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