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 *p = "maximum-speed"; 111 int ret; 112 113 ret = device_property_match_property_string(dev, p, ssp_rate, ARRAY_SIZE(ssp_rate)); 114 if (ret > 0) 115 return USB_SPEED_SUPER_PLUS; 116 117 ret = device_property_match_property_string(dev, p, speed_names, ARRAY_SIZE(speed_names)); 118 if (ret > 0) 119 return ret; 120 121 return USB_SPEED_UNKNOWN; 122 } 123 EXPORT_SYMBOL_GPL(usb_get_maximum_speed); 124 125 /** 126 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count 127 * of a SuperSpeed Plus capable device. 128 * @dev: Pointer to the given USB controller device 129 * 130 * If the string from "maximum-speed" property is super-speed-plus-genXxY where 131 * 'X' is the generation number and 'Y' is the number of lanes, then this 132 * function returns the corresponding enum usb_ssp_rate. 133 */ 134 enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev) 135 { 136 const char *maximum_speed; 137 int ret; 138 139 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed); 140 if (ret < 0) 141 return USB_SSP_GEN_UNKNOWN; 142 143 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed); 144 return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret; 145 } 146 EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate); 147 148 /** 149 * usb_state_string - Returns human readable name for the state. 150 * @state: The state to return a human-readable name for. If it's not 151 * any of the states devices in usb_device_state_string enum, 152 * the string UNKNOWN will be returned. 153 */ 154 const char *usb_state_string(enum usb_device_state state) 155 { 156 static const char *const names[] = { 157 [USB_STATE_NOTATTACHED] = "not attached", 158 [USB_STATE_ATTACHED] = "attached", 159 [USB_STATE_POWERED] = "powered", 160 [USB_STATE_RECONNECTING] = "reconnecting", 161 [USB_STATE_UNAUTHENTICATED] = "unauthenticated", 162 [USB_STATE_DEFAULT] = "default", 163 [USB_STATE_ADDRESS] = "addressed", 164 [USB_STATE_CONFIGURED] = "configured", 165 [USB_STATE_SUSPENDED] = "suspended", 166 }; 167 168 if (state < 0 || state >= ARRAY_SIZE(names)) 169 return "UNKNOWN"; 170 171 return names[state]; 172 } 173 EXPORT_SYMBOL_GPL(usb_state_string); 174 175 static const char *const usb_dr_modes[] = { 176 [USB_DR_MODE_UNKNOWN] = "", 177 [USB_DR_MODE_HOST] = "host", 178 [USB_DR_MODE_PERIPHERAL] = "peripheral", 179 [USB_DR_MODE_OTG] = "otg", 180 }; 181 182 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str) 183 { 184 int ret; 185 186 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str); 187 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret; 188 } 189 190 enum usb_dr_mode usb_get_dr_mode(struct device *dev) 191 { 192 const char *dr_mode; 193 int err; 194 195 err = device_property_read_string(dev, "dr_mode", &dr_mode); 196 if (err < 0) 197 return USB_DR_MODE_UNKNOWN; 198 199 return usb_get_dr_mode_from_string(dr_mode); 200 } 201 EXPORT_SYMBOL_GPL(usb_get_dr_mode); 202 203 /** 204 * usb_get_role_switch_default_mode - Get default mode for given device 205 * @dev: Pointer to the given device 206 * 207 * The function gets string from property 'role-switch-default-mode', 208 * and returns the corresponding enum usb_dr_mode. 209 */ 210 enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev) 211 { 212 const char *str; 213 int ret; 214 215 ret = device_property_read_string(dev, "role-switch-default-mode", &str); 216 if (ret < 0) 217 return USB_DR_MODE_UNKNOWN; 218 219 return usb_get_dr_mode_from_string(str); 220 } 221 EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode); 222 223 /** 224 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit 225 * @epd: The descriptor of the endpoint 226 * @speed: The speed that the endpoint works as 227 * 228 * Function returns the interval expressed in 1us unit for servicing 229 * endpoint for data transfers. 230 */ 231 unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd, 232 enum usb_device_speed speed) 233 { 234 unsigned int interval = 0; 235 236 switch (usb_endpoint_type(epd)) { 237 case USB_ENDPOINT_XFER_CONTROL: 238 /* uframes per NAK */ 239 if (speed == USB_SPEED_HIGH) 240 interval = epd->bInterval; 241 break; 242 case USB_ENDPOINT_XFER_ISOC: 243 interval = 1 << (epd->bInterval - 1); 244 break; 245 case USB_ENDPOINT_XFER_BULK: 246 /* uframes per NAK */ 247 if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd)) 248 interval = epd->bInterval; 249 break; 250 case USB_ENDPOINT_XFER_INT: 251 if (speed >= USB_SPEED_HIGH) 252 interval = 1 << (epd->bInterval - 1); 253 else 254 interval = epd->bInterval; 255 break; 256 } 257 258 interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000; 259 260 return interval; 261 } 262 EXPORT_SYMBOL_GPL(usb_decode_interval); 263 264 #ifdef CONFIG_OF 265 /** 266 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device 267 * which is associated with the given phy device_node 268 * @np: Pointer to the given phy device_node 269 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for 270 * phys which do not have phy-cells 271 * 272 * In dts a usb controller associates with phy devices. The function gets 273 * the string from property 'dr_mode' of the controller associated with the 274 * given phy device node, and returns the correspondig enum usb_dr_mode. 275 */ 276 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0) 277 { 278 struct device_node *controller; 279 struct of_phandle_args args; 280 const char *dr_mode; 281 int index; 282 int err; 283 284 for_each_node_with_property(controller, "phys") { 285 if (!of_device_is_available(controller)) 286 continue; 287 index = 0; 288 do { 289 if (arg0 == -1) { 290 args.np = of_parse_phandle(controller, "phys", 291 index); 292 args.args_count = 0; 293 } else { 294 err = of_parse_phandle_with_args(controller, 295 "phys", "#phy-cells", 296 index, &args); 297 if (err) 298 break; 299 } 300 301 of_node_put(args.np); 302 if (args.np == np && (args.args_count == 0 || 303 args.args[0] == arg0)) 304 goto finish; 305 index++; 306 } while (args.np); 307 } 308 309 finish: 310 err = of_property_read_string(controller, "dr_mode", &dr_mode); 311 of_node_put(controller); 312 313 if (err < 0) 314 return USB_DR_MODE_UNKNOWN; 315 316 return usb_get_dr_mode_from_string(dr_mode); 317 } 318 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy); 319 320 /** 321 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported 322 * for given targeted hosts (non-PC hosts) 323 * @np: Pointer to the given device_node 324 * 325 * The function gets if the targeted hosts support TPL or not 326 */ 327 bool of_usb_host_tpl_support(struct device_node *np) 328 { 329 return of_property_read_bool(np, "tpl-support"); 330 } 331 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support); 332 333 /** 334 * of_usb_update_otg_caps - to update usb otg capabilities according to 335 * the passed properties in DT. 336 * @np: Pointer to the given device_node 337 * @otg_caps: Pointer to the target usb_otg_caps to be set 338 * 339 * The function updates the otg capabilities 340 */ 341 int of_usb_update_otg_caps(struct device_node *np, 342 struct usb_otg_caps *otg_caps) 343 { 344 u32 otg_rev; 345 346 if (!otg_caps) 347 return -EINVAL; 348 349 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) { 350 switch (otg_rev) { 351 case 0x0100: 352 case 0x0120: 353 case 0x0130: 354 case 0x0200: 355 /* Choose the lesser one if it's already been set */ 356 if (otg_caps->otg_rev) 357 otg_caps->otg_rev = min_t(u16, otg_rev, 358 otg_caps->otg_rev); 359 else 360 otg_caps->otg_rev = otg_rev; 361 break; 362 default: 363 pr_err("%pOF: unsupported otg-rev: 0x%x\n", 364 np, otg_rev); 365 return -EINVAL; 366 } 367 } else { 368 /* 369 * otg-rev is mandatory for otg properties, if not passed 370 * we set it to be 0 and assume it's a legacy otg device. 371 * Non-dt platform can set it afterwards. 372 */ 373 otg_caps->otg_rev = 0; 374 } 375 376 if (of_property_read_bool(np, "hnp-disable")) 377 otg_caps->hnp_support = false; 378 if (of_property_read_bool(np, "srp-disable")) 379 otg_caps->srp_support = false; 380 if (of_property_read_bool(np, "adp-disable") || 381 (otg_caps->otg_rev < 0x0200)) 382 otg_caps->adp_support = false; 383 384 return 0; 385 } 386 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps); 387 388 /** 389 * usb_of_get_companion_dev - Find the companion device 390 * @dev: the device pointer to find a companion 391 * 392 * Find the companion device from platform bus. 393 * 394 * Takes a reference to the returned struct device which needs to be dropped 395 * after use. 396 * 397 * Return: On success, a pointer to the companion device, %NULL on failure. 398 */ 399 struct device *usb_of_get_companion_dev(struct device *dev) 400 { 401 struct device_node *node; 402 struct platform_device *pdev = NULL; 403 404 node = of_parse_phandle(dev->of_node, "companion", 0); 405 if (node) 406 pdev = of_find_device_by_node(node); 407 408 of_node_put(node); 409 410 return pdev ? &pdev->dev : NULL; 411 } 412 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev); 413 #endif 414 415 struct dentry *usb_debug_root; 416 EXPORT_SYMBOL_GPL(usb_debug_root); 417 418 static int __init usb_common_init(void) 419 { 420 usb_debug_root = debugfs_create_dir("usb", NULL); 421 ledtrig_usb_init(); 422 return 0; 423 } 424 425 static void __exit usb_common_exit(void) 426 { 427 ledtrig_usb_exit(); 428 debugfs_remove_recursive(usb_debug_root); 429 } 430 431 subsys_initcall(usb_common_init); 432 module_exit(usb_common_exit); 433 434 MODULE_DESCRIPTION("Common code for host and device side USB"); 435 MODULE_LICENSE("GPL"); 436