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 * @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 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may 81 * initialize usb_ep.driver data at this time (when it is used). 82 * Note that setting an interface to its current altsetting resets 83 * interface state, and that all interfaces have a disabled state. 84 * @get_alt: Returns the active altsetting. If this is not provided, 85 * then only altsetting zero is supported. 86 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons 87 * include host resetting or reconfiguring the gadget, and disconnection. 88 * @setup: Used for interface-specific control requests. 89 * @suspend: Notifies functions when the host stops sending USB traffic. 90 * @resume: Notifies functions when the host restarts USB traffic. 91 * @get_status: Returns function status as a reply to 92 * GetStatus() request when the recepient is Interface. 93 * @func_suspend: callback to be called when 94 * SetFeature(FUNCTION_SUSPEND) is reseived 95 * 96 * A single USB function uses one or more interfaces, and should in most 97 * cases support operation at both full and high speeds. Each function is 98 * associated by @usb_add_function() with a one configuration; that function 99 * causes @bind() to be called so resources can be allocated as part of 100 * setting up a gadget driver. Those resources include endpoints, which 101 * should be allocated using @usb_ep_autoconfig(). 102 * 103 * To support dual speed operation, a function driver provides descriptors 104 * for both high and full speed operation. Except in rare cases that don't 105 * involve bulk endpoints, each speed needs different endpoint descriptors. 106 * 107 * Function drivers choose their own strategies for managing instance data. 108 * The simplest strategy just declares it "static', which means the function 109 * can only be activated once. If the function needs to be exposed in more 110 * than one configuration at a given speed, it needs to support multiple 111 * usb_function structures (one for each configuration). 112 * 113 * A more complex strategy might encapsulate a @usb_function structure inside 114 * a driver-specific instance structure to allows multiple activations. An 115 * example of multiple activations might be a CDC ACM function that supports 116 * two or more distinct instances within the same configuration, providing 117 * several independent logical data links to a USB host. 118 */ 119 struct usb_function { 120 const char *name; 121 struct usb_gadget_strings **strings; 122 struct usb_descriptor_header **fs_descriptors; 123 struct usb_descriptor_header **hs_descriptors; 124 struct usb_descriptor_header **ss_descriptors; 125 126 struct usb_configuration *config; 127 128 /* REVISIT: bind() functions can be marked __init, which 129 * makes trouble for section mismatch analysis. See if 130 * we can't restructure things to avoid mismatching. 131 * Related: unbind() may kfree() but bind() won't... 132 */ 133 134 /* configuration management: bind/unbind */ 135 int (*bind)(struct usb_configuration *, 136 struct usb_function *); 137 void (*unbind)(struct usb_configuration *, 138 struct usb_function *); 139 140 /* runtime state management */ 141 int (*set_alt)(struct usb_function *, 142 unsigned interface, unsigned alt); 143 int (*get_alt)(struct usb_function *, 144 unsigned interface); 145 void (*disable)(struct usb_function *); 146 int (*setup)(struct usb_function *, 147 const struct usb_ctrlrequest *); 148 void (*suspend)(struct usb_function *); 149 void (*resume)(struct usb_function *); 150 151 /* USB 3.0 additions */ 152 int (*get_status)(struct usb_function *); 153 int (*func_suspend)(struct usb_function *, 154 u8 suspend_opt); 155 /* private: */ 156 /* internals */ 157 struct list_head list; 158 DECLARE_BITMAP(endpoints, 32); 159 }; 160 161 int usb_add_function(struct usb_configuration *, struct usb_function *); 162 163 int usb_function_deactivate(struct usb_function *); 164 int usb_function_activate(struct usb_function *); 165 166 int usb_interface_id(struct usb_configuration *, struct usb_function *); 167 168 int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, 169 struct usb_ep *_ep); 170 171 #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */ 172 173 /** 174 * struct usb_configuration - represents one gadget configuration 175 * @label: For diagnostics, describes the configuration. 176 * @strings: Tables of strings, keyed by identifiers assigned during @bind() 177 * and by language IDs provided in control requests. 178 * @descriptors: Table of descriptors preceding all function descriptors. 179 * Examples include OTG and vendor-specific descriptors. 180 * @unbind: Reverses @bind; called as a side effect of unregistering the 181 * driver which added this configuration. 182 * @setup: Used to delegate control requests that aren't handled by standard 183 * device infrastructure or directed at a specific interface. 184 * @bConfigurationValue: Copied into configuration descriptor. 185 * @iConfiguration: Copied into configuration descriptor. 186 * @bmAttributes: Copied into configuration descriptor. 187 * @bMaxPower: Copied into configuration descriptor. 188 * @cdev: assigned by @usb_add_config() before calling @bind(); this is 189 * the device associated with this configuration. 190 * 191 * Configurations are building blocks for gadget drivers structured around 192 * function drivers. Simple USB gadgets require only one function and one 193 * configuration, and handle dual-speed hardware by always providing the same 194 * functionality. Slightly more complex gadgets may have more than one 195 * single-function configuration at a given speed; or have configurations 196 * that only work at one speed. 197 * 198 * Composite devices are, by definition, ones with configurations which 199 * include more than one function. 200 * 201 * The lifecycle of a usb_configuration includes allocation, initialization 202 * of the fields described above, and calling @usb_add_config() to set up 203 * internal data and bind it to a specific device. The configuration's 204 * @bind() method is then used to initialize all the functions and then 205 * call @usb_add_function() for them. 206 * 207 * Those functions would normally be independent of each other, but that's 208 * not mandatory. CDC WMC devices are an example where functions often 209 * depend on other functions, with some functions subsidiary to others. 210 * Such interdependency may be managed in any way, so long as all of the 211 * descriptors complete by the time the composite driver returns from 212 * its bind() routine. 213 */ 214 struct usb_configuration { 215 const char *label; 216 struct usb_gadget_strings **strings; 217 const struct usb_descriptor_header **descriptors; 218 219 /* REVISIT: bind() functions can be marked __init, which 220 * makes trouble for section mismatch analysis. See if 221 * we can't restructure things to avoid mismatching... 222 */ 223 224 /* configuration management: unbind/setup */ 225 void (*unbind)(struct usb_configuration *); 226 int (*setup)(struct usb_configuration *, 227 const struct usb_ctrlrequest *); 228 229 /* fields in the config descriptor */ 230 u8 bConfigurationValue; 231 u8 iConfiguration; 232 u8 bmAttributes; 233 u8 bMaxPower; 234 235 struct usb_composite_dev *cdev; 236 237 /* private: */ 238 /* internals */ 239 struct list_head list; 240 struct list_head functions; 241 u8 next_interface_id; 242 unsigned superspeed:1; 243 unsigned highspeed:1; 244 unsigned fullspeed:1; 245 struct usb_function *interface[MAX_CONFIG_INTERFACES]; 246 }; 247 248 int usb_add_config(struct usb_composite_dev *, 249 struct usb_configuration *, 250 int (*)(struct usb_configuration *)); 251 252 void usb_remove_config(struct usb_composite_dev *, 253 struct usb_configuration *); 254 255 /* predefined index for usb_composite_driver */ 256 enum { 257 USB_GADGET_MANUFACTURER_IDX = 0, 258 USB_GADGET_PRODUCT_IDX, 259 USB_GADGET_SERIAL_IDX, 260 USB_GADGET_FIRST_AVAIL_IDX, 261 }; 262 263 /** 264 * struct usb_composite_driver - groups configurations into a gadget 265 * @name: For diagnostics, identifies the driver. 266 * @dev: Template descriptor for the device, including default device 267 * identifiers. 268 * @strings: tables of strings, keyed by identifiers assigned during @bind 269 * and language IDs provided in control requests. Note: The first entries 270 * are predefined. The first entry that may be used is 271 * USB_GADGET_FIRST_AVAIL_IDX 272 * @max_speed: Highest speed the driver supports. 273 * @needs_serial: set to 1 if the gadget needs userspace to provide 274 * a serial number. If one is not provided, warning will be printed. 275 * @bind: (REQUIRED) Used to allocate resources that are shared across the 276 * whole device, such as string IDs, and add its configurations using 277 * @usb_add_config(). This may fail by returning a negative errno 278 * value; it should return zero on successful initialization. 279 * @unbind: Reverses @bind; called as a side effect of unregistering 280 * this driver. 281 * @disconnect: optional driver disconnect method 282 * @suspend: Notifies when the host stops sending USB traffic, 283 * after function notifications 284 * @resume: Notifies configuration when the host restarts USB traffic, 285 * before function notifications 286 * 287 * Devices default to reporting self powered operation. Devices which rely 288 * on bus powered operation should report this in their @bind method. 289 * 290 * Before returning from @bind, various fields in the template descriptor 291 * may be overridden. These include the idVendor/idProduct/bcdDevice values 292 * normally to bind the appropriate host side driver, and the three strings 293 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user 294 * meaningful device identifiers. (The strings will not be defined unless 295 * they are defined in @dev and @strings.) The correct ep0 maxpacket size 296 * is also reported, as defined by the underlying controller driver. 297 */ 298 struct usb_composite_driver { 299 const char *name; 300 const struct usb_device_descriptor *dev; 301 struct usb_gadget_strings **strings; 302 enum usb_device_speed max_speed; 303 unsigned needs_serial:1; 304 305 int (*bind)(struct usb_composite_dev *cdev); 306 int (*unbind)(struct usb_composite_dev *); 307 308 void (*disconnect)(struct usb_composite_dev *); 309 310 /* global suspend hooks */ 311 void (*suspend)(struct usb_composite_dev *); 312 void (*resume)(struct usb_composite_dev *); 313 struct usb_gadget_driver gadget_driver; 314 }; 315 316 extern int usb_composite_probe(struct usb_composite_driver *driver); 317 extern void usb_composite_unregister(struct usb_composite_driver *driver); 318 extern void usb_composite_setup_continue(struct usb_composite_dev *cdev); 319 320 321 /** 322 * struct usb_composite_device - represents one composite usb gadget 323 * @gadget: read-only, abstracts the gadget's usb peripheral controller 324 * @req: used for control responses; buffer is pre-allocated 325 * @config: the currently active configuration 326 * 327 * One of these devices is allocated and initialized before the 328 * associated device driver's bind() is called. 329 * 330 * OPEN ISSUE: it appears that some WUSB devices will need to be 331 * built by combining a normal (wired) gadget with a wireless one. 332 * This revision of the gadget framework should probably try to make 333 * sure doing that won't hurt too much. 334 * 335 * One notion for how to handle Wireless USB devices involves: 336 * (a) a second gadget here, discovery mechanism TBD, but likely 337 * needing separate "register/unregister WUSB gadget" calls; 338 * (b) updates to usb_gadget to include flags "is it wireless", 339 * "is it wired", plus (presumably in a wrapper structure) 340 * bandgroup and PHY info; 341 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting 342 * wireless-specific parameters like maxburst and maxsequence; 343 * (d) configurations that are specific to wireless links; 344 * (e) function drivers that understand wireless configs and will 345 * support wireless for (additional) function instances; 346 * (f) a function to support association setup (like CBAF), not 347 * necessarily requiring a wireless adapter; 348 * (g) composite device setup that can create one or more wireless 349 * configs, including appropriate association setup support; 350 * (h) more, TBD. 351 */ 352 struct usb_composite_dev { 353 struct usb_gadget *gadget; 354 struct usb_request *req; 355 356 struct usb_configuration *config; 357 358 /* private: */ 359 /* internals */ 360 unsigned int suspended:1; 361 struct usb_device_descriptor desc; 362 struct list_head configs; 363 struct usb_composite_driver *driver; 364 u8 next_string_id; 365 char *def_manufacturer; 366 367 /* the gadget driver won't enable the data pullup 368 * while the deactivation count is nonzero. 369 */ 370 unsigned deactivations; 371 372 /* the composite driver won't complete the control transfer's 373 * data/status stages till delayed_status is zero. 374 */ 375 int delayed_status; 376 377 /* protects deactivations and delayed_status counts*/ 378 spinlock_t lock; 379 }; 380 381 extern int usb_string_id(struct usb_composite_dev *c); 382 extern int usb_string_ids_tab(struct usb_composite_dev *c, 383 struct usb_string *str); 384 extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n); 385 386 /* 387 * Some systems will need runtime overrides for the product identifiers 388 * published in the device descriptor, either numbers or strings or both. 389 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters). 390 */ 391 struct usb_composite_overwrite { 392 u16 idVendor; 393 u16 idProduct; 394 u16 bcdDevice; 395 char *serial_number; 396 char *manufacturer; 397 char *product; 398 }; 399 #define USB_GADGET_COMPOSITE_OPTIONS() \ 400 static struct usb_composite_overwrite coverwrite; \ 401 \ 402 module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \ 403 MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \ 404 \ 405 module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \ 406 MODULE_PARM_DESC(idProduct, "USB Product ID"); \ 407 \ 408 module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \ 409 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \ 410 \ 411 module_param_named(iSerialNumber, coverwrite.serial_number, charp, \ 412 S_IRUGO); \ 413 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \ 414 \ 415 module_param_named(iManufacturer, coverwrite.manufacturer, charp, \ 416 S_IRUGO); \ 417 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \ 418 \ 419 module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \ 420 MODULE_PARM_DESC(iProduct, "USB Product string") 421 422 void usb_composite_overwrite_options(struct usb_composite_dev *cdev, 423 struct usb_composite_overwrite *covr); 424 425 static inline u16 get_default_bcdDevice(void) 426 { 427 u16 bcdDevice; 428 429 bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8; 430 bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff)); 431 return bcdDevice; 432 } 433 434 /* messaging utils */ 435 #define DBG(d, fmt, args...) \ 436 dev_dbg(&(d)->gadget->dev , fmt , ## args) 437 #define VDBG(d, fmt, args...) \ 438 dev_vdbg(&(d)->gadget->dev , fmt , ## args) 439 #define ERROR(d, fmt, args...) \ 440 dev_err(&(d)->gadget->dev , fmt , ## args) 441 #define WARNING(d, fmt, args...) \ 442 dev_warn(&(d)->gadget->dev , fmt , ## args) 443 #define INFO(d, fmt, args...) \ 444 dev_info(&(d)->gadget->dev , fmt , ## args) 445 446 #endif /* __LINUX_USB_COMPOSITE_H */ 447