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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
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * platform.c - platform 'pseudo' bus for legacy devices
   4 *
   5 * Copyright (c) 2002-3 Patrick Mochel
   6 * Copyright (c) 2002-3 Open Source Development Labs
   7 *
   8 * Please see Documentation/driver-api/driver-model/platform.rst for more
 
 
   9 * information.
  10 */
  11
  12#include <linux/string.h>
  13#include <linux/platform_device.h>
  14#include <linux/of_device.h>
  15#include <linux/of_irq.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/dma-mapping.h>
  19#include <linux/memblock.h>
  20#include <linux/err.h>
  21#include <linux/slab.h>
  22#include <linux/pm_runtime.h>
  23#include <linux/pm_domain.h>
  24#include <linux/idr.h>
  25#include <linux/acpi.h>
  26#include <linux/clk/clk-conf.h>
  27#include <linux/limits.h>
  28#include <linux/property.h>
  29#include <linux/kmemleak.h>
  30
  31#include "base.h"
  32#include "power/power.h"
  33
  34/* For automatically allocated device IDs */
  35static DEFINE_IDA(platform_devid_ida);
  36
  37struct device platform_bus = {
  38	.init_name	= "platform",
  39};
  40EXPORT_SYMBOL_GPL(platform_bus);
  41
  42/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  43 * platform_get_resource - get a resource for a device
  44 * @dev: platform device
  45 * @type: resource type
  46 * @num: resource index
  47 */
  48struct resource *platform_get_resource(struct platform_device *dev,
  49				       unsigned int type, unsigned int num)
  50{
  51	int i;
  52
  53	for (i = 0; i < dev->num_resources; i++) {
  54		struct resource *r = &dev->resource[i];
  55
  56		if (type == resource_type(r) && num-- == 0)
  57			return r;
  58	}
  59	return NULL;
  60}
  61EXPORT_SYMBOL_GPL(platform_get_resource);
  62
  63/**
  64 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
  65 *				    device
  66 *
  67 * @pdev: platform device to use both for memory resource lookup as well as
  68 *        resource management
  69 * @index: resource index
  70 */
  71#ifdef CONFIG_HAS_IOMEM
  72void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
  73					     unsigned int index)
  74{
  75	struct resource *res;
  76
  77	res = platform_get_resource(pdev, IORESOURCE_MEM, index);
  78	return devm_ioremap_resource(&pdev->dev, res);
  79}
  80EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
  81#endif /* CONFIG_HAS_IOMEM */
  82
  83static int __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		int ret;
  94
  95		ret = of_irq_get(dev->dev.of_node, num);
  96		if (ret > 0 || ret == -EPROBE_DEFER)
  97			return ret;
  98	}
  99
 100	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
 101	if (has_acpi_companion(&dev->dev)) {
 102		if (r && r->flags & IORESOURCE_DISABLED) {
 103			int ret;
 104
 105			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
 106			if (ret)
 107				return ret;
 108		}
 109	}
 110
 111	/*
 112	 * The resources may pass trigger flags to the irqs that need
 113	 * to be set up. It so happens that the trigger flags for
 114	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
 115	 * settings.
 116	 */
 117	if (r && r->flags & IORESOURCE_BITS) {
 118		struct irq_data *irqd;
 119
 120		irqd = irq_get_irq_data(r->start);
 121		if (!irqd)
 122			return -ENXIO;
 123		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
 124	}
 125
 126	if (r)
 127		return r->start;
 128
 129	/*
 130	 * For the index 0 interrupt, allow falling back to GpioInt
 131	 * resources. While a device could have both Interrupt and GpioInt
 132	 * resources, making this fallback ambiguous, in many common cases
 133	 * the device will only expose one IRQ, and this fallback
 134	 * allows a common code path across either kind of resource.
 135	 */
 136	if (num == 0 && has_acpi_companion(&dev->dev)) {
 137		int ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
 138
 139		/* Our callers expect -ENXIO for missing IRQs. */
 140		if (ret >= 0 || ret == -EPROBE_DEFER)
 141			return ret;
 142	}
 143
 144	return -ENXIO;
 145#endif
 146}
 147
 148/**
 149 * platform_get_irq - get an IRQ for a device
 150 * @dev: platform device
 151 * @num: IRQ number index
 152 *
 153 * Gets an IRQ for a platform device and prints an error message if finding the
 154 * IRQ fails. Device drivers should check the return value for errors so as to
 155 * not pass a negative integer value to the request_irq() APIs.
 156 *
 157 * Example:
 158 *		int irq = platform_get_irq(pdev, 0);
 159 *		if (irq < 0)
 160 *			return irq;
 161 *
 162 * Return: IRQ number on success, negative error number on failure.
 163 */
 164int platform_get_irq(struct platform_device *dev, unsigned int num)
 165{
 166	int ret;
 167
 168	ret = __platform_get_irq(dev, num);
 169	if (ret < 0 && ret != -EPROBE_DEFER)
 170		dev_err(&dev->dev, "IRQ index %u not found\n", num);
 171
 172	return ret;
 173}
 174EXPORT_SYMBOL_GPL(platform_get_irq);
 175
 176/**
 177 * platform_get_irq_optional - get an optional IRQ for a device
 178 * @dev: platform device
 179 * @num: IRQ number index
 180 *
 181 * Gets an IRQ for a platform device. Device drivers should check the return
 182 * value for errors so as to not pass a negative integer value to the
 183 * request_irq() APIs. This is the same as platform_get_irq(), except that it
 184 * does not print an error message if an IRQ can not be obtained.
 185 *
 186 * Example:
 187 *		int irq = platform_get_irq_optional(pdev, 0);
 188 *		if (irq < 0)
 189 *			return irq;
 190 *
 191 * Return: IRQ number on success, negative error number on failure.
 192 */
 193int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
 194{
 195	return __platform_get_irq(dev, num);
 196}
 197EXPORT_SYMBOL_GPL(platform_get_irq_optional);
 198
 199/**
 200 * platform_irq_count - Count the number of IRQs a platform device uses
 201 * @dev: platform device
 202 *
 203 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
 204 */
 205int platform_irq_count(struct platform_device *dev)
 206{
 207	int ret, nr = 0;
 208
 209	while ((ret = __platform_get_irq(dev, nr)) >= 0)
 210		nr++;
 211
 212	if (ret == -EPROBE_DEFER)
 213		return ret;
 214
 215	return nr;
 216}
 217EXPORT_SYMBOL_GPL(platform_irq_count);
 218
 219/**
 220 * platform_get_resource_byname - get a resource for a device by name
 221 * @dev: platform device
 222 * @type: resource type
 223 * @name: resource name
 224 */
 225struct resource *platform_get_resource_byname(struct platform_device *dev,
 226					      unsigned int type,
 227					      const char *name)
 228{
 229	int i;
 230
 231	for (i = 0; i < dev->num_resources; i++) {
 232		struct resource *r = &dev->resource[i];
 233
 234		if (unlikely(!r->name))
 235			continue;
 236
 237		if (type == resource_type(r) && !strcmp(r->name, name))
 238			return r;
 239	}
 240	return NULL;
 241}
 242EXPORT_SYMBOL_GPL(platform_get_resource_byname);
 243
 244static int __platform_get_irq_byname(struct platform_device *dev,
 245				     const char *name)
 246{
 247	struct resource *r;
 248
 249	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
 250		int ret;
 251
 252		ret = of_irq_get_byname(dev->dev.of_node, name);
 253		if (ret > 0 || ret == -EPROBE_DEFER)
 254			return ret;
 255	}
 256
 257	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
 258	if (r)
 259		return r->start;
 260
 261	return -ENXIO;
 262}
 263
 264/**
 265 * platform_get_irq_byname - get an IRQ for a device by name
 266 * @dev: platform device
 267 * @name: IRQ name
 268 *
 269 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
 270 *
 271 * Return: IRQ number on success, negative error number on failure.
 272 */
 273int platform_get_irq_byname(struct platform_device *dev, const char *name)
 274{
 275	int ret;
 
 276
 277	ret = __platform_get_irq_byname(dev, name);
 278	if (ret < 0 && ret != -EPROBE_DEFER)
 279		dev_err(&dev->dev, "IRQ %s not found\n", name);
 280
 281	return ret;
 282}
 283EXPORT_SYMBOL_GPL(platform_get_irq_byname);
 284
 285/**
 286 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
 287 * @dev: platform device
 288 * @name: IRQ name
 289 *
 290 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
 291 * does not print an error message if an IRQ can not be obtained.
 292 *
 293 * Return: IRQ number on success, negative error number on failure.
 294 */
 295int platform_get_irq_byname_optional(struct platform_device *dev,
 296				     const char *name)
 297{
 298	return __platform_get_irq_byname(dev, name);
 299}
 300EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
 301
 302/**
 303 * platform_add_devices - add a numbers of platform devices
 304 * @devs: array of platform devices to add
 305 * @num: number of platform devices in array
 306 */
 307int platform_add_devices(struct platform_device **devs, int num)
 308{
 309	int i, ret = 0;
 310
 311	for (i = 0; i < num; i++) {
 312		ret = platform_device_register(devs[i]);
 313		if (ret) {
 314			while (--i >= 0)
 315				platform_device_unregister(devs[i]);
 316			break;
 317		}
 318	}
 319
 320	return ret;
 321}
 322EXPORT_SYMBOL_GPL(platform_add_devices);
 323
 324struct platform_object {
 325	struct platform_device pdev;
 326	char name[];
 327};
 328
 329/*
 330 * Set up default DMA mask for platform devices if the they weren't
 331 * previously set by the architecture / DT.
 332 */
 333static void setup_pdev_dma_masks(struct platform_device *pdev)
 334{
 335	if (!pdev->dev.coherent_dma_mask)
 336		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 337	if (!pdev->dma_mask)
 338		pdev->dma_mask = DMA_BIT_MASK(32);
 339	if (!pdev->dev.dma_mask)
 340		pdev->dev.dma_mask = &pdev->dma_mask;
 341};
 342
 343/**
 344 * platform_device_put - destroy a platform device
 345 * @pdev: platform device to free
 346 *
 347 * Free all memory associated with a platform device.  This function must
 348 * _only_ be externally called in error cases.  All other usage is a bug.
 349 */
 350void platform_device_put(struct platform_device *pdev)
 351{
 352	if (!IS_ERR_OR_NULL(pdev))
 353		put_device(&pdev->dev);
 354}
 355EXPORT_SYMBOL_GPL(platform_device_put);
 356
 357static void platform_device_release(struct device *dev)
 358{
 359	struct platform_object *pa = container_of(dev, struct platform_object,
 360						  pdev.dev);
 361
 362	of_device_node_put(&pa->pdev.dev);
 363	kfree(pa->pdev.dev.platform_data);
 364	kfree(pa->pdev.mfd_cell);
 365	kfree(pa->pdev.resource);
 366	kfree(pa->pdev.driver_override);
 367	kfree(pa);
 368}
 369
 370/**
 371 * platform_device_alloc - create a platform device
 372 * @name: base name of the device we're adding
 373 * @id: instance id
 374 *
 375 * Create a platform device object which can have other objects attached
 376 * to it, and which will have attached objects freed when it is released.
 377 */
 378struct platform_device *platform_device_alloc(const char *name, int id)
 379{
 380	struct platform_object *pa;
 381
 382	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
 383	if (pa) {
 384		strcpy(pa->name, name);
 385		pa->pdev.name = pa->name;
 386		pa->pdev.id = id;
 387		device_initialize(&pa->pdev.dev);
 388		pa->pdev.dev.release = platform_device_release;
 389		setup_pdev_dma_masks(&pa->pdev);
 390	}
 391
 392	return pa ? &pa->pdev : NULL;
 393}
 394EXPORT_SYMBOL_GPL(platform_device_alloc);
 395
 396/**
 397 * platform_device_add_resources - add resources to a platform device
 398 * @pdev: platform device allocated by platform_device_alloc to add resources to
 399 * @res: set of resources that needs to be allocated for the device
 400 * @num: number of resources
 401 *
 402 * Add a copy of the resources to the platform device.  The memory
 403 * associated with the resources will be freed when the platform device is
 404 * released.
 405 */
 406int platform_device_add_resources(struct platform_device *pdev,
 407				  const struct resource *res, unsigned int num)
 408{
 409	struct resource *r = NULL;
 410
 411	if (res) {
 412		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
 413		if (!r)
 414			return -ENOMEM;
 415	}
 416
 417	kfree(pdev->resource);
 418	pdev->resource = r;
 419	pdev->num_resources = num;
 420	return 0;
 421}
 422EXPORT_SYMBOL_GPL(platform_device_add_resources);
 423
 424/**
 425 * platform_device_add_data - add platform-specific data to a platform device
 426 * @pdev: platform device allocated by platform_device_alloc to add resources to
 427 * @data: platform specific data for this platform device
 428 * @size: size of platform specific data
 429 *
 430 * Add a copy of platform specific data to the platform device's
 431 * platform_data pointer.  The memory associated with the platform data
 432 * will be freed when the platform device is released.
 433 */
 434int platform_device_add_data(struct platform_device *pdev, const void *data,
 435			     size_t size)
 436{
 437	void *d = NULL;
 438
 439	if (data) {
 440		d = kmemdup(data, size, GFP_KERNEL);
 441		if (!d)
 442			return -ENOMEM;
 443	}
 444
 445	kfree(pdev->dev.platform_data);
 446	pdev->dev.platform_data = d;
 447	return 0;
 448}
 449EXPORT_SYMBOL_GPL(platform_device_add_data);
 450
 451/**
 452 * platform_device_add_properties - add built-in properties to a platform device
 453 * @pdev: platform device to add properties to
 454 * @properties: null terminated array of properties to add
 455 *
 456 * The function will take deep copy of @properties and attach the copy to the
 457 * platform device. The memory associated with properties will be freed when the
 458 * platform device is released.
 459 */
 460int platform_device_add_properties(struct platform_device *pdev,
 461				   const struct property_entry *properties)
 462{
 463	return device_add_properties(&pdev->dev, properties);
 464}
 465EXPORT_SYMBOL_GPL(platform_device_add_properties);
 466
 467/**
 468 * platform_device_add - add a platform device to device hierarchy
 469 * @pdev: platform device we're adding
 470 *
 471 * This is part 2 of platform_device_register(), though may be called
 472 * separately _iff_ pdev was allocated by platform_device_alloc().
 473 */
 474int platform_device_add(struct platform_device *pdev)
 475{
 476	int i, ret;
 477
 478	if (!pdev)
 479		return -EINVAL;
 480
 481	if (!pdev->dev.parent)
 482		pdev->dev.parent = &platform_bus;
 483
 484	pdev->dev.bus = &platform_bus_type;
 485
 486	switch (pdev->id) {
 487	default:
 488		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
 489		break;
 490	case PLATFORM_DEVID_NONE:
 491		dev_set_name(&pdev->dev, "%s", pdev->name);
 492		break;
 493	case PLATFORM_DEVID_AUTO:
 494		/*
 495		 * Automatically allocated device ID. We mark it as such so
 496		 * that we remember it must be freed, and we append a suffix
 497		 * to avoid namespace collision with explicit IDs.
 498		 */
 499		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
 500		if (ret < 0)
 501			goto err_out;
 502		pdev->id = ret;
 503		pdev->id_auto = true;
 504		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
 505		break;
 506	}
 507
 508	for (i = 0; i < pdev->num_resources; i++) {
 509		struct resource *p, *r = &pdev->resource[i];
 510
 511		if (r->name == NULL)
 512			r->name = dev_name(&pdev->dev);
 513
 514		p = r->parent;
 515		if (!p) {
 516			if (resource_type(r) == IORESOURCE_MEM)
 517				p = &iomem_resource;
 518			else if (resource_type(r) == IORESOURCE_IO)
 519				p = &ioport_resource;
 520		}
 521
 522		if (p) {
 523			ret = insert_resource(p, r);
 524			if (ret) {
 525				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
 526				goto failed;
 527			}
 528		}
 529	}
 530
 531	pr_debug("Registering platform device '%s'. Parent at %s\n",
 532		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
 533
 534	ret = device_add(&pdev->dev);
 535	if (ret == 0)
 536		return ret;
 537
 538 failed:
 539	if (pdev->id_auto) {
 540		ida_simple_remove(&platform_devid_ida, pdev->id);
 541		pdev->id = PLATFORM_DEVID_AUTO;
 542	}
 543
 544	while (--i >= 0) {
 545		struct resource *r = &pdev->resource[i];
 546		if (r->parent)
 
 
 547			release_resource(r);
 548	}
 549
 550 err_out:
 551	return ret;
 552}
 553EXPORT_SYMBOL_GPL(platform_device_add);
 554
 555/**
 556 * platform_device_del - remove a platform-level device
 557 * @pdev: platform device we're removing
 558 *
 559 * Note that this function will also release all memory- and port-based
 560 * resources owned by the device (@dev->resource).  This function must
 561 * _only_ be externally called in error cases.  All other usage is a bug.
 562 */
 563void platform_device_del(struct platform_device *pdev)
 564{
 565	int i;
 566
 567	if (!IS_ERR_OR_NULL(pdev)) {
 568		device_del(&pdev->dev);
 569
 570		if (pdev->id_auto) {
 571			ida_simple_remove(&platform_devid_ida, pdev->id);
 572			pdev->id = PLATFORM_DEVID_AUTO;
 573		}
 574
 575		for (i = 0; i < pdev->num_resources; i++) {
 576			struct resource *r = &pdev->resource[i];
 577			if (r->parent)
 
 
 578				release_resource(r);
 579		}
 580	}
 581}
 582EXPORT_SYMBOL_GPL(platform_device_del);
 583
 584/**
 585 * platform_device_register - add a platform-level device
 586 * @pdev: platform device we're adding
 587 */
 588int platform_device_register(struct platform_device *pdev)
 589{
 590	device_initialize(&pdev->dev);
 591	setup_pdev_dma_masks(pdev);
 592	return platform_device_add(pdev);
 593}
 594EXPORT_SYMBOL_GPL(platform_device_register);
 595
 596/**
 597 * platform_device_unregister - unregister a platform-level device
 598 * @pdev: platform device we're unregistering
 599 *
 600 * Unregistration is done in 2 steps. First we release all resources
 601 * and remove it from the subsystem, then we drop reference count by
 602 * calling platform_device_put().
 603 */
 604void platform_device_unregister(struct platform_device *pdev)
 605{
 606	platform_device_del(pdev);
 607	platform_device_put(pdev);
 608}
 609EXPORT_SYMBOL_GPL(platform_device_unregister);
 610
 611/**
 612 * platform_device_register_full - add a platform-level device with
 613 * resources and platform-specific data
 614 *
 615 * @pdevinfo: data used to create device
 
 
 
 
 
 
 616 *
 617 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 618 */
 619struct platform_device *platform_device_register_full(
 620		const struct platform_device_info *pdevinfo)
 
 
 
 621{
 622	int ret = -ENOMEM;
 623	struct platform_device *pdev;
 624
 625	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
 626	if (!pdev)
 627		return ERR_PTR(-ENOMEM);
 628
 629	pdev->dev.parent = pdevinfo->parent;
 630	pdev->dev.fwnode = pdevinfo->fwnode;
 631	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
 632	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
 633
 634	if (pdevinfo->dma_mask) {
 635		/*
 636		 * This memory isn't freed when the device is put,
 637		 * I don't have a nice idea for that though.  Conceptually
 638		 * dma_mask in struct device should not be a pointer.
 639		 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
 640		 */
 641		pdev->dev.dma_mask =
 642			kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
 643		if (!pdev->dev.dma_mask)
 644			goto err;
 645
 646		kmemleak_ignore(pdev->dev.dma_mask);
 647
 648		*pdev->dev.dma_mask = pdevinfo->dma_mask;
 649		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
 650	}
 651
 652	ret = platform_device_add_resources(pdev,
 653			pdevinfo->res, pdevinfo->num_res);
 654	if (ret)
 655		goto err;
 656
 657	ret = platform_device_add_data(pdev,
 658			pdevinfo->data, pdevinfo->size_data);
 659	if (ret)
 660		goto err;
 661
 662	if (pdevinfo->properties) {
 663		ret = platform_device_add_properties(pdev,
 664						     pdevinfo->properties);
 665		if (ret)
 666			goto err;
 667	}
 668
 669	ret = platform_device_add(pdev);
 670	if (ret) {
 671err:
 672		ACPI_COMPANION_SET(&pdev->dev, NULL);
 673		kfree(pdev->dev.dma_mask);
 674		platform_device_put(pdev);
 675		return ERR_PTR(ret);
 676	}
 677
 678	return pdev;
 679}
 680EXPORT_SYMBOL_GPL(platform_device_register_full);
 681
 682static int platform_drv_probe(struct device *_dev)
 683{
 684	struct platform_driver *drv = to_platform_driver(_dev->driver);
 685	struct platform_device *dev = to_platform_device(_dev);
 686	int ret;
 687
 688	ret = of_clk_set_defaults(_dev->of_node, false);
 689	if (ret < 0)
 690		return ret;
 691
 692	ret = dev_pm_domain_attach(_dev, true);
 693	if (ret)
 694		goto out;
 695
 696	if (drv->probe) {
 697		ret = drv->probe(dev);
 698		if (ret)
 699			dev_pm_domain_detach(_dev, true);
 700	}
 701
 702out:
 703	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 704		dev_warn(_dev, "probe deferral not supported\n");
 705		ret = -ENXIO;
 706	}
 707
 708	return ret;
 709}
 710
 711static int platform_drv_probe_fail(struct device *_dev)
 712{
 713	return -ENXIO;
 714}
 715
 716static int platform_drv_remove(struct device *_dev)
 717{
 718	struct platform_driver *drv = to_platform_driver(_dev->driver);
 719	struct platform_device *dev = to_platform_device(_dev);
 720	int ret = 0;
 721
 722	if (drv->remove)
 723		ret = drv->remove(dev);
 724	dev_pm_domain_detach(_dev, true);
 725
 726	return ret;
 727}
 728
 729static void platform_drv_shutdown(struct device *_dev)
 730{
 731	struct platform_driver *drv = to_platform_driver(_dev->driver);
 732	struct platform_device *dev = to_platform_device(_dev);
 733
 734	if (drv->shutdown)
 735		drv->shutdown(dev);
 736}
 737
 738/**
 739 * __platform_driver_register - register a driver for platform-level devices
 740 * @drv: platform driver structure
 741 * @owner: owning module/driver
 742 */
 743int __platform_driver_register(struct platform_driver *drv,
 744				struct module *owner)
 745{
 746	drv->driver.owner = owner;
 747	drv->driver.bus = &platform_bus_type;
 748	drv->driver.probe = platform_drv_probe;
 749	drv->driver.remove = platform_drv_remove;
 750	drv->driver.shutdown = platform_drv_shutdown;
 
 
 
 751
 752	return driver_register(&drv->driver);
 753}
 754EXPORT_SYMBOL_GPL(__platform_driver_register);
 755
 756/**
 757 * platform_driver_unregister - unregister a driver for platform-level devices
 758 * @drv: platform driver structure
 759 */
 760void platform_driver_unregister(struct platform_driver *drv)
 761{
 762	driver_unregister(&drv->driver);
 763}
 764EXPORT_SYMBOL_GPL(platform_driver_unregister);
 765
 766/**
 767 * __platform_driver_probe - register driver for non-hotpluggable device
 768 * @drv: platform driver structure
 769 * @probe: the driver probe routine, probably from an __init section
 770 * @module: module which will be the owner of the driver
 771 *
 772 * Use this instead of platform_driver_register() when you know the device
 773 * is not hotpluggable and has already been registered, and you want to
 774 * remove its run-once probe() infrastructure from memory after the driver
 775 * has bound to the device.
 776 *
 777 * One typical use for this would be with drivers for controllers integrated
 778 * into system-on-chip processors, where the controller devices have been
 779 * configured as part of board setup.
 780 *
 781 * Note that this is incompatible with deferred probing.
 782 *
 783 * Returns zero if the driver registered and bound to a device, else returns
 784 * a negative error code and with the driver not registered.
 785 */
 786int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 787		int (*probe)(struct platform_device *), struct module *module)
 788{
 789	int retval, code;
 790
 791	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
 792		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
 793			 drv->driver.name, __func__);
 794		return -EINVAL;
 795	}
 796
 797	/*
 798	 * We have to run our probes synchronously because we check if
 799	 * we find any devices to bind to and exit with error if there
 800	 * are any.
 801	 */
 802	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
 803
 804	/*
 805	 * Prevent driver from requesting probe deferral to avoid further
 806	 * futile probe attempts.
 807	 */
 808	drv->prevent_deferred_probe = true;
 809
 810	/* make sure driver won't have bind/unbind attributes */
 811	drv->driver.suppress_bind_attrs = true;
 812
 813	/* temporary section violation during probe() */
 814	drv->probe = probe;
 815	retval = code = __platform_driver_register(drv, module);
 816
 817	/*
 818	 * Fixup that section violation, being paranoid about code scanning
 819	 * the list of drivers in order to probe new devices.  Check to see
 820	 * if the probe was successful, and make sure any forced probes of
 821	 * new devices fail.
 822	 */
 823	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
 824	drv->probe = NULL;
 825	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 826		retval = -ENODEV;
 827	drv->driver.probe = platform_drv_probe_fail;
 828	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 829
 830	if (code != retval)
 831		platform_driver_unregister(drv);
 832	return retval;
 833}
 834EXPORT_SYMBOL_GPL(__platform_driver_probe);
 835
 836/**
 837 * __platform_create_bundle - register driver and create corresponding device
 838 * @driver: platform driver structure
 839 * @probe: the driver probe routine, probably from an __init section
 840 * @res: set of resources that needs to be allocated for the device
 841 * @n_res: number of resources
 842 * @data: platform specific data for this platform device
 843 * @size: size of platform specific data
 844 * @module: module which will be the owner of the driver
 845 *
 846 * Use this in legacy-style modules that probe hardware directly and
 847 * register a single platform device and corresponding platform driver.
 848 *
 849 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
 850 */
 851struct platform_device * __init_or_module __platform_create_bundle(
 852			struct platform_driver *driver,
 853			int (*probe)(struct platform_device *),
 854			struct resource *res, unsigned int n_res,
 855			const void *data, size_t size, struct module *module)
 856{
 857	struct platform_device *pdev;
 858	int error;
 859
 860	pdev = platform_device_alloc(driver->driver.name, -1);
 861	if (!pdev) {
 862		error = -ENOMEM;
 863		goto err_out;
 864	}
 865
 866	error = platform_device_add_resources(pdev, res, n_res);
 867	if (error)
 868		goto err_pdev_put;
 869
 870	error = platform_device_add_data(pdev, data, size);
 871	if (error)
 872		goto err_pdev_put;
 873
 874	error = platform_device_add(pdev);
 875	if (error)
 876		goto err_pdev_put;
 877
 878	error = __platform_driver_probe(driver, probe, module);
 879	if (error)
 880		goto err_pdev_del;
 881
 882	return pdev;
 883
 884err_pdev_del:
 885	platform_device_del(pdev);
 886err_pdev_put:
 887	platform_device_put(pdev);
 888err_out:
 889	return ERR_PTR(error);
 890}
 891EXPORT_SYMBOL_GPL(__platform_create_bundle);
 892
 893/**
 894 * __platform_register_drivers - register an array of platform drivers
 895 * @drivers: an array of drivers to register
 896 * @count: the number of drivers to register
 897 * @owner: module owning the drivers
 898 *
 899 * Registers platform drivers specified by an array. On failure to register a
 900 * driver, all previously registered drivers will be unregistered. Callers of
 901 * this API should use platform_unregister_drivers() to unregister drivers in
 902 * the reverse order.
 903 *
 904 * Returns: 0 on success or a negative error code on failure.
 905 */
 906int __platform_register_drivers(struct platform_driver * const *drivers,
 907				unsigned int count, struct module *owner)
 908{
 909	unsigned int i;
 910	int err;
 911
 912	for (i = 0; i < count; i++) {
 913		pr_debug("registering platform driver %ps\n", drivers[i]);
 914
 915		err = __platform_driver_register(drivers[i], owner);
 916		if (err < 0) {
 917			pr_err("failed to register platform driver %ps: %d\n",
 918			       drivers[i], err);
 919			goto error;
 920		}
 921	}
 922
 923	return 0;
 924
 925error:
 926	while (i--) {
 927		pr_debug("unregistering platform driver %ps\n", drivers[i]);
 928		platform_driver_unregister(drivers[i]);
 929	}
 930
 931	return err;
 932}
 933EXPORT_SYMBOL_GPL(__platform_register_drivers);
 934
 935/**
 936 * platform_unregister_drivers - unregister an array of platform drivers
 937 * @drivers: an array of drivers to unregister
 938 * @count: the number of drivers to unregister
 939 *
 940 * Unegisters platform drivers specified by an array. This is typically used
 941 * to complement an earlier call to platform_register_drivers(). Drivers are
 942 * unregistered in the reverse order in which they were registered.
 943 */
 944void platform_unregister_drivers(struct platform_driver * const *drivers,
 945				 unsigned int count)
 946{
 947	while (count--) {
 948		pr_debug("unregistering platform driver %ps\n", drivers[count]);
 949		platform_driver_unregister(drivers[count]);
 950	}
 951}
 952EXPORT_SYMBOL_GPL(platform_unregister_drivers);
 953
 954/* modalias support enables more hands-off userspace setup:
 955 * (a) environment variable lets new-style hotplug events work once system is
 956 *     fully running:  "modprobe $MODALIAS"
 957 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
 958 *     mishandled before system is fully running:  "modprobe $(cat modalias)"
 959 */
 960static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 961			     char *buf)
 962{
 963	struct platform_device	*pdev = to_platform_device(dev);
 964	int len;
 965
 966	len = of_device_modalias(dev, buf, PAGE_SIZE);
 967	if (len != -ENODEV)
 968		return len;
 969
 970	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
 971	if (len != -ENODEV)
 972		return len;
 973
 974	len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
 975
 976	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 977}
 978static DEVICE_ATTR_RO(modalias);
 979
 980static ssize_t driver_override_store(struct device *dev,
 981				     struct device_attribute *attr,
 982				     const char *buf, size_t count)
 983{
 984	struct platform_device *pdev = to_platform_device(dev);
 985	char *driver_override, *old, *cp;
 986
 987	/* We need to keep extra room for a newline */
 988	if (count >= (PAGE_SIZE - 1))
 989		return -EINVAL;
 990
 991	driver_override = kstrndup(buf, count, GFP_KERNEL);
 992	if (!driver_override)
 993		return -ENOMEM;
 994
 995	cp = strchr(driver_override, '\n');
 996	if (cp)
 997		*cp = '\0';
 998
 999	device_lock(dev);
1000	old = pdev->driver_override;
1001	if (strlen(driver_override)) {
1002		pdev->driver_override = driver_override;
1003	} else {
1004		kfree(driver_override);
1005		pdev->driver_override = NULL;
1006	}
1007	device_unlock(dev);
1008
1009	kfree(old);
1010
1011	return count;
1012}
1013
1014static ssize_t driver_override_show(struct device *dev,
1015				    struct device_attribute *attr, char *buf)
1016{
1017	struct platform_device *pdev = to_platform_device(dev);
1018	ssize_t len;
1019
1020	device_lock(dev);
1021	len = sprintf(buf, "%s\n", pdev->driver_override);
1022	device_unlock(dev);
1023	return len;
1024}
1025static DEVICE_ATTR_RW(driver_override);
1026
1027
1028static struct attribute *platform_dev_attrs[] = {
1029	&dev_attr_modalias.attr,
1030	&dev_attr_driver_override.attr,
1031	NULL,
1032};
1033ATTRIBUTE_GROUPS(platform_dev);
1034
1035static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1036{
1037	struct platform_device	*pdev = to_platform_device(dev);
1038	int rc;
1039
1040	/* Some devices have extra OF data and an OF-style MODALIAS */
1041	rc = of_device_uevent_modalias(dev, env);
1042	if (rc != -ENODEV)
1043		return rc;
1044
1045	rc = acpi_device_uevent_modalias(dev, env);
1046	if (rc != -ENODEV)
1047		return rc;
1048
1049	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1050			pdev->name);
1051	return 0;
1052}
1053
1054static const struct platform_device_id *platform_match_id(
1055			const struct platform_device_id *id,
1056			struct platform_device *pdev)
1057{
1058	while (id->name[0]) {
1059		if (strcmp(pdev->name, id->name) == 0) {
1060			pdev->id_entry = id;
1061			return id;
1062		}
1063		id++;
1064	}
1065	return NULL;
1066}
1067
1068/**
1069 * platform_match - bind platform device to platform driver.
1070 * @dev: device.
1071 * @drv: driver.
1072 *
1073 * Platform device IDs are assumed to be encoded like this:
1074 * "<name><instance>", where <name> is a short description of the type of
1075 * device, like "pci" or "floppy", and <instance> is the enumerated
1076 * instance of the device, like '0' or '42'.  Driver IDs are simply
1077 * "<name>".  So, extract the <name> from the platform_device structure,
1078 * and compare it against the name of the driver. Return whether they match
1079 * or not.
1080 */
1081static int platform_match(struct device *dev, struct device_driver *drv)
1082{
1083	struct platform_device *pdev = to_platform_device(dev);
1084	struct platform_driver *pdrv = to_platform_driver(drv);
1085
1086	/* When driver_override is set, only bind to the matching driver */
1087	if (pdev->driver_override)
1088		return !strcmp(pdev->driver_override, drv->name);
1089
1090	/* Attempt an OF style match first */
1091	if (of_driver_match_device(dev, drv))
1092		return 1;
1093
1094	/* Then try ACPI style match */
1095	if (acpi_driver_match_device(dev, drv))
1096		return 1;
1097
1098	/* Then try to match against the id table */
1099	if (pdrv->id_table)
1100		return platform_match_id(pdrv->id_table, pdev) != NULL;
1101
1102	/* fall-back to driver name match */
1103	return (strcmp(pdev->name, drv->name) == 0);
1104}
1105
1106#ifdef CONFIG_PM_SLEEP
1107
1108static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1109{
1110	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1111	struct platform_device *pdev = to_platform_device(dev);
1112	int ret = 0;
1113
1114	if (dev->driver && pdrv->suspend)
1115		ret = pdrv->suspend(pdev, mesg);
1116
1117	return ret;
1118}
1119
1120static int platform_legacy_resume(struct device *dev)
1121{
1122	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1123	struct platform_device *pdev = to_platform_device(dev);
1124	int ret = 0;
1125
1126	if (dev->driver && pdrv->resume)
1127		ret = pdrv->resume(pdev);
1128
1129	return ret;
1130}
1131
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1132#endif /* CONFIG_PM_SLEEP */
1133
1134#ifdef CONFIG_SUSPEND
1135
1136int platform_pm_suspend(struct device *dev)
1137{
1138	struct device_driver *drv = dev->driver;
1139	int ret = 0;
1140
1141	if (!drv)
1142		return 0;
1143
1144	if (drv->pm) {
1145		if (drv->pm->suspend)
1146			ret = drv->pm->suspend(dev);
1147	} else {
1148		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1149	}
1150
1151	return ret;
1152}
1153
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1154int platform_pm_resume(struct device *dev)
1155{
1156	struct device_driver *drv = dev->driver;
1157	int ret = 0;
1158
1159	if (!drv)
1160		return 0;
1161
1162	if (drv->pm) {
1163		if (drv->pm->resume)
1164			ret = drv->pm->resume(dev);
1165	} else {
1166		ret = platform_legacy_resume(dev);
1167	}
1168
1169	return ret;
1170}
1171
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1172#endif /* CONFIG_SUSPEND */
1173
1174#ifdef CONFIG_HIBERNATE_CALLBACKS
1175
1176int platform_pm_freeze(struct device *dev)
1177{
1178	struct device_driver *drv = dev->driver;
1179	int ret = 0;
1180
1181	if (!drv)
1182		return 0;
1183
1184	if (drv->pm) {
1185		if (drv->pm->freeze)
1186			ret = drv->pm->freeze(dev);
1187	} else {
1188		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1189	}
1190
1191	return ret;
1192}
1193
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1194int platform_pm_thaw(struct device *dev)
1195{
1196	struct device_driver *drv = dev->driver;
1197	int ret = 0;
1198
1199	if (!drv)
1200		return 0;
1201
1202	if (drv->pm) {
1203		if (drv->pm->thaw)
1204			ret = drv->pm->thaw(dev);
1205	} else {
1206		ret = platform_legacy_resume(dev);
1207	}
1208
1209	return ret;
1210}
1211
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1212int platform_pm_poweroff(struct device *dev)
1213{
1214	struct device_driver *drv = dev->driver;
1215	int ret = 0;
1216
1217	if (!drv)
1218		return 0;
1219
1220	if (drv->pm) {
1221		if (drv->pm->poweroff)
1222			ret = drv->pm->poweroff(dev);
1223	} else {
1224		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1225	}
1226
1227	return ret;
1228}
1229
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1230int platform_pm_restore(struct device *dev)
1231{
1232	struct device_driver *drv = dev->driver;
1233	int ret = 0;
1234
1235	if (!drv)
1236		return 0;
1237
1238	if (drv->pm) {
1239		if (drv->pm->restore)
1240			ret = drv->pm->restore(dev);
1241	} else {
1242		ret = platform_legacy_resume(dev);
1243	}
1244
1245	return ret;
1246}
1247
1248#endif /* CONFIG_HIBERNATE_CALLBACKS */
1249
1250int platform_dma_configure(struct device *dev)
1251{
1252	enum dev_dma_attr attr;
1253	int ret = 0;
1254
1255	if (dev->of_node) {
1256		ret = of_dma_configure(dev, dev->of_node, true);
1257	} else if (has_acpi_companion(dev)) {
1258		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1259		ret = acpi_dma_configure(dev, attr);
 
1260	}
1261
1262	return ret;
1263}
1264
 
 
1265static const struct dev_pm_ops platform_dev_pm_ops = {
1266	.runtime_suspend = pm_generic_runtime_suspend,
1267	.runtime_resume = pm_generic_runtime_resume,
 
1268	USE_PLATFORM_PM_SLEEP_OPS
1269};
1270
1271struct bus_type platform_bus_type = {
1272	.name		= "platform",
1273	.dev_groups	= platform_dev_groups,
1274	.match		= platform_match,
1275	.uevent		= platform_uevent,
1276	.dma_configure	= platform_dma_configure,
1277	.pm		= &platform_dev_pm_ops,
1278};
1279EXPORT_SYMBOL_GPL(platform_bus_type);
1280
1281/**
1282 * platform_find_device_by_driver - Find a platform device with a given
1283 * driver.
1284 * @start: The device to start the search from.
1285 * @drv: The device driver to look for.
1286 */
1287struct device *platform_find_device_by_driver(struct device *start,
1288					      const struct device_driver *drv)
1289{
1290	return bus_find_device(&platform_bus_type, start, drv,
1291			       (void *)platform_match);
1292}
1293EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1294
1295int __init platform_bus_init(void)
1296{
1297	int error;
1298
1299	early_platform_cleanup();
1300
1301	error = device_register(&platform_bus);
1302	if (error) {
1303		put_device(&platform_bus);
1304		return error;
1305	}
1306	error =  bus_register(&platform_bus_type);
1307	if (error)
1308		device_unregister(&platform_bus);
1309	of_platform_register_reconfig_notifier();
1310	return error;
1311}
1312
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1313static __initdata LIST_HEAD(early_platform_driver_list);
1314static __initdata LIST_HEAD(early_platform_device_list);
1315
1316/**
1317 * early_platform_driver_register - register early platform driver
1318 * @epdrv: early_platform driver structure
1319 * @buf: string passed from early_param()
1320 *
1321 * Helper function for early_platform_init() / early_platform_init_buffer()
1322 */
1323int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1324					  char *buf)
1325{
1326	char *tmp;
1327	int n;
1328
1329	/* Simply add the driver to the end of the global list.
1330	 * Drivers will by default be put on the list in compiled-in order.
1331	 */
1332	if (!epdrv->list.next) {
1333		INIT_LIST_HEAD(&epdrv->list);
1334		list_add_tail(&epdrv->list, &early_platform_driver_list);
1335	}
1336
1337	/* If the user has specified device then make sure the driver
1338	 * gets prioritized. The driver of the last device specified on
1339	 * command line will be put first on the list.
1340	 */
1341	n = strlen(epdrv->pdrv->driver.name);
1342	if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1343		list_move(&epdrv->list, &early_platform_driver_list);
1344
1345		/* Allow passing parameters after device name */
1346		if (buf[n] == '\0' || buf[n] == ',')
1347			epdrv->requested_id = -1;
1348		else {
1349			epdrv->requested_id = simple_strtoul(&buf[n + 1],
1350							     &tmp, 10);
1351
1352			if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1353				epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1354				n = 0;
1355			} else
1356				n += strcspn(&buf[n + 1], ",") + 1;
1357		}
1358
1359		if (buf[n] == ',')
1360			n++;
1361
1362		if (epdrv->bufsize) {
1363			memcpy(epdrv->buffer, &buf[n],
1364			       min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1365			epdrv->buffer[epdrv->bufsize - 1] = '\0';
1366		}
1367	}
1368
1369	return 0;
1370}
1371
1372/**
1373 * early_platform_add_devices - adds a number of early platform devices
1374 * @devs: array of early platform devices to add
1375 * @num: number of early platform devices in array
1376 *
1377 * Used by early architecture code to register early platform devices and
1378 * their platform data.
1379 */
1380void __init early_platform_add_devices(struct platform_device **devs, int num)
1381{
1382	struct device *dev;
1383	int i;
1384
1385	/* simply add the devices to list */
1386	for (i = 0; i < num; i++) {
1387		dev = &devs[i]->dev;
1388
1389		if (!dev->devres_head.next) {
1390			pm_runtime_early_init(dev);
1391			INIT_LIST_HEAD(&dev->devres_head);
1392			list_add_tail(&dev->devres_head,
1393				      &early_platform_device_list);
1394		}
1395	}
1396}
1397
1398/**
1399 * early_platform_driver_register_all - register early platform drivers
1400 * @class_str: string to identify early platform driver class
1401 *
1402 * Used by architecture code to register all early platform drivers
1403 * for a certain class. If omitted then only early platform drivers
1404 * with matching kernel command line class parameters will be registered.
1405 */
1406void __init early_platform_driver_register_all(char *class_str)
1407{
1408	/* The "class_str" parameter may or may not be present on the kernel
1409	 * command line. If it is present then there may be more than one
1410	 * matching parameter.
1411	 *
1412	 * Since we register our early platform drivers using early_param()
1413	 * we need to make sure that they also get registered in the case
1414	 * when the parameter is missing from the kernel command line.
1415	 *
1416	 * We use parse_early_options() to make sure the early_param() gets
1417	 * called at least once. The early_param() may be called more than
1418	 * once since the name of the preferred device may be specified on
1419	 * the kernel command line. early_platform_driver_register() handles
1420	 * this case for us.
1421	 */
1422	parse_early_options(class_str);
1423}
1424
1425/**
1426 * early_platform_match - find early platform device matching driver
1427 * @epdrv: early platform driver structure
1428 * @id: id to match against
1429 */
1430static struct platform_device * __init
1431early_platform_match(struct early_platform_driver *epdrv, int id)
1432{
1433	struct platform_device *pd;
1434
1435	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1436		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1437			if (pd->id == id)
1438				return pd;
1439
1440	return NULL;
1441}
1442
1443/**
1444 * early_platform_left - check if early platform driver has matching devices
1445 * @epdrv: early platform driver structure
1446 * @id: return true if id or above exists
1447 */
1448static int __init early_platform_left(struct early_platform_driver *epdrv,
1449				       int id)
1450{
1451	struct platform_device *pd;
1452
1453	list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1454		if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1455			if (pd->id >= id)
1456				return 1;
1457
1458	return 0;
1459}
1460
1461/**
1462 * early_platform_driver_probe_id - probe drivers matching class_str and id
1463 * @class_str: string to identify early platform driver class
1464 * @id: id to match against
1465 * @nr_probe: number of platform devices to successfully probe before exiting
1466 */
1467static int __init early_platform_driver_probe_id(char *class_str,
1468						 int id,
1469						 int nr_probe)
1470{
1471	struct early_platform_driver *epdrv;
1472	struct platform_device *match;
1473	int match_id;
1474	int n = 0;
1475	int left = 0;
1476
1477	list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1478		/* only use drivers matching our class_str */
1479		if (strcmp(class_str, epdrv->class_str))
1480			continue;
1481
1482		if (id == -2) {
1483			match_id = epdrv->requested_id;
1484			left = 1;
1485
1486		} else {
1487			match_id = id;
1488			left += early_platform_left(epdrv, id);
1489
1490			/* skip requested id */
1491			switch (epdrv->requested_id) {
1492			case EARLY_PLATFORM_ID_ERROR:
1493			case EARLY_PLATFORM_ID_UNSET:
1494				break;
1495			default:
1496				if (epdrv->requested_id == id)
1497					match_id = EARLY_PLATFORM_ID_UNSET;
1498			}
1499		}
1500
1501		switch (match_id) {
1502		case EARLY_PLATFORM_ID_ERROR:
1503			pr_warn("%s: unable to parse %s parameter\n",
1504				class_str, epdrv->pdrv->driver.name);
1505			/* fall-through */
1506		case EARLY_PLATFORM_ID_UNSET:
1507			match = NULL;
1508			break;
1509		default:
1510			match = early_platform_match(epdrv, match_id);
1511		}
1512
1513		if (match) {
1514			/*
1515			 * Set up a sensible init_name to enable
1516			 * dev_name() and others to be used before the
1517			 * rest of the driver core is initialized.
1518			 */
1519			if (!match->dev.init_name && slab_is_available()) {
1520				if (match->id != -1)
1521					match->dev.init_name =
1522						kasprintf(GFP_KERNEL, "%s.%d",
1523							  match->name,
1524							  match->id);
1525				else
1526					match->dev.init_name =
1527						kasprintf(GFP_KERNEL, "%s",
1528							  match->name);
1529
1530				if (!match->dev.init_name)
1531					return -ENOMEM;
1532			}
1533
1534			if (epdrv->pdrv->probe(match))
1535				pr_warn("%s: unable to probe %s early.\n",
1536					class_str, match->name);
1537			else
1538				n++;
1539		}
1540
1541		if (n >= nr_probe)
1542			break;
1543	}
1544
1545	if (left)
1546		return n;
1547	else
1548		return -ENODEV;
1549}
1550
1551/**
1552 * early_platform_driver_probe - probe a class of registered drivers
1553 * @class_str: string to identify early platform driver class
1554 * @nr_probe: number of platform devices to successfully probe before exiting
1555 * @user_only: only probe user specified early platform devices
1556 *
1557 * Used by architecture code to probe registered early platform drivers
1558 * within a certain class. For probe to happen a registered early platform
1559 * device matching a registered early platform driver is needed.
1560 */
1561int __init early_platform_driver_probe(char *class_str,
1562				       int nr_probe,
1563				       int user_only)
1564{
1565	int k, n, i;
1566
1567	n = 0;
1568	for (i = -2; n < nr_probe; i++) {
1569		k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1570
1571		if (k < 0)
1572			break;
1573
1574		n += k;
1575
1576		if (user_only)
1577			break;
1578	}
1579
1580	return n;
1581}
1582
1583/**
1584 * early_platform_cleanup - clean up early platform code
1585 */
1586void __init early_platform_cleanup(void)
1587{
1588	struct platform_device *pd, *pd2;
1589
1590	/* clean up the devres list used to chain devices */
1591	list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1592				 dev.devres_head) {
1593		list_del(&pd->dev.devres_head);
1594		memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1595	}
1596}
1597