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