kernel/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
  21 const char *usb_otg_state_string(enum usb_otg_state state)
  22 {
  23         static const char *const names[] = {
  24                 [OTG_STATE_A_IDLE] = "a_idle",
  25                 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
  26                 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
  27                 [OTG_STATE_A_HOST] = "a_host",
  28                 [OTG_STATE_A_SUSPEND] = "a_suspend",
  29                 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
  30                 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
  31                 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
  32                 [OTG_STATE_B_IDLE] = "b_idle",
  33                 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
  34                 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
  35                 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
  36                 [OTG_STATE_B_HOST] = "b_host",
  37         };
  38
  39         if (state < 0 || state >= ARRAY_SIZE(names))
  40                 return "UNDEFINED";
  41
  42         return names[state];
  43 }
  44 EXPORT_SYMBOL_GPL(usb_otg_state_string);
  45
  46 static const char *const speed_names[] = {
  47         [USB_SPEED_UNKNOWN] = "UNKNOWN",
  48         [USB_SPEED_LOW] = "low-speed",
  49         [USB_SPEED_FULL] = "full-speed",
  50         [USB_SPEED_HIGH] = "high-speed",
  51         [USB_SPEED_WIRELESS] = "wireless",
  52         [USB_SPEED_SUPER] = "super-speed",
  53 };
  54
  55 const char *usb_speed_string(enum usb_device_speed speed)
  56 {
  57         if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
  58                 speed = USB_SPEED_UNKNOWN;
  59         return speed_names[speed];
  60 }
  61 EXPORT_SYMBOL_GPL(usb_speed_string);
  62
  63 const char *usb_state_string(enum usb_device_state state)
  64 {
  65         static const char *const names[] = {
  66                 [USB_STATE_NOTATTACHED] = "not attached",
  67                 [USB_STATE_ATTACHED] = "attached",
  68                 [USB_STATE_POWERED] = "powered",
  69                 [USB_STATE_RECONNECTING] = "reconnecting",
  70                 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
  71                 [USB_STATE_DEFAULT] = "default",
  72                 [USB_STATE_ADDRESS] = "addressed",
  73                 [USB_STATE_CONFIGURED] = "configured",
  74                 [USB_STATE_SUSPENDED] = "suspended",
  75         };
  76
  77         if (state < 0 || state >= ARRAY_SIZE(names))
  78                 return "UNKNOWN";
  79
  80         return names[state];
  81 }
  82 EXPORT_SYMBOL_GPL(usb_state_string);
  83
  84 #ifdef CONFIG_OF
  85 static const char *const usb_dr_modes[] = {
  86         [USB_DR_MODE_UNKNOWN]           = "",
  87         [USB_DR_MODE_HOST]              = "host",
  88         [USB_DR_MODE_PERIPHERAL]        = "peripheral",
  89         [USB_DR_MODE_OTG]               = "otg",
  90 };
  91
  92 /**
  93  * of_usb_get_dr_mode - Get dual role mode for given device_node
  94  * @np: Pointer to the given device_node
  95  *
  96  * The function gets phy interface string from property 'dr_mode',
  97  * and returns the correspondig enum usb_dr_mode
  98  */
  99 enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
 100 {
 101         const char *dr_mode;
 102         int err, i;
 103
 104         err = of_property_read_string(np, "dr_mode", &dr_mode);
 105         if (err < 0)
 106                 return USB_DR_MODE_UNKNOWN;
 107
 108         for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
 109                 if (!strcmp(dr_mode, usb_dr_modes[i]))
 110                         return i;
 111
 112         return USB_DR_MODE_UNKNOWN;
 113 }
 114 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode);
 115
 116 /**
 117  * of_usb_get_maximum_speed - Get maximum requested speed for a given USB
 118  * controller.
 119  * @np: Pointer to the given device_node
 120  *
 121  * The function gets the maximum speed string from property "maximum-speed",
 122  * and returns the corresponding enum usb_device_speed.
 123  */
 124 enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np)
 125 {
 126         const char *maximum_speed;
 127         int err;
 128         int i;
 129
 130         err = of_property_read_string(np, "maximum-speed", &maximum_speed);
 131         if (err < 0)
 132                 return USB_SPEED_UNKNOWN;
 133
 134         for (i = 0; i < ARRAY_SIZE(speed_names); i++)
 135                 if (strcmp(maximum_speed, speed_names[i]) == 0)
 136                         return i;
 137
 138         return USB_SPEED_UNKNOWN;
 139 }
 140 EXPORT_SYMBOL_GPL(of_usb_get_maximum_speed);
 141
 142 /**
 143  * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 144  * for given targeted hosts (non-PC hosts)
 145  * @np: Pointer to the given device_node
 146  *
 147  * The function gets if the targeted hosts support TPL or not
 148  */
 149 bool of_usb_host_tpl_support(struct device_node *np)
 150 {
 151         if (of_find_property(np, "tpl-support", NULL))
 152                 return true;
 153
 154         return false;
 155 }
 156 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 157 #endif
 158
 159 MODULE_LICENSE("GPL");