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#include <linux/debugfs.h>
  19#include "common.h"
  20
  21static const char *const ep_type_names[] = {
  22        [USB_ENDPOINT_XFER_CONTROL] = "ctrl",
  23        [USB_ENDPOINT_XFER_ISOC] = "isoc",
  24        [USB_ENDPOINT_XFER_BULK] = "bulk",
  25        [USB_ENDPOINT_XFER_INT] = "intr",
  26};
  27
  28const char *usb_ep_type_string(int ep_type)
  29{
  30        if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
  31                return "unknown";
  32
  33        return ep_type_names[ep_type];
  34}
  35EXPORT_SYMBOL_GPL(usb_ep_type_string);
  36
  37const char *usb_otg_state_string(enum usb_otg_state state)
  38{
  39        static const char *const names[] = {
  40                [OTG_STATE_A_IDLE] = "a_idle",
  41                [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
  42                [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
  43                [OTG_STATE_A_HOST] = "a_host",
  44                [OTG_STATE_A_SUSPEND] = "a_suspend",
  45                [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
  46                [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
  47                [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
  48                [OTG_STATE_B_IDLE] = "b_idle",
  49                [OTG_STATE_B_SRP_INIT] = "b_srp_init",
  50                [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
  51                [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
  52                [OTG_STATE_B_HOST] = "b_host",
  53        };
  54
  55        if (state < 0 || state >= ARRAY_SIZE(names))
  56                return "UNDEFINED";
  57
  58        return names[state];
  59}
  60EXPORT_SYMBOL_GPL(usb_otg_state_string);
  61
  62static const char *const speed_names[] = {
  63        [USB_SPEED_UNKNOWN] = "UNKNOWN",
  64        [USB_SPEED_LOW] = "low-speed",
  65        [USB_SPEED_FULL] = "full-speed",
  66        [USB_SPEED_HIGH] = "high-speed",
  67        [USB_SPEED_WIRELESS] = "wireless",
  68        [USB_SPEED_SUPER] = "super-speed",
  69        [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
  70};
  71
  72static const char *const ssp_rate[] = {
  73        [USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
  74        [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
  75        [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
  76        [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
  77};
  78
  79const char *usb_speed_string(enum usb_device_speed speed)
  80{
  81        if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
  82                speed = USB_SPEED_UNKNOWN;
  83        return speed_names[speed];
  84}
  85EXPORT_SYMBOL_GPL(usb_speed_string);
  86
  87enum usb_device_speed usb_get_maximum_speed(struct device *dev)
  88{
  89        const char *maximum_speed;
  90        int ret;
  91
  92        ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
  93        if (ret < 0)
  94                return USB_SPEED_UNKNOWN;
  95
  96        ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
  97        if (ret > 0)
  98                return USB_SPEED_SUPER_PLUS;
  99
 100        ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
 101        return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
 102}
 103EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
 104
 105enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
 106{
 107        const char *maximum_speed;
 108        int ret;
 109
 110        ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
 111        if (ret < 0)
 112                return USB_SSP_GEN_UNKNOWN;
 113
 114        ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
 115        return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
 116}
 117EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
 118
 119const char *usb_state_string(enum usb_device_state state)
 120{
 121        static const char *const names[] = {
 122                [USB_STATE_NOTATTACHED] = "not attached",
 123                [USB_STATE_ATTACHED] = "attached",
 124                [USB_STATE_POWERED] = "powered",
 125                [USB_STATE_RECONNECTING] = "reconnecting",
 126                [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
 127                [USB_STATE_DEFAULT] = "default",
 128                [USB_STATE_ADDRESS] = "addressed",
 129                [USB_STATE_CONFIGURED] = "configured",
 130                [USB_STATE_SUSPENDED] = "suspended",
 131        };
 132
 133        if (state < 0 || state >= ARRAY_SIZE(names))
 134                return "UNKNOWN";
 135
 136        return names[state];
 137}
 138EXPORT_SYMBOL_GPL(usb_state_string);
 139
 140static const char *const usb_dr_modes[] = {
 141        [USB_DR_MODE_UNKNOWN]           = "",
 142        [USB_DR_MODE_HOST]              = "host",
 143        [USB_DR_MODE_PERIPHERAL]        = "peripheral",
 144        [USB_DR_MODE_OTG]               = "otg",
 145};
 146
 147static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
 148{
 149        int ret;
 150
 151        ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
 152        return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
 153}
 154
 155enum usb_dr_mode usb_get_dr_mode(struct device *dev)
 156{
 157        const char *dr_mode;
 158        int err;
 159
 160        err = device_property_read_string(dev, "dr_mode", &dr_mode);
 161        if (err < 0)
 162                return USB_DR_MODE_UNKNOWN;
 163
 164        return usb_get_dr_mode_from_string(dr_mode);
 165}
 166EXPORT_SYMBOL_GPL(usb_get_dr_mode);
 167
 168#ifdef CONFIG_OF
 169/**
 170 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
 171 * which is associated with the given phy device_node
 172 * @np: Pointer to the given phy device_node
 173 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
 174 *        phys which do not have phy-cells
 175 *
 176 * In dts a usb controller associates with phy devices.  The function gets
 177 * the string from property 'dr_mode' of the controller associated with the
 178 * given phy device node, and returns the correspondig enum usb_dr_mode.
 179 */
 180enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
 181{
 182        struct device_node *controller = NULL;
 183        struct of_phandle_args args;
 184        const char *dr_mode;
 185        int index;
 186        int err;
 187
 188        do {
 189                controller = of_find_node_with_property(controller, "phys");
 190                if (!of_device_is_available(controller))
 191                        continue;
 192                index = 0;
 193                do {
 194                        if (arg0 == -1) {
 195                                args.np = of_parse_phandle(controller, "phys",
 196                                                        index);
 197                                args.args_count = 0;
 198                        } else {
 199                                err = of_parse_phandle_with_args(controller,
 200                                                        "phys", "#phy-cells",
 201                                                        index, &args);
 202                                if (err)
 203                                        break;
 204                        }
 205
 206                        of_node_put(args.np);
 207                        if (args.np == np && (args.args_count == 0 ||
 208                                              args.args[0] == arg0))
 209                                goto finish;
 210                        index++;
 211                } while (args.np);
 212        } while (controller);
 213
 214finish:
 215        err = of_property_read_string(controller, "dr_mode", &dr_mode);
 216        of_node_put(controller);
 217
 218        if (err < 0)
 219                return USB_DR_MODE_UNKNOWN;
 220
 221        return usb_get_dr_mode_from_string(dr_mode);
 222}
 223EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
 224
 225/**
 226 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 227 * for given targeted hosts (non-PC hosts)
 228 * @np: Pointer to the given device_node
 229 *
 230 * The function gets if the targeted hosts support TPL or not
 231 */
 232bool of_usb_host_tpl_support(struct device_node *np)
 233{
 234        return of_property_read_bool(np, "tpl-support");
 235}
 236EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 237
 238/**
 239 * of_usb_update_otg_caps - to update usb otg capabilities according to
 240 * the passed properties in DT.
 241 * @np: Pointer to the given device_node
 242 * @otg_caps: Pointer to the target usb_otg_caps to be set
 243 *
 244 * The function updates the otg capabilities
 245 */
 246int of_usb_update_otg_caps(struct device_node *np,
 247                        struct usb_otg_caps *otg_caps)
 248{
 249        u32 otg_rev;
 250
 251        if (!otg_caps)
 252                return -EINVAL;
 253
 254        if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
 255                switch (otg_rev) {
 256                case 0x0100:
 257                case 0x0120:
 258                case 0x0130:
 259                case 0x0200:
 260                        /* Choose the lesser one if it's already been set */
 261                        if (otg_caps->otg_rev)
 262                                otg_caps->otg_rev = min_t(u16, otg_rev,
 263                                                        otg_caps->otg_rev);
 264                        else
 265                                otg_caps->otg_rev = otg_rev;
 266                        break;
 267                default:
 268                        pr_err("%pOF: unsupported otg-rev: 0x%x\n",
 269                                                np, otg_rev);
 270                        return -EINVAL;
 271                }
 272        } else {
 273                /*
 274                 * otg-rev is mandatory for otg properties, if not passed
 275                 * we set it to be 0 and assume it's a legacy otg device.
 276                 * Non-dt platform can set it afterwards.
 277                 */
 278                otg_caps->otg_rev = 0;
 279        }
 280
 281        if (of_property_read_bool(np, "hnp-disable"))
 282                otg_caps->hnp_support = false;
 283        if (of_property_read_bool(np, "srp-disable"))
 284                otg_caps->srp_support = false;
 285        if (of_property_read_bool(np, "adp-disable") ||
 286                                (otg_caps->otg_rev < 0x0200))
 287                otg_caps->adp_support = false;
 288
 289        return 0;
 290}
 291EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
 292
 293/**
 294 * usb_of_get_companion_dev - Find the companion device
 295 * @dev: the device pointer to find a companion
 296 *
 297 * Find the companion device from platform bus.
 298 *
 299 * Takes a reference to the returned struct device which needs to be dropped
 300 * after use.
 301 *
 302 * Return: On success, a pointer to the companion device, %NULL on failure.
 303 */
 304struct device *usb_of_get_companion_dev(struct device *dev)
 305{
 306        struct device_node *node;
 307        struct platform_device *pdev = NULL;
 308
 309        node = of_parse_phandle(dev->of_node, "companion", 0);
 310        if (node)
 311                pdev = of_find_device_by_node(node);
 312
 313        of_node_put(node);
 314
 315        return pdev ? &pdev->dev : NULL;
 316}
 317EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
 318#endif
 319
 320struct dentry *usb_debug_root;
 321EXPORT_SYMBOL_GPL(usb_debug_root);
 322
 323static int __init usb_common_init(void)
 324{
 325        usb_debug_root = debugfs_create_dir("usb", NULL);
 326        ledtrig_usb_init();
 327        return 0;
 328}
 329
 330static void __exit usb_common_exit(void)
 331{
 332        ledtrig_usb_exit();
 333        debugfs_remove_recursive(usb_debug_root);
 334}
 335
 336subsys_initcall(usb_common_init);
 337module_exit(usb_common_exit);
 338
 339MODULE_LICENSE("GPL");
 340