drivers/usb/common/common.c

   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 #include <linux/debugfs.h>
  19 #include "common.h"
  20
  21 static const char *const ep_type_names[] = {
  22         [USB_ENDPOINT_XFER_CONTROL] = "ctrl",
  23         [USB_ENDPOINT_XFER_ISOC] = "isoc",
  24         [USB_ENDPOINT_XFER_BULK] = "bulk",
  25         [USB_ENDPOINT_XFER_INT] = "intr",
  26 };
  27
  28 const char *usb_ep_type_string(int ep_type)
  29 {
  30         if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
  31                 return "unknown";
  32
  33         return ep_type_names[ep_type];
  34 }
  35 EXPORT_SYMBOL_GPL(usb_ep_type_string);
  36
  37 const char *usb_otg_state_string(enum usb_otg_state state)
  38 {
  39         static const char *const names[] = {
  40                 [OTG_STATE_A_IDLE] = "a_idle",
  41                 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
  42                 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
  43                 [OTG_STATE_A_HOST] = "a_host",
  44                 [OTG_STATE_A_SUSPEND] = "a_suspend",
  45                 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
  46                 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
  47                 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
  48                 [OTG_STATE_B_IDLE] = "b_idle",
  49                 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
  50                 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
  51                 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
  52                 [OTG_STATE_B_HOST] = "b_host",
  53         };
  54
  55         if (state < 0 || state >= ARRAY_SIZE(names))
  56                 return "UNDEFINED";
  57
  58         return names[state];
  59 }
  60 EXPORT_SYMBOL_GPL(usb_otg_state_string);
  61
  62 static const char *const speed_names[] = {
  63         [USB_SPEED_UNKNOWN] = "UNKNOWN",
  64         [USB_SPEED_LOW] = "low-speed",
  65         [USB_SPEED_FULL] = "full-speed",
  66         [USB_SPEED_HIGH] = "high-speed",
  67         [USB_SPEED_WIRELESS] = "wireless",
  68         [USB_SPEED_SUPER] = "super-speed",
  69         [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
  70 };
  71
  72 static const char *const ssp_rate[] = {
  73         [USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
  74         [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
  75         [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
  76         [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
  77 };
  78
  79 const char *usb_speed_string(enum usb_device_speed speed)
  80 {
  81         if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
  82                 speed = USB_SPEED_UNKNOWN;
  83         return speed_names[speed];
  84 }
  85 EXPORT_SYMBOL_GPL(usb_speed_string);
  86
  87 enum usb_device_speed usb_get_maximum_speed(struct device *dev)
  88 {
  89         const char *maximum_speed;
  90         int ret;
  91
  92         ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
  93         if (ret < 0)
  94                 return USB_SPEED_UNKNOWN;
  95
  96         ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
  97         if (ret > 0)
  98                 return USB_SPEED_SUPER_PLUS;
  99
 100         ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
 101         return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
 102 }
 103 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
 104
 105 enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
 106 {
 107         const char *maximum_speed;
 108         int ret;
 109
 110         ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
 111         if (ret < 0)
 112                 return USB_SSP_GEN_UNKNOWN;
 113
 114         ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
 115         return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
 116 }
 117 EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
 118
 119 const char *usb_state_string(enum usb_device_state state)
 120 {
 121         static const char *const names[] = {
 122                 [USB_STATE_NOTATTACHED] = "not attached",
 123                 [USB_STATE_ATTACHED] = "attached",
 124                 [USB_STATE_POWERED] = "powered",
 125                 [USB_STATE_RECONNECTING] = "reconnecting",
 126                 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
 127                 [USB_STATE_DEFAULT] = "default",
 128                 [USB_STATE_ADDRESS] = "addressed",
 129                 [USB_STATE_CONFIGURED] = "configured",
 130                 [USB_STATE_SUSPENDED] = "suspended",
 131         };
 132
 133         if (state < 0 || state >= ARRAY_SIZE(names))
 134                 return "UNKNOWN";
 135
 136         return names[state];
 137 }
 138 EXPORT_SYMBOL_GPL(usb_state_string);
 139
 140 static const char *const usb_dr_modes[] = {
 141         [USB_DR_MODE_UNKNOWN]           = "",
 142         [USB_DR_MODE_HOST]              = "host",
 143         [USB_DR_MODE_PERIPHERAL]        = "peripheral",
 144         [USB_DR_MODE_OTG]               = "otg",
 145 };
 146
 147 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
 148 {
 149         int ret;
 150
 151         ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
 152         return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
 153 }
 154
 155 enum usb_dr_mode usb_get_dr_mode(struct device *dev)
 156 {
 157         const char *dr_mode;
 158         int err;
 159
 160         err = device_property_read_string(dev, "dr_mode", &dr_mode);
 161         if (err < 0)
 162                 return USB_DR_MODE_UNKNOWN;
 163
 164         return usb_get_dr_mode_from_string(dr_mode);
 165 }
 166 EXPORT_SYMBOL_GPL(usb_get_dr_mode);
 167
 168 #ifdef CONFIG_OF
 169 /**
 170  * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
 171  * which is associated with the given phy device_node
 172  * @np: Pointer to the given phy device_node
 173  * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
 174  *        phys which do not have phy-cells
 175  *
 176  * In dts a usb controller associates with phy devices.  The function gets
 177  * the string from property 'dr_mode' of the controller associated with the
 178  * given phy device node, and returns the correspondig enum usb_dr_mode.
 179  */
 180 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
 181 {
 182         struct device_node *controller = NULL;
 183         struct of_phandle_args args;
 184         const char *dr_mode;
 185         int index;
 186         int err;
 187
 188         do {
 189                 controller = of_find_node_with_property(controller, "phys");
 190                 if (!of_device_is_available(controller))
 191                         continue;
 192                 index = 0;
 193                 do {
 194                         if (arg0 == -1) {
 195                                 args.np = of_parse_phandle(controller, "phys",
 196                                                         index);
 197                                 args.args_count = 0;
 198                         } else {
 199                                 err = of_parse_phandle_with_args(controller,
 200                                                         "phys", "#phy-cells",
 201                                                         index, &args);
 202                                 if (err)
 203                                         break;
 204                         }
 205
 206                         of_node_put(args.np);
 207                         if (args.np == np && (args.args_count == 0 ||
 208                                               args.args[0] == arg0))
 209                                 goto finish;
 210                         index++;
 211                 } while (args.np);
 212         } while (controller);
 213
 214 finish:
 215         err = of_property_read_string(controller, "dr_mode", &dr_mode);
 216         of_node_put(controller);
 217
 218         if (err < 0)
 219                 return USB_DR_MODE_UNKNOWN;
 220
 221         return usb_get_dr_mode_from_string(dr_mode);
 222 }
 223 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
 224
 225 /**
 226  * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 227  * for given targeted hosts (non-PC hosts)
 228  * @np: Pointer to the given device_node
 229  *
 230  * The function gets if the targeted hosts support TPL or not
 231  */
 232 bool of_usb_host_tpl_support(struct device_node *np)
 233 {
 234         return of_property_read_bool(np, "tpl-support");
 235 }
 236 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 237
 238 /**
 239  * of_usb_update_otg_caps - to update usb otg capabilities according to
 240  * the passed properties in DT.
 241  * @np: Pointer to the given device_node
 242  * @otg_caps: Pointer to the target usb_otg_caps to be set
 243  *
 244  * The function updates the otg capabilities
 245  */
 246 int of_usb_update_otg_caps(struct device_node *np,
 247                         struct usb_otg_caps *otg_caps)
 248 {
 249         u32 otg_rev;
 250
 251         if (!otg_caps)
 252                 return -EINVAL;
 253
 254         if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
 255                 switch (otg_rev) {
 256                 case 0x0100:
 257                 case 0x0120:
 258                 case 0x0130:
 259                 case 0x0200:
 260                         /* Choose the lesser one if it's already been set */
 261                         if (otg_caps->otg_rev)
 262                                 otg_caps->otg_rev = min_t(u16, otg_rev,
 263                                                         otg_caps->otg_rev);
 264                         else
 265                                 otg_caps->otg_rev = otg_rev;
 266                         break;
 267                 default:
 268                         pr_err("%pOF: unsupported otg-rev: 0x%x\n",
 269                                                 np, otg_rev);
 270                         return -EINVAL;
 271                 }
 272         } else {
 273                 /*
 274                  * otg-rev is mandatory for otg properties, if not passed
 275                  * we set it to be 0 and assume it's a legacy otg device.
 276                  * Non-dt platform can set it afterwards.
 277                  */
 278                 otg_caps->otg_rev = 0;
 279         }
 280
 281         if (of_property_read_bool(np, "hnp-disable"))
 282                 otg_caps->hnp_support = false;
 283         if (of_property_read_bool(np, "srp-disable"))
 284                 otg_caps->srp_support = false;
 285         if (of_property_read_bool(np, "adp-disable") ||
 286                                 (otg_caps->otg_rev < 0x0200))
 287                 otg_caps->adp_support = false;
 288
 289         return 0;
 290 }
 291 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
 292
 293 /**
 294  * usb_of_get_companion_dev - Find the companion device
 295  * @dev: the device pointer to find a companion
 296  *
 297  * Find the companion device from platform bus.
 298  *
 299  * Takes a reference to the returned struct device which needs to be dropped
 300  * after use.
 301  *
 302  * Return: On success, a pointer to the companion device, %NULL on failure.
 303  */
 304 struct device *usb_of_get_companion_dev(struct device *dev)
 305 {
 306         struct device_node *node;
 307         struct platform_device *pdev = NULL;
 308
 309         node = of_parse_phandle(dev->of_node, "companion", 0);
 310         if (node)
 311                 pdev = of_find_device_by_node(node);
 312
 313         of_node_put(node);
 314
 315         return pdev ? &pdev->dev : NULL;
 316 }
 317 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
 318 #endif
 319
 320 struct dentry *usb_debug_root;
 321 EXPORT_SYMBOL_GPL(usb_debug_root);
 322
 323 static int __init usb_common_init(void)
 324 {
 325         usb_debug_root = debugfs_create_dir("usb", NULL);
 326         ledtrig_usb_init();
 327         return 0;
 328 }
 329
 330 static void __exit usb_common_exit(void)
 331 {
 332         ledtrig_usb_exit();
 333         debugfs_remove_recursive(usb_debug_root);
 334 }
 335
 336 subsys_initcall(usb_common_init);
 337 module_exit(usb_common_exit);
 338
 339 MODULE_LICENSE("GPL");