1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Provides code common for host and device side USB. 4 * 5 * If either host side (ie. CONFIG_USB=y) or device side USB stack 6 * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is 7 * compiled-in as well. Otherwise, if either of the two stacks is 8 * compiled as module, this file is compiled as module as well. 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/platform_device.h> 15 #include <linux/usb/ch9.h> 16 #include <linux/usb/of.h> 17 #include <linux/usb/otg.h> 18 #include <linux/of_platform.h> 19 #include <linux/debugfs.h> 20 #include "common.h" 21 22 static const char *const ep_type_names[] = { 23 [USB_ENDPOINT_XFER_CONTROL] = "ctrl", 24 [USB_ENDPOINT_XFER_ISOC] = "isoc", 25 [USB_ENDPOINT_XFER_BULK] = "bulk", 26 [USB_ENDPOINT_XFER_INT] = "intr", 27 }; 28 29 /** 30 * usb_ep_type_string() - Returns human readable-name of the endpoint type. 31 * @ep_type: The endpoint type to return human-readable name for. If it's not 32 * any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT}, 33 * usually got by usb_endpoint_type(), the string 'unknown' will be returned. 34 */ 35 const char *usb_ep_type_string(int ep_type) 36 { 37 if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names)) 38 return "unknown"; 39 40 return ep_type_names[ep_type]; 41 } 42 EXPORT_SYMBOL_GPL(usb_ep_type_string); 43 44 const char *usb_otg_state_string(enum usb_otg_state state) 45 { 46 static const char *const names[] = { 47 [OTG_STATE_A_IDLE] = "a_idle", 48 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise", 49 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon", 50 [OTG_STATE_A_HOST] = "a_host", 51 [OTG_STATE_A_SUSPEND] = "a_suspend", 52 [OTG_STATE_A_PERIPHERAL] = "a_peripheral", 53 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall", 54 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err", 55 [OTG_STATE_B_IDLE] = "b_idle", 56 [OTG_STATE_B_SRP_INIT] = "b_srp_init", 57 [OTG_STATE_B_PERIPHERAL] = "b_peripheral", 58 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon", 59 [OTG_STATE_B_HOST] = "b_host", 60 }; 61 62 if (state < 0 || state >= ARRAY_SIZE(names)) 63 return "UNDEFINED"; 64 65 return names[state]; 66 } 67 EXPORT_SYMBOL_GPL(usb_otg_state_string); 68 69 static const char *const speed_names[] = { 70 [USB_SPEED_UNKNOWN] = "UNKNOWN", 71 [USB_SPEED_LOW] = "low-speed", 72 [USB_SPEED_FULL] = "full-speed", 73 [USB_SPEED_HIGH] = "high-speed", 74 [USB_SPEED_WIRELESS] = "wireless", 75 [USB_SPEED_SUPER] = "super-speed", 76 [USB_SPEED_SUPER_PLUS] = "super-speed-plus", 77 }; 78 79 static const char *const ssp_rate[] = { 80 [USB_SSP_GEN_UNKNOWN] = "UNKNOWN", 81 [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1", 82 [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2", 83 [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2", 84 }; 85 86 /** 87 * usb_speed_string() - Returns human readable-name of the speed. 88 * @speed: The speed to return human-readable name for. If it's not 89 * any of the speeds defined in usb_device_speed enum, string for 90 * USB_SPEED_UNKNOWN will be returned. 91 */ 92 const char *usb_speed_string(enum usb_device_speed speed) 93 { 94 if (speed < 0 || speed >= ARRAY_SIZE(speed_names)) 95 speed = USB_SPEED_UNKNOWN; 96 return speed_names[speed]; 97 } 98 EXPORT_SYMBOL_GPL(usb_speed_string); 99 100 /** 101 * usb_get_maximum_speed - Get maximum requested speed for a given USB 102 * controller. 103 * @dev: Pointer to the given USB controller device 104 * 105 * The function gets the maximum speed string from property "maximum-speed", 106 * and returns the corresponding enum usb_device_speed. 107 */ 108 enum usb_device_speed usb_get_maximum_speed(struct device *dev) 109 { 110 const char *maximum_speed; 111 int ret; 112 113 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed); 114 if (ret < 0) 115 return USB_SPEED_UNKNOWN; 116 117 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed); 118 if (ret > 0) 119 return USB_SPEED_SUPER_PLUS; 120 121 ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed); 122 return (ret < 0) ? USB_SPEED_UNKNOWN : ret; 123 } 124 EXPORT_SYMBOL_GPL(usb_get_maximum_speed); 125 126 /** 127 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count 128 * of a SuperSpeed Plus capable device. 129 * @dev: Pointer to the given USB controller device 130 * 131 * If the string from "maximum-speed" property is super-speed-plus-genXxY where 132 * 'X' is the generation number and 'Y' is the number of lanes, then this 133 * function returns the corresponding enum usb_ssp_rate. 134 */ 135 enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev) 136 { 137 const char *maximum_speed; 138 int ret; 139 140 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed); 141 if (ret < 0) 142 return USB_SSP_GEN_UNKNOWN; 143 144 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed); 145 return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret; 146 } 147 EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate); 148 149 /** 150 * usb_state_string - Returns human readable name for the state. 151 * @state: The state to return a human-readable name for. If it's not 152 * any of the states devices in usb_device_state_string enum, 153 * the string UNKNOWN will be returned. 154 */ 155 const char *usb_state_string(enum usb_device_state state) 156 { 157 static const char *const names[] = { 158 [USB_STATE_NOTATTACHED] = "not attached", 159 [USB_STATE_ATTACHED] = "attached", 160 [USB_STATE_POWERED] = "powered", 161 [USB_STATE_RECONNECTING] = "reconnecting", 162 [USB_STATE_UNAUTHENTICATED] = "unauthenticated", 163 [USB_STATE_DEFAULT] = "default", 164 [USB_STATE_ADDRESS] = "addressed", 165 [USB_STATE_CONFIGURED] = "configured", 166 [USB_STATE_SUSPENDED] = "suspended", 167 }; 168 169 if (state < 0 || state >= ARRAY_SIZE(names)) 170 return "UNKNOWN"; 171 172 return names[state]; 173 } 174 EXPORT_SYMBOL_GPL(usb_state_string); 175 176 static const char *const usb_dr_modes[] = { 177 [USB_DR_MODE_UNKNOWN] = "", 178 [USB_DR_MODE_HOST] = "host", 179 [USB_DR_MODE_PERIPHERAL] = "peripheral", 180 [USB_DR_MODE_OTG] = "otg", 181 }; 182 183 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str) 184 { 185 int ret; 186 187 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str); 188 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret; 189 } 190 191 enum usb_dr_mode usb_get_dr_mode(struct device *dev) 192 { 193 const char *dr_mode; 194 int err; 195 196 err = device_property_read_string(dev, "dr_mode", &dr_mode); 197 if (err < 0) 198 return USB_DR_MODE_UNKNOWN; 199 200 return usb_get_dr_mode_from_string(dr_mode); 201 } 202 EXPORT_SYMBOL_GPL(usb_get_dr_mode); 203 204 /** 205 * usb_get_role_switch_default_mode - Get default mode for given device 206 * @dev: Pointer to the given device 207 * 208 * The function gets string from property 'role-switch-default-mode', 209 * and returns the corresponding enum usb_dr_mode. 210 */ 211 enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev) 212 { 213 const char *str; 214 int ret; 215 216 ret = device_property_read_string(dev, "role-switch-default-mode", &str); 217 if (ret < 0) 218 return USB_DR_MODE_UNKNOWN; 219 220 return usb_get_dr_mode_from_string(str); 221 } 222 EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode); 223 224 /** 225 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit 226 * @epd: The descriptor of the endpoint 227 * @speed: The speed that the endpoint works as 228 * 229 * Function returns the interval expressed in 1us unit for servicing 230 * endpoint for data transfers. 231 */ 232 unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd, 233 enum usb_device_speed speed) 234 { 235 unsigned int interval = 0; 236 237 switch (usb_endpoint_type(epd)) { 238 case USB_ENDPOINT_XFER_CONTROL: 239 /* uframes per NAK */ 240 if (speed == USB_SPEED_HIGH) 241 interval = epd->bInterval; 242 break; 243 case USB_ENDPOINT_XFER_ISOC: 244 interval = 1 << (epd->bInterval - 1); 245 break; 246 case USB_ENDPOINT_XFER_BULK: 247 /* uframes per NAK */ 248 if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd)) 249 interval = epd->bInterval; 250 break; 251 case USB_ENDPOINT_XFER_INT: 252 if (speed >= USB_SPEED_HIGH) 253 interval = 1 << (epd->bInterval - 1); 254 else 255 interval = epd->bInterval; 256 break; 257 } 258 259 interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000; 260 261 return interval; 262 } 263 EXPORT_SYMBOL_GPL(usb_decode_interval); 264 265 #ifdef CONFIG_OF 266 /** 267 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device 268 * which is associated with the given phy device_node 269 * @np: Pointer to the given phy device_node 270 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for 271 * phys which do not have phy-cells 272 * 273 * In dts a usb controller associates with phy devices. The function gets 274 * the string from property 'dr_mode' of the controller associated with the 275 * given phy device node, and returns the correspondig enum usb_dr_mode. 276 */ 277 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0) 278 { 279 struct device_node *controller = NULL; 280 struct of_phandle_args args; 281 const char *dr_mode; 282 int index; 283 int err; 284 285 do { 286 controller = of_find_node_with_property(controller, "phys"); 287 if (!of_device_is_available(controller)) 288 continue; 289 index = 0; 290 do { 291 if (arg0 == -1) { 292 args.np = of_parse_phandle(controller, "phys", 293 index); 294 args.args_count = 0; 295 } else { 296 err = of_parse_phandle_with_args(controller, 297 "phys", "#phy-cells", 298 index, &args); 299 if (err) 300 break; 301 } 302 303 of_node_put(args.np); 304 if (args.np == np && (args.args_count == 0 || 305 args.args[0] == arg0)) 306 goto finish; 307 index++; 308 } while (args.np); 309 } while (controller); 310 311 finish: 312 err = of_property_read_string(controller, "dr_mode", &dr_mode); 313 of_node_put(controller); 314 315 if (err < 0) 316 return USB_DR_MODE_UNKNOWN; 317 318 return usb_get_dr_mode_from_string(dr_mode); 319 } 320 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy); 321 322 /** 323 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported 324 * for given targeted hosts (non-PC hosts) 325 * @np: Pointer to the given device_node 326 * 327 * The function gets if the targeted hosts support TPL or not 328 */ 329 bool of_usb_host_tpl_support(struct device_node *np) 330 { 331 return of_property_read_bool(np, "tpl-support"); 332 } 333 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support); 334 335 /** 336 * of_usb_update_otg_caps - to update usb otg capabilities according to 337 * the passed properties in DT. 338 * @np: Pointer to the given device_node 339 * @otg_caps: Pointer to the target usb_otg_caps to be set 340 * 341 * The function updates the otg capabilities 342 */ 343 int of_usb_update_otg_caps(struct device_node *np, 344 struct usb_otg_caps *otg_caps) 345 { 346 u32 otg_rev; 347 348 if (!otg_caps) 349 return -EINVAL; 350 351 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) { 352 switch (otg_rev) { 353 case 0x0100: 354 case 0x0120: 355 case 0x0130: 356 case 0x0200: 357 /* Choose the lesser one if it's already been set */ 358 if (otg_caps->otg_rev) 359 otg_caps->otg_rev = min_t(u16, otg_rev, 360 otg_caps->otg_rev); 361 else 362 otg_caps->otg_rev = otg_rev; 363 break; 364 default: 365 pr_err("%pOF: unsupported otg-rev: 0x%x\n", 366 np, otg_rev); 367 return -EINVAL; 368 } 369 } else { 370 /* 371 * otg-rev is mandatory for otg properties, if not passed 372 * we set it to be 0 and assume it's a legacy otg device. 373 * Non-dt platform can set it afterwards. 374 */ 375 otg_caps->otg_rev = 0; 376 } 377 378 if (of_property_read_bool(np, "hnp-disable")) 379 otg_caps->hnp_support = false; 380 if (of_property_read_bool(np, "srp-disable")) 381 otg_caps->srp_support = false; 382 if (of_property_read_bool(np, "adp-disable") || 383 (otg_caps->otg_rev < 0x0200)) 384 otg_caps->adp_support = false; 385 386 return 0; 387 } 388 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps); 389 390 /** 391 * usb_of_get_companion_dev - Find the companion device 392 * @dev: the device pointer to find a companion 393 * 394 * Find the companion device from platform bus. 395 * 396 * Takes a reference to the returned struct device which needs to be dropped 397 * after use. 398 * 399 * Return: On success, a pointer to the companion device, %NULL on failure. 400 */ 401 struct device *usb_of_get_companion_dev(struct device *dev) 402 { 403 struct device_node *node; 404 struct platform_device *pdev = NULL; 405 406 node = of_parse_phandle(dev->of_node, "companion", 0); 407 if (node) 408 pdev = of_find_device_by_node(node); 409 410 of_node_put(node); 411 412 return pdev ? &pdev->dev : NULL; 413 } 414 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev); 415 #endif 416 417 struct dentry *usb_debug_root; 418 EXPORT_SYMBOL_GPL(usb_debug_root); 419 420 static int __init usb_common_init(void) 421 { 422 usb_debug_root = debugfs_create_dir("usb", NULL); 423 ledtrig_usb_init(); 424 return 0; 425 } 426 427 static void __exit usb_common_exit(void) 428 { 429 ledtrig_usb_exit(); 430 debugfs_remove_recursive(usb_debug_root); 431 } 432 433 subsys_initcall(usb_common_init); 434 module_exit(usb_common_exit); 435 436 MODULE_DESCRIPTION("Common code for host and device side USB"); 437 MODULE_LICENSE("GPL"); 438