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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
v3.15
   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/idr.h>
  25#include <linux/acpi.h>
 
 
 
  26
  27#include "base.h"
  28#include "power/power.h"
  29
  30/* For automatically allocated device IDs */
  31static DEFINE_IDA(platform_devid_ida);
  32
  33struct device platform_bus = {
  34	.init_name	= "platform",
  35};
  36EXPORT_SYMBOL_GPL(platform_bus);
  37
  38/**
  39 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  40 * @pdev: platform device
  41 *
  42 * This is called before platform_device_add() such that any pdev_archdata may
  43 * be setup before the platform_notifier is called.  So if a user needs to
  44 * manipulate any relevant information in the pdev_archdata they can do:
  45 *
  46 *	platform_device_alloc()
  47 *	... manipulate ...
  48 *	platform_device_add()
  49 *
  50 * And if they don't care they can just call platform_device_register() and
  51 * everything will just work out.
  52 */
  53void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  54{
  55}
  56
  57/**
  58 * platform_get_resource - get a resource for a device
  59 * @dev: platform device
  60 * @type: resource type
  61 * @num: resource index
  62 */
  63struct resource *platform_get_resource(struct platform_device *dev,
  64				       unsigned int type, unsigned int num)
  65{
  66	int i;
  67
  68	for (i = 0; i < dev->num_resources; i++) {
  69		struct resource *r = &dev->resource[i];
  70
  71		if (type == resource_type(r) && num-- == 0)
  72			return r;
  73	}
  74	return NULL;
  75}
  76EXPORT_SYMBOL_GPL(platform_get_resource);
  77
  78/**
  79 * platform_get_irq - get an IRQ for a device
  80 * @dev: platform device
  81 * @num: IRQ number index
  82 */
  83int platform_get_irq(struct platform_device *dev, unsigned int num)
  84{
  85#ifdef CONFIG_SPARC
  86	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
  87	if (!dev || num >= dev->archdata.num_irqs)
  88		return -ENXIO;
  89	return dev->archdata.irqs[num];
  90#else
  91	struct resource *r;
  92	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node)
  93		return of_irq_get(dev->dev.of_node, num);
 
 
 
 
 
  94
  95	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  96
  97	return r ? r->start : -ENXIO;
  98#endif
  99}
 100EXPORT_SYMBOL_GPL(platform_get_irq);
 101
 102/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 103 * platform_get_resource_byname - get a resource for a device by name
 104 * @dev: platform device
 105 * @type: resource type
 106 * @name: resource name
 107 */
 108struct resource *platform_get_resource_byname(struct platform_device *dev,
 109					      unsigned int type,
 110					      const char *name)
 111{
 112	int i;
 113
 114	for (i = 0; i < dev->num_resources; i++) {
 115		struct resource *r = &dev->resource[i];
 116
 117		if (unlikely(!r->name))
 118			continue;
 119
 120		if (type == resource_type(r) && !strcmp(r->name, name))
 121			return r;
 122	}
 123	return NULL;
 124}
 125EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 126
 127/**
 128 * platform_get_irq_byname - get an IRQ for a device by name
 129 * @dev: platform device
 130 * @name: IRQ name
 131 */
 132int platform_get_irq_byname(struct platform_device *dev, const char *name)
 133{
 134	struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
 135							  name);
 136
 
 
 
 
 
 
 
 
 
 137	return r ? r->start : -ENXIO;
 138}
 139EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 140
 141/**
 142 * platform_add_devices - add a numbers of platform devices
 143 * @devs: array of platform devices to add
 144 * @num: number of platform devices in array
 145 */
 146int platform_add_devices(struct platform_device **devs, int num)
 147{
 148	int i, ret = 0;
 149
 150	for (i = 0; i < num; i++) {
 151		ret = platform_device_register(devs[i]);
 152		if (ret) {
 153			while (--i >= 0)
 154				platform_device_unregister(devs[i]);
 155			break;
 156		}
 157	}
 158
 159	return ret;
 160}
 161EXPORT_SYMBOL_GPL(platform_add_devices);
 162
 163struct platform_object {
 164	struct platform_device pdev;
 165	char name[1];
 166};
 167
 168/**
 169 * platform_device_put - destroy a platform device
 170 * @pdev: platform device to free
 171 *
 172 * Free all memory associated with a platform device.  This function must
 173 * _only_ be externally called in error cases.  All other usage is a bug.
 174 */
 175void platform_device_put(struct platform_device *pdev)
 176{
 177	if (pdev)
 178		put_device(&pdev->dev);
 179}
 180EXPORT_SYMBOL_GPL(platform_device_put);
 181
 182static void platform_device_release(struct device *dev)
 183{
 184	struct platform_object *pa = container_of(dev, struct platform_object,
 185						  pdev.dev);
 186
 187	of_device_node_put(&pa->pdev.dev);
 188	kfree(pa->pdev.dev.platform_data);
 189	kfree(pa->pdev.mfd_cell);
 190	kfree(pa->pdev.resource);
 
 191	kfree(pa);
 192}
 193
 194/**
 195 * platform_device_alloc - create a platform device
 196 * @name: base name of the device we're adding
 197 * @id: instance id
 198 *
 199 * Create a platform device object which can have other objects attached
 200 * to it, and which will have attached objects freed when it is released.
 201 */
 202struct platform_device *platform_device_alloc(const char *name, int id)
 203{
 204	struct platform_object *pa;
 205
 206	pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
 207	if (pa) {
 208		strcpy(pa->name, name);
 209		pa->pdev.name = pa->name;
 210		pa->pdev.id = id;
 211		device_initialize(&pa->pdev.dev);
 212		pa->pdev.dev.release = platform_device_release;
 213		arch_setup_pdev_archdata(&pa->pdev);
 214	}
 215
 216	return pa ? &pa->pdev : NULL;
 217}
 218EXPORT_SYMBOL_GPL(platform_device_alloc);
 219
 220/**
 221 * platform_device_add_resources - add resources to a platform device
 222 * @pdev: platform device allocated by platform_device_alloc to add resources to
 223 * @res: set of resources that needs to be allocated for the device
 224 * @num: number of resources
 225 *
 226 * Add a copy of the resources to the platform device.  The memory
 227 * associated with the resources will be freed when the platform device is
 228 * released.
 229 */
 230int platform_device_add_resources(struct platform_device *pdev,
 231				  const struct resource *res, unsigned int num)
 232{
 233	struct resource *r = NULL;
 234
 235	if (res) {
 236		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 237		if (!r)
 238			return -ENOMEM;
 239	}
 240
 241	kfree(pdev->resource);
 242	pdev->resource = r;
 243	pdev->num_resources = num;
 244	return 0;
 245}
 246EXPORT_SYMBOL_GPL(platform_device_add_resources);
 247
 248/**
 249 * platform_device_add_data - add platform-specific data to a platform device
 250 * @pdev: platform device allocated by platform_device_alloc to add resources to
 251 * @data: platform specific data for this platform device
 252 * @size: size of platform specific data
 253 *
 254 * Add a copy of platform specific data to the platform device's
 255 * platform_data pointer.  The memory associated with the platform data
 256 * will be freed when the platform device is released.
 257 */
 258int platform_device_add_data(struct platform_device *pdev, const void *data,
 259			     size_t size)
 260{
 261	void *d = NULL;
 262
 263	if (data) {
 264		d = kmemdup(data, size, GFP_KERNEL);
 265		if (!d)
 266			return -ENOMEM;
 267	}
 268
 269	kfree(pdev->dev.platform_data);
 270	pdev->dev.platform_data = d;
 271	return 0;
 272}
 273EXPORT_SYMBOL_GPL(platform_device_add_data);
 274
 275/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 276 * platform_device_add - add a platform device to device hierarchy
 277 * @pdev: platform device we're adding
 278 *
 279 * This is part 2 of platform_device_register(), though may be called
 280 * separately _iff_ pdev was allocated by platform_device_alloc().
 281 */
 282int platform_device_add(struct platform_device *pdev)
 283{
 284	int i, ret;
 285
 286	if (!pdev)
 287		return -EINVAL;
 288
 289	if (!pdev->dev.parent)
 290		pdev->dev.parent = &platform_bus;
 291
 292	pdev->dev.bus = &platform_bus_type;
 293
 294	switch (pdev->id) {
 295	default:
 296		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 297		break;
 298	case PLATFORM_DEVID_NONE:
 299		dev_set_name(&pdev->dev, "%s", pdev->name);
 300		break;
 301	case PLATFORM_DEVID_AUTO:
 302		/*
 303		 * Automatically allocated device ID. We mark it as such so
 304		 * that we remember it must be freed, and we append a suffix
 305		 * to avoid namespace collision with explicit IDs.
 306		 */
 307		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 308		if (ret < 0)
 309			goto err_out;
 310		pdev->id = ret;
 311		pdev->id_auto = true;
 312		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 313		break;
 314	}
 315
 316	for (i = 0; i < pdev->num_resources; i++) {
 317		struct resource *p, *r = &pdev->resource[i];
 318
 319		if (r->name == NULL)
 320			r->name = dev_name(&pdev->dev);
 321
 322		p = r->parent;
 323		if (!p) {
 324			if (resource_type(r) == IORESOURCE_MEM)
 325				p = &iomem_resource;
 326			else if (resource_type(r) == IORESOURCE_IO)
 327				p = &ioport_resource;
 328		}
 329
 330		if (p && insert_resource(p, r)) {
 331			dev_err(&pdev->dev, "failed to claim resource %d\n", i);
 332			ret = -EBUSY;
 333			goto failed;
 334		}
 335	}
 336
 337	pr_debug("Registering platform device '%s'. Parent at %s\n",
 338		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 339
 340	ret = device_add(&pdev->dev);
 341	if (ret == 0)
 342		return ret;
 343
 344 failed:
 345	if (pdev->id_auto) {
 346		ida_simple_remove(&platform_devid_ida, pdev->id);
 347		pdev->id = PLATFORM_DEVID_AUTO;
 348	}
 349
 350	while (--i >= 0) {
 351		struct resource *r = &pdev->resource[i];
 352		unsigned long type = resource_type(r);
 353
 354		if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 355			release_resource(r);
 356	}
 357
 358 err_out:
 359	return ret;
 360}
 361EXPORT_SYMBOL_GPL(platform_device_add);
 362
 363/**
 364 * platform_device_del - remove a platform-level device
 365 * @pdev: platform device we're removing
 366 *
 367 * Note that this function will also release all memory- and port-based
 368 * resources owned by the device (@dev->resource).  This function must
 369 * _only_ be externally called in error cases.  All other usage is a bug.
 370 */
 371void platform_device_del(struct platform_device *pdev)
 372{
 373	int i;
 374
 375	if (pdev) {
 
 376		device_del(&pdev->dev);
 377
 378		if (pdev->id_auto) {
 379			ida_simple_remove(&platform_devid_ida, pdev->id);
 380			pdev->id = PLATFORM_DEVID_AUTO;
 381		}
 382
 383		for (i = 0; i < pdev->num_resources; i++) {
 384			struct resource *r = &pdev->resource[i];
 385			unsigned long type = resource_type(r);
 386
 387			if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 388				release_resource(r);
 389		}
 390	}
 391}
 392EXPORT_SYMBOL_GPL(platform_device_del);
 393
 394/**
 395 * platform_device_register - add a platform-level device
 396 * @pdev: platform device we're adding
 397 */
 398int platform_device_register(struct platform_device *pdev)
 399{
 400	device_initialize(&pdev->dev);
 401	arch_setup_pdev_archdata(pdev);
 402	return platform_device_add(pdev);
 403}
 404EXPORT_SYMBOL_GPL(platform_device_register);
 405
 406/**
 407 * platform_device_unregister - unregister a platform-level device
 408 * @pdev: platform device we're unregistering
 409 *
 410 * Unregistration is done in 2 steps. First we release all resources
 411 * and remove it from the subsystem, then we drop reference count by
 412 * calling platform_device_put().
 413 */
 414void platform_device_unregister(struct platform_device *pdev)
 415{
 416	platform_device_del(pdev);
 417	platform_device_put(pdev);
 418}
 419EXPORT_SYMBOL_GPL(platform_device_unregister);
 420
 421/**
 422 * platform_device_register_full - add a platform-level device with
 423 * resources and platform-specific data
 424 *
 425 * @pdevinfo: data used to create device
 426 *
 427 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 428 */
 429struct platform_device *platform_device_register_full(
 430		const struct platform_device_info *pdevinfo)
 431{
 432	int ret = -ENOMEM;
 433	struct platform_device *pdev;
 434
 435	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 436	if (!pdev)
 437		goto err_alloc;
 438
 439	pdev->dev.parent = pdevinfo->parent;
 440	ACPI_COMPANION_SET(&pdev->dev, pdevinfo->acpi_node.companion);
 441
 442	if (pdevinfo->dma_mask) {
 443		/*
 444		 * This memory isn't freed when the device is put,
 445		 * I don't have a nice idea for that though.  Conceptually
 446		 * dma_mask in struct device should not be a pointer.
 447		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 448		 */
 449		pdev->dev.dma_mask =
 450			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 451		if (!pdev->dev.dma_mask)
 452			goto err;
 453
 454		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 455		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 456	}
 457
 458	ret = platform_device_add_resources(pdev,
 459			pdevinfo->res, pdevinfo->num_res);
 460	if (ret)
 461		goto err;
 462
 463	ret = platform_device_add_data(pdev,
 464			pdevinfo->data, pdevinfo->size_data);
 465	if (ret)
 466		goto err;
 467
 
 
 
 
 
 
 
 468	ret = platform_device_add(pdev);
 469	if (ret) {
 470err:
 471		ACPI_COMPANION_SET(&pdev->dev, NULL);
 472		kfree(pdev->dev.dma_mask);
 473
 474err_alloc:
 475		platform_device_put(pdev);
 476		return ERR_PTR(ret);
 477	}
 478
 479	return pdev;
 480}
 481EXPORT_SYMBOL_GPL(platform_device_register_full);
 482
 483static int platform_drv_probe(struct device *_dev)
 484{
 485	struct platform_driver *drv = to_platform_driver(_dev->driver);
 486	struct platform_device *dev = to_platform_device(_dev);
 487	int ret;
 488
 489	acpi_dev_pm_attach(_dev, true);
 
 
 490
 491	ret = drv->probe(dev);
 492	if (ret)
 493		acpi_dev_pm_detach(_dev, true);
 
 
 
 
 
 
 
 
 494
 495	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 496		dev_warn(_dev, "probe deferral not supported\n");
 497		ret = -ENXIO;
 498	}
 499
 500	return ret;
 501}
 502
 503static int platform_drv_probe_fail(struct device *_dev)
 504{
 505	return -ENXIO;
 506}
 507
 508static int platform_drv_remove(struct device *_dev)
 509{
 510	struct platform_driver *drv = to_platform_driver(_dev->driver);
 511	struct platform_device *dev = to_platform_device(_dev);
 512	int ret;
 513
 514	ret = drv->remove(dev);
 515	acpi_dev_pm_detach(_dev, true);
 
 516
 517	return ret;
 518}
 519
 520static void platform_drv_shutdown(struct device *_dev)
 521{
 522	struct platform_driver *drv = to_platform_driver(_dev->driver);
 523	struct platform_device *dev = to_platform_device(_dev);
 524
 525	drv->shutdown(dev);
 526	acpi_dev_pm_detach(_dev, true);
 527}
 528
 529/**
 530 * __platform_driver_register - register a driver for platform-level devices
 531 * @drv: platform driver structure
 532 * @owner: owning module/driver
 533 */
 534int __platform_driver_register(struct platform_driver *drv,
 535				struct module *owner)
 536{
 537	drv->driver.owner = owner;
 538	drv->driver.bus = &platform_bus_type;
 539	if (drv->probe)
 540		drv->driver.probe = platform_drv_probe;
 541	if (drv->remove)
 542		drv->driver.remove = platform_drv_remove;
 543	if (drv->shutdown)
 544		drv->driver.shutdown = platform_drv_shutdown;
 545
 546	return driver_register(&drv->driver);
 547}
 548EXPORT_SYMBOL_GPL(__platform_driver_register);
 549
 550/**
 551 * platform_driver_unregister - unregister a driver for platform-level devices
 552 * @drv: platform driver structure
 553 */
 554void platform_driver_unregister(struct platform_driver *drv)
 555{
 556	driver_unregister(&drv->driver);
 557}
 558EXPORT_SYMBOL_GPL(platform_driver_unregister);
 559
 560/**
 561 * platform_driver_probe - register driver for non-hotpluggable device
 562 * @drv: platform driver structure
 563 * @probe: the driver probe routine, probably from an __init section
 
 564 *
 565 * Use this instead of platform_driver_register() when you know the device
 566 * is not hotpluggable and has already been registered, and you want to
 567 * remove its run-once probe() infrastructure from memory after the driver
 568 * has bound to the device.
 569 *
 570 * One typical use for this would be with drivers for controllers integrated
 571 * into system-on-chip processors, where the controller devices have been
 572 * configured as part of board setup.
 573 *
 574 * Note that this is incompatible with deferred probing.
 575 *
 576 * Returns zero if the driver registered and bound to a device, else returns
 577 * a negative error code and with the driver not registered.
 578 */
 579int __init_or_module platform_driver_probe(struct platform_driver *drv,
 580		int (*probe)(struct platform_device *))
 581{
 582	int retval, code;
 583
 
 
 
 
 
 
 
 
 
 
 
 
 
 584	/*
 585	 * Prevent driver from requesting probe deferral to avoid further
 586	 * futile probe attempts.
 587	 */
 588	drv->prevent_deferred_probe = true;
 589
 590	/* make sure driver won't have bind/unbind attributes */
 591	drv->driver.suppress_bind_attrs = true;
 592
 593	/* temporary section violation during probe() */
 594	drv->probe = probe;
 595	retval = code = platform_driver_register(drv);
 596
 597	/*
 598	 * Fixup that section violation, being paranoid about code scanning
 599	 * the list of drivers in order to probe new devices.  Check to see
 600	 * if the probe was successful, and make sure any forced probes of
 601	 * new devices fail.
 602	 */
 603	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 604	drv->probe = NULL;
 605	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 606		retval = -ENODEV;
 607	drv->driver.probe = platform_drv_probe_fail;
 608	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 609
 610	if (code != retval)
 611		platform_driver_unregister(drv);
 612	return retval;
 613}
 614EXPORT_SYMBOL_GPL(platform_driver_probe);
 615
 616/**
 617 * platform_create_bundle - register driver and create corresponding device
 618 * @driver: platform driver structure
 619 * @probe: the driver probe routine, probably from an __init section
 620 * @res: set of resources that needs to be allocated for the device
 621 * @n_res: number of resources
 622 * @data: platform specific data for this platform device
 623 * @size: size of platform specific data
 
 624 *
 625 * Use this in legacy-style modules that probe hardware directly and
 626 * register a single platform device and corresponding platform driver.
 627 *
 628 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 629 */
 630struct platform_device * __init_or_module platform_create_bundle(
 631			struct platform_driver *driver,
 632			int (*probe)(struct platform_device *),
 633			struct resource *res, unsigned int n_res,
 634			const void *data, size_t size)
 635{
 636	struct platform_device *pdev;
 637	int error;
 638
 639	pdev = platform_device_alloc(driver->driver.name, -1);
 640	if (!pdev) {
 641		error = -ENOMEM;
 642		goto err_out;
 643	}
 644
 645	error = platform_device_add_resources(pdev, res, n_res);
 646	if (error)
 647		goto err_pdev_put;
 648
 649	error = platform_device_add_data(pdev, data, size);
 650	if (error)
 651		goto err_pdev_put;
 652
 653	error = platform_device_add(pdev);
 654	if (error)
 655		goto err_pdev_put;
 656
 657	error = platform_driver_probe(driver, probe);
 658	if (error)
 659		goto err_pdev_del;
 660
 661	return pdev;
 662
 663err_pdev_del:
 664	platform_device_del(pdev);
 665err_pdev_put:
 666	platform_device_put(pdev);
 667err_out:
 668	return ERR_PTR(error);
 669}
 670EXPORT_SYMBOL_GPL(platform_create_bundle);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 671
 672/* modalias support enables more hands-off userspace setup:
 673 * (a) environment variable lets new-style hotplug events work once system is
 674 *     fully running:  "modprobe $MODALIAS"
 675 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 676 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 677 */
 678static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 679			     char *buf)
 680{
 681	struct platform_device	*pdev = to_platform_device(dev);
 682	int len;
 683
 684	len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
 685	if (len != -ENODEV)
 686		return len;
 687
 688	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 689	if (len != -ENODEV)
 690		return len;
 691
 692	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 693
 694	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 695}
 696static DEVICE_ATTR_RO(modalias);
 697
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 698static struct attribute *platform_dev_attrs[] = {
 699	&dev_attr_modalias.attr,
 
 700	NULL,
 701};
 702ATTRIBUTE_GROUPS(platform_dev);
 703
 704static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 705{
 706	struct platform_device	*pdev = to_platform_device(dev);
 707	int rc;
 708
 709	/* Some devices have extra OF data and an OF-style MODALIAS */
 710	rc = of_device_uevent_modalias(dev, env);
 711	if (rc != -ENODEV)
 712		return rc;
 713
 714	rc = acpi_device_uevent_modalias(dev, env);
 715	if (rc != -ENODEV)
 716		return rc;
 717
 718	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 719			pdev->name);
 720	return 0;
 721}
 722
 723static const struct platform_device_id *platform_match_id(
 724			const struct platform_device_id *id,
 725			struct platform_device *pdev)
 726{
 727	while (id->name[0]) {
 728		if (strcmp(pdev->name, id->name) == 0) {
 729			pdev->id_entry = id;
 730			return id;
 731		}
 732		id++;
 733	}
 734	return NULL;
 735}
 736
 737/**
 738 * platform_match - bind platform device to platform driver.
 739 * @dev: device.
 740 * @drv: driver.
 741 *
 742 * Platform device IDs are assumed to be encoded like this:
 743 * "<name><instance>", where <name> is a short description of the type of
 744 * device, like "pci" or "floppy", and <instance> is the enumerated
 745 * instance of the device, like '0' or '42'.  Driver IDs are simply
 746 * "<name>".  So, extract the <name> from the platform_device structure,
 747 * and compare it against the name of the driver. Return whether they match
 748 * or not.
 749 */
 750static int platform_match(struct device *dev, struct device_driver *drv)
 751{
 752	struct platform_device *pdev = to_platform_device(dev);
 753	struct platform_driver *pdrv = to_platform_driver(drv);
 754
 
 
 
 
 755	/* Attempt an OF style match first */
 756	if (of_driver_match_device(dev, drv))
 757		return 1;
 758
 759	/* Then try ACPI style match */
 760	if (acpi_driver_match_device(dev, drv))
 761		return 1;
 762
 763	/* Then try to match against the id table */
 764	if (pdrv->id_table)
 765		return platform_match_id(pdrv->id_table, pdev) != NULL;
 766
 767	/* fall-back to driver name match */
 768	return (strcmp(pdev->name, drv->name) == 0);
 769}
 770
 771#ifdef CONFIG_PM_SLEEP
 772
 773static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 774{
 775	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 776	struct platform_device *pdev = to_platform_device(dev);
 777	int ret = 0;
 778
 779	if (dev->driver && pdrv->suspend)
 780		ret = pdrv->suspend(pdev, mesg);
 781
 782	return ret;
 783}
 784
 785static int platform_legacy_resume(struct device *dev)
 786{
 787	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 788	struct platform_device *pdev = to_platform_device(dev);
 789	int ret = 0;
 790
 791	if (dev->driver && pdrv->resume)
 792		ret = pdrv->resume(pdev);
 793
 794	return ret;
 795}
 796
 797#endif /* CONFIG_PM_SLEEP */
 798
 799#ifdef CONFIG_SUSPEND
 800
 801int platform_pm_suspend(struct device *dev)
 802{
 803	struct device_driver *drv = dev->driver;
 804	int ret = 0;
 805
 806	if (!drv)
 807		return 0;
 808
 809	if (drv->pm) {
 810		if (drv->pm->suspend)
 811			ret = drv->pm->suspend(dev);
 812	} else {
 813		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
 814	}
 815
 816	return ret;
 817}
 818
 819int platform_pm_resume(struct device *dev)
 820{
 821	struct device_driver *drv = dev->driver;
 822	int ret = 0;
 823
 824	if (!drv)
 825		return 0;
 826
 827	if (drv->pm) {
 828		if (drv->pm->resume)
 829			ret = drv->pm->resume(dev);
 830	} else {
 831		ret = platform_legacy_resume(dev);
 832	}
 833
 834	return ret;
 835}
 836
 837#endif /* CONFIG_SUSPEND */
 838
 839#ifdef CONFIG_HIBERNATE_CALLBACKS
 840
 841int platform_pm_freeze(struct device *dev)
 842{
 843	struct device_driver *drv = dev->driver;
 844	int ret = 0;
 845
 846	if (!drv)
 847		return 0;
 848
 849	if (drv->pm) {
 850		if (drv->pm->freeze)
 851			ret = drv->pm->freeze(dev);
 852	} else {
 853		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
 854	}
 855
 856	return ret;
 857}
 858
 859int platform_pm_thaw(struct device *dev)
 860{
 861	struct device_driver *drv = dev->driver;
 862	int ret = 0;
 863
 864	if (!drv)
 865		return 0;
 866
 867	if (drv->pm) {
 868		if (drv->pm->thaw)
 869			ret = drv->pm->thaw(dev);
 870	} else {
 871		ret = platform_legacy_resume(dev);
 872	}
 873
 874	return ret;
 875}
 876
 877int platform_pm_poweroff(struct device *dev)
 878{
 879	struct device_driver *drv = dev->driver;
 880	int ret = 0;
 881
 882	if (!drv)
 883		return 0;
 884
 885	if (drv->pm) {
 886		if (drv->pm->poweroff)
 887			ret = drv->pm->poweroff(dev);
 888	} else {
 889		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
 890	}
 891
 892	return ret;
 893}
 894
 895int platform_pm_restore(struct device *dev)
 896{
 897	struct device_driver *drv = dev->driver;
 898	int ret = 0;
 899
 900	if (!drv)
 901		return 0;
 902
 903	if (drv->pm) {
 904		if (drv->pm->restore)
 905			ret = drv->pm->restore(dev);
 906	} else {
 907		ret = platform_legacy_resume(dev);
 908	}
 909
 910	return ret;
 911}
 912
 913#endif /* CONFIG_HIBERNATE_CALLBACKS */
 914
 915static const struct dev_pm_ops platform_dev_pm_ops = {
 916	.runtime_suspend = pm_generic_runtime_suspend,
 917	.runtime_resume = pm_generic_runtime_resume,
 918	USE_PLATFORM_PM_SLEEP_OPS
 919};
 920
 921struct bus_type platform_bus_type = {
 922	.name		= "platform",
 923	.dev_groups	= platform_dev_groups,
 924	.match		= platform_match,
 925	.uevent		= platform_uevent,
 926	.pm		= &platform_dev_pm_ops,
 927};
 928EXPORT_SYMBOL_GPL(platform_bus_type);
 929
 930int __init platform_bus_init(void)
 931{
 932	int error;
 933
 934	early_platform_cleanup();
 935
 936	error = device_register(&platform_bus);
 937	if (error)
 938		return error;
 939	error =  bus_register(&platform_bus_type);
 940	if (error)
 941		device_unregister(&platform_bus);
 
 942	return error;
 943}
 944
 945#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
 946u64 dma_get_required_mask(struct device *dev)
 947{
 948	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
 949	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
 950	u64 mask;
 951
 952	if (!high_totalram) {
 953		/* convert to mask just covering totalram */
 954		low_totalram = (1 << (fls(low_totalram) - 1));
 955		low_totalram += low_totalram - 1;
 956		mask = low_totalram;
 957	} else {
 958		high_totalram = (1 << (fls(high_totalram) - 1));
 959		high_totalram += high_totalram - 1;
 960		mask = (((u64)high_totalram) << 32) + 0xffffffff;
 961	}
 962	return mask;
 963}
 964EXPORT_SYMBOL_GPL(dma_get_required_mask);
 965#endif
 966
 967static __initdata LIST_HEAD(early_platform_driver_list);
 968static __initdata LIST_HEAD(early_platform_device_list);
 969
 970/**
 971 * early_platform_driver_register - register early platform driver
 972 * @epdrv: early_platform driver structure
 973 * @buf: string passed from early_param()
 974 *
 975 * Helper function for early_platform_init() / early_platform_init_buffer()
 976 */
 977int __init early_platform_driver_register(struct early_platform_driver *epdrv,
 978					  char *buf)
 979{
 980	char *tmp;
 981	int n;
 982
 983	/* Simply add the driver to the end of the global list.
 984	 * Drivers will by default be put on the list in compiled-in order.
 985	 */
 986	if (!epdrv->list.next) {
 987		INIT_LIST_HEAD(&epdrv->list);
 988		list_add_tail(&epdrv->list, &early_platform_driver_list);
 989	}
 990
 991	/* If the user has specified device then make sure the driver
 992	 * gets prioritized. The driver of the last device specified on
 993	 * command line will be put first on the list.
 994	 */
 995	n = strlen(epdrv->pdrv->driver.name);
 996	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
 997		list_move(&epdrv->list, &early_platform_driver_list);
 998
 999		/* Allow passing parameters after device name */
1000		if (buf[n] == '\0' || buf[n] == ',')
1001			epdrv->requested_id = -1;
1002		else {
1003			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1004							     &tmp, 10);
1005
1006			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1007				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1008				n = 0;
1009			} else
1010				n += strcspn(&buf[n + 1], ",") + 1;
1011		}
1012
1013		if (buf[n] == ',')
1014			n++;
1015
1016		if (epdrv->bufsize) {
1017			memcpy(epdrv->buffer, &buf[n],
1018			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1019			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1020		}
1021	}
1022
1023	return 0;
1024}
1025
1026/**
1027 * early_platform_add_devices - adds a number of early platform devices
1028 * @devs: array of early platform devices to add
1029 * @num: number of early platform devices in array
1030 *
1031 * Used by early architecture code to register early platform devices and
1032 * their platform data.
1033 */
1034void __init early_platform_add_devices(struct platform_device **devs, int num)
1035{
1036	struct device *dev;
1037	int i;
1038
1039	/* simply add the devices to list */
1040	for (i = 0; i < num; i++) {
1041		dev = &devs[i]->dev;
1042
1043		if (!dev->devres_head.next) {
1044			pm_runtime_early_init(dev);
1045			INIT_LIST_HEAD(&dev->devres_head);
1046			list_add_tail(&dev->devres_head,
1047				      &early_platform_device_list);
1048		}
1049	}
1050}
1051
1052/**
1053 * early_platform_driver_register_all - register early platform drivers
1054 * @class_str: string to identify early platform driver class
1055 *
1056 * Used by architecture code to register all early platform drivers
1057 * for a certain class. If omitted then only early platform drivers
1058 * with matching kernel command line class parameters will be registered.
1059 */
1060void __init early_platform_driver_register_all(char *class_str)
1061{
1062	/* The "class_str" parameter may or may not be present on the kernel
1063	 * command line. If it is present then there may be more than one
1064	 * matching parameter.
1065	 *
1066	 * Since we register our early platform drivers using early_param()
1067	 * we need to make sure that they also get registered in the case
1068	 * when the parameter is missing from the kernel command line.
1069	 *
1070	 * We use parse_early_options() to make sure the early_param() gets
1071	 * called at least once. The early_param() may be called more than
1072	 * once since the name of the preferred device may be specified on
1073	 * the kernel command line. early_platform_driver_register() handles
1074	 * this case for us.
1075	 */
1076	parse_early_options(class_str);
1077}
1078
1079/**
1080 * early_platform_match - find early platform device matching driver
1081 * @epdrv: early platform driver structure
1082 * @id: id to match against
1083 */
1084static struct platform_device * __init
1085early_platform_match(struct early_platform_driver *epdrv, int id)
1086{
1087	struct platform_device *pd;
1088
1089	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1090		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1091			if (pd->id == id)
1092				return pd;
1093
1094	return NULL;
1095}
1096
1097/**
1098 * early_platform_left - check if early platform driver has matching devices
1099 * @epdrv: early platform driver structure
1100 * @id: return true if id or above exists
1101 */
1102static int __init early_platform_left(struct early_platform_driver *epdrv,
1103				       int id)
1104{
1105	struct platform_device *pd;
1106
1107	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1108		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1109			if (pd->id >= id)
1110				return 1;
1111
1112	return 0;
1113}
1114
1115/**
1116 * early_platform_driver_probe_id - probe drivers matching class_str and id
1117 * @class_str: string to identify early platform driver class
1118 * @id: id to match against
1119 * @nr_probe: number of platform devices to successfully probe before exiting
1120 */
1121static int __init early_platform_driver_probe_id(char *class_str,
1122						 int id,
1123						 int nr_probe)
1124{
1125	struct early_platform_driver *epdrv;
1126	struct platform_device *match;
1127	int match_id;
1128	int n = 0;
1129	int left = 0;
1130
1131	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1132		/* only use drivers matching our class_str */
1133		if (strcmp(class_str, epdrv->class_str))
1134			continue;
1135
1136		if (id == -2) {
1137			match_id = epdrv->requested_id;
1138			left = 1;
1139
1140		} else {
1141			match_id = id;
1142			left += early_platform_left(epdrv, id);
1143
1144			/* skip requested id */
1145			switch (epdrv->requested_id) {
1146			case EARLY_PLATFORM_ID_ERROR:
1147			case EARLY_PLATFORM_ID_UNSET:
1148				break;
1149			default:
1150				if (epdrv->requested_id == id)
1151					match_id = EARLY_PLATFORM_ID_UNSET;
1152			}
1153		}
1154
1155		switch (match_id) {
1156		case EARLY_PLATFORM_ID_ERROR:
1157			pr_warn("%s: unable to parse %s parameter\n",
1158				class_str, epdrv->pdrv->driver.name);
1159			/* fall-through */
1160		case EARLY_PLATFORM_ID_UNSET:
1161			match = NULL;
1162			break;
1163		default:
1164			match = early_platform_match(epdrv, match_id);
1165		}
1166
1167		if (match) {
1168			/*
1169			 * Set up a sensible init_name to enable
1170			 * dev_name() and others to be used before the
1171			 * rest of the driver core is initialized.
1172			 */
1173			if (!match->dev.init_name && slab_is_available()) {
1174				if (match->id != -1)
1175					match->dev.init_name =
1176						kasprintf(GFP_KERNEL, "%s.%d",
1177							  match->name,
1178							  match->id);
1179				else
1180					match->dev.init_name =
1181						kasprintf(GFP_KERNEL, "%s",
1182							  match->name);
1183
1184				if (!match->dev.init_name)
1185					return -ENOMEM;
1186			}
1187
1188			if (epdrv->pdrv->probe(match))
1189				pr_warn("%s: unable to probe %s early.\n",
1190					class_str, match->name);
1191			else
1192				n++;
1193		}
1194
1195		if (n >= nr_probe)
1196			break;
1197	}
1198
1199	if (left)
1200		return n;
1201	else
1202		return -ENODEV;
1203}
1204
1205/**
1206 * early_platform_driver_probe - probe a class of registered drivers
1207 * @class_str: string to identify early platform driver class
1208 * @nr_probe: number of platform devices to successfully probe before exiting
1209 * @user_only: only probe user specified early platform devices
1210 *
1211 * Used by architecture code to probe registered early platform drivers
1212 * within a certain class. For probe to happen a registered early platform
1213 * device matching a registered early platform driver is needed.
1214 */
1215int __init early_platform_driver_probe(char *class_str,
1216				       int nr_probe,
1217				       int user_only)
1218{
1219	int k, n, i;
1220
1221	n = 0;
1222	for (i = -2; n < nr_probe; i++) {
1223		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1224
1225		if (k < 0)
1226			break;
1227
1228		n += k;
1229
1230		if (user_only)
1231			break;
1232	}
1233
1234	return n;
1235}
1236
1237/**
1238 * early_platform_cleanup - clean up early platform code
1239 */
1240void __init early_platform_cleanup(void)
1241{
1242	struct platform_device *pd, *pd2;
1243
1244	/* clean up the devres list used to chain devices */
1245	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1246				 dev.devres_head) {
1247		list_del(&pd->dev.devres_head);
1248		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1249	}
1250}
1251