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v6.2
   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#include <linux/iommu.h>
  34#include <linux/dma-map-ops.h>
  35
  36#include "base.h"
  37#include "power/power.h"
  38
  39/* For automatically allocated device IDs */
  40static DEFINE_IDA(platform_devid_ida);
  41
  42struct device platform_bus = {
  43	.init_name	= "platform",
  44};
  45EXPORT_SYMBOL_GPL(platform_bus);
  46
  47/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  48 * platform_get_resource - get a resource for a device
  49 * @dev: platform device
  50 * @type: resource type
  51 * @num: resource index
  52 *
  53 * Return: a pointer to the resource or NULL on failure.
  54 */
  55struct resource *platform_get_resource(struct platform_device *dev,
  56				       unsigned int type, unsigned int num)
  57{
  58	u32 i;
  59
  60	for (i = 0; i < dev->num_resources; i++) {
  61		struct resource *r = &dev->resource[i];
  62
  63		if (type == resource_type(r) && num-- == 0)
  64			return r;
  65	}
  66	return NULL;
  67}
  68EXPORT_SYMBOL_GPL(platform_get_resource);
  69
  70struct resource *platform_get_mem_or_io(struct platform_device *dev,
  71					unsigned int num)
  72{
  73	u32 i;
  74
  75	for (i = 0; i < dev->num_resources; i++) {
  76		struct resource *r = &dev->resource[i];
  77
  78		if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
  79			return r;
  80	}
  81	return NULL;
  82}
  83EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
  84
  85#ifdef CONFIG_HAS_IOMEM
  86/**
  87 * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
  88 *					    platform device and get resource
  89 *
  90 * @pdev: platform device to use both for memory resource lookup as well as
  91 *        resource management
  92 * @index: resource index
  93 * @res: optional output parameter to store a pointer to the obtained resource.
  94 *
  95 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
  96 * on failure.
  97 */
  98void __iomem *
  99devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
 100				unsigned int index, struct resource **res)
 101{
 102	struct resource *r;
 103
 104	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
 105	if (res)
 106		*res = r;
 107	return devm_ioremap_resource(&pdev->dev, r);
 108}
 109EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
 110
 111/**
 112 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
 113 *				    device
 114 *
 115 * @pdev: platform device to use both for memory resource lookup as well as
 116 *        resource management
 117 * @index: resource index
 118 *
 119 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 120 * on failure.
 121 */
 122void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
 123					     unsigned int index)
 124{
 125	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
 126}
 127EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
 128
 129/**
 130 * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
 131 *					   a platform device, retrieve the
 132 *					   resource by name
 133 *
 134 * @pdev: platform device to use both for memory resource lookup as well as
 135 *	  resource management
 136 * @name: name of the resource
 137 *
 138 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
 139 * on failure.
 140 */
 141void __iomem *
 142devm_platform_ioremap_resource_byname(struct platform_device *pdev,
 143				      const char *name)
 144{
 145	struct resource *res;
 146
 147	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 148	return devm_ioremap_resource(&pdev->dev, res);
 149}
 150EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
 151#endif /* CONFIG_HAS_IOMEM */
 152
 153/**
 154 * platform_get_irq_optional - get an optional IRQ for a device
 155 * @dev: platform device
 156 * @num: IRQ number index
 157 *
 158 * Gets an IRQ for a platform device. Device drivers should check the return
 159 * value for errors so as to not pass a negative integer value to the
 160 * request_irq() APIs. This is the same as platform_get_irq(), except that it
 161 * does not print an error message if an IRQ can not be obtained.
 162 *
 163 * For example::
 164 *
 165 *		int irq = platform_get_irq_optional(pdev, 0);
 166 *		if (irq < 0)
 167 *			return irq;
 168 *
 169 * Return: non-zero IRQ number on success, negative error number on failure.
 170 */
 171int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 172{
 173	int ret;
 174#ifdef CONFIG_SPARC
 175	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
 176	if (!dev || num >= dev->archdata.num_irqs)
 177		goto out_not_found;
 178	ret = dev->archdata.irqs[num];
 179	goto out;
 180#else
 181	struct resource *r;
 182
 183	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 
 
 184		ret = of_irq_get(dev->dev.of_node, num);
 185		if (ret > 0 || ret == -EPROBE_DEFER)
 186			goto out;
 187	}
 188
 189	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 190	if (has_acpi_companion(&dev->dev)) {
 191		if (r && r->flags & IORESOURCE_DISABLED) {
 
 
 192			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 193			if (ret)
 194				goto out;
 195		}
 196	}
 197
 198	/*
 199	 * The resources may pass trigger flags to the irqs that need
 200	 * to be set up. It so happens that the trigger flags for
 201	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 202	 * settings.
 203	 */
 204	if (r && r->flags & IORESOURCE_BITS) {
 205		struct irq_data *irqd;
 206
 207		irqd = irq_get_irq_data(r->start);
 208		if (!irqd)
 209			goto out_not_found;
 210		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 211	}
 212
 213	if (r) {
 214		ret = r->start;
 215		goto out;
 216	}
 217
 218	/*
 219	 * For the index 0 interrupt, allow falling back to GpioInt
 220	 * resources. While a device could have both Interrupt and GpioInt
 221	 * resources, making this fallback ambiguous, in many common cases
 222	 * the device will only expose one IRQ, and this fallback
 223	 * allows a common code path across either kind of resource.
 224	 */
 225	if (num == 0 && has_acpi_companion(&dev->dev)) {
 226		ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
 227		/* Our callers expect -ENXIO for missing IRQs. */
 228		if (ret >= 0 || ret == -EPROBE_DEFER)
 229			goto out;
 230	}
 231
 232#endif
 233out_not_found:
 234	ret = -ENXIO;
 235out:
 236	if (WARN(!ret, "0 is an invalid IRQ number\n"))
 237		return -EINVAL;
 238	return ret;
 239}
 240EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 241
 242/**
 243 * platform_get_irq - get an IRQ for a device
 244 * @dev: platform device
 245 * @num: IRQ number index
 246 *
 247 * Gets an IRQ for a platform device and prints an error message if finding the
 248 * IRQ fails. Device drivers should check the return value for errors so as to
 249 * not pass a negative integer value to the request_irq() APIs.
 250 *
 251 * For example::
 252 *
 253 *		int irq = platform_get_irq(pdev, 0);
 254 *		if (irq < 0)
 255 *			return irq;
 256 *
 257 * Return: non-zero IRQ number on success, negative error number on failure.
 258 */
 259int platform_get_irq(struct platform_device *dev, unsigned int num)
 260{
 261	int ret;
 262
 263	ret = platform_get_irq_optional(dev, num);
 264	if (ret < 0)
 265		return dev_err_probe(&dev->dev, ret,
 266				     "IRQ index %u not found\n", num);
 267
 268	return ret;
 269}
 270EXPORT_SYMBOL_GPL(platform_get_irq);
 271
 272/**
 273 * platform_irq_count - Count the number of IRQs a platform device uses
 274 * @dev: platform device
 275 *
 276 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 277 */
 278int platform_irq_count(struct platform_device *dev)
 279{
 280	int ret, nr = 0;
 281
 282	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
 283		nr++;
 284
 285	if (ret == -EPROBE_DEFER)
 286		return ret;
 287
 288	return nr;
 289}
 290EXPORT_SYMBOL_GPL(platform_irq_count);
 291
 292struct irq_affinity_devres {
 293	unsigned int count;
 294	unsigned int irq[];
 295};
 296
 297static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
 298{
 299	struct resource *r;
 300
 301	r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
 302	if (r)
 303		irqresource_disabled(r, 0);
 304}
 305
 306static void devm_platform_get_irqs_affinity_release(struct device *dev,
 307						    void *res)
 308{
 309	struct irq_affinity_devres *ptr = res;
 310	int i;
 311
 312	for (i = 0; i < ptr->count; i++) {
 313		irq_dispose_mapping(ptr->irq[i]);
 314
 315		if (has_acpi_companion(dev))
 316			platform_disable_acpi_irq(to_platform_device(dev), i);
 317	}
 318}
 319
 320/**
 321 * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
 322 *				device using an interrupt affinity descriptor
 323 * @dev: platform device pointer
 324 * @affd: affinity descriptor
 325 * @minvec: minimum count of interrupt vectors
 326 * @maxvec: maximum count of interrupt vectors
 327 * @irqs: pointer holder for IRQ numbers
 328 *
 329 * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
 330 * to the passed affinity descriptor
 331 *
 332 * Return: Number of vectors on success, negative error number on failure.
 333 */
 334int devm_platform_get_irqs_affinity(struct platform_device *dev,
 335				    struct irq_affinity *affd,
 336				    unsigned int minvec,
 337				    unsigned int maxvec,
 338				    int **irqs)
 339{
 340	struct irq_affinity_devres *ptr;
 341	struct irq_affinity_desc *desc;
 342	size_t size;
 343	int i, ret, nvec;
 344
 345	if (!affd)
 346		return -EPERM;
 347
 348	if (maxvec < minvec)
 349		return -ERANGE;
 350
 351	nvec = platform_irq_count(dev);
 352	if (nvec < 0)
 353		return nvec;
 354
 355	if (nvec < minvec)
 356		return -ENOSPC;
 357
 358	nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
 359	if (nvec < minvec)
 360		return -ENOSPC;
 361
 362	if (nvec > maxvec)
 363		nvec = maxvec;
 364
 365	size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
 366	ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
 367			   GFP_KERNEL);
 368	if (!ptr)
 369		return -ENOMEM;
 370
 371	ptr->count = nvec;
 372
 373	for (i = 0; i < nvec; i++) {
 374		int irq = platform_get_irq(dev, i);
 375		if (irq < 0) {
 376			ret = irq;
 377			goto err_free_devres;
 378		}
 379		ptr->irq[i] = irq;
 380	}
 381
 382	desc = irq_create_affinity_masks(nvec, affd);
 383	if (!desc) {
 384		ret = -ENOMEM;
 385		goto err_free_devres;
 386	}
 387
 388	for (i = 0; i < nvec; i++) {
 389		ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
 390		if (ret) {
 391			dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
 392				ptr->irq[i], ret);
 393			goto err_free_desc;
 394		}
 395	}
 396
 397	devres_add(&dev->dev, ptr);
 398
 399	kfree(desc);
 400
 401	*irqs = ptr->irq;
 402
 403	return nvec;
 404
 405err_free_desc:
 406	kfree(desc);
 407err_free_devres:
 408	devres_free(ptr);
 409	return ret;
 410}
 411EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
 412
 413/**
 414 * platform_get_resource_byname - get a resource for a device by name
 415 * @dev: platform device
 416 * @type: resource type
 417 * @name: resource name
 418 */
 419struct resource *platform_get_resource_byname(struct platform_device *dev,
 420					      unsigned int type,
 421					      const char *name)
 422{
 423	u32 i;
 424
 425	for (i = 0; i < dev->num_resources; i++) {
 426		struct resource *r = &dev->resource[i];
 427
 428		if (unlikely(!r->name))
 429			continue;
 430
 431		if (type == resource_type(r) && !strcmp(r->name, name))
 432			return r;
 433	}
 434	return NULL;
 435}
 436EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 437
 438static int __platform_get_irq_byname(struct platform_device *dev,
 439				     const char *name)
 440{
 441	struct resource *r;
 442	int ret;
 443
 444	if (!dev->dev.of_node || IS_ENABLED(CONFIG_OF_IRQ)) {
 445		ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
 446		if (ret > 0 || ret == -EPROBE_DEFER)
 447			return ret;
 448	}
 449
 450	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 451	if (r) {
 452		if (WARN(!r->start, "0 is an invalid IRQ number\n"))
 453			return -EINVAL;
 454		return r->start;
 455	}
 456
 457	return -ENXIO;
 458}
 459
 460/**
 461 * platform_get_irq_byname - get an IRQ for a device by name
 462 * @dev: platform device
 463 * @name: IRQ name
 464 *
 465 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
 466 *
 467 * Return: non-zero IRQ number on success, negative error number on failure.
 468 */
 469int platform_get_irq_byname(struct platform_device *dev, const char *name)
 470{
 471	int ret;
 472
 473	ret = __platform_get_irq_byname(dev, name);
 474	if (ret < 0)
 475		return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
 476				     name);
 477	return ret;
 478}
 479EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 480
 481/**
 482 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
 483 * @dev: platform device
 484 * @name: IRQ name
 485 *
 486 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
 487 * does not print an error message if an IRQ can not be obtained.
 488 *
 489 * Return: non-zero IRQ number on success, negative error number on failure.
 490 */
 491int platform_get_irq_byname_optional(struct platform_device *dev,
 492				     const char *name)
 493{
 494	return __platform_get_irq_byname(dev, name);
 495}
 496EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
 497
 498/**
 499 * platform_add_devices - add a numbers of platform devices
 500 * @devs: array of platform devices to add
 501 * @num: number of platform devices in array
 502 */
 503int platform_add_devices(struct platform_device **devs, int num)
 504{
 505	int i, ret = 0;
 506
 507	for (i = 0; i < num; i++) {
 508		ret = platform_device_register(devs[i]);
 509		if (ret) {
 510			while (--i >= 0)
 511				platform_device_unregister(devs[i]);
 512			break;
 513		}
 514	}
 515
 516	return ret;
 517}
 518EXPORT_SYMBOL_GPL(platform_add_devices);
 519
 520struct platform_object {
 521	struct platform_device pdev;
 522	char name[];
 523};
 524
 525/*
 526 * Set up default DMA mask for platform devices if the they weren't
 527 * previously set by the architecture / DT.
 528 */
 529static void setup_pdev_dma_masks(struct platform_device *pdev)
 530{
 531	pdev->dev.dma_parms = &pdev->dma_parms;
 532
 533	if (!pdev->dev.coherent_dma_mask)
 534		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 535	if (!pdev->dev.dma_mask) {
 536		pdev->platform_dma_mask = DMA_BIT_MASK(32);
 537		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 538	}
 539};
 540
 541/**
 542 * platform_device_put - destroy a platform device
 543 * @pdev: platform device to free
 544 *
 545 * Free all memory associated with a platform device.  This function must
 546 * _only_ be externally called in error cases.  All other usage is a bug.
 547 */
 548void platform_device_put(struct platform_device *pdev)
 549{
 550	if (!IS_ERR_OR_NULL(pdev))
 551		put_device(&pdev->dev);
 552}
 553EXPORT_SYMBOL_GPL(platform_device_put);
 554
 555static void platform_device_release(struct device *dev)
 556{
 557	struct platform_object *pa = container_of(dev, struct platform_object,
 558						  pdev.dev);
 559
 560	of_node_put(pa->pdev.dev.of_node);
 561	kfree(pa->pdev.dev.platform_data);
 562	kfree(pa->pdev.mfd_cell);
 563	kfree(pa->pdev.resource);
 564	kfree(pa->pdev.driver_override);
 565	kfree(pa);
 566}
 567
 568/**
 569 * platform_device_alloc - create a platform device
 570 * @name: base name of the device we're adding
 571 * @id: instance id
 572 *
 573 * Create a platform device object which can have other objects attached
 574 * to it, and which will have attached objects freed when it is released.
 575 */
 576struct platform_device *platform_device_alloc(const char *name, int id)
 577{
 578	struct platform_object *pa;
 579
 580	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 581	if (pa) {
 582		strcpy(pa->name, name);
 583		pa->pdev.name = pa->name;
 584		pa->pdev.id = id;
 585		device_initialize(&pa->pdev.dev);
 586		pa->pdev.dev.release = platform_device_release;
 587		setup_pdev_dma_masks(&pa->pdev);
 588	}
 589
 590	return pa ? &pa->pdev : NULL;
 591}
 592EXPORT_SYMBOL_GPL(platform_device_alloc);
 593
 594/**
 595 * platform_device_add_resources - add resources to a platform device
 596 * @pdev: platform device allocated by platform_device_alloc to add resources to
 597 * @res: set of resources that needs to be allocated for the device
 598 * @num: number of resources
 599 *
 600 * Add a copy of the resources to the platform device.  The memory
 601 * associated with the resources will be freed when the platform device is
 602 * released.
 603 */
 604int platform_device_add_resources(struct platform_device *pdev,
 605				  const struct resource *res, unsigned int num)
 606{
 607	struct resource *r = NULL;
 608
 609	if (res) {
 610		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 611		if (!r)
 612			return -ENOMEM;
 613	}
 614
 615	kfree(pdev->resource);
 616	pdev->resource = r;
 617	pdev->num_resources = num;
 618	return 0;
 619}
 620EXPORT_SYMBOL_GPL(platform_device_add_resources);
 621
 622/**
 623 * platform_device_add_data - add platform-specific data to a platform device
 624 * @pdev: platform device allocated by platform_device_alloc to add resources to
 625 * @data: platform specific data for this platform device
 626 * @size: size of platform specific data
 627 *
 628 * Add a copy of platform specific data to the platform device's
 629 * platform_data pointer.  The memory associated with the platform data
 630 * will be freed when the platform device is released.
 631 */
 632int platform_device_add_data(struct platform_device *pdev, const void *data,
 633			     size_t size)
 634{
 635	void *d = NULL;
 636
 637	if (data) {
 638		d = kmemdup(data, size, GFP_KERNEL);
 639		if (!d)
 640			return -ENOMEM;
 641	}
 642
 643	kfree(pdev->dev.platform_data);
 644	pdev->dev.platform_data = d;
 645	return 0;
 646}
 647EXPORT_SYMBOL_GPL(platform_device_add_data);
 648
 649/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 650 * platform_device_add - add a platform device to device hierarchy
 651 * @pdev: platform device we're adding
 652 *
 653 * This is part 2 of platform_device_register(), though may be called
 654 * separately _iff_ pdev was allocated by platform_device_alloc().
 655 */
 656int platform_device_add(struct platform_device *pdev)
 657{
 658	u32 i;
 659	int ret;
 660
 661	if (!pdev)
 662		return -EINVAL;
 663
 664	if (!pdev->dev.parent)
 665		pdev->dev.parent = &platform_bus;
 666
 667	pdev->dev.bus = &platform_bus_type;
 668
 669	switch (pdev->id) {
 670	default:
 671		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 672		break;
 673	case PLATFORM_DEVID_NONE:
 674		dev_set_name(&pdev->dev, "%s", pdev->name);
 675		break;
 676	case PLATFORM_DEVID_AUTO:
 677		/*
 678		 * Automatically allocated device ID. We mark it as such so
 679		 * that we remember it must be freed, and we append a suffix
 680		 * to avoid namespace collision with explicit IDs.
 681		 */
 682		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
 683		if (ret < 0)
 684			goto err_out;
 685		pdev->id = ret;
 686		pdev->id_auto = true;
 687		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 688		break;
 689	}
 690
 691	for (i = 0; i < pdev->num_resources; i++) {
 692		struct resource *p, *r = &pdev->resource[i];
 693
 694		if (r->name == NULL)
 695			r->name = dev_name(&pdev->dev);
 696
 697		p = r->parent;
 698		if (!p) {
 699			if (resource_type(r) == IORESOURCE_MEM)
 700				p = &iomem_resource;
 701			else if (resource_type(r) == IORESOURCE_IO)
 702				p = &ioport_resource;
 703		}
 704
 705		if (p) {
 706			ret = insert_resource(p, r);
 707			if (ret) {
 708				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 709				goto failed;
 710			}
 711		}
 712	}
 713
 714	pr_debug("Registering platform device '%s'. Parent at %s\n",
 715		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 716
 717	ret = device_add(&pdev->dev);
 718	if (ret == 0)
 719		return ret;
 720
 721 failed:
 722	if (pdev->id_auto) {
 723		ida_free(&platform_devid_ida, pdev->id);
 724		pdev->id = PLATFORM_DEVID_AUTO;
 725	}
 726
 727	while (i--) {
 728		struct resource *r = &pdev->resource[i];
 729		if (r->parent)
 730			release_resource(r);
 731	}
 732
 733 err_out:
 734	return ret;
 735}
 736EXPORT_SYMBOL_GPL(platform_device_add);
 737
 738/**
 739 * platform_device_del - remove a platform-level device
 740 * @pdev: platform device we're removing
 741 *
 742 * Note that this function will also release all memory- and port-based
 743 * resources owned by the device (@dev->resource).  This function must
 744 * _only_ be externally called in error cases.  All other usage is a bug.
 745 */
 746void platform_device_del(struct platform_device *pdev)
 747{
 748	u32 i;
 749
 750	if (!IS_ERR_OR_NULL(pdev)) {
 
 751		device_del(&pdev->dev);
 752
 753		if (pdev->id_auto) {
 754			ida_free(&platform_devid_ida, pdev->id);
 755			pdev->id = PLATFORM_DEVID_AUTO;
 756		}
 757
 758		for (i = 0; i < pdev->num_resources; i++) {
 759			struct resource *r = &pdev->resource[i];
 760			if (r->parent)
 761				release_resource(r);
 762		}
 763	}
 764}
 765EXPORT_SYMBOL_GPL(platform_device_del);
 766
 767/**
 768 * platform_device_register - add a platform-level device
 769 * @pdev: platform device we're adding
 770 *
 771 * NOTE: _Never_ directly free @pdev after calling this function, even if it
 772 * returned an error! Always use platform_device_put() to give up the
 773 * reference initialised in this function instead.
 774 */
 775int platform_device_register(struct platform_device *pdev)
 776{
 777	device_initialize(&pdev->dev);
 778	setup_pdev_dma_masks(pdev);
 779	return platform_device_add(pdev);
 780}
 781EXPORT_SYMBOL_GPL(platform_device_register);
 782
 783/**
 784 * platform_device_unregister - unregister a platform-level device
 785 * @pdev: platform device we're unregistering
 786 *
 787 * Unregistration is done in 2 steps. First we release all resources
 788 * and remove it from the subsystem, then we drop reference count by
 789 * calling platform_device_put().
 790 */
 791void platform_device_unregister(struct platform_device *pdev)
 792{
 793	platform_device_del(pdev);
 794	platform_device_put(pdev);
 795}
 796EXPORT_SYMBOL_GPL(platform_device_unregister);
 797
 798/**
 799 * platform_device_register_full - add a platform-level device with
 800 * resources and platform-specific data
 801 *
 802 * @pdevinfo: data used to create device
 803 *
 804 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 805 */
 806struct platform_device *platform_device_register_full(
 807		const struct platform_device_info *pdevinfo)
 808{
 809	int ret;
 810	struct platform_device *pdev;
 811
 812	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 813	if (!pdev)
 814		return ERR_PTR(-ENOMEM);
 815
 816	pdev->dev.parent = pdevinfo->parent;
 817	pdev->dev.fwnode = pdevinfo->fwnode;
 818	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
 819	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
 820
 821	if (pdevinfo->dma_mask) {
 822		pdev->platform_dma_mask = pdevinfo->dma_mask;
 823		pdev->dev.dma_mask = &pdev->platform_dma_mask;
 
 
 
 
 
 
 
 
 
 
 824		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 825	}
 826
 827	ret = platform_device_add_resources(pdev,
 828			pdevinfo->res, pdevinfo->num_res);
 829	if (ret)
 830		goto err;
 831
 832	ret = platform_device_add_data(pdev,
 833			pdevinfo->data, pdevinfo->size_data);
 834	if (ret)
 835		goto err;
 836
 837	if (pdevinfo->properties) {
 838		ret = device_create_managed_software_node(&pdev->dev,
 839							  pdevinfo->properties, NULL);
 840		if (ret)
 841			goto err;
 842	}
 843
 844	ret = platform_device_add(pdev);
 845	if (ret) {
 846err:
 847		ACPI_COMPANION_SET(&pdev->dev, NULL);
 
 
 
 848		platform_device_put(pdev);
 849		return ERR_PTR(ret);
 850	}
 851
 852	return pdev;
 853}
 854EXPORT_SYMBOL_GPL(platform_device_register_full);
 855
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 856/**
 857 * __platform_driver_register - register a driver for platform-level devices
 858 * @drv: platform driver structure
 859 * @owner: owning module/driver
 860 */
 861int __platform_driver_register(struct platform_driver *drv,
 862				struct module *owner)
 863{
 864	drv->driver.owner = owner;
 865	drv->driver.bus = &platform_bus_type;
 
 
 
 866
 867	return driver_register(&drv->driver);
 868}
 869EXPORT_SYMBOL_GPL(__platform_driver_register);
 870
 871/**
 872 * platform_driver_unregister - unregister a driver for platform-level devices
 873 * @drv: platform driver structure
 874 */
 875void platform_driver_unregister(struct platform_driver *drv)
 876{
 877	driver_unregister(&drv->driver);
 878}
 879EXPORT_SYMBOL_GPL(platform_driver_unregister);
 880
 881static int platform_probe_fail(struct platform_device *pdev)
 882{
 883	return -ENXIO;
 884}
 885
 886/**
 887 * __platform_driver_probe - register driver for non-hotpluggable device
 888 * @drv: platform driver structure
 889 * @probe: the driver probe routine, probably from an __init section
 890 * @module: module which will be the owner of the driver
 891 *
 892 * Use this instead of platform_driver_register() when you know the device
 893 * is not hotpluggable and has already been registered, and you want to
 894 * remove its run-once probe() infrastructure from memory after the driver
 895 * has bound to the device.
 896 *
 897 * One typical use for this would be with drivers for controllers integrated
 898 * into system-on-chip processors, where the controller devices have been
 899 * configured as part of board setup.
 900 *
 901 * Note that this is incompatible with deferred probing.
 902 *
 903 * Returns zero if the driver registered and bound to a device, else returns
 904 * a negative error code and with the driver not registered.
 905 */
 906int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 907		int (*probe)(struct platform_device *), struct module *module)
 908{
 909	int retval, code;
 910
 911	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 912		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 913			 drv->driver.name, __func__);
 914		return -EINVAL;
 915	}
 916
 917	/*
 918	 * We have to run our probes synchronously because we check if
 919	 * we find any devices to bind to and exit with error if there
 920	 * are any.
 921	 */
 922	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 923
 924	/*
 925	 * Prevent driver from requesting probe deferral to avoid further
 926	 * futile probe attempts.
 927	 */
 928	drv->prevent_deferred_probe = true;
 929
 930	/* make sure driver won't have bind/unbind attributes */
 931	drv->driver.suppress_bind_attrs = true;
 932
 933	/* temporary section violation during probe() */
 934	drv->probe = probe;
 935	retval = code = __platform_driver_register(drv, module);
 936	if (retval)
 937		return retval;
 938
 939	/*
 940	 * Fixup that section violation, being paranoid about code scanning
 941	 * the list of drivers in order to probe new devices.  Check to see
 942	 * if the probe was successful, and make sure any forced probes of
 943	 * new devices fail.
 944	 */
 945	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 946	drv->probe = platform_probe_fail;
 947	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 948		retval = -ENODEV;
 
 949	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 950
 951	if (code != retval)
 952		platform_driver_unregister(drv);
 953	return retval;
 954}
 955EXPORT_SYMBOL_GPL(__platform_driver_probe);
 956
 957/**
 958 * __platform_create_bundle - register driver and create corresponding device
 959 * @driver: platform driver structure
 960 * @probe: the driver probe routine, probably from an __init section
 961 * @res: set of resources that needs to be allocated for the device
 962 * @n_res: number of resources
 963 * @data: platform specific data for this platform device
 964 * @size: size of platform specific data
 965 * @module: module which will be the owner of the driver
 966 *
 967 * Use this in legacy-style modules that probe hardware directly and
 968 * register a single platform device and corresponding platform driver.
 969 *
 970 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 971 */
 972struct platform_device * __init_or_module __platform_create_bundle(
 973			struct platform_driver *driver,
 974			int (*probe)(struct platform_device *),
 975			struct resource *res, unsigned int n_res,
 976			const void *data, size_t size, struct module *module)
 977{
 978	struct platform_device *pdev;
 979	int error;
 980
 981	pdev = platform_device_alloc(driver->driver.name, -1);
 982	if (!pdev) {
 983		error = -ENOMEM;
 984		goto err_out;
 985	}
 986
 987	error = platform_device_add_resources(pdev, res, n_res);
 988	if (error)
 989		goto err_pdev_put;
 990
 991	error = platform_device_add_data(pdev, data, size);
 992	if (error)
 993		goto err_pdev_put;
 994
 995	error = platform_device_add(pdev);
 996	if (error)
 997		goto err_pdev_put;
 998
 999	error = __platform_driver_probe(driver, probe, module);
1000	if (error)
1001		goto err_pdev_del;
1002
1003	return pdev;
1004
1005err_pdev_del:
1006	platform_device_del(pdev);
1007err_pdev_put:
1008	platform_device_put(pdev);
1009err_out:
1010	return ERR_PTR(error);
1011}
1012EXPORT_SYMBOL_GPL(__platform_create_bundle);
1013
1014/**
1015 * __platform_register_drivers - register an array of platform drivers
1016 * @drivers: an array of drivers to register
1017 * @count: the number of drivers to register
1018 * @owner: module owning the drivers
1019 *
1020 * Registers platform drivers specified by an array. On failure to register a
1021 * driver, all previously registered drivers will be unregistered. Callers of
1022 * this API should use platform_unregister_drivers() to unregister drivers in
1023 * the reverse order.
1024 *
1025 * Returns: 0 on success or a negative error code on failure.
1026 */
1027int __platform_register_drivers(struct platform_driver * const *drivers,
1028				unsigned int count, struct module *owner)
1029{
1030	unsigned int i;
1031	int err;
1032
1033	for (i = 0; i < count; i++) {
1034		pr_debug("registering platform driver %ps\n", drivers[i]);
1035
1036		err = __platform_driver_register(drivers[i], owner);
1037		if (err < 0) {
1038			pr_err("failed to register platform driver %ps: %d\n",
1039			       drivers[i], err);
1040			goto error;
1041		}
1042	}
1043
1044	return 0;
1045
1046error:
1047	while (i--) {
1048		pr_debug("unregistering platform driver %ps\n", drivers[i]);
1049		platform_driver_unregister(drivers[i]);
1050	}
1051
1052	return err;
1053}
1054EXPORT_SYMBOL_GPL(__platform_register_drivers);
1055
1056/**
1057 * platform_unregister_drivers - unregister an array of platform drivers
1058 * @drivers: an array of drivers to unregister
1059 * @count: the number of drivers to unregister
1060 *
1061 * Unregisters platform drivers specified by an array. This is typically used
1062 * to complement an earlier call to platform_register_drivers(). Drivers are
1063 * unregistered in the reverse order in which they were registered.
1064 */
1065void platform_unregister_drivers(struct platform_driver * const *drivers,
1066				 unsigned int count)
1067{
1068	while (count--) {
1069		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1070		platform_driver_unregister(drivers[count]);
1071	}
1072}
1073EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1074
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1075static const struct platform_device_id *platform_match_id(
1076			const struct platform_device_id *id,
1077			struct platform_device *pdev)
1078{
1079	while (id->name[0]) {
1080		if (strcmp(pdev->name, id->name) == 0) {
1081			pdev->id_entry = id;
1082			return id;
1083		}
1084		id++;
1085	}
1086	return NULL;
1087}
1088
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1089#ifdef CONFIG_PM_SLEEP
1090
1091static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1092{
1093	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1094	struct platform_device *pdev = to_platform_device(dev);
1095	int ret = 0;
1096
1097	if (dev->driver && pdrv->suspend)
1098		ret = pdrv->suspend(pdev, mesg);
1099
1100	return ret;
1101}
1102
1103static int platform_legacy_resume(struct device *dev)
1104{
1105	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1106	struct platform_device *pdev = to_platform_device(dev);
1107	int ret = 0;
1108
1109	if (dev->driver && pdrv->resume)
1110		ret = pdrv->resume(pdev);
1111
1112	return ret;
1113}
1114
1115#endif /* CONFIG_PM_SLEEP */
1116
1117#ifdef CONFIG_SUSPEND
1118
1119int platform_pm_suspend(struct device *dev)
1120{
1121	struct device_driver *drv = dev->driver;
1122	int ret = 0;
1123
1124	if (!drv)
1125		return 0;
1126
1127	if (drv->pm) {
1128		if (drv->pm->suspend)
1129			ret = drv->pm->suspend(dev);
1130	} else {
1131		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1132	}
1133
1134	return ret;
1135}
1136
1137int platform_pm_resume(struct device *dev)
1138{
1139	struct device_driver *drv = dev->driver;
1140	int ret = 0;
1141
1142	if (!drv)
1143		return 0;
1144
1145	if (drv->pm) {
1146		if (drv->pm->resume)
1147			ret = drv->pm->resume(dev);
1148	} else {
1149		ret = platform_legacy_resume(dev);
1150	}
1151
1152	return ret;
1153}
1154
1155#endif /* CONFIG_SUSPEND */
1156
1157#ifdef CONFIG_HIBERNATE_CALLBACKS
1158
1159int platform_pm_freeze(struct device *dev)
1160{
1161	struct device_driver *drv = dev->driver;
1162	int ret = 0;
1163
1164	if (!drv)
1165		return 0;
1166
1167	if (drv->pm) {
1168		if (drv->pm->freeze)
1169			ret = drv->pm->freeze(dev);
1170	} else {
1171		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1172	}
1173
1174	return ret;
1175}
1176
1177int platform_pm_thaw(struct device *dev)
1178{
1179	struct device_driver *drv = dev->driver;
1180	int ret = 0;
1181
1182	if (!drv)
1183		return 0;
1184
1185	if (drv->pm) {
1186		if (drv->pm->thaw)
1187			ret = drv->pm->thaw(dev);
1188	} else {
1189		ret = platform_legacy_resume(dev);
1190	}
1191
1192	return ret;
1193}
1194
1195int platform_pm_poweroff(struct device *dev)
1196{
1197	struct device_driver *drv = dev->driver;
1198	int ret = 0;
1199
1200	if (!drv)
1201		return 0;
1202
1203	if (drv->pm) {
1204		if (drv->pm->poweroff)
1205			ret = drv->pm->poweroff(dev);
1206	} else {
1207		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1208	}
1209
1210	return ret;
1211}
1212
1213int platform_pm_restore(struct device *dev)
1214{
1215	struct device_driver *drv = dev->driver;
1216	int ret = 0;
1217
1218	if (!drv)
1219		return 0;
1220
1221	if (drv->pm) {
1222		if (drv->pm->restore)
1223			ret = drv->pm->restore(dev);
1224	} else {
1225		ret = platform_legacy_resume(dev);
1226	}
1227
1228	return ret;
1229}
1230
1231#endif /* CONFIG_HIBERNATE_CALLBACKS */
1232
1233/* modalias support enables more hands-off userspace setup:
1234 * (a) environment variable lets new-style hotplug events work once system is
1235 *     fully running:  "modprobe $MODALIAS"
1236 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1237 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1238 */
1239static ssize_t modalias_show(struct device *dev,
1240			     struct device_attribute *attr, char *buf)
1241{
1242	struct platform_device *pdev = to_platform_device(dev);
1243	int len;
1244
1245	len = of_device_modalias(dev, buf, PAGE_SIZE);
1246	if (len != -ENODEV)
1247		return len;
1248
1249	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1250	if (len != -ENODEV)
1251		return len;
1252
1253	return sysfs_emit(buf, "platform:%s\n", pdev->name);
1254}
1255static DEVICE_ATTR_RO(modalias);
1256
1257static ssize_t numa_node_show(struct device *dev,
1258			      struct device_attribute *attr, char *buf)
1259{
1260	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1261}
1262static DEVICE_ATTR_RO(numa_node);
1263
1264static ssize_t driver_override_show(struct device *dev,
1265				    struct device_attribute *attr, char *buf)
1266{
1267	struct platform_device *pdev = to_platform_device(dev);
1268	ssize_t len;
1269
1270	device_lock(dev);
1271	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1272	device_unlock(dev);
1273
1274	return len;
1275}
 
 
 
 
 
 
 
1276
1277static ssize_t driver_override_store(struct device *dev,
1278				     struct device_attribute *attr,
1279				     const char *buf, size_t count)
1280{
1281	struct platform_device *pdev = to_platform_device(dev);
1282	int ret;
1283
1284	ret = driver_set_override(dev, &pdev->driver_override, buf, count);
1285	if (ret)
1286		return ret;
1287
1288	return count;
 
 
 
 
 
 
 
 
 
1289}
1290static DEVICE_ATTR_RW(driver_override);
1291
1292static struct attribute *platform_dev_attrs[] = {
1293	&dev_attr_modalias.attr,
1294	&dev_attr_numa_node.attr,
1295	&dev_attr_driver_override.attr,
1296	NULL,
1297};
1298
1299static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1300		int n)
1301{
1302	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1303
1304	if (a == &dev_attr_numa_node.attr &&
1305			dev_to_node(dev) == NUMA_NO_NODE)
1306		return 0;
1307
1308	return a->mode;
 
 
 
 
 
 
 
 
1309}
 
 
1310
1311static const struct attribute_group platform_dev_group = {
1312	.attrs = platform_dev_attrs,
1313	.is_visible = platform_dev_attrs_visible,
1314};
1315__ATTRIBUTE_GROUPS(platform_dev);
1316
1317
1318/**
1319 * platform_match - bind platform device to platform driver.
1320 * @dev: device.
1321 * @drv: driver.
1322 *
1323 * Platform device IDs are assumed to be encoded like this:
1324 * "<name><instance>", where <name> is a short description of the type of
1325 * device, like "pci" or "floppy", and <instance> is the enumerated
1326 * instance of the device, like '0' or '42'.  Driver IDs are simply
1327 * "<name>".  So, extract the <name> from the platform_device structure,
1328 * and compare it against the name of the driver. Return whether they match
1329 * or not.
1330 */
1331static int platform_match(struct device *dev, struct device_driver *drv)
 
1332{
1333	struct platform_device *pdev = to_platform_device(dev);
1334	struct platform_driver *pdrv = to_platform_driver(drv);
1335
1336	/* When driver_override is set, only bind to the matching driver */
1337	if (pdev->driver_override)
1338		return !strcmp(pdev->driver_override, drv->name);
 
 
 
 
1339
1340	/* Attempt an OF style match first */
1341	if (of_driver_match_device(dev, drv))
1342		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1343
1344	/* Then try ACPI style match */
1345	if (acpi_driver_match_device(dev, drv))
1346		return 1;
1347
1348	/* Then try to match against the id table */
1349	if (pdrv->id_table)
1350		return platform_match_id(pdrv->id_table, pdev) != NULL;
 
 
 
1351
1352	/* fall-back to driver name match */
1353	return (strcmp(pdev->name, drv->name) == 0);
1354}
1355
1356static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 
 
 
 
 
 
 
 
1357{
1358	struct platform_device	*pdev = to_platform_device(dev);
1359	int rc;
1360
1361	/* Some devices have extra OF data and an OF-style MODALIAS */
1362	rc = of_device_uevent_modalias(dev, env);
1363	if (rc != -ENODEV)
1364		return rc;
1365
1366	rc = acpi_device_uevent_modalias(dev, env);
1367	if (rc != -ENODEV)
1368		return rc;
1369
1370	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1371			pdev->name);
1372	return 0;
 
 
 
 
1373}
1374
1375static int platform_probe(struct device *_dev)
1376{
1377	struct platform_driver *drv = to_platform_driver(_dev->driver);
1378	struct platform_device *dev = to_platform_device(_dev);
1379	int ret;
1380
1381	/*
1382	 * A driver registered using platform_driver_probe() cannot be bound
1383	 * again later because the probe function usually lives in __init code
1384	 * and so is gone. For these drivers .probe is set to
1385	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1386	 * clocks and PM domains for these to match the traditional behaviour.
 
 
 
 
 
 
 
 
 
 
 
1387	 */
1388	if (unlikely(drv->probe == platform_probe_fail))
1389		return -ENXIO;
1390
1391	ret = of_clk_set_defaults(_dev->of_node, false);
1392	if (ret < 0)
1393		return ret;
1394
1395	ret = dev_pm_domain_attach(_dev, true);
1396	if (ret)
1397		goto out;
1398
1399	if (drv->probe) {
1400		ret = drv->probe(dev);
1401		if (ret)
1402			dev_pm_domain_detach(_dev, true);
1403	}
 
 
 
 
1404
1405out:
1406	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1407		dev_warn(_dev, "probe deferral not supported\n");
1408		ret = -ENXIO;
1409	}
1410
1411	return ret;
1412}
1413
1414static void platform_remove(struct device *_dev)
1415{
1416	struct platform_driver *drv = to_platform_driver(_dev->driver);
1417	struct platform_device *dev = to_platform_device(_dev);
1418
1419	if (drv->remove) {
1420		int ret = drv->remove(dev);
 
 
 
 
 
 
 
1421
1422		if (ret)
1423			dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1424	}
1425	dev_pm_domain_detach(_dev, true);
1426}
1427
1428static void platform_shutdown(struct device *_dev)
1429{
1430	struct platform_device *dev = to_platform_device(_dev);
1431	struct platform_driver *drv;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1432
1433	if (!_dev->driver)
1434		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1435
1436	drv = to_platform_driver(_dev->driver);
1437	if (drv->shutdown)
1438		drv->shutdown(dev);
1439}
 
 
 
 
 
 
 
1440
1441static int platform_dma_configure(struct device *dev)
1442{
1443	struct platform_driver *drv = to_platform_driver(dev->driver);
1444	enum dev_dma_attr attr;
1445	int ret = 0;
 
 
 
 
 
 
 
 
 
 
 
1446
1447	if (dev->of_node) {
1448		ret = of_dma_configure(dev, dev->of_node, true);
1449	} else if (has_acpi_companion(dev)) {
1450		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1451		ret = acpi_dma_configure(dev, attr);
1452	}
1453
1454	if (!ret && !drv->driver_managed_dma) {
1455		ret = iommu_device_use_default_domain(dev);
1456		if (ret)
1457			arch_teardown_dma_ops(dev);
 
 
 
 
 
1458	}
1459
1460	return ret;
 
 
 
1461}
1462
1463static void platform_dma_cleanup(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
1464{
1465	struct platform_driver *drv = to_platform_driver(dev->driver);
1466
1467	if (!drv->driver_managed_dma)
1468		iommu_device_unuse_default_domain(dev);
1469}
1470
1471static const struct dev_pm_ops platform_dev_pm_ops = {
1472	SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
1473	USE_PLATFORM_PM_SLEEP_OPS
1474};
1475
1476struct bus_type platform_bus_type = {
1477	.name		= "platform",
1478	.dev_groups	= platform_dev_groups,
1479	.match		= platform_match,
1480	.uevent		= platform_uevent,
1481	.probe		= platform_probe,
1482	.remove		= platform_remove,
1483	.shutdown	= platform_shutdown,
1484	.dma_configure	= platform_dma_configure,
1485	.dma_cleanup	= platform_dma_cleanup,
1486	.pm		= &platform_dev_pm_ops,
1487};
1488EXPORT_SYMBOL_GPL(platform_bus_type);
1489
1490static inline int __platform_match(struct device *dev, const void *drv)
1491{
1492	return platform_match(dev, (struct device_driver *)drv);
 
 
1493}
1494
1495/**
1496 * platform_find_device_by_driver - Find a platform device with a given
1497 * driver.
1498 * @start: The device to start the search from.
1499 * @drv: The device driver to look for.
1500 */
1501struct device *platform_find_device_by_driver(struct device *start,
1502					      const struct device_driver *drv)
1503{
1504	return bus_find_device(&platform_bus_type, start, drv,
1505			       __platform_match);
1506}
1507EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1508
1509void __weak __init early_platform_cleanup(void) { }
1510
1511int __init platform_bus_init(void)
1512{
1513	int error;
1514
1515	early_platform_cleanup();
1516
1517	error = device_register(&platform_bus);
1518	if (error) {
1519		put_device(&platform_bus);
1520		return error;
1521	}
1522	error =  bus_register(&platform_bus_type);
1523	if (error)
1524		device_unregister(&platform_bus);
1525	of_platform_register_reconfig_notifier();
1526	return error;
1527}
v4.17
   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-model/platform.txt 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/bootmem.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
  30#include "base.h"
  31#include "power/power.h"
  32
  33/* For automatically allocated device IDs */
  34static DEFINE_IDA(platform_devid_ida);
  35
  36struct device platform_bus = {
  37	.init_name	= "platform",
  38};
  39EXPORT_SYMBOL_GPL(platform_bus);
  40
  41/**
  42 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  43 * @pdev: platform device
  44 *
  45 * This is called before platform_device_add() such that any pdev_archdata may
  46 * be setup before the platform_notifier is called.  So if a user needs to
  47 * manipulate any relevant information in the pdev_archdata they can do:
  48 *
  49 *	platform_device_alloc()
  50 *	... manipulate ...
  51 *	platform_device_add()
  52 *
  53 * And if they don't care they can just call platform_device_register() and
  54 * everything will just work out.
  55 */
  56void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  57{
  58}
  59
  60/**
  61 * platform_get_resource - get a resource for a device
  62 * @dev: platform device
  63 * @type: resource type
  64 * @num: resource index
 
 
  65 */
  66struct resource *platform_get_resource(struct platform_device *dev,
  67				       unsigned int type, unsigned int num)
  68{
  69	int i;
  70
  71	for (i = 0; i < dev->num_resources; i++) {
  72		struct resource *r = &dev->resource[i];
  73
  74		if (type == resource_type(r) && num-- == 0)
  75			return r;
  76	}
  77	return NULL;
  78}
  79EXPORT_SYMBOL_GPL(platform_get_resource);
  80
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  81/**
  82 * platform_get_irq - get an IRQ for a device
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  83 * @dev: platform device
  84 * @num: IRQ number index
 
 
 
 
 
 
 
 
 
 
 
 
 
  85 */
  86int platform_get_irq(struct platform_device *dev, unsigned int num)
  87{
 
  88#ifdef CONFIG_SPARC
  89	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
  90	if (!dev || num >= dev->archdata.num_irqs)
  91		return -ENXIO;
  92	return dev->archdata.irqs[num];
 
  93#else
  94	struct resource *r;
 
  95	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
  96		int ret;
  97
  98		ret = of_irq_get(dev->dev.of_node, num);
  99		if (ret > 0 || ret == -EPROBE_DEFER)
 100			return ret;
 101	}
 102
 103	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 104	if (has_acpi_companion(&dev->dev)) {
 105		if (r && r->flags & IORESOURCE_DISABLED) {
 106			int ret;
 107
 108			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 109			if (ret)
 110				return ret;
 111		}
 112	}
 113
 114	/*
 115	 * The resources may pass trigger flags to the irqs that need
 116	 * to be set up. It so happens that the trigger flags for
 117	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 118	 * settings.
 119	 */
 120	if (r && r->flags & IORESOURCE_BITS) {
 121		struct irq_data *irqd;
 122
 123		irqd = irq_get_irq_data(r->start);
 124		if (!irqd)
 125			return -ENXIO;
 126		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 127	}
 128
 129	return r ? r->start : -ENXIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 130#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 131}
 132EXPORT_SYMBOL_GPL(platform_get_irq);
 133
 134/**
 135 * platform_irq_count - Count the number of IRQs a platform device uses
 136 * @dev: platform device
 137 *
 138 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 139 */
 140int platform_irq_count(struct platform_device *dev)
 141{
 142	int ret, nr = 0;
 143
 144	while ((ret = platform_get_irq(dev, nr)) >= 0)
 145		nr++;
 146
 147	if (ret == -EPROBE_DEFER)
 148		return ret;
 149
 150	return nr;
 151}
 152EXPORT_SYMBOL_GPL(platform_irq_count);
 153
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 154/**
 155 * platform_get_resource_byname - get a resource for a device by name
 156 * @dev: platform device
 157 * @type: resource type
 158 * @name: resource name
 159 */
 160struct resource *platform_get_resource_byname(struct platform_device *dev,
 161					      unsigned int type,
 162					      const char *name)
 163{
 164	int i;
 165
 166	for (i = 0; i < dev->num_resources; i++) {
 167		struct resource *r = &dev->resource[i];
 168
 169		if (unlikely(!r->name))
 170			continue;
 171
 172		if (type == resource_type(r) && !strcmp(r->name, name))
 173			return r;
 174	}
 175	return NULL;
 176}
 177EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 178
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 179/**
 180 * platform_get_irq_byname - get an IRQ for a device by name
 181 * @dev: platform device
 182 * @name: IRQ name
 
 
 
 
 183 */
 184int platform_get_irq_byname(struct platform_device *dev, const char *name)
 185{
 186	struct resource *r;
 187
 188	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 189		int ret;
 
 
 
 
 
 190
 191		ret = of_irq_get_byname(dev->dev.of_node, name);
 192		if (ret > 0 || ret == -EPROBE_DEFER)
 193			return ret;
 194	}
 195
 196	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 197	return r ? r->start : -ENXIO;
 
 
 
 
 
 
 
 198}
 199EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 200
 201/**
 202 * platform_add_devices - add a numbers of platform devices
 203 * @devs: array of platform devices to add
 204 * @num: number of platform devices in array
 205 */
 206int platform_add_devices(struct platform_device **devs, int num)
 207{
 208	int i, ret = 0;
 209
 210	for (i = 0; i < num; i++) {
 211		ret = platform_device_register(devs[i]);
 212		if (ret) {
 213			while (--i >= 0)
 214				platform_device_unregister(devs[i]);
 215			break;
 216		}
 217	}
 218
 219	return ret;
 220}
 221EXPORT_SYMBOL_GPL(platform_add_devices);
 222
 223struct platform_object {
 224	struct platform_device pdev;
 225	char name[];
 226};
 227
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 228/**
 229 * platform_device_put - destroy a platform device
 230 * @pdev: platform device to free
 231 *
 232 * Free all memory associated with a platform device.  This function must
 233 * _only_ be externally called in error cases.  All other usage is a bug.
 234 */
 235void platform_device_put(struct platform_device *pdev)
 236{
 237	if (pdev)
 238		put_device(&pdev->dev);
 239}
 240EXPORT_SYMBOL_GPL(platform_device_put);
 241
 242static void platform_device_release(struct device *dev)
 243{
 244	struct platform_object *pa = container_of(dev, struct platform_object,
 245						  pdev.dev);
 246
 247	of_device_node_put(&pa->pdev.dev);
 248	kfree(pa->pdev.dev.platform_data);
 249	kfree(pa->pdev.mfd_cell);
 250	kfree(pa->pdev.resource);
 251	kfree(pa->pdev.driver_override);
 252	kfree(pa);
 253}
 254
 255/**
 256 * platform_device_alloc - create a platform device
 257 * @name: base name of the device we're adding
 258 * @id: instance id
 259 *
 260 * Create a platform device object which can have other objects attached
 261 * to it, and which will have attached objects freed when it is released.
 262 */
 263struct platform_device *platform_device_alloc(const char *name, int id)
 264{
 265	struct platform_object *pa;
 266
 267	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 268	if (pa) {
 269		strcpy(pa->name, name);
 270		pa->pdev.name = pa->name;
 271		pa->pdev.id = id;
 272		device_initialize(&pa->pdev.dev);
 273		pa->pdev.dev.release = platform_device_release;
 274		arch_setup_pdev_archdata(&pa->pdev);
 275	}
 276
 277	return pa ? &pa->pdev : NULL;
 278}
 279EXPORT_SYMBOL_GPL(platform_device_alloc);
 280
 281/**
 282 * platform_device_add_resources - add resources to a platform device
 283 * @pdev: platform device allocated by platform_device_alloc to add resources to
 284 * @res: set of resources that needs to be allocated for the device
 285 * @num: number of resources
 286 *
 287 * Add a copy of the resources to the platform device.  The memory
 288 * associated with the resources will be freed when the platform device is
 289 * released.
 290 */
 291int platform_device_add_resources(struct platform_device *pdev,
 292				  const struct resource *res, unsigned int num)
 293{
 294	struct resource *r = NULL;
 295
 296	if (res) {
 297		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 298		if (!r)
 299			return -ENOMEM;
 300	}
 301
 302	kfree(pdev->resource);
 303	pdev->resource = r;
 304	pdev->num_resources = num;
 305	return 0;
 306}
 307EXPORT_SYMBOL_GPL(platform_device_add_resources);
 308
 309/**
 310 * platform_device_add_data - add platform-specific data to a platform device
 311 * @pdev: platform device allocated by platform_device_alloc to add resources to
 312 * @data: platform specific data for this platform device
 313 * @size: size of platform specific data
 314 *
 315 * Add a copy of platform specific data to the platform device's
 316 * platform_data pointer.  The memory associated with the platform data
 317 * will be freed when the platform device is released.
 318 */
 319int platform_device_add_data(struct platform_device *pdev, const void *data,
 320			     size_t size)
 321{
 322	void *d = NULL;
 323
 324	if (data) {
 325		d = kmemdup(data, size, GFP_KERNEL);
 326		if (!d)
 327			return -ENOMEM;
 328	}
 329
 330	kfree(pdev->dev.platform_data);
 331	pdev->dev.platform_data = d;
 332	return 0;
 333}
 334EXPORT_SYMBOL_GPL(platform_device_add_data);
 335
 336/**
 337 * platform_device_add_properties - add built-in properties to a platform device
 338 * @pdev: platform device to add properties to
 339 * @properties: null terminated array of properties to add
 340 *
 341 * The function will take deep copy of @properties and attach the copy to the
 342 * platform device. The memory associated with properties will be freed when the
 343 * platform device is released.
 344 */
 345int platform_device_add_properties(struct platform_device *pdev,
 346				   const struct property_entry *properties)
 347{
 348	return device_add_properties(&pdev->dev, properties);
 349}
 350EXPORT_SYMBOL_GPL(platform_device_add_properties);
 351
 352/**
 353 * platform_device_add - add a platform device to device hierarchy
 354 * @pdev: platform device we're adding
 355 *
 356 * This is part 2 of platform_device_register(), though may be called
 357 * separately _iff_ pdev was allocated by platform_device_alloc().
 358 */
 359int platform_device_add(struct platform_device *pdev)
 360{
 361	int i, ret;
 
 362
 363	if (!pdev)
 364		return -EINVAL;
 365
 366	if (!pdev->dev.parent)
 367		pdev->dev.parent = &platform_bus;
 368
 369	pdev->dev.bus = &platform_bus_type;
 370
 371	switch (pdev->id) {
 372	default:
 373		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 374		break;
 375	case PLATFORM_DEVID_NONE:
 376		dev_set_name(&pdev->dev, "%s", pdev->name);
 377		break;
 378	case PLATFORM_DEVID_AUTO:
 379		/*
 380		 * Automatically allocated device ID. We mark it as such so
 381		 * that we remember it must be freed, and we append a suffix
 382		 * to avoid namespace collision with explicit IDs.
 383		 */
 384		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 385		if (ret < 0)
 386			goto err_out;
 387		pdev->id = ret;
 388		pdev->id_auto = true;
 389		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 390		break;
 391	}
 392
 393	for (i = 0; i < pdev->num_resources; i++) {
 394		struct resource *p, *r = &pdev->resource[i];
 395
 396		if (r->name == NULL)
 397			r->name = dev_name(&pdev->dev);
 398
 399		p = r->parent;
 400		if (!p) {
 401			if (resource_type(r) == IORESOURCE_MEM)
 402				p = &iomem_resource;
 403			else if (resource_type(r) == IORESOURCE_IO)
 404				p = &ioport_resource;
 405		}
 406
 407		if (p && insert_resource(p, r)) {
 408			dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 409			ret = -EBUSY;
 410			goto failed;
 
 
 411		}
 412	}
 413
 414	pr_debug("Registering platform device '%s'. Parent at %s\n",
 415		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 416
 417	ret = device_add(&pdev->dev);
 418	if (ret == 0)
 419		return ret;
 420
 421 failed:
 422	if (pdev->id_auto) {
 423		ida_simple_remove(&platform_devid_ida, pdev->id);
 424		pdev->id = PLATFORM_DEVID_AUTO;
 425	}
 426
 427	while (--i >= 0) {
 428		struct resource *r = &pdev->resource[i];
 429		if (r->parent)
 430			release_resource(r);
 431	}
 432
 433 err_out:
 434	return ret;
 435}
 436EXPORT_SYMBOL_GPL(platform_device_add);
 437
 438/**
 439 * platform_device_del - remove a platform-level device
 440 * @pdev: platform device we're removing
 441 *
 442 * Note that this function will also release all memory- and port-based
 443 * resources owned by the device (@dev->resource).  This function must
 444 * _only_ be externally called in error cases.  All other usage is a bug.
 445 */
 446void platform_device_del(struct platform_device *pdev)
 447{
 448	int i;
 449
 450	if (pdev) {
 451		device_remove_properties(&pdev->dev);
 452		device_del(&pdev->dev);
 453
 454		if (pdev->id_auto) {
 455			ida_simple_remove(&platform_devid_ida, pdev->id);
 456			pdev->id = PLATFORM_DEVID_AUTO;
 457		}
 458
 459		for (i = 0; i < pdev->num_resources; i++) {
 460			struct resource *r = &pdev->resource[i];
 461			if (r->parent)
 462				release_resource(r);
 463		}
 464	}
 465}
 466EXPORT_SYMBOL_GPL(platform_device_del);
 467
 468/**
 469 * platform_device_register - add a platform-level device
 470 * @pdev: platform device we're adding
 
 
 
 
 471 */
 472int platform_device_register(struct platform_device *pdev)
 473{
 474	device_initialize(&pdev->dev);
 475	arch_setup_pdev_archdata(pdev);
 476	return platform_device_add(pdev);
 477}
 478EXPORT_SYMBOL_GPL(platform_device_register);
 479
 480/**
 481 * platform_device_unregister - unregister a platform-level device
 482 * @pdev: platform device we're unregistering
 483 *
 484 * Unregistration is done in 2 steps. First we release all resources
 485 * and remove it from the subsystem, then we drop reference count by
 486 * calling platform_device_put().
 487 */
 488void platform_device_unregister(struct platform_device *pdev)
 489{
 490	platform_device_del(pdev);
 491	platform_device_put(pdev);
 492}
 493EXPORT_SYMBOL_GPL(platform_device_unregister);
 494
 495/**
 496 * platform_device_register_full - add a platform-level device with
 497 * resources and platform-specific data
 498 *
 499 * @pdevinfo: data used to create device
 500 *
 501 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 502 */
 503struct platform_device *platform_device_register_full(
 504		const struct platform_device_info *pdevinfo)
 505{
 506	int ret = -ENOMEM;
 507	struct platform_device *pdev;
 508
 509	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 510	if (!pdev)
 511		goto err_alloc;
 512
 513	pdev->dev.parent = pdevinfo->parent;
 514	pdev->dev.fwnode = pdevinfo->fwnode;
 
 
 515
 516	if (pdevinfo->dma_mask) {
 517		/*
 518		 * This memory isn't freed when the device is put,
 519		 * I don't have a nice idea for that though.  Conceptually
 520		 * dma_mask in struct device should not be a pointer.
 521		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 522		 */
 523		pdev->dev.dma_mask =
 524			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 525		if (!pdev->dev.dma_mask)
 526			goto err;
 527
 528		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 529		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 530	}
 531
 532	ret = platform_device_add_resources(pdev,
 533			pdevinfo->res, pdevinfo->num_res);
 534	if (ret)
 535		goto err;
 536
 537	ret = platform_device_add_data(pdev,
 538			pdevinfo->data, pdevinfo->size_data);
 539	if (ret)
 540		goto err;
 541
 542	if (pdevinfo->properties) {
 543		ret = platform_device_add_properties(pdev,
 544						     pdevinfo->properties);
 545		if (ret)
 546			goto err;
 547	}
 548
 549	ret = platform_device_add(pdev);
 550	if (ret) {
 551err:
 552		ACPI_COMPANION_SET(&pdev->dev, NULL);
 553		kfree(pdev->dev.dma_mask);
 554
 555err_alloc:
 556		platform_device_put(pdev);
 557		return ERR_PTR(ret);
 558	}
 559
 560	return pdev;
 561}
 562EXPORT_SYMBOL_GPL(platform_device_register_full);
 563
 564static int platform_drv_probe(struct device *_dev)
 565{
 566	struct platform_driver *drv = to_platform_driver(_dev->driver);
 567	struct platform_device *dev = to_platform_device(_dev);
 568	int ret;
 569
 570	ret = of_clk_set_defaults(_dev->of_node, false);
 571	if (ret < 0)
 572		return ret;
 573
 574	ret = dev_pm_domain_attach(_dev, true);
 575	if (ret != -EPROBE_DEFER) {
 576		if (drv->probe) {
 577			ret = drv->probe(dev);
 578			if (ret)
 579				dev_pm_domain_detach(_dev, true);
 580		} else {
 581			/* don't fail if just dev_pm_domain_attach failed */
 582			ret = 0;
 583		}
 584	}
 585
 586	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 587		dev_warn(_dev, "probe deferral not supported\n");
 588		ret = -ENXIO;
 589	}
 590
 591	return ret;
 592}
 593
 594static int platform_drv_probe_fail(struct device *_dev)
 595{
 596	return -ENXIO;
 597}
 598
 599static int platform_drv_remove(struct device *_dev)
 600{
 601	struct platform_driver *drv = to_platform_driver(_dev->driver);
 602	struct platform_device *dev = to_platform_device(_dev);
 603	int ret = 0;
 604
 605	if (drv->remove)
 606		ret = drv->remove(dev);
 607	dev_pm_domain_detach(_dev, true);
 608
 609	return ret;
 610}
 611
 612static void platform_drv_shutdown(struct device *_dev)
 613{
 614	struct platform_driver *drv = to_platform_driver(_dev->driver);
 615	struct platform_device *dev = to_platform_device(_dev);
 616
 617	if (drv->shutdown)
 618		drv->shutdown(dev);
 619}
 620
 621/**
 622 * __platform_driver_register - register a driver for platform-level devices
 623 * @drv: platform driver structure
 624 * @owner: owning module/driver
 625 */
 626int __platform_driver_register(struct platform_driver *drv,
 627				struct module *owner)
 628{
 629	drv->driver.owner = owner;
 630	drv->driver.bus = &platform_bus_type;
 631	drv->driver.probe = platform_drv_probe;
 632	drv->driver.remove = platform_drv_remove;
 633	drv->driver.shutdown = platform_drv_shutdown;
 634
 635	return driver_register(&drv->driver);
 636}
 637EXPORT_SYMBOL_GPL(__platform_driver_register);
 638
 639/**
 640 * platform_driver_unregister - unregister a driver for platform-level devices
 641 * @drv: platform driver structure
 642 */
 643void platform_driver_unregister(struct platform_driver *drv)
 644{
 645	driver_unregister(&drv->driver);
 646}
 647EXPORT_SYMBOL_GPL(platform_driver_unregister);
 648
 
 
 
 
 
 649/**
 650 * __platform_driver_probe - register driver for non-hotpluggable device
 651 * @drv: platform driver structure
 652 * @probe: the driver probe routine, probably from an __init section
 653 * @module: module which will be the owner of the driver
 654 *
 655 * Use this instead of platform_driver_register() when you know the device
 656 * is not hotpluggable and has already been registered, and you want to
 657 * remove its run-once probe() infrastructure from memory after the driver
 658 * has bound to the device.
 659 *
 660 * One typical use for this would be with drivers for controllers integrated
 661 * into system-on-chip processors, where the controller devices have been
 662 * configured as part of board setup.
 663 *
 664 * Note that this is incompatible with deferred probing.
 665 *
 666 * Returns zero if the driver registered and bound to a device, else returns
 667 * a negative error code and with the driver not registered.
 668 */
 669int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 670		int (*probe)(struct platform_device *), struct module *module)
 671{
 672	int retval, code;
 673
 674	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 675		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 676			 drv->driver.name, __func__);
 677		return -EINVAL;
 678	}
 679
 680	/*
 681	 * We have to run our probes synchronously because we check if
 682	 * we find any devices to bind to and exit with error if there
 683	 * are any.
 684	 */
 685	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 686
 687	/*
 688	 * Prevent driver from requesting probe deferral to avoid further
 689	 * futile probe attempts.
 690	 */
 691	drv->prevent_deferred_probe = true;
 692
 693	/* make sure driver won't have bind/unbind attributes */
 694	drv->driver.suppress_bind_attrs = true;
 695
 696	/* temporary section violation during probe() */
 697	drv->probe = probe;
 698	retval = code = __platform_driver_register(drv, module);
 
 
 699
 700	/*
 701	 * Fixup that section violation, being paranoid about code scanning
 702	 * the list of drivers in order to probe new devices.  Check to see
 703	 * if the probe was successful, and make sure any forced probes of
 704	 * new devices fail.
 705	 */
 706	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 707	drv->probe = NULL;
 708	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 709		retval = -ENODEV;
 710	drv->driver.probe = platform_drv_probe_fail;
 711	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 712
 713	if (code != retval)
 714		platform_driver_unregister(drv);
 715	return retval;
 716}
 717EXPORT_SYMBOL_GPL(__platform_driver_probe);
 718
 719/**
 720 * __platform_create_bundle - register driver and create corresponding device
 721 * @driver: platform driver structure
 722 * @probe: the driver probe routine, probably from an __init section
 723 * @res: set of resources that needs to be allocated for the device
 724 * @n_res: number of resources
 725 * @data: platform specific data for this platform device
 726 * @size: size of platform specific data
 727 * @module: module which will be the owner of the driver
 728 *
 729 * Use this in legacy-style modules that probe hardware directly and
 730 * register a single platform device and corresponding platform driver.
 731 *
 732 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 733 */
 734struct platform_device * __init_or_module __platform_create_bundle(
 735			struct platform_driver *driver,
 736			int (*probe)(struct platform_device *),
 737			struct resource *res, unsigned int n_res,
 738			const void *data, size_t size, struct module *module)
 739{
 740	struct platform_device *pdev;
 741	int error;
 742
 743	pdev = platform_device_alloc(driver->driver.name, -1);
 744	if (!pdev) {
 745		error = -ENOMEM;
 746		goto err_out;
 747	}
 748
 749	error = platform_device_add_resources(pdev, res, n_res);
 750	if (error)
 751		goto err_pdev_put;
 752
 753	error = platform_device_add_data(pdev, data, size);
 754	if (error)
 755		goto err_pdev_put;
 756
 757	error = platform_device_add(pdev);
 758	if (error)
 759		goto err_pdev_put;
 760
 761	error = __platform_driver_probe(driver, probe, module);
 762	if (error)
 763		goto err_pdev_del;
 764
 765	return pdev;
 766
 767err_pdev_del:
 768	platform_device_del(pdev);
 769err_pdev_put:
 770	platform_device_put(pdev);
 771err_out:
 772	return ERR_PTR(error);
 773}
 774EXPORT_SYMBOL_GPL(__platform_create_bundle);
 775
 776/**
 777 * __platform_register_drivers - register an array of platform drivers
 778 * @drivers: an array of drivers to register
 779 * @count: the number of drivers to register
 780 * @owner: module owning the drivers
 781 *
 782 * Registers platform drivers specified by an array. On failure to register a
 783 * driver, all previously registered drivers will be unregistered. Callers of
 784 * this API should use platform_unregister_drivers() to unregister drivers in
 785 * the reverse order.
 786 *
 787 * Returns: 0 on success or a negative error code on failure.
 788 */
 789int __platform_register_drivers(struct platform_driver * const *drivers,
 790				unsigned int count, struct module *owner)
 791{
 792	unsigned int i;
 793	int err;
 794
 795	for (i = 0; i < count; i++) {
 796		pr_debug("registering platform driver %ps\n", drivers[i]);
 797
 798		err = __platform_driver_register(drivers[i], owner);
 799		if (err < 0) {
 800			pr_err("failed to register platform driver %ps: %d\n",
 801			       drivers[i], err);
 802			goto error;
 803		}
 804	}
 805
 806	return 0;
 807
 808error:
 809	while (i--) {
 810		pr_debug("unregistering platform driver %ps\n", drivers[i]);
 811		platform_driver_unregister(drivers[i]);
 812	}
 813
 814	return err;
 815}
 816EXPORT_SYMBOL_GPL(__platform_register_drivers);
 817
 818/**
 819 * platform_unregister_drivers - unregister an array of platform drivers
 820 * @drivers: an array of drivers to unregister
 821 * @count: the number of drivers to unregister
 822 *
 823 * Unegisters platform drivers specified by an array. This is typically used
 824 * to complement an earlier call to platform_register_drivers(). Drivers are
 825 * unregistered in the reverse order in which they were registered.
 826 */
 827void platform_unregister_drivers(struct platform_driver * const *drivers,
 828				 unsigned int count)
 829{
 830	while (count--) {
 831		pr_debug("unregistering platform driver %ps\n", drivers[count]);
 832		platform_driver_unregister(drivers[count]);
 833	}
 834}
 835EXPORT_SYMBOL_GPL(platform_unregister_drivers);
 836
 837/* modalias support enables more hands-off userspace setup:
 838 * (a) environment variable lets new-style hotplug events work once system is
 839 *     fully running:  "modprobe $MODALIAS"
 840 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 841 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 842 */
 843static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 844			     char *buf)
 845{
 846	struct platform_device	*pdev = to_platform_device(dev);
 847	int len;
 848
 849	len = of_device_modalias(dev, buf, PAGE_SIZE);
 850	if (len != -ENODEV)
 851		return len;
 852
 853	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 854	if (len != -ENODEV)
 855		return len;
 856
 857	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 858
 859	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 860}
 861static DEVICE_ATTR_RO(modalias);
 862
 863static ssize_t driver_override_store(struct device *dev,
 864				     struct device_attribute *attr,
 865				     const char *buf, size_t count)
 866{
 867	struct platform_device *pdev = to_platform_device(dev);
 868	char *driver_override, *old, *cp;
 869
 870	/* We need to keep extra room for a newline */
 871	if (count >= (PAGE_SIZE - 1))
 872		return -EINVAL;
 873
 874	driver_override = kstrndup(buf, count, GFP_KERNEL);
 875	if (!driver_override)
 876		return -ENOMEM;
 877
 878	cp = strchr(driver_override, '\n');
 879	if (cp)
 880		*cp = '\0';
 881
 882	device_lock(dev);
 883	old = pdev->driver_override;
 884	if (strlen(driver_override)) {
 885		pdev->driver_override = driver_override;
 886	} else {
 887		kfree(driver_override);
 888		pdev->driver_override = NULL;
 889	}
 890	device_unlock(dev);
 891
 892	kfree(old);
 893
 894	return count;
 895}
 896
 897static ssize_t driver_override_show(struct device *dev,
 898				    struct device_attribute *attr, char *buf)
 899{
 900	struct platform_device *pdev = to_platform_device(dev);
 901	ssize_t len;
 902
 903	device_lock(dev);
 904	len = sprintf(buf, "%s\n", pdev->driver_override);
 905	device_unlock(dev);
 906	return len;
 907}
 908static DEVICE_ATTR_RW(driver_override);
 909
 910
 911static struct attribute *platform_dev_attrs[] = {
 912	&dev_attr_modalias.attr,
 913	&dev_attr_driver_override.attr,
 914	NULL,
 915};
 916ATTRIBUTE_GROUPS(platform_dev);
 917
 918static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 919{
 920	struct platform_device	*pdev = to_platform_device(dev);
 921	int rc;
 922
 923	/* Some devices have extra OF data and an OF-style MODALIAS */
 924	rc = of_device_uevent_modalias(dev, env);
 925	if (rc != -ENODEV)
 926		return rc;
 927
 928	rc = acpi_device_uevent_modalias(dev, env);
 929	if (rc != -ENODEV)
 930		return rc;
 931
 932	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 933			pdev->name);
 934	return 0;
 935}
 936
 937static const struct platform_device_id *platform_match_id(
 938			const struct platform_device_id *id,
 939			struct platform_device *pdev)
 940{
 941	while (id->name[0]) {
 942		if (strcmp(pdev->name, id->name) == 0) {
 943			pdev->id_entry = id;
 944			return id;
 945		}
 946		id++;
 947	}
 948	return NULL;
 949}
 950
 951/**
 952 * platform_match - bind platform device to platform driver.
 953 * @dev: device.
 954 * @drv: driver.
 955 *
 956 * Platform device IDs are assumed to be encoded like this:
 957 * "<name><instance>", where <name> is a short description of the type of
 958 * device, like "pci" or "floppy", and <instance> is the enumerated
 959 * instance of the device, like '0' or '42'.  Driver IDs are simply
 960 * "<name>".  So, extract the <name> from the platform_device structure,
 961 * and compare it against the name of the driver. Return whether they match
 962 * or not.
 963 */
 964static int platform_match(struct device *dev, struct device_driver *drv)
 965{
 966	struct platform_device *pdev = to_platform_device(dev);
 967	struct platform_driver *pdrv = to_platform_driver(drv);
 968
 969	/* When driver_override is set, only bind to the matching driver */
 970	if (pdev->driver_override)
 971		return !strcmp(pdev->driver_override, drv->name);
 972
 973	/* Attempt an OF style match first */
 974	if (of_driver_match_device(dev, drv))
 975		return 1;
 976
 977	/* Then try ACPI style match */
 978	if (acpi_driver_match_device(dev, drv))
 979		return 1;
 980
 981	/* Then try to match against the id table */
 982	if (pdrv->id_table)
 983		return platform_match_id(pdrv->id_table, pdev) != NULL;
 984
 985	/* fall-back to driver name match */
 986	return (strcmp(pdev->name, drv->name) == 0);
 987}
 988
 989#ifdef CONFIG_PM_SLEEP
 990
 991static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 992{
 993	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 994	struct platform_device *pdev = to_platform_device(dev);
 995	int ret = 0;
 996
 997	if (dev->driver && pdrv->suspend)
 998		ret = pdrv->suspend(pdev, mesg);
 999
1000	return ret;
1001}
1002
1003static int platform_legacy_resume(struct device *dev)
1004{
1005	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1006	struct platform_device *pdev = to_platform_device(dev);
1007	int ret = 0;
1008
1009	if (dev->driver && pdrv->resume)
1010		ret = pdrv->resume(pdev);
1011
1012	return ret;
1013}
1014
1015#endif /* CONFIG_PM_SLEEP */
1016
1017#ifdef CONFIG_SUSPEND
1018
1019int platform_pm_suspend(struct device *dev)
1020{
1021	struct device_driver *drv = dev->driver;
1022	int ret = 0;
1023
1024	if (!drv)
1025		return 0;
1026
1027	if (drv->pm) {
1028		if (drv->pm->suspend)
1029			ret = drv->pm->suspend(dev);
1030	} else {
1031		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1032	}
1033
1034	return ret;
1035}
1036
1037int platform_pm_resume(struct device *dev)
1038{
1039	struct device_driver *drv = dev->driver;
1040	int ret = 0;
1041
1042	if (!drv)
1043		return 0;
1044
1045	if (drv->pm) {
1046		if (drv->pm->resume)
1047			ret = drv->pm->resume(dev);
1048	} else {
1049		ret = platform_legacy_resume(dev);
1050	}
1051
1052	return ret;
1053}
1054
1055#endif /* CONFIG_SUSPEND */
1056
1057#ifdef CONFIG_HIBERNATE_CALLBACKS
1058
1059int platform_pm_freeze(struct device *dev)
1060{
1061	struct device_driver *drv = dev->driver;
1062	int ret = 0;
1063
1064	if (!drv)
1065		return 0;
1066
1067	if (drv->pm) {
1068		if (drv->pm->freeze)
1069			ret = drv->pm->freeze(dev);
1070	} else {
1071		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1072	}
1073
1074	return ret;
1075}
1076
1077int platform_pm_thaw(struct device *dev)
1078{
1079	struct device_driver *drv = dev->driver;
1080	int ret = 0;
1081
1082	if (!drv)
1083		return 0;
1084
1085	if (drv->pm) {
1086		if (drv->pm->thaw)
1087			ret = drv->pm->thaw(dev);
1088	} else {
1089		ret = platform_legacy_resume(dev);
1090	}
1091
1092	return ret;
1093}
1094
1095int platform_pm_poweroff(struct device *dev)
1096{
1097	struct device_driver *drv = dev->driver;
1098	int ret = 0;
1099
1100	if (!drv)
1101		return 0;
1102
1103	if (drv->pm) {
1104		if (drv->pm->poweroff)
1105			ret = drv->pm->poweroff(dev);
1106	} else {
1107		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1108	}
1109
1110	return ret;
1111}
1112
1113int platform_pm_restore(struct device *dev)
1114{
1115	struct device_driver *drv = dev->driver;
1116	int ret = 0;
1117
1118	if (!drv)
1119		return 0;
1120
1121	if (drv->pm) {
1122		if (drv->pm->restore)
1123			ret = drv->pm->restore(dev);
1124	} else {
1125		ret = platform_legacy_resume(dev);
1126	}
1127
1128	return ret;
1129}
1130
1131#endif /* CONFIG_HIBERNATE_CALLBACKS */
1132
1133static const struct dev_pm_ops platform_dev_pm_ops = {
1134	.runtime_suspend = pm_generic_runtime_suspend,
1135	.runtime_resume = pm_generic_runtime_resume,
1136	USE_PLATFORM_PM_SLEEP_OPS
1137};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1138
1139struct bus_type platform_bus_type = {
1140	.name		= "platform",
1141	.dev_groups	= platform_dev_groups,
1142	.match		= platform_match,
1143	.uevent		= platform_uevent,
1144	.pm		= &platform_dev_pm_ops,
1145	.force_dma	= true,
1146};
1147EXPORT_SYMBOL_GPL(platform_bus_type);
1148
1149int __init platform_bus_init(void)
 
 
1150{
1151	int error;
 
1152
1153	early_platform_cleanup();
 
 
1154
1155	error = device_register(&platform_bus);
1156	if (error) {
1157		put_device(&platform_bus);
1158		return error;
1159	}
1160	error =  bus_register(&platform_bus_type);
1161	if (error)
1162		device_unregister(&platform_bus);
1163	of_platform_register_reconfig_notifier();
1164	return error;
1165}
 
 
 
 
 
 
 
 
1166
1167#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1168u64 dma_get_required_mask(struct device *dev)
1169{
1170	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1171	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1172	u64 mask;
1173
1174	if (!high_totalram) {
1175		/* convert to mask just covering totalram */
1176		low_totalram = (1 << (fls(low_totalram) - 1));
1177		low_totalram += low_totalram - 1;
1178		mask = low_totalram;
1179	} else {
1180		high_totalram = (1 << (fls(high_totalram) - 1));
1181		high_totalram += high_totalram - 1;
1182		mask = (((u64)high_totalram) << 32) + 0xffffffff;
1183	}
1184	return mask;
1185}
1186EXPORT_SYMBOL_GPL(dma_get_required_mask);
1187#endif
1188
1189static __initdata LIST_HEAD(early_platform_driver_list);
1190static __initdata LIST_HEAD(early_platform_device_list);
 
 
 
 
1191
1192/**
1193 * early_platform_driver_register - register early platform driver
1194 * @epdrv: early_platform driver structure
1195 * @buf: string passed from early_param()
1196 *
1197 * Helper function for early_platform_init() / early_platform_init_buffer()
 
 
 
 
 
 
1198 */
1199int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1200					  char *buf)
1201{
1202	char *tmp;
1203	int n;
1204
1205	/* Simply add the driver to the end of the global list.
1206	 * Drivers will by default be put on the list in compiled-in order.
1207	 */
1208	if (!epdrv->list.next) {
1209		INIT_LIST_HEAD(&epdrv->list);
1210		list_add_tail(&epdrv->list, &early_platform_driver_list);
1211	}
1212
1213	/* If the user has specified device then make sure the driver
1214	 * gets prioritized. The driver of the last device specified on
1215	 * command line will be put first on the list.
1216	 */
1217	n = strlen(epdrv->pdrv->driver.name);
1218	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1219		list_move(&epdrv->list, &early_platform_driver_list);
1220
1221		/* Allow passing parameters after device name */
1222		if (buf[n] == '\0' || buf[n] == ',')
1223			epdrv->requested_id = -1;
1224		else {
1225			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1226							     &tmp, 10);
1227
1228			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1229				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1230				n = 0;
1231			} else
1232				n += strcspn(&buf[n + 1], ",") + 1;
1233		}
1234
1235		if (buf[n] == ',')
1236			n++;
 
1237
1238		if (epdrv->bufsize) {
1239			memcpy(epdrv->buffer, &buf[n],
1240			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1241			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1242		}
1243	}
1244
1245	return 0;
 
1246}
1247
1248/**
1249 * early_platform_add_devices - adds a number of early platform devices
1250 * @devs: array of early platform devices to add
1251 * @num: number of early platform devices in array
1252 *
1253 * Used by early architecture code to register early platform devices and
1254 * their platform data.
1255 */
1256void __init early_platform_add_devices(struct platform_device **devs, int num)
1257{
1258	struct device *dev;
1259	int i;
 
 
 
 
 
1260
1261	/* simply add the devices to list */
1262	for (i = 0; i < num; i++) {
1263		dev = &devs[i]->dev;
1264
1265		if (!dev->devres_head.next) {
1266			pm_runtime_early_init(dev);
1267			INIT_LIST_HEAD(&dev->devres_head);
1268			list_add_tail(&dev->devres_head,
1269				      &early_platform_device_list);
1270		}
1271	}
1272}
1273
1274/**
1275 * early_platform_driver_register_all - register early platform drivers
1276 * @class_str: string to identify early platform driver class
1277 *
1278 * Used by architecture code to register all early platform drivers
1279 * for a certain class. If omitted then only early platform drivers
1280 * with matching kernel command line class parameters will be registered.
1281 */
1282void __init early_platform_driver_register_all(char *class_str)
1283{
1284	/* The "class_str" parameter may or may not be present on the kernel
1285	 * command line. If it is present then there may be more than one
1286	 * matching parameter.
1287	 *
1288	 * Since we register our early platform drivers using early_param()
1289	 * we need to make sure that they also get registered in the case
1290	 * when the parameter is missing from the kernel command line.
1291	 *
1292	 * We use parse_early_options() to make sure the early_param() gets
1293	 * called at least once. The early_param() may be called more than
1294	 * once since the name of the preferred device may be specified on
1295	 * the kernel command line. early_platform_driver_register() handles
1296	 * this case for us.
1297	 */
1298	parse_early_options(class_str);
1299}
 
 
 
 
 
 
 
 
1300
1301/**
1302 * early_platform_match - find early platform device matching driver
1303 * @epdrv: early platform driver structure
1304 * @id: id to match against
1305 */
1306static struct platform_device * __init
1307early_platform_match(struct early_platform_driver *epdrv, int id)
1308{
1309	struct platform_device *pd;
1310
1311	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1312		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1313			if (pd->id == id)
1314				return pd;
 
1315
1316	return NULL;
1317}
1318
1319/**
1320 * early_platform_left - check if early platform driver has matching devices
1321 * @epdrv: early platform driver structure
1322 * @id: return true if id or above exists
1323 */
1324static int __init early_platform_left(struct early_platform_driver *epdrv,
1325				       int id)
1326{
1327	struct platform_device *pd;
1328
1329	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1330		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1331			if (pd->id >= id)
1332				return 1;
1333
1334	return 0;
 
 
 
1335}
1336
1337/**
1338 * early_platform_driver_probe_id - probe drivers matching class_str and id
1339 * @class_str: string to identify early platform driver class
1340 * @id: id to match against
1341 * @nr_probe: number of platform devices to successfully probe before exiting
1342 */
1343static int __init early_platform_driver_probe_id(char *class_str,
1344						 int id,
1345						 int nr_probe)
1346{
1347	struct early_platform_driver *epdrv;
1348	struct platform_device *match;
1349	int match_id;
1350	int n = 0;
1351	int left = 0;
1352
1353	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1354		/* only use drivers matching our class_str */
1355		if (strcmp(class_str, epdrv->class_str))
1356			continue;
1357
1358		if (id == -2) {
1359			match_id = epdrv->requested_id;
1360			left = 1;
1361
1362		} else {
1363			match_id = id;
1364			left += early_platform_left(epdrv, id);
1365
1366			/* skip requested id */
1367			switch (epdrv->requested_id) {
1368			case EARLY_PLATFORM_ID_ERROR:
1369			case EARLY_PLATFORM_ID_UNSET:
1370				break;
1371			default:
1372				if (epdrv->requested_id == id)
1373					match_id = EARLY_PLATFORM_ID_UNSET;
1374			}
1375		}
1376
1377		switch (match_id) {
1378		case EARLY_PLATFORM_ID_ERROR:
1379			pr_warn("%s: unable to parse %s parameter\n",
1380				class_str, epdrv->pdrv->driver.name);
1381			/* fall-through */
1382		case EARLY_PLATFORM_ID_UNSET:
1383			match = NULL;
1384			break;
1385		default:
1386			match = early_platform_match(epdrv, match_id);
1387		}
1388
1389		if (match) {
1390			/*
1391			 * Set up a sensible init_name to enable
1392			 * dev_name() and others to be used before the
1393			 * rest of the driver core is initialized.
1394			 */
1395			if (!match->dev.init_name && slab_is_available()) {
1396				if (match->id != -1)
1397					match->dev.init_name =
1398						kasprintf(GFP_KERNEL, "%s.%d",
1399							  match->name,
1400							  match->id);
1401				else
1402					match->dev.init_name =
1403						kasprintf(GFP_KERNEL, "%s",
1404							  match->name);
1405
1406				if (!match->dev.init_name)
1407					return -ENOMEM;
1408			}
 
 
 
1409
1410			if (epdrv->pdrv->probe(match))
1411				pr_warn("%s: unable to probe %s early.\n",
1412					class_str, match->name);
1413			else
1414				n++;
1415		}
1416
1417		if (n >= nr_probe)
1418			break;
1419	}
1420
1421	if (left)
1422		return n;
1423	else
1424		return -ENODEV;
1425}
1426
1427/**
1428 * early_platform_driver_probe - probe a class of registered drivers
1429 * @class_str: string to identify early platform driver class
1430 * @nr_probe: number of platform devices to successfully probe before exiting
1431 * @user_only: only probe user specified early platform devices
1432 *
1433 * Used by architecture code to probe registered early platform drivers
1434 * within a certain class. For probe to happen a registered early platform
1435 * device matching a registered early platform driver is needed.
1436 */
1437int __init early_platform_driver_probe(char *class_str,
1438				       int nr_probe,
1439				       int user_only)
1440{
1441	int k, n, i;
1442
1443	n = 0;
1444	for (i = -2; n < nr_probe; i++) {
1445		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1446
1447		if (k < 0)
1448			break;
 
 
1449
1450		n += k;
 
 
 
 
 
 
 
 
 
 
 
 
1451
1452		if (user_only)
1453			break;
1454	}
1455
1456	return n;
1457}
1458
1459/**
1460 * early_platform_cleanup - clean up early platform code
 
 
 
1461 */
1462void __init early_platform_cleanup(void)
 
1463{
1464	struct platform_device *pd, *pd2;
 
 
 
 
 
1465
1466	/* clean up the devres list used to chain devices */
1467	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1468				 dev.devres_head) {
1469		list_del(&pd->dev.devres_head);
1470		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
 
 
 
 
 
1471	}
 
 
 
 
 
1472}
1473