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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
v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * platform.c - platform 'pseudo' bus for legacy devices
   4 *
   5 * Copyright (c) 2002-3 Patrick Mochel
   6 * Copyright (c) 2002-3 Open Source Development Labs
   7 *
 
 
   8 * Please see Documentation/driver-model/platform.txt for more
   9 * information.
  10 */
  11
  12#include <linux/string.h>
  13#include <linux/platform_device.h>
  14#include <linux/of_device.h>
  15#include <linux/of_irq.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/dma-mapping.h>
  19#include <linux/bootmem.h>
  20#include <linux/err.h>
  21#include <linux/slab.h>
  22#include <linux/pm_runtime.h>
  23#include <linux/pm_domain.h>
  24#include <linux/idr.h>
  25#include <linux/acpi.h>
  26#include <linux/clk/clk-conf.h>
  27#include <linux/limits.h>
  28#include <linux/property.h>
  29
  30#include "base.h"
  31#include "power/power.h"
  32
  33/* For automatically allocated device IDs */
  34static DEFINE_IDA(platform_devid_ida);
  35
  36struct device platform_bus = {
  37	.init_name	= "platform",
  38};
  39EXPORT_SYMBOL_GPL(platform_bus);
  40
  41/**
  42 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
  43 * @pdev: platform device
  44 *
  45 * This is called before platform_device_add() such that any pdev_archdata may
  46 * be setup before the platform_notifier is called.  So if a user needs to
  47 * manipulate any relevant information in the pdev_archdata they can do:
  48 *
  49 *	platform_device_alloc()
  50 *	... manipulate ...
  51 *	platform_device_add()
  52 *
  53 * And if they don't care they can just call platform_device_register() and
  54 * everything will just work out.
  55 */
  56void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
  57{
  58}
  59
  60/**
  61 * platform_get_resource - get a resource for a device
  62 * @dev: platform device
  63 * @type: resource type
  64 * @num: resource index
  65 */
  66struct resource *platform_get_resource(struct platform_device *dev,
  67				       unsigned int type, unsigned int num)
  68{
  69	int i;
  70
  71	for (i = 0; i < dev->num_resources; i++) {
  72		struct resource *r = &dev->resource[i];
  73
  74		if (type == resource_type(r) && num-- == 0)
  75			return r;
  76	}
  77	return NULL;
  78}
  79EXPORT_SYMBOL_GPL(platform_get_resource);
  80
  81/**
  82 * platform_get_irq - get an IRQ for a device
  83 * @dev: platform device
  84 * @num: IRQ number index
  85 */
  86int platform_get_irq(struct platform_device *dev, unsigned int num)
  87{
  88#ifdef CONFIG_SPARC
  89	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
  90	if (!dev || num >= dev->archdata.num_irqs)
  91		return -ENXIO;
  92	return dev->archdata.irqs[num];
  93#else
  94	struct resource *r;
  95	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
  96		int ret;
  97
  98		ret = of_irq_get(dev->dev.of_node, num);
  99		if (ret > 0 || ret == -EPROBE_DEFER)
 100			return ret;
 101	}
 102
 103	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 104	if (has_acpi_companion(&dev->dev)) {
 105		if (r && r->flags & IORESOURCE_DISABLED) {
 106			int ret;
 107
 108			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 109			if (ret)
 110				return ret;
 111		}
 112	}
 113
 114	/*
 115	 * The resources may pass trigger flags to the irqs that need
 116	 * to be set up. It so happens that the trigger flags for
 117	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 118	 * settings.
 119	 */
 120	if (r && r->flags & IORESOURCE_BITS) {
 121		struct irq_data *irqd;
 122
 123		irqd = irq_get_irq_data(r->start);
 124		if (!irqd)
 125			return -ENXIO;
 126		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 127	}
 128
 129	return r ? r->start : -ENXIO;
 130#endif
 131}
 132EXPORT_SYMBOL_GPL(platform_get_irq);
 133
 134/**
 135 * platform_irq_count - Count the number of IRQs a platform device uses
 136 * @dev: platform device
 137 *
 138 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 139 */
 140int platform_irq_count(struct platform_device *dev)
 141{
 142	int ret, nr = 0;
 143
 144	while ((ret = platform_get_irq(dev, nr)) >= 0)
 145		nr++;
 146
 147	if (ret == -EPROBE_DEFER)
 148		return ret;
 149
 150	return nr;
 151}
 152EXPORT_SYMBOL_GPL(platform_irq_count);
 153
 154/**
 155 * platform_get_resource_byname - get a resource for a device by name
 156 * @dev: platform device
 157 * @type: resource type
 158 * @name: resource name
 159 */
 160struct resource *platform_get_resource_byname(struct platform_device *dev,
 161					      unsigned int type,
 162					      const char *name)
 163{
 164	int i;
 165
 166	for (i = 0; i < dev->num_resources; i++) {
 167		struct resource *r = &dev->resource[i];
 168
 169		if (unlikely(!r->name))
 170			continue;
 171
 172		if (type == resource_type(r) && !strcmp(r->name, name))
 173			return r;
 174	}
 175	return NULL;
 176}
 177EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 178
 179/**
 180 * platform_get_irq_byname - get an IRQ for a device by name
 181 * @dev: platform device
 182 * @name: IRQ name
 183 */
 184int platform_get_irq_byname(struct platform_device *dev, const char *name)
 185{
 186	struct resource *r;
 
 187
 188	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 189		int ret;
 190
 191		ret = of_irq_get_byname(dev->dev.of_node, name);
 192		if (ret > 0 || ret == -EPROBE_DEFER)
 193			return ret;
 194	}
 195
 196	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 197	return r ? r->start : -ENXIO;
 198}
 199EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 200
 201/**
 202 * platform_add_devices - add a numbers of platform devices
 203 * @devs: array of platform devices to add
 204 * @num: number of platform devices in array
 205 */
 206int platform_add_devices(struct platform_device **devs, int num)
 207{
 208	int i, ret = 0;
 209
 210	for (i = 0; i < num; i++) {
 211		ret = platform_device_register(devs[i]);
 212		if (ret) {
 213			while (--i >= 0)
 214				platform_device_unregister(devs[i]);
 215			break;
 216		}
 217	}
 218
 219	return ret;
 220}
 221EXPORT_SYMBOL_GPL(platform_add_devices);
 222
 223struct platform_object {
 224	struct platform_device pdev;
 225	char name[];
 226};
 227
 228/**
 229 * platform_device_put - destroy a platform device
 230 * @pdev: platform device to free
 231 *
 232 * Free all memory associated with a platform device.  This function must
 233 * _only_ be externally called in error cases.  All other usage is a bug.
 234 */
 235void platform_device_put(struct platform_device *pdev)
 236{
 237	if (pdev)
 238		put_device(&pdev->dev);
 239}
 240EXPORT_SYMBOL_GPL(platform_device_put);
 241
 242static void platform_device_release(struct device *dev)
 243{
 244	struct platform_object *pa = container_of(dev, struct platform_object,
 245						  pdev.dev);
 246
 247	of_device_node_put(&pa->pdev.dev);
 248	kfree(pa->pdev.dev.platform_data);
 249	kfree(pa->pdev.mfd_cell);
 250	kfree(pa->pdev.resource);
 251	kfree(pa->pdev.driver_override);
 252	kfree(pa);
 253}
 254
 255/**
 256 * platform_device_alloc - create a platform device
 257 * @name: base name of the device we're adding
 258 * @id: instance id
 259 *
 260 * Create a platform device object which can have other objects attached
 261 * to it, and which will have attached objects freed when it is released.
 262 */
 263struct platform_device *platform_device_alloc(const char *name, int id)
 264{
 265	struct platform_object *pa;
 266
 267	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 268	if (pa) {
 269		strcpy(pa->name, name);
 270		pa->pdev.name = pa->name;
 271		pa->pdev.id = id;
 272		device_initialize(&pa->pdev.dev);
 273		pa->pdev.dev.release = platform_device_release;
 274		arch_setup_pdev_archdata(&pa->pdev);
 275	}
 276
 277	return pa ? &pa->pdev : NULL;
 278}
 279EXPORT_SYMBOL_GPL(platform_device_alloc);
 280
 281/**
 282 * platform_device_add_resources - add resources to a platform device
 283 * @pdev: platform device allocated by platform_device_alloc to add resources to
 284 * @res: set of resources that needs to be allocated for the device
 285 * @num: number of resources
 286 *
 287 * Add a copy of the resources to the platform device.  The memory
 288 * associated with the resources will be freed when the platform device is
 289 * released.
 290 */
 291int platform_device_add_resources(struct platform_device *pdev,
 292				  const struct resource *res, unsigned int num)
 293{
 294	struct resource *r = NULL;
 295
 296	if (res) {
 297		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 298		if (!r)
 299			return -ENOMEM;
 300	}
 301
 302	kfree(pdev->resource);
 303	pdev->resource = r;
 304	pdev->num_resources = num;
 305	return 0;
 306}
 307EXPORT_SYMBOL_GPL(platform_device_add_resources);
 308
 309/**
 310 * platform_device_add_data - add platform-specific data to a platform device
 311 * @pdev: platform device allocated by platform_device_alloc to add resources to
 312 * @data: platform specific data for this platform device
 313 * @size: size of platform specific data
 314 *
 315 * Add a copy of platform specific data to the platform device's
 316 * platform_data pointer.  The memory associated with the platform data
 317 * will be freed when the platform device is released.
 318 */
 319int platform_device_add_data(struct platform_device *pdev, const void *data,
 320			     size_t size)
 321{
 322	void *d = NULL;
 323
 324	if (data) {
 325		d = kmemdup(data, size, GFP_KERNEL);
 326		if (!d)
 327			return -ENOMEM;
 328	}
 329
 330	kfree(pdev->dev.platform_data);
 331	pdev->dev.platform_data = d;
 332	return 0;
 333}
 334EXPORT_SYMBOL_GPL(platform_device_add_data);
 335
 336/**
 337 * platform_device_add_properties - add built-in properties to a platform device
 338 * @pdev: platform device to add properties to
 339 * @properties: null terminated array of properties to add
 340 *
 341 * The function will take deep copy of @properties and attach the copy to the
 342 * platform device. The memory associated with properties will be freed when the
 343 * platform device is released.
 344 */
 345int platform_device_add_properties(struct platform_device *pdev,
 346				   const struct property_entry *properties)
 347{
 348	return device_add_properties(&pdev->dev, properties);
 349}
 350EXPORT_SYMBOL_GPL(platform_device_add_properties);
 351
 352/**
 353 * platform_device_add - add a platform device to device hierarchy
 354 * @pdev: platform device we're adding
 355 *
 356 * This is part 2 of platform_device_register(), though may be called
 357 * separately _iff_ pdev was allocated by platform_device_alloc().
 358 */
 359int platform_device_add(struct platform_device *pdev)
 360{
 361	int i, ret;
 362
 363	if (!pdev)
 364		return -EINVAL;
 365
 366	if (!pdev->dev.parent)
 367		pdev->dev.parent = &platform_bus;
 368
 369	pdev->dev.bus = &platform_bus_type;
 370
 371	switch (pdev->id) {
 372	default:
 373		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 374		break;
 375	case PLATFORM_DEVID_NONE:
 376		dev_set_name(&pdev->dev, "%s", pdev->name);
 377		break;
 378	case PLATFORM_DEVID_AUTO:
 379		/*
 380		 * Automatically allocated device ID. We mark it as such so
 381		 * that we remember it must be freed, and we append a suffix
 382		 * to avoid namespace collision with explicit IDs.
 383		 */
 384		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 385		if (ret < 0)
 386			goto err_out;
 387		pdev->id = ret;
 388		pdev->id_auto = true;
 389		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 390		break;
 391	}
 392
 393	for (i = 0; i < pdev->num_resources; i++) {
 394		struct resource *p, *r = &pdev->resource[i];
 395
 396		if (r->name == NULL)
 397			r->name = dev_name(&pdev->dev);
 398
 399		p = r->parent;
 400		if (!p) {
 401			if (resource_type(r) == IORESOURCE_MEM)
 402				p = &iomem_resource;
 403			else if (resource_type(r) == IORESOURCE_IO)
 404				p = &ioport_resource;
 405		}
 406
 407		if (p && insert_resource(p, r)) {
 408			dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 
 
 409			ret = -EBUSY;
 410			goto failed;
 411		}
 412	}
 413
 414	pr_debug("Registering platform device '%s'. Parent at %s\n",
 415		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 416
 417	ret = device_add(&pdev->dev);
 418	if (ret == 0)
 419		return ret;
 420
 421 failed:
 422	if (pdev->id_auto) {
 423		ida_simple_remove(&platform_devid_ida, pdev->id);
 424		pdev->id = PLATFORM_DEVID_AUTO;
 425	}
 426
 427	while (--i >= 0) {
 428		struct resource *r = &pdev->resource[i];
 429		if (r->parent)
 
 
 430			release_resource(r);
 431	}
 432
 433 err_out:
 434	return ret;
 435}
 436EXPORT_SYMBOL_GPL(platform_device_add);
 437
 438/**
 439 * platform_device_del - remove a platform-level device
 440 * @pdev: platform device we're removing
 441 *
 442 * Note that this function will also release all memory- and port-based
 443 * resources owned by the device (@dev->resource).  This function must
 444 * _only_ be externally called in error cases.  All other usage is a bug.
 445 */
 446void platform_device_del(struct platform_device *pdev)
 447{
 448	int i;
 449
 450	if (pdev) {
 451		device_remove_properties(&pdev->dev);
 452		device_del(&pdev->dev);
 453
 454		if (pdev->id_auto) {
 455			ida_simple_remove(&platform_devid_ida, pdev->id);
 456			pdev->id = PLATFORM_DEVID_AUTO;
 457		}
 458
 459		for (i = 0; i < pdev->num_resources; i++) {
 460			struct resource *r = &pdev->resource[i];
 461			if (r->parent)
 
 
 462				release_resource(r);
 463		}
 464	}
 465}
 466EXPORT_SYMBOL_GPL(platform_device_del);
 467
 468/**
 469 * platform_device_register - add a platform-level device
 470 * @pdev: platform device we're adding
 471 */
 472int platform_device_register(struct platform_device *pdev)
 473{
 474	device_initialize(&pdev->dev);
 475	arch_setup_pdev_archdata(pdev);
 476	return platform_device_add(pdev);
 477}
 478EXPORT_SYMBOL_GPL(platform_device_register);
 479
 480/**
 481 * platform_device_unregister - unregister a platform-level device
 482 * @pdev: platform device we're unregistering
 483 *
 484 * Unregistration is done in 2 steps. First we release all resources
 485 * and remove it from the subsystem, then we drop reference count by
 486 * calling platform_device_put().
 487 */
 488void platform_device_unregister(struct platform_device *pdev)
 489{
 490	platform_device_del(pdev);
 491	platform_device_put(pdev);
 492}
 493EXPORT_SYMBOL_GPL(platform_device_unregister);
 494
 495/**
 496 * platform_device_register_full - add a platform-level device with
 497 * resources and platform-specific data
 498 *
 499 * @pdevinfo: data used to create device
 
 
 
 
 
 
 500 *
 501 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 502 */
 503struct platform_device *platform_device_register_full(
 504		const struct platform_device_info *pdevinfo)
 
 
 
 505{
 506	int ret = -ENOMEM;
 507	struct platform_device *pdev;
 508
 509	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 510	if (!pdev)
 511		goto err_alloc;
 512
 513	pdev->dev.parent = pdevinfo->parent;
 514	pdev->dev.fwnode = pdevinfo->fwnode;
 515
 516	if (pdevinfo->dma_mask) {
 517		/*
 518		 * This memory isn't freed when the device is put,
 519		 * I don't have a nice idea for that though.  Conceptually
 520		 * dma_mask in struct device should not be a pointer.
 521		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 522		 */
 523		pdev->dev.dma_mask =
 524			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 525		if (!pdev->dev.dma_mask)
 526			goto err;
 527
 528		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 529		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 530	}
 531
 532	ret = platform_device_add_resources(pdev,
 533			pdevinfo->res, pdevinfo->num_res);
 534	if (ret)
 535		goto err;
 536
 537	ret = platform_device_add_data(pdev,
 538			pdevinfo->data, pdevinfo->size_data);
 539	if (ret)
 540		goto err;
 541
 542	if (pdevinfo->properties) {
 543		ret = platform_device_add_properties(pdev,
 544						     pdevinfo->properties);
 545		if (ret)
 546			goto err;
 547	}
 548
 549	ret = platform_device_add(pdev);
 550	if (ret) {
 551err:
 552		ACPI_COMPANION_SET(&pdev->dev, NULL);
 553		kfree(pdev->dev.dma_mask);
 554
 555err_alloc:
 556		platform_device_put(pdev);
 557		return ERR_PTR(ret);
 558	}
 559
 560	return pdev;
 561}
 562EXPORT_SYMBOL_GPL(platform_device_register_full);
 563
 564static int platform_drv_probe(struct device *_dev)
 565{
 566	struct platform_driver *drv = to_platform_driver(_dev->driver);
 567	struct platform_device *dev = to_platform_device(_dev);
 568	int ret;
 569
 570	ret = of_clk_set_defaults(_dev->of_node, false);
 571	if (ret < 0)
 572		return ret;
 573
 574	ret = dev_pm_domain_attach(_dev, true);
 575	if (ret != -EPROBE_DEFER) {
 576		if (drv->probe) {
 577			ret = drv->probe(dev);
 578			if (ret)
 579				dev_pm_domain_detach(_dev, true);
 580		} else {
 581			/* don't fail if just dev_pm_domain_attach failed */
 582			ret = 0;
 583		}
 584	}
 585
 586	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 587		dev_warn(_dev, "probe deferral not supported\n");
 588		ret = -ENXIO;
 589	}
 590
 591	return ret;
 592}
 593
 594static int platform_drv_probe_fail(struct device *_dev)
 595{
 596	return -ENXIO;
 597}
 598
 599static int platform_drv_remove(struct device *_dev)
 600{
 601	struct platform_driver *drv = to_platform_driver(_dev->driver);
 602	struct platform_device *dev = to_platform_device(_dev);
 603	int ret = 0;
 604
 605	if (drv->remove)
 606		ret = drv->remove(dev);
 607	dev_pm_domain_detach(_dev, true);
 608
 609	return ret;
 610}
 611
 612static void platform_drv_shutdown(struct device *_dev)
 613{
 614	struct platform_driver *drv = to_platform_driver(_dev->driver);
 615	struct platform_device *dev = to_platform_device(_dev);
 616
 617	if (drv->shutdown)
 618		drv->shutdown(dev);
 619}
 620
 621/**
 622 * __platform_driver_register - register a driver for platform-level devices
 623 * @drv: platform driver structure
 624 * @owner: owning module/driver
 625 */
 626int __platform_driver_register(struct platform_driver *drv,
 627				struct module *owner)
 628{
 629	drv->driver.owner = owner;
 630	drv->driver.bus = &platform_bus_type;
 631	drv->driver.probe = platform_drv_probe;
 632	drv->driver.remove = platform_drv_remove;
 633	drv->driver.shutdown = platform_drv_shutdown;
 
 
 
 634
 635	return driver_register(&drv->driver);
 636}
 637EXPORT_SYMBOL_GPL(__platform_driver_register);
 638
 639/**
 640 * platform_driver_unregister - unregister a driver for platform-level devices
 641 * @drv: platform driver structure
 642 */
 643void platform_driver_unregister(struct platform_driver *drv)
 644{
 645	driver_unregister(&drv->driver);
 646}
 647EXPORT_SYMBOL_GPL(platform_driver_unregister);
 648
 649/**
 650 * __platform_driver_probe - register driver for non-hotpluggable device
 651 * @drv: platform driver structure
 652 * @probe: the driver probe routine, probably from an __init section
 653 * @module: module which will be the owner of the driver
 654 *
 655 * Use this instead of platform_driver_register() when you know the device
 656 * is not hotpluggable and has already been registered, and you want to
 657 * remove its run-once probe() infrastructure from memory after the driver
 658 * has bound to the device.
 659 *
 660 * One typical use for this would be with drivers for controllers integrated
 661 * into system-on-chip processors, where the controller devices have been
 662 * configured as part of board setup.
 663 *
 664 * Note that this is incompatible with deferred probing.
 665 *
 666 * Returns zero if the driver registered and bound to a device, else returns
 667 * a negative error code and with the driver not registered.
 668 */
 669int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 670		int (*probe)(struct platform_device *), struct module *module)
 671{
 672	int retval, code;
 673
 674	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 675		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 676			 drv->driver.name, __func__);
 677		return -EINVAL;
 678	}
 679
 680	/*
 681	 * We have to run our probes synchronously because we check if
 682	 * we find any devices to bind to and exit with error if there
 683	 * are any.
 684	 */
 685	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 686
 687	/*
 688	 * Prevent driver from requesting probe deferral to avoid further
 689	 * futile probe attempts.
 690	 */
 691	drv->prevent_deferred_probe = true;
 692
 693	/* make sure driver won't have bind/unbind attributes */
 694	drv->driver.suppress_bind_attrs = true;
 695
 696	/* temporary section violation during probe() */
 697	drv->probe = probe;
 698	retval = code = __platform_driver_register(drv, module);
 699
 700	/*
 701	 * Fixup that section violation, being paranoid about code scanning
 702	 * the list of drivers in order to probe new devices.  Check to see
 703	 * if the probe was successful, and make sure any forced probes of
 704	 * new devices fail.
 705	 */
 706	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 707	drv->probe = NULL;
 708	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 709		retval = -ENODEV;
 710	drv->driver.probe = platform_drv_probe_fail;
 711	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 712
 713	if (code != retval)
 714		platform_driver_unregister(drv);
 715	return retval;
 716}
 717EXPORT_SYMBOL_GPL(__platform_driver_probe);
 718
 719/**
 720 * __platform_create_bundle - register driver and create corresponding device
 721 * @driver: platform driver structure
 722 * @probe: the driver probe routine, probably from an __init section
 723 * @res: set of resources that needs to be allocated for the device
 724 * @n_res: number of resources
 725 * @data: platform specific data for this platform device
 726 * @size: size of platform specific data
 727 * @module: module which will be the owner of the driver
 728 *
 729 * Use this in legacy-style modules that probe hardware directly and
 730 * register a single platform device and corresponding platform driver.
 731 *
 732 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 733 */
 734struct platform_device * __init_or_module __platform_create_bundle(
 735			struct platform_driver *driver,
 736			int (*probe)(struct platform_device *),
 737			struct resource *res, unsigned int n_res,
 738			const void *data, size_t size, struct module *module)
 739{
 740	struct platform_device *pdev;
 741	int error;
 742
 743	pdev = platform_device_alloc(driver->driver.name, -1);
 744	if (!pdev) {
 745		error = -ENOMEM;
 746		goto err_out;
 747	}
 748
 749	error = platform_device_add_resources(pdev, res, n_res);
 750	if (error)
 751		goto err_pdev_put;
 752
 753	error = platform_device_add_data(pdev, data, size);
 754	if (error)
 755		goto err_pdev_put;
 756
 757	error = platform_device_add(pdev);
 758	if (error)
 759		goto err_pdev_put;
 760
 761	error = __platform_driver_probe(driver, probe, module);
 762	if (error)
 763		goto err_pdev_del;
 764
 765	return pdev;
 766
 767err_pdev_del:
 768	platform_device_del(pdev);
 769err_pdev_put:
 770	platform_device_put(pdev);
 771err_out:
 772	return ERR_PTR(error);
 773}
 774EXPORT_SYMBOL_GPL(__platform_create_bundle);
 775
 776/**
 777 * __platform_register_drivers - register an array of platform drivers
 778 * @drivers: an array of drivers to register
 779 * @count: the number of drivers to register
 780 * @owner: module owning the drivers
 781 *
 782 * Registers platform drivers specified by an array. On failure to register a
 783 * driver, all previously registered drivers will be unregistered. Callers of
 784 * this API should use platform_unregister_drivers() to unregister drivers in
 785 * the reverse order.
 786 *
 787 * Returns: 0 on success or a negative error code on failure.
 788 */
 789int __platform_register_drivers(struct platform_driver * const *drivers,
 790				unsigned int count, struct module *owner)
 791{
 792	unsigned int i;
 793	int err;
 794
 795	for (i = 0; i < count; i++) {
 796		pr_debug("registering platform driver %ps\n", drivers[i]);
 797
 798		err = __platform_driver_register(drivers[i], owner);
 799		if (err < 0) {
 800			pr_err("failed to register platform driver %ps: %d\n",
 801			       drivers[i], err);
 802			goto error;
 803		}
 804	}
 805
 806	return 0;
 807
 808error:
 809	while (i--) {
 810		pr_debug("unregistering platform driver %ps\n", drivers[i]);
 811		platform_driver_unregister(drivers[i]);
 812	}
 813
 814	return err;
 815}
 816EXPORT_SYMBOL_GPL(__platform_register_drivers);
 817
 818/**
 819 * platform_unregister_drivers - unregister an array of platform drivers
 820 * @drivers: an array of drivers to unregister
 821 * @count: the number of drivers to unregister
 822 *
 823 * Unegisters platform drivers specified by an array. This is typically used
 824 * to complement an earlier call to platform_register_drivers(). Drivers are
 825 * unregistered in the reverse order in which they were registered.
 826 */
 827void platform_unregister_drivers(struct platform_driver * const *drivers,
 828				 unsigned int count)
 829{
 830	while (count--) {
 831		pr_debug("unregistering platform driver %ps\n", drivers[count]);
 832		platform_driver_unregister(drivers[count]);
 833	}
 834}
 835EXPORT_SYMBOL_GPL(platform_unregister_drivers);
 836
 837/* modalias support enables more hands-off userspace setup:
 838 * (a) environment variable lets new-style hotplug events work once system is
 839 *     fully running:  "modprobe $MODALIAS"
 840 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 841 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 842 */
 843static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 844			     char *buf)
 845{
 846	struct platform_device	*pdev = to_platform_device(dev);
 847	int len;
 848
 849	len = of_device_modalias(dev, buf, PAGE_SIZE);
 850	if (len != -ENODEV)
 851		return len;
 852
 853	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 854	if (len != -ENODEV)
 855		return len;
 856
 857	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 858
 859	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 860}
 861static DEVICE_ATTR_RO(modalias);
 862
 863static ssize_t driver_override_store(struct device *dev,
 864				     struct device_attribute *attr,
 865				     const char *buf, size_t count)
 866{
 867	struct platform_device *pdev = to_platform_device(dev);
 868	char *driver_override, *old, *cp;
 869
 870	/* We need to keep extra room for a newline */
 871	if (count >= (PAGE_SIZE - 1))
 872		return -EINVAL;
 873
 874	driver_override = kstrndup(buf, count, GFP_KERNEL);
 875	if (!driver_override)
 876		return -ENOMEM;
 877
 878	cp = strchr(driver_override, '\n');
 879	if (cp)
 880		*cp = '\0';
 881
 882	device_lock(dev);
 883	old = pdev->driver_override;
 884	if (strlen(driver_override)) {
 885		pdev->driver_override = driver_override;
 886	} else {
 887		kfree(driver_override);
 888		pdev->driver_override = NULL;
 889	}
 890	device_unlock(dev);
 891
 892	kfree(old);
 893
 894	return count;
 895}
 896
 897static ssize_t driver_override_show(struct device *dev,
 898				    struct device_attribute *attr, char *buf)
 899{
 900	struct platform_device *pdev = to_platform_device(dev);
 901	ssize_t len;
 902
 903	device_lock(dev);
 904	len = sprintf(buf, "%s\n", pdev->driver_override);
 905	device_unlock(dev);
 906	return len;
 907}
 908static DEVICE_ATTR_RW(driver_override);
 909
 910
 911static struct attribute *platform_dev_attrs[] = {
 912	&dev_attr_modalias.attr,
 913	&dev_attr_driver_override.attr,
 914	NULL,
 915};
 916ATTRIBUTE_GROUPS(platform_dev);
 917
 918static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 919{
 920	struct platform_device	*pdev = to_platform_device(dev);
 921	int rc;
 922
 923	/* Some devices have extra OF data and an OF-style MODALIAS */
 924	rc = of_device_uevent_modalias(dev, env);
 925	if (rc != -ENODEV)
 926		return rc;
 927
 928	rc = acpi_device_uevent_modalias(dev, env);
 929	if (rc != -ENODEV)
 930		return rc;
 931
 932	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
 933			pdev->name);
 934	return 0;
 935}
 936
 937static const struct platform_device_id *platform_match_id(
 938			const struct platform_device_id *id,
 939			struct platform_device *pdev)
 940{
 941	while (id->name[0]) {
 942		if (strcmp(pdev->name, id->name) == 0) {
 943			pdev->id_entry = id;
 944			return id;
 945		}
 946		id++;
 947	}
 948	return NULL;
 949}
 950
 951/**
 952 * platform_match - bind platform device to platform driver.
 953 * @dev: device.
 954 * @drv: driver.
 955 *
 956 * Platform device IDs are assumed to be encoded like this:
 957 * "<name><instance>", where <name> is a short description of the type of
 958 * device, like "pci" or "floppy", and <instance> is the enumerated
 959 * instance of the device, like '0' or '42'.  Driver IDs are simply
 960 * "<name>".  So, extract the <name> from the platform_device structure,
 961 * and compare it against the name of the driver. Return whether they match
 962 * or not.
 963 */
 964static int platform_match(struct device *dev, struct device_driver *drv)
 965{
 966	struct platform_device *pdev = to_platform_device(dev);
 967	struct platform_driver *pdrv = to_platform_driver(drv);
 968
 969	/* When driver_override is set, only bind to the matching driver */
 970	if (pdev->driver_override)
 971		return !strcmp(pdev->driver_override, drv->name);
 972
 973	/* Attempt an OF style match first */
 974	if (of_driver_match_device(dev, drv))
 975		return 1;
 976
 977	/* Then try ACPI style match */
 978	if (acpi_driver_match_device(dev, drv))
 979		return 1;
 980
 981	/* Then try to match against the id table */
 982	if (pdrv->id_table)
 983		return platform_match_id(pdrv->id_table, pdev) != NULL;
 984
 985	/* fall-back to driver name match */
 986	return (strcmp(pdev->name, drv->name) == 0);
 987}
 988
 989#ifdef CONFIG_PM_SLEEP
 990
 991static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
 992{
 993	struct platform_driver *pdrv = to_platform_driver(dev->driver);
 994	struct platform_device *pdev = to_platform_device(dev);
 995	int ret = 0;
 996
 997	if (dev->driver && pdrv->suspend)
 998		ret = pdrv->suspend(pdev, mesg);
 999
1000	return ret;
1001}
1002
1003static int platform_legacy_resume(struct device *dev)
1004{
1005	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1006	struct platform_device *pdev = to_platform_device(dev);
1007	int ret = 0;
1008
1009	if (dev->driver && pdrv->resume)
1010		ret = pdrv->resume(pdev);
1011
1012	return ret;
1013}
1014
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1015#endif /* CONFIG_PM_SLEEP */
1016
1017#ifdef CONFIG_SUSPEND
1018
1019int platform_pm_suspend(struct device *dev)
1020{
1021	struct device_driver *drv = dev->driver;
1022	int ret = 0;
1023
1024	if (!drv)
1025		return 0;
1026
1027	if (drv->pm) {
1028		if (drv->pm->suspend)
1029			ret = drv->pm->suspend(dev);
1030	} else {
1031		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1032	}
1033
1034	return ret;
1035}
1036
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1037int platform_pm_resume(struct device *dev)
1038{
1039	struct device_driver *drv = dev->driver;
1040	int ret = 0;
1041
1042	if (!drv)
1043		return 0;
1044
1045	if (drv->pm) {
1046		if (drv->pm->resume)
1047			ret = drv->pm->resume(dev);
1048	} else {
1049		ret = platform_legacy_resume(dev);
1050	}
1051
1052	return ret;
1053}
1054
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1055#endif /* CONFIG_SUSPEND */
1056
1057#ifdef CONFIG_HIBERNATE_CALLBACKS
1058
1059int platform_pm_freeze(struct device *dev)
1060{
1061	struct device_driver *drv = dev->driver;
1062	int ret = 0;
1063
1064	if (!drv)
1065		return 0;
1066
1067	if (drv->pm) {
1068		if (drv->pm->freeze)
1069			ret = drv->pm->freeze(dev);
1070	} else {
1071		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1072	}
1073
1074	return ret;
1075}
1076
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1077int platform_pm_thaw(struct device *dev)
1078{
1079	struct device_driver *drv = dev->driver;
1080	int ret = 0;
1081
1082	if (!drv)
1083		return 0;
1084
1085	if (drv->pm) {
1086		if (drv->pm->thaw)
1087			ret = drv->pm->thaw(dev);
1088	} else {
1089		ret = platform_legacy_resume(dev);
1090	}
1091
1092	return ret;
1093}
1094
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1095int platform_pm_poweroff(struct device *dev)
1096{
1097	struct device_driver *drv = dev->driver;
1098	int ret = 0;
1099
1100	if (!drv)
1101		return 0;
1102
1103	if (drv->pm) {
1104		if (drv->pm->poweroff)
1105			ret = drv->pm->poweroff(dev);
1106	} else {
1107		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1108	}
1109
1110	return ret;
1111}
1112
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1113int platform_pm_restore(struct device *dev)
1114{
1115	struct device_driver *drv = dev->driver;
1116	int ret = 0;
1117
1118	if (!drv)
1119		return 0;
1120
1121	if (drv->pm) {
1122		if (drv->pm->restore)
1123			ret = drv->pm->restore(dev);
1124	} else {
1125		ret = platform_legacy_resume(dev);
1126	}
1127
1128	return ret;
1129}
1130
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1131#endif /* CONFIG_HIBERNATE_CALLBACKS */
1132
1133static const struct dev_pm_ops platform_dev_pm_ops = {
1134	.runtime_suspend = pm_generic_runtime_suspend,
1135	.runtime_resume = pm_generic_runtime_resume,
 
1136	USE_PLATFORM_PM_SLEEP_OPS
1137};
1138
1139struct bus_type platform_bus_type = {
1140	.name		= "platform",
1141	.dev_groups	= platform_dev_groups,
1142	.match		= platform_match,
1143	.uevent		= platform_uevent,
1144	.pm		= &platform_dev_pm_ops,
1145	.force_dma	= true,
1146};
1147EXPORT_SYMBOL_GPL(platform_bus_type);
1148
1149int __init platform_bus_init(void)
1150{
1151	int error;
1152
1153	early_platform_cleanup();
1154
1155	error = device_register(&platform_bus);
1156	if (error) {
1157		put_device(&platform_bus);
1158		return error;
1159	}
1160	error =  bus_register(&platform_bus_type);
1161	if (error)
1162		device_unregister(&platform_bus);
1163	of_platform_register_reconfig_notifier();
1164	return error;
1165}
1166
1167#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1168u64 dma_get_required_mask(struct device *dev)
1169{
1170	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1171	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1172	u64 mask;
1173
1174	if (!high_totalram) {
1175		/* convert to mask just covering totalram */
1176		low_totalram = (1 << (fls(low_totalram) - 1));
1177		low_totalram += low_totalram - 1;
1178		mask = low_totalram;
1179	} else {
1180		high_totalram = (1 << (fls(high_totalram) - 1));
1181		high_totalram += high_totalram - 1;
1182		mask = (((u64)high_totalram) << 32) + 0xffffffff;
1183	}
1184	return mask;
1185}
1186EXPORT_SYMBOL_GPL(dma_get_required_mask);
1187#endif
1188
1189static __initdata LIST_HEAD(early_platform_driver_list);
1190static __initdata LIST_HEAD(early_platform_device_list);
1191
1192/**
1193 * early_platform_driver_register - register early platform driver
1194 * @epdrv: early_platform driver structure
1195 * @buf: string passed from early_param()
1196 *
1197 * Helper function for early_platform_init() / early_platform_init_buffer()
1198 */
1199int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1200					  char *buf)
1201{
1202	char *tmp;
1203	int n;
1204
1205	/* Simply add the driver to the end of the global list.
1206	 * Drivers will by default be put on the list in compiled-in order.
1207	 */
1208	if (!epdrv->list.next) {
1209		INIT_LIST_HEAD(&epdrv->list);
1210		list_add_tail(&epdrv->list, &early_platform_driver_list);
1211	}
1212
1213	/* If the user has specified device then make sure the driver
1214	 * gets prioritized. The driver of the last device specified on
1215	 * command line will be put first on the list.
1216	 */
1217	n = strlen(epdrv->pdrv->driver.name);
1218	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1219		list_move(&epdrv->list, &early_platform_driver_list);
1220
1221		/* Allow passing parameters after device name */
1222		if (buf[n] == '\0' || buf[n] == ',')
1223			epdrv->requested_id = -1;
1224		else {
1225			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1226							     &tmp, 10);
1227
1228			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1229				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1230				n = 0;
1231			} else
1232				n += strcspn(&buf[n + 1], ",") + 1;
1233		}
1234
1235		if (buf[n] == ',')
1236			n++;
1237
1238		if (epdrv->bufsize) {
1239			memcpy(epdrv->buffer, &buf[n],
1240			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1241			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1242		}
1243	}
1244
1245	return 0;
1246}
1247
1248/**
1249 * early_platform_add_devices - adds a number of early platform devices
1250 * @devs: array of early platform devices to add
1251 * @num: number of early platform devices in array
1252 *
1253 * Used by early architecture code to register early platform devices and
1254 * their platform data.
1255 */
1256void __init early_platform_add_devices(struct platform_device **devs, int num)
1257{
1258	struct device *dev;
1259	int i;
1260
1261	/* simply add the devices to list */
1262	for (i = 0; i < num; i++) {
1263		dev = &devs[i]->dev;
1264
1265		if (!dev->devres_head.next) {
1266			pm_runtime_early_init(dev);
1267			INIT_LIST_HEAD(&dev->devres_head);
1268			list_add_tail(&dev->devres_head,
1269				      &early_platform_device_list);
1270		}
1271	}
1272}
1273
1274/**
1275 * early_platform_driver_register_all - register early platform drivers
1276 * @class_str: string to identify early platform driver class
1277 *
1278 * Used by architecture code to register all early platform drivers
1279 * for a certain class. If omitted then only early platform drivers
1280 * with matching kernel command line class parameters will be registered.
1281 */
1282void __init early_platform_driver_register_all(char *class_str)
1283{
1284	/* The "class_str" parameter may or may not be present on the kernel
1285	 * command line. If it is present then there may be more than one
1286	 * matching parameter.
1287	 *
1288	 * Since we register our early platform drivers using early_param()
1289	 * we need to make sure that they also get registered in the case
1290	 * when the parameter is missing from the kernel command line.
1291	 *
1292	 * We use parse_early_options() to make sure the early_param() gets
1293	 * called at least once. The early_param() may be called more than
1294	 * once since the name of the preferred device may be specified on
1295	 * the kernel command line. early_platform_driver_register() handles
1296	 * this case for us.
1297	 */
1298	parse_early_options(class_str);
1299}
1300
1301/**
1302 * early_platform_match - find early platform device matching driver
1303 * @epdrv: early platform driver structure
1304 * @id: id to match against
1305 */
1306static struct platform_device * __init
1307early_platform_match(struct early_platform_driver *epdrv, int id)
1308{
1309	struct platform_device *pd;
1310
1311	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1312		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1313			if (pd->id == id)
1314				return pd;
1315
1316	return NULL;
1317}
1318
1319/**
1320 * early_platform_left - check if early platform driver has matching devices
1321 * @epdrv: early platform driver structure
1322 * @id: return true if id or above exists
1323 */
1324static int __init early_platform_left(struct early_platform_driver *epdrv,
1325				       int id)
1326{
1327	struct platform_device *pd;
1328
1329	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1330		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1331			if (pd->id >= id)
1332				return 1;
1333
1334	return 0;
1335}
1336
1337/**
1338 * early_platform_driver_probe_id - probe drivers matching class_str and id
1339 * @class_str: string to identify early platform driver class
1340 * @id: id to match against
1341 * @nr_probe: number of platform devices to successfully probe before exiting
1342 */
1343static int __init early_platform_driver_probe_id(char *class_str,
1344						 int id,
1345						 int nr_probe)
1346{
1347	struct early_platform_driver *epdrv;
1348	struct platform_device *match;
1349	int match_id;
1350	int n = 0;
1351	int left = 0;
1352
1353	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1354		/* only use drivers matching our class_str */
1355		if (strcmp(class_str, epdrv->class_str))
1356			continue;
1357
1358		if (id == -2) {
1359			match_id = epdrv->requested_id;
1360			left = 1;
1361
1362		} else {
1363			match_id = id;
1364			left += early_platform_left(epdrv, id);
1365
1366			/* skip requested id */
1367			switch (epdrv->requested_id) {
1368			case EARLY_PLATFORM_ID_ERROR:
1369			case EARLY_PLATFORM_ID_UNSET:
1370				break;
1371			default:
1372				if (epdrv->requested_id == id)
1373					match_id = EARLY_PLATFORM_ID_UNSET;
1374			}
1375		}
1376
1377		switch (match_id) {
1378		case EARLY_PLATFORM_ID_ERROR:
1379			pr_warn("%s: unable to parse %s parameter\n",
1380				class_str, epdrv->pdrv->driver.name);
1381			/* fall-through */
1382		case EARLY_PLATFORM_ID_UNSET:
1383			match = NULL;
1384			break;
1385		default:
1386			match = early_platform_match(epdrv, match_id);
1387		}
1388
1389		if (match) {
1390			/*
1391			 * Set up a sensible init_name to enable
1392			 * dev_name() and others to be used before the
1393			 * rest of the driver core is initialized.
1394			 */
1395			if (!match->dev.init_name && slab_is_available()) {
1396				if (match->id != -1)
1397					match->dev.init_name =
1398						kasprintf(GFP_KERNEL, "%s.%d",
1399							  match->name,
1400							  match->id);
1401				else
1402					match->dev.init_name =
1403						kasprintf(GFP_KERNEL, "%s",
1404							  match->name);
1405
1406				if (!match->dev.init_name)
1407					return -ENOMEM;
1408			}
1409
1410			if (epdrv->pdrv->probe(match))
1411				pr_warn("%s: unable to probe %s early.\n",
1412					class_str, match->name);
1413			else
1414				n++;
1415		}
1416
1417		if (n >= nr_probe)
1418			break;
1419	}
1420
1421	if (left)
1422		return n;
1423	else
1424		return -ENODEV;
1425}
1426
1427/**
1428 * early_platform_driver_probe - probe a class of registered drivers
1429 * @class_str: string to identify early platform driver class
1430 * @nr_probe: number of platform devices to successfully probe before exiting
1431 * @user_only: only probe user specified early platform devices
1432 *
1433 * Used by architecture code to probe registered early platform drivers
1434 * within a certain class. For probe to happen a registered early platform
1435 * device matching a registered early platform driver is needed.
1436 */
1437int __init early_platform_driver_probe(char *class_str,
1438				       int nr_probe,
1439				       int user_only)
1440{
1441	int k, n, i;
1442
1443	n = 0;
1444	for (i = -2; n < nr_probe; i++) {
1445		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1446
1447		if (k < 0)
1448			break;
1449
1450		n += k;
1451
1452		if (user_only)
1453			break;
1454	}
1455
1456	return n;
1457}
1458
1459/**
1460 * early_platform_cleanup - clean up early platform code
1461 */
1462void __init early_platform_cleanup(void)
1463{
1464	struct platform_device *pd, *pd2;
1465
1466	/* clean up the devres list used to chain devices */
1467	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1468				 dev.devres_head) {
1469		list_del(&pd->dev.devres_head);
1470		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1471	}
1472}
1473