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Note: File does not exist in v3.1.
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * phy-core.c  --  Generic Phy framework.
   4 *
   5 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   6 *
   7 * Author: Kishon Vijay Abraham I <kishon@ti.com>
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/export.h>
  12#include <linux/module.h>
  13#include <linux/err.h>
  14#include <linux/debugfs.h>
  15#include <linux/device.h>
  16#include <linux/slab.h>
  17#include <linux/of.h>
  18#include <linux/phy/phy.h>
  19#include <linux/idr.h>
  20#include <linux/pm_runtime.h>
  21#include <linux/regulator/consumer.h>
  22
  23static void phy_release(struct device *dev);
  24static const struct class phy_class = {
  25	.name = "phy",
  26	.dev_release = phy_release,
  27};
  28
  29static struct dentry *phy_debugfs_root;
  30static DEFINE_MUTEX(phy_provider_mutex);
  31static LIST_HEAD(phy_provider_list);
  32static LIST_HEAD(phys);
  33static DEFINE_IDA(phy_ida);
  34
  35static void devm_phy_release(struct device *dev, void *res)
  36{
  37	struct phy *phy = *(struct phy **)res;
  38
  39	phy_put(dev, phy);
  40}
  41
  42static void devm_phy_provider_release(struct device *dev, void *res)
  43{
  44	struct phy_provider *phy_provider = *(struct phy_provider **)res;
  45
  46	of_phy_provider_unregister(phy_provider);
  47}
  48
  49static void devm_phy_consume(struct device *dev, void *res)
  50{
  51	struct phy *phy = *(struct phy **)res;
  52
  53	phy_destroy(phy);
  54}
  55
  56static int devm_phy_match(struct device *dev, void *res, void *match_data)
  57{
  58	struct phy **phy = res;
  59
  60	return *phy == match_data;
  61}
  62
  63/**
  64 * phy_create_lookup() - allocate and register PHY/device association
  65 * @phy: the phy of the association
  66 * @con_id: connection ID string on device
  67 * @dev_id: the device of the association
  68 *
  69 * Creates and registers phy_lookup entry.
  70 */
  71int phy_create_lookup(struct phy *phy, const char *con_id, const char *dev_id)
  72{
  73	struct phy_lookup *pl;
  74
  75	if (!phy || !dev_id || !con_id)
  76		return -EINVAL;
  77
  78	pl = kzalloc(sizeof(*pl), GFP_KERNEL);
  79	if (!pl)
  80		return -ENOMEM;
  81
  82	pl->dev_id = dev_id;
  83	pl->con_id = con_id;
  84	pl->phy = phy;
  85
  86	mutex_lock(&phy_provider_mutex);
  87	list_add_tail(&pl->node, &phys);
  88	mutex_unlock(&phy_provider_mutex);
  89
  90	return 0;
  91}
  92EXPORT_SYMBOL_GPL(phy_create_lookup);
  93
  94/**
  95 * phy_remove_lookup() - find and remove PHY/device association
  96 * @phy: the phy of the association
  97 * @con_id: connection ID string on device
  98 * @dev_id: the device of the association
  99 *
 100 * Finds and unregisters phy_lookup entry that was created with
 101 * phy_create_lookup().
 102 */
 103void phy_remove_lookup(struct phy *phy, const char *con_id, const char *dev_id)
 104{
 105	struct phy_lookup *pl;
 106
 107	if (!phy || !dev_id || !con_id)
 108		return;
 109
 110	mutex_lock(&phy_provider_mutex);
 111	list_for_each_entry(pl, &phys, node)
 112		if (pl->phy == phy && !strcmp(pl->dev_id, dev_id) &&
 113		    !strcmp(pl->con_id, con_id)) {
 114			list_del(&pl->node);
 115			kfree(pl);
 116			break;
 117		}
 118	mutex_unlock(&phy_provider_mutex);
 119}
 120EXPORT_SYMBOL_GPL(phy_remove_lookup);
 121
 122static struct phy *phy_find(struct device *dev, const char *con_id)
 123{
 124	const char *dev_id = dev_name(dev);
 125	struct phy_lookup *p, *pl = NULL;
 126
 127	mutex_lock(&phy_provider_mutex);
 128	list_for_each_entry(p, &phys, node)
 129		if (!strcmp(p->dev_id, dev_id) && !strcmp(p->con_id, con_id)) {
 130			pl = p;
 131			break;
 132		}
 133	mutex_unlock(&phy_provider_mutex);
 134
 135	return pl ? pl->phy : ERR_PTR(-ENODEV);
 136}
 137
 138static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
 139{
 140	struct phy_provider *phy_provider;
 141	struct device_node *child;
 142
 143	list_for_each_entry(phy_provider, &phy_provider_list, list) {
 144		if (phy_provider->dev->of_node == node)
 145			return phy_provider;
 146
 147		for_each_child_of_node(phy_provider->children, child)
 148			if (child == node) {
 149				of_node_put(child);
 150				return phy_provider;
 151			}
 152	}
 153
 154	return ERR_PTR(-EPROBE_DEFER);
 155}
 156
 157int phy_pm_runtime_get(struct phy *phy)
 158{
 159	int ret;
 160
 161	if (!phy)
 162		return 0;
 163
 164	if (!pm_runtime_enabled(&phy->dev))
 165		return -ENOTSUPP;
 166
 167	ret = pm_runtime_get(&phy->dev);
 168	if (ret < 0 && ret != -EINPROGRESS)
 169		pm_runtime_put_noidle(&phy->dev);
 170
 171	return ret;
 172}
 173EXPORT_SYMBOL_GPL(phy_pm_runtime_get);
 174
 175int phy_pm_runtime_get_sync(struct phy *phy)
 176{
 177	int ret;
 178
 179	if (!phy)
 180		return 0;
 181
 182	if (!pm_runtime_enabled(&phy->dev))
 183		return -ENOTSUPP;
 184
 185	ret = pm_runtime_get_sync(&phy->dev);
 186	if (ret < 0)
 187		pm_runtime_put_sync(&phy->dev);
 188
 189	return ret;
 190}
 191EXPORT_SYMBOL_GPL(phy_pm_runtime_get_sync);
 192
 193int phy_pm_runtime_put(struct phy *phy)
 194{
 195	if (!phy)
 196		return 0;
 197
 198	if (!pm_runtime_enabled(&phy->dev))
 199		return -ENOTSUPP;
 200
 201	return pm_runtime_put(&phy->dev);
 202}
 203EXPORT_SYMBOL_GPL(phy_pm_runtime_put);
 204
 205int phy_pm_runtime_put_sync(struct phy *phy)
 206{
 207	if (!phy)
 208		return 0;
 209
 210	if (!pm_runtime_enabled(&phy->dev))
 211		return -ENOTSUPP;
 212
 213	return pm_runtime_put_sync(&phy->dev);
 214}
 215EXPORT_SYMBOL_GPL(phy_pm_runtime_put_sync);
 216
 217void phy_pm_runtime_allow(struct phy *phy)
 218{
 219	if (!phy)
 220		return;
 221
 222	if (!pm_runtime_enabled(&phy->dev))
 223		return;
 224
 225	pm_runtime_allow(&phy->dev);
 226}
 227EXPORT_SYMBOL_GPL(phy_pm_runtime_allow);
 228
 229void phy_pm_runtime_forbid(struct phy *phy)
 230{
 231	if (!phy)
 232		return;
 233
 234	if (!pm_runtime_enabled(&phy->dev))
 235		return;
 236
 237	pm_runtime_forbid(&phy->dev);
 238}
 239EXPORT_SYMBOL_GPL(phy_pm_runtime_forbid);
 240
 241/**
 242 * phy_init - phy internal initialization before phy operation
 243 * @phy: the phy returned by phy_get()
 244 *
 245 * Used to allow phy's driver to perform phy internal initialization,
 246 * such as PLL block powering, clock initialization or anything that's
 247 * is required by the phy to perform the start of operation.
 248 * Must be called before phy_power_on().
 249 *
 250 * Return: %0 if successful, a negative error code otherwise
 251 */
 252int phy_init(struct phy *phy)
 253{
 254	int ret;
 255
 256	if (!phy)
 257		return 0;
 258
 259	ret = phy_pm_runtime_get_sync(phy);
 260	if (ret < 0 && ret != -ENOTSUPP)
 261		return ret;
 262	ret = 0; /* Override possible ret == -ENOTSUPP */
 263
 264	mutex_lock(&phy->mutex);
 265	if (phy->power_count > phy->init_count)
 266		dev_warn(&phy->dev, "phy_power_on was called before phy_init\n");
 267
 268	if (phy->init_count == 0 && phy->ops->init) {
 269		ret = phy->ops->init(phy);
 270		if (ret < 0) {
 271			dev_err(&phy->dev, "phy init failed --> %d\n", ret);
 272			goto out;
 273		}
 274	}
 275	++phy->init_count;
 276
 277out:
 278	mutex_unlock(&phy->mutex);
 279	phy_pm_runtime_put(phy);
 280	return ret;
 281}
 282EXPORT_SYMBOL_GPL(phy_init);
 283
 284/**
 285 * phy_exit - Phy internal un-initialization
 286 * @phy: the phy returned by phy_get()
 287 *
 288 * Must be called after phy_power_off().
 289 *
 290 * Return: %0 if successful, a negative error code otherwise
 291 */
 292int phy_exit(struct phy *phy)
 293{
 294	int ret;
 295
 296	if (!phy)
 297		return 0;
 298
 299	ret = phy_pm_runtime_get_sync(phy);
 300	if (ret < 0 && ret != -ENOTSUPP)
 301		return ret;
 302	ret = 0; /* Override possible ret == -ENOTSUPP */
 303
 304	mutex_lock(&phy->mutex);
 305	if (phy->init_count == 1 && phy->ops->exit) {
 306		ret = phy->ops->exit(phy);
 307		if (ret < 0) {
 308			dev_err(&phy->dev, "phy exit failed --> %d\n", ret);
 309			goto out;
 310		}
 311	}
 312	--phy->init_count;
 313
 314out:
 315	mutex_unlock(&phy->mutex);
 316	phy_pm_runtime_put(phy);
 317	return ret;
 318}
 319EXPORT_SYMBOL_GPL(phy_exit);
 320
 321/**
 322 * phy_power_on - Enable the phy and enter proper operation
 323 * @phy: the phy returned by phy_get()
 324 *
 325 * Must be called after phy_init().
 326 *
 327 * Return: %0 if successful, a negative error code otherwise
 328 */
 329int phy_power_on(struct phy *phy)
 330{
 331	int ret = 0;
 332
 333	if (!phy)
 334		goto out;
 335
 336	if (phy->pwr) {
 337		ret = regulator_enable(phy->pwr);
 338		if (ret)
 339			goto out;
 340	}
 341
 342	ret = phy_pm_runtime_get_sync(phy);
 343	if (ret < 0 && ret != -ENOTSUPP)
 344		goto err_pm_sync;
 345
 346	ret = 0; /* Override possible ret == -ENOTSUPP */
 347
 348	mutex_lock(&phy->mutex);
 349	if (phy->power_count == 0 && phy->ops->power_on) {
 350		ret = phy->ops->power_on(phy);
 351		if (ret < 0) {
 352			dev_err(&phy->dev, "phy poweron failed --> %d\n", ret);
 353			goto err_pwr_on;
 354		}
 355	}
 356	++phy->power_count;
 357	mutex_unlock(&phy->mutex);
 358	return 0;
 359
 360err_pwr_on:
 361	mutex_unlock(&phy->mutex);
 362	phy_pm_runtime_put_sync(phy);
 363err_pm_sync:
 364	if (phy->pwr)
 365		regulator_disable(phy->pwr);
 366out:
 367	return ret;
 368}
 369EXPORT_SYMBOL_GPL(phy_power_on);
 370
 371/**
 372 * phy_power_off - Disable the phy.
 373 * @phy: the phy returned by phy_get()
 374 *
 375 * Must be called before phy_exit().
 376 *
 377 * Return: %0 if successful, a negative error code otherwise
 378 */
 379int phy_power_off(struct phy *phy)
 380{
 381	int ret;
 382
 383	if (!phy)
 384		return 0;
 385
 386	mutex_lock(&phy->mutex);
 387	if (phy->power_count == 1 && phy->ops->power_off) {
 388		ret =  phy->ops->power_off(phy);
 389		if (ret < 0) {
 390			dev_err(&phy->dev, "phy poweroff failed --> %d\n", ret);
 391			mutex_unlock(&phy->mutex);
 392			return ret;
 393		}
 394	}
 395	--phy->power_count;
 396	mutex_unlock(&phy->mutex);
 397	phy_pm_runtime_put(phy);
 398
 399	if (phy->pwr)
 400		regulator_disable(phy->pwr);
 401
 402	return 0;
 403}
 404EXPORT_SYMBOL_GPL(phy_power_off);
 405
 406int phy_set_mode_ext(struct phy *phy, enum phy_mode mode, int submode)
 407{
 408	int ret;
 409
 410	if (!phy || !phy->ops->set_mode)
 411		return 0;
 412
 413	mutex_lock(&phy->mutex);
 414	ret = phy->ops->set_mode(phy, mode, submode);
 415	if (!ret)
 416		phy->attrs.mode = mode;
 417	mutex_unlock(&phy->mutex);
 418
 419	return ret;
 420}
 421EXPORT_SYMBOL_GPL(phy_set_mode_ext);
 422
 423int phy_set_media(struct phy *phy, enum phy_media media)
 424{
 425	int ret;
 426
 427	if (!phy || !phy->ops->set_media)
 428		return 0;
 429
 430	mutex_lock(&phy->mutex);
 431	ret = phy->ops->set_media(phy, media);
 432	mutex_unlock(&phy->mutex);
 433
 434	return ret;
 435}
 436EXPORT_SYMBOL_GPL(phy_set_media);
 437
 438int phy_set_speed(struct phy *phy, int speed)
 439{
 440	int ret;
 441
 442	if (!phy || !phy->ops->set_speed)
 443		return 0;
 444
 445	mutex_lock(&phy->mutex);
 446	ret = phy->ops->set_speed(phy, speed);
 447	mutex_unlock(&phy->mutex);
 448
 449	return ret;
 450}
 451EXPORT_SYMBOL_GPL(phy_set_speed);
 452
 453int phy_reset(struct phy *phy)
 454{
 455	int ret;
 456
 457	if (!phy || !phy->ops->reset)
 458		return 0;
 459
 460	ret = phy_pm_runtime_get_sync(phy);
 461	if (ret < 0 && ret != -ENOTSUPP)
 462		return ret;
 463
 464	mutex_lock(&phy->mutex);
 465	ret = phy->ops->reset(phy);
 466	mutex_unlock(&phy->mutex);
 467
 468	phy_pm_runtime_put(phy);
 469
 470	return ret;
 471}
 472EXPORT_SYMBOL_GPL(phy_reset);
 473
 474/**
 475 * phy_calibrate() - Tunes the phy hw parameters for current configuration
 476 * @phy: the phy returned by phy_get()
 477 *
 478 * Used to calibrate phy hardware, typically by adjusting some parameters in
 479 * runtime, which are otherwise lost after host controller reset and cannot
 480 * be applied in phy_init() or phy_power_on().
 481 *
 482 * Return: %0 if successful, a negative error code otherwise
 483 */
 484int phy_calibrate(struct phy *phy)
 485{
 486	int ret;
 487
 488	if (!phy || !phy->ops->calibrate)
 489		return 0;
 490
 491	mutex_lock(&phy->mutex);
 492	ret = phy->ops->calibrate(phy);
 493	mutex_unlock(&phy->mutex);
 494
 495	return ret;
 496}
 497EXPORT_SYMBOL_GPL(phy_calibrate);
 498
 499/**
 500 * phy_notify_connect() - phy connect notification
 501 * @phy: the phy returned by phy_get()
 502 * @port: the port index for connect
 503 *
 504 * If the phy needs to get connection status, the callback can be used.
 505 * Returns: %0 if successful, a negative error code otherwise
 506 */
 507int phy_notify_connect(struct phy *phy, int port)
 508{
 509	int ret;
 510
 511	if (!phy || !phy->ops->connect)
 512		return 0;
 513
 514	mutex_lock(&phy->mutex);
 515	ret = phy->ops->connect(phy, port);
 516	mutex_unlock(&phy->mutex);
 517
 518	return ret;
 519}
 520EXPORT_SYMBOL_GPL(phy_notify_connect);
 521
 522/**
 523 * phy_notify_disconnect() - phy disconnect notification
 524 * @phy: the phy returned by phy_get()
 525 * @port: the port index for disconnect
 526 *
 527 * If the phy needs to get connection status, the callback can be used.
 528 *
 529 * Returns: %0 if successful, a negative error code otherwise
 530 */
 531int phy_notify_disconnect(struct phy *phy, int port)
 532{
 533	int ret;
 534
 535	if (!phy || !phy->ops->disconnect)
 536		return 0;
 537
 538	mutex_lock(&phy->mutex);
 539	ret = phy->ops->disconnect(phy, port);
 540	mutex_unlock(&phy->mutex);
 541
 542	return ret;
 543}
 544EXPORT_SYMBOL_GPL(phy_notify_disconnect);
 545
 546/**
 547 * phy_configure() - Changes the phy parameters
 548 * @phy: the phy returned by phy_get()
 549 * @opts: New configuration to apply
 550 *
 551 * Used to change the PHY parameters. phy_init() must have been called
 552 * on the phy. The configuration will be applied on the current phy
 553 * mode, that can be changed using phy_set_mode().
 554 *
 555 * Return: %0 if successful, a negative error code otherwise
 556 */
 557int phy_configure(struct phy *phy, union phy_configure_opts *opts)
 558{
 559	int ret;
 560
 561	if (!phy)
 562		return -EINVAL;
 563
 564	if (!phy->ops->configure)
 565		return -EOPNOTSUPP;
 566
 567	mutex_lock(&phy->mutex);
 568	ret = phy->ops->configure(phy, opts);
 569	mutex_unlock(&phy->mutex);
 570
 571	return ret;
 572}
 573EXPORT_SYMBOL_GPL(phy_configure);
 574
 575/**
 576 * phy_validate() - Checks the phy parameters
 577 * @phy: the phy returned by phy_get()
 578 * @mode: phy_mode the configuration is applicable to.
 579 * @submode: PHY submode the configuration is applicable to.
 580 * @opts: Configuration to check
 581 *
 582 * Used to check that the current set of parameters can be handled by
 583 * the phy. Implementations are free to tune the parameters passed as
 584 * arguments if needed by some implementation detail or
 585 * constraints. It will not change any actual configuration of the
 586 * PHY, so calling it as many times as deemed fit will have no side
 587 * effect.
 588 *
 589 * Return: %0 if successful, a negative error code otherwise
 590 */
 591int phy_validate(struct phy *phy, enum phy_mode mode, int submode,
 592		 union phy_configure_opts *opts)
 593{
 594	int ret;
 595
 596	if (!phy)
 597		return -EINVAL;
 598
 599	if (!phy->ops->validate)
 600		return -EOPNOTSUPP;
 601
 602	mutex_lock(&phy->mutex);
 603	ret = phy->ops->validate(phy, mode, submode, opts);
 604	mutex_unlock(&phy->mutex);
 605
 606	return ret;
 607}
 608EXPORT_SYMBOL_GPL(phy_validate);
 609
 610/**
 611 * _of_phy_get() - lookup and obtain a reference to a phy by phandle
 612 * @np: device_node for which to get the phy
 613 * @index: the index of the phy
 614 *
 615 * Returns the phy associated with the given phandle value,
 616 * after getting a refcount to it or -ENODEV if there is no such phy or
 617 * -EPROBE_DEFER if there is a phandle to the phy, but the device is
 618 * not yet loaded. This function uses of_xlate call back function provided
 619 * while registering the phy_provider to find the phy instance.
 620 */
 621static struct phy *_of_phy_get(struct device_node *np, int index)
 622{
 623	int ret;
 624	struct phy_provider *phy_provider;
 625	struct phy *phy = NULL;
 626	struct of_phandle_args args;
 627
 628	ret = of_parse_phandle_with_args(np, "phys", "#phy-cells",
 629		index, &args);
 630	if (ret)
 631		return ERR_PTR(-ENODEV);
 632
 633	/* This phy type handled by the usb-phy subsystem for now */
 634	if (of_device_is_compatible(args.np, "usb-nop-xceiv")) {
 635		phy = ERR_PTR(-ENODEV);
 636		goto out_put_node;
 637	}
 638
 639	mutex_lock(&phy_provider_mutex);
 640	phy_provider = of_phy_provider_lookup(args.np);
 641	if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner)) {
 642		phy = ERR_PTR(-EPROBE_DEFER);
 643		goto out_unlock;
 644	}
 645
 646	if (!of_device_is_available(args.np)) {
 647		dev_warn(phy_provider->dev, "Requested PHY is disabled\n");
 648		phy = ERR_PTR(-ENODEV);
 649		goto out_put_module;
 650	}
 651
 652	phy = phy_provider->of_xlate(phy_provider->dev, &args);
 653
 654out_put_module:
 655	module_put(phy_provider->owner);
 656
 657out_unlock:
 658	mutex_unlock(&phy_provider_mutex);
 659out_put_node:
 660	of_node_put(args.np);
 661
 662	return phy;
 663}
 664
 665/**
 666 * of_phy_get() - lookup and obtain a reference to a phy using a device_node.
 667 * @np: device_node for which to get the phy
 668 * @con_id: name of the phy from device's point of view
 669 *
 670 * Returns the phy driver, after getting a refcount to it; or
 671 * -ENODEV if there is no such phy. The caller is responsible for
 672 * calling of_phy_put() to release that count.
 673 */
 674struct phy *of_phy_get(struct device_node *np, const char *con_id)
 675{
 676	struct phy *phy = NULL;
 677	int index = 0;
 678
 679	if (con_id)
 680		index = of_property_match_string(np, "phy-names", con_id);
 681
 682	phy = _of_phy_get(np, index);
 683	if (IS_ERR(phy))
 684		return phy;
 685
 686	if (!try_module_get(phy->ops->owner))
 687		return ERR_PTR(-EPROBE_DEFER);
 688
 689	get_device(&phy->dev);
 690
 691	return phy;
 692}
 693EXPORT_SYMBOL_GPL(of_phy_get);
 694
 695/**
 696 * of_phy_put() - release the PHY
 697 * @phy: the phy returned by of_phy_get()
 698 *
 699 * Releases a refcount the caller received from of_phy_get().
 700 */
 701void of_phy_put(struct phy *phy)
 702{
 703	if (!phy || IS_ERR(phy))
 704		return;
 705
 706	mutex_lock(&phy->mutex);
 707	if (phy->ops->release)
 708		phy->ops->release(phy);
 709	mutex_unlock(&phy->mutex);
 710
 711	module_put(phy->ops->owner);
 712	put_device(&phy->dev);
 713}
 714EXPORT_SYMBOL_GPL(of_phy_put);
 715
 716/**
 717 * phy_put() - release the PHY
 718 * @dev: device that wants to release this phy
 719 * @phy: the phy returned by phy_get()
 720 *
 721 * Releases a refcount the caller received from phy_get().
 722 */
 723void phy_put(struct device *dev, struct phy *phy)
 724{
 725	device_link_remove(dev, &phy->dev);
 726	of_phy_put(phy);
 727}
 728EXPORT_SYMBOL_GPL(phy_put);
 729
 730/**
 731 * devm_phy_put() - release the PHY
 732 * @dev: device that wants to release this phy
 733 * @phy: the phy returned by devm_phy_get()
 734 *
 735 * destroys the devres associated with this phy and invokes phy_put
 736 * to release the phy.
 737 */
 738void devm_phy_put(struct device *dev, struct phy *phy)
 739{
 740	int r;
 741
 742	if (!phy)
 743		return;
 744
 745	r = devres_release(dev, devm_phy_release, devm_phy_match, phy);
 746	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
 747}
 748EXPORT_SYMBOL_GPL(devm_phy_put);
 749
 750/**
 751 * of_phy_simple_xlate() - returns the phy instance from phy provider
 752 * @dev: the PHY provider device
 753 * @args: of_phandle_args (not used here)
 754 *
 755 * Intended to be used by phy provider for the common case where #phy-cells is
 756 * 0. For other cases where #phy-cells is greater than '0', the phy provider
 757 * should provide a custom of_xlate function that reads the *args* and returns
 758 * the appropriate phy.
 759 */
 760struct phy *of_phy_simple_xlate(struct device *dev,
 761				const struct of_phandle_args *args)
 762{
 763	struct phy *phy;
 764	struct class_dev_iter iter;
 765
 766	class_dev_iter_init(&iter, &phy_class, NULL, NULL);
 767	while ((dev = class_dev_iter_next(&iter))) {
 768		phy = to_phy(dev);
 769		if (args->np != phy->dev.of_node)
 770			continue;
 771
 772		class_dev_iter_exit(&iter);
 773		return phy;
 774	}
 775
 776	class_dev_iter_exit(&iter);
 777	return ERR_PTR(-ENODEV);
 778}
 779EXPORT_SYMBOL_GPL(of_phy_simple_xlate);
 780
 781/**
 782 * phy_get() - lookup and obtain a reference to a phy.
 783 * @dev: device that requests this phy
 784 * @string: the phy name as given in the dt data or the name of the controller
 785 * port for non-dt case
 786 *
 787 * Returns the phy driver, after getting a refcount to it; or
 788 * -ENODEV if there is no such phy.  The caller is responsible for
 789 * calling phy_put() to release that count.
 790 */
 791struct phy *phy_get(struct device *dev, const char *string)
 792{
 793	int index = 0;
 794	struct phy *phy;
 795	struct device_link *link;
 796
 797	if (dev->of_node) {
 798		if (string)
 799			index = of_property_match_string(dev->of_node, "phy-names",
 800				string);
 801		else
 802			index = 0;
 803		phy = _of_phy_get(dev->of_node, index);
 804	} else {
 805		if (string == NULL) {
 806			dev_WARN(dev, "missing string\n");
 807			return ERR_PTR(-EINVAL);
 808		}
 809		phy = phy_find(dev, string);
 810	}
 811	if (IS_ERR(phy))
 812		return phy;
 813
 814	if (!try_module_get(phy->ops->owner))
 815		return ERR_PTR(-EPROBE_DEFER);
 816
 817	get_device(&phy->dev);
 818
 819	link = device_link_add(dev, &phy->dev, DL_FLAG_STATELESS);
 820	if (!link)
 821		dev_dbg(dev, "failed to create device link to %s\n",
 822			dev_name(phy->dev.parent));
 823
 824	return phy;
 825}
 826EXPORT_SYMBOL_GPL(phy_get);
 827
 828/**
 829 * devm_phy_get() - lookup and obtain a reference to a phy.
 830 * @dev: device that requests this phy
 831 * @string: the phy name as given in the dt data or phy device name
 832 * for non-dt case
 833 *
 834 * Gets the phy using phy_get(), and associates a device with it using
 835 * devres. On driver detach, release function is invoked on the devres data,
 836 * then, devres data is freed.
 837 */
 838struct phy *devm_phy_get(struct device *dev, const char *string)
 839{
 840	struct phy **ptr, *phy;
 841
 842	ptr = devres_alloc(devm_phy_release, sizeof(*ptr), GFP_KERNEL);
 843	if (!ptr)
 844		return ERR_PTR(-ENOMEM);
 845
 846	phy = phy_get(dev, string);
 847	if (!IS_ERR(phy)) {
 848		*ptr = phy;
 849		devres_add(dev, ptr);
 850	} else {
 851		devres_free(ptr);
 852	}
 853
 854	return phy;
 855}
 856EXPORT_SYMBOL_GPL(devm_phy_get);
 857
 858/**
 859 * devm_phy_optional_get() - lookup and obtain a reference to an optional phy.
 860 * @dev: device that requests this phy
 861 * @string: the phy name as given in the dt data or phy device name
 862 * for non-dt case
 863 *
 864 * Gets the phy using phy_get(), and associates a device with it using
 865 * devres. On driver detach, release function is invoked on the devres
 866 * data, then, devres data is freed. This differs to devm_phy_get() in
 867 * that if the phy does not exist, it is not considered an error and
 868 * -ENODEV will not be returned. Instead the NULL phy is returned,
 869 * which can be passed to all other phy consumer calls.
 870 */
 871struct phy *devm_phy_optional_get(struct device *dev, const char *string)
 872{
 873	struct phy *phy = devm_phy_get(dev, string);
 874
 875	if (PTR_ERR(phy) == -ENODEV)
 876		phy = NULL;
 877
 878	return phy;
 879}
 880EXPORT_SYMBOL_GPL(devm_phy_optional_get);
 881
 882/**
 883 * devm_of_phy_get() - lookup and obtain a reference to a phy.
 884 * @dev: device that requests this phy
 885 * @np: node containing the phy
 886 * @con_id: name of the phy from device's point of view
 887 *
 888 * Gets the phy using of_phy_get(), and associates a device with it using
 889 * devres. On driver detach, release function is invoked on the devres data,
 890 * then, devres data is freed.
 891 */
 892struct phy *devm_of_phy_get(struct device *dev, struct device_node *np,
 893			    const char *con_id)
 894{
 895	struct phy **ptr, *phy;
 896	struct device_link *link;
 897
 898	ptr = devres_alloc(devm_phy_release, sizeof(*ptr), GFP_KERNEL);
 899	if (!ptr)
 900		return ERR_PTR(-ENOMEM);
 901
 902	phy = of_phy_get(np, con_id);
 903	if (!IS_ERR(phy)) {
 904		*ptr = phy;
 905		devres_add(dev, ptr);
 906	} else {
 907		devres_free(ptr);
 908		return phy;
 909	}
 910
 911	link = device_link_add(dev, &phy->dev, DL_FLAG_STATELESS);
 912	if (!link)
 913		dev_dbg(dev, "failed to create device link to %s\n",
 914			dev_name(phy->dev.parent));
 915
 916	return phy;
 917}
 918EXPORT_SYMBOL_GPL(devm_of_phy_get);
 919
 920/**
 921 * devm_of_phy_optional_get() - lookup and obtain a reference to an optional
 922 * phy.
 923 * @dev: device that requests this phy
 924 * @np: node containing the phy
 925 * @con_id: name of the phy from device's point of view
 926 *
 927 * Gets the phy using of_phy_get(), and associates a device with it using
 928 * devres. On driver detach, release function is invoked on the devres data,
 929 * then, devres data is freed.  This differs to devm_of_phy_get() in
 930 * that if the phy does not exist, it is not considered an error and
 931 * -ENODEV will not be returned. Instead the NULL phy is returned,
 932 * which can be passed to all other phy consumer calls.
 933 */
 934struct phy *devm_of_phy_optional_get(struct device *dev, struct device_node *np,
 935				     const char *con_id)
 936{
 937	struct phy *phy = devm_of_phy_get(dev, np, con_id);
 938
 939	if (PTR_ERR(phy) == -ENODEV)
 940		phy = NULL;
 941
 942	if (IS_ERR(phy))
 943		dev_err_probe(dev, PTR_ERR(phy), "failed to get PHY %pOF:%s",
 944			      np, con_id);
 945
 946	return phy;
 947}
 948EXPORT_SYMBOL_GPL(devm_of_phy_optional_get);
 949
 950/**
 951 * devm_of_phy_get_by_index() - lookup and obtain a reference to a phy by index.
 952 * @dev: device that requests this phy
 953 * @np: node containing the phy
 954 * @index: index of the phy
 955 *
 956 * Gets the phy using _of_phy_get(), then gets a refcount to it,
 957 * and associates a device with it using devres. On driver detach,
 958 * release function is invoked on the devres data,
 959 * then, devres data is freed.
 960 *
 961 */
 962struct phy *devm_of_phy_get_by_index(struct device *dev, struct device_node *np,
 963				     int index)
 964{
 965	struct phy **ptr, *phy;
 966	struct device_link *link;
 967
 968	ptr = devres_alloc(devm_phy_release, sizeof(*ptr), GFP_KERNEL);
 969	if (!ptr)
 970		return ERR_PTR(-ENOMEM);
 971
 972	phy = _of_phy_get(np, index);
 973	if (IS_ERR(phy)) {
 974		devres_free(ptr);
 975		return phy;
 976	}
 977
 978	if (!try_module_get(phy->ops->owner)) {
 979		devres_free(ptr);
 980		return ERR_PTR(-EPROBE_DEFER);
 981	}
 982
 983	get_device(&phy->dev);
 984
 985	*ptr = phy;
 986	devres_add(dev, ptr);
 987
 988	link = device_link_add(dev, &phy->dev, DL_FLAG_STATELESS);
 989	if (!link)
 990		dev_dbg(dev, "failed to create device link to %s\n",
 991			dev_name(phy->dev.parent));
 992
 993	return phy;
 994}
 995EXPORT_SYMBOL_GPL(devm_of_phy_get_by_index);
 996
 997/**
 998 * phy_create() - create a new phy
 999 * @dev: device that is creating the new phy
1000 * @node: device node of the phy
1001 * @ops: function pointers for performing phy operations
1002 *
1003 * Called to create a phy using phy framework.
1004 */
1005struct phy *phy_create(struct device *dev, struct device_node *node,
1006		       const struct phy_ops *ops)
1007{
1008	int ret;
1009	int id;
1010	struct phy *phy;
1011
1012	if (WARN_ON(!dev))
1013		return ERR_PTR(-EINVAL);
1014
1015	phy = kzalloc(sizeof(*phy), GFP_KERNEL);
1016	if (!phy)
1017		return ERR_PTR(-ENOMEM);
1018
1019	id = ida_alloc(&phy_ida, GFP_KERNEL);
1020	if (id < 0) {
1021		dev_err(dev, "unable to get id\n");
1022		ret = id;
1023		goto free_phy;
1024	}
1025
1026	device_initialize(&phy->dev);
1027	mutex_init(&phy->mutex);
1028
1029	phy->dev.class = &phy_class;
1030	phy->dev.parent = dev;
1031	phy->dev.of_node = node ?: dev->of_node;
1032	phy->id = id;
1033	phy->ops = ops;
1034
1035	ret = dev_set_name(&phy->dev, "phy-%s.%d", dev_name(dev), id);
1036	if (ret)
1037		goto put_dev;
1038
1039	/* phy-supply */
1040	phy->pwr = regulator_get_optional(&phy->dev, "phy");
1041	if (IS_ERR(phy->pwr)) {
1042		ret = PTR_ERR(phy->pwr);
1043		if (ret == -EPROBE_DEFER)
1044			goto put_dev;
1045
1046		phy->pwr = NULL;
1047	}
1048
1049	ret = device_add(&phy->dev);
1050	if (ret)
1051		goto put_dev;
1052
1053	if (pm_runtime_enabled(dev)) {
1054		pm_runtime_enable(&phy->dev);
1055		pm_runtime_no_callbacks(&phy->dev);
1056	}
1057
1058	phy->debugfs = debugfs_create_dir(dev_name(&phy->dev), phy_debugfs_root);
1059
1060	return phy;
1061
1062put_dev:
1063	put_device(&phy->dev);  /* calls phy_release() which frees resources */
1064	return ERR_PTR(ret);
1065
1066free_phy:
1067	kfree(phy);
1068	return ERR_PTR(ret);
1069}
1070EXPORT_SYMBOL_GPL(phy_create);
1071
1072/**
1073 * devm_phy_create() - create a new phy
1074 * @dev: device that is creating the new phy
1075 * @node: device node of the phy
1076 * @ops: function pointers for performing phy operations
1077 *
1078 * Creates a new PHY device adding it to the PHY class.
1079 * While at that, it also associates the device with the phy using devres.
1080 * On driver detach, release function is invoked on the devres data,
1081 * then, devres data is freed.
1082 */
1083struct phy *devm_phy_create(struct device *dev, struct device_node *node,
1084			    const struct phy_ops *ops)
1085{
1086	struct phy **ptr, *phy;
1087
1088	ptr = devres_alloc(devm_phy_consume, sizeof(*ptr), GFP_KERNEL);
1089	if (!ptr)
1090		return ERR_PTR(-ENOMEM);
1091
1092	phy = phy_create(dev, node, ops);
1093	if (!IS_ERR(phy)) {
1094		*ptr = phy;
1095		devres_add(dev, ptr);
1096	} else {
1097		devres_free(ptr);
1098	}
1099
1100	return phy;
1101}
1102EXPORT_SYMBOL_GPL(devm_phy_create);
1103
1104/**
1105 * phy_destroy() - destroy the phy
1106 * @phy: the phy to be destroyed
1107 *
1108 * Called to destroy the phy.
1109 */
1110void phy_destroy(struct phy *phy)
1111{
1112	pm_runtime_disable(&phy->dev);
1113	device_unregister(&phy->dev);
1114}
1115EXPORT_SYMBOL_GPL(phy_destroy);
1116
1117/**
1118 * devm_phy_destroy() - destroy the PHY
1119 * @dev: device that wants to release this phy
1120 * @phy: the phy returned by devm_phy_get()
1121 *
1122 * destroys the devres associated with this phy and invokes phy_destroy
1123 * to destroy the phy.
1124 */
1125void devm_phy_destroy(struct device *dev, struct phy *phy)
1126{
1127	int r;
1128
1129	r = devres_release(dev, devm_phy_consume, devm_phy_match, phy);
1130	dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
1131}
1132EXPORT_SYMBOL_GPL(devm_phy_destroy);
1133
1134/**
1135 * __of_phy_provider_register() - create/register phy provider with the framework
1136 * @dev: struct device of the phy provider
1137 * @children: device node containing children (if different from dev->of_node)
1138 * @owner: the module owner containing of_xlate
1139 * @of_xlate: function pointer to obtain phy instance from phy provider
1140 *
1141 * Creates struct phy_provider from dev and of_xlate function pointer.
1142 * This is used in the case of dt boot for finding the phy instance from
1143 * phy provider.
1144 *
1145 * If the PHY provider doesn't nest children directly but uses a separate
1146 * child node to contain the individual children, the @children parameter
1147 * can be used to override the default. If NULL, the default (dev->of_node)
1148 * will be used. If non-NULL, the device node must be a child (or further
1149 * descendant) of dev->of_node. Otherwise an ERR_PTR()-encoded -EINVAL
1150 * error code is returned.
1151 */
1152struct phy_provider *__of_phy_provider_register(struct device *dev,
1153	struct device_node *children, struct module *owner,
1154	struct phy * (*of_xlate)(struct device *dev,
1155				 const struct of_phandle_args *args))
1156{
1157	struct phy_provider *phy_provider;
1158
1159	/*
1160	 * If specified, the device node containing the children must itself
1161	 * be the provider's device node or a child (or further descendant)
1162	 * thereof.
1163	 */
1164	if (children) {
1165		struct device_node *parent = of_node_get(children), *next;
1166
1167		while (parent) {
1168			if (parent == dev->of_node)
1169				break;
1170
1171			next = of_get_parent(parent);
1172			of_node_put(parent);
1173			parent = next;
1174		}
1175
1176		if (!parent)
1177			return ERR_PTR(-EINVAL);
1178
1179		of_node_put(parent);
1180	} else {
1181		children = dev->of_node;
1182	}
1183
1184	phy_provider = kzalloc(sizeof(*phy_provider), GFP_KERNEL);
1185	if (!phy_provider)
1186		return ERR_PTR(-ENOMEM);
1187
1188	phy_provider->dev = dev;
1189	phy_provider->children = of_node_get(children);
1190	phy_provider->owner = owner;
1191	phy_provider->of_xlate = of_xlate;
1192
1193	mutex_lock(&phy_provider_mutex);
1194	list_add_tail(&phy_provider->list, &phy_provider_list);
1195	mutex_unlock(&phy_provider_mutex);
1196
1197	return phy_provider;
1198}
1199EXPORT_SYMBOL_GPL(__of_phy_provider_register);
1200
1201/**
1202 * __devm_of_phy_provider_register() - create/register phy provider with the
1203 * framework
1204 * @dev: struct device of the phy provider
1205 * @children: device node containing children (if different from dev->of_node)
1206 * @owner: the module owner containing of_xlate
1207 * @of_xlate: function pointer to obtain phy instance from phy provider
1208 *
1209 * Creates struct phy_provider from dev and of_xlate function pointer.
1210 * This is used in the case of dt boot for finding the phy instance from
1211 * phy provider. While at that, it also associates the device with the
1212 * phy provider using devres. On driver detach, release function is invoked
1213 * on the devres data, then, devres data is freed.
1214 */
1215struct phy_provider *__devm_of_phy_provider_register(struct device *dev,
1216	struct device_node *children, struct module *owner,
1217	struct phy * (*of_xlate)(struct device *dev,
1218				 const struct of_phandle_args *args))
1219{
1220	struct phy_provider **ptr, *phy_provider;
1221
1222	ptr = devres_alloc(devm_phy_provider_release, sizeof(*ptr), GFP_KERNEL);
1223	if (!ptr)
1224		return ERR_PTR(-ENOMEM);
1225
1226	phy_provider = __of_phy_provider_register(dev, children, owner,
1227						  of_xlate);
1228	if (!IS_ERR(phy_provider)) {
1229		*ptr = phy_provider;
1230		devres_add(dev, ptr);
1231	} else {
1232		devres_free(ptr);
1233	}
1234
1235	return phy_provider;
1236}
1237EXPORT_SYMBOL_GPL(__devm_of_phy_provider_register);
1238
1239/**
1240 * of_phy_provider_unregister() - unregister phy provider from the framework
1241 * @phy_provider: phy provider returned by of_phy_provider_register()
1242 *
1243 * Removes the phy_provider created using of_phy_provider_register().
1244 */
1245void of_phy_provider_unregister(struct phy_provider *phy_provider)
1246{
1247	if (IS_ERR(phy_provider))
1248		return;
1249
1250	mutex_lock(&phy_provider_mutex);
1251	list_del(&phy_provider->list);
1252	of_node_put(phy_provider->children);
1253	kfree(phy_provider);
1254	mutex_unlock(&phy_provider_mutex);
1255}
1256EXPORT_SYMBOL_GPL(of_phy_provider_unregister);
1257
1258/**
1259 * devm_of_phy_provider_unregister() - remove phy provider from the framework
1260 * @dev: struct device of the phy provider
1261 * @phy_provider: phy provider returned by of_phy_provider_register()
1262 *
1263 * destroys the devres associated with this phy provider and invokes
1264 * of_phy_provider_unregister to unregister the phy provider.
1265 */
1266void devm_of_phy_provider_unregister(struct device *dev,
1267				     struct phy_provider *phy_provider)
1268{
1269	int r;
1270
1271	r = devres_release(dev, devm_phy_provider_release, devm_phy_match,
1272			   phy_provider);
1273	dev_WARN_ONCE(dev, r, "couldn't find PHY provider device resource\n");
1274}
1275EXPORT_SYMBOL_GPL(devm_of_phy_provider_unregister);
1276
1277/**
1278 * phy_release() - release the phy
1279 * @dev: the dev member within phy
1280 *
1281 * When the last reference to the device is removed, it is called
1282 * from the embedded kobject as release method.
1283 */
1284static void phy_release(struct device *dev)
1285{
1286	struct phy *phy;
1287
1288	phy = to_phy(dev);
1289	dev_vdbg(dev, "releasing '%s'\n", dev_name(dev));
1290	debugfs_remove_recursive(phy->debugfs);
1291	regulator_put(phy->pwr);
1292	ida_free(&phy_ida, phy->id);
1293	kfree(phy);
1294}
1295
1296static int __init phy_core_init(void)
1297{
1298	int err;
1299
1300	err = class_register(&phy_class);
1301	if (err) {
1302		pr_err("failed to register phy class");
1303		return err;
1304	}
1305
1306	phy_debugfs_root = debugfs_create_dir("phy", NULL);
1307
1308	return 0;
1309}
1310device_initcall(phy_core_init);
1311
1312static void __exit phy_core_exit(void)
1313{
1314	debugfs_remove_recursive(phy_debugfs_root);
1315	class_unregister(&phy_class);
1316}
1317module_exit(phy_core_exit);