linux/drivers/usb/phy/phy.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * phy.c -- USB phy handling
   4 *
   5 * Copyright (C) 2004-2013 Texas Instruments
   6 */
   7#include <linux/kernel.h>
   8#include <linux/export.h>
   9#include <linux/err.h>
  10#include <linux/device.h>
  11#include <linux/module.h>
  12#include <linux/slab.h>
  13#include <linux/of.h>
  14
  15#include <linux/usb/phy.h>
  16
  17/* Default current range by charger type. */
  18#define DEFAULT_SDP_CUR_MIN     2
  19#define DEFAULT_SDP_CUR_MAX     500
  20#define DEFAULT_SDP_CUR_MIN_SS  150
  21#define DEFAULT_SDP_CUR_MAX_SS  900
  22#define DEFAULT_DCP_CUR_MIN     500
  23#define DEFAULT_DCP_CUR_MAX     5000
  24#define DEFAULT_CDP_CUR_MIN     1500
  25#define DEFAULT_CDP_CUR_MAX     5000
  26#define DEFAULT_ACA_CUR_MIN     1500
  27#define DEFAULT_ACA_CUR_MAX     5000
  28
  29static LIST_HEAD(phy_list);
  30static DEFINE_SPINLOCK(phy_lock);
  31
  32struct phy_devm {
  33        struct usb_phy *phy;
  34        struct notifier_block *nb;
  35};
  36
  37static const char *const usb_chger_type[] = {
  38        [UNKNOWN_TYPE]                  = "USB_CHARGER_UNKNOWN_TYPE",
  39        [SDP_TYPE]                      = "USB_CHARGER_SDP_TYPE",
  40        [CDP_TYPE]                      = "USB_CHARGER_CDP_TYPE",
  41        [DCP_TYPE]                      = "USB_CHARGER_DCP_TYPE",
  42        [ACA_TYPE]                      = "USB_CHARGER_ACA_TYPE",
  43};
  44
  45static const char *const usb_chger_state[] = {
  46        [USB_CHARGER_DEFAULT]   = "USB_CHARGER_DEFAULT",
  47        [USB_CHARGER_PRESENT]   = "USB_CHARGER_PRESENT",
  48        [USB_CHARGER_ABSENT]    = "USB_CHARGER_ABSENT",
  49};
  50
  51static struct usb_phy *__usb_find_phy(struct list_head *list,
  52        enum usb_phy_type type)
  53{
  54        struct usb_phy  *phy = NULL;
  55
  56        list_for_each_entry(phy, list, head) {
  57                if (phy->type != type)
  58                        continue;
  59
  60                return phy;
  61        }
  62
  63        return ERR_PTR(-ENODEV);
  64}
  65
  66static struct usb_phy *__of_usb_find_phy(struct device_node *node)
  67{
  68        struct usb_phy  *phy;
  69
  70        if (!of_device_is_available(node))
  71                return ERR_PTR(-ENODEV);
  72
  73        list_for_each_entry(phy, &phy_list, head) {
  74                if (node != phy->dev->of_node)
  75                        continue;
  76
  77                return phy;
  78        }
  79
  80        return ERR_PTR(-EPROBE_DEFER);
  81}
  82
  83static struct usb_phy *__device_to_usb_phy(struct device *dev)
  84{
  85        struct usb_phy *usb_phy;
  86
  87        list_for_each_entry(usb_phy, &phy_list, head) {
  88                if (usb_phy->dev == dev)
  89                        return usb_phy;
  90        }
  91
  92        return NULL;
  93}
  94
  95static void usb_phy_set_default_current(struct usb_phy *usb_phy)
  96{
  97        usb_phy->chg_cur.sdp_min = DEFAULT_SDP_CUR_MIN;
  98        usb_phy->chg_cur.sdp_max = DEFAULT_SDP_CUR_MAX;
  99        usb_phy->chg_cur.dcp_min = DEFAULT_DCP_CUR_MIN;
 100        usb_phy->chg_cur.dcp_max = DEFAULT_DCP_CUR_MAX;
 101        usb_phy->chg_cur.cdp_min = DEFAULT_CDP_CUR_MIN;
 102        usb_phy->chg_cur.cdp_max = DEFAULT_CDP_CUR_MAX;
 103        usb_phy->chg_cur.aca_min = DEFAULT_ACA_CUR_MIN;
 104        usb_phy->chg_cur.aca_max = DEFAULT_ACA_CUR_MAX;
 105}
 106
 107/**
 108 * usb_phy_notify_charger_work - notify the USB charger state
 109 * @work: the charger work to notify the USB charger state
 110 *
 111 * This work can be issued when USB charger state has been changed or
 112 * USB charger current has been changed, then we can notify the current
 113 * what can be drawn to power user and the charger state to userspace.
 114 *
 115 * If we get the charger type from extcon subsystem, we can notify the
 116 * charger state to power user automatically by usb_phy_get_charger_type()
 117 * issuing from extcon subsystem.
 118 *
 119 * If we get the charger type from ->charger_detect() instead of extcon
 120 * subsystem, the usb phy driver should issue usb_phy_set_charger_state()
 121 * to set charger state when the charger state has been changed.
 122 */
 123static void usb_phy_notify_charger_work(struct work_struct *work)
 124{
 125        struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work);
 126        unsigned int min, max;
 127
 128        switch (usb_phy->chg_state) {
 129        case USB_CHARGER_PRESENT:
 130                usb_phy_get_charger_current(usb_phy, &min, &max);
 131
 132                atomic_notifier_call_chain(&usb_phy->notifier, max, usb_phy);
 133                break;
 134        case USB_CHARGER_ABSENT:
 135                usb_phy_set_default_current(usb_phy);
 136
 137                atomic_notifier_call_chain(&usb_phy->notifier, 0, usb_phy);
 138                break;
 139        default:
 140                dev_warn(usb_phy->dev, "Unknown USB charger state: %d\n",
 141                         usb_phy->chg_state);
 142                return;
 143        }
 144
 145        kobject_uevent(&usb_phy->dev->kobj, KOBJ_CHANGE);
 146}
 147
 148static int usb_phy_uevent(struct device *dev, struct kobj_uevent_env *env)
 149{
 150        struct usb_phy *usb_phy;
 151        char uchger_state[50] = { 0 };
 152        char uchger_type[50] = { 0 };
 153        unsigned long flags;
 154
 155        spin_lock_irqsave(&phy_lock, flags);
 156        usb_phy = __device_to_usb_phy(dev);
 157        spin_unlock_irqrestore(&phy_lock, flags);
 158
 159        if (!usb_phy)
 160                return -ENODEV;
 161
 162        snprintf(uchger_state, ARRAY_SIZE(uchger_state),
 163                 "USB_CHARGER_STATE=%s", usb_chger_state[usb_phy->chg_state]);
 164
 165        snprintf(uchger_type, ARRAY_SIZE(uchger_type),
 166                 "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]);
 167
 168        if (add_uevent_var(env, uchger_state))
 169                return -ENOMEM;
 170
 171        if (add_uevent_var(env, uchger_type))
 172                return -ENOMEM;
 173
 174        return 0;
 175}
 176
 177static void __usb_phy_get_charger_type(struct usb_phy *usb_phy)
 178{
 179        if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_SDP) > 0) {
 180                usb_phy->chg_type = SDP_TYPE;
 181                usb_phy->chg_state = USB_CHARGER_PRESENT;
 182        } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_CDP) > 0) {
 183                usb_phy->chg_type = CDP_TYPE;
 184                usb_phy->chg_state = USB_CHARGER_PRESENT;
 185        } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_DCP) > 0) {
 186                usb_phy->chg_type = DCP_TYPE;
 187                usb_phy->chg_state = USB_CHARGER_PRESENT;
 188        } else if (extcon_get_state(usb_phy->edev, EXTCON_CHG_USB_ACA) > 0) {
 189                usb_phy->chg_type = ACA_TYPE;
 190                usb_phy->chg_state = USB_CHARGER_PRESENT;
 191        } else {
 192                usb_phy->chg_type = UNKNOWN_TYPE;
 193                usb_phy->chg_state = USB_CHARGER_ABSENT;
 194        }
 195
 196        schedule_work(&usb_phy->chg_work);
 197}
 198
 199/**
 200 * usb_phy_get_charger_type - get charger type from extcon subsystem
 201 * @nb: the notifier block to determine charger type
 202 * @state: the cable state
 203 * @data: private data
 204 *
 205 * Determin the charger type from extcon subsystem which also means the
 206 * charger state has been chaned, then we should notify this event.
 207 */
 208static int usb_phy_get_charger_type(struct notifier_block *nb,
 209                                    unsigned long state, void *data)
 210{
 211        struct usb_phy *usb_phy = container_of(nb, struct usb_phy, type_nb);
 212
 213        __usb_phy_get_charger_type(usb_phy);
 214        return NOTIFY_OK;
 215}
 216
 217/**
 218 * usb_phy_set_charger_current - set the USB charger current
 219 * @usb_phy: the USB phy to be used
 220 * @mA: the current need to be set
 221 *
 222 * Usually we only change the charger default current when USB finished the
 223 * enumeration as one SDP charger. As one SDP charger, usb_phy_set_power()
 224 * will issue this function to change charger current when after setting USB
 225 * configuration, or suspend/resume USB. For other type charger, we should
 226 * use the default charger current and we do not suggest to issue this function
 227 * to change the charger current.
 228 *
 229 * When USB charger current has been changed, we need to notify the power users.
 230 */
 231void usb_phy_set_charger_current(struct usb_phy *usb_phy, unsigned int mA)
 232{
 233        switch (usb_phy->chg_type) {
 234        case SDP_TYPE:
 235                if (usb_phy->chg_cur.sdp_max == mA)
 236                        return;
 237
 238                usb_phy->chg_cur.sdp_max = (mA > DEFAULT_SDP_CUR_MAX_SS) ?
 239                        DEFAULT_SDP_CUR_MAX_SS : mA;
 240                break;
 241        case DCP_TYPE:
 242                if (usb_phy->chg_cur.dcp_max == mA)
 243                        return;
 244
 245                usb_phy->chg_cur.dcp_max = (mA > DEFAULT_DCP_CUR_MAX) ?
 246                        DEFAULT_DCP_CUR_MAX : mA;
 247                break;
 248        case CDP_TYPE:
 249                if (usb_phy->chg_cur.cdp_max == mA)
 250                        return;
 251
 252                usb_phy->chg_cur.cdp_max = (mA > DEFAULT_CDP_CUR_MAX) ?
 253                        DEFAULT_CDP_CUR_MAX : mA;
 254                break;
 255        case ACA_TYPE:
 256                if (usb_phy->chg_cur.aca_max == mA)
 257                        return;
 258
 259                usb_phy->chg_cur.aca_max = (mA > DEFAULT_ACA_CUR_MAX) ?
 260                        DEFAULT_ACA_CUR_MAX : mA;
 261                break;
 262        default:
 263                return;
 264        }
 265
 266        schedule_work(&usb_phy->chg_work);
 267}
 268EXPORT_SYMBOL_GPL(usb_phy_set_charger_current);
 269
 270/**
 271 * usb_phy_get_charger_current - get the USB charger current
 272 * @usb_phy: the USB phy to be used
 273 * @min: the minimum current
 274 * @max: the maximum current
 275 *
 276 * Usually we will notify the maximum current to power user, but for some
 277 * special case, power user also need the minimum current value. Then the
 278 * power user can issue this function to get the suitable current.
 279 */
 280void usb_phy_get_charger_current(struct usb_phy *usb_phy,
 281                                 unsigned int *min, unsigned int *max)
 282{
 283        switch (usb_phy->chg_type) {
 284        case SDP_TYPE:
 285                *min = usb_phy->chg_cur.sdp_min;
 286                *max = usb_phy->chg_cur.sdp_max;
 287                break;
 288        case DCP_TYPE:
 289                *min = usb_phy->chg_cur.dcp_min;
 290                *max = usb_phy->chg_cur.dcp_max;
 291                break;
 292        case CDP_TYPE:
 293                *min = usb_phy->chg_cur.cdp_min;
 294                *max = usb_phy->chg_cur.cdp_max;
 295                break;
 296        case ACA_TYPE:
 297                *min = usb_phy->chg_cur.aca_min;
 298                *max = usb_phy->chg_cur.aca_max;
 299                break;
 300        default:
 301                *min = 0;
 302                *max = 0;
 303                break;
 304        }
 305}
 306EXPORT_SYMBOL_GPL(usb_phy_get_charger_current);
 307
 308/**
 309 * usb_phy_set_charger_state - set the USB charger state
 310 * @usb_phy: the USB phy to be used
 311 * @state: the new state need to be set for charger
 312 *
 313 * The usb phy driver can issue this function when the usb phy driver
 314 * detected the charger state has been changed, in this case the charger
 315 * type should be get from ->charger_detect().
 316 */
 317void usb_phy_set_charger_state(struct usb_phy *usb_phy,
 318                               enum usb_charger_state state)
 319{
 320        if (usb_phy->chg_state == state || !usb_phy->charger_detect)
 321                return;
 322
 323        usb_phy->chg_state = state;
 324        if (usb_phy->chg_state == USB_CHARGER_PRESENT)
 325                usb_phy->chg_type = usb_phy->charger_detect(usb_phy);
 326        else
 327                usb_phy->chg_type = UNKNOWN_TYPE;
 328
 329        schedule_work(&usb_phy->chg_work);
 330}
 331EXPORT_SYMBOL_GPL(usb_phy_set_charger_state);
 332
 333static void devm_usb_phy_release(struct device *dev, void *res)
 334{
 335        struct usb_phy *phy = *(struct usb_phy **)res;
 336
 337        usb_put_phy(phy);
 338}
 339
 340static void devm_usb_phy_release2(struct device *dev, void *_res)
 341{
 342        struct phy_devm *res = _res;
 343
 344        if (res->nb)
 345                usb_unregister_notifier(res->phy, res->nb);
 346        usb_put_phy(res->phy);
 347}
 348
 349static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
 350{
 351        struct usb_phy **phy = res;
 352
 353        return *phy == match_data;
 354}
 355
 356static void usb_charger_init(struct usb_phy *usb_phy)
 357{
 358        usb_phy->chg_type = UNKNOWN_TYPE;
 359        usb_phy->chg_state = USB_CHARGER_DEFAULT;
 360        usb_phy_set_default_current(usb_phy);
 361        INIT_WORK(&usb_phy->chg_work, usb_phy_notify_charger_work);
 362}
 363
 364static int usb_add_extcon(struct usb_phy *x)
 365{
 366        int ret;
 367
 368        if (of_property_read_bool(x->dev->of_node, "extcon")) {
 369                x->edev = extcon_get_edev_by_phandle(x->dev, 0);
 370                if (IS_ERR(x->edev))
 371                        return PTR_ERR(x->edev);
 372
 373                x->id_edev = extcon_get_edev_by_phandle(x->dev, 1);
 374                if (IS_ERR(x->id_edev)) {
 375                        x->id_edev = NULL;
 376                        dev_info(x->dev, "No separate ID extcon device\n");
 377                }
 378
 379                if (x->vbus_nb.notifier_call) {
 380                        ret = devm_extcon_register_notifier(x->dev, x->edev,
 381                                                            EXTCON_USB,
 382                                                            &x->vbus_nb);
 383                        if (ret < 0) {
 384                                dev_err(x->dev,
 385                                        "register VBUS notifier failed\n");
 386                                return ret;
 387                        }
 388                } else {
 389                        x->type_nb.notifier_call = usb_phy_get_charger_type;
 390
 391                        ret = devm_extcon_register_notifier(x->dev, x->edev,
 392                                                            EXTCON_CHG_USB_SDP,
 393                                                            &x->type_nb);
 394                        if (ret) {
 395                                dev_err(x->dev,
 396                                        "register extcon USB SDP failed.\n");
 397                                return ret;
 398                        }
 399
 400                        ret = devm_extcon_register_notifier(x->dev, x->edev,
 401                                                            EXTCON_CHG_USB_CDP,
 402                                                            &x->type_nb);
 403                        if (ret) {
 404                                dev_err(x->dev,
 405                                        "register extcon USB CDP failed.\n");
 406                                return ret;
 407                        }
 408
 409                        ret = devm_extcon_register_notifier(x->dev, x->edev,
 410                                                            EXTCON_CHG_USB_DCP,
 411                                                            &x->type_nb);
 412                        if (ret) {
 413                                dev_err(x->dev,
 414                                        "register extcon USB DCP failed.\n");
 415                                return ret;
 416                        }
 417
 418                        ret = devm_extcon_register_notifier(x->dev, x->edev,
 419                                                            EXTCON_CHG_USB_ACA,
 420                                                            &x->type_nb);
 421                        if (ret) {
 422                                dev_err(x->dev,
 423                                        "register extcon USB ACA failed.\n");
 424                                return ret;
 425                        }
 426                }
 427
 428                if (x->id_nb.notifier_call) {
 429                        struct extcon_dev *id_ext;
 430
 431                        if (x->id_edev)
 432                                id_ext = x->id_edev;
 433                        else
 434                                id_ext = x->edev;
 435
 436                        ret = devm_extcon_register_notifier(x->dev, id_ext,
 437                                                            EXTCON_USB_HOST,
 438                                                            &x->id_nb);
 439                        if (ret < 0) {
 440                                dev_err(x->dev,
 441                                        "register ID notifier failed\n");
 442                                return ret;
 443                        }
 444                }
 445        }
 446
 447        if (x->type_nb.notifier_call)
 448                __usb_phy_get_charger_type(x);
 449
 450        return 0;
 451}
 452
 453/**
 454 * devm_usb_get_phy - find the USB PHY
 455 * @dev: device that requests this phy
 456 * @type: the type of the phy the controller requires
 457 *
 458 * Gets the phy using usb_get_phy(), and associates a device with it using
 459 * devres. On driver detach, release function is invoked on the devres data,
 460 * then, devres data is freed.
 461 *
 462 * For use by USB host and peripheral drivers.
 463 */
 464struct usb_phy *devm_usb_get_phy(struct device *dev, enum usb_phy_type type)
 465{
 466        struct usb_phy **ptr, *phy;
 467
 468        ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
 469        if (!ptr)
 470                return ERR_PTR(-ENOMEM);
 471
 472        phy = usb_get_phy(type);
 473        if (!IS_ERR(phy)) {
 474                *ptr = phy;
 475                devres_add(dev, ptr);
 476        } else
 477                devres_free(ptr);
 478
 479        return phy;
 480}
 481EXPORT_SYMBOL_GPL(devm_usb_get_phy);
 482
 483/**
 484 * usb_get_phy - find the USB PHY
 485 * @type: the type of the phy the controller requires
 486 *
 487 * Returns the phy driver, after getting a refcount to it; or
 488 * -ENODEV if there is no such phy.  The caller is responsible for
 489 * calling usb_put_phy() to release that count.
 490 *
 491 * For use by USB host and peripheral drivers.
 492 */
 493struct usb_phy *usb_get_phy(enum usb_phy_type type)
 494{
 495        struct usb_phy  *phy = NULL;
 496        unsigned long   flags;
 497
 498        spin_lock_irqsave(&phy_lock, flags);
 499
 500        phy = __usb_find_phy(&phy_list, type);
 501        if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
 502                pr_debug("PHY: unable to find transceiver of type %s\n",
 503                        usb_phy_type_string(type));
 504                if (!IS_ERR(phy))
 505                        phy = ERR_PTR(-ENODEV);
 506
 507                goto err0;
 508        }
 509
 510        get_device(phy->dev);
 511
 512err0:
 513        spin_unlock_irqrestore(&phy_lock, flags);
 514
 515        return phy;
 516}
 517EXPORT_SYMBOL_GPL(usb_get_phy);
 518
 519/**
 520 * devm_usb_get_phy_by_node - find the USB PHY by device_node
 521 * @dev: device that requests this phy
 522 * @node: the device_node for the phy device.
 523 * @nb: a notifier_block to register with the phy.
 524 *
 525 * Returns the phy driver associated with the given device_node,
 526 * after getting a refcount to it, -ENODEV if there is no such phy or
 527 * -EPROBE_DEFER if the device is not yet loaded. While at that, it
 528 * also associates the device with
 529 * the phy using devres. On driver detach, release function is invoked
 530 * on the devres data, then, devres data is freed.
 531 *
 532 * For use by peripheral drivers for devices related to a phy,
 533 * such as a charger.
 534 */
 535struct  usb_phy *devm_usb_get_phy_by_node(struct device *dev,
 536                                          struct device_node *node,
 537                                          struct notifier_block *nb)
 538{
 539        struct usb_phy  *phy = ERR_PTR(-ENOMEM);
 540        struct phy_devm *ptr;
 541        unsigned long   flags;
 542
 543        ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL);
 544        if (!ptr) {
 545                dev_dbg(dev, "failed to allocate memory for devres\n");
 546                goto err0;
 547        }
 548
 549        spin_lock_irqsave(&phy_lock, flags);
 550
 551        phy = __of_usb_find_phy(node);
 552        if (IS_ERR(phy)) {
 553                devres_free(ptr);
 554                goto err1;
 555        }
 556
 557        if (!try_module_get(phy->dev->driver->owner)) {
 558                phy = ERR_PTR(-ENODEV);
 559                devres_free(ptr);
 560                goto err1;
 561        }
 562        if (nb)
 563                usb_register_notifier(phy, nb);
 564        ptr->phy = phy;
 565        ptr->nb = nb;
 566        devres_add(dev, ptr);
 567
 568        get_device(phy->dev);
 569
 570err1:
 571        spin_unlock_irqrestore(&phy_lock, flags);
 572
 573err0:
 574
 575        return phy;
 576}
 577EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node);
 578
 579/**
 580 * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
 581 * @dev: device that requests this phy
 582 * @phandle: name of the property holding the phy phandle value
 583 * @index: the index of the phy
 584 *
 585 * Returns the phy driver associated with the given phandle value,
 586 * after getting a refcount to it, -ENODEV if there is no such phy or
 587 * -EPROBE_DEFER if there is a phandle to the phy, but the device is
 588 * not yet loaded. While at that, it also associates the device with
 589 * the phy using devres. On driver detach, release function is invoked
 590 * on the devres data, then, devres data is freed.
 591 *
 592 * For use by USB host and peripheral drivers.
 593 */
 594struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
 595        const char *phandle, u8 index)
 596{
 597        struct device_node *node;
 598        struct usb_phy  *phy;
 599
 600        if (!dev->of_node) {
 601                dev_dbg(dev, "device does not have a device node entry\n");
 602                return ERR_PTR(-EINVAL);
 603        }
 604
 605        node = of_parse_phandle(dev->of_node, phandle, index);
 606        if (!node) {
 607                dev_dbg(dev, "failed to get %s phandle in %pOF node\n", phandle,
 608                        dev->of_node);
 609                return ERR_PTR(-ENODEV);
 610        }
 611        phy = devm_usb_get_phy_by_node(dev, node, NULL);
 612        of_node_put(node);
 613        return phy;
 614}
 615EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);
 616
 617/**
 618 * devm_usb_put_phy - release the USB PHY
 619 * @dev: device that wants to release this phy
 620 * @phy: the phy returned by devm_usb_get_phy()
 621 *
 622 * destroys the devres associated with this phy and invokes usb_put_phy
 623 * to release the phy.
 624 *
 625 * For use by USB host and peripheral drivers.
 626 */
 627void devm_usb_put_phy(struct device *dev, struct usb_phy *phy)
 628{
 629        int r;
 630
 631        r = devres_destroy(dev, devm_usb_phy_release, devm_usb_phy_match, phy);
 632        dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
 633}
 634EXPORT_SYMBOL_GPL(devm_usb_put_phy);
 635
 636/**
 637 * usb_put_phy - release the USB PHY
 638 * @x: the phy returned by usb_get_phy()
 639 *
 640 * Releases a refcount the caller received from usb_get_phy().
 641 *
 642 * For use by USB host and peripheral drivers.
 643 */
 644void usb_put_phy(struct usb_phy *x)
 645{
 646        if (x) {
 647                struct module *owner = x->dev->driver->owner;
 648
 649                put_device(x->dev);
 650                module_put(owner);
 651        }
 652}
 653EXPORT_SYMBOL_GPL(usb_put_phy);
 654
 655/**
 656 * usb_add_phy: declare the USB PHY
 657 * @x: the USB phy to be used; or NULL
 658 * @type: the type of this PHY
 659 *
 660 * This call is exclusively for use by phy drivers, which
 661 * coordinate the activities of drivers for host and peripheral
 662 * controllers, and in some cases for VBUS current regulation.
 663 */
 664int usb_add_phy(struct usb_phy *x, enum usb_phy_type type)
 665{
 666        int             ret = 0;
 667        unsigned long   flags;
 668        struct usb_phy  *phy;
 669
 670        if (x->type != USB_PHY_TYPE_UNDEFINED) {
 671                dev_err(x->dev, "not accepting initialized PHY %s\n", x->label);
 672                return -EINVAL;
 673        }
 674
 675        usb_charger_init(x);
 676        ret = usb_add_extcon(x);
 677        if (ret)
 678                return ret;
 679
 680        ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
 681
 682        spin_lock_irqsave(&phy_lock, flags);
 683
 684        list_for_each_entry(phy, &phy_list, head) {
 685                if (phy->type == type) {
 686                        ret = -EBUSY;
 687                        dev_err(x->dev, "transceiver type %s already exists\n",
 688                                                usb_phy_type_string(type));
 689                        goto out;
 690                }
 691        }
 692
 693        x->type = type;
 694        list_add_tail(&x->head, &phy_list);
 695
 696out:
 697        spin_unlock_irqrestore(&phy_lock, flags);
 698        return ret;
 699}
 700EXPORT_SYMBOL_GPL(usb_add_phy);
 701
 702static struct device_type usb_phy_dev_type = {
 703        .name = "usb_phy",
 704        .uevent = usb_phy_uevent,
 705};
 706
 707/**
 708 * usb_add_phy_dev - declare the USB PHY
 709 * @x: the USB phy to be used; or NULL
 710 *
 711 * This call is exclusively for use by phy drivers, which
 712 * coordinate the activities of drivers for host and peripheral
 713 * controllers, and in some cases for VBUS current regulation.
 714 */
 715int usb_add_phy_dev(struct usb_phy *x)
 716{
 717        unsigned long flags;
 718        int ret;
 719
 720        if (!x->dev) {
 721                dev_err(x->dev, "no device provided for PHY\n");
 722                return -EINVAL;
 723        }
 724
 725        usb_charger_init(x);
 726        ret = usb_add_extcon(x);
 727        if (ret)
 728                return ret;
 729
 730        x->dev->type = &usb_phy_dev_type;
 731
 732        ATOMIC_INIT_NOTIFIER_HEAD(&x->notifier);
 733
 734        spin_lock_irqsave(&phy_lock, flags);
 735        list_add_tail(&x->head, &phy_list);
 736        spin_unlock_irqrestore(&phy_lock, flags);
 737
 738        return 0;
 739}
 740EXPORT_SYMBOL_GPL(usb_add_phy_dev);
 741
 742/**
 743 * usb_remove_phy - remove the OTG PHY
 744 * @x: the USB OTG PHY to be removed;
 745 *
 746 * This reverts the effects of usb_add_phy
 747 */
 748void usb_remove_phy(struct usb_phy *x)
 749{
 750        unsigned long   flags;
 751
 752        spin_lock_irqsave(&phy_lock, flags);
 753        if (x)
 754                list_del(&x->head);
 755        spin_unlock_irqrestore(&phy_lock, flags);
 756}
 757EXPORT_SYMBOL_GPL(usb_remove_phy);
 758
 759/**
 760 * usb_phy_set_event - set event to phy event
 761 * @x: the phy returned by usb_get_phy();
 762 * @event: event to set
 763 *
 764 * This sets event to phy event
 765 */
 766void usb_phy_set_event(struct usb_phy *x, unsigned long event)
 767{
 768        x->last_event = event;
 769}
 770EXPORT_SYMBOL_GPL(usb_phy_set_event);
 771