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/usb/ch9.h> 15 #include <linux/usb/of.h> 16 #include <linux/usb/otg.h> 17 #include <linux/of_platform.h> 18 19 const char *usb_otg_state_string(enum usb_otg_state state) 20 { 21 static const char *const names[] = { 22 [OTG_STATE_A_IDLE] = "a_idle", 23 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise", 24 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon", 25 [OTG_STATE_A_HOST] = "a_host", 26 [OTG_STATE_A_SUSPEND] = "a_suspend", 27 [OTG_STATE_A_PERIPHERAL] = "a_peripheral", 28 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall", 29 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err", 30 [OTG_STATE_B_IDLE] = "b_idle", 31 [OTG_STATE_B_SRP_INIT] = "b_srp_init", 32 [OTG_STATE_B_PERIPHERAL] = "b_peripheral", 33 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon", 34 [OTG_STATE_B_HOST] = "b_host", 35 }; 36 37 if (state < 0 || state >= ARRAY_SIZE(names)) 38 return "UNDEFINED"; 39 40 return names[state]; 41 } 42 EXPORT_SYMBOL_GPL(usb_otg_state_string); 43 44 static const char *const speed_names[] = { 45 [USB_SPEED_UNKNOWN] = "UNKNOWN", 46 [USB_SPEED_LOW] = "low-speed", 47 [USB_SPEED_FULL] = "full-speed", 48 [USB_SPEED_HIGH] = "high-speed", 49 [USB_SPEED_WIRELESS] = "wireless", 50 [USB_SPEED_SUPER] = "super-speed", 51 [USB_SPEED_SUPER_PLUS] = "super-speed-plus", 52 }; 53 54 const char *usb_speed_string(enum usb_device_speed speed) 55 { 56 if (speed < 0 || speed >= ARRAY_SIZE(speed_names)) 57 speed = USB_SPEED_UNKNOWN; 58 return speed_names[speed]; 59 } 60 EXPORT_SYMBOL_GPL(usb_speed_string); 61 62 enum usb_device_speed usb_get_maximum_speed(struct device *dev) 63 { 64 const char *maximum_speed; 65 int ret; 66 67 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed); 68 if (ret < 0) 69 return USB_SPEED_UNKNOWN; 70 71 ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed); 72 73 return (ret < 0) ? USB_SPEED_UNKNOWN : ret; 74 } 75 EXPORT_SYMBOL_GPL(usb_get_maximum_speed); 76 77 const char *usb_state_string(enum usb_device_state state) 78 { 79 static const char *const names[] = { 80 [USB_STATE_NOTATTACHED] = "not attached", 81 [USB_STATE_ATTACHED] = "attached", 82 [USB_STATE_POWERED] = "powered", 83 [USB_STATE_RECONNECTING] = "reconnecting", 84 [USB_STATE_UNAUTHENTICATED] = "unauthenticated", 85 [USB_STATE_DEFAULT] = "default", 86 [USB_STATE_ADDRESS] = "addressed", 87 [USB_STATE_CONFIGURED] = "configured", 88 [USB_STATE_SUSPENDED] = "suspended", 89 }; 90 91 if (state < 0 || state >= ARRAY_SIZE(names)) 92 return "UNKNOWN"; 93 94 return names[state]; 95 } 96 EXPORT_SYMBOL_GPL(usb_state_string); 97 98 static const char *const usb_dr_modes[] = { 99 [USB_DR_MODE_UNKNOWN] = "", 100 [USB_DR_MODE_HOST] = "host", 101 [USB_DR_MODE_PERIPHERAL] = "peripheral", 102 [USB_DR_MODE_OTG] = "otg", 103 }; 104 105 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str) 106 { 107 int ret; 108 109 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str); 110 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret; 111 } 112 113 enum usb_dr_mode usb_get_dr_mode(struct device *dev) 114 { 115 const char *dr_mode; 116 int err; 117 118 err = device_property_read_string(dev, "dr_mode", &dr_mode); 119 if (err < 0) 120 return USB_DR_MODE_UNKNOWN; 121 122 return usb_get_dr_mode_from_string(dr_mode); 123 } 124 EXPORT_SYMBOL_GPL(usb_get_dr_mode); 125 126 #ifdef CONFIG_OF 127 /** 128 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device 129 * which is associated with the given phy device_node 130 * @np: Pointer to the given phy device_node 131 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for 132 * phys which do not have phy-cells 133 * 134 * In dts a usb controller associates with phy devices. The function gets 135 * the string from property 'dr_mode' of the controller associated with the 136 * given phy device node, and returns the correspondig enum usb_dr_mode. 137 */ 138 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0) 139 { 140 struct device_node *controller = NULL; 141 struct of_phandle_args args; 142 const char *dr_mode; 143 int index; 144 int err; 145 146 do { 147 controller = of_find_node_with_property(controller, "phys"); 148 index = 0; 149 do { 150 if (arg0 == -1) { 151 args.np = of_parse_phandle(controller, "phys", 152 index); 153 args.args_count = 0; 154 } else { 155 err = of_parse_phandle_with_args(controller, 156 "phys", "#phy-cells", 157 index, &args); 158 if (err) 159 break; 160 } 161 162 of_node_put(args.np); 163 if (args.np == np && (args.args_count == 0 || 164 args.args[0] == arg0)) 165 goto finish; 166 index++; 167 } while (args.np); 168 } while (controller); 169 170 finish: 171 err = of_property_read_string(controller, "dr_mode", &dr_mode); 172 of_node_put(controller); 173 174 if (err < 0) 175 return USB_DR_MODE_UNKNOWN; 176 177 return usb_get_dr_mode_from_string(dr_mode); 178 } 179 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy); 180 181 /** 182 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported 183 * for given targeted hosts (non-PC hosts) 184 * @np: Pointer to the given device_node 185 * 186 * The function gets if the targeted hosts support TPL or not 187 */ 188 bool of_usb_host_tpl_support(struct device_node *np) 189 { 190 return of_property_read_bool(np, "tpl-support"); 191 } 192 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support); 193 194 /** 195 * of_usb_update_otg_caps - to update usb otg capabilities according to 196 * the passed properties in DT. 197 * @np: Pointer to the given device_node 198 * @otg_caps: Pointer to the target usb_otg_caps to be set 199 * 200 * The function updates the otg capabilities 201 */ 202 int of_usb_update_otg_caps(struct device_node *np, 203 struct usb_otg_caps *otg_caps) 204 { 205 u32 otg_rev; 206 207 if (!otg_caps) 208 return -EINVAL; 209 210 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) { 211 switch (otg_rev) { 212 case 0x0100: 213 case 0x0120: 214 case 0x0130: 215 case 0x0200: 216 /* Choose the lesser one if it's already been set */ 217 if (otg_caps->otg_rev) 218 otg_caps->otg_rev = min_t(u16, otg_rev, 219 otg_caps->otg_rev); 220 else 221 otg_caps->otg_rev = otg_rev; 222 break; 223 default: 224 pr_err("%pOF: unsupported otg-rev: 0x%x\n", 225 np, otg_rev); 226 return -EINVAL; 227 } 228 } else { 229 /* 230 * otg-rev is mandatory for otg properties, if not passed 231 * we set it to be 0 and assume it's a legacy otg device. 232 * Non-dt platform can set it afterwards. 233 */ 234 otg_caps->otg_rev = 0; 235 } 236 237 if (of_property_read_bool(np, "hnp-disable")) 238 otg_caps->hnp_support = false; 239 if (of_property_read_bool(np, "srp-disable")) 240 otg_caps->srp_support = false; 241 if (of_property_read_bool(np, "adp-disable") || 242 (otg_caps->otg_rev < 0x0200)) 243 otg_caps->adp_support = false; 244 245 return 0; 246 } 247 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps); 248 249 /** 250 * usb_of_get_companion_dev - Find the companion device 251 * @dev: the device pointer to find a companion 252 * 253 * Find the companion device from platform bus. 254 * 255 * Takes a reference to the returned struct device which needs to be dropped 256 * after use. 257 * 258 * Return: On success, a pointer to the companion device, %NULL on failure. 259 */ 260 struct device *usb_of_get_companion_dev(struct device *dev) 261 { 262 struct device_node *node; 263 struct platform_device *pdev = NULL; 264 265 node = of_parse_phandle(dev->of_node, "companion", 0); 266 if (node) 267 pdev = of_find_device_by_node(node); 268 269 of_node_put(node); 270 271 return pdev ? &pdev->dev : NULL; 272 } 273 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev); 274 #endif 275 276 MODULE_LICENSE("GPL"); 277