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v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * platform.c - platform 'pseudo' bus for legacy devices
   4 *
   5 * Copyright (c) 2002-3 Patrick Mochel
   6 * Copyright (c) 2002-3 Open Source Development Labs
   7 *
   8 * Please see Documentation/driver-api/driver-model/platform.rst for more
   9 * information.
  10 */
  11
  12#include <linux/string.h>
  13#include <linux/platform_device.h>
  14#include <linux/of_device.h>
  15#include <linux/of_irq.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
 
 
  18#include <linux/dma-mapping.h>
  19#include <linux/memblock.h>
  20#include <linux/err.h>
  21#include <linux/slab.h>
  22#include <linux/pm_runtime.h>
  23#include <linux/pm_domain.h>
  24#include <linux/idr.h>
  25#include <linux/acpi.h>
  26#include <linux/clk/clk-conf.h>
  27#include <linux/limits.h>
  28#include <linux/property.h>
  29#include <linux/kmemleak.h>
  30#include <linux/types.h>
  31
  32#include "base.h"
  33#include "power/power.h"
  34
  35/* For automatically allocated device IDs */
  36static DEFINE_IDA(platform_devid_ida);
  37
  38struct device platform_bus = {
  39	.init_name	= "platform",
  40};
  41EXPORT_SYMBOL_GPL(platform_bus);
  42
  43/**
  44 * platform_get_resource - get a resource for a device
  45 * @dev: platform device
  46 * @type: resource type
  47 * @num: resource index
 
 
  48 */
  49struct resource *platform_get_resource(struct platform_device *dev,
  50				       unsigned int type, unsigned int num)
  51{
  52	u32 i;
  53
  54	for (i = 0; i < dev->num_resources; i++) {
  55		struct resource *r = &dev->resource[i];
  56
  57		if (type == resource_type(r) && num-- == 0)
  58			return r;
  59	}
  60	return NULL;
  61}
  62EXPORT_SYMBOL_GPL(platform_get_resource);
  63
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  64#ifdef CONFIG_HAS_IOMEM
  65/**
  66 * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
  67 *					    platform device and get resource
  68 *
  69 * @pdev: platform device to use both for memory resource lookup as well as
  70 *        resource management
  71 * @index: resource index
  72 * @res: optional output parameter to store a pointer to the obtained resource.
 
 
 
  73 */
  74void __iomem *
  75devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
  76				unsigned int index, struct resource **res)
  77{
  78	struct resource *r;
  79
  80	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
  81	if (res)
  82		*res = r;
  83	return devm_ioremap_resource(&pdev->dev, r);
  84}
  85EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
  86
  87/**
  88 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
  89 *				    device
  90 *
  91 * @pdev: platform device to use both for memory resource lookup as well as
  92 *        resource management
  93 * @index: resource index
 
 
 
  94 */
  95void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
  96					     unsigned int index)
  97{
  98	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
  99}
 100EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
 101
 102/**
 103 * devm_platform_ioremap_resource_wc - write-combined variant of
 104 *                                     devm_platform_ioremap_resource()
 105 *
 106 * @pdev: platform device to use both for memory resource lookup as well as
 107 *        resource management
 108 * @index: resource index
 109 */
 110void __iomem *devm_platform_ioremap_resource_wc(struct platform_device *pdev,
 111						unsigned int index)
 112{
 113	struct resource *res;
 114
 115	res = platform_get_resource(pdev, IORESOURCE_MEM, index);
 116	return devm_ioremap_resource_wc(&pdev->dev, res);
 117}
 118
 119/**
 120 * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
 121 *					   a platform device, retrieve the
 122 *					   resource by name
 123 *
 124 * @pdev: platform device to use both for memory resource lookup as well as
 125 *	  resource management
 126 * @name: name of the resource
 
 
 
 127 */
 128void __iomem *
 129devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 130				      const char *name)
 131{
 132	struct resource *res;
 133
 134	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 135	return devm_ioremap_resource(&pdev->dev, res);
 136}
 137EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
 138#endif /* CONFIG_HAS_IOMEM */
 139
 140/**
 141 * platform_get_irq_optional - get an optional IRQ for a device
 142 * @dev: platform device
 143 * @num: IRQ number index
 144 *
 145 * Gets an IRQ for a platform device. Device drivers should check the return
 146 * value for errors so as to not pass a negative integer value to the
 147 * request_irq() APIs. This is the same as platform_get_irq(), except that it
 148 * does not print an error message if an IRQ can not be obtained.
 149 *
 150 * For example::
 151 *
 152 *		int irq = platform_get_irq_optional(pdev, 0);
 153 *		if (irq < 0)
 154 *			return irq;
 155 *
 156 * Return: non-zero IRQ number on success, negative error number on failure.
 157 */
 158int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 159{
 160	int ret;
 161#ifdef CONFIG_SPARC
 162	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
 163	if (!dev || num >= dev->archdata.num_irqs)
 164		return -ENXIO;
 165	ret = dev->archdata.irqs[num];
 166	goto out;
 167#else
 168	struct resource *r;
 169
 170	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 171		ret = of_irq_get(dev->dev.of_node, num);
 172		if (ret > 0 || ret == -EPROBE_DEFER)
 173			goto out;
 174	}
 175
 176	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 177	if (has_acpi_companion(&dev->dev)) {
 178		if (r && r->flags & IORESOURCE_DISABLED) {
 179			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 180			if (ret)
 181				goto out;
 182		}
 183	}
 184
 185	/*
 186	 * The resources may pass trigger flags to the irqs that need
 187	 * to be set up. It so happens that the trigger flags for
 188	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 189	 * settings.
 190	 */
 191	if (r && r->flags & IORESOURCE_BITS) {
 192		struct irq_data *irqd;
 193
 194		irqd = irq_get_irq_data(r->start);
 195		if (!irqd) {
 196			ret = -ENXIO;
 197			goto out;
 198		}
 199		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 200	}
 201
 202	if (r) {
 203		ret = r->start;
 204		goto out;
 205	}
 206
 207	/*
 208	 * For the index 0 interrupt, allow falling back to GpioInt
 209	 * resources. While a device could have both Interrupt and GpioInt
 210	 * resources, making this fallback ambiguous, in many common cases
 211	 * the device will only expose one IRQ, and this fallback
 212	 * allows a common code path across either kind of resource.
 213	 */
 214	if (num == 0 && has_acpi_companion(&dev->dev)) {
 215		ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
 216		/* Our callers expect -ENXIO for missing IRQs. */
 217		if (ret >= 0 || ret == -EPROBE_DEFER)
 218			goto out;
 219	}
 220
 221	ret = -ENXIO;
 222#endif
 
 
 223out:
 224	WARN(ret == 0, "0 is an invalid IRQ number\n");
 225	return ret;
 226}
 227EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 228
 229/**
 230 * platform_get_irq - get an IRQ for a device
 231 * @dev: platform device
 232 * @num: IRQ number index
 233 *
 234 * Gets an IRQ for a platform device and prints an error message if finding the
 235 * IRQ fails. Device drivers should check the return value for errors so as to
 236 * not pass a negative integer value to the request_irq() APIs.
 237 *
 238 * For example::
 239 *
 240 *		int irq = platform_get_irq(pdev, 0);
 241 *		if (irq < 0)
 242 *			return irq;
 243 *
 244 * Return: non-zero IRQ number on success, negative error number on failure.
 245 */
 246int platform_get_irq(struct platform_device *dev, unsigned int num)
 247{
 248	int ret;
 249
 250	ret = platform_get_irq_optional(dev, num);
 251	if (ret < 0 && ret != -EPROBE_DEFER)
 252		dev_err(&dev->dev, "IRQ index %u not found\n", num);
 253
 254	return ret;
 255}
 256EXPORT_SYMBOL_GPL(platform_get_irq);
 257
 258/**
 259 * platform_irq_count - Count the number of IRQs a platform device uses
 260 * @dev: platform device
 261 *
 262 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 263 */
 264int platform_irq_count(struct platform_device *dev)
 265{
 266	int ret, nr = 0;
 267
 268	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
 269		nr++;
 270
 271	if (ret == -EPROBE_DEFER)
 272		return ret;
 273
 274	return nr;
 275}
 276EXPORT_SYMBOL_GPL(platform_irq_count);
 277
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 278/**
 279 * platform_get_resource_byname - get a resource for a device by name
 280 * @dev: platform device
 281 * @type: resource type
 282 * @name: resource name
 283 */
 284struct resource *platform_get_resource_byname(struct platform_device *dev,
 285					      unsigned int type,
 286					      const char *name)
 287{
 288	u32 i;
 289
 290	for (i = 0; i < dev->num_resources; i++) {
 291		struct resource *r = &dev->resource[i];
 292
 293		if (unlikely(!r->name))
 294			continue;
 295
 296		if (type == resource_type(r) && !strcmp(r->name, name))
 297			return r;
 298	}
 299	return NULL;
 300}
 301EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 302
 303static int __platform_get_irq_byname(struct platform_device *dev,
 304				     const char *name)
 305{
 306	struct resource *r;
 307	int ret;
 308
 309	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 310		ret = of_irq_get_byname(dev->dev.of_node, name);
 311		if (ret > 0 || ret == -EPROBE_DEFER)
 312			return ret;
 313	}
 314
 315	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 316	if (r) {
 317		WARN(r->start == 0, "0 is an invalid IRQ number\n");
 318		return r->start;
 319	}
 320
 321	return -ENXIO;
 322}
 323
 324/**
 325 * platform_get_irq_byname - get an IRQ for a device by name
 326 * @dev: platform device
 327 * @name: IRQ name
 328 *
 329 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
 330 *
 331 * Return: non-zero IRQ number on success, negative error number on failure.
 332 */
 333int platform_get_irq_byname(struct platform_device *dev, const char *name)
 334{
 335	int ret;
 336
 337	ret = __platform_get_irq_byname(dev, name);
 338	if (ret < 0 && ret != -EPROBE_DEFER)
 339		dev_err(&dev->dev, "IRQ %s not found\n", name);
 340
 341	return ret;
 342}
 343EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 344
 345/**
 346 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
 347 * @dev: platform device
 348 * @name: IRQ name
 349 *
 350 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
 351 * does not print an error message if an IRQ can not be obtained.
 352 *
 353 * Return: non-zero IRQ number on success, negative error number on failure.
 354 */
 355int platform_get_irq_byname_optional(struct platform_device *dev,
 356				     const char *name)
 357{
 358	return __platform_get_irq_byname(dev, name);
 359}
 360EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
 361
 362/**
 363 * platform_add_devices - add a numbers of platform devices
 364 * @devs: array of platform devices to add
 365 * @num: number of platform devices in array
 366 */
 367int platform_add_devices(struct platform_device **devs, int num)
 368{
 369	int i, ret = 0;
 370
 371	for (i = 0; i < num; i++) {
 372		ret = platform_device_register(devs[i]);
 373		if (ret) {
 374			while (--i >= 0)
 375				platform_device_unregister(devs[i]);
 376			break;
 377		}
 378	}
 379
 380	return ret;
 381}
 382EXPORT_SYMBOL_GPL(platform_add_devices);
 383
 384struct platform_object {
 385	struct platform_device pdev;
 386	char name[];
 387};
 388
 389/*
 390 * Set up default DMA mask for platform devices if the they weren't
 391 * previously set by the architecture / DT.
 392 */
 393static void setup_pdev_dma_masks(struct platform_device *pdev)
 394{
 395	pdev->dev.dma_parms = &pdev->dma_parms;
 396
 397	if (!pdev->dev.coherent_dma_mask)
 398		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 399	if (!pdev->dev.dma_mask) {
 400		pdev->platform_dma_mask = DMA_BIT_MASK(32);
 401		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 402	}
 403};
 404
 405/**
 406 * platform_device_put - destroy a platform device
 407 * @pdev: platform device to free
 408 *
 409 * Free all memory associated with a platform device.  This function must
 410 * _only_ be externally called in error cases.  All other usage is a bug.
 411 */
 412void platform_device_put(struct platform_device *pdev)
 413{
 414	if (!IS_ERR_OR_NULL(pdev))
 415		put_device(&pdev->dev);
 416}
 417EXPORT_SYMBOL_GPL(platform_device_put);
 418
 419static void platform_device_release(struct device *dev)
 420{
 421	struct platform_object *pa = container_of(dev, struct platform_object,
 422						  pdev.dev);
 423
 424	of_device_node_put(&pa->pdev.dev);
 425	kfree(pa->pdev.dev.platform_data);
 426	kfree(pa->pdev.mfd_cell);
 427	kfree(pa->pdev.resource);
 428	kfree(pa->pdev.driver_override);
 429	kfree(pa);
 430}
 431
 432/**
 433 * platform_device_alloc - create a platform device
 434 * @name: base name of the device we're adding
 435 * @id: instance id
 436 *
 437 * Create a platform device object which can have other objects attached
 438 * to it, and which will have attached objects freed when it is released.
 439 */
 440struct platform_device *platform_device_alloc(const char *name, int id)
 441{
 442	struct platform_object *pa;
 443
 444	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 445	if (pa) {
 446		strcpy(pa->name, name);
 447		pa->pdev.name = pa->name;
 448		pa->pdev.id = id;
 449		device_initialize(&pa->pdev.dev);
 450		pa->pdev.dev.release = platform_device_release;
 451		setup_pdev_dma_masks(&pa->pdev);
 452	}
 453
 454	return pa ? &pa->pdev : NULL;
 455}
 456EXPORT_SYMBOL_GPL(platform_device_alloc);
 457
 458/**
 459 * platform_device_add_resources - add resources to a platform device
 460 * @pdev: platform device allocated by platform_device_alloc to add resources to
 461 * @res: set of resources that needs to be allocated for the device
 462 * @num: number of resources
 463 *
 464 * Add a copy of the resources to the platform device.  The memory
 465 * associated with the resources will be freed when the platform device is
 466 * released.
 467 */
 468int platform_device_add_resources(struct platform_device *pdev,
 469				  const struct resource *res, unsigned int num)
 470{
 471	struct resource *r = NULL;
 472
 473	if (res) {
 474		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 475		if (!r)
 476			return -ENOMEM;
 477	}
 478
 479	kfree(pdev->resource);
 480	pdev->resource = r;
 481	pdev->num_resources = num;
 482	return 0;
 483}
 484EXPORT_SYMBOL_GPL(platform_device_add_resources);
 485
 486/**
 487 * platform_device_add_data - add platform-specific data to a platform device
 488 * @pdev: platform device allocated by platform_device_alloc to add resources to
 489 * @data: platform specific data for this platform device
 490 * @size: size of platform specific data
 491 *
 492 * Add a copy of platform specific data to the platform device's
 493 * platform_data pointer.  The memory associated with the platform data
 494 * will be freed when the platform device is released.
 495 */
 496int platform_device_add_data(struct platform_device *pdev, const void *data,
 497			     size_t size)
 498{
 499	void *d = NULL;
 500
 501	if (data) {
 502		d = kmemdup(data, size, GFP_KERNEL);
 503		if (!d)
 504			return -ENOMEM;
 505	}
 506
 507	kfree(pdev->dev.platform_data);
 508	pdev->dev.platform_data = d;
 509	return 0;
 510}
 511EXPORT_SYMBOL_GPL(platform_device_add_data);
 512
 513/**
 514 * platform_device_add_properties - add built-in properties to a platform device
 515 * @pdev: platform device to add properties to
 516 * @properties: null terminated array of properties to add
 517 *
 518 * The function will take deep copy of @properties and attach the copy to the
 519 * platform device. The memory associated with properties will be freed when the
 520 * platform device is released.
 521 */
 522int platform_device_add_properties(struct platform_device *pdev,
 523				   const struct property_entry *properties)
 524{
 525	return device_add_properties(&pdev->dev, properties);
 526}
 527EXPORT_SYMBOL_GPL(platform_device_add_properties);
 528
 529/**
 530 * platform_device_add - add a platform device to device hierarchy
 531 * @pdev: platform device we're adding
 532 *
 533 * This is part 2 of platform_device_register(), though may be called
 534 * separately _iff_ pdev was allocated by platform_device_alloc().
 535 */
 536int platform_device_add(struct platform_device *pdev)
 537{
 538	u32 i;
 539	int ret;
 540
 541	if (!pdev)
 542		return -EINVAL;
 543
 544	if (!pdev->dev.parent)
 545		pdev->dev.parent = &platform_bus;
 546
 547	pdev->dev.bus = &platform_bus_type;
 548
 549	switch (pdev->id) {
 550	default:
 551		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 552		break;
 553	case PLATFORM_DEVID_NONE:
 554		dev_set_name(&pdev->dev, "%s", pdev->name);
 555		break;
 556	case PLATFORM_DEVID_AUTO:
 557		/*
 558		 * Automatically allocated device ID. We mark it as such so
 559		 * that we remember it must be freed, and we append a suffix
 560		 * to avoid namespace collision with explicit IDs.
 561		 */
 562		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 563		if (ret < 0)
 564			goto err_out;
 565		pdev->id = ret;
 566		pdev->id_auto = true;
 567		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 568		break;
 569	}
 570
 571	for (i = 0; i < pdev->num_resources; i++) {
 572		struct resource *p, *r = &pdev->resource[i];
 573
 574		if (r->name == NULL)
 575			r->name = dev_name(&pdev->dev);
 576
 577		p = r->parent;
 578		if (!p) {
 579			if (resource_type(r) == IORESOURCE_MEM)
 580				p = &iomem_resource;
 581			else if (resource_type(r) == IORESOURCE_IO)
 582				p = &ioport_resource;
 583		}
 584
 585		if (p) {
 586			ret = insert_resource(p, r);
 587			if (ret) {
 588				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 589				goto failed;
 590			}
 591		}
 592	}
 593
 594	pr_debug("Registering platform device '%s'. Parent at %s\n",
 595		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 596
 597	ret = device_add(&pdev->dev);
 598	if (ret == 0)
 599		return ret;
 600
 601 failed:
 602	if (pdev->id_auto) {
 603		ida_simple_remove(&platform_devid_ida, pdev->id);
 604		pdev->id = PLATFORM_DEVID_AUTO;
 605	}
 606
 607	while (i--) {
 608		struct resource *r = &pdev->resource[i];
 609		if (r->parent)
 610			release_resource(r);
 611	}
 612
 613 err_out:
 614	return ret;
 615}
 616EXPORT_SYMBOL_GPL(platform_device_add);
 617
 618/**
 619 * platform_device_del - remove a platform-level device
 620 * @pdev: platform device we're removing
 621 *
 622 * Note that this function will also release all memory- and port-based
 623 * resources owned by the device (@dev->resource).  This function must
 624 * _only_ be externally called in error cases.  All other usage is a bug.
 625 */
 626void platform_device_del(struct platform_device *pdev)
 627{
 628	u32 i;
 629
 630	if (!IS_ERR_OR_NULL(pdev)) {
 631		device_del(&pdev->dev);
 632
 633		if (pdev->id_auto) {
 634			ida_simple_remove(&platform_devid_ida, pdev->id);
 635			pdev->id = PLATFORM_DEVID_AUTO;
 636		}
 637
 638		for (i = 0; i < pdev->num_resources; i++) {
 639			struct resource *r = &pdev->resource[i];
 640			if (r->parent)
 641				release_resource(r);
 642		}
 643	}
 644}
 645EXPORT_SYMBOL_GPL(platform_device_del);
 646
 647/**
 648 * platform_device_register - add a platform-level device
 649 * @pdev: platform device we're adding
 650 */
 651int platform_device_register(struct platform_device *pdev)
 652{
 653	device_initialize(&pdev->dev);
 654	setup_pdev_dma_masks(pdev);
 655	return platform_device_add(pdev);
 656}
 657EXPORT_SYMBOL_GPL(platform_device_register);
 658
 659/**
 660 * platform_device_unregister - unregister a platform-level device
 661 * @pdev: platform device we're unregistering
 662 *
 663 * Unregistration is done in 2 steps. First we release all resources
 664 * and remove it from the subsystem, then we drop reference count by
 665 * calling platform_device_put().
 666 */
 667void platform_device_unregister(struct platform_device *pdev)
 668{
 669	platform_device_del(pdev);
 670	platform_device_put(pdev);
 671}
 672EXPORT_SYMBOL_GPL(platform_device_unregister);
 673
 674/**
 675 * platform_device_register_full - add a platform-level device with
 676 * resources and platform-specific data
 677 *
 678 * @pdevinfo: data used to create device
 679 *
 680 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 681 */
 682struct platform_device *platform_device_register_full(
 683		const struct platform_device_info *pdevinfo)
 684{
 685	int ret;
 686	struct platform_device *pdev;
 687
 688	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 689	if (!pdev)
 690		return ERR_PTR(-ENOMEM);
 691
 692	pdev->dev.parent = pdevinfo->parent;
 693	pdev->dev.fwnode = pdevinfo->fwnode;
 694	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
 695	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
 696
 697	if (pdevinfo->dma_mask) {
 698		pdev->platform_dma_mask = pdevinfo->dma_mask;
 699		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 700		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 701	}
 702
 703	ret = platform_device_add_resources(pdev,
 704			pdevinfo->res, pdevinfo->num_res);
 705	if (ret)
 706		goto err;
 707
 708	ret = platform_device_add_data(pdev,
 709			pdevinfo->data, pdevinfo->size_data);
 710	if (ret)
 711		goto err;
 712
 713	if (pdevinfo->properties) {
 714		ret = platform_device_add_properties(pdev,
 715						     pdevinfo->properties);
 716		if (ret)
 717			goto err;
 718	}
 719
 720	ret = platform_device_add(pdev);
 721	if (ret) {
 722err:
 723		ACPI_COMPANION_SET(&pdev->dev, NULL);
 724		platform_device_put(pdev);
 725		return ERR_PTR(ret);
 726	}
 727
 728	return pdev;
 729}
 730EXPORT_SYMBOL_GPL(platform_device_register_full);
 731
 732static int platform_drv_probe(struct device *_dev)
 733{
 734	struct platform_driver *drv = to_platform_driver(_dev->driver);
 735	struct platform_device *dev = to_platform_device(_dev);
 736	int ret;
 737
 738	ret = of_clk_set_defaults(_dev->of_node, false);
 739	if (ret < 0)
 740		return ret;
 741
 742	ret = dev_pm_domain_attach(_dev, true);
 743	if (ret)
 744		goto out;
 745
 746	if (drv->probe) {
 747		ret = drv->probe(dev);
 748		if (ret)
 749			dev_pm_domain_detach(_dev, true);
 750	}
 751
 752out:
 753	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 754		dev_warn(_dev, "probe deferral not supported\n");
 755		ret = -ENXIO;
 756	}
 757
 758	return ret;
 759}
 760
 761static int platform_drv_probe_fail(struct device *_dev)
 762{
 763	return -ENXIO;
 764}
 765
 766static int platform_drv_remove(struct device *_dev)
 767{
 768	struct platform_driver *drv = to_platform_driver(_dev->driver);
 769	struct platform_device *dev = to_platform_device(_dev);
 770	int ret = 0;
 771
 772	if (drv->remove)
 773		ret = drv->remove(dev);
 774	dev_pm_domain_detach(_dev, true);
 775
 776	return ret;
 777}
 778
 779static void platform_drv_shutdown(struct device *_dev)
 780{
 781	struct platform_driver *drv = to_platform_driver(_dev->driver);
 782	struct platform_device *dev = to_platform_device(_dev);
 783
 784	if (drv->shutdown)
 785		drv->shutdown(dev);
 786}
 787
 788/**
 789 * __platform_driver_register - register a driver for platform-level devices
 790 * @drv: platform driver structure
 791 * @owner: owning module/driver
 792 */
 793int __platform_driver_register(struct platform_driver *drv,
 794				struct module *owner)
 795{
 796	drv->driver.owner = owner;
 797	drv->driver.bus = &platform_bus_type;
 798	drv->driver.probe = platform_drv_probe;
 799	drv->driver.remove = platform_drv_remove;
 800	drv->driver.shutdown = platform_drv_shutdown;
 801
 802	return driver_register(&drv->driver);
 803}
 804EXPORT_SYMBOL_GPL(__platform_driver_register);
 805
 806/**
 807 * platform_driver_unregister - unregister a driver for platform-level devices
 808 * @drv: platform driver structure
 809 */
 810void platform_driver_unregister(struct platform_driver *drv)
 811{
 812	driver_unregister(&drv->driver);
 813}
 814EXPORT_SYMBOL_GPL(platform_driver_unregister);
 815
 
 
 
 
 
 816/**
 817 * __platform_driver_probe - register driver for non-hotpluggable device
 818 * @drv: platform driver structure
 819 * @probe: the driver probe routine, probably from an __init section
 820 * @module: module which will be the owner of the driver
 821 *
 822 * Use this instead of platform_driver_register() when you know the device
 823 * is not hotpluggable and has already been registered, and you want to
 824 * remove its run-once probe() infrastructure from memory after the driver
 825 * has bound to the device.
 826 *
 827 * One typical use for this would be with drivers for controllers integrated
 828 * into system-on-chip processors, where the controller devices have been
 829 * configured as part of board setup.
 830 *
 831 * Note that this is incompatible with deferred probing.
 832 *
 833 * Returns zero if the driver registered and bound to a device, else returns
 834 * a negative error code and with the driver not registered.
 835 */
 836int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 837		int (*probe)(struct platform_device *), struct module *module)
 838{
 839	int retval, code;
 840
 841	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 842		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 843			 drv->driver.name, __func__);
 844		return -EINVAL;
 845	}
 846
 847	/*
 848	 * We have to run our probes synchronously because we check if
 849	 * we find any devices to bind to and exit with error if there
 850	 * are any.
 851	 */
 852	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 853
 854	/*
 855	 * Prevent driver from requesting probe deferral to avoid further
 856	 * futile probe attempts.
 857	 */
 858	drv->prevent_deferred_probe = true;
 859
 860	/* make sure driver won't have bind/unbind attributes */
 861	drv->driver.suppress_bind_attrs = true;
 862
 863	/* temporary section violation during probe() */
 864	drv->probe = probe;
 865	retval = code = __platform_driver_register(drv, module);
 866	if (retval)
 867		return retval;
 868
 869	/*
 870	 * Fixup that section violation, being paranoid about code scanning
 871	 * the list of drivers in order to probe new devices.  Check to see
 872	 * if the probe was successful, and make sure any forced probes of
 873	 * new devices fail.
 874	 */
 875	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 876	drv->probe = NULL;
 877	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 878		retval = -ENODEV;
 879	drv->driver.probe = platform_drv_probe_fail;
 880	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 881
 882	if (code != retval)
 883		platform_driver_unregister(drv);
 884	return retval;
 885}
 886EXPORT_SYMBOL_GPL(__platform_driver_probe);
 887
 888/**
 889 * __platform_create_bundle - register driver and create corresponding device
 890 * @driver: platform driver structure
 891 * @probe: the driver probe routine, probably from an __init section
 892 * @res: set of resources that needs to be allocated for the device
 893 * @n_res: number of resources
 894 * @data: platform specific data for this platform device
 895 * @size: size of platform specific data
 896 * @module: module which will be the owner of the driver
 897 *
 898 * Use this in legacy-style modules that probe hardware directly and
 899 * register a single platform device and corresponding platform driver.
 900 *
 901 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 902 */
 903struct platform_device * __init_or_module __platform_create_bundle(
 904			struct platform_driver *driver,
 905			int (*probe)(struct platform_device *),
 906			struct resource *res, unsigned int n_res,
 907			const void *data, size_t size, struct module *module)
 908{
 909	struct platform_device *pdev;
 910	int error;
 911
 912	pdev = platform_device_alloc(driver->driver.name, -1);
 913	if (!pdev) {
 914		error = -ENOMEM;
 915		goto err_out;
 916	}
 917
 918	error = platform_device_add_resources(pdev, res, n_res);
 919	if (error)
 920		goto err_pdev_put;
 921
 922	error = platform_device_add_data(pdev, data, size);
 923	if (error)
 924		goto err_pdev_put;
 925
 926	error = platform_device_add(pdev);
 927	if (error)
 928		goto err_pdev_put;
 929
 930	error = __platform_driver_probe(driver, probe, module);
 931	if (error)
 932		goto err_pdev_del;
 933
 934	return pdev;
 935
 936err_pdev_del:
 937	platform_device_del(pdev);
 938err_pdev_put:
 939	platform_device_put(pdev);
 940err_out:
 941	return ERR_PTR(error);
 942}
 943EXPORT_SYMBOL_GPL(__platform_create_bundle);
 944
 945/**
 946 * __platform_register_drivers - register an array of platform drivers
 947 * @drivers: an array of drivers to register
 948 * @count: the number of drivers to register
 949 * @owner: module owning the drivers
 950 *
 951 * Registers platform drivers specified by an array. On failure to register a
 952 * driver, all previously registered drivers will be unregistered. Callers of
 953 * this API should use platform_unregister_drivers() to unregister drivers in
 954 * the reverse order.
 955 *
 956 * Returns: 0 on success or a negative error code on failure.
 957 */
 958int __platform_register_drivers(struct platform_driver * const *drivers,
 959				unsigned int count, struct module *owner)
 960{
 961	unsigned int i;
 962	int err;
 963
 964	for (i = 0; i < count; i++) {
 965		pr_debug("registering platform driver %ps\n", drivers[i]);
 966
 967		err = __platform_driver_register(drivers[i], owner);
 968		if (err < 0) {
 969			pr_err("failed to register platform driver %ps: %d\n",
 970			       drivers[i], err);
 971			goto error;
 972		}
 973	}
 974
 975	return 0;
 976
 977error:
 978	while (i--) {
 979		pr_debug("unregistering platform driver %ps\n", drivers[i]);
 980		platform_driver_unregister(drivers[i]);
 981	}
 982
 983	return err;
 984}
 985EXPORT_SYMBOL_GPL(__platform_register_drivers);
 986
 987/**
 988 * platform_unregister_drivers - unregister an array of platform drivers
 989 * @drivers: an array of drivers to unregister
 990 * @count: the number of drivers to unregister
 991 *
 992 * Unregisters platform drivers specified by an array. This is typically used
 993 * to complement an earlier call to platform_register_drivers(). Drivers are
 994 * unregistered in the reverse order in which they were registered.
 995 */
 996void platform_unregister_drivers(struct platform_driver * const *drivers,
 997				 unsigned int count)
 998{
 999	while (count--) {
1000		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1001		platform_driver_unregister(drivers[count]);
1002	}
1003}
1004EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1005
1006/* modalias support enables more hands-off userspace setup:
1007 * (a) environment variable lets new-style hotplug events work once system is
1008 *     fully running:  "modprobe $MODALIAS"
1009 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1010 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1011 */
1012static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
1013			     char *buf)
1014{
1015	struct platform_device	*pdev = to_platform_device(dev);
1016	int len;
1017
1018	len = of_device_modalias(dev, buf, PAGE_SIZE);
1019	if (len != -ENODEV)
1020		return len;
1021
1022	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1023	if (len != -ENODEV)
1024		return len;
1025
1026	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
1027
1028	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
1029}
1030static DEVICE_ATTR_RO(modalias);
1031
1032static ssize_t driver_override_store(struct device *dev,
1033				     struct device_attribute *attr,
1034				     const char *buf, size_t count)
1035{
1036	struct platform_device *pdev = to_platform_device(dev);
1037	char *driver_override, *old, *cp;
1038
1039	/* We need to keep extra room for a newline */
1040	if (count >= (PAGE_SIZE - 1))
1041		return -EINVAL;
1042
1043	driver_override = kstrndup(buf, count, GFP_KERNEL);
1044	if (!driver_override)
1045		return -ENOMEM;
1046
1047	cp = strchr(driver_override, '\n');
1048	if (cp)
1049		*cp = '\0';
1050
1051	device_lock(dev);
1052	old = pdev->driver_override;
1053	if (strlen(driver_override)) {
1054		pdev->driver_override = driver_override;
1055	} else {
1056		kfree(driver_override);
1057		pdev->driver_override = NULL;
1058	}
1059	device_unlock(dev);
1060
1061	kfree(old);
1062
1063	return count;
1064}
1065
1066static ssize_t driver_override_show(struct device *dev,
1067				    struct device_attribute *attr, char *buf)
1068{
1069	struct platform_device *pdev = to_platform_device(dev);
1070	ssize_t len;
1071
1072	device_lock(dev);
1073	len = sprintf(buf, "%s\n", pdev->driver_override);
1074	device_unlock(dev);
1075	return len;
1076}
1077static DEVICE_ATTR_RW(driver_override);
1078
1079static ssize_t numa_node_show(struct device *dev,
1080		struct device_attribute *attr, char *buf)
1081{
1082	return sprintf(buf, "%d\n", dev_to_node(dev));
1083}
1084static DEVICE_ATTR_RO(numa_node);
1085
1086static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1087		int n)
1088{
1089	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1090
1091	if (a == &dev_attr_numa_node.attr &&
1092			dev_to_node(dev) == NUMA_NO_NODE)
1093		return 0;
1094
1095	return a->mode;
1096}
1097
1098static struct attribute *platform_dev_attrs[] = {
1099	&dev_attr_modalias.attr,
1100	&dev_attr_numa_node.attr,
1101	&dev_attr_driver_override.attr,
1102	NULL,
1103};
1104
1105static struct attribute_group platform_dev_group = {
1106	.attrs = platform_dev_attrs,
1107	.is_visible = platform_dev_attrs_visible,
1108};
1109__ATTRIBUTE_GROUPS(platform_dev);
1110
1111static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1112{
1113	struct platform_device	*pdev = to_platform_device(dev);
1114	int rc;
1115
1116	/* Some devices have extra OF data and an OF-style MODALIAS */
1117	rc = of_device_uevent_modalias(dev, env);
1118	if (rc != -ENODEV)
1119		return rc;
1120
1121	rc = acpi_device_uevent_modalias(dev, env);
1122	if (rc != -ENODEV)
1123		return rc;
1124
1125	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1126			pdev->name);
1127	return 0;
1128}
1129
1130static const struct platform_device_id *platform_match_id(
1131			const struct platform_device_id *id,
1132			struct platform_device *pdev)
1133{
1134	while (id->name[0]) {
1135		if (strcmp(pdev->name, id->name) == 0) {
1136			pdev->id_entry = id;
1137			return id;
1138		}
1139		id++;
1140	}
1141	return NULL;
1142}
1143
1144/**
1145 * platform_match - bind platform device to platform driver.
1146 * @dev: device.
1147 * @drv: driver.
1148 *
1149 * Platform device IDs are assumed to be encoded like this:
1150 * "<name><instance>", where <name> is a short description of the type of
1151 * device, like "pci" or "floppy", and <instance> is the enumerated
1152 * instance of the device, like '0' or '42'.  Driver IDs are simply
1153 * "<name>".  So, extract the <name> from the platform_device structure,
1154 * and compare it against the name of the driver. Return whether they match
1155 * or not.
1156 */
1157static int platform_match(struct device *dev, struct device_driver *drv)
1158{
1159	struct platform_device *pdev = to_platform_device(dev);
1160	struct platform_driver *pdrv = to_platform_driver(drv);
1161
1162	/* When driver_override is set, only bind to the matching driver */
1163	if (pdev->driver_override)
1164		return !strcmp(pdev->driver_override, drv->name);
1165
1166	/* Attempt an OF style match first */
1167	if (of_driver_match_device(dev, drv))
1168		return 1;
1169
1170	/* Then try ACPI style match */
1171	if (acpi_driver_match_device(dev, drv))
1172		return 1;
1173
1174	/* Then try to match against the id table */
1175	if (pdrv->id_table)
1176		return platform_match_id(pdrv->id_table, pdev) != NULL;
1177
1178	/* fall-back to driver name match */
1179	return (strcmp(pdev->name, drv->name) == 0);
1180}
1181
1182#ifdef CONFIG_PM_SLEEP
1183
1184static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1185{
1186	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1187	struct platform_device *pdev = to_platform_device(dev);
1188	int ret = 0;
1189
1190	if (dev->driver && pdrv->suspend)
1191		ret = pdrv->suspend(pdev, mesg);
1192
1193	return ret;
1194}
1195
1196static int platform_legacy_resume(struct device *dev)
1197{
1198	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1199	struct platform_device *pdev = to_platform_device(dev);
1200	int ret = 0;
1201
1202	if (dev->driver && pdrv->resume)
1203		ret = pdrv->resume(pdev);
1204
1205	return ret;
1206}
1207
1208#endif /* CONFIG_PM_SLEEP */
1209
1210#ifdef CONFIG_SUSPEND
1211
1212int platform_pm_suspend(struct device *dev)
1213{
1214	struct device_driver *drv = dev->driver;
1215	int ret = 0;
1216
1217	if (!drv)
1218		return 0;
1219
1220	if (drv->pm) {
1221		if (drv->pm->suspend)
1222			ret = drv->pm->suspend(dev);
1223	} else {
1224		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1225	}
1226
1227	return ret;
1228}
1229
1230int platform_pm_resume(struct device *dev)
1231{
1232	struct device_driver *drv = dev->driver;
1233	int ret = 0;
1234
1235	if (!drv)
1236		return 0;
1237
1238	if (drv->pm) {
1239		if (drv->pm->resume)
1240			ret = drv->pm->resume(dev);
1241	} else {
1242		ret = platform_legacy_resume(dev);
1243	}
1244
1245	return ret;
1246}
1247
1248#endif /* CONFIG_SUSPEND */
1249
1250#ifdef CONFIG_HIBERNATE_CALLBACKS
1251
1252int platform_pm_freeze(struct device *dev)
1253{
1254	struct device_driver *drv = dev->driver;
1255	int ret = 0;
1256
1257	if (!drv)
1258		return 0;
1259
1260	if (drv->pm) {
1261		if (drv->pm->freeze)
1262			ret = drv->pm->freeze(dev);
1263	} else {
1264		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1265	}
1266
1267	return ret;
1268}
1269
1270int platform_pm_thaw(struct device *dev)
1271{
1272	struct device_driver *drv = dev->driver;
1273	int ret = 0;
1274
1275	if (!drv)
1276		return 0;
1277
1278	if (drv->pm) {
1279		if (drv->pm->thaw)
1280			ret = drv->pm->thaw(dev);
1281	} else {
1282		ret = platform_legacy_resume(dev);
1283	}
1284
1285	return ret;
1286}
1287
1288int platform_pm_poweroff(struct device *dev)
1289{
1290	struct device_driver *drv = dev->driver;
1291	int ret = 0;
1292
1293	if (!drv)
1294		return 0;
1295
1296	if (drv->pm) {
1297		if (drv->pm->poweroff)
1298			ret = drv->pm->poweroff(dev);
1299	} else {
1300		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1301	}
1302
1303	return ret;
1304}
1305
1306int platform_pm_restore(struct device *dev)
1307{
1308	struct device_driver *drv = dev->driver;
1309	int ret = 0;
1310
1311	if (!drv)
1312		return 0;
1313
1314	if (drv->pm) {
1315		if (drv->pm->restore)
1316			ret = drv->pm->restore(dev);
1317	} else {
1318		ret = platform_legacy_resume(dev);
1319	}
1320
1321	return ret;
1322}
1323
1324#endif /* CONFIG_HIBERNATE_CALLBACKS */
1325
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1326int platform_dma_configure(struct device *dev)
1327{
1328	enum dev_dma_attr attr;
1329	int ret = 0;
1330
1331	if (dev->of_node) {
1332		ret = of_dma_configure(dev, dev->of_node, true);
1333	} else if (has_acpi_companion(dev)) {
1334		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1335		ret = acpi_dma_configure(dev, attr);
1336	}
1337
1338	return ret;
1339}
1340
1341static const struct dev_pm_ops platform_dev_pm_ops = {
1342	.runtime_suspend = pm_generic_runtime_suspend,
1343	.runtime_resume = pm_generic_runtime_resume,
1344	USE_PLATFORM_PM_SLEEP_OPS
1345};
1346
1347struct bus_type platform_bus_type = {
1348	.name		= "platform",
1349	.dev_groups	= platform_dev_groups,
1350	.match		= platform_match,
1351	.uevent		= platform_uevent,
 
 
 
1352	.dma_configure	= platform_dma_configure,
1353	.pm		= &platform_dev_pm_ops,
1354};
1355EXPORT_SYMBOL_GPL(platform_bus_type);
1356
1357static inline int __platform_match(struct device *dev, const void *drv)
1358{
1359	return platform_match(dev, (struct device_driver *)drv);
1360}
1361
1362/**
1363 * platform_find_device_by_driver - Find a platform device with a given
1364 * driver.
1365 * @start: The device to start the search from.
1366 * @drv: The device driver to look for.
1367 */
1368struct device *platform_find_device_by_driver(struct device *start,
1369					      const struct device_driver *drv)
1370{
1371	return bus_find_device(&platform_bus_type, start, drv,
1372			       __platform_match);
1373}
1374EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1375
1376void __weak __init early_platform_cleanup(void) { }
1377
1378int __init platform_bus_init(void)
1379{
1380	int error;
1381
1382	early_platform_cleanup();
1383
1384	error = device_register(&platform_bus);
1385	if (error) {
1386		put_device(&platform_bus);
1387		return error;
1388	}
1389	error =  bus_register(&platform_bus_type);
1390	if (error)
1391		device_unregister(&platform_bus);
1392	of_platform_register_reconfig_notifier();
1393	return error;
1394}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * platform.c - platform 'pseudo' bus for legacy devices
   4 *
   5 * Copyright (c) 2002-3 Patrick Mochel
   6 * Copyright (c) 2002-3 Open Source Development Labs
   7 *
   8 * Please see Documentation/driver-api/driver-model/platform.rst for more
   9 * information.
  10 */
  11
  12#include <linux/string.h>
  13#include <linux/platform_device.h>
  14#include <linux/of_device.h>
  15#include <linux/of_irq.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/interrupt.h>
  19#include <linux/ioport.h>
  20#include <linux/dma-mapping.h>
  21#include <linux/memblock.h>
  22#include <linux/err.h>
  23#include <linux/slab.h>
  24#include <linux/pm_runtime.h>
  25#include <linux/pm_domain.h>
  26#include <linux/idr.h>
  27#include <linux/acpi.h>
  28#include <linux/clk/clk-conf.h>
  29#include <linux/limits.h>
  30#include <linux/property.h>
  31#include <linux/kmemleak.h>
  32#include <linux/types.h>
  33
  34#include "base.h"
  35#include "power/power.h"
  36
  37/* For automatically allocated device IDs */
  38static DEFINE_IDA(platform_devid_ida);
  39
  40struct device platform_bus = {
  41	.init_name	= "platform",
  42};
  43EXPORT_SYMBOL_GPL(platform_bus);
  44
  45/**
  46 * platform_get_resource - get a resource for a device
  47 * @dev: platform device
  48 * @type: resource type
  49 * @num: resource index
  50 *
  51 * Return: a pointer to the resource or NULL on failure.
  52 */
  53struct resource *platform_get_resource(struct platform_device *dev,
  54				       unsigned int type, unsigned int num)
  55{
  56	u32 i;
  57
  58	for (i = 0; i < dev->num_resources; i++) {
  59		struct resource *r = &dev->resource[i];
  60
  61		if (type == resource_type(r) && num-- == 0)
  62			return r;
  63	}
  64	return NULL;
  65}
  66EXPORT_SYMBOL_GPL(platform_get_resource);
  67
  68struct resource *platform_get_mem_or_io(struct platform_device *dev,
  69					unsigned int num)
  70{
  71	u32 i;
  72
  73	for (i = 0; i < dev->num_resources; i++) {
  74		struct resource *r = &dev->resource[i];
  75
  76		if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
  77			return r;
  78	}
  79	return NULL;
  80}
  81EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
  82
  83#ifdef CONFIG_HAS_IOMEM
  84/**
  85 * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
  86 *					    platform device and get resource
  87 *
  88 * @pdev: platform device to use both for memory resource lookup as well as
  89 *        resource management
  90 * @index: resource index
  91 * @res: optional output parameter to store a pointer to the obtained resource.
  92 *
  93 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
  94 * on failure.
  95 */
  96void __iomem *
  97devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
  98				unsigned int index, struct resource **res)
  99{
 100	struct resource *r;
 101
 102	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
 103	if (res)
 104		*res = r;
 105	return devm_ioremap_resource(&pdev->dev, r);
 106}
 107EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
 108
 109/**
 110 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
 111 *				    device
 112 *
 113 * @pdev: platform device to use both for memory resource lookup as well as
 114 *        resource management
 115 * @index: resource index
 116 *
 117 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 118 * on failure.
 119 */
 120void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 121					     unsigned int index)
 122{
 123	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
 124}
 125EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
 126
 127/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 128 * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
 129 *					   a platform device, retrieve the
 130 *					   resource by name
 131 *
 132 * @pdev: platform device to use both for memory resource lookup as well as
 133 *	  resource management
 134 * @name: name of the resource
 135 *
 136 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 137 * on failure.
 138 */
 139void __iomem *
 140devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 141				      const char *name)
 142{
 143	struct resource *res;
 144
 145	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 146	return devm_ioremap_resource(&pdev->dev, res);
 147}
 148EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
 149#endif /* CONFIG_HAS_IOMEM */
 150
 151/**
 152 * platform_get_irq_optional - get an optional IRQ for a device
 153 * @dev: platform device
 154 * @num: IRQ number index
 155 *
 156 * Gets an IRQ for a platform device. Device drivers should check the return
 157 * value for errors so as to not pass a negative integer value to the
 158 * request_irq() APIs. This is the same as platform_get_irq(), except that it
 159 * does not print an error message if an IRQ can not be obtained.
 160 *
 161 * For example::
 162 *
 163 *		int irq = platform_get_irq_optional(pdev, 0);
 164 *		if (irq < 0)
 165 *			return irq;
 166 *
 167 * Return: non-zero IRQ number on success, negative error number on failure.
 168 */
 169int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 170{
 171	int ret;
 172#ifdef CONFIG_SPARC
 173	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
 174	if (!dev || num >= dev->archdata.num_irqs)
 175		goto out_not_found;
 176	ret = dev->archdata.irqs[num];
 177	goto out;
 178#else
 179	struct resource *r;
 180
 181	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 182		ret = of_irq_get(dev->dev.of_node, num);
 183		if (ret > 0 || ret == -EPROBE_DEFER)
 184			goto out;
 185	}
 186
 187	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 188	if (has_acpi_companion(&dev->dev)) {
 189		if (r && r->flags & IORESOURCE_DISABLED) {
 190			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 191			if (ret)
 192				goto out;
 193		}
 194	}
 195
 196	/*
 197	 * The resources may pass trigger flags to the irqs that need
 198	 * to be set up. It so happens that the trigger flags for
 199	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 200	 * settings.
 201	 */
 202	if (r && r->flags & IORESOURCE_BITS) {
 203		struct irq_data *irqd;
 204
 205		irqd = irq_get_irq_data(r->start);
 206		if (!irqd)
 207			goto out_not_found;
 
 
 208		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 209	}
 210
 211	if (r) {
 212		ret = r->start;
 213		goto out;
 214	}
 215
 216	/*
 217	 * For the index 0 interrupt, allow falling back to GpioInt
 218	 * resources. While a device could have both Interrupt and GpioInt
 219	 * resources, making this fallback ambiguous, in many common cases
 220	 * the device will only expose one IRQ, and this fallback
 221	 * allows a common code path across either kind of resource.
 222	 */
 223	if (num == 0 && has_acpi_companion(&dev->dev)) {
 224		ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
 225		/* Our callers expect -ENXIO for missing IRQs. */
 226		if (ret >= 0 || ret == -EPROBE_DEFER)
 227			goto out;
 228	}
 229
 
 230#endif
 231out_not_found:
 232	ret = -ENXIO;
 233out:
 234	WARN(ret == 0, "0 is an invalid IRQ number\n");
 235	return ret;
 236}
 237EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 238
 239/**
 240 * platform_get_irq - get an IRQ for a device
 241 * @dev: platform device
 242 * @num: IRQ number index
 243 *
 244 * Gets an IRQ for a platform device and prints an error message if finding the
 245 * IRQ fails. Device drivers should check the return value for errors so as to
 246 * not pass a negative integer value to the request_irq() APIs.
 247 *
 248 * For example::
 249 *
 250 *		int irq = platform_get_irq(pdev, 0);
 251 *		if (irq < 0)
 252 *			return irq;
 253 *
 254 * Return: non-zero IRQ number on success, negative error number on failure.
 255 */
 256int platform_get_irq(struct platform_device *dev, unsigned int num)
 257{
 258	int ret;
 259
 260	ret = platform_get_irq_optional(dev, num);
 261	if (ret < 0 && ret != -EPROBE_DEFER)
 262		dev_err(&dev->dev, "IRQ index %u not found\n", num);
 263
 264	return ret;
 265}
 266EXPORT_SYMBOL_GPL(platform_get_irq);
 267
 268/**
 269 * platform_irq_count - Count the number of IRQs a platform device uses
 270 * @dev: platform device
 271 *
 272 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 273 */
 274int platform_irq_count(struct platform_device *dev)
 275{
 276	int ret, nr = 0;
 277
 278	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
 279		nr++;
 280
 281	if (ret == -EPROBE_DEFER)
 282		return ret;
 283
 284	return nr;
 285}
 286EXPORT_SYMBOL_GPL(platform_irq_count);
 287
 288struct irq_affinity_devres {
 289	unsigned int count;
 290	unsigned int irq[];
 291};
 292
 293static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
 294{
 295	struct resource *r;
 296
 297	r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
 298	if (r)
 299		irqresource_disabled(r, 0);
 300}
 301
 302static void devm_platform_get_irqs_affinity_release(struct device *dev,
 303						    void *res)
 304{
 305	struct irq_affinity_devres *ptr = res;
 306	int i;
 307
 308	for (i = 0; i < ptr->count; i++) {
 309		irq_dispose_mapping(ptr->irq[i]);
 310
 311		if (has_acpi_companion(dev))
 312			platform_disable_acpi_irq(to_platform_device(dev), i);
 313	}
 314}
 315
 316/**
 317 * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
 318 *				device using an interrupt affinity descriptor
 319 * @dev: platform device pointer
 320 * @affd: affinity descriptor
 321 * @minvec: minimum count of interrupt vectors
 322 * @maxvec: maximum count of interrupt vectors
 323 * @irqs: pointer holder for IRQ numbers
 324 *
 325 * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
 326 * to the passed affinity descriptor
 327 *
 328 * Return: Number of vectors on success, negative error number on failure.
 329 */
 330int devm_platform_get_irqs_affinity(struct platform_device *dev,
 331				    struct irq_affinity *affd,
 332				    unsigned int minvec,
 333				    unsigned int maxvec,
 334				    int **irqs)
 335{
 336	struct irq_affinity_devres *ptr;
 337	struct irq_affinity_desc *desc;
 338	size_t size;
 339	int i, ret, nvec;
 340
 341	if (!affd)
 342		return -EPERM;
 343
 344	if (maxvec < minvec)
 345		return -ERANGE;
 346
 347	nvec = platform_irq_count(dev);
 348	if (nvec < 0)
 349		return nvec;
 350
 351	if (nvec < minvec)
 352		return -ENOSPC;
 353
 354	nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
 355	if (nvec < minvec)
 356		return -ENOSPC;
 357
 358	if (nvec > maxvec)
 359		nvec = maxvec;
 360
 361	size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
 362	ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
 363			   GFP_KERNEL);
 364	if (!ptr)
 365		return -ENOMEM;
 366
 367	ptr->count = nvec;
 368
 369	for (i = 0; i < nvec; i++) {
 370		int irq = platform_get_irq(dev, i);
 371		if (irq < 0) {
 372			ret = irq;
 373			goto err_free_devres;
 374		}
 375		ptr->irq[i] = irq;
 376	}
 377
 378	desc = irq_create_affinity_masks(nvec, affd);
 379	if (!desc) {
 380		ret = -ENOMEM;
 381		goto err_free_devres;
 382	}
 383
 384	for (i = 0; i < nvec; i++) {
 385		ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
 386		if (ret) {
 387			dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
 388				ptr->irq[i], ret);
 389			goto err_free_desc;
 390		}
 391	}
 392
 393	devres_add(&dev->dev, ptr);
 394
 395	kfree(desc);
 396
 397	*irqs = ptr->irq;
 398
 399	return nvec;
 400
 401err_free_desc:
 402	kfree(desc);
 403err_free_devres:
 404	devres_free(ptr);
 405	return ret;
 406}
 407EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
 408
 409/**
 410 * platform_get_resource_byname - get a resource for a device by name
 411 * @dev: platform device
 412 * @type: resource type
 413 * @name: resource name
 414 */
 415struct resource *platform_get_resource_byname(struct platform_device *dev,
 416					      unsigned int type,
 417					      const char *name)
 418{
 419	u32 i;
 420
 421	for (i = 0; i < dev->num_resources; i++) {
 422		struct resource *r = &dev->resource[i];
 423
 424		if (unlikely(!r->name))
 425			continue;
 426
 427		if (type == resource_type(r) && !strcmp(r->name, name))
 428			return r;
 429	}
 430	return NULL;
 431}
 432EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 433
 434static int __platform_get_irq_byname(struct platform_device *dev,
 435				     const char *name)
 436{
 437	struct resource *r;
 438	int ret;
 439
 440	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 441		ret = of_irq_get_byname(dev->dev.of_node, name);
 442		if (ret > 0 || ret == -EPROBE_DEFER)
 443			return ret;
 444	}
 445
 446	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 447	if (r) {
 448		WARN(r->start == 0, "0 is an invalid IRQ number\n");
 449		return r->start;
 450	}
 451
 452	return -ENXIO;
 453}
 454
 455/**
 456 * platform_get_irq_byname - get an IRQ for a device by name
 457 * @dev: platform device
 458 * @name: IRQ name
 459 *
 460 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
 461 *
 462 * Return: non-zero IRQ number on success, negative error number on failure.
 463 */
 464int platform_get_irq_byname(struct platform_device *dev, const char *name)
 465{
 466	int ret;
 467
 468	ret = __platform_get_irq_byname(dev, name);
 469	if (ret < 0 && ret != -EPROBE_DEFER)
 470		dev_err(&dev->dev, "IRQ %s not found\n", name);
 471
 472	return ret;
 473}
 474EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 475
 476/**
 477 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
 478 * @dev: platform device
 479 * @name: IRQ name
 480 *
 481 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
 482 * does not print an error message if an IRQ can not be obtained.
 483 *
 484 * Return: non-zero IRQ number on success, negative error number on failure.
 485 */
 486int platform_get_irq_byname_optional(struct platform_device *dev,
 487				     const char *name)
 488{
 489	return __platform_get_irq_byname(dev, name);
 490}
 491EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
 492
 493/**
 494 * platform_add_devices - add a numbers of platform devices
 495 * @devs: array of platform devices to add
 496 * @num: number of platform devices in array
 497 */
 498int platform_add_devices(struct platform_device **devs, int num)
 499{
 500	int i, ret = 0;
 501
 502	for (i = 0; i < num; i++) {
 503		ret = platform_device_register(devs[i]);
 504		if (ret) {
 505			while (--i >= 0)
 506				platform_device_unregister(devs[i]);
 507			break;
 508		}
 509	}
 510
 511	return ret;
 512}
 513EXPORT_SYMBOL_GPL(platform_add_devices);
 514
 515struct platform_object {
 516	struct platform_device pdev;
 517	char name[];
 518};
 519
 520/*
 521 * Set up default DMA mask for platform devices if the they weren't
 522 * previously set by the architecture / DT.
 523 */
 524static void setup_pdev_dma_masks(struct platform_device *pdev)
 525{
 526	pdev->dev.dma_parms = &pdev->dma_parms;
 527
 528	if (!pdev->dev.coherent_dma_mask)
 529		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 530	if (!pdev->dev.dma_mask) {
 531		pdev->platform_dma_mask = DMA_BIT_MASK(32);
 532		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 533	}
 534};
 535
 536/**
 537 * platform_device_put - destroy a platform device
 538 * @pdev: platform device to free
 539 *
 540 * Free all memory associated with a platform device.  This function must
 541 * _only_ be externally called in error cases.  All other usage is a bug.
 542 */
 543void platform_device_put(struct platform_device *pdev)
 544{
 545	if (!IS_ERR_OR_NULL(pdev))
 546		put_device(&pdev->dev);
 547}
 548EXPORT_SYMBOL_GPL(platform_device_put);
 549
 550static void platform_device_release(struct device *dev)
 551{
 552	struct platform_object *pa = container_of(dev, struct platform_object,
 553						  pdev.dev);
 554
 555	of_node_put(pa->pdev.dev.of_node);
 556	kfree(pa->pdev.dev.platform_data);
 557	kfree(pa->pdev.mfd_cell);
 558	kfree(pa->pdev.resource);
 559	kfree(pa->pdev.driver_override);
 560	kfree(pa);
 561}
 562
 563/**
 564 * platform_device_alloc - create a platform device
 565 * @name: base name of the device we're adding
 566 * @id: instance id
 567 *
 568 * Create a platform device object which can have other objects attached
 569 * to it, and which will have attached objects freed when it is released.
 570 */
 571struct platform_device *platform_device_alloc(const char *name, int id)
 572{
 573	struct platform_object *pa;
 574
 575	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 576	if (pa) {
 577		strcpy(pa->name, name);
 578		pa->pdev.name = pa->name;
 579		pa->pdev.id = id;
 580		device_initialize(&pa->pdev.dev);
 581		pa->pdev.dev.release = platform_device_release;
 582		setup_pdev_dma_masks(&pa->pdev);
 583	}
 584
 585	return pa ? &pa->pdev : NULL;
 586}
 587EXPORT_SYMBOL_GPL(platform_device_alloc);
 588
 589/**
 590 * platform_device_add_resources - add resources to a platform device
 591 * @pdev: platform device allocated by platform_device_alloc to add resources to
 592 * @res: set of resources that needs to be allocated for the device
 593 * @num: number of resources
 594 *
 595 * Add a copy of the resources to the platform device.  The memory
 596 * associated with the resources will be freed when the platform device is
 597 * released.
 598 */
 599int platform_device_add_resources(struct platform_device *pdev,
 600				  const struct resource *res, unsigned int num)
 601{
 602	struct resource *r = NULL;
 603
 604	if (res) {
 605		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 606		if (!r)
 607			return -ENOMEM;
 608	}
 609
 610	kfree(pdev->resource);
 611	pdev->resource = r;
 612	pdev->num_resources = num;
 613	return 0;
 614}
 615EXPORT_SYMBOL_GPL(platform_device_add_resources);
 616
 617/**
 618 * platform_device_add_data - add platform-specific data to a platform device
 619 * @pdev: platform device allocated by platform_device_alloc to add resources to
 620 * @data: platform specific data for this platform device
 621 * @size: size of platform specific data
 622 *
 623 * Add a copy of platform specific data to the platform device's
 624 * platform_data pointer.  The memory associated with the platform data
 625 * will be freed when the platform device is released.
 626 */
 627int platform_device_add_data(struct platform_device *pdev, const void *data,
 628			     size_t size)
 629{
 630	void *d = NULL;
 631
 632	if (data) {
 633		d = kmemdup(data, size, GFP_KERNEL);
 634		if (!d)
 635			return -ENOMEM;
 636	}
 637
 638	kfree(pdev->dev.platform_data);
 639	pdev->dev.platform_data = d;
 640	return 0;
 641}
 642EXPORT_SYMBOL_GPL(platform_device_add_data);
 643
 644/**
 645 * platform_device_add_properties - add built-in properties to a platform device
 646 * @pdev: platform device to add properties to
 647 * @properties: null terminated array of properties to add
 648 *
 649 * The function will take deep copy of @properties and attach the copy to the
 650 * platform device. The memory associated with properties will be freed when the
 651 * platform device is released.
 652 */
 653int platform_device_add_properties(struct platform_device *pdev,
 654				   const struct property_entry *properties)
 655{
 656	return device_add_properties(&pdev->dev, properties);
 657}
 658EXPORT_SYMBOL_GPL(platform_device_add_properties);
 659
 660/**
 661 * platform_device_add - add a platform device to device hierarchy
 662 * @pdev: platform device we're adding
 663 *
 664 * This is part 2 of platform_device_register(), though may be called
 665 * separately _iff_ pdev was allocated by platform_device_alloc().
 666 */
 667int platform_device_add(struct platform_device *pdev)
 668{
 669	u32 i;
 670	int ret;
 671
 672	if (!pdev)
 673		return -EINVAL;
 674
 675	if (!pdev->dev.parent)
 676		pdev->dev.parent = &platform_bus;
 677
 678	pdev->dev.bus = &platform_bus_type;
 679
 680	switch (pdev->id) {
 681	default:
 682		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 683		break;
 684	case PLATFORM_DEVID_NONE:
 685		dev_set_name(&pdev->dev, "%s", pdev->name);
 686		break;
 687	case PLATFORM_DEVID_AUTO:
 688		/*
 689		 * Automatically allocated device ID. We mark it as such so
 690		 * that we remember it must be freed, and we append a suffix
 691		 * to avoid namespace collision with explicit IDs.
 692		 */
 693		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
 694		if (ret < 0)
 695			goto err_out;
 696		pdev->id = ret;
 697		pdev->id_auto = true;
 698		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 699		break;
 700	}
 701
 702	for (i = 0; i < pdev->num_resources; i++) {
 703		struct resource *p, *r = &pdev->resource[i];
 704
 705		if (r->name == NULL)
 706			r->name = dev_name(&pdev->dev);
 707
 708		p = r->parent;
 709		if (!p) {
 710			if (resource_type(r) == IORESOURCE_MEM)
 711				p = &iomem_resource;
 712			else if (resource_type(r) == IORESOURCE_IO)
 713				p = &ioport_resource;
 714		}
 715
 716		if (p) {
 717			ret = insert_resource(p, r);
 718			if (ret) {
 719				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 720				goto failed;
 721			}
 722		}
 723	}
 724
 725	pr_debug("Registering platform device '%s'. Parent at %s\n",
 726		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 727
 728	ret = device_add(&pdev->dev);
 729	if (ret == 0)
 730		return ret;
 731
 732 failed:
 733	if (pdev->id_auto) {
 734		ida_free(&platform_devid_ida, pdev->id);
 735		pdev->id = PLATFORM_DEVID_AUTO;
 736	}
 737
 738	while (i--) {
 739		struct resource *r = &pdev->resource[i];
 740		if (r->parent)
 741			release_resource(r);
 742	}
 743
 744 err_out:
 745	return ret;
 746}
 747EXPORT_SYMBOL_GPL(platform_device_add);
 748
 749/**
 750 * platform_device_del - remove a platform-level device
 751 * @pdev: platform device we're removing
 752 *
 753 * Note that this function will also release all memory- and port-based
 754 * resources owned by the device (@dev->resource).  This function must
 755 * _only_ be externally called in error cases.  All other usage is a bug.
 756 */
 757void platform_device_del(struct platform_device *pdev)
 758{
 759	u32 i;
 760
 761	if (!IS_ERR_OR_NULL(pdev)) {
 762		device_del(&pdev->dev);
 763
 764		if (pdev->id_auto) {
 765			ida_free(&platform_devid_ida, pdev->id);
 766			pdev->id = PLATFORM_DEVID_AUTO;
 767		}
 768
 769		for (i = 0; i < pdev->num_resources; i++) {
 770			struct resource *r = &pdev->resource[i];
 771			if (r->parent)
 772				release_resource(r);
 773		}
 774	}
 775}
 776EXPORT_SYMBOL_GPL(platform_device_del);
 777
 778/**
 779 * platform_device_register - add a platform-level device
 780 * @pdev: platform device we're adding
 781 */
 782int platform_device_register(struct platform_device *pdev)
 783{
 784	device_initialize(&pdev->dev);
 785	setup_pdev_dma_masks(pdev);
 786	return platform_device_add(pdev);
 787}
 788EXPORT_SYMBOL_GPL(platform_device_register);
 789
 790/**
 791 * platform_device_unregister - unregister a platform-level device
 792 * @pdev: platform device we're unregistering
 793 *
 794 * Unregistration is done in 2 steps. First we release all resources
 795 * and remove it from the subsystem, then we drop reference count by
 796 * calling platform_device_put().
 797 */
 798void platform_device_unregister(struct platform_device *pdev)
 799{
 800	platform_device_del(pdev);
 801	platform_device_put(pdev);
 802}
 803EXPORT_SYMBOL_GPL(platform_device_unregister);
 804
 805/**
 806 * platform_device_register_full - add a platform-level device with
 807 * resources and platform-specific data
 808 *
 809 * @pdevinfo: data used to create device
 810 *
 811 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 812 */
 813struct platform_device *platform_device_register_full(
 814		const struct platform_device_info *pdevinfo)
 815{
 816	int ret;
 817	struct platform_device *pdev;
 818
 819	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 820	if (!pdev)
 821		return ERR_PTR(-ENOMEM);
 822
 823	pdev->dev.parent = pdevinfo->parent;
 824	pdev->dev.fwnode = pdevinfo->fwnode;
 825	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
 826	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
 827
 828	if (pdevinfo->dma_mask) {
 829		pdev->platform_dma_mask = pdevinfo->dma_mask;
 830		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 831		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 832	}
 833
 834	ret = platform_device_add_resources(pdev,
 835			pdevinfo->res, pdevinfo->num_res);
 836	if (ret)
 837		goto err;
 838
 839	ret = platform_device_add_data(pdev,
 840			pdevinfo->data, pdevinfo->size_data);
 841	if (ret)
 842		goto err;
 843
 844	if (pdevinfo->properties) {
 845		ret = platform_device_add_properties(pdev,
 846						     pdevinfo->properties);
 847		if (ret)
 848			goto err;
 849	}
 850
 851	ret = platform_device_add(pdev);
 852	if (ret) {
 853err:
 854		ACPI_COMPANION_SET(&pdev->dev, NULL);
 855		platform_device_put(pdev);
 856		return ERR_PTR(ret);
 857	}
 858
 859	return pdev;
 860}
 861EXPORT_SYMBOL_GPL(platform_device_register_full);
 862
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 863/**
 864 * __platform_driver_register - register a driver for platform-level devices
 865 * @drv: platform driver structure
 866 * @owner: owning module/driver
 867 */
 868int __platform_driver_register(struct platform_driver *drv,
 869				struct module *owner)
 870{
 871	drv->driver.owner = owner;
 872	drv->driver.bus = &platform_bus_type;
 
 
 
 873
 874	return driver_register(&drv->driver);
 875}
 876EXPORT_SYMBOL_GPL(__platform_driver_register);
 877
 878/**
 879 * platform_driver_unregister - unregister a driver for platform-level devices
 880 * @drv: platform driver structure
 881 */
 882void platform_driver_unregister(struct platform_driver *drv)
 883{
 884	driver_unregister(&drv->driver);
 885}
 886EXPORT_SYMBOL_GPL(platform_driver_unregister);
 887
 888static int platform_probe_fail(struct platform_device *pdev)
 889{
 890	return -ENXIO;
 891}
 892
 893/**
 894 * __platform_driver_probe - register driver for non-hotpluggable device
 895 * @drv: platform driver structure
 896 * @probe: the driver probe routine, probably from an __init section
 897 * @module: module which will be the owner of the driver
 898 *
 899 * Use this instead of platform_driver_register() when you know the device
 900 * is not hotpluggable and has already been registered, and you want to
 901 * remove its run-once probe() infrastructure from memory after the driver
 902 * has bound to the device.
 903 *
 904 * One typical use for this would be with drivers for controllers integrated
 905 * into system-on-chip processors, where the controller devices have been
 906 * configured as part of board setup.
 907 *
 908 * Note that this is incompatible with deferred probing.
 909 *
 910 * Returns zero if the driver registered and bound to a device, else returns
 911 * a negative error code and with the driver not registered.
 912 */
 913int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 914		int (*probe)(struct platform_device *), struct module *module)
 915{
 916	int retval, code;
 917
 918	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 919		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 920			 drv->driver.name, __func__);
 921		return -EINVAL;
 922	}
 923
 924	/*
 925	 * We have to run our probes synchronously because we check if
 926	 * we find any devices to bind to and exit with error if there
 927	 * are any.
 928	 */
 929	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 930
 931	/*
 932	 * Prevent driver from requesting probe deferral to avoid further
 933	 * futile probe attempts.
 934	 */
 935	drv->prevent_deferred_probe = true;
 936
 937	/* make sure driver won't have bind/unbind attributes */
 938	drv->driver.suppress_bind_attrs = true;
 939
 940	/* temporary section violation during probe() */
 941	drv->probe = probe;
 942	retval = code = __platform_driver_register(drv, module);
 943	if (retval)
 944		return retval;
 945
 946	/*
 947	 * Fixup that section violation, being paranoid about code scanning
 948	 * the list of drivers in order to probe new devices.  Check to see
 949	 * if the probe was successful, and make sure any forced probes of
 950	 * new devices fail.
 951	 */
 952	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 953	drv->probe = platform_probe_fail;
 954	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 955		retval = -ENODEV;
 
 956	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 957
 958	if (code != retval)
 959		platform_driver_unregister(drv);
 960	return retval;
 961}
 962EXPORT_SYMBOL_GPL(__platform_driver_probe);
 963
 964/**
 965 * __platform_create_bundle - register driver and create corresponding device
 966 * @driver: platform driver structure
 967 * @probe: the driver probe routine, probably from an __init section
 968 * @res: set of resources that needs to be allocated for the device
 969 * @n_res: number of resources
 970 * @data: platform specific data for this platform device
 971 * @size: size of platform specific data
 972 * @module: module which will be the owner of the driver
 973 *
 974 * Use this in legacy-style modules that probe hardware directly and
 975 * register a single platform device and corresponding platform driver.
 976 *
 977 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 978 */
 979struct platform_device * __init_or_module __platform_create_bundle(
 980			struct platform_driver *driver,
 981			int (*probe)(struct platform_device *),
 982			struct resource *res, unsigned int n_res,
 983			const void *data, size_t size, struct module *module)
 984{
 985	struct platform_device *pdev;
 986	int error;
 987
 988	pdev = platform_device_alloc(driver->driver.name, -1);
 989	if (!pdev) {
 990		error = -ENOMEM;
 991		goto err_out;
 992	}
 993
 994	error = platform_device_add_resources(pdev, res, n_res);
 995	if (error)
 996		goto err_pdev_put;
 997
 998	error = platform_device_add_data(pdev, data, size);
 999	if (error)
1000		goto err_pdev_put;
1001
1002	error = platform_device_add(pdev);
1003	if (error)
1004		goto err_pdev_put;
1005
1006	error = __platform_driver_probe(driver, probe, module);
1007	if (error)
1008		goto err_pdev_del;
1009
1010	return pdev;
1011
1012err_pdev_del:
1013	platform_device_del(pdev);
1014err_pdev_put:
1015	platform_device_put(pdev);
1016err_out:
1017	return ERR_PTR(error);
1018}
1019EXPORT_SYMBOL_GPL(__platform_create_bundle);
1020
1021/**
1022 * __platform_register_drivers - register an array of platform drivers
1023 * @drivers: an array of drivers to register
1024 * @count: the number of drivers to register
1025 * @owner: module owning the drivers
1026 *
1027 * Registers platform drivers specified by an array. On failure to register a
1028 * driver, all previously registered drivers will be unregistered. Callers of
1029 * this API should use platform_unregister_drivers() to unregister drivers in
1030 * the reverse order.
1031 *
1032 * Returns: 0 on success or a negative error code on failure.
1033 */
1034int __platform_register_drivers(struct platform_driver * const *drivers,
1035				unsigned int count, struct module *owner)
1036{
1037	unsigned int i;
1038	int err;
1039
1040	for (i = 0; i < count; i++) {
1041		pr_debug("registering platform driver %ps\n", drivers[i]);
1042
1043		err = __platform_driver_register(drivers[i], owner);
1044		if (err < 0) {
1045			pr_err("failed to register platform driver %ps: %d\n",
1046			       drivers[i], err);
1047			goto error;
1048		}
1049	}
1050
1051	return 0;
1052
1053error:
1054	while (i--) {
1055		pr_debug("unregistering platform driver %ps\n", drivers[i]);
1056		platform_driver_unregister(drivers[i]);
1057	}
1058
1059	return err;
1060}
1061EXPORT_SYMBOL_GPL(__platform_register_drivers);
1062
1063/**
1064 * platform_unregister_drivers - unregister an array of platform drivers
1065 * @drivers: an array of drivers to unregister
1066 * @count: the number of drivers to unregister
1067 *
1068 * Unregisters platform drivers specified by an array. This is typically used
1069 * to complement an earlier call to platform_register_drivers(). Drivers are
1070 * unregistered in the reverse order in which they were registered.
1071 */
1072void platform_unregister_drivers(struct platform_driver * const *drivers,
1073				 unsigned int count)
1074{
1075	while (count--) {
1076		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1077		platform_driver_unregister(drivers[count]);
1078	}
1079}
1080EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1081
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1082static const struct platform_device_id *platform_match_id(
1083			const struct platform_device_id *id,
1084			struct platform_device *pdev)
1085{
1086	while (id->name[0]) {
1087		if (strcmp(pdev->name, id->name) == 0) {
1088			pdev->id_entry = id;
1089			return id;
1090		}
1091		id++;
1092	}
1093	return NULL;
1094}
1095
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1096#ifdef CONFIG_PM_SLEEP
1097
1098static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1099{
1100	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1101	struct platform_device *pdev = to_platform_device(dev);
1102	int ret = 0;
1103
1104	if (dev->driver && pdrv->suspend)
1105		ret = pdrv->suspend(pdev, mesg);
1106
1107	return ret;
1108}
1109
1110static int platform_legacy_resume(struct device *dev)
1111{
1112	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1113	struct platform_device *pdev = to_platform_device(dev);
1114	int ret = 0;
1115
1116	if (dev->driver && pdrv->resume)
1117		ret = pdrv->resume(pdev);
1118
1119	return ret;
1120}
1121
1122#endif /* CONFIG_PM_SLEEP */
1123
1124#ifdef CONFIG_SUSPEND
1125
1126int platform_pm_suspend(struct device *dev)
1127{
1128	struct device_driver *drv = dev->driver;
1129	int ret = 0;
1130
1131	if (!drv)
1132		return 0;
1133
1134	if (drv->pm) {
1135		if (drv->pm->suspend)
1136			ret = drv->pm->suspend(dev);
1137	} else {
1138		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1139	}
1140
1141	return ret;
1142}
1143
1144int platform_pm_resume(struct device *dev)
1145{
1146	struct device_driver *drv = dev->driver;
1147	int ret = 0;
1148
1149	if (!drv)
1150		return 0;
1151
1152	if (drv->pm) {
1153		if (drv->pm->resume)
1154			ret = drv->pm->resume(dev);
1155	} else {
1156		ret = platform_legacy_resume(dev);
1157	}
1158
1159	return ret;
1160}
1161
1162#endif /* CONFIG_SUSPEND */
1163
1164#ifdef CONFIG_HIBERNATE_CALLBACKS
1165
1166int platform_pm_freeze(struct device *dev)
1167{
1168	struct device_driver *drv = dev->driver;
1169	int ret = 0;
1170
1171	if (!drv)
1172		return 0;
1173
1174	if (drv->pm) {
1175		if (drv->pm->freeze)
1176			ret = drv->pm->freeze(dev);
1177	} else {
1178		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1179	}
1180
1181	return ret;
1182}
1183
1184int platform_pm_thaw(struct device *dev)
1185{
1186	struct device_driver *drv = dev->driver;
1187	int ret = 0;
1188
1189	if (!drv)
1190		return 0;
1191
1192	if (drv->pm) {
1193		if (drv->pm->thaw)
1194			ret = drv->pm->thaw(dev);
1195	} else {
1196		ret = platform_legacy_resume(dev);
1197	}
1198
1199	return ret;
1200}
1201
1202int platform_pm_poweroff(struct device *dev)
1203{
1204	struct device_driver *drv = dev->driver;
1205	int ret = 0;
1206
1207	if (!drv)
1208		return 0;
1209
1210	if (drv->pm) {
1211		if (drv->pm->poweroff)
1212			ret = drv->pm->poweroff(dev);
1213	} else {
1214		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1215	}
1216
1217	return ret;
1218}
1219
1220int platform_pm_restore(struct device *dev)
1221{
1222	struct device_driver *drv = dev->driver;
1223	int ret = 0;
1224
1225	if (!drv)
1226		return 0;
1227
1228	if (drv->pm) {
1229		if (drv->pm->restore)
1230			ret = drv->pm->restore(dev);
1231	} else {
1232		ret = platform_legacy_resume(dev);
1233	}
1234
1235	return ret;
1236}
1237
1238#endif /* CONFIG_HIBERNATE_CALLBACKS */
1239
1240/* modalias support enables more hands-off userspace setup:
1241 * (a) environment variable lets new-style hotplug events work once system is
1242 *     fully running:  "modprobe $MODALIAS"
1243 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1244 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1245 */
1246static ssize_t modalias_show(struct device *dev,
1247			     struct device_attribute *attr, char *buf)
1248{
1249	struct platform_device *pdev = to_platform_device(dev);
1250	int len;
1251
1252	len = of_device_modalias(dev, buf, PAGE_SIZE);
1253	if (len != -ENODEV)
1254		return len;
1255
1256	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1257	if (len != -ENODEV)
1258		return len;
1259
1260	return sysfs_emit(buf, "platform:%s\n", pdev->name);
1261}
1262static DEVICE_ATTR_RO(modalias);
1263
1264static ssize_t numa_node_show(struct device *dev,
1265			      struct device_attribute *attr, char *buf)
1266{
1267	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1268}
1269static DEVICE_ATTR_RO(numa_node);
1270
1271static ssize_t driver_override_show(struct device *dev,
1272				    struct device_attribute *attr, char *buf)
1273{
1274	struct platform_device *pdev = to_platform_device(dev);
1275	ssize_t len;
1276
1277	device_lock(dev);
1278	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1279	device_unlock(dev);
1280
1281	return len;
1282}
1283
1284static ssize_t driver_override_store(struct device *dev,
1285				     struct device_attribute *attr,
1286				     const char *buf, size_t count)
1287{
1288	struct platform_device *pdev = to_platform_device(dev);
1289	char *driver_override, *old, *cp;
1290
1291	/* We need to keep extra room for a newline */
1292	if (count >= (PAGE_SIZE - 1))
1293		return -EINVAL;
1294
1295	driver_override = kstrndup(buf, count, GFP_KERNEL);
1296	if (!driver_override)
1297		return -ENOMEM;
1298
1299	cp = strchr(driver_override, '\n');
1300	if (cp)
1301		*cp = '\0';
1302
1303	device_lock(dev);
1304	old = pdev->driver_override;
1305	if (strlen(driver_override)) {
1306		pdev->driver_override = driver_override;
1307	} else {
1308		kfree(driver_override);
1309		pdev->driver_override = NULL;
1310	}
1311	device_unlock(dev);
1312
1313	kfree(old);
1314
1315	return count;
1316}
1317static DEVICE_ATTR_RW(driver_override);
1318
1319static struct attribute *platform_dev_attrs[] = {
1320	&dev_attr_modalias.attr,
1321	&dev_attr_numa_node.attr,
1322	&dev_attr_driver_override.attr,
1323	NULL,
1324};
1325
1326static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1327		int n)
1328{
1329	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1330
1331	if (a == &dev_attr_numa_node.attr &&
1332			dev_to_node(dev) == NUMA_NO_NODE)
1333		return 0;
1334
1335	return a->mode;
1336}
1337
1338static const struct attribute_group platform_dev_group = {
1339	.attrs = platform_dev_attrs,
1340	.is_visible = platform_dev_attrs_visible,
1341};
1342__ATTRIBUTE_GROUPS(platform_dev);
1343
1344
1345/**
1346 * platform_match - bind platform device to platform driver.
1347 * @dev: device.
1348 * @drv: driver.
1349 *
1350 * Platform device IDs are assumed to be encoded like this:
1351 * "<name><instance>", where <name> is a short description of the type of
1352 * device, like "pci" or "floppy", and <instance> is the enumerated
1353 * instance of the device, like '0' or '42'.  Driver IDs are simply
1354 * "<name>".  So, extract the <name> from the platform_device structure,
1355 * and compare it against the name of the driver. Return whether they match
1356 * or not.
1357 */
1358static int platform_match(struct device *dev, struct device_driver *drv)
1359{
1360	struct platform_device *pdev = to_platform_device(dev);
1361	struct platform_driver *pdrv = to_platform_driver(drv);
1362
1363	/* When driver_override is set, only bind to the matching driver */
1364	if (pdev->driver_override)
1365		return !strcmp(pdev->driver_override, drv->name);
1366
1367	/* Attempt an OF style match first */
1368	if (of_driver_match_device(dev, drv))
1369		return 1;
1370
1371	/* Then try ACPI style match */
1372	if (acpi_driver_match_device(dev, drv))
1373		return 1;
1374
1375	/* Then try to match against the id table */
1376	if (pdrv->id_table)
1377		return platform_match_id(pdrv->id_table, pdev) != NULL;
1378
1379	/* fall-back to driver name match */
1380	return (strcmp(pdev->name, drv->name) == 0);
1381}
1382
1383static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1384{
1385	struct platform_device	*pdev = to_platform_device(dev);
1386	int rc;
1387
1388	/* Some devices have extra OF data and an OF-style MODALIAS */
1389	rc = of_device_uevent_modalias(dev, env);
1390	if (rc != -ENODEV)
1391		return rc;
1392
1393	rc = acpi_device_uevent_modalias(dev, env);
1394	if (rc != -ENODEV)
1395		return rc;
1396
1397	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1398			pdev->name);
1399	return 0;
1400}
1401
1402static int platform_probe(struct device *_dev)
1403{
1404	struct platform_driver *drv = to_platform_driver(_dev->driver);
1405	struct platform_device *dev = to_platform_device(_dev);
1406	int ret;
1407
1408	/*
1409	 * A driver registered using platform_driver_probe() cannot be bound
1410	 * again later because the probe function usually lives in __init code
1411	 * and so is gone. For these drivers .probe is set to
1412	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1413	 * clocks and PM domains for these to match the traditional behaviour.
1414	 */
1415	if (unlikely(drv->probe == platform_probe_fail))
1416		return -ENXIO;
1417
1418	ret = of_clk_set_defaults(_dev->of_node, false);
1419	if (ret < 0)
1420		return ret;
1421
1422	ret = dev_pm_domain_attach(_dev, true);
1423	if (ret)
1424		goto out;
1425
1426	if (drv->probe) {
1427		ret = drv->probe(dev);
1428		if (ret)
1429			dev_pm_domain_detach(_dev, true);
1430	}
1431
1432out:
1433	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1434		dev_warn(_dev, "probe deferral not supported\n");
1435		ret = -ENXIO;
1436	}
1437
1438	return ret;
1439}
1440
1441static int platform_remove(struct device *_dev)
1442{
1443	struct platform_driver *drv = to_platform_driver(_dev->driver);
1444	struct platform_device *dev = to_platform_device(_dev);
1445
1446	if (drv->remove) {
1447		int ret = drv->remove(dev);
1448
1449		if (ret)
1450			dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1451	}
1452	dev_pm_domain_detach(_dev, true);
1453
1454	return 0;
1455}
1456
1457static void platform_shutdown(struct device *_dev)
1458{
1459	struct platform_device *dev = to_platform_device(_dev);
1460	struct platform_driver *drv;
1461
1462	if (!_dev->driver)
1463		return;
1464
1465	drv = to_platform_driver(_dev->driver);
1466	if (drv->shutdown)
1467		drv->shutdown(dev);
1468}
1469
1470
1471int platform_dma_configure(struct device *dev)
1472{
1473	enum dev_dma_attr attr;
1474	int ret = 0;
1475
1476	if (dev->of_node) {
1477		ret = of_dma_configure(dev, dev->of_node, true);
1478	} else if (has_acpi_companion(dev)) {
1479		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1480		ret = acpi_dma_configure(dev, attr);
1481	}
1482
1483	return ret;
1484}
1485
1486static const struct dev_pm_ops platform_dev_pm_ops = {
1487	.runtime_suspend = pm_generic_runtime_suspend,
1488	.runtime_resume = pm_generic_runtime_resume,
1489	USE_PLATFORM_PM_SLEEP_OPS
1490};
1491
1492struct bus_type platform_bus_type = {
1493	.name		= "platform",
1494	.dev_groups	= platform_dev_groups,
1495	.match		= platform_match,
1496	.uevent		= platform_uevent,
1497	.probe		= platform_probe,
1498	.remove		= platform_remove,
1499	.shutdown	= platform_shutdown,
1500	.dma_configure	= platform_dma_configure,
1501	.pm		= &platform_dev_pm_ops,
1502};
1503EXPORT_SYMBOL_GPL(platform_bus_type);
1504
1505static inline int __platform_match(struct device *dev, const void *drv)
1506{
1507	return platform_match(dev, (struct device_driver *)drv);
1508}
1509
1510/**
1511 * platform_find_device_by_driver - Find a platform device with a given
1512 * driver.
1513 * @start: The device to start the search from.
1514 * @drv: The device driver to look for.
1515 */
1516struct device *platform_find_device_by_driver(struct device *start,
1517					      const struct device_driver *drv)
1518{
1519	return bus_find_device(&platform_bus_type, start, drv,
1520			       __platform_match);
1521}
1522EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1523
1524void __weak __init early_platform_cleanup(void) { }
1525
1526int __init platform_bus_init(void)
1527{
1528	int error;
1529
1530	early_platform_cleanup();
1531
1532	error = device_register(&platform_bus);
1533	if (error) {
1534		put_device(&platform_bus);
1535		return error;
1536	}
1537	error =  bus_register(&platform_bus_type);
1538	if (error)
1539		device_unregister(&platform_bus);
1540	of_platform_register_reconfig_notifier();
1541	return error;
1542}