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v3.1
   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/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
  24#include "base.h"
 
  25
  26#define to_platform_driver(drv)	(container_of((drv), struct platform_driver, \
  27				 driver))
  28
  29struct device platform_bus = {
  30	.init_name	= "platform",
  31};
  32EXPORT_SYMBOL_GPL(platform_bus);
  33
  34/**
  35 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  36 * @pdev: platform device
  37 *
  38 * This is called before platform_device_add() such that any pdev_archdata may
  39 * be setup before the platform_notifier is called.  So if a user needs to
  40 * manipulate any relevant information in the pdev_archdata they can do:
  41 *
  42 * 	platform_devic_alloc()
  43 * 	... manipulate ...
  44 * 	platform_device_add()
  45 *
  46 * And if they don't care they can just call platform_device_register() and
  47 * everything will just work out.
  48 */
  49void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  50{
  51}
  52
  53/**
  54 * platform_get_resource - get a resource for a device
  55 * @dev: platform device
  56 * @type: resource type
  57 * @num: resource index
  58 */
  59struct resource *platform_get_resource(struct platform_device *dev,
  60				       unsigned int type, unsigned int num)
  61{
  62	int i;
  63
  64	for (i = 0; i < dev->num_resources; i++) {
  65		struct resource *r = &dev->resource[i];
  66
  67		if (type == resource_type(r) && num-- == 0)
  68			return r;
  69	}
  70	return NULL;
  71}
  72EXPORT_SYMBOL_GPL(platform_get_resource);
  73
  74/**
  75 * platform_get_irq - get an IRQ for a device
  76 * @dev: platform device
  77 * @num: IRQ number index
  78 */
  79int platform_get_irq(struct platform_device *dev, unsigned int num)
  80{
  81	struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 
 
 
 
 
 
 
 
 
 
  82
  83	return r ? r->start : -ENXIO;
 
  84}
  85EXPORT_SYMBOL_GPL(platform_get_irq);
  86
  87/**
  88 * platform_get_resource_byname - get a resource for a device by name
  89 * @dev: platform device
  90 * @type: resource type
  91 * @name: resource name
  92 */
  93struct resource *platform_get_resource_byname(struct platform_device *dev,
  94					      unsigned int type,
  95					      const char *name)
  96{
  97	int i;
  98
  99	for (i = 0; i < dev->num_resources; i++) {
 100		struct resource *r = &dev->resource[i];
 101
 
 
 
 102		if (type == resource_type(r) && !strcmp(r->name, name))
 103			return r;
 104	}
 105	return NULL;
 106}
 107EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 108
 109/**
 110 * platform_get_irq - get an IRQ for a device
 111 * @dev: platform device
 112 * @name: IRQ name
 113 */
 114int platform_get_irq_byname(struct platform_device *dev, const char *name)
 115{
 116	struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
 117							  name);
 118
 119	return r ? r->start : -ENXIO;
 120}
 121EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 122
 123/**
 124 * platform_add_devices - add a numbers of platform devices
 125 * @devs: array of platform devices to add
 126 * @num: number of platform devices in array
 127 */
 128int platform_add_devices(struct platform_device **devs, int num)
 129{
 130	int i, ret = 0;
 131
 132	for (i = 0; i < num; i++) {
 133		ret = platform_device_register(devs[i]);
 134		if (ret) {
 135			while (--i >= 0)
 136				platform_device_unregister(devs[i]);
 137			break;
 138		}
 139	}
 140
 141	return ret;
 142}
 143EXPORT_SYMBOL_GPL(platform_add_devices);
 144
 145struct platform_object {
 146	struct platform_device pdev;
 147	char name[1];
 148};
 149
 150/**
 151 * platform_device_put - destroy a platform device
 152 * @pdev: platform device to free
 153 *
 154 * Free all memory associated with a platform device.  This function must
 155 * _only_ be externally called in error cases.  All other usage is a bug.
 156 */
 157void platform_device_put(struct platform_device *pdev)
 158{
 159	if (pdev)
 160		put_device(&pdev->dev);
 161}
 162EXPORT_SYMBOL_GPL(platform_device_put);
 163
 164static void platform_device_release(struct device *dev)
 165{
 166	struct platform_object *pa = container_of(dev, struct platform_object,
 167						  pdev.dev);
 168
 169	of_device_node_put(&pa->pdev.dev);
 170	kfree(pa->pdev.dev.platform_data);
 171	kfree(pa->pdev.mfd_cell);
 172	kfree(pa->pdev.resource);
 173	kfree(pa);
 174}
 175
 176/**
 177 * platform_device_alloc - create a platform device
 178 * @name: base name of the device we're adding
 179 * @id: instance id
 180 *
 181 * Create a platform device object which can have other objects attached
 182 * to it, and which will have attached objects freed when it is released.
 183 */
 184struct platform_device *platform_device_alloc(const char *name, int id)
 185{
 186	struct platform_object *pa;
 187
 188	pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
 189	if (pa) {
 190		strcpy(pa->name, name);
 191		pa->pdev.name = pa->name;
 192		pa->pdev.id = id;
 193		device_initialize(&pa->pdev.dev);
 194		pa->pdev.dev.release = platform_device_release;
 195		arch_setup_pdev_archdata(&pa->pdev);
 196	}
 197
 198	return pa ? &pa->pdev : NULL;
 199}
 200EXPORT_SYMBOL_GPL(platform_device_alloc);
 201
 202/**
 203 * platform_device_add_resources - add resources to a platform device
 204 * @pdev: platform device allocated by platform_device_alloc to add resources to
 205 * @res: set of resources that needs to be allocated for the device
 206 * @num: number of resources
 207 *
 208 * Add a copy of the resources to the platform device.  The memory
 209 * associated with the resources will be freed when the platform device is
 210 * released.
 211 */
 212int platform_device_add_resources(struct platform_device *pdev,
 213				  const struct resource *res, unsigned int num)
 214{
 215	struct resource *r = NULL;
 216
 217	if (res) {
 218		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 219		if (!r)
 220			return -ENOMEM;
 221	}
 222
 223	kfree(pdev->resource);
 224	pdev->resource = r;
 225	pdev->num_resources = num;
 226	return 0;
 227}
 228EXPORT_SYMBOL_GPL(platform_device_add_resources);
 229
 230/**
 231 * platform_device_add_data - add platform-specific data to a platform device
 232 * @pdev: platform device allocated by platform_device_alloc to add resources to
 233 * @data: platform specific data for this platform device
 234 * @size: size of platform specific data
 235 *
 236 * Add a copy of platform specific data to the platform device's
 237 * platform_data pointer.  The memory associated with the platform data
 238 * will be freed when the platform device is released.
 239 */
 240int platform_device_add_data(struct platform_device *pdev, const void *data,
 241			     size_t size)
 242{
 243	void *d = NULL;
 244
 245	if (data) {
 246		d = kmemdup(data, size, GFP_KERNEL);
 247		if (!d)
 248			return -ENOMEM;
 249	}
 250
 251	kfree(pdev->dev.platform_data);
 252	pdev->dev.platform_data = d;
 253	return 0;
 254}
 255EXPORT_SYMBOL_GPL(platform_device_add_data);
 256
 257/**
 258 * platform_device_add - add a platform device to device hierarchy
 259 * @pdev: platform device we're adding
 260 *
 261 * This is part 2 of platform_device_register(), though may be called
 262 * separately _iff_ pdev was allocated by platform_device_alloc().
 263 */
 264int platform_device_add(struct platform_device *pdev)
 265{
 266	int i, ret = 0;
 267
 268	if (!pdev)
 269		return -EINVAL;
 270
 271	if (!pdev->dev.parent)
 272		pdev->dev.parent = &platform_bus;
 273
 274	pdev->dev.bus = &platform_bus_type;
 275
 276	if (pdev->id != -1)
 
 277		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 278	else
 
 279		dev_set_name(&pdev->dev, "%s", pdev->name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 280
 281	for (i = 0; i < pdev->num_resources; i++) {
 282		struct resource *p, *r = &pdev->resource[i];
 283
 284		if (r->name == NULL)
 285			r->name = dev_name(&pdev->dev);
 286
 287		p = r->parent;
 288		if (!p) {
 289			if (resource_type(r) == IORESOURCE_MEM)
 290				p = &iomem_resource;
 291			else if (resource_type(r) == IORESOURCE_IO)
 292				p = &ioport_resource;
 293		}
 294
 295		if (p && insert_resource(p, r)) {
 296			printk(KERN_ERR
 297			       "%s: failed to claim resource %d\n",
 298			       dev_name(&pdev->dev), i);
 299			ret = -EBUSY;
 300			goto failed;
 301		}
 302	}
 303
 304	pr_debug("Registering platform device '%s'. Parent at %s\n",
 305		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 306
 307	ret = device_add(&pdev->dev);
 308	if (ret == 0)
 309		return ret;
 310
 311 failed:
 
 
 
 
 
 312	while (--i >= 0) {
 313		struct resource *r = &pdev->resource[i];
 314		unsigned long type = resource_type(r);
 315
 316		if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 317			release_resource(r);
 318	}
 319
 
 320	return ret;
 321}
 322EXPORT_SYMBOL_GPL(platform_device_add);
 323
 324/**
 325 * platform_device_del - remove a platform-level device
 326 * @pdev: platform device we're removing
 327 *
 328 * Note that this function will also release all memory- and port-based
 329 * resources owned by the device (@dev->resource).  This function must
 330 * _only_ be externally called in error cases.  All other usage is a bug.
 331 */
 332void platform_device_del(struct platform_device *pdev)
 333{
 334	int i;
 335
 336	if (pdev) {
 337		device_del(&pdev->dev);
 338
 
 
 
 
 
 339		for (i = 0; i < pdev->num_resources; i++) {
 340			struct resource *r = &pdev->resource[i];
 341			unsigned long type = resource_type(r);
 342
 343			if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
 344				release_resource(r);
 345		}
 346	}
 347}
 348EXPORT_SYMBOL_GPL(platform_device_del);
 349
 350/**
 351 * platform_device_register - add a platform-level device
 352 * @pdev: platform device we're adding
 353 */
 354int platform_device_register(struct platform_device *pdev)
 355{
 356	device_initialize(&pdev->dev);
 357	arch_setup_pdev_archdata(pdev);
 358	return platform_device_add(pdev);
 359}
 360EXPORT_SYMBOL_GPL(platform_device_register);
 361
 362/**
 363 * platform_device_unregister - unregister a platform-level device
 364 * @pdev: platform device we're unregistering
 365 *
 366 * Unregistration is done in 2 steps. First we release all resources
 367 * and remove it from the subsystem, then we drop reference count by
 368 * calling platform_device_put().
 369 */
 370void platform_device_unregister(struct platform_device *pdev)
 371{
 372	platform_device_del(pdev);
 373	platform_device_put(pdev);
 374}
 375EXPORT_SYMBOL_GPL(platform_device_unregister);
 376
 377/**
 378 * platform_device_register_resndata - add a platform-level device with
 379 * resources and platform-specific data
 380 *
 381 * @parent: parent device for the device we're adding
 382 * @name: base name of the device we're adding
 383 * @id: instance id
 384 * @res: set of resources that needs to be allocated for the device
 385 * @num: number of resources
 386 * @data: platform specific data for this platform device
 387 * @size: size of platform specific data
 388 *
 389 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 390 */
 391struct platform_device *platform_device_register_resndata(
 392		struct device *parent,
 393		const char *name, int id,
 394		const struct resource *res, unsigned int num,
 395		const void *data, size_t size)
 396{
 397	int ret = -ENOMEM;
 398	struct platform_device *pdev;
 399
 400	pdev = platform_device_alloc(name, id);
 401	if (!pdev)
 402		goto err;
 
 
 
 403
 404	pdev->dev.parent = parent;
 
 
 
 
 
 
 
 
 
 
 405
 406	ret = platform_device_add_resources(pdev, res, num);
 
 
 
 
 
 407	if (ret)
 408		goto err;
 409
 410	ret = platform_device_add_data(pdev, data, size);
 
 411	if (ret)
 412		goto err;
 413
 414	ret = platform_device_add(pdev);
 415	if (ret) {
 416err:
 
 
 
 
 417		platform_device_put(pdev);
 418		return ERR_PTR(ret);
 419	}
 420
 421	return pdev;
 422}
 423EXPORT_SYMBOL_GPL(platform_device_register_resndata);
 424
 425static int platform_drv_probe(struct device *_dev)
 426{
 427	struct platform_driver *drv = to_platform_driver(_dev->driver);
 428	struct platform_device *dev = to_platform_device(_dev);
 
 429
 430	return drv->probe(dev);
 
 
 
 
 
 
 
 
 
 
 
 431}
 432
 433static int platform_drv_probe_fail(struct device *_dev)
 434{
 435	return -ENXIO;
 436}
 437
 438static int platform_drv_remove(struct device *_dev)
 439{
 440	struct platform_driver *drv = to_platform_driver(_dev->driver);
 441	struct platform_device *dev = to_platform_device(_dev);
 
 442
 443	return drv->remove(dev);
 
 
 
 444}
 445
 446static void platform_drv_shutdown(struct device *_dev)
 447{
 448	struct platform_driver *drv = to_platform_driver(_dev->driver);
 449	struct platform_device *dev = to_platform_device(_dev);
 450
 451	drv->shutdown(dev);
 
 452}
 453
 454/**
 455 * platform_driver_register - register a driver for platform-level devices
 456 * @drv: platform driver structure
 
 457 */
 458int platform_driver_register(struct platform_driver *drv)
 
 459{
 
 460	drv->driver.bus = &platform_bus_type;
 461	if (drv->probe)
 462		drv->driver.probe = platform_drv_probe;
 463	if (drv->remove)
 464		drv->driver.remove = platform_drv_remove;
 465	if (drv->shutdown)
 466		drv->driver.shutdown = platform_drv_shutdown;
 467
 468	return driver_register(&drv->driver);
 469}
 470EXPORT_SYMBOL_GPL(platform_driver_register);
 471
 472/**
 473 * platform_driver_unregister - unregister a driver for platform-level devices
 474 * @drv: platform driver structure
 475 */
 476void platform_driver_unregister(struct platform_driver *drv)
 477{
 478	driver_unregister(&drv->driver);
 479}
 480EXPORT_SYMBOL_GPL(platform_driver_unregister);
 481
 482/**
 483 * platform_driver_probe - register driver for non-hotpluggable device
 484 * @drv: platform driver structure
 485 * @probe: the driver probe routine, probably from an __init section
 486 *
 487 * Use this instead of platform_driver_register() when you know the device
 488 * is not hotpluggable and has already been registered, and you want to
 489 * remove its run-once probe() infrastructure from memory after the driver
 490 * has bound to the device.
 491 *
 492 * One typical use for this would be with drivers for controllers integrated
 493 * into system-on-chip processors, where the controller devices have been
 494 * configured as part of board setup.
 495 *
 
 
 496 * Returns zero if the driver registered and bound to a device, else returns
 497 * a negative error code and with the driver not registered.
 498 */
 499int __init_or_module platform_driver_probe(struct platform_driver *drv,
 500		int (*probe)(struct platform_device *))
 501{
 502	int retval, code;
 503
 
 
 
 
 
 
 504	/* make sure driver won't have bind/unbind attributes */
 505	drv->driver.suppress_bind_attrs = true;
 506
 507	/* temporary section violation during probe() */
 508	drv->probe = probe;
 509	retval = code = platform_driver_register(drv);
 510
 511	/*
 512	 * Fixup that section violation, being paranoid about code scanning
 513	 * the list of drivers in order to probe new devices.  Check to see
 514	 * if the probe was successful, and make sure any forced probes of
 515	 * new devices fail.
 516	 */
 517	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 518	drv->probe = NULL;
 519	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 520		retval = -ENODEV;
 521	drv->driver.probe = platform_drv_probe_fail;
 522	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 523
 524	if (code != retval)
 525		platform_driver_unregister(drv);
 526	return retval;
 527}
 528EXPORT_SYMBOL_GPL(platform_driver_probe);
 529
 530/**
 531 * platform_create_bundle - register driver and create corresponding device
 532 * @driver: platform driver structure
 533 * @probe: the driver probe routine, probably from an __init section
 534 * @res: set of resources that needs to be allocated for the device
 535 * @n_res: number of resources
 536 * @data: platform specific data for this platform device
 537 * @size: size of platform specific data
 538 *
 539 * Use this in legacy-style modules that probe hardware directly and
 540 * register a single platform device and corresponding platform driver.
 541 *
 542 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 543 */
 544struct platform_device * __init_or_module platform_create_bundle(
 545			struct platform_driver *driver,
 546			int (*probe)(struct platform_device *),
 547			struct resource *res, unsigned int n_res,
 548			const void *data, size_t size)
 549{
 550	struct platform_device *pdev;
 551	int error;
 552
 553	pdev = platform_device_alloc(driver->driver.name, -1);
 554	if (!pdev) {
 555		error = -ENOMEM;
 556		goto err_out;
 557	}
 558
 559	error = platform_device_add_resources(pdev, res, n_res);
 560	if (error)
 561		goto err_pdev_put;
 562
 563	error = platform_device_add_data(pdev, data, size);
 564	if (error)
 565		goto err_pdev_put;
 566
 567	error = platform_device_add(pdev);
 568	if (error)
 569		goto err_pdev_put;
 570
 571	error = platform_driver_probe(driver, probe);
 572	if (error)
 573		goto err_pdev_del;
 574
 575	return pdev;
 576
 577err_pdev_del:
 578	platform_device_del(pdev);
 579err_pdev_put:
 580	platform_device_put(pdev);
 581err_out:
 582	return ERR_PTR(error);
 583}
 584EXPORT_SYMBOL_GPL(platform_create_bundle);
 585
 586/* modalias support enables more hands-off userspace setup:
 587 * (a) environment variable lets new-style hotplug events work once system is
 588 *     fully running:  "modprobe $MODALIAS"
 589 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 590 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 591 */
 592static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 593			     char *buf)
 594{
 595	struct platform_device	*pdev = to_platform_device(dev);
 596	int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 
 
 
 
 
 
 
 
 
 
 597
 598	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 599}
 
 600
 601static struct device_attribute platform_dev_attrs[] = {
 602	__ATTR_RO(modalias),
 603	__ATTR_NULL,
 604};
 
 605
 606static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 607{
 608	struct platform_device	*pdev = to_platform_device(dev);
 609	int rc;
 610
 611	/* Some devices have extra OF data and an OF-style MODALIAS */
 612	rc = of_device_uevent(dev,env);
 
 
 
 
 613	if (rc != -ENODEV)
 614		return rc;
 615
 616	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 617		(pdev->id_entry) ? pdev->id_entry->name : pdev->name);
 618	return 0;
 619}
 620
 621static const struct platform_device_id *platform_match_id(
 622			const struct platform_device_id *id,
 623			struct platform_device *pdev)
 624{
 625	while (id->name[0]) {
 626		if (strcmp(pdev->name, id->name) == 0) {
 627			pdev->id_entry = id;
 628			return id;
 629		}
 630		id++;
 631	}
 632	return NULL;
 633}
 634
 635/**
 636 * platform_match - bind platform device to platform driver.
 637 * @dev: device.
 638 * @drv: driver.
 639 *
 640 * Platform device IDs are assumed to be encoded like this:
 641 * "<name><instance>", where <name> is a short description of the type of
 642 * device, like "pci" or "floppy", and <instance> is the enumerated
 643 * instance of the device, like '0' or '42'.  Driver IDs are simply
 644 * "<name>".  So, extract the <name> from the platform_device structure,
 645 * and compare it against the name of the driver. Return whether they match
 646 * or not.
 647 */
 648static int platform_match(struct device *dev, struct device_driver *drv)
 649{
 650	struct platform_device *pdev = to_platform_device(dev);
 651	struct platform_driver *pdrv = to_platform_driver(drv);
 652
 653	/* Attempt an OF style match first */
 654	if (of_driver_match_device(dev, drv))
 655		return 1;
 656
 
 
 
 
 657	/* Then try to match against the id table */
 658	if (pdrv->id_table)
 659		return platform_match_id(pdrv->id_table, pdev) != NULL;
 660
 661	/* fall-back to driver name match */
 662	return (strcmp(pdev->name, drv->name) == 0);
 663}
 664
 665#ifdef CONFIG_PM_SLEEP
 666
 667static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 668{
 669	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 670	struct platform_device *pdev = to_platform_device(dev);
 671	int ret = 0;
 672
 673	if (dev->driver && pdrv->suspend)
 674		ret = pdrv->suspend(pdev, mesg);
 675
 676	return ret;
 677}
 678
 679static int platform_legacy_resume(struct device *dev)
 680{
 681	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 682	struct platform_device *pdev = to_platform_device(dev);
 683	int ret = 0;
 684
 685	if (dev->driver && pdrv->resume)
 686		ret = pdrv->resume(pdev);
 687
 688	return ret;
 689}
 690
 691int platform_pm_prepare(struct device *dev)
 692{
 693	struct device_driver *drv = dev->driver;
 694	int ret = 0;
 695
 696	if (drv && drv->pm && drv->pm->prepare)
 697		ret = drv->pm->prepare(dev);
 698
 699	return ret;
 700}
 701
 702void platform_pm_complete(struct device *dev)
 703{
 704	struct device_driver *drv = dev->driver;
 705
 706	if (drv && drv->pm && drv->pm->complete)
 707		drv->pm->complete(dev);
 708}
 709
 710#endif /* CONFIG_PM_SLEEP */
 711
 712#ifdef CONFIG_SUSPEND
 713
 714int platform_pm_suspend(struct device *dev)
 715{
 716	struct device_driver *drv = dev->driver;
 717	int ret = 0;
 718
 719	if (!drv)
 720		return 0;
 721
 722	if (drv->pm) {
 723		if (drv->pm->suspend)
 724			ret = drv->pm->suspend(dev);
 725	} else {
 726		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
 727	}
 728
 729	return ret;
 730}
 731
 732int platform_pm_suspend_noirq(struct device *dev)
 733{
 734	struct device_driver *drv = dev->driver;
 735	int ret = 0;
 736
 737	if (!drv)
 738		return 0;
 739
 740	if (drv->pm) {
 741		if (drv->pm->suspend_noirq)
 742			ret = drv->pm->suspend_noirq(dev);
 743	}
 744
 745	return ret;
 746}
 747
 748int platform_pm_resume(struct device *dev)
 749{
 750	struct device_driver *drv = dev->driver;
 751	int ret = 0;
 752
 753	if (!drv)
 754		return 0;
 755
 756	if (drv->pm) {
 757		if (drv->pm->resume)
 758			ret = drv->pm->resume(dev);
 759	} else {
 760		ret = platform_legacy_resume(dev);
 761	}
 762
 763	return ret;
 764}
 765
 766int platform_pm_resume_noirq(struct device *dev)
 767{
 768	struct device_driver *drv = dev->driver;
 769	int ret = 0;
 770
 771	if (!drv)
 772		return 0;
 773
 774	if (drv->pm) {
 775		if (drv->pm->resume_noirq)
 776			ret = drv->pm->resume_noirq(dev);
 777	}
 778
 779	return ret;
 780}
 781
 782#endif /* CONFIG_SUSPEND */
 783
 784#ifdef CONFIG_HIBERNATE_CALLBACKS
 785
 786int platform_pm_freeze(struct device *dev)
 787{
 788	struct device_driver *drv = dev->driver;
 789	int ret = 0;
 790
 791	if (!drv)
 792		return 0;
 793
 794	if (drv->pm) {
 795		if (drv->pm->freeze)
 796			ret = drv->pm->freeze(dev);
 797	} else {
 798		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
 799	}
 800
 801	return ret;
 802}
 803
 804int platform_pm_freeze_noirq(struct device *dev)
 805{
 806	struct device_driver *drv = dev->driver;
 807	int ret = 0;
 808
 809	if (!drv)
 810		return 0;
 811
 812	if (drv->pm) {
 813		if (drv->pm->freeze_noirq)
 814			ret = drv->pm->freeze_noirq(dev);
 815	}
 816
 817	return ret;
 818}
 819
 820int platform_pm_thaw(struct device *dev)
 821{
 822	struct device_driver *drv = dev->driver;
 823	int ret = 0;
 824
 825	if (!drv)
 826		return 0;
 827
 828	if (drv->pm) {
 829		if (drv->pm->thaw)
 830			ret = drv->pm->thaw(dev);
 831	} else {
 832		ret = platform_legacy_resume(dev);
 833	}
 834
 835	return ret;
 836}
 837
 838int platform_pm_thaw_noirq(struct device *dev)
 839{
 840	struct device_driver *drv = dev->driver;
 841	int ret = 0;
 842
 843	if (!drv)
 844		return 0;
 845
 846	if (drv->pm) {
 847		if (drv->pm->thaw_noirq)
 848			ret = drv->pm->thaw_noirq(dev);
 849	}
 850
 851	return ret;
 852}
 853
 854int platform_pm_poweroff(struct device *dev)
 855{
 856	struct device_driver *drv = dev->driver;
 857	int ret = 0;
 858
 859	if (!drv)
 860		return 0;
 861
 862	if (drv->pm) {
 863		if (drv->pm->poweroff)
 864			ret = drv->pm->poweroff(dev);
 865	} else {
 866		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
 867	}
 868
 869	return ret;
 870}
 871
 872int platform_pm_poweroff_noirq(struct device *dev)
 873{
 874	struct device_driver *drv = dev->driver;
 875	int ret = 0;
 876
 877	if (!drv)
 878		return 0;
 879
 880	if (drv->pm) {
 881		if (drv->pm->poweroff_noirq)
 882			ret = drv->pm->poweroff_noirq(dev);
 883	}
 884
 885	return ret;
 886}
 887
 888int platform_pm_restore(struct device *dev)
 889{
 890	struct device_driver *drv = dev->driver;
 891	int ret = 0;
 892
 893	if (!drv)
 894		return 0;
 895
 896	if (drv->pm) {
 897		if (drv->pm->restore)
 898			ret = drv->pm->restore(dev);
 899	} else {
 900		ret = platform_legacy_resume(dev);
 901	}
 902
 903	return ret;
 904}
 905
 906int platform_pm_restore_noirq(struct device *dev)
 907{
 908	struct device_driver *drv = dev->driver;
 909	int ret = 0;
 910
 911	if (!drv)
 912		return 0;
 913
 914	if (drv->pm) {
 915		if (drv->pm->restore_noirq)
 916			ret = drv->pm->restore_noirq(dev);
 917	}
 918
 919	return ret;
 920}
 921
 922#endif /* CONFIG_HIBERNATE_CALLBACKS */
 923
 924static const struct dev_pm_ops platform_dev_pm_ops = {
 925	.runtime_suspend = pm_generic_runtime_suspend,
 926	.runtime_resume = pm_generic_runtime_resume,
 927	.runtime_idle = pm_generic_runtime_idle,
 928	USE_PLATFORM_PM_SLEEP_OPS
 929};
 930
 931struct bus_type platform_bus_type = {
 932	.name		= "platform",
 933	.dev_attrs	= platform_dev_attrs,
 934	.match		= platform_match,
 935	.uevent		= platform_uevent,
 936	.pm		= &platform_dev_pm_ops,
 937};
 938EXPORT_SYMBOL_GPL(platform_bus_type);
 939
 940int __init platform_bus_init(void)
 941{
 942	int error;
 943
 944	early_platform_cleanup();
 945
 946	error = device_register(&platform_bus);
 947	if (error)
 948		return error;
 949	error =  bus_register(&platform_bus_type);
 950	if (error)
 951		device_unregister(&platform_bus);
 952	return error;
 953}
 954
 955#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
 956u64 dma_get_required_mask(struct device *dev)
 957{
 958	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
 959	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
 960	u64 mask;
 961
 962	if (!high_totalram) {
 963		/* convert to mask just covering totalram */
 964		low_totalram = (1 << (fls(low_totalram) - 1));
 965		low_totalram += low_totalram - 1;
 966		mask = low_totalram;
 967	} else {
 968		high_totalram = (1 << (fls(high_totalram) - 1));
 969		high_totalram += high_totalram - 1;
 970		mask = (((u64)high_totalram) << 32) + 0xffffffff;
 971	}
 972	return mask;
 973}
 974EXPORT_SYMBOL_GPL(dma_get_required_mask);
 975#endif
 976
 977static __initdata LIST_HEAD(early_platform_driver_list);
 978static __initdata LIST_HEAD(early_platform_device_list);
 979
 980/**
 981 * early_platform_driver_register - register early platform driver
 982 * @epdrv: early_platform driver structure
 983 * @buf: string passed from early_param()
 984 *
 985 * Helper function for early_platform_init() / early_platform_init_buffer()
 986 */
 987int __init early_platform_driver_register(struct early_platform_driver *epdrv,
 988					  char *buf)
 989{
 990	char *tmp;
 991	int n;
 992
 993	/* Simply add the driver to the end of the global list.
 994	 * Drivers will by default be put on the list in compiled-in order.
 995	 */
 996	if (!epdrv->list.next) {
 997		INIT_LIST_HEAD(&epdrv->list);
 998		list_add_tail(&epdrv->list, &early_platform_driver_list);
 999	}
1000
1001	/* If the user has specified device then make sure the driver
1002	 * gets prioritized. The driver of the last device specified on
1003	 * command line will be put first on the list.
1004	 */
1005	n = strlen(epdrv->pdrv->driver.name);
1006	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1007		list_move(&epdrv->list, &early_platform_driver_list);
1008
1009		/* Allow passing parameters after device name */
1010		if (buf[n] == '\0' || buf[n] == ',')
1011			epdrv->requested_id = -1;
1012		else {
1013			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1014							     &tmp, 10);
1015
1016			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1017				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1018				n = 0;
1019			} else
1020				n += strcspn(&buf[n + 1], ",") + 1;
1021		}
1022
1023		if (buf[n] == ',')
1024			n++;
1025
1026		if (epdrv->bufsize) {
1027			memcpy(epdrv->buffer, &buf[n],
1028			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1029			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1030		}
1031	}
1032
1033	return 0;
1034}
1035
1036/**
1037 * early_platform_add_devices - adds a number of early platform devices
1038 * @devs: array of early platform devices to add
1039 * @num: number of early platform devices in array
1040 *
1041 * Used by early architecture code to register early platform devices and
1042 * their platform data.
1043 */
1044void __init early_platform_add_devices(struct platform_device **devs, int num)
1045{
1046	struct device *dev;
1047	int i;
1048
1049	/* simply add the devices to list */
1050	for (i = 0; i < num; i++) {
1051		dev = &devs[i]->dev;
1052
1053		if (!dev->devres_head.next) {
 
1054			INIT_LIST_HEAD(&dev->devres_head);
1055			list_add_tail(&dev->devres_head,
1056				      &early_platform_device_list);
1057		}
1058	}
1059}
1060
1061/**
1062 * early_platform_driver_register_all - register early platform drivers
1063 * @class_str: string to identify early platform driver class
1064 *
1065 * Used by architecture code to register all early platform drivers
1066 * for a certain class. If omitted then only early platform drivers
1067 * with matching kernel command line class parameters will be registered.
1068 */
1069void __init early_platform_driver_register_all(char *class_str)
1070{
1071	/* The "class_str" parameter may or may not be present on the kernel
1072	 * command line. If it is present then there may be more than one
1073	 * matching parameter.
1074	 *
1075	 * Since we register our early platform drivers using early_param()
1076	 * we need to make sure that they also get registered in the case
1077	 * when the parameter is missing from the kernel command line.
1078	 *
1079	 * We use parse_early_options() to make sure the early_param() gets
1080	 * called at least once. The early_param() may be called more than
1081	 * once since the name of the preferred device may be specified on
1082	 * the kernel command line. early_platform_driver_register() handles
1083	 * this case for us.
1084	 */
1085	parse_early_options(class_str);
1086}
1087
1088/**
1089 * early_platform_match - find early platform device matching driver
1090 * @epdrv: early platform driver structure
1091 * @id: id to match against
1092 */
1093static  __init struct platform_device *
1094early_platform_match(struct early_platform_driver *epdrv, int id)
1095{
1096	struct platform_device *pd;
1097
1098	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1099		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1100			if (pd->id == id)
1101				return pd;
1102
1103	return NULL;
1104}
1105
1106/**
1107 * early_platform_left - check if early platform driver has matching devices
1108 * @epdrv: early platform driver structure
1109 * @id: return true if id or above exists
1110 */
1111static  __init int early_platform_left(struct early_platform_driver *epdrv,
1112				       int id)
1113{
1114	struct platform_device *pd;
1115
1116	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1117		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1118			if (pd->id >= id)
1119				return 1;
1120
1121	return 0;
1122}
1123
1124/**
1125 * early_platform_driver_probe_id - probe drivers matching class_str and id
1126 * @class_str: string to identify early platform driver class
1127 * @id: id to match against
1128 * @nr_probe: number of platform devices to successfully probe before exiting
1129 */
1130static int __init early_platform_driver_probe_id(char *class_str,
1131						 int id,
1132						 int nr_probe)
1133{
1134	struct early_platform_driver *epdrv;
1135	struct platform_device *match;
1136	int match_id;
1137	int n = 0;
1138	int left = 0;
1139
1140	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1141		/* only use drivers matching our class_str */
1142		if (strcmp(class_str, epdrv->class_str))
1143			continue;
1144
1145		if (id == -2) {
1146			match_id = epdrv->requested_id;
1147			left = 1;
1148
1149		} else {
1150			match_id = id;
1151			left += early_platform_left(epdrv, id);
1152
1153			/* skip requested id */
1154			switch (epdrv->requested_id) {
1155			case EARLY_PLATFORM_ID_ERROR:
1156			case EARLY_PLATFORM_ID_UNSET:
1157				break;
1158			default:
1159				if (epdrv->requested_id == id)
1160					match_id = EARLY_PLATFORM_ID_UNSET;
1161			}
1162		}
1163
1164		switch (match_id) {
1165		case EARLY_PLATFORM_ID_ERROR:
1166			pr_warning("%s: unable to parse %s parameter\n",
1167				   class_str, epdrv->pdrv->driver.name);
1168			/* fall-through */
1169		case EARLY_PLATFORM_ID_UNSET:
1170			match = NULL;
1171			break;
1172		default:
1173			match = early_platform_match(epdrv, match_id);
1174		}
1175
1176		if (match) {
1177			/*
1178			 * Set up a sensible init_name to enable
1179			 * dev_name() and others to be used before the
1180			 * rest of the driver core is initialized.
1181			 */
1182			if (!match->dev.init_name && slab_is_available()) {
1183				if (match->id != -1)
1184					match->dev.init_name =
1185						kasprintf(GFP_KERNEL, "%s.%d",
1186							  match->name,
1187							  match->id);
1188				else
1189					match->dev.init_name =
1190						kasprintf(GFP_KERNEL, "%s",
1191							  match->name);
1192
1193				if (!match->dev.init_name)
1194					return -ENOMEM;
1195			}
1196
1197			if (epdrv->pdrv->probe(match))
1198				pr_warning("%s: unable to probe %s early.\n",
1199					   class_str, match->name);
1200			else
1201				n++;
1202		}
1203
1204		if (n >= nr_probe)
1205			break;
1206	}
1207
1208	if (left)
1209		return n;
1210	else
1211		return -ENODEV;
1212}
1213
1214/**
1215 * early_platform_driver_probe - probe a class of registered drivers
1216 * @class_str: string to identify early platform driver class
1217 * @nr_probe: number of platform devices to successfully probe before exiting
1218 * @user_only: only probe user specified early platform devices
1219 *
1220 * Used by architecture code to probe registered early platform drivers
1221 * within a certain class. For probe to happen a registered early platform
1222 * device matching a registered early platform driver is needed.
1223 */
1224int __init early_platform_driver_probe(char *class_str,
1225				       int nr_probe,
1226				       int user_only)
1227{
1228	int k, n, i;
1229
1230	n = 0;
1231	for (i = -2; n < nr_probe; i++) {
1232		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1233
1234		if (k < 0)
1235			break;
1236
1237		n += k;
1238
1239		if (user_only)
1240			break;
1241	}
1242
1243	return n;
1244}
1245
1246/**
1247 * early_platform_cleanup - clean up early platform code
1248 */
1249void __init early_platform_cleanup(void)
1250{
1251	struct platform_device *pd, *pd2;
1252
1253	/* clean up the devres list used to chain devices */
1254	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1255				 dev.devres_head) {
1256		list_del(&pd->dev.devres_head);
1257		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1258	}
1259}
1260
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