drivers/usb/common/common.c

   1 /*
   2  * Provides code common for host and device side USB.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation, version 2.
   7  *
   8  * If either host side (ie. CONFIG_USB=y) or device side USB stack
   9  * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
  10  * compiled-in as well.  Otherwise, if either of the two stacks is
  11  * compiled as module, this file is compiled as module as well.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/of.h>
  17 #include <linux/usb/ch9.h>
  18 #include <linux/usb/of.h>
  19 #include <linux/usb/otg.h>
  20 #include <linux/of_platform.h>
  21
  22 const char *usb_otg_state_string(enum usb_otg_state state)
  23 {
  24         static const char *const names[] = {
  25                 [OTG_STATE_A_IDLE] = "a_idle",
  26                 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
  27                 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
  28                 [OTG_STATE_A_HOST] = "a_host",
  29                 [OTG_STATE_A_SUSPEND] = "a_suspend",
  30                 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
  31                 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
  32                 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
  33                 [OTG_STATE_B_IDLE] = "b_idle",
  34                 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
  35                 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
  36                 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
  37                 [OTG_STATE_B_HOST] = "b_host",
  38         };
  39
  40         if (state < 0 || state >= ARRAY_SIZE(names))
  41                 return "UNDEFINED";
  42
  43         return names[state];
  44 }
  45 EXPORT_SYMBOL_GPL(usb_otg_state_string);
  46
  47 static const char *const speed_names[] = {
  48         [USB_SPEED_UNKNOWN] = "UNKNOWN",
  49         [USB_SPEED_LOW] = "low-speed",
  50         [USB_SPEED_FULL] = "full-speed",
  51         [USB_SPEED_HIGH] = "high-speed",
  52         [USB_SPEED_WIRELESS] = "wireless",
  53         [USB_SPEED_SUPER] = "super-speed",
  54         [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
  55 };
  56
  57 const char *usb_speed_string(enum usb_device_speed speed)
  58 {
  59         if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
  60                 speed = USB_SPEED_UNKNOWN;
  61         return speed_names[speed];
  62 }
  63 EXPORT_SYMBOL_GPL(usb_speed_string);
  64
  65 enum usb_device_speed usb_get_maximum_speed(struct device *dev)
  66 {
  67         const char *maximum_speed;
  68         int ret;
  69
  70         ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
  71         if (ret < 0)
  72                 return USB_SPEED_UNKNOWN;
  73
  74         ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
  75
  76         return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
  77 }
  78 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
  79
  80 const char *usb_state_string(enum usb_device_state state)
  81 {
  82         static const char *const names[] = {
  83                 [USB_STATE_NOTATTACHED] = "not attached",
  84                 [USB_STATE_ATTACHED] = "attached",
  85                 [USB_STATE_POWERED] = "powered",
  86                 [USB_STATE_RECONNECTING] = "reconnecting",
  87                 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
  88                 [USB_STATE_DEFAULT] = "default",
  89                 [USB_STATE_ADDRESS] = "addressed",
  90                 [USB_STATE_CONFIGURED] = "configured",
  91                 [USB_STATE_SUSPENDED] = "suspended",
  92         };
  93
  94         if (state < 0 || state >= ARRAY_SIZE(names))
  95                 return "UNKNOWN";
  96
  97         return names[state];
  98 }
  99 EXPORT_SYMBOL_GPL(usb_state_string);
 100
 101 static const char *const usb_dr_modes[] = {
 102         [USB_DR_MODE_UNKNOWN]           = "",
 103         [USB_DR_MODE_HOST]              = "host",
 104         [USB_DR_MODE_PERIPHERAL]        = "peripheral",
 105         [USB_DR_MODE_OTG]               = "otg",
 106 };
 107
 108 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
 109 {
 110         int ret;
 111
 112         ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
 113         return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
 114 }
 115
 116 enum usb_dr_mode usb_get_dr_mode(struct device *dev)
 117 {
 118         const char *dr_mode;
 119         int err;
 120
 121         err = device_property_read_string(dev, "dr_mode", &dr_mode);
 122         if (err < 0)
 123                 return USB_DR_MODE_UNKNOWN;
 124
 125         return usb_get_dr_mode_from_string(dr_mode);
 126 }
 127 EXPORT_SYMBOL_GPL(usb_get_dr_mode);
 128
 129 #ifdef CONFIG_OF
 130 /**
 131  * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
 132  * which is associated with the given phy device_node
 133  * @np: Pointer to the given phy device_node
 134  * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
 135  *        phys which do not have phy-cells
 136  *
 137  * In dts a usb controller associates with phy devices.  The function gets
 138  * the string from property 'dr_mode' of the controller associated with the
 139  * given phy device node, and returns the correspondig enum usb_dr_mode.
 140  */
 141 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
 142 {
 143         struct device_node *controller = NULL;
 144         struct of_phandle_args args;
 145         const char *dr_mode;
 146         int index;
 147         int err;
 148
 149         do {
 150                 controller = of_find_node_with_property(controller, "phys");
 151                 if (!of_device_is_available(controller))
 152                         continue;
 153                 index = 0;
 154                 do {
 155                         if (arg0 == -1) {
 156                                 args.np = of_parse_phandle(controller, "phys",
 157                                                         index);
 158                                 args.args_count = 0;
 159                         } else {
 160                                 err = of_parse_phandle_with_args(controller,
 161                                                         "phys", "#phy-cells",
 162                                                         index, &args);
 163                                 if (err)
 164                                         break;
 165                         }
 166
 167                         of_node_put(args.np);
 168                         if (args.np == np && (args.args_count == 0 ||
 169                                               args.args[0] == arg0))
 170                                 goto finish;
 171                         index++;
 172                 } while (args.np);
 173         } while (controller);
 174
 175 finish:
 176         err = of_property_read_string(controller, "dr_mode", &dr_mode);
 177         of_node_put(controller);
 178
 179         if (err < 0)
 180                 return USB_DR_MODE_UNKNOWN;
 181
 182         return usb_get_dr_mode_from_string(dr_mode);
 183 }
 184 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
 185
 186 /**
 187  * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 188  * for given targeted hosts (non-PC hosts)
 189  * @np: Pointer to the given device_node
 190  *
 191  * The function gets if the targeted hosts support TPL or not
 192  */
 193 bool of_usb_host_tpl_support(struct device_node *np)
 194 {
 195         if (of_find_property(np, "tpl-support", NULL))
 196                 return true;
 197
 198         return false;
 199 }
 200 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 201
 202 /**
 203  * of_usb_update_otg_caps - to update usb otg capabilities according to
 204  * the passed properties in DT.
 205  * @np: Pointer to the given device_node
 206  * @otg_caps: Pointer to the target usb_otg_caps to be set
 207  *
 208  * The function updates the otg capabilities
 209  */
 210 int of_usb_update_otg_caps(struct device_node *np,
 211                         struct usb_otg_caps *otg_caps)
 212 {
 213         u32 otg_rev;
 214
 215         if (!otg_caps)
 216                 return -EINVAL;
 217
 218         if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
 219                 switch (otg_rev) {
 220                 case 0x0100:
 221                 case 0x0120:
 222                 case 0x0130:
 223                 case 0x0200:
 224                         /* Choose the lesser one if it's already been set */
 225                         if (otg_caps->otg_rev)
 226                                 otg_caps->otg_rev = min_t(u16, otg_rev,
 227                                                         otg_caps->otg_rev);
 228                         else
 229                                 otg_caps->otg_rev = otg_rev;
 230                         break;
 231                 default:
 232                         pr_err("%s: unsupported otg-rev: 0x%x\n",
 233                                                 np->full_name, otg_rev);
 234                         return -EINVAL;
 235                 }
 236         } else {
 237                 /*
 238                  * otg-rev is mandatory for otg properties, if not passed
 239                  * we set it to be 0 and assume it's a legacy otg device.
 240                  * Non-dt platform can set it afterwards.
 241                  */
 242                 otg_caps->otg_rev = 0;
 243         }
 244
 245         if (of_find_property(np, "hnp-disable", NULL))
 246                 otg_caps->hnp_support = false;
 247         if (of_find_property(np, "srp-disable", NULL))
 248                 otg_caps->srp_support = false;
 249         if (of_find_property(np, "adp-disable", NULL) ||
 250                                 (otg_caps->otg_rev < 0x0200))
 251                 otg_caps->adp_support = false;
 252
 253         return 0;
 254 }
 255 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
 256
 257 #endif
 258
 259 MODULE_LICENSE("GPL");