xref: /openbmc/linux/drivers/base/platform.c (revision b627b4ed)
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/platform_device.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/bootmem.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 
21 #include "base.h"
22 
23 #define to_platform_driver(drv)	(container_of((drv), struct platform_driver, \
24 				 driver))
25 
26 struct device platform_bus = {
27 	.init_name	= "platform",
28 };
29 EXPORT_SYMBOL_GPL(platform_bus);
30 
31 /**
32  * platform_get_resource - get a resource for a device
33  * @dev: platform device
34  * @type: resource type
35  * @num: resource index
36  */
37 struct resource *platform_get_resource(struct platform_device *dev,
38 				       unsigned int type, unsigned int num)
39 {
40 	int i;
41 
42 	for (i = 0; i < dev->num_resources; i++) {
43 		struct resource *r = &dev->resource[i];
44 
45 		if (type == resource_type(r) && num-- == 0)
46 			return r;
47 	}
48 	return NULL;
49 }
50 EXPORT_SYMBOL_GPL(platform_get_resource);
51 
52 /**
53  * platform_get_irq - get an IRQ for a device
54  * @dev: platform device
55  * @num: IRQ number index
56  */
57 int platform_get_irq(struct platform_device *dev, unsigned int num)
58 {
59 	struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
60 
61 	return r ? r->start : -ENXIO;
62 }
63 EXPORT_SYMBOL_GPL(platform_get_irq);
64 
65 /**
66  * platform_get_resource_byname - get a resource for a device by name
67  * @dev: platform device
68  * @type: resource type
69  * @name: resource name
70  */
71 struct resource *platform_get_resource_byname(struct platform_device *dev,
72 					      unsigned int type, char *name)
73 {
74 	int i;
75 
76 	for (i = 0; i < dev->num_resources; i++) {
77 		struct resource *r = &dev->resource[i];
78 
79 		if (type == resource_type(r) && !strcmp(r->name, name))
80 			return r;
81 	}
82 	return NULL;
83 }
84 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
85 
86 /**
87  * platform_get_irq - get an IRQ for a device
88  * @dev: platform device
89  * @name: IRQ name
90  */
91 int platform_get_irq_byname(struct platform_device *dev, char *name)
92 {
93 	struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
94 							  name);
95 
96 	return r ? r->start : -ENXIO;
97 }
98 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
99 
100 /**
101  * platform_add_devices - add a numbers of platform devices
102  * @devs: array of platform devices to add
103  * @num: number of platform devices in array
104  */
105 int platform_add_devices(struct platform_device **devs, int num)
106 {
107 	int i, ret = 0;
108 
109 	for (i = 0; i < num; i++) {
110 		ret = platform_device_register(devs[i]);
111 		if (ret) {
112 			while (--i >= 0)
113 				platform_device_unregister(devs[i]);
114 			break;
115 		}
116 	}
117 
118 	return ret;
119 }
120 EXPORT_SYMBOL_GPL(platform_add_devices);
121 
122 struct platform_object {
123 	struct platform_device pdev;
124 	char name[1];
125 };
126 
127 /**
128  * platform_device_put
129  * @pdev: platform device to free
130  *
131  * Free all memory associated with a platform device.  This function must
132  * _only_ be externally called in error cases.  All other usage is a bug.
133  */
134 void platform_device_put(struct platform_device *pdev)
135 {
136 	if (pdev)
137 		put_device(&pdev->dev);
138 }
139 EXPORT_SYMBOL_GPL(platform_device_put);
140 
141 static void platform_device_release(struct device *dev)
142 {
143 	struct platform_object *pa = container_of(dev, struct platform_object,
144 						  pdev.dev);
145 
146 	kfree(pa->pdev.dev.platform_data);
147 	kfree(pa->pdev.resource);
148 	kfree(pa);
149 }
150 
151 /**
152  * platform_device_alloc
153  * @name: base name of the device we're adding
154  * @id: instance id
155  *
156  * Create a platform device object which can have other objects attached
157  * to it, and which will have attached objects freed when it is released.
158  */
159 struct platform_device *platform_device_alloc(const char *name, int id)
160 {
161 	struct platform_object *pa;
162 
163 	pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
164 	if (pa) {
165 		strcpy(pa->name, name);
166 		pa->pdev.name = pa->name;
167 		pa->pdev.id = id;
168 		device_initialize(&pa->pdev.dev);
169 		pa->pdev.dev.release = platform_device_release;
170 	}
171 
172 	return pa ? &pa->pdev : NULL;
173 }
174 EXPORT_SYMBOL_GPL(platform_device_alloc);
175 
176 /**
177  * platform_device_add_resources
178  * @pdev: platform device allocated by platform_device_alloc to add resources to
179  * @res: set of resources that needs to be allocated for the device
180  * @num: number of resources
181  *
182  * Add a copy of the resources to the platform device.  The memory
183  * associated with the resources will be freed when the platform device is
184  * released.
185  */
186 int platform_device_add_resources(struct platform_device *pdev,
187 				  struct resource *res, unsigned int num)
188 {
189 	struct resource *r;
190 
191 	r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL);
192 	if (r) {
193 		memcpy(r, res, sizeof(struct resource) * num);
194 		pdev->resource = r;
195 		pdev->num_resources = num;
196 	}
197 	return r ? 0 : -ENOMEM;
198 }
199 EXPORT_SYMBOL_GPL(platform_device_add_resources);
200 
201 /**
202  * platform_device_add_data
203  * @pdev: platform device allocated by platform_device_alloc to add resources to
204  * @data: platform specific data for this platform device
205  * @size: size of platform specific data
206  *
207  * Add a copy of platform specific data to the platform device's
208  * platform_data pointer.  The memory associated with the platform data
209  * will be freed when the platform device is released.
210  */
211 int platform_device_add_data(struct platform_device *pdev, const void *data,
212 			     size_t size)
213 {
214 	void *d;
215 
216 	d = kmalloc(size, GFP_KERNEL);
217 	if (d) {
218 		memcpy(d, data, size);
219 		pdev->dev.platform_data = d;
220 		pdev->platform_data = d;
221 	}
222 	return d ? 0 : -ENOMEM;
223 }
224 EXPORT_SYMBOL_GPL(platform_device_add_data);
225 
226 /**
227  * platform_device_add - add a platform device to device hierarchy
228  * @pdev: platform device we're adding
229  *
230  * This is part 2 of platform_device_register(), though may be called
231  * separately _iff_ pdev was allocated by platform_device_alloc().
232  */
233 int platform_device_add(struct platform_device *pdev)
234 {
235 	int i, ret = 0;
236 
237 	if (!pdev)
238 		return -EINVAL;
239 
240 	if (!pdev->dev.parent)
241 		pdev->dev.parent = &platform_bus;
242 
243 	pdev->dev.bus = &platform_bus_type;
244 
245 	if (pdev->id != -1)
246 		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
247 	else
248 		dev_set_name(&pdev->dev, pdev->name);
249 
250 	/* We will remove platform_data field from struct device
251 	* if all platform devices pass its platform specific data
252 	* from platform_device. The conversion is going to be a
253 	* long time, so we allow the two cases coexist to make
254 	* this kind of fix more easily*/
255 	if (pdev->platform_data && pdev->dev.platform_data) {
256 		printk(KERN_ERR
257 			       "%s: use which platform_data?\n",
258 			       dev_name(&pdev->dev));
259 	} else if (pdev->platform_data) {
260 		pdev->dev.platform_data = pdev->platform_data;
261 	} else if (pdev->dev.platform_data) {
262 		pdev->platform_data = pdev->dev.platform_data;
263 	}
264 
265 	for (i = 0; i < pdev->num_resources; i++) {
266 		struct resource *p, *r = &pdev->resource[i];
267 
268 		if (r->name == NULL)
269 			r->name = dev_name(&pdev->dev);
270 
271 		p = r->parent;
272 		if (!p) {
273 			if (resource_type(r) == IORESOURCE_MEM)
274 				p = &iomem_resource;
275 			else if (resource_type(r) == IORESOURCE_IO)
276 				p = &ioport_resource;
277 		}
278 
279 		if (p && insert_resource(p, r)) {
280 			printk(KERN_ERR
281 			       "%s: failed to claim resource %d\n",
282 			       dev_name(&pdev->dev), i);
283 			ret = -EBUSY;
284 			goto failed;
285 		}
286 	}
287 
288 	pr_debug("Registering platform device '%s'. Parent at %s\n",
289 		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
290 
291 	ret = device_add(&pdev->dev);
292 	if (ret == 0)
293 		return ret;
294 
295  failed:
296 	while (--i >= 0) {
297 		struct resource *r = &pdev->resource[i];
298 		unsigned long type = resource_type(r);
299 
300 		if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
301 			release_resource(r);
302 	}
303 
304 	return ret;
305 }
306 EXPORT_SYMBOL_GPL(platform_device_add);
307 
308 /**
309  * platform_device_del - remove a platform-level device
310  * @pdev: platform device we're removing
311  *
312  * Note that this function will also release all memory- and port-based
313  * resources owned by the device (@dev->resource).  This function must
314  * _only_ be externally called in error cases.  All other usage is a bug.
315  */
316 void platform_device_del(struct platform_device *pdev)
317 {
318 	int i;
319 
320 	if (pdev) {
321 		device_del(&pdev->dev);
322 
323 		for (i = 0; i < pdev->num_resources; i++) {
324 			struct resource *r = &pdev->resource[i];
325 			unsigned long type = resource_type(r);
326 
327 			if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
328 				release_resource(r);
329 		}
330 	}
331 }
332 EXPORT_SYMBOL_GPL(platform_device_del);
333 
334 /**
335  * platform_device_register - add a platform-level device
336  * @pdev: platform device we're adding
337  */
338 int platform_device_register(struct platform_device *pdev)
339 {
340 	device_initialize(&pdev->dev);
341 	return platform_device_add(pdev);
342 }
343 EXPORT_SYMBOL_GPL(platform_device_register);
344 
345 /**
346  * platform_device_unregister - unregister a platform-level device
347  * @pdev: platform device we're unregistering
348  *
349  * Unregistration is done in 2 steps. First we release all resources
350  * and remove it from the subsystem, then we drop reference count by
351  * calling platform_device_put().
352  */
353 void platform_device_unregister(struct platform_device *pdev)
354 {
355 	platform_device_del(pdev);
356 	platform_device_put(pdev);
357 }
358 EXPORT_SYMBOL_GPL(platform_device_unregister);
359 
360 /**
361  * platform_device_register_simple
362  * @name: base name of the device we're adding
363  * @id: instance id
364  * @res: set of resources that needs to be allocated for the device
365  * @num: number of resources
366  *
367  * This function creates a simple platform device that requires minimal
368  * resource and memory management. Canned release function freeing memory
369  * allocated for the device allows drivers using such devices to be
370  * unloaded without waiting for the last reference to the device to be
371  * dropped.
372  *
373  * This interface is primarily intended for use with legacy drivers which
374  * probe hardware directly.  Because such drivers create sysfs device nodes
375  * themselves, rather than letting system infrastructure handle such device
376  * enumeration tasks, they don't fully conform to the Linux driver model.
377  * In particular, when such drivers are built as modules, they can't be
378  * "hotplugged".
379  */
380 struct platform_device *platform_device_register_simple(const char *name,
381 							int id,
382 							struct resource *res,
383 							unsigned int num)
384 {
385 	struct platform_device *pdev;
386 	int retval;
387 
388 	pdev = platform_device_alloc(name, id);
389 	if (!pdev) {
390 		retval = -ENOMEM;
391 		goto error;
392 	}
393 
394 	if (num) {
395 		retval = platform_device_add_resources(pdev, res, num);
396 		if (retval)
397 			goto error;
398 	}
399 
400 	retval = platform_device_add(pdev);
401 	if (retval)
402 		goto error;
403 
404 	return pdev;
405 
406 error:
407 	platform_device_put(pdev);
408 	return ERR_PTR(retval);
409 }
410 EXPORT_SYMBOL_GPL(platform_device_register_simple);
411 
412 /**
413  * platform_device_register_data
414  * @parent: parent device for the device we're adding
415  * @name: base name of the device we're adding
416  * @id: instance id
417  * @data: platform specific data for this platform device
418  * @size: size of platform specific data
419  *
420  * This function creates a simple platform device that requires minimal
421  * resource and memory management. Canned release function freeing memory
422  * allocated for the device allows drivers using such devices to be
423  * unloaded without waiting for the last reference to the device to be
424  * dropped.
425  */
426 struct platform_device *platform_device_register_data(
427 		struct device *parent,
428 		const char *name, int id,
429 		const void *data, size_t size)
430 {
431 	struct platform_device *pdev;
432 	int retval;
433 
434 	pdev = platform_device_alloc(name, id);
435 	if (!pdev) {
436 		retval = -ENOMEM;
437 		goto error;
438 	}
439 
440 	pdev->dev.parent = parent;
441 
442 	if (size) {
443 		retval = platform_device_add_data(pdev, data, size);
444 		if (retval)
445 			goto error;
446 	}
447 
448 	retval = platform_device_add(pdev);
449 	if (retval)
450 		goto error;
451 
452 	return pdev;
453 
454 error:
455 	platform_device_put(pdev);
456 	return ERR_PTR(retval);
457 }
458 
459 static int platform_drv_probe(struct device *_dev)
460 {
461 	struct platform_driver *drv = to_platform_driver(_dev->driver);
462 	struct platform_device *dev = to_platform_device(_dev);
463 
464 	return drv->probe(dev);
465 }
466 
467 static int platform_drv_probe_fail(struct device *_dev)
468 {
469 	return -ENXIO;
470 }
471 
472 static int platform_drv_remove(struct device *_dev)
473 {
474 	struct platform_driver *drv = to_platform_driver(_dev->driver);
475 	struct platform_device *dev = to_platform_device(_dev);
476 
477 	return drv->remove(dev);
478 }
479 
480 static void platform_drv_shutdown(struct device *_dev)
481 {
482 	struct platform_driver *drv = to_platform_driver(_dev->driver);
483 	struct platform_device *dev = to_platform_device(_dev);
484 
485 	drv->shutdown(dev);
486 }
487 
488 static int platform_drv_suspend(struct device *_dev, pm_message_t state)
489 {
490 	struct platform_driver *drv = to_platform_driver(_dev->driver);
491 	struct platform_device *dev = to_platform_device(_dev);
492 
493 	return drv->suspend(dev, state);
494 }
495 
496 static int platform_drv_resume(struct device *_dev)
497 {
498 	struct platform_driver *drv = to_platform_driver(_dev->driver);
499 	struct platform_device *dev = to_platform_device(_dev);
500 
501 	return drv->resume(dev);
502 }
503 
504 /**
505  * platform_driver_register
506  * @drv: platform driver structure
507  */
508 int platform_driver_register(struct platform_driver *drv)
509 {
510 	drv->driver.bus = &platform_bus_type;
511 	if (drv->probe)
512 		drv->driver.probe = platform_drv_probe;
513 	if (drv->remove)
514 		drv->driver.remove = platform_drv_remove;
515 	if (drv->shutdown)
516 		drv->driver.shutdown = platform_drv_shutdown;
517 	if (drv->suspend)
518 		drv->driver.suspend = platform_drv_suspend;
519 	if (drv->resume)
520 		drv->driver.resume = platform_drv_resume;
521 	return driver_register(&drv->driver);
522 }
523 EXPORT_SYMBOL_GPL(platform_driver_register);
524 
525 /**
526  * platform_driver_unregister
527  * @drv: platform driver structure
528  */
529 void platform_driver_unregister(struct platform_driver *drv)
530 {
531 	driver_unregister(&drv->driver);
532 }
533 EXPORT_SYMBOL_GPL(platform_driver_unregister);
534 
535 /**
536  * platform_driver_probe - register driver for non-hotpluggable device
537  * @drv: platform driver structure
538  * @probe: the driver probe routine, probably from an __init section
539  *
540  * Use this instead of platform_driver_register() when you know the device
541  * is not hotpluggable and has already been registered, and you want to
542  * remove its run-once probe() infrastructure from memory after the driver
543  * has bound to the device.
544  *
545  * One typical use for this would be with drivers for controllers integrated
546  * into system-on-chip processors, where the controller devices have been
547  * configured as part of board setup.
548  *
549  * Returns zero if the driver registered and bound to a device, else returns
550  * a negative error code and with the driver not registered.
551  */
552 int __init_or_module platform_driver_probe(struct platform_driver *drv,
553 		int (*probe)(struct platform_device *))
554 {
555 	int retval, code;
556 
557 	/* temporary section violation during probe() */
558 	drv->probe = probe;
559 	retval = code = platform_driver_register(drv);
560 
561 	/* Fixup that section violation, being paranoid about code scanning
562 	 * the list of drivers in order to probe new devices.  Check to see
563 	 * if the probe was successful, and make sure any forced probes of
564 	 * new devices fail.
565 	 */
566 	spin_lock(&platform_bus_type.p->klist_drivers.k_lock);
567 	drv->probe = NULL;
568 	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
569 		retval = -ENODEV;
570 	drv->driver.probe = platform_drv_probe_fail;
571 	spin_unlock(&platform_bus_type.p->klist_drivers.k_lock);
572 
573 	if (code != retval)
574 		platform_driver_unregister(drv);
575 	return retval;
576 }
577 EXPORT_SYMBOL_GPL(platform_driver_probe);
578 
579 /* modalias support enables more hands-off userspace setup:
580  * (a) environment variable lets new-style hotplug events work once system is
581  *     fully running:  "modprobe $MODALIAS"
582  * (b) sysfs attribute lets new-style coldplug recover from hotplug events
583  *     mishandled before system is fully running:  "modprobe $(cat modalias)"
584  */
585 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
586 			     char *buf)
587 {
588 	struct platform_device	*pdev = to_platform_device(dev);
589 	int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
590 
591 	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
592 }
593 
594 static struct device_attribute platform_dev_attrs[] = {
595 	__ATTR_RO(modalias),
596 	__ATTR_NULL,
597 };
598 
599 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
600 {
601 	struct platform_device	*pdev = to_platform_device(dev);
602 
603 	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
604 		(pdev->id_entry) ? pdev->id_entry->name : pdev->name);
605 	return 0;
606 }
607 
608 static const struct platform_device_id *platform_match_id(
609 			struct platform_device_id *id,
610 			struct platform_device *pdev)
611 {
612 	while (id->name[0]) {
613 		if (strcmp(pdev->name, id->name) == 0) {
614 			pdev->id_entry = id;
615 			return id;
616 		}
617 		id++;
618 	}
619 	return NULL;
620 }
621 
622 /**
623  * platform_match - bind platform device to platform driver.
624  * @dev: device.
625  * @drv: driver.
626  *
627  * Platform device IDs are assumed to be encoded like this:
628  * "<name><instance>", where <name> is a short description of the type of
629  * device, like "pci" or "floppy", and <instance> is the enumerated
630  * instance of the device, like '0' or '42'.  Driver IDs are simply
631  * "<name>".  So, extract the <name> from the platform_device structure,
632  * and compare it against the name of the driver. Return whether they match
633  * or not.
634  */
635 static int platform_match(struct device *dev, struct device_driver *drv)
636 {
637 	struct platform_device *pdev = to_platform_device(dev);
638 	struct platform_driver *pdrv = to_platform_driver(drv);
639 
640 	/* match against the id table first */
641 	if (pdrv->id_table)
642 		return platform_match_id(pdrv->id_table, pdev) != NULL;
643 
644 	/* fall-back to driver name match */
645 	return (strcmp(pdev->name, drv->name) == 0);
646 }
647 
648 #ifdef CONFIG_PM_SLEEP
649 
650 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
651 {
652 	int ret = 0;
653 
654 	if (dev->driver && dev->driver->suspend)
655 		ret = dev->driver->suspend(dev, mesg);
656 
657 	return ret;
658 }
659 
660 static int platform_legacy_suspend_late(struct device *dev, pm_message_t mesg)
661 {
662 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
663 	struct platform_device *pdev = to_platform_device(dev);
664 	int ret = 0;
665 
666 	if (dev->driver && pdrv->suspend_late)
667 		ret = pdrv->suspend_late(pdev, mesg);
668 
669 	return ret;
670 }
671 
672 static int platform_legacy_resume_early(struct device *dev)
673 {
674 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
675 	struct platform_device *pdev = to_platform_device(dev);
676 	int ret = 0;
677 
678 	if (dev->driver && pdrv->resume_early)
679 		ret = pdrv->resume_early(pdev);
680 
681 	return ret;
682 }
683 
684 static int platform_legacy_resume(struct device *dev)
685 {
686 	int ret = 0;
687 
688 	if (dev->driver && dev->driver->resume)
689 		ret = dev->driver->resume(dev);
690 
691 	return ret;
692 }
693 
694 static int platform_pm_prepare(struct device *dev)
695 {
696 	struct device_driver *drv = dev->driver;
697 	int ret = 0;
698 
699 	if (drv && drv->pm && drv->pm->prepare)
700 		ret = drv->pm->prepare(dev);
701 
702 	return ret;
703 }
704 
705 static void platform_pm_complete(struct device *dev)
706 {
707 	struct device_driver *drv = dev->driver;
708 
709 	if (drv && drv->pm && drv->pm->complete)
710 		drv->pm->complete(dev);
711 }
712 
713 #ifdef CONFIG_SUSPEND
714 
715 static int platform_pm_suspend(struct device *dev)
716 {
717 	struct device_driver *drv = dev->driver;
718 	int ret = 0;
719 
720 	if (!drv)
721 		return 0;
722 
723 	if (drv->pm) {
724 		if (drv->pm->suspend)
725 			ret = drv->pm->suspend(dev);
726 	} else {
727 		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
728 	}
729 
730 	return ret;
731 }
732 
733 static int platform_pm_suspend_noirq(struct device *dev)
734 {
735 	struct device_driver *drv = dev->driver;
736 	int ret = 0;
737 
738 	if (!drv)
739 		return 0;
740 
741 	if (drv->pm) {
742 		if (drv->pm->suspend_noirq)
743 			ret = drv->pm->suspend_noirq(dev);
744 	} else {
745 		ret = platform_legacy_suspend_late(dev, PMSG_SUSPEND);
746 	}
747 
748 	return ret;
749 }
750 
751 static int platform_pm_resume(struct device *dev)
752 {
753 	struct device_driver *drv = dev->driver;
754 	int ret = 0;
755 
756 	if (!drv)
757 		return 0;
758 
759 	if (drv->pm) {
760 		if (drv->pm->resume)
761 			ret = drv->pm->resume(dev);
762 	} else {
763 		ret = platform_legacy_resume(dev);
764 	}
765 
766 	return ret;
767 }
768 
769 static int platform_pm_resume_noirq(struct device *dev)
770 {
771 	struct device_driver *drv = dev->driver;
772 	int ret = 0;
773 
774 	if (!drv)
775 		return 0;
776 
777 	if (drv->pm) {
778 		if (drv->pm->resume_noirq)
779 			ret = drv->pm->resume_noirq(dev);
780 	} else {
781 		ret = platform_legacy_resume_early(dev);
782 	}
783 
784 	return ret;
785 }
786 
787 #else /* !CONFIG_SUSPEND */
788 
789 #define platform_pm_suspend		NULL
790 #define platform_pm_resume		NULL
791 #define platform_pm_suspend_noirq	NULL
792 #define platform_pm_resume_noirq	NULL
793 
794 #endif /* !CONFIG_SUSPEND */
795 
796 #ifdef CONFIG_HIBERNATION
797 
798 static int platform_pm_freeze(struct device *dev)
799 {
800 	struct device_driver *drv = dev->driver;
801 	int ret = 0;
802 
803 	if (!drv)
804 		return 0;
805 
806 	if (drv->pm) {
807 		if (drv->pm->freeze)
808 			ret = drv->pm->freeze(dev);
809 	} else {
810 		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
811 	}
812 
813 	return ret;
814 }
815 
816 static int platform_pm_freeze_noirq(struct device *dev)
817 {
818 	struct device_driver *drv = dev->driver;
819 	int ret = 0;
820 
821 	if (!drv)
822 		return 0;
823 
824 	if (drv->pm) {
825 		if (drv->pm->freeze_noirq)
826 			ret = drv->pm->freeze_noirq(dev);
827 	} else {
828 		ret = platform_legacy_suspend_late(dev, PMSG_FREEZE);
829 	}
830 
831 	return ret;
832 }
833 
834 static int platform_pm_thaw(struct device *dev)
835 {
836 	struct device_driver *drv = dev->driver;
837 	int ret = 0;
838 
839 	if (!drv)
840 		return 0;
841 
842 	if (drv->pm) {
843 		if (drv->pm->thaw)
844 			ret = drv->pm->thaw(dev);
845 	} else {
846 		ret = platform_legacy_resume(dev);
847 	}
848 
849 	return ret;
850 }
851 
852 static int platform_pm_thaw_noirq(struct device *dev)
853 {
854 	struct device_driver *drv = dev->driver;
855 	int ret = 0;
856 
857 	if (!drv)
858 		return 0;
859 
860 	if (drv->pm) {
861 		if (drv->pm->thaw_noirq)
862 			ret = drv->pm->thaw_noirq(dev);
863 	} else {
864 		ret = platform_legacy_resume_early(dev);
865 	}
866 
867 	return ret;
868 }
869 
870 static int platform_pm_poweroff(struct device *dev)
871 {
872 	struct device_driver *drv = dev->driver;
873 	int ret = 0;
874 
875 	if (!drv)
876 		return 0;
877 
878 	if (drv->pm) {
879 		if (drv->pm->poweroff)
880 			ret = drv->pm->poweroff(dev);
881 	} else {
882 		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
883 	}
884 
885 	return ret;
886 }
887 
888 static int platform_pm_poweroff_noirq(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->poweroff_noirq)
898 			ret = drv->pm->poweroff_noirq(dev);
899 	} else {
900 		ret = platform_legacy_suspend_late(dev, PMSG_HIBERNATE);
901 	}
902 
903 	return ret;
904 }
905 
906 static int platform_pm_restore(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)
916 			ret = drv->pm->restore(dev);
917 	} else {
918 		ret = platform_legacy_resume(dev);
919 	}
920 
921 	return ret;
922 }
923 
924 static int platform_pm_restore_noirq(struct device *dev)
925 {
926 	struct device_driver *drv = dev->driver;
927 	int ret = 0;
928 
929 	if (!drv)
930 		return 0;
931 
932 	if (drv->pm) {
933 		if (drv->pm->restore_noirq)
934 			ret = drv->pm->restore_noirq(dev);
935 	} else {
936 		ret = platform_legacy_resume_early(dev);
937 	}
938 
939 	return ret;
940 }
941 
942 #else /* !CONFIG_HIBERNATION */
943 
944 #define platform_pm_freeze		NULL
945 #define platform_pm_thaw		NULL
946 #define platform_pm_poweroff		NULL
947 #define platform_pm_restore		NULL
948 #define platform_pm_freeze_noirq	NULL
949 #define platform_pm_thaw_noirq		NULL
950 #define platform_pm_poweroff_noirq	NULL
951 #define platform_pm_restore_noirq	NULL
952 
953 #endif /* !CONFIG_HIBERNATION */
954 
955 static struct dev_pm_ops platform_dev_pm_ops = {
956 	.prepare = platform_pm_prepare,
957 	.complete = platform_pm_complete,
958 	.suspend = platform_pm_suspend,
959 	.resume = platform_pm_resume,
960 	.freeze = platform_pm_freeze,
961 	.thaw = platform_pm_thaw,
962 	.poweroff = platform_pm_poweroff,
963 	.restore = platform_pm_restore,
964 	.suspend_noirq = platform_pm_suspend_noirq,
965 	.resume_noirq = platform_pm_resume_noirq,
966 	.freeze_noirq = platform_pm_freeze_noirq,
967 	.thaw_noirq = platform_pm_thaw_noirq,
968 	.poweroff_noirq = platform_pm_poweroff_noirq,
969 	.restore_noirq = platform_pm_restore_noirq,
970 };
971 
972 #define PLATFORM_PM_OPS_PTR	(&platform_dev_pm_ops)
973 
974 #else /* !CONFIG_PM_SLEEP */
975 
976 #define PLATFORM_PM_OPS_PTR	NULL
977 
978 #endif /* !CONFIG_PM_SLEEP */
979 
980 struct bus_type platform_bus_type = {
981 	.name		= "platform",
982 	.dev_attrs	= platform_dev_attrs,
983 	.match		= platform_match,
984 	.uevent		= platform_uevent,
985 	.pm		= PLATFORM_PM_OPS_PTR,
986 };
987 EXPORT_SYMBOL_GPL(platform_bus_type);
988 
989 int __init platform_bus_init(void)
990 {
991 	int error;
992 
993 	error = device_register(&platform_bus);
994 	if (error)
995 		return error;
996 	error =  bus_register(&platform_bus_type);
997 	if (error)
998 		device_unregister(&platform_bus);
999 	return error;
1000 }
1001 
1002 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1003 u64 dma_get_required_mask(struct device *dev)
1004 {
1005 	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1006 	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1007 	u64 mask;
1008 
1009 	if (!high_totalram) {
1010 		/* convert to mask just covering totalram */
1011 		low_totalram = (1 << (fls(low_totalram) - 1));
1012 		low_totalram += low_totalram - 1;
1013 		mask = low_totalram;
1014 	} else {
1015 		high_totalram = (1 << (fls(high_totalram) - 1));
1016 		high_totalram += high_totalram - 1;
1017 		mask = (((u64)high_totalram) << 32) + 0xffffffff;
1018 	}
1019 	return mask;
1020 }
1021 EXPORT_SYMBOL_GPL(dma_get_required_mask);
1022 #endif
1023