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 };
  55
  56 const char *usb_speed_string(enum usb_device_speed speed)
  57 {
  58         if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
  59                 speed = USB_SPEED_UNKNOWN;
  60         return speed_names[speed];
  61 }
  62 EXPORT_SYMBOL_GPL(usb_speed_string);
  63
  64 enum usb_device_speed usb_get_maximum_speed(struct device *dev)
  65 {
  66         const char *maximum_speed;
  67         int ret;
  68
  69         ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
  70         if (ret < 0)
  71                 return USB_SPEED_UNKNOWN;
  72
  73         ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
  74
  75         return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
  76 }
  77 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
  78
  79 const char *usb_state_string(enum usb_device_state state)
  80 {
  81         static const char *const names[] = {
  82                 [USB_STATE_NOTATTACHED] = "not attached",
  83                 [USB_STATE_ATTACHED] = "attached",
  84                 [USB_STATE_POWERED] = "powered",
  85                 [USB_STATE_RECONNECTING] = "reconnecting",
  86                 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
  87                 [USB_STATE_DEFAULT] = "default",
  88                 [USB_STATE_ADDRESS] = "addressed",
  89                 [USB_STATE_CONFIGURED] = "configured",
  90                 [USB_STATE_SUSPENDED] = "suspended",
  91         };
  92
  93         if (state < 0 || state >= ARRAY_SIZE(names))
  94                 return "UNKNOWN";
  95
  96         return names[state];
  97 }
  98 EXPORT_SYMBOL_GPL(usb_state_string);
  99
 100 static const char *const usb_dr_modes[] = {
 101         [USB_DR_MODE_UNKNOWN]           = "",
 102         [USB_DR_MODE_HOST]              = "host",
 103         [USB_DR_MODE_PERIPHERAL]        = "peripheral",
 104         [USB_DR_MODE_OTG]               = "otg",
 105 };
 106
 107 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
 108 {
 109         int ret;
 110
 111         ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
 112         return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
 113 }
 114
 115 enum usb_dr_mode usb_get_dr_mode(struct device *dev)
 116 {
 117         const char *dr_mode;
 118         int err;
 119
 120         err = device_property_read_string(dev, "dr_mode", &dr_mode);
 121         if (err < 0)
 122                 return USB_DR_MODE_UNKNOWN;
 123
 124         return usb_get_dr_mode_from_string(dr_mode);
 125 }
 126 EXPORT_SYMBOL_GPL(usb_get_dr_mode);
 127
 128 #ifdef CONFIG_OF
 129 /**
 130  * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
 131  * which is associated with the given phy device_node
 132  * @np: Pointer to the given phy device_node
 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 *phy_np)
 139 {
 140         struct device_node *controller = NULL;
 141         struct device_node *phy;
 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                         phy = of_parse_phandle(controller, "phys", index);
 151                         of_node_put(phy);
 152                         if (phy == phy_np)
 153                                 goto finish;
 154                         index++;
 155                 } while (phy);
 156         } while (controller);
 157
 158 finish:
 159         err = of_property_read_string(controller, "dr_mode", &dr_mode);
 160         of_node_put(controller);
 161
 162         if (err < 0)
 163                 return USB_DR_MODE_UNKNOWN;
 164
 165         return usb_get_dr_mode_from_string(dr_mode);
 166 }
 167 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
 168
 169 /**
 170  * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 171  * for given targeted hosts (non-PC hosts)
 172  * @np: Pointer to the given device_node
 173  *
 174  * The function gets if the targeted hosts support TPL or not
 175  */
 176 bool of_usb_host_tpl_support(struct device_node *np)
 177 {
 178         if (of_find_property(np, "tpl-support", NULL))
 179                 return true;
 180
 181         return false;
 182 }
 183 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 184
 185 /**
 186  * of_usb_update_otg_caps - to update usb otg capabilities according to
 187  * the passed properties in DT.
 188  * @np: Pointer to the given device_node
 189  * @otg_caps: Pointer to the target usb_otg_caps to be set
 190  *
 191  * The function updates the otg capabilities
 192  */
 193 int of_usb_update_otg_caps(struct device_node *np,
 194                         struct usb_otg_caps *otg_caps)
 195 {
 196         u32 otg_rev;
 197
 198         if (!otg_caps)
 199                 return -EINVAL;
 200
 201         if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
 202                 switch (otg_rev) {
 203                 case 0x0100:
 204                 case 0x0120:
 205                 case 0x0130:
 206                 case 0x0200:
 207                         /* Choose the lesser one if it's already been set */
 208                         if (otg_caps->otg_rev)
 209                                 otg_caps->otg_rev = min_t(u16, otg_rev,
 210                                                         otg_caps->otg_rev);
 211                         else
 212                                 otg_caps->otg_rev = otg_rev;
 213                         break;
 214                 default:
 215                         pr_err("%s: unsupported otg-rev: 0x%x\n",
 216                                                 np->full_name, otg_rev);
 217                         return -EINVAL;
 218                 }
 219         } else {
 220                 /*
 221                  * otg-rev is mandatory for otg properties, if not passed
 222                  * we set it to be 0 and assume it's a legacy otg device.
 223                  * Non-dt platform can set it afterwards.
 224                  */
 225                 otg_caps->otg_rev = 0;
 226         }
 227
 228         if (of_find_property(np, "hnp-disable", NULL))
 229                 otg_caps->hnp_support = false;
 230         if (of_find_property(np, "srp-disable", NULL))
 231                 otg_caps->srp_support = false;
 232         if (of_find_property(np, "adp-disable", NULL) ||
 233                                 (otg_caps->otg_rev < 0x0200))
 234                 otg_caps->adp_support = false;
 235
 236         return 0;
 237 }
 238 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
 239
 240 #endif
 241
 242 MODULE_LICENSE("GPL");