1 /* 2 * composite.h -- framework for usb gadgets which are composite devices 3 * 4 * Copyright (C) 2006-2008 David Brownell 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #ifndef __LINUX_USB_COMPOSITE_H 22 #define __LINUX_USB_COMPOSITE_H 23 24 /* 25 * This framework is an optional layer on top of the USB Gadget interface, 26 * making it easier to build (a) Composite devices, supporting multiple 27 * functions within any single configuration, and (b) Multi-configuration 28 * devices, also supporting multiple functions but without necessarily 29 * having more than one function per configuration. 30 * 31 * Example: a device with a single configuration supporting both network 32 * link and mass storage functions is a composite device. Those functions 33 * might alternatively be packaged in individual configurations, but in 34 * the composite model the host can use both functions at the same time. 35 */ 36 37 #include <linux/bcd.h> 38 #include <linux/version.h> 39 #include <linux/usb/ch9.h> 40 #include <linux/usb/gadget.h> 41 #include <linux/log2.h> 42 43 /* 44 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they 45 * wish to delay the data/status stages of the control transfer till they 46 * are ready. The control transfer will then be kept from completing till 47 * all the function drivers that requested for USB_GADGET_DELAYED_STAUS 48 * invoke usb_composite_setup_continue(). 49 */ 50 #define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */ 51 52 /* big enough to hold our biggest descriptor */ 53 #define USB_COMP_EP0_BUFSIZ 1024 54 55 #define USB_MS_TO_HS_INTERVAL(x) (ilog2((x * 1000 / 125)) + 1) 56 struct usb_configuration; 57 58 /** 59 * struct usb_function - describes one function of a configuration 60 * @name: For diagnostics, identifies the function. 61 * @strings: tables of strings, keyed by identifiers assigned during bind() 62 * and by language IDs provided in control requests 63 * @fs_descriptors: Table of full (or low) speed descriptors, using interface and 64 * string identifiers assigned during @bind(). If this pointer is null, 65 * the function will not be available at full speed (or at low speed). 66 * @hs_descriptors: Table of high speed descriptors, using interface and 67 * string identifiers assigned during @bind(). If this pointer is null, 68 * the function will not be available at high speed. 69 * @ss_descriptors: Table of super speed descriptors, using interface and 70 * string identifiers assigned during @bind(). If this 71 * pointer is null after initiation, the function will not 72 * be available at super speed. 73 * @config: assigned when @usb_add_function() is called; this is the 74 * configuration with which this function is associated. 75 * @bind: Before the gadget can register, all of its functions bind() to the 76 * available resources including string and interface identifiers used 77 * in interface or class descriptors; endpoints; I/O buffers; and so on. 78 * @unbind: Reverses @bind; called as a side effect of unregistering the 79 * driver which added this function. 80 * @free_func: free the struct usb_function. 81 * @mod: (internal) points to the module that created this structure. 82 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may 83 * initialize usb_ep.driver data at this time (when it is used). 84 * Note that setting an interface to its current altsetting resets 85 * interface state, and that all interfaces have a disabled state. 86 * @get_alt: Returns the active altsetting. If this is not provided, 87 * then only altsetting zero is supported. 88 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons 89 * include host resetting or reconfiguring the gadget, and disconnection. 90 * @setup: Used for interface-specific control requests. 91 * @suspend: Notifies functions when the host stops sending USB traffic. 92 * @resume: Notifies functions when the host restarts USB traffic. 93 * @get_status: Returns function status as a reply to 94 * GetStatus() request when the recepient is Interface. 95 * @func_suspend: callback to be called when 96 * SetFeature(FUNCTION_SUSPEND) is reseived 97 * 98 * A single USB function uses one or more interfaces, and should in most 99 * cases support operation at both full and high speeds. Each function is 100 * associated by @usb_add_function() with a one configuration; that function 101 * causes @bind() to be called so resources can be allocated as part of 102 * setting up a gadget driver. Those resources include endpoints, which 103 * should be allocated using @usb_ep_autoconfig(). 104 * 105 * To support dual speed operation, a function driver provides descriptors 106 * for both high and full speed operation. Except in rare cases that don't 107 * involve bulk endpoints, each speed needs different endpoint descriptors. 108 * 109 * Function drivers choose their own strategies for managing instance data. 110 * The simplest strategy just declares it "static', which means the function 111 * can only be activated once. If the function needs to be exposed in more 112 * than one configuration at a given speed, it needs to support multiple 113 * usb_function structures (one for each configuration). 114 * 115 * A more complex strategy might encapsulate a @usb_function structure inside 116 * a driver-specific instance structure to allows multiple activations. An 117 * example of multiple activations might be a CDC ACM function that supports 118 * two or more distinct instances within the same configuration, providing 119 * several independent logical data links to a USB host. 120 */ 121 122 struct usb_function { 123 const char *name; 124 struct usb_gadget_strings **strings; 125 struct usb_descriptor_header **fs_descriptors; 126 struct usb_descriptor_header **hs_descriptors; 127 struct usb_descriptor_header **ss_descriptors; 128 129 struct usb_configuration *config; 130 131 /* REVISIT: bind() functions can be marked __init, which 132 * makes trouble for section mismatch analysis. See if 133 * we can't restructure things to avoid mismatching. 134 * Related: unbind() may kfree() but bind() won't... 135 */ 136 137 /* configuration management: bind/unbind */ 138 int (*bind)(struct usb_configuration *, 139 struct usb_function *); 140 void (*unbind)(struct usb_configuration *, 141 struct usb_function *); 142 void (*free_func)(struct usb_function *f); 143 struct module *mod; 144 145 /* runtime state management */ 146 int (*set_alt)(struct usb_function *, 147 unsigned interface, unsigned alt); 148 int (*get_alt)(struct usb_function *, 149 unsigned interface); 150 void (*disable)(struct usb_function *); 151 int (*setup)(struct usb_function *, 152 const struct usb_ctrlrequest *); 153 void (*suspend)(struct usb_function *); 154 void (*resume)(struct usb_function *); 155 156 /* USB 3.0 additions */ 157 int (*get_status)(struct usb_function *); 158 int (*func_suspend)(struct usb_function *, 159 u8 suspend_opt); 160 /* private: */ 161 /* internals */ 162 struct list_head list; 163 DECLARE_BITMAP(endpoints, 32); 164 const struct usb_function_instance *fi; 165 }; 166 167 int usb_add_function(struct usb_configuration *, struct usb_function *); 168 169 int usb_function_deactivate(struct usb_function *); 170 int usb_function_activate(struct usb_function *); 171 172 int usb_interface_id(struct usb_configuration *, struct usb_function *); 173 174 int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, 175 struct usb_ep *_ep); 176 177 #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */ 178 179 /** 180 * struct usb_configuration - represents one gadget configuration 181 * @label: For diagnostics, describes the configuration. 182 * @strings: Tables of strings, keyed by identifiers assigned during @bind() 183 * and by language IDs provided in control requests. 184 * @descriptors: Table of descriptors preceding all function descriptors. 185 * Examples include OTG and vendor-specific descriptors. 186 * @unbind: Reverses @bind; called as a side effect of unregistering the 187 * driver which added this configuration. 188 * @setup: Used to delegate control requests that aren't handled by standard 189 * device infrastructure or directed at a specific interface. 190 * @bConfigurationValue: Copied into configuration descriptor. 191 * @iConfiguration: Copied into configuration descriptor. 192 * @bmAttributes: Copied into configuration descriptor. 193 * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the 194 * configuration descriptor after considering the bus speed. 195 * @cdev: assigned by @usb_add_config() before calling @bind(); this is 196 * the device associated with this configuration. 197 * 198 * Configurations are building blocks for gadget drivers structured around 199 * function drivers. Simple USB gadgets require only one function and one 200 * configuration, and handle dual-speed hardware by always providing the same 201 * functionality. Slightly more complex gadgets may have more than one 202 * single-function configuration at a given speed; or have configurations 203 * that only work at one speed. 204 * 205 * Composite devices are, by definition, ones with configurations which 206 * include more than one function. 207 * 208 * The lifecycle of a usb_configuration includes allocation, initialization 209 * of the fields described above, and calling @usb_add_config() to set up 210 * internal data and bind it to a specific device. The configuration's 211 * @bind() method is then used to initialize all the functions and then 212 * call @usb_add_function() for them. 213 * 214 * Those functions would normally be independent of each other, but that's 215 * not mandatory. CDC WMC devices are an example where functions often 216 * depend on other functions, with some functions subsidiary to others. 217 * Such interdependency may be managed in any way, so long as all of the 218 * descriptors complete by the time the composite driver returns from 219 * its bind() routine. 220 */ 221 struct usb_configuration { 222 const char *label; 223 struct usb_gadget_strings **strings; 224 const struct usb_descriptor_header **descriptors; 225 226 /* REVISIT: bind() functions can be marked __init, which 227 * makes trouble for section mismatch analysis. See if 228 * we can't restructure things to avoid mismatching... 229 */ 230 231 /* configuration management: unbind/setup */ 232 void (*unbind)(struct usb_configuration *); 233 int (*setup)(struct usb_configuration *, 234 const struct usb_ctrlrequest *); 235 236 /* fields in the config descriptor */ 237 u8 bConfigurationValue; 238 u8 iConfiguration; 239 u8 bmAttributes; 240 u16 MaxPower; 241 242 struct usb_composite_dev *cdev; 243 244 /* private: */ 245 /* internals */ 246 struct list_head list; 247 struct list_head functions; 248 u8 next_interface_id; 249 unsigned superspeed:1; 250 unsigned highspeed:1; 251 unsigned fullspeed:1; 252 struct usb_function *interface[MAX_CONFIG_INTERFACES]; 253 }; 254 255 int usb_add_config(struct usb_composite_dev *, 256 struct usb_configuration *, 257 int (*)(struct usb_configuration *)); 258 259 void usb_remove_config(struct usb_composite_dev *, 260 struct usb_configuration *); 261 262 /* predefined index for usb_composite_driver */ 263 enum { 264 USB_GADGET_MANUFACTURER_IDX = 0, 265 USB_GADGET_PRODUCT_IDX, 266 USB_GADGET_SERIAL_IDX, 267 USB_GADGET_FIRST_AVAIL_IDX, 268 }; 269 270 /** 271 * struct usb_composite_driver - groups configurations into a gadget 272 * @name: For diagnostics, identifies the driver. 273 * @dev: Template descriptor for the device, including default device 274 * identifiers. 275 * @strings: tables of strings, keyed by identifiers assigned during @bind 276 * and language IDs provided in control requests. Note: The first entries 277 * are predefined. The first entry that may be used is 278 * USB_GADGET_FIRST_AVAIL_IDX 279 * @max_speed: Highest speed the driver supports. 280 * @needs_serial: set to 1 if the gadget needs userspace to provide 281 * a serial number. If one is not provided, warning will be printed. 282 * @bind: (REQUIRED) Used to allocate resources that are shared across the 283 * whole device, such as string IDs, and add its configurations using 284 * @usb_add_config(). This may fail by returning a negative errno 285 * value; it should return zero on successful initialization. 286 * @unbind: Reverses @bind; called as a side effect of unregistering 287 * this driver. 288 * @disconnect: optional driver disconnect method 289 * @suspend: Notifies when the host stops sending USB traffic, 290 * after function notifications 291 * @resume: Notifies configuration when the host restarts USB traffic, 292 * before function notifications 293 * @gadget_driver: Gadget driver controlling this driver 294 * 295 * Devices default to reporting self powered operation. Devices which rely 296 * on bus powered operation should report this in their @bind method. 297 * 298 * Before returning from @bind, various fields in the template descriptor 299 * may be overridden. These include the idVendor/idProduct/bcdDevice values 300 * normally to bind the appropriate host side driver, and the three strings 301 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user 302 * meaningful device identifiers. (The strings will not be defined unless 303 * they are defined in @dev and @strings.) The correct ep0 maxpacket size 304 * is also reported, as defined by the underlying controller driver. 305 */ 306 struct usb_composite_driver { 307 const char *name; 308 const struct usb_device_descriptor *dev; 309 struct usb_gadget_strings **strings; 310 enum usb_device_speed max_speed; 311 unsigned needs_serial:1; 312 313 int (*bind)(struct usb_composite_dev *cdev); 314 int (*unbind)(struct usb_composite_dev *); 315 316 void (*disconnect)(struct usb_composite_dev *); 317 318 /* global suspend hooks */ 319 void (*suspend)(struct usb_composite_dev *); 320 void (*resume)(struct usb_composite_dev *); 321 struct usb_gadget_driver gadget_driver; 322 }; 323 324 extern int usb_composite_probe(struct usb_composite_driver *driver); 325 extern void usb_composite_unregister(struct usb_composite_driver *driver); 326 extern void usb_composite_setup_continue(struct usb_composite_dev *cdev); 327 extern int composite_dev_prepare(struct usb_composite_driver *composite, 328 struct usb_composite_dev *cdev); 329 void composite_dev_cleanup(struct usb_composite_dev *cdev); 330 331 static inline struct usb_composite_driver *to_cdriver( 332 struct usb_gadget_driver *gdrv) 333 { 334 return container_of(gdrv, struct usb_composite_driver, gadget_driver); 335 } 336 337 /** 338 * struct usb_composite_device - represents one composite usb gadget 339 * @gadget: read-only, abstracts the gadget's usb peripheral controller 340 * @req: used for control responses; buffer is pre-allocated 341 * @config: the currently active configuration 342 * 343 * One of these devices is allocated and initialized before the 344 * associated device driver's bind() is called. 345 * 346 * OPEN ISSUE: it appears that some WUSB devices will need to be 347 * built by combining a normal (wired) gadget with a wireless one. 348 * This revision of the gadget framework should probably try to make 349 * sure doing that won't hurt too much. 350 * 351 * One notion for how to handle Wireless USB devices involves: 352 * (a) a second gadget here, discovery mechanism TBD, but likely 353 * needing separate "register/unregister WUSB gadget" calls; 354 * (b) updates to usb_gadget to include flags "is it wireless", 355 * "is it wired", plus (presumably in a wrapper structure) 356 * bandgroup and PHY info; 357 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting 358 * wireless-specific parameters like maxburst and maxsequence; 359 * (d) configurations that are specific to wireless links; 360 * (e) function drivers that understand wireless configs and will 361 * support wireless for (additional) function instances; 362 * (f) a function to support association setup (like CBAF), not 363 * necessarily requiring a wireless adapter; 364 * (g) composite device setup that can create one or more wireless 365 * configs, including appropriate association setup support; 366 * (h) more, TBD. 367 */ 368 struct usb_composite_dev { 369 struct usb_gadget *gadget; 370 struct usb_request *req; 371 372 struct usb_configuration *config; 373 374 /* private: */ 375 /* internals */ 376 unsigned int suspended:1; 377 struct usb_device_descriptor desc; 378 struct list_head configs; 379 struct list_head gstrings; 380 struct usb_composite_driver *driver; 381 u8 next_string_id; 382 char *def_manufacturer; 383 384 /* the gadget driver won't enable the data pullup 385 * while the deactivation count is nonzero. 386 */ 387 unsigned deactivations; 388 389 /* the composite driver won't complete the control transfer's 390 * data/status stages till delayed_status is zero. 391 */ 392 int delayed_status; 393 394 /* protects deactivations and delayed_status counts*/ 395 spinlock_t lock; 396 }; 397 398 extern int usb_string_id(struct usb_composite_dev *c); 399 extern int usb_string_ids_tab(struct usb_composite_dev *c, 400 struct usb_string *str); 401 extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev, 402 struct usb_gadget_strings **sp, unsigned n_strings); 403 404 extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n); 405 406 extern void composite_disconnect(struct usb_gadget *gadget); 407 extern int composite_setup(struct usb_gadget *gadget, 408 const struct usb_ctrlrequest *ctrl); 409 410 /* 411 * Some systems will need runtime overrides for the product identifiers 412 * published in the device descriptor, either numbers or strings or both. 413 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters). 414 */ 415 struct usb_composite_overwrite { 416 u16 idVendor; 417 u16 idProduct; 418 u16 bcdDevice; 419 char *serial_number; 420 char *manufacturer; 421 char *product; 422 }; 423 #define USB_GADGET_COMPOSITE_OPTIONS() \ 424 static struct usb_composite_overwrite coverwrite; \ 425 \ 426 module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \ 427 MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \ 428 \ 429 module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \ 430 MODULE_PARM_DESC(idProduct, "USB Product ID"); \ 431 \ 432 module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \ 433 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \ 434 \ 435 module_param_named(iSerialNumber, coverwrite.serial_number, charp, \ 436 S_IRUGO); \ 437 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \ 438 \ 439 module_param_named(iManufacturer, coverwrite.manufacturer, charp, \ 440 S_IRUGO); \ 441 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \ 442 \ 443 module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \ 444 MODULE_PARM_DESC(iProduct, "USB Product string") 445 446 void usb_composite_overwrite_options(struct usb_composite_dev *cdev, 447 struct usb_composite_overwrite *covr); 448 449 static inline u16 get_default_bcdDevice(void) 450 { 451 u16 bcdDevice; 452 453 bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8; 454 bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff)); 455 return bcdDevice; 456 } 457 458 struct usb_function_driver { 459 const char *name; 460 struct module *mod; 461 struct list_head list; 462 struct usb_function_instance *(*alloc_inst)(void); 463 struct usb_function *(*alloc_func)(struct usb_function_instance *inst); 464 }; 465 466 struct usb_function_instance { 467 struct usb_function_driver *fd; 468 void (*free_func_inst)(struct usb_function_instance *inst); 469 }; 470 471 void usb_function_unregister(struct usb_function_driver *f); 472 int usb_function_register(struct usb_function_driver *newf); 473 void usb_put_function_instance(struct usb_function_instance *fi); 474 void usb_put_function(struct usb_function *f); 475 struct usb_function_instance *usb_get_function_instance(const char *name); 476 struct usb_function *usb_get_function(struct usb_function_instance *fi); 477 478 struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev, 479 int val); 480 int usb_add_config_only(struct usb_composite_dev *cdev, 481 struct usb_configuration *config); 482 void usb_remove_function(struct usb_configuration *c, struct usb_function *f); 483 484 #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \ 485 static struct usb_function_driver _name ## usb_func = { \ 486 .name = __stringify(_name), \ 487 .mod = THIS_MODULE, \ 488 .alloc_inst = _inst_alloc, \ 489 .alloc_func = _func_alloc, \ 490 }; \ 491 MODULE_ALIAS("usbfunc:"__stringify(_name)); 492 493 #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc) \ 494 DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \ 495 static int __init _name ## mod_init(void) \ 496 { \ 497 return usb_function_register(&_name ## usb_func); \ 498 } \ 499 static void __exit _name ## mod_exit(void) \ 500 { \ 501 usb_function_unregister(&_name ## usb_func); \ 502 } \ 503 module_init(_name ## mod_init); \ 504 module_exit(_name ## mod_exit) 505 506 /* messaging utils */ 507 #define DBG(d, fmt, args...) \ 508 dev_dbg(&(d)->gadget->dev , fmt , ## args) 509 #define VDBG(d, fmt, args...) \ 510 dev_vdbg(&(d)->gadget->dev , fmt , ## args) 511 #define ERROR(d, fmt, args...) \ 512 dev_err(&(d)->gadget->dev , fmt , ## args) 513 #define WARNING(d, fmt, args...) \ 514 dev_warn(&(d)->gadget->dev , fmt , ## args) 515 #define INFO(d, fmt, args...) \ 516 dev_info(&(d)->gadget->dev , fmt , ## args) 517 518 #endif /* __LINUX_USB_COMPOSITE_H */ 519