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