver_owner(struct usb_gadget_driver *driver, 808 struct module *owner, const char *mod_name); 809 810 /* use a define to avoid include chaining to get THIS_MODULE & friends */ 811 #define usb_gadget_register_driver(driver) \ 812 usb_gadget_register_driver_owner(driver, THIS_MODULE, KBUILD_MODNAME) 813 814 /** 815 * usb_gadget_unregister_driver - unregister a gadget driver 816 * @driver:the driver being unregistered 817 * Context: can sleep 818 * 819 * Call this in your gadget driver's module cleanup function, 820 * to tell the underlying usb controller that your driver is 821 * going away. If the controller is connected to a USB host, 822 * it will first disconnect(). The driver is also requested 823 * to unbind() and clean up any device state, before this procedure 824 * finally returns. It's expected that the unbind() functions 825 * will be in exit sections, so may not be linked in some kernels. 826 */ 827 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver); 828 829 /*-------------------------------------------------------------------------*/ 830 831 /* utility to simplify dealing with string descriptors */ 832 833 /** 834 * struct usb_string - wraps a C string and its USB id 835 * @id:the (nonzero) ID for this string 836 * @s:the string, in UTF-8 encoding 837 * 838 * If you're using usb_gadget_get_string(), use this to wrap a string 839 * together with its ID. 840 */ 841 struct usb_string { 842 u8 id; 843 const char *s; 844 }; 845 846 /** 847 * struct usb_gadget_strings - a set of USB strings in a given language 848 * @language:identifies the strings' language (0x0409 for en-us) 849 * @strings:array of strings with their ids 850 * 851 * If you're using usb_gadget_get_string(), use this to wrap all the 852 * strings for a given language. 853 */ 854 struct usb_gadget_strings { 855 u16 language; /* 0x0409 for en-us */ 856 struct usb_string *strings; 857 }; 858 859 struct usb_gadget_string_container { 860 struct list_head list; 861 u8 *stash[]; 862 }; 863 864 /* put descriptor for string with that id into buf (buflen >= 256) */ 865 int usb_gadget_get_string(const struct usb_gadget_strings *table, int id, u8 *buf); 866 867 /* check if the given language identifier is valid */ 868 bool usb_validate_langid(u16 langid); 869 870 struct gadget_string { 871 struct config_item item; 872 struct list_head list; 873 char string[USB_MAX_STRING_LEN]; 874 struct usb_string usb_string; 875 }; 876 877 #define to_gadget_string(str_item)\ 878 container_of(str_item, struct gadget_string, item) 879 880 /*-------------------------------------------------------------------------*/ 881 882 /* utility to simplify managing config descriptors */ 883 884 /* write vector of descriptors into buffer */ 885 int usb_descriptor_fillbuf(void *, unsigned, 886 const struct usb_descriptor_header **); 887 888 /* copy a NULL-terminated vector of descriptors */ 889 struct usb_descriptor_header **usb_copy_descriptors( 890 struct usb_descriptor_header **); 891 892 /** 893 * usb_free_descriptors - free descriptors returned by usb_copy_descriptors() 894 * @v: vector of descriptors 895 */ 896 static inline void usb_free_descriptors(struct usb_descriptor_header **v) 897 { 898 kfree(v); 899 } 900 901 struct usb_function; 902 int usb_assign_descriptors(struct usb_function *f, 903 struct usb_descriptor_header **fs, 904 struct usb_descriptor_header **hs, 905 struct usb_descriptor_header **ss, 906 struct usb_descriptor_header **ssp); 907 void usb_free_all_descriptors(struct usb_function *f); 908 909 struct usb_descriptor_header *usb_otg_descriptor_alloc( 910 struct usb_gadget *gadget); 911 int usb_otg_descriptor_init(struct usb_gadget *gadget, 912 struct usb_descriptor_header *otg_desc); 913 /*-------------------------------------------------------------------------*/ 914 915 /* utility to simplify map/unmap of usb_requests to/from DMA */ 916 917 #ifdef CONFIG_HAS_DMA 918 extern int usb_gadget_map_request_by_dev(struct device *dev, 919 struct usb_request *req, int is_in); 920 extern int usb_gadget_map_request(struct usb_gadget *gadget, 921 struct usb_request *req, int is_in); 922 923 extern void usb_gadget_unmap_request_by_dev(struct device *dev, 924 struct usb_request *req, int is_in); 925 extern void usb_gadget_unmap_request(struct usb_gadget *gadget, 926 struct usb_request *req, int is_in); 927 #else /* !CONFIG_HAS_DMA */ 928 static inline int usb_gadget_map_request_by_dev(struct device *dev, 929 struct usb_request *req, int is_in) { return -ENOSYS; } 930 static inline int usb_gadget_map_request(struct usb_gadget *gadget, 931 struct usb_request *req, int is_in) { return -ENOSYS; } 932 933 static inline void usb_gadget_unmap_request_by_dev(struct device *dev, 934 struct usb_request *req, int is_in) { } 935 static inline void usb_gadget_unmap_request(struct usb_gadget *gadget, 936 struct usb_request *req, int is_in) { } 937 #endif /* !CONFIG_HAS_DMA */ 938 939 /*-------------------------------------------------------------------------*/ 940 941 /* utility to set gadget state properly */ 942 943 extern void usb_gadget_set_state(struct usb_gadget *gadget, 944 enum usb_device_state state); 945 946 /*-------------------------------------------------------------------------*/ 947 948 /* utility to tell udc core that the bus reset occurs */ 949 extern void usb_gadget_udc_reset(struct usb_gadget *gadget, 950 struct usb_gadget_driver *driver); 951 952 /*-------------------------------------------------------------------------*/ 953 954 /* utility to give requests back to the gadget layer */ 955 956 extern void usb_gadget_giveback_request(struct usb_ep *ep, 957 struct usb_request *req); 958 959 /*-------------------------------------------------------------------------*/ 960 961 /* utility to find endpoint by name */ 962 963 extern struct usb_ep *gadget_find_ep_by_name(struct usb_gadget *g, 964 const char *name); 965 966 /*-------------------------------------------------------------------------*/ 967 968 /* utility to check if endpoint caps match descriptor needs */ 969 970 extern int usb_gadget_ep_match_desc(struct usb_gadget *gadget, 971 struct usb_ep *ep, struct usb_endpoint_descriptor *desc, 972 struct usb_ss_ep_comp_descriptor *ep_comp); 973 974 /*-------------------------------------------------------------------------*/ 975 976 /* utility to update vbus status for udc core, it may be scheduled */ 977 extern void usb_udc_vbus_handler(struct usb_gadget *gadget, bool status); 978 979 /*-------------------------------------------------------------------------*/ 980 981 /* utility wrapping a simple endpoint selection policy */ 982 983 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *, 984 struct usb_endpoint_descriptor *); 985 986 987 extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *, 988 struct usb_endpoint_descriptor *, 989 struct usb_ss_ep_comp_descriptor *); 990 991 extern void usb_ep_autoconfig_release(struct usb_ep *); 992 993 extern void usb_ep_autoconfig_reset(struct usb_gadget *); 994 995 #endif /* __LINUX_USB_GADGET_H */ 996