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  *
 135  * In dts a usb controller associates with phy devices.  The function gets
 136  * the string from property 'dr_mode' of the controller associated with the
 137  * given phy device node, and returns the correspondig enum usb_dr_mode.
 138  */
 139 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np)
 140 {
 141         struct device_node *controller = NULL;
 142         struct device_node *phy;
 143         const char *dr_mode;
 144         int index;
 145         int err;
 146
 147         do {
 148                 controller = of_find_node_with_property(controller, "phys");
 149                 index = 0;
 150                 do {
 151                         phy = of_parse_phandle(controller, "phys", index);
 152                         of_node_put(phy);
 153                         if (phy == phy_np)
 154                                 goto finish;
 155                         index++;
 156                 } while (phy);
 157         } while (controller);
 158
 159 finish:
 160         err = of_property_read_string(controller, "dr_mode", &dr_mode);
 161         of_node_put(controller);
 162
 163         if (err < 0)
 164                 return USB_DR_MODE_UNKNOWN;
 165
 166         return usb_get_dr_mode_from_string(dr_mode);
 167 }
 168 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
 169
 170 /**
 171  * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 172  * for given targeted hosts (non-PC hosts)
 173  * @np: Pointer to the given device_node
 174  *
 175  * The function gets if the targeted hosts support TPL or not
 176  */
 177 bool of_usb_host_tpl_support(struct device_node *np)
 178 {
 179         if (of_find_property(np, "tpl-support", NULL))
 180                 return true;
 181
 182         return false;
 183 }
 184 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 185
 186 /**
 187  * of_usb_update_otg_caps - to update usb otg capabilities according to
 188  * the passed properties in DT.
 189  * @np: Pointer to the given device_node
 190  * @otg_caps: Pointer to the target usb_otg_caps to be set
 191  *
 192  * The function updates the otg capabilities
 193  */
 194 int of_usb_update_otg_caps(struct device_node *np,
 195                         struct usb_otg_caps *otg_caps)
 196 {
 197         u32 otg_rev;
 198
 199         if (!otg_caps)
 200                 return -EINVAL;
 201
 202         if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
 203                 switch (otg_rev) {
 204                 case 0x0100:
 205                 case 0x0120:
 206                 case 0x0130:
 207                 case 0x0200:
 208                         /* Choose the lesser one if it's already been set */
 209                         if (otg_caps->otg_rev)
 210                                 otg_caps->otg_rev = min_t(u16, otg_rev,
 211                                                         otg_caps->otg_rev);
 212                         else
 213                                 otg_caps->otg_rev = otg_rev;
 214                         break;
 215                 default:
 216                         pr_err("%s: unsupported otg-rev: 0x%x\n",
 217                                                 np->full_name, otg_rev);
 218                         return -EINVAL;
 219                 }
 220         } else {
 221                 /*
 222                  * otg-rev is mandatory for otg properties, if not passed
 223                  * we set it to be 0 and assume it's a legacy otg device.
 224                  * Non-dt platform can set it afterwards.
 225                  */
 226                 otg_caps->otg_rev = 0;
 227         }
 228
 229         if (of_find_property(np, "hnp-disable", NULL))
 230                 otg_caps->hnp_support = false;
 231         if (of_find_property(np, "srp-disable", NULL))
 232                 otg_caps->srp_support = false;
 233         if (of_find_property(np, "adp-disable", NULL) ||
 234                                 (otg_caps->otg_rev < 0x0200))
 235                 otg_caps->adp_support = false;
 236
 237         return 0;
 238 }
 239 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
 240
 241 #endif
 242
 243 MODULE_LICENSE("GPL");