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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}
v4.10.11
 
   1/*
   2 * platform.c - platform 'pseudo' bus for legacy devices
   3 *
   4 * Copyright (c) 2002-3 Patrick Mochel
   5 * Copyright (c) 2002-3 Open Source Development Labs
   6 *
   7 * This file is released under the GPLv2
   8 *
   9 * Please see Documentation/driver-model/platform.txt for more
  10 * information.
  11 */
  12
  13#include <linux/string.h>
  14#include <linux/platform_device.h>
  15#include <linux/of_device.h>
  16#include <linux/of_irq.h>
  17#include <linux/module.h>
  18#include <linux/init.h>
  19#include <linux/dma-mapping.h>
  20#include <linux/bootmem.h>
  21#include <linux/err.h>
  22#include <linux/slab.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/pm_domain.h>
  25#include <linux/idr.h>
  26#include <linux/acpi.h>
  27#include <linux/clk/clk-conf.h>
  28#include <linux/limits.h>
  29#include <linux/property.h>
 
 
  30
  31#include "base.h"
  32#include "power/power.h"
  33
  34/* For automatically allocated device IDs */
  35static DEFINE_IDA(platform_devid_ida);
  36
  37struct device platform_bus = {
  38	.init_name	= "platform",
  39};
  40EXPORT_SYMBOL_GPL(platform_bus);
  41
  42/**
  43 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  44 * @pdev: platform device
  45 *
  46 * This is called before platform_device_add() such that any pdev_archdata may
  47 * be setup before the platform_notifier is called.  So if a user needs to
  48 * manipulate any relevant information in the pdev_archdata they can do:
  49 *
  50 *	platform_device_alloc()
  51 *	... manipulate ...
  52 *	platform_device_add()
  53 *
  54 * And if they don't care they can just call platform_device_register() and
  55 * everything will just work out.
  56 */
  57void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  58{
  59}
  60
  61/**
  62 * platform_get_resource - get a resource for a device
  63 * @dev: platform device
  64 * @type: resource type
  65 * @num: resource index
  66 */
  67struct resource *platform_get_resource(struct platform_device *dev,
  68				       unsigned int type, unsigned int num)
  69{
  70	int i;
  71
  72	for (i = 0; i < dev->num_resources; i++) {
  73		struct resource *r = &dev->resource[i];
  74
  75		if (type == resource_type(r) && num-- == 0)
  76			return r;
  77	}
  78	return NULL;
  79}
  80EXPORT_SYMBOL_GPL(platform_get_resource);
  81
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  82/**
  83 * platform_get_irq - get an IRQ for a device
  84 * @dev: platform device
  85 * @num: IRQ number index
 
 
 
 
 
 
 
 
 
 
 
 
 
  86 */
  87int platform_get_irq(struct platform_device *dev, unsigned int num)
  88{
 
  89#ifdef CONFIG_SPARC
  90	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
  91	if (!dev || num >= dev->archdata.num_irqs)
  92		return -ENXIO;
  93	return dev->archdata.irqs[num];
 
  94#else
  95	struct resource *r;
 
  96	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
  97		int ret;
  98
  99		ret = of_irq_get(dev->dev.of_node, num);
 100		if (ret > 0 || ret == -EPROBE_DEFER)
 101			return ret;
 102	}
 103
 104	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 
 
 
 
 
 
 
 105	/*
 106	 * The resources may pass trigger flags to the irqs that need
 107	 * to be set up. It so happens that the trigger flags for
 108	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 109	 * settings.
 110	 */
 111	if (r && r->flags & IORESOURCE_BITS) {
 112		struct irq_data *irqd;
 113
 114		irqd = irq_get_irq_data(r->start);
 115		if (!irqd)
 116			return -ENXIO;
 
 
 117		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 118	}
 119
 120	return r ? r->start : -ENXIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 121#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 122}
 123EXPORT_SYMBOL_GPL(platform_get_irq);
 124
 125/**
 126 * platform_irq_count - Count the number of IRQs a platform device uses
 127 * @dev: platform device
 128 *
 129 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 130 */
 131int platform_irq_count(struct platform_device *dev)
 132{
 133	int ret, nr = 0;
 134
 135	while ((ret = platform_get_irq(dev, nr)) >= 0)
 136		nr++;
 137
 138	if (ret == -EPROBE_DEFER)
 139		return ret;
 140
 141	return nr;
 142}
 143EXPORT_SYMBOL_GPL(platform_irq_count);
 144
 145/**
 146 * platform_get_resource_byname - get a resource for a device by name
 147 * @dev: platform device
 148 * @type: resource type
 149 * @name: resource name
 150 */
 151struct resource *platform_get_resource_byname(struct platform_device *dev,
 152					      unsigned int type,
 153					      const char *name)
 154{
 155	int i;
 156
 157	for (i = 0; i < dev->num_resources; i++) {
 158		struct resource *r = &dev->resource[i];
 159
 160		if (unlikely(!r->name))
 161			continue;
 162
 163		if (type == resource_type(r) && !strcmp(r->name, name))
 164			return r;
 165	}
 166	return NULL;
 167}
 168EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 169
 170/**
 171 * platform_get_irq_byname - get an IRQ for a device by name
 172 * @dev: platform device
 173 * @name: IRQ name
 174 */
 175int platform_get_irq_byname(struct platform_device *dev, const char *name)
 176{
 177	struct resource *r;
 
 178
 179	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 180		int ret;
 181
 182		ret = of_irq_get_byname(dev->dev.of_node, name);
 183		if (ret > 0 || ret == -EPROBE_DEFER)
 184			return ret;
 185	}
 186
 187	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 188	return r ? r->start : -ENXIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 189}
 190EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 191
 192/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 193 * platform_add_devices - add a numbers of platform devices
 194 * @devs: array of platform devices to add
 195 * @num: number of platform devices in array
 196 */
 197int platform_add_devices(struct platform_device **devs, int num)
 198{
 199	int i, ret = 0;
 200
 201	for (i = 0; i < num; i++) {
 202		ret = platform_device_register(devs[i]);
 203		if (ret) {
 204			while (--i >= 0)
 205				platform_device_unregister(devs[i]);
 206			break;
 207		}
 208	}
 209
 210	return ret;
 211}
 212EXPORT_SYMBOL_GPL(platform_add_devices);
 213
 214struct platform_object {
 215	struct platform_device pdev;
 216	char name[];
 217};
 218
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 219/**
 220 * platform_device_put - destroy a platform device
 221 * @pdev: platform device to free
 222 *
 223 * Free all memory associated with a platform device.  This function must
 224 * _only_ be externally called in error cases.  All other usage is a bug.
 225 */
 226void platform_device_put(struct platform_device *pdev)
 227{
 228	if (pdev)
 229		put_device(&pdev->dev);
 230}
 231EXPORT_SYMBOL_GPL(platform_device_put);
 232
 233static void platform_device_release(struct device *dev)
 234{
 235	struct platform_object *pa = container_of(dev, struct platform_object,
 236						  pdev.dev);
 237
 238	of_device_node_put(&pa->pdev.dev);
 239	kfree(pa->pdev.dev.platform_data);
 240	kfree(pa->pdev.mfd_cell);
 241	kfree(pa->pdev.resource);
 242	kfree(pa->pdev.driver_override);
 243	kfree(pa);
 244}
 245
 246/**
 247 * platform_device_alloc - create a platform device
 248 * @name: base name of the device we're adding
 249 * @id: instance id
 250 *
 251 * Create a platform device object which can have other objects attached
 252 * to it, and which will have attached objects freed when it is released.
 253 */
 254struct platform_device *platform_device_alloc(const char *name, int id)
 255{
 256	struct platform_object *pa;
 257
 258	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 259	if (pa) {
 260		strcpy(pa->name, name);
 261		pa->pdev.name = pa->name;
 262		pa->pdev.id = id;
 263		device_initialize(&pa->pdev.dev);
 264		pa->pdev.dev.release = platform_device_release;
 265		arch_setup_pdev_archdata(&pa->pdev);
 266	}
 267
 268	return pa ? &pa->pdev : NULL;
 269}
 270EXPORT_SYMBOL_GPL(platform_device_alloc);
 271
 272/**
 273 * platform_device_add_resources - add resources to a platform device
 274 * @pdev: platform device allocated by platform_device_alloc to add resources to
 275 * @res: set of resources that needs to be allocated for the device
 276 * @num: number of resources
 277 *
 278 * Add a copy of the resources to the platform device.  The memory
 279 * associated with the resources will be freed when the platform device is
 280 * released.
 281 */
 282int platform_device_add_resources(struct platform_device *pdev,
 283				  const struct resource *res, unsigned int num)
 284{
 285	struct resource *r = NULL;
 286
 287	if (res) {
 288		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 289		if (!r)
 290			return -ENOMEM;
 291	}
 292
 293	kfree(pdev->resource);
 294	pdev->resource = r;
 295	pdev->num_resources = num;
 296	return 0;
 297}
 298EXPORT_SYMBOL_GPL(platform_device_add_resources);
 299
 300/**
 301 * platform_device_add_data - add platform-specific data to a platform device
 302 * @pdev: platform device allocated by platform_device_alloc to add resources to
 303 * @data: platform specific data for this platform device
 304 * @size: size of platform specific data
 305 *
 306 * Add a copy of platform specific data to the platform device's
 307 * platform_data pointer.  The memory associated with the platform data
 308 * will be freed when the platform device is released.
 309 */
 310int platform_device_add_data(struct platform_device *pdev, const void *data,
 311			     size_t size)
 312{
 313	void *d = NULL;
 314
 315	if (data) {
 316		d = kmemdup(data, size, GFP_KERNEL);
 317		if (!d)
 318			return -ENOMEM;
 319	}
 320
 321	kfree(pdev->dev.platform_data);
 322	pdev->dev.platform_data = d;
 323	return 0;
 324}
 325EXPORT_SYMBOL_GPL(platform_device_add_data);
 326
 327/**
 328 * platform_device_add_properties - add built-in properties to a platform device
 329 * @pdev: platform device to add properties to
 330 * @properties: null terminated array of properties to add
 331 *
 332 * The function will take deep copy of @properties and attach the copy to the
 333 * platform device. The memory associated with properties will be freed when the
 334 * platform device is released.
 335 */
 336int platform_device_add_properties(struct platform_device *pdev,
 337				   struct property_entry *properties)
 338{
 339	return device_add_properties(&pdev->dev, properties);
 340}
 341EXPORT_SYMBOL_GPL(platform_device_add_properties);
 342
 343/**
 344 * platform_device_add - add a platform device to device hierarchy
 345 * @pdev: platform device we're adding
 346 *
 347 * This is part 2 of platform_device_register(), though may be called
 348 * separately _iff_ pdev was allocated by platform_device_alloc().
 349 */
 350int platform_device_add(struct platform_device *pdev)
 351{
 352	int i, ret;
 
 353
 354	if (!pdev)
 355		return -EINVAL;
 356
 357	if (!pdev->dev.parent)
 358		pdev->dev.parent = &platform_bus;
 359
 360	pdev->dev.bus = &platform_bus_type;
 361
 362	switch (pdev->id) {
 363	default:
 364		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 365		break;
 366	case PLATFORM_DEVID_NONE:
 367		dev_set_name(&pdev->dev, "%s", pdev->name);
 368		break;
 369	case PLATFORM_DEVID_AUTO:
 370		/*
 371		 * Automatically allocated device ID. We mark it as such so
 372		 * that we remember it must be freed, and we append a suffix
 373		 * to avoid namespace collision with explicit IDs.
 374		 */
 375		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 376		if (ret < 0)
 377			goto err_out;
 378		pdev->id = ret;
 379		pdev->id_auto = true;
 380		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 381		break;
 382	}
 383
 384	for (i = 0; i < pdev->num_resources; i++) {
 385		struct resource *p, *r = &pdev->resource[i];
 386
 387		if (r->name == NULL)
 388			r->name = dev_name(&pdev->dev);
 389
 390		p = r->parent;
 391		if (!p) {
 392			if (resource_type(r) == IORESOURCE_MEM)
 393				p = &iomem_resource;
 394			else if (resource_type(r) == IORESOURCE_IO)
 395				p = &ioport_resource;
 396		}
 397
 398		if (p && insert_resource(p, r)) {
 399			dev_err(&pdev->dev, "failed to claim resource %d\n", i);
 400			ret = -EBUSY;
 401			goto failed;
 
 
 402		}
 403	}
 404
 405	pr_debug("Registering platform device '%s'. Parent at %s\n",
 406		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 407
 408	ret = device_add(&pdev->dev);
 409	if (ret == 0)
 410		return ret;
 411
 412 failed:
 413	if (pdev->id_auto) {
 414		ida_simple_remove(&platform_devid_ida, pdev->id);
 415		pdev->id = PLATFORM_DEVID_AUTO;
 416	}
 417
 418	while (--i >= 0) {
 419		struct resource *r = &pdev->resource[i];
 420		if (r->parent)
 421			release_resource(r);
 422	}
 423
 424 err_out:
 425	return ret;
 426}
 427EXPORT_SYMBOL_GPL(platform_device_add);
 428
 429/**
 430 * platform_device_del - remove a platform-level device
 431 * @pdev: platform device we're removing
 432 *
 433 * Note that this function will also release all memory- and port-based
 434 * resources owned by the device (@dev->resource).  This function must
 435 * _only_ be externally called in error cases.  All other usage is a bug.
 436 */
 437void platform_device_del(struct platform_device *pdev)
 438{
 439	int i;
 440
 441	if (pdev) {
 442		device_remove_properties(&pdev->dev);
 443		device_del(&pdev->dev);
 444
 445		if (pdev->id_auto) {
 446			ida_simple_remove(&platform_devid_ida, pdev->id);
 447			pdev->id = PLATFORM_DEVID_AUTO;
 448		}
 449
 450		for (i = 0; i < pdev->num_resources; i++) {
 451			struct resource *r = &pdev->resource[i];
 452			if (r->parent)
 453				release_resource(r);
 454		}
 455	}
 456}
 457EXPORT_SYMBOL_GPL(platform_device_del);
 458
 459/**
 460 * platform_device_register - add a platform-level device
 461 * @pdev: platform device we're adding
 462 */
 463int platform_device_register(struct platform_device *pdev)
 464{
 465	device_initialize(&pdev->dev);
 466	arch_setup_pdev_archdata(pdev);
 467	return platform_device_add(pdev);
 468}
 469EXPORT_SYMBOL_GPL(platform_device_register);
 470
 471/**
 472 * platform_device_unregister - unregister a platform-level device
 473 * @pdev: platform device we're unregistering
 474 *
 475 * Unregistration is done in 2 steps. First we release all resources
 476 * and remove it from the subsystem, then we drop reference count by
 477 * calling platform_device_put().
 478 */
 479void platform_device_unregister(struct platform_device *pdev)
 480{
 481	platform_device_del(pdev);
 482	platform_device_put(pdev);
 483}
 484EXPORT_SYMBOL_GPL(platform_device_unregister);
 485
 486/**
 487 * platform_device_register_full - add a platform-level device with
 488 * resources and platform-specific data
 489 *
 490 * @pdevinfo: data used to create device
 491 *
 492 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 493 */
 494struct platform_device *platform_device_register_full(
 495		const struct platform_device_info *pdevinfo)
 496{
 497	int ret = -ENOMEM;
 498	struct platform_device *pdev;
 499
 500	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 501	if (!pdev)
 502		goto err_alloc;
 503
 504	pdev->dev.parent = pdevinfo->parent;
 505	pdev->dev.fwnode = pdevinfo->fwnode;
 
 
 506
 507	if (pdevinfo->dma_mask) {
 508		/*
 509		 * This memory isn't freed when the device is put,
 510		 * I don't have a nice idea for that though.  Conceptually
 511		 * dma_mask in struct device should not be a pointer.
 512		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 513		 */
 514		pdev->dev.dma_mask =
 515			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 516		if (!pdev->dev.dma_mask)
 517			goto err;
 518
 519		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 520		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 521	}
 522
 523	ret = platform_device_add_resources(pdev,
 524			pdevinfo->res, pdevinfo->num_res);
 525	if (ret)
 526		goto err;
 527
 528	ret = platform_device_add_data(pdev,
 529			pdevinfo->data, pdevinfo->size_data);
 530	if (ret)
 531		goto err;
 532
 533	if (pdevinfo->properties) {
 534		ret = platform_device_add_properties(pdev,
 535						     pdevinfo->properties);
 536		if (ret)
 537			goto err;
 538	}
 539
 540	ret = platform_device_add(pdev);
 541	if (ret) {
 542err:
 543		ACPI_COMPANION_SET(&pdev->dev, NULL);
 544		kfree(pdev->dev.dma_mask);
 545
 546err_alloc:
 547		platform_device_put(pdev);
 548		return ERR_PTR(ret);
 549	}
 550
 551	return pdev;
 552}
 553EXPORT_SYMBOL_GPL(platform_device_register_full);
 554
 555static int platform_drv_probe(struct device *_dev)
 556{
 557	struct platform_driver *drv = to_platform_driver(_dev->driver);
 558	struct platform_device *dev = to_platform_device(_dev);
 559	int ret;
 560
 561	ret = of_clk_set_defaults(_dev->of_node, false);
 562	if (ret < 0)
 563		return ret;
 564
 565	ret = dev_pm_domain_attach(_dev, true);
 566	if (ret != -EPROBE_DEFER) {
 567		if (drv->probe) {
 568			ret = drv->probe(dev);
 569			if (ret)
 570				dev_pm_domain_detach(_dev, true);
 571		} else {
 572			/* don't fail if just dev_pm_domain_attach failed */
 573			ret = 0;
 574		}
 575	}
 576
 
 577	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 578		dev_warn(_dev, "probe deferral not supported\n");
 579		ret = -ENXIO;
 580	}
 581
 582	return ret;
 583}
 584
 585static int platform_drv_probe_fail(struct device *_dev)
 586{
 587	return -ENXIO;
 588}
 589
 590static int platform_drv_remove(struct device *_dev)
 591{
 592	struct platform_driver *drv = to_platform_driver(_dev->driver);
 593	struct platform_device *dev = to_platform_device(_dev);
 594	int ret = 0;
 595
 596	if (drv->remove)
 597		ret = drv->remove(dev);
 598	dev_pm_domain_detach(_dev, true);
 599
 600	return ret;
 601}
 602
 603static void platform_drv_shutdown(struct device *_dev)
 604{
 605	struct platform_driver *drv = to_platform_driver(_dev->driver);
 606	struct platform_device *dev = to_platform_device(_dev);
 607
 608	if (drv->shutdown)
 609		drv->shutdown(dev);
 610}
 611
 612/**
 613 * __platform_driver_register - register a driver for platform-level devices
 614 * @drv: platform driver structure
 615 * @owner: owning module/driver
 616 */
 617int __platform_driver_register(struct platform_driver *drv,
 618				struct module *owner)
 619{
 620	drv->driver.owner = owner;
 621	drv->driver.bus = &platform_bus_type;
 622	drv->driver.probe = platform_drv_probe;
 623	drv->driver.remove = platform_drv_remove;
 624	drv->driver.shutdown = platform_drv_shutdown;
 625
 626	return driver_register(&drv->driver);
 627}
 628EXPORT_SYMBOL_GPL(__platform_driver_register);
 629
 630/**
 631 * platform_driver_unregister - unregister a driver for platform-level devices
 632 * @drv: platform driver structure
 633 */
 634void platform_driver_unregister(struct platform_driver *drv)
 635{
 636	driver_unregister(&drv->driver);
 637}
 638EXPORT_SYMBOL_GPL(platform_driver_unregister);
 639
 640/**
 641 * __platform_driver_probe - register driver for non-hotpluggable device
 642 * @drv: platform driver structure
 643 * @probe: the driver probe routine, probably from an __init section
 644 * @module: module which will be the owner of the driver
 645 *
 646 * Use this instead of platform_driver_register() when you know the device
 647 * is not hotpluggable and has already been registered, and you want to
 648 * remove its run-once probe() infrastructure from memory after the driver
 649 * has bound to the device.
 650 *
 651 * One typical use for this would be with drivers for controllers integrated
 652 * into system-on-chip processors, where the controller devices have been
 653 * configured as part of board setup.
 654 *
 655 * Note that this is incompatible with deferred probing.
 656 *
 657 * Returns zero if the driver registered and bound to a device, else returns
 658 * a negative error code and with the driver not registered.
 659 */
 660int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 661		int (*probe)(struct platform_device *), struct module *module)
 662{
 663	int retval, code;
 664
 665	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 666		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 667			 drv->driver.name, __func__);
 668		return -EINVAL;
 669	}
 670
 671	/*
 672	 * We have to run our probes synchronously because we check if
 673	 * we find any devices to bind to and exit with error if there
 674	 * are any.
 675	 */
 676	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 677
 678	/*
 679	 * Prevent driver from requesting probe deferral to avoid further
 680	 * futile probe attempts.
 681	 */
 682	drv->prevent_deferred_probe = true;
 683
 684	/* make sure driver won't have bind/unbind attributes */
 685	drv->driver.suppress_bind_attrs = true;
 686
 687	/* temporary section violation during probe() */
 688	drv->probe = probe;
 689	retval = code = __platform_driver_register(drv, module);
 
 
 690
 691	/*
 692	 * Fixup that section violation, being paranoid about code scanning
 693	 * the list of drivers in order to probe new devices.  Check to see
 694	 * if the probe was successful, and make sure any forced probes of
 695	 * new devices fail.
 696	 */
 697	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 698	drv->probe = NULL;
 699	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 700		retval = -ENODEV;
 701	drv->driver.probe = platform_drv_probe_fail;
 702	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 703
 704	if (code != retval)
 705		platform_driver_unregister(drv);
 706	return retval;
 707}
 708EXPORT_SYMBOL_GPL(__platform_driver_probe);
 709
 710/**
 711 * __platform_create_bundle - register driver and create corresponding device
 712 * @driver: platform driver structure
 713 * @probe: the driver probe routine, probably from an __init section
 714 * @res: set of resources that needs to be allocated for the device
 715 * @n_res: number of resources
 716 * @data: platform specific data for this platform device
 717 * @size: size of platform specific data
 718 * @module: module which will be the owner of the driver
 719 *
 720 * Use this in legacy-style modules that probe hardware directly and
 721 * register a single platform device and corresponding platform driver.
 722 *
 723 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 724 */
 725struct platform_device * __init_or_module __platform_create_bundle(
 726			struct platform_driver *driver,
 727			int (*probe)(struct platform_device *),
 728			struct resource *res, unsigned int n_res,
 729			const void *data, size_t size, struct module *module)
 730{
 731	struct platform_device *pdev;
 732	int error;
 733
 734	pdev = platform_device_alloc(driver->driver.name, -1);
 735	if (!pdev) {
 736		error = -ENOMEM;
 737		goto err_out;
 738	}
 739
 740	error = platform_device_add_resources(pdev, res, n_res);
 741	if (error)
 742		goto err_pdev_put;
 743
 744	error = platform_device_add_data(pdev, data, size);
 745	if (error)
 746		goto err_pdev_put;
 747
 748	error = platform_device_add(pdev);
 749	if (error)
 750		goto err_pdev_put;
 751
 752	error = __platform_driver_probe(driver, probe, module);
 753	if (error)
 754		goto err_pdev_del;
 755
 756	return pdev;
 757
 758err_pdev_del:
 759	platform_device_del(pdev);
 760err_pdev_put:
 761	platform_device_put(pdev);
 762err_out:
 763	return ERR_PTR(error);
 764}
 765EXPORT_SYMBOL_GPL(__platform_create_bundle);
 766
 767/**
 768 * __platform_register_drivers - register an array of platform drivers
 769 * @drivers: an array of drivers to register
 770 * @count: the number of drivers to register
 771 * @owner: module owning the drivers
 772 *
 773 * Registers platform drivers specified by an array. On failure to register a
 774 * driver, all previously registered drivers will be unregistered. Callers of
 775 * this API should use platform_unregister_drivers() to unregister drivers in
 776 * the reverse order.
 777 *
 778 * Returns: 0 on success or a negative error code on failure.
 779 */
 780int __platform_register_drivers(struct platform_driver * const *drivers,
 781				unsigned int count, struct module *owner)
 782{
 783	unsigned int i;
 784	int err;
 785
 786	for (i = 0; i < count; i++) {
 787		pr_debug("registering platform driver %ps\n", drivers[i]);
 788
 789		err = __platform_driver_register(drivers[i], owner);
 790		if (err < 0) {
 791			pr_err("failed to register platform driver %ps: %d\n",
 792			       drivers[i], err);
 793			goto error;
 794		}
 795	}
 796
 797	return 0;
 798
 799error:
 800	while (i--) {
 801		pr_debug("unregistering platform driver %ps\n", drivers[i]);
 802		platform_driver_unregister(drivers[i]);
 803	}
 804
 805	return err;
 806}
 807EXPORT_SYMBOL_GPL(__platform_register_drivers);
 808
 809/**
 810 * platform_unregister_drivers - unregister an array of platform drivers
 811 * @drivers: an array of drivers to unregister
 812 * @count: the number of drivers to unregister
 813 *
 814 * Unegisters platform drivers specified by an array. This is typically used
 815 * to complement an earlier call to platform_register_drivers(). Drivers are
 816 * unregistered in the reverse order in which they were registered.
 817 */
 818void platform_unregister_drivers(struct platform_driver * const *drivers,
 819				 unsigned int count)
 820{
 821	while (count--) {
 822		pr_debug("unregistering platform driver %ps\n", drivers[count]);
 823		platform_driver_unregister(drivers[count]);
 824	}
 825}
 826EXPORT_SYMBOL_GPL(platform_unregister_drivers);
 827
 828/* modalias support enables more hands-off userspace setup:
 829 * (a) environment variable lets new-style hotplug events work once system is
 830 *     fully running:  "modprobe $MODALIAS"
 831 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 832 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 833 */
 834static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 835			     char *buf)
 836{
 837	struct platform_device	*pdev = to_platform_device(dev);
 838	int len;
 839
 840	len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
 841	if (len != -ENODEV)
 842		return len;
 843
 844	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 845	if (len != -ENODEV)
 846		return len;
 847
 848	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 849
 850	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 851}
 852static DEVICE_ATTR_RO(modalias);
 853
 854static ssize_t driver_override_store(struct device *dev,
 855				     struct device_attribute *attr,
 856				     const char *buf, size_t count)
 857{
 858	struct platform_device *pdev = to_platform_device(dev);
 859	char *driver_override, *old = pdev->driver_override, *cp;
 860
 861	if (count > PATH_MAX)
 
 862		return -EINVAL;
 863
 864	driver_override = kstrndup(buf, count, GFP_KERNEL);
 865	if (!driver_override)
 866		return -ENOMEM;
 867
 868	cp = strchr(driver_override, '\n');
 869	if (cp)
 870		*cp = '\0';
 871
 
 
 872	if (strlen(driver_override)) {
 873		pdev->driver_override = driver_override;
 874	} else {
 875		kfree(driver_override);
 876		pdev->driver_override = NULL;
 877	}
 
 878
 879	kfree(old);
 880
 881	return count;
 882}
 883
 884static ssize_t driver_override_show(struct device *dev,
 885				    struct device_attribute *attr, char *buf)
 886{
 887	struct platform_device *pdev = to_platform_device(dev);
 
 888
 889	return sprintf(buf, "%s\n", pdev->driver_override);
 
 
 
 890}
 891static DEVICE_ATTR_RW(driver_override);
 892
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 893
 894static struct attribute *platform_dev_attrs[] = {
 895	&dev_attr_modalias.attr,
 
 896	&dev_attr_driver_override.attr,
 897	NULL,
 898};
 899ATTRIBUTE_GROUPS(platform_dev);
 
 
 
 
 
 900
 901static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 902{
 903	struct platform_device	*pdev = to_platform_device(dev);
 904	int rc;
 905
 906	/* Some devices have extra OF data and an OF-style MODALIAS */
 907	rc = of_device_uevent_modalias(dev, env);
 908	if (rc != -ENODEV)
 909		return rc;
 910
 911	rc = acpi_device_uevent_modalias(dev, env);
 912	if (rc != -ENODEV)
 913		return rc;
 914
 915	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 916			pdev->name);
 917	return 0;
 918}
 919
 920static const struct platform_device_id *platform_match_id(
 921			const struct platform_device_id *id,
 922			struct platform_device *pdev)
 923{
 924	while (id->name[0]) {
 925		if (strcmp(pdev->name, id->name) == 0) {
 926			pdev->id_entry = id;
 927			return id;
 928		}
 929		id++;
 930	}
 931	return NULL;
 932}
 933
 934/**
 935 * platform_match - bind platform device to platform driver.
 936 * @dev: device.
 937 * @drv: driver.
 938 *
 939 * Platform device IDs are assumed to be encoded like this:
 940 * "<name><instance>", where <name> is a short description of the type of
 941 * device, like "pci" or "floppy", and <instance> is the enumerated
 942 * instance of the device, like '0' or '42'.  Driver IDs are simply
 943 * "<name>".  So, extract the <name> from the platform_device structure,
 944 * and compare it against the name of the driver. Return whether they match
 945 * or not.
 946 */
 947static int platform_match(struct device *dev, struct device_driver *drv)
 948{
 949	struct platform_device *pdev = to_platform_device(dev);
 950	struct platform_driver *pdrv = to_platform_driver(drv);
 951
 952	/* When driver_override is set, only bind to the matching driver */
 953	if (pdev->driver_override)
 954		return !strcmp(pdev->driver_override, drv->name);
 955
 956	/* Attempt an OF style match first */
 957	if (of_driver_match_device(dev, drv))
 958		return 1;
 959
 960	/* Then try ACPI style match */
 961	if (acpi_driver_match_device(dev, drv))
 962		return 1;
 963
 964	/* Then try to match against the id table */
 965	if (pdrv->id_table)
 966		return platform_match_id(pdrv->id_table, pdev) != NULL;
 967
 968	/* fall-back to driver name match */
 969	return (strcmp(pdev->name, drv->name) == 0);
 970}
 971
 972#ifdef CONFIG_PM_SLEEP
 973
 974static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 975{
 976	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 977	struct platform_device *pdev = to_platform_device(dev);
 978	int ret = 0;
 979
 980	if (dev->driver && pdrv->suspend)
 981		ret = pdrv->suspend(pdev, mesg);
 982
 983	return ret;
 984}
 985
 986static int platform_legacy_resume(struct device *dev)
 987{
 988	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 989	struct platform_device *pdev = to_platform_device(dev);
 990	int ret = 0;
 991
 992	if (dev->driver && pdrv->resume)
 993		ret = pdrv->resume(pdev);
 994
 995	return ret;
 996}
 997
 998#endif /* CONFIG_PM_SLEEP */
 999
1000#ifdef CONFIG_SUSPEND
1001
1002int platform_pm_suspend(struct device *dev)
1003{
1004	struct device_driver *drv = dev->driver;
1005	int ret = 0;
1006
1007	if (!drv)
1008		return 0;
1009
1010	if (drv->pm) {
1011		if (drv->pm->suspend)
1012			ret = drv->pm->suspend(dev);
1013	} else {
1014		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1015	}
1016
1017	return ret;
1018}
1019
1020int platform_pm_resume(struct device *dev)
1021{
1022	struct device_driver *drv = dev->driver;
1023	int ret = 0;
1024
1025	if (!drv)
1026		return 0;
1027
1028	if (drv->pm) {
1029		if (drv->pm->resume)
1030			ret = drv->pm->resume(dev);
1031	} else {
1032		ret = platform_legacy_resume(dev);
1033	}
1034
1035	return ret;
1036}
1037
1038#endif /* CONFIG_SUSPEND */
1039
1040#ifdef CONFIG_HIBERNATE_CALLBACKS
1041
1042int platform_pm_freeze(struct device *dev)
1043{
1044	struct device_driver *drv = dev->driver;
1045	int ret = 0;
1046
1047	if (!drv)
1048		return 0;
1049
1050	if (drv->pm) {
1051		if (drv->pm->freeze)
1052			ret = drv->pm->freeze(dev);
1053	} else {
1054		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1055	}
1056
1057	return ret;
1058}
1059
1060int platform_pm_thaw(struct device *dev)
1061{
1062	struct device_driver *drv = dev->driver;
1063	int ret = 0;
1064
1065	if (!drv)
1066		return 0;
1067
1068	if (drv->pm) {
1069		if (drv->pm->thaw)
1070			ret = drv->pm->thaw(dev);
1071	} else {
1072		ret = platform_legacy_resume(dev);
1073	}
1074
1075	return ret;
1076}
1077
1078int platform_pm_poweroff(struct device *dev)
1079{
1080	struct device_driver *drv = dev->driver;
1081	int ret = 0;
1082
1083	if (!drv)
1084		return 0;
1085
1086	if (drv->pm) {
1087		if (drv->pm->poweroff)
1088			ret = drv->pm->poweroff(dev);
1089	} else {
1090		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1091	}
1092
1093	return ret;
1094}
1095
1096int platform_pm_restore(struct device *dev)
1097{
1098	struct device_driver *drv = dev->driver;
1099	int ret = 0;
1100
1101	if (!drv)
1102		return 0;
1103
1104	if (drv->pm) {
1105		if (drv->pm->restore)
1106			ret = drv->pm->restore(dev);
1107	} else {
1108		ret = platform_legacy_resume(dev);
1109	}
1110
1111	return ret;
1112}
1113
1114#endif /* CONFIG_HIBERNATE_CALLBACKS */
1115
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1116static const struct dev_pm_ops platform_dev_pm_ops = {
1117	.runtime_suspend = pm_generic_runtime_suspend,
1118	.runtime_resume = pm_generic_runtime_resume,
1119	USE_PLATFORM_PM_SLEEP_OPS
1120};
1121
1122struct bus_type platform_bus_type = {
1123	.name		= "platform",
1124	.dev_groups	= platform_dev_groups,
1125	.match		= platform_match,
1126	.uevent		= platform_uevent,
 
1127	.pm		= &platform_dev_pm_ops,
1128};
1129EXPORT_SYMBOL_GPL(platform_bus_type);
1130
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1131int __init platform_bus_init(void)
1132{
1133	int error;
1134
1135	early_platform_cleanup();
1136
1137	error = device_register(&platform_bus);
1138	if (error)
 
1139		return error;
 
1140	error =  bus_register(&platform_bus_type);
1141	if (error)
1142		device_unregister(&platform_bus);
1143	of_platform_register_reconfig_notifier();
1144	return error;
1145}
1146
1147#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1148u64 dma_get_required_mask(struct device *dev)
1149{
1150	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1151	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1152	u64 mask;
1153
1154	if (!high_totalram) {
1155		/* convert to mask just covering totalram */
1156		low_totalram = (1 << (fls(low_totalram) - 1));
1157		low_totalram += low_totalram - 1;
1158		mask = low_totalram;
1159	} else {
1160		high_totalram = (1 << (fls(high_totalram) - 1));
1161		high_totalram += high_totalram - 1;
1162		mask = (((u64)high_totalram) << 32) + 0xffffffff;
1163	}
1164	return mask;
1165}
1166EXPORT_SYMBOL_GPL(dma_get_required_mask);
1167#endif
1168
1169static __initdata LIST_HEAD(early_platform_driver_list);
1170static __initdata LIST_HEAD(early_platform_device_list);
1171
1172/**
1173 * early_platform_driver_register - register early platform driver
1174 * @epdrv: early_platform driver structure
1175 * @buf: string passed from early_param()
1176 *
1177 * Helper function for early_platform_init() / early_platform_init_buffer()
1178 */
1179int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1180					  char *buf)
1181{
1182	char *tmp;
1183	int n;
1184
1185	/* Simply add the driver to the end of the global list.
1186	 * Drivers will by default be put on the list in compiled-in order.
1187	 */
1188	if (!epdrv->list.next) {
1189		INIT_LIST_HEAD(&epdrv->list);
1190		list_add_tail(&epdrv->list, &early_platform_driver_list);
1191	}
1192
1193	/* If the user has specified device then make sure the driver
1194	 * gets prioritized. The driver of the last device specified on
1195	 * command line will be put first on the list.
1196	 */
1197	n = strlen(epdrv->pdrv->driver.name);
1198	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1199		list_move(&epdrv->list, &early_platform_driver_list);
1200
1201		/* Allow passing parameters after device name */
1202		if (buf[n] == '\0' || buf[n] == ',')
1203			epdrv->requested_id = -1;
1204		else {
1205			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1206							     &tmp, 10);
1207
1208			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1209				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1210				n = 0;
1211			} else
1212				n += strcspn(&buf[n + 1], ",") + 1;
1213		}
1214
1215		if (buf[n] == ',')
1216			n++;
1217
1218		if (epdrv->bufsize) {
1219			memcpy(epdrv->buffer, &buf[n],
1220			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1221			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1222		}
1223	}
1224
1225	return 0;
1226}
1227
1228/**
1229 * early_platform_add_devices - adds a number of early platform devices
1230 * @devs: array of early platform devices to add
1231 * @num: number of early platform devices in array
1232 *
1233 * Used by early architecture code to register early platform devices and
1234 * their platform data.
1235 */
1236void __init early_platform_add_devices(struct platform_device **devs, int num)
1237{
1238	struct device *dev;
1239	int i;
1240
1241	/* simply add the devices to list */
1242	for (i = 0; i < num; i++) {
1243		dev = &devs[i]->dev;
1244
1245		if (!dev->devres_head.next) {
1246			pm_runtime_early_init(dev);
1247			INIT_LIST_HEAD(&dev->devres_head);
1248			list_add_tail(&dev->devres_head,
1249				      &early_platform_device_list);
1250		}
1251	}
1252}
1253
1254/**
1255 * early_platform_driver_register_all - register early platform drivers
1256 * @class_str: string to identify early platform driver class
1257 *
1258 * Used by architecture code to register all early platform drivers
1259 * for a certain class. If omitted then only early platform drivers
1260 * with matching kernel command line class parameters will be registered.
1261 */
1262void __init early_platform_driver_register_all(char *class_str)
1263{
1264	/* The "class_str" parameter may or may not be present on the kernel
1265	 * command line. If it is present then there may be more than one
1266	 * matching parameter.
1267	 *
1268	 * Since we register our early platform drivers using early_param()
1269	 * we need to make sure that they also get registered in the case
1270	 * when the parameter is missing from the kernel command line.
1271	 *
1272	 * We use parse_early_options() to make sure the early_param() gets
1273	 * called at least once. The early_param() may be called more than
1274	 * once since the name of the preferred device may be specified on
1275	 * the kernel command line. early_platform_driver_register() handles
1276	 * this case for us.
1277	 */
1278	parse_early_options(class_str);
1279}
1280
1281/**
1282 * early_platform_match - find early platform device matching driver
1283 * @epdrv: early platform driver structure
1284 * @id: id to match against
1285 */
1286static struct platform_device * __init
1287early_platform_match(struct early_platform_driver *epdrv, int id)
1288{
1289	struct platform_device *pd;
1290
1291	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1292		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1293			if (pd->id == id)
1294				return pd;
1295
1296	return NULL;
1297}
1298
1299/**
1300 * early_platform_left - check if early platform driver has matching devices
1301 * @epdrv: early platform driver structure
1302 * @id: return true if id or above exists
1303 */
1304static int __init early_platform_left(struct early_platform_driver *epdrv,
1305				       int id)
1306{
1307	struct platform_device *pd;
1308
1309	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1310		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1311			if (pd->id >= id)
1312				return 1;
1313
1314	return 0;
1315}
1316
1317/**
1318 * early_platform_driver_probe_id - probe drivers matching class_str and id
1319 * @class_str: string to identify early platform driver class
1320 * @id: id to match against
1321 * @nr_probe: number of platform devices to successfully probe before exiting
1322 */
1323static int __init early_platform_driver_probe_id(char *class_str,
1324						 int id,
1325						 int nr_probe)
1326{
1327	struct early_platform_driver *epdrv;
1328	struct platform_device *match;
1329	int match_id;
1330	int n = 0;
1331	int left = 0;
1332
1333	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1334		/* only use drivers matching our class_str */
1335		if (strcmp(class_str, epdrv->class_str))
1336			continue;
1337
1338		if (id == -2) {
1339			match_id = epdrv->requested_id;
1340			left = 1;
1341
1342		} else {
1343			match_id = id;
1344			left += early_platform_left(epdrv, id);
1345
1346			/* skip requested id */
1347			switch (epdrv->requested_id) {
1348			case EARLY_PLATFORM_ID_ERROR:
1349			case EARLY_PLATFORM_ID_UNSET:
1350				break;
1351			default:
1352				if (epdrv->requested_id == id)
1353					match_id = EARLY_PLATFORM_ID_UNSET;
1354			}
1355		}
1356
1357		switch (match_id) {
1358		case EARLY_PLATFORM_ID_ERROR:
1359			pr_warn("%s: unable to parse %s parameter\n",
1360				class_str, epdrv->pdrv->driver.name);
1361			/* fall-through */
1362		case EARLY_PLATFORM_ID_UNSET:
1363			match = NULL;
1364			break;
1365		default:
1366			match = early_platform_match(epdrv, match_id);
1367		}
1368
1369		if (match) {
1370			/*
1371			 * Set up a sensible init_name to enable
1372			 * dev_name() and others to be used before the
1373			 * rest of the driver core is initialized.
1374			 */
1375			if (!match->dev.init_name && slab_is_available()) {
1376				if (match->id != -1)
1377					match->dev.init_name =
1378						kasprintf(GFP_KERNEL, "%s.%d",
1379							  match->name,
1380							  match->id);
1381				else
1382					match->dev.init_name =
1383						kasprintf(GFP_KERNEL, "%s",
1384							  match->name);
1385
1386				if (!match->dev.init_name)
1387					return -ENOMEM;
1388			}
1389
1390			if (epdrv->pdrv->probe(match))
1391				pr_warn("%s: unable to probe %s early.\n",
1392					class_str, match->name);
1393			else
1394				n++;
1395		}
1396
1397		if (n >= nr_probe)
1398			break;
1399	}
1400
1401	if (left)
1402		return n;
1403	else
1404		return -ENODEV;
1405}
1406
1407/**
1408 * early_platform_driver_probe - probe a class of registered drivers
1409 * @class_str: string to identify early platform driver class
1410 * @nr_probe: number of platform devices to successfully probe before exiting
1411 * @user_only: only probe user specified early platform devices
1412 *
1413 * Used by architecture code to probe registered early platform drivers
1414 * within a certain class. For probe to happen a registered early platform
1415 * device matching a registered early platform driver is needed.
1416 */
1417int __init early_platform_driver_probe(char *class_str,
1418				       int nr_probe,
1419				       int user_only)
1420{
1421	int k, n, i;
1422
1423	n = 0;
1424	for (i = -2; n < nr_probe; i++) {
1425		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1426
1427		if (k < 0)
1428			break;
1429
1430		n += k;
1431
1432		if (user_only)
1433			break;
1434	}
1435
1436	return n;
1437}
1438
1439/**
1440 * early_platform_cleanup - clean up early platform code
1441 */
1442void __init early_platform_cleanup(void)
1443{
1444	struct platform_device *pd, *pd2;
1445
1446	/* clean up the devres list used to chain devices */
1447	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1448				 dev.devres_head) {
1449		list_del(&pd->dev.devres_head);
1450		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1451	}
1452}
1453