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