xref: /openbmc/linux/drivers/base/platform.c (revision 79f382b9)
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/interrupt.h>
19 #include <linux/ioport.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/memblock.h>
22 #include <linux/err.h>
23 #include <linux/slab.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/pm_domain.h>
26 #include <linux/idr.h>
27 #include <linux/acpi.h>
28 #include <linux/clk/clk-conf.h>
29 #include <linux/limits.h>
30 #include <linux/property.h>
31 #include <linux/kmemleak.h>
32 #include <linux/types.h>
33 
34 #include "base.h"
35 #include "power/power.h"
36 
37 /* For automatically allocated device IDs */
38 static DEFINE_IDA(platform_devid_ida);
39 
40 struct device platform_bus = {
41 	.init_name	= "platform",
42 };
43 EXPORT_SYMBOL_GPL(platform_bus);
44 
45 /**
46  * platform_get_resource - get a resource for a device
47  * @dev: platform device
48  * @type: resource type
49  * @num: resource index
50  *
51  * Return: a pointer to the resource or NULL on failure.
52  */
53 struct resource *platform_get_resource(struct platform_device *dev,
54 				       unsigned int type, unsigned int num)
55 {
56 	u32 i;
57 
58 	for (i = 0; i < dev->num_resources; i++) {
59 		struct resource *r = &dev->resource[i];
60 
61 		if (type == resource_type(r) && num-- == 0)
62 			return r;
63 	}
64 	return NULL;
65 }
66 EXPORT_SYMBOL_GPL(platform_get_resource);
67 
68 struct resource *platform_get_mem_or_io(struct platform_device *dev,
69 					unsigned int num)
70 {
71 	u32 i;
72 
73 	for (i = 0; i < dev->num_resources; i++) {
74 		struct resource *r = &dev->resource[i];
75 
76 		if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
77 			return r;
78 	}
79 	return NULL;
80 }
81 EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
82 
83 #ifdef CONFIG_HAS_IOMEM
84 /**
85  * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
86  *					    platform device and get resource
87  *
88  * @pdev: platform device to use both for memory resource lookup as well as
89  *        resource management
90  * @index: resource index
91  * @res: optional output parameter to store a pointer to the obtained resource.
92  *
93  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
94  * on failure.
95  */
96 void __iomem *
97 devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
98 				unsigned int index, struct resource **res)
99 {
100 	struct resource *r;
101 
102 	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
103 	if (res)
104 		*res = r;
105 	return devm_ioremap_resource(&pdev->dev, r);
106 }
107 EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
108 
109 /**
110  * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
111  *				    device
112  *
113  * @pdev: platform device to use both for memory resource lookup as well as
114  *        resource management
115  * @index: resource index
116  *
117  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
118  * on failure.
119  */
120 void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
121 					     unsigned int index)
122 {
123 	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
124 }
125 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
126 
127 /**
128  * devm_platform_ioremap_resource_wc - write-combined variant of
129  *                                     devm_platform_ioremap_resource()
130  *
131  * @pdev: platform device to use both for memory resource lookup as well as
132  *        resource management
133  * @index: resource index
134  *
135  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
136  * on failure.
137  */
138 void __iomem *devm_platform_ioremap_resource_wc(struct platform_device *pdev,
139 						unsigned int index)
140 {
141 	struct resource *res;
142 
143 	res = platform_get_resource(pdev, IORESOURCE_MEM, index);
144 	return devm_ioremap_resource_wc(&pdev->dev, res);
145 }
146 
147 /**
148  * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
149  *					   a platform device, retrieve the
150  *					   resource by name
151  *
152  * @pdev: platform device to use both for memory resource lookup as well as
153  *	  resource management
154  * @name: name of the resource
155  *
156  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
157  * on failure.
158  */
159 void __iomem *
160 devm_platform_ioremap_resource_byname(struct platform_device *pdev,
161 				      const char *name)
162 {
163 	struct resource *res;
164 
165 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
166 	return devm_ioremap_resource(&pdev->dev, res);
167 }
168 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
169 #endif /* CONFIG_HAS_IOMEM */
170 
171 /**
172  * platform_get_irq_optional - get an optional IRQ for a device
173  * @dev: platform device
174  * @num: IRQ number index
175  *
176  * Gets an IRQ for a platform device. Device drivers should check the return
177  * value for errors so as to not pass a negative integer value to the
178  * request_irq() APIs. This is the same as platform_get_irq(), except that it
179  * does not print an error message if an IRQ can not be obtained.
180  *
181  * For example::
182  *
183  *		int irq = platform_get_irq_optional(pdev, 0);
184  *		if (irq < 0)
185  *			return irq;
186  *
187  * Return: non-zero IRQ number on success, negative error number on failure.
188  */
189 int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
190 {
191 	int ret;
192 #ifdef CONFIG_SPARC
193 	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
194 	if (!dev || num >= dev->archdata.num_irqs)
195 		return -ENXIO;
196 	ret = dev->archdata.irqs[num];
197 	goto out;
198 #else
199 	struct resource *r;
200 
201 	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
202 		ret = of_irq_get(dev->dev.of_node, num);
203 		if (ret > 0 || ret == -EPROBE_DEFER)
204 			goto out;
205 	}
206 
207 	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
208 	if (has_acpi_companion(&dev->dev)) {
209 		if (r && r->flags & IORESOURCE_DISABLED) {
210 			ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
211 			if (ret)
212 				goto out;
213 		}
214 	}
215 
216 	/*
217 	 * The resources may pass trigger flags to the irqs that need
218 	 * to be set up. It so happens that the trigger flags for
219 	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
220 	 * settings.
221 	 */
222 	if (r && r->flags & IORESOURCE_BITS) {
223 		struct irq_data *irqd;
224 
225 		irqd = irq_get_irq_data(r->start);
226 		if (!irqd) {
227 			ret = -ENXIO;
228 			goto out;
229 		}
230 		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
231 	}
232 
233 	if (r) {
234 		ret = r->start;
235 		goto out;
236 	}
237 
238 	/*
239 	 * For the index 0 interrupt, allow falling back to GpioInt
240 	 * resources. While a device could have both Interrupt and GpioInt
241 	 * resources, making this fallback ambiguous, in many common cases
242 	 * the device will only expose one IRQ, and this fallback
243 	 * allows a common code path across either kind of resource.
244 	 */
245 	if (num == 0 && has_acpi_companion(&dev->dev)) {
246 		ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
247 		/* Our callers expect -ENXIO for missing IRQs. */
248 		if (ret >= 0 || ret == -EPROBE_DEFER)
249 			goto out;
250 	}
251 
252 	ret = -ENXIO;
253 #endif
254 out:
255 	WARN(ret == 0, "0 is an invalid IRQ number\n");
256 	return ret;
257 }
258 EXPORT_SYMBOL_GPL(platform_get_irq_optional);
259 
260 /**
261  * platform_get_irq - get an IRQ for a device
262  * @dev: platform device
263  * @num: IRQ number index
264  *
265  * Gets an IRQ for a platform device and prints an error message if finding the
266  * IRQ fails. Device drivers should check the return value for errors so as to
267  * not pass a negative integer value to the request_irq() APIs.
268  *
269  * For example::
270  *
271  *		int irq = platform_get_irq(pdev, 0);
272  *		if (irq < 0)
273  *			return irq;
274  *
275  * Return: non-zero IRQ number on success, negative error number on failure.
276  */
277 int platform_get_irq(struct platform_device *dev, unsigned int num)
278 {
279 	int ret;
280 
281 	ret = platform_get_irq_optional(dev, num);
282 	if (ret < 0 && ret != -EPROBE_DEFER)
283 		dev_err(&dev->dev, "IRQ index %u not found\n", num);
284 
285 	return ret;
286 }
287 EXPORT_SYMBOL_GPL(platform_get_irq);
288 
289 /**
290  * platform_irq_count - Count the number of IRQs a platform device uses
291  * @dev: platform device
292  *
293  * Return: Number of IRQs a platform device uses or EPROBE_DEFER
294  */
295 int platform_irq_count(struct platform_device *dev)
296 {
297 	int ret, nr = 0;
298 
299 	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
300 		nr++;
301 
302 	if (ret == -EPROBE_DEFER)
303 		return ret;
304 
305 	return nr;
306 }
307 EXPORT_SYMBOL_GPL(platform_irq_count);
308 
309 struct irq_affinity_devres {
310 	unsigned int count;
311 	unsigned int irq[];
312 };
313 
314 static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
315 {
316 	struct resource *r;
317 
318 	r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
319 	if (r)
320 		irqresource_disabled(r, 0);
321 }
322 
323 static void devm_platform_get_irqs_affinity_release(struct device *dev,
324 						    void *res)
325 {
326 	struct irq_affinity_devres *ptr = res;
327 	int i;
328 
329 	for (i = 0; i < ptr->count; i++) {
330 		irq_dispose_mapping(ptr->irq[i]);
331 
332 		if (has_acpi_companion(dev))
333 			platform_disable_acpi_irq(to_platform_device(dev), i);
334 	}
335 }
336 
337 /**
338  * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
339  *				device using an interrupt affinity descriptor
340  * @dev: platform device pointer
341  * @affd: affinity descriptor
342  * @minvec: minimum count of interrupt vectors
343  * @maxvec: maximum count of interrupt vectors
344  * @irqs: pointer holder for IRQ numbers
345  *
346  * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
347  * to the passed affinity descriptor
348  *
349  * Return: Number of vectors on success, negative error number on failure.
350  */
351 int devm_platform_get_irqs_affinity(struct platform_device *dev,
352 				    struct irq_affinity *affd,
353 				    unsigned int minvec,
354 				    unsigned int maxvec,
355 				    int **irqs)
356 {
357 	struct irq_affinity_devres *ptr;
358 	struct irq_affinity_desc *desc;
359 	size_t size;
360 	int i, ret, nvec;
361 
362 	if (!affd)
363 		return -EPERM;
364 
365 	if (maxvec < minvec)
366 		return -ERANGE;
367 
368 	nvec = platform_irq_count(dev);
369 	if (nvec < 0)
370 		return nvec;
371 
372 	if (nvec < minvec)
373 		return -ENOSPC;
374 
375 	nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
376 	if (nvec < minvec)
377 		return -ENOSPC;
378 
379 	if (nvec > maxvec)
380 		nvec = maxvec;
381 
382 	size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
383 	ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
384 			   GFP_KERNEL);
385 	if (!ptr)
386 		return -ENOMEM;
387 
388 	ptr->count = nvec;
389 
390 	for (i = 0; i < nvec; i++) {
391 		int irq = platform_get_irq(dev, i);
392 		if (irq < 0) {
393 			ret = irq;
394 			goto err_free_devres;
395 		}
396 		ptr->irq[i] = irq;
397 	}
398 
399 	desc = irq_create_affinity_masks(nvec, affd);
400 	if (!desc) {
401 		ret = -ENOMEM;
402 		goto err_free_devres;
403 	}
404 
405 	for (i = 0; i < nvec; i++) {
406 		ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
407 		if (ret) {
408 			dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
409 				ptr->irq[i], ret);
410 			goto err_free_desc;
411 		}
412 	}
413 
414 	devres_add(&dev->dev, ptr);
415 
416 	kfree(desc);
417 
418 	*irqs = ptr->irq;
419 
420 	return nvec;
421 
422 err_free_desc:
423 	kfree(desc);
424 err_free_devres:
425 	devres_free(ptr);
426 	return ret;
427 }
428 EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
429 
430 /**
431  * platform_get_resource_byname - get a resource for a device by name
432  * @dev: platform device
433  * @type: resource type
434  * @name: resource name
435  */
436 struct resource *platform_get_resource_byname(struct platform_device *dev,
437 					      unsigned int type,
438 					      const char *name)
439 {
440 	u32 i;
441 
442 	for (i = 0; i < dev->num_resources; i++) {
443 		struct resource *r = &dev->resource[i];
444 
445 		if (unlikely(!r->name))
446 			continue;
447 
448 		if (type == resource_type(r) && !strcmp(r->name, name))
449 			return r;
450 	}
451 	return NULL;
452 }
453 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
454 
455 static int __platform_get_irq_byname(struct platform_device *dev,
456 				     const char *name)
457 {
458 	struct resource *r;
459 	int ret;
460 
461 	if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
462 		ret = of_irq_get_byname(dev->dev.of_node, name);
463 		if (ret > 0 || ret == -EPROBE_DEFER)
464 			return ret;
465 	}
466 
467 	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
468 	if (r) {
469 		WARN(r->start == 0, "0 is an invalid IRQ number\n");
470 		return r->start;
471 	}
472 
473 	return -ENXIO;
474 }
475 
476 /**
477  * platform_get_irq_byname - get an IRQ for a device by name
478  * @dev: platform device
479  * @name: IRQ name
480  *
481  * Get an IRQ like platform_get_irq(), but then by name rather then by index.
482  *
483  * Return: non-zero IRQ number on success, negative error number on failure.
484  */
485 int platform_get_irq_byname(struct platform_device *dev, const char *name)
486 {
487 	int ret;
488 
489 	ret = __platform_get_irq_byname(dev, name);
490 	if (ret < 0 && ret != -EPROBE_DEFER)
491 		dev_err(&dev->dev, "IRQ %s not found\n", name);
492 
493 	return ret;
494 }
495 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
496 
497 /**
498  * platform_get_irq_byname_optional - get an optional IRQ for a device by name
499  * @dev: platform device
500  * @name: IRQ name
501  *
502  * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
503  * does not print an error message if an IRQ can not be obtained.
504  *
505  * Return: non-zero IRQ number on success, negative error number on failure.
506  */
507 int platform_get_irq_byname_optional(struct platform_device *dev,
508 				     const char *name)
509 {
510 	return __platform_get_irq_byname(dev, name);
511 }
512 EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
513 
514 /**
515  * platform_add_devices - add a numbers of platform devices
516  * @devs: array of platform devices to add
517  * @num: number of platform devices in array
518  */
519 int platform_add_devices(struct platform_device **devs, int num)
520 {
521 	int i, ret = 0;
522 
523 	for (i = 0; i < num; i++) {
524 		ret = platform_device_register(devs[i]);
525 		if (ret) {
526 			while (--i >= 0)
527 				platform_device_unregister(devs[i]);
528 			break;
529 		}
530 	}
531 
532 	return ret;
533 }
534 EXPORT_SYMBOL_GPL(platform_add_devices);
535 
536 struct platform_object {
537 	struct platform_device pdev;
538 	char name[];
539 };
540 
541 /*
542  * Set up default DMA mask for platform devices if the they weren't
543  * previously set by the architecture / DT.
544  */
545 static void setup_pdev_dma_masks(struct platform_device *pdev)
546 {
547 	pdev->dev.dma_parms = &pdev->dma_parms;
548 
549 	if (!pdev->dev.coherent_dma_mask)
550 		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
551 	if (!pdev->dev.dma_mask) {
552 		pdev->platform_dma_mask = DMA_BIT_MASK(32);
553 		pdev->dev.dma_mask = &pdev->platform_dma_mask;
554 	}
555 };
556 
557 /**
558  * platform_device_put - destroy a platform device
559  * @pdev: platform device to free
560  *
561  * Free all memory associated with a platform device.  This function must
562  * _only_ be externally called in error cases.  All other usage is a bug.
563  */
564 void platform_device_put(struct platform_device *pdev)
565 {
566 	if (!IS_ERR_OR_NULL(pdev))
567 		put_device(&pdev->dev);
568 }
569 EXPORT_SYMBOL_GPL(platform_device_put);
570 
571 static void platform_device_release(struct device *dev)
572 {
573 	struct platform_object *pa = container_of(dev, struct platform_object,
574 						  pdev.dev);
575 
576 	of_node_put(pa->pdev.dev.of_node);
577 	kfree(pa->pdev.dev.platform_data);
578 	kfree(pa->pdev.mfd_cell);
579 	kfree(pa->pdev.resource);
580 	kfree(pa->pdev.driver_override);
581 	kfree(pa);
582 }
583 
584 /**
585  * platform_device_alloc - create a platform device
586  * @name: base name of the device we're adding
587  * @id: instance id
588  *
589  * Create a platform device object which can have other objects attached
590  * to it, and which will have attached objects freed when it is released.
591  */
592 struct platform_device *platform_device_alloc(const char *name, int id)
593 {
594 	struct platform_object *pa;
595 
596 	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
597 	if (pa) {
598 		strcpy(pa->name, name);
599 		pa->pdev.name = pa->name;
600 		pa->pdev.id = id;
601 		device_initialize(&pa->pdev.dev);
602 		pa->pdev.dev.release = platform_device_release;
603 		setup_pdev_dma_masks(&pa->pdev);
604 	}
605 
606 	return pa ? &pa->pdev : NULL;
607 }
608 EXPORT_SYMBOL_GPL(platform_device_alloc);
609 
610 /**
611  * platform_device_add_resources - add resources to a platform device
612  * @pdev: platform device allocated by platform_device_alloc to add resources to
613  * @res: set of resources that needs to be allocated for the device
614  * @num: number of resources
615  *
616  * Add a copy of the resources to the platform device.  The memory
617  * associated with the resources will be freed when the platform device is
618  * released.
619  */
620 int platform_device_add_resources(struct platform_device *pdev,
621 				  const struct resource *res, unsigned int num)
622 {
623 	struct resource *r = NULL;
624 
625 	if (res) {
626 		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
627 		if (!r)
628 			return -ENOMEM;
629 	}
630 
631 	kfree(pdev->resource);
632 	pdev->resource = r;
633 	pdev->num_resources = num;
634 	return 0;
635 }
636 EXPORT_SYMBOL_GPL(platform_device_add_resources);
637 
638 /**
639  * platform_device_add_data - add platform-specific data to a platform device
640  * @pdev: platform device allocated by platform_device_alloc to add resources to
641  * @data: platform specific data for this platform device
642  * @size: size of platform specific data
643  *
644  * Add a copy of platform specific data to the platform device's
645  * platform_data pointer.  The memory associated with the platform data
646  * will be freed when the platform device is released.
647  */
648 int platform_device_add_data(struct platform_device *pdev, const void *data,
649 			     size_t size)
650 {
651 	void *d = NULL;
652 
653 	if (data) {
654 		d = kmemdup(data, size, GFP_KERNEL);
655 		if (!d)
656 			return -ENOMEM;
657 	}
658 
659 	kfree(pdev->dev.platform_data);
660 	pdev->dev.platform_data = d;
661 	return 0;
662 }
663 EXPORT_SYMBOL_GPL(platform_device_add_data);
664 
665 /**
666  * platform_device_add_properties - add built-in properties to a platform device
667  * @pdev: platform device to add properties to
668  * @properties: null terminated array of properties to add
669  *
670  * The function will take deep copy of @properties and attach the copy to the
671  * platform device. The memory associated with properties will be freed when the
672  * platform device is released.
673  */
674 int platform_device_add_properties(struct platform_device *pdev,
675 				   const struct property_entry *properties)
676 {
677 	return device_add_properties(&pdev->dev, properties);
678 }
679 EXPORT_SYMBOL_GPL(platform_device_add_properties);
680 
681 /**
682  * platform_device_add - add a platform device to device hierarchy
683  * @pdev: platform device we're adding
684  *
685  * This is part 2 of platform_device_register(), though may be called
686  * separately _iff_ pdev was allocated by platform_device_alloc().
687  */
688 int platform_device_add(struct platform_device *pdev)
689 {
690 	u32 i;
691 	int ret;
692 
693 	if (!pdev)
694 		return -EINVAL;
695 
696 	if (!pdev->dev.parent)
697 		pdev->dev.parent = &platform_bus;
698 
699 	pdev->dev.bus = &platform_bus_type;
700 
701 	switch (pdev->id) {
702 	default:
703 		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
704 		break;
705 	case PLATFORM_DEVID_NONE:
706 		dev_set_name(&pdev->dev, "%s", pdev->name);
707 		break;
708 	case PLATFORM_DEVID_AUTO:
709 		/*
710 		 * Automatically allocated device ID. We mark it as such so
711 		 * that we remember it must be freed, and we append a suffix
712 		 * to avoid namespace collision with explicit IDs.
713 		 */
714 		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
715 		if (ret < 0)
716 			goto err_out;
717 		pdev->id = ret;
718 		pdev->id_auto = true;
719 		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
720 		break;
721 	}
722 
723 	for (i = 0; i < pdev->num_resources; i++) {
724 		struct resource *p, *r = &pdev->resource[i];
725 
726 		if (r->name == NULL)
727 			r->name = dev_name(&pdev->dev);
728 
729 		p = r->parent;
730 		if (!p) {
731 			if (resource_type(r) == IORESOURCE_MEM)
732 				p = &iomem_resource;
733 			else if (resource_type(r) == IORESOURCE_IO)
734 				p = &ioport_resource;
735 		}
736 
737 		if (p) {
738 			ret = insert_resource(p, r);
739 			if (ret) {
740 				dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
741 				goto failed;
742 			}
743 		}
744 	}
745 
746 	pr_debug("Registering platform device '%s'. Parent at %s\n",
747 		 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
748 
749 	ret = device_add(&pdev->dev);
750 	if (ret == 0)
751 		return ret;
752 
753  failed:
754 	if (pdev->id_auto) {
755 		ida_free(&platform_devid_ida, pdev->id);
756 		pdev->id = PLATFORM_DEVID_AUTO;
757 	}
758 
759 	while (i--) {
760 		struct resource *r = &pdev->resource[i];
761 		if (r->parent)
762 			release_resource(r);
763 	}
764 
765  err_out:
766 	return ret;
767 }
768 EXPORT_SYMBOL_GPL(platform_device_add);
769 
770 /**
771  * platform_device_del - remove a platform-level device
772  * @pdev: platform device we're removing
773  *
774  * Note that this function will also release all memory- and port-based
775  * resources owned by the device (@dev->resource).  This function must
776  * _only_ be externally called in error cases.  All other usage is a bug.
777  */
778 void platform_device_del(struct platform_device *pdev)
779 {
780 	u32 i;
781 
782 	if (!IS_ERR_OR_NULL(pdev)) {
783 		device_del(&pdev->dev);
784 
785 		if (pdev->id_auto) {
786 			ida_free(&platform_devid_ida, pdev->id);
787 			pdev->id = PLATFORM_DEVID_AUTO;
788 		}
789 
790 		for (i = 0; i < pdev->num_resources; i++) {
791 			struct resource *r = &pdev->resource[i];
792 			if (r->parent)
793 				release_resource(r);
794 		}
795 	}
796 }
797 EXPORT_SYMBOL_GPL(platform_device_del);
798 
799 /**
800  * platform_device_register - add a platform-level device
801  * @pdev: platform device we're adding
802  */
803 int platform_device_register(struct platform_device *pdev)
804 {
805 	device_initialize(&pdev->dev);
806 	setup_pdev_dma_masks(pdev);
807 	return platform_device_add(pdev);
808 }
809 EXPORT_SYMBOL_GPL(platform_device_register);
810 
811 /**
812  * platform_device_unregister - unregister a platform-level device
813  * @pdev: platform device we're unregistering
814  *
815  * Unregistration is done in 2 steps. First we release all resources
816  * and remove it from the subsystem, then we drop reference count by
817  * calling platform_device_put().
818  */
819 void platform_device_unregister(struct platform_device *pdev)
820 {
821 	platform_device_del(pdev);
822 	platform_device_put(pdev);
823 }
824 EXPORT_SYMBOL_GPL(platform_device_unregister);
825 
826 /**
827  * platform_device_register_full - add a platform-level device with
828  * resources and platform-specific data
829  *
830  * @pdevinfo: data used to create device
831  *
832  * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
833  */
834 struct platform_device *platform_device_register_full(
835 		const struct platform_device_info *pdevinfo)
836 {
837 	int ret;
838 	struct platform_device *pdev;
839 
840 	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
841 	if (!pdev)
842 		return ERR_PTR(-ENOMEM);
843 
844 	pdev->dev.parent = pdevinfo->parent;
845 	pdev->dev.fwnode = pdevinfo->fwnode;
846 	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
847 	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
848 
849 	if (pdevinfo->dma_mask) {
850 		pdev->platform_dma_mask = pdevinfo->dma_mask;
851 		pdev->dev.dma_mask = &pdev->platform_dma_mask;
852 		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
853 	}
854 
855 	ret = platform_device_add_resources(pdev,
856 			pdevinfo->res, pdevinfo->num_res);
857 	if (ret)
858 		goto err;
859 
860 	ret = platform_device_add_data(pdev,
861 			pdevinfo->data, pdevinfo->size_data);
862 	if (ret)
863 		goto err;
864 
865 	if (pdevinfo->properties) {
866 		ret = platform_device_add_properties(pdev,
867 						     pdevinfo->properties);
868 		if (ret)
869 			goto err;
870 	}
871 
872 	ret = platform_device_add(pdev);
873 	if (ret) {
874 err:
875 		ACPI_COMPANION_SET(&pdev->dev, NULL);
876 		platform_device_put(pdev);
877 		return ERR_PTR(ret);
878 	}
879 
880 	return pdev;
881 }
882 EXPORT_SYMBOL_GPL(platform_device_register_full);
883 
884 /**
885  * __platform_driver_register - register a driver for platform-level devices
886  * @drv: platform driver structure
887  * @owner: owning module/driver
888  */
889 int __platform_driver_register(struct platform_driver *drv,
890 				struct module *owner)
891 {
892 	drv->driver.owner = owner;
893 	drv->driver.bus = &platform_bus_type;
894 
895 	return driver_register(&drv->driver);
896 }
897 EXPORT_SYMBOL_GPL(__platform_driver_register);
898 
899 /**
900  * platform_driver_unregister - unregister a driver for platform-level devices
901  * @drv: platform driver structure
902  */
903 void platform_driver_unregister(struct platform_driver *drv)
904 {
905 	driver_unregister(&drv->driver);
906 }
907 EXPORT_SYMBOL_GPL(platform_driver_unregister);
908 
909 static int platform_probe_fail(struct platform_device *pdev)
910 {
911 	return -ENXIO;
912 }
913 
914 /**
915  * __platform_driver_probe - register driver for non-hotpluggable device
916  * @drv: platform driver structure
917  * @probe: the driver probe routine, probably from an __init section
918  * @module: module which will be the owner of the driver
919  *
920  * Use this instead of platform_driver_register() when you know the device
921  * is not hotpluggable and has already been registered, and you want to
922  * remove its run-once probe() infrastructure from memory after the driver
923  * has bound to the device.
924  *
925  * One typical use for this would be with drivers for controllers integrated
926  * into system-on-chip processors, where the controller devices have been
927  * configured as part of board setup.
928  *
929  * Note that this is incompatible with deferred probing.
930  *
931  * Returns zero if the driver registered and bound to a device, else returns
932  * a negative error code and with the driver not registered.
933  */
934 int __init_or_module __platform_driver_probe(struct platform_driver *drv,
935 		int (*probe)(struct platform_device *), struct module *module)
936 {
937 	int retval, code;
938 
939 	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
940 		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
941 			 drv->driver.name, __func__);
942 		return -EINVAL;
943 	}
944 
945 	/*
946 	 * We have to run our probes synchronously because we check if
947 	 * we find any devices to bind to and exit with error if there
948 	 * are any.
949 	 */
950 	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
951 
952 	/*
953 	 * Prevent driver from requesting probe deferral to avoid further
954 	 * futile probe attempts.
955 	 */
956 	drv->prevent_deferred_probe = true;
957 
958 	/* make sure driver won't have bind/unbind attributes */
959 	drv->driver.suppress_bind_attrs = true;
960 
961 	/* temporary section violation during probe() */
962 	drv->probe = probe;
963 	retval = code = __platform_driver_register(drv, module);
964 	if (retval)
965 		return retval;
966 
967 	/*
968 	 * Fixup that section violation, being paranoid about code scanning
969 	 * the list of drivers in order to probe new devices.  Check to see
970 	 * if the probe was successful, and make sure any forced probes of
971 	 * new devices fail.
972 	 */
973 	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
974 	drv->probe = platform_probe_fail;
975 	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
976 		retval = -ENODEV;
977 	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
978 
979 	if (code != retval)
980 		platform_driver_unregister(drv);
981 	return retval;
982 }
983 EXPORT_SYMBOL_GPL(__platform_driver_probe);
984 
985 /**
986  * __platform_create_bundle - register driver and create corresponding device
987  * @driver: platform driver structure
988  * @probe: the driver probe routine, probably from an __init section
989  * @res: set of resources that needs to be allocated for the device
990  * @n_res: number of resources
991  * @data: platform specific data for this platform device
992  * @size: size of platform specific data
993  * @module: module which will be the owner of the driver
994  *
995  * Use this in legacy-style modules that probe hardware directly and
996  * register a single platform device and corresponding platform driver.
997  *
998  * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
999  */
1000 struct platform_device * __init_or_module __platform_create_bundle(
1001 			struct platform_driver *driver,
1002 			int (*probe)(struct platform_device *),
1003 			struct resource *res, unsigned int n_res,
1004 			const void *data, size_t size, struct module *module)
1005 {
1006 	struct platform_device *pdev;
1007 	int error;
1008 
1009 	pdev = platform_device_alloc(driver->driver.name, -1);
1010 	if (!pdev) {
1011 		error = -ENOMEM;
1012 		goto err_out;
1013 	}
1014 
1015 	error = platform_device_add_resources(pdev, res, n_res);
1016 	if (error)
1017 		goto err_pdev_put;
1018 
1019 	error = platform_device_add_data(pdev, data, size);
1020 	if (error)
1021 		goto err_pdev_put;
1022 
1023 	error = platform_device_add(pdev);
1024 	if (error)
1025 		goto err_pdev_put;
1026 
1027 	error = __platform_driver_probe(driver, probe, module);
1028 	if (error)
1029 		goto err_pdev_del;
1030 
1031 	return pdev;
1032 
1033 err_pdev_del:
1034 	platform_device_del(pdev);
1035 err_pdev_put:
1036 	platform_device_put(pdev);
1037 err_out:
1038 	return ERR_PTR(error);
1039 }
1040 EXPORT_SYMBOL_GPL(__platform_create_bundle);
1041 
1042 /**
1043  * __platform_register_drivers - register an array of platform drivers
1044  * @drivers: an array of drivers to register
1045  * @count: the number of drivers to register
1046  * @owner: module owning the drivers
1047  *
1048  * Registers platform drivers specified by an array. On failure to register a
1049  * driver, all previously registered drivers will be unregistered. Callers of
1050  * this API should use platform_unregister_drivers() to unregister drivers in
1051  * the reverse order.
1052  *
1053  * Returns: 0 on success or a negative error code on failure.
1054  */
1055 int __platform_register_drivers(struct platform_driver * const *drivers,
1056 				unsigned int count, struct module *owner)
1057 {
1058 	unsigned int i;
1059 	int err;
1060 
1061 	for (i = 0; i < count; i++) {
1062 		pr_debug("registering platform driver %ps\n", drivers[i]);
1063 
1064 		err = __platform_driver_register(drivers[i], owner);
1065 		if (err < 0) {
1066 			pr_err("failed to register platform driver %ps: %d\n",
1067 			       drivers[i], err);
1068 			goto error;
1069 		}
1070 	}
1071 
1072 	return 0;
1073 
1074 error:
1075 	while (i--) {
1076 		pr_debug("unregistering platform driver %ps\n", drivers[i]);
1077 		platform_driver_unregister(drivers[i]);
1078 	}
1079 
1080 	return err;
1081 }
1082 EXPORT_SYMBOL_GPL(__platform_register_drivers);
1083 
1084 /**
1085  * platform_unregister_drivers - unregister an array of platform drivers
1086  * @drivers: an array of drivers to unregister
1087  * @count: the number of drivers to unregister
1088  *
1089  * Unregisters platform drivers specified by an array. This is typically used
1090  * to complement an earlier call to platform_register_drivers(). Drivers are
1091  * unregistered in the reverse order in which they were registered.
1092  */
1093 void platform_unregister_drivers(struct platform_driver * const *drivers,
1094 				 unsigned int count)
1095 {
1096 	while (count--) {
1097 		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1098 		platform_driver_unregister(drivers[count]);
1099 	}
1100 }
1101 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1102 
1103 static const struct platform_device_id *platform_match_id(
1104 			const struct platform_device_id *id,
1105 			struct platform_device *pdev)
1106 {
1107 	while (id->name[0]) {
1108 		if (strcmp(pdev->name, id->name) == 0) {
1109 			pdev->id_entry = id;
1110 			return id;
1111 		}
1112 		id++;
1113 	}
1114 	return NULL;
1115 }
1116 
1117 #ifdef CONFIG_PM_SLEEP
1118 
1119 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1120 {
1121 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1122 	struct platform_device *pdev = to_platform_device(dev);
1123 	int ret = 0;
1124 
1125 	if (dev->driver && pdrv->suspend)
1126 		ret = pdrv->suspend(pdev, mesg);
1127 
1128 	return ret;
1129 }
1130 
1131 static int platform_legacy_resume(struct device *dev)
1132 {
1133 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1134 	struct platform_device *pdev = to_platform_device(dev);
1135 	int ret = 0;
1136 
1137 	if (dev->driver && pdrv->resume)
1138 		ret = pdrv->resume(pdev);
1139 
1140 	return ret;
1141 }
1142 
1143 #endif /* CONFIG_PM_SLEEP */
1144 
1145 #ifdef CONFIG_SUSPEND
1146 
1147 int platform_pm_suspend(struct device *dev)
1148 {
1149 	struct device_driver *drv = dev->driver;
1150 	int ret = 0;
1151 
1152 	if (!drv)
1153 		return 0;
1154 
1155 	if (drv->pm) {
1156 		if (drv->pm->suspend)
1157 			ret = drv->pm->suspend(dev);
1158 	} else {
1159 		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1160 	}
1161 
1162 	return ret;
1163 }
1164 
1165 int platform_pm_resume(struct device *dev)
1166 {
1167 	struct device_driver *drv = dev->driver;
1168 	int ret = 0;
1169 
1170 	if (!drv)
1171 		return 0;
1172 
1173 	if (drv->pm) {
1174 		if (drv->pm->resume)
1175 			ret = drv->pm->resume(dev);
1176 	} else {
1177 		ret = platform_legacy_resume(dev);
1178 	}
1179 
1180 	return ret;
1181 }
1182 
1183 #endif /* CONFIG_SUSPEND */
1184 
1185 #ifdef CONFIG_HIBERNATE_CALLBACKS
1186 
1187 int platform_pm_freeze(struct device *dev)
1188 {
1189 	struct device_driver *drv = dev->driver;
1190 	int ret = 0;
1191 
1192 	if (!drv)
1193 		return 0;
1194 
1195 	if (drv->pm) {
1196 		if (drv->pm->freeze)
1197 			ret = drv->pm->freeze(dev);
1198 	} else {
1199 		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1200 	}
1201 
1202 	return ret;
1203 }
1204 
1205 int platform_pm_thaw(struct device *dev)
1206 {
1207 	struct device_driver *drv = dev->driver;
1208 	int ret = 0;
1209 
1210 	if (!drv)
1211 		return 0;
1212 
1213 	if (drv->pm) {
1214 		if (drv->pm->thaw)
1215 			ret = drv->pm->thaw(dev);
1216 	} else {
1217 		ret = platform_legacy_resume(dev);
1218 	}
1219 
1220 	return ret;
1221 }
1222 
1223 int platform_pm_poweroff(struct device *dev)
1224 {
1225 	struct device_driver *drv = dev->driver;
1226 	int ret = 0;
1227 
1228 	if (!drv)
1229 		return 0;
1230 
1231 	if (drv->pm) {
1232 		if (drv->pm->poweroff)
1233 			ret = drv->pm->poweroff(dev);
1234 	} else {
1235 		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1236 	}
1237 
1238 	return ret;
1239 }
1240 
1241 int platform_pm_restore(struct device *dev)
1242 {
1243 	struct device_driver *drv = dev->driver;
1244 	int ret = 0;
1245 
1246 	if (!drv)
1247 		return 0;
1248 
1249 	if (drv->pm) {
1250 		if (drv->pm->restore)
1251 			ret = drv->pm->restore(dev);
1252 	} else {
1253 		ret = platform_legacy_resume(dev);
1254 	}
1255 
1256 	return ret;
1257 }
1258 
1259 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1260 
1261 /* modalias support enables more hands-off userspace setup:
1262  * (a) environment variable lets new-style hotplug events work once system is
1263  *     fully running:  "modprobe $MODALIAS"
1264  * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1265  *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1266  */
1267 static ssize_t modalias_show(struct device *dev,
1268 			     struct device_attribute *attr, char *buf)
1269 {
1270 	struct platform_device *pdev = to_platform_device(dev);
1271 	int len;
1272 
1273 	len = of_device_modalias(dev, buf, PAGE_SIZE);
1274 	if (len != -ENODEV)
1275 		return len;
1276 
1277 	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1278 	if (len != -ENODEV)
1279 		return len;
1280 
1281 	return sysfs_emit(buf, "platform:%s\n", pdev->name);
1282 }
1283 static DEVICE_ATTR_RO(modalias);
1284 
1285 static ssize_t numa_node_show(struct device *dev,
1286 			      struct device_attribute *attr, char *buf)
1287 {
1288 	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1289 }
1290 static DEVICE_ATTR_RO(numa_node);
1291 
1292 static ssize_t driver_override_show(struct device *dev,
1293 				    struct device_attribute *attr, char *buf)
1294 {
1295 	struct platform_device *pdev = to_platform_device(dev);
1296 	ssize_t len;
1297 
1298 	device_lock(dev);
1299 	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1300 	device_unlock(dev);
1301 
1302 	return len;
1303 }
1304 
1305 static ssize_t driver_override_store(struct device *dev,
1306 				     struct device_attribute *attr,
1307 				     const char *buf, size_t count)
1308 {
1309 	struct platform_device *pdev = to_platform_device(dev);
1310 	char *driver_override, *old, *cp;
1311 
1312 	/* We need to keep extra room for a newline */
1313 	if (count >= (PAGE_SIZE - 1))
1314 		return -EINVAL;
1315 
1316 	driver_override = kstrndup(buf, count, GFP_KERNEL);
1317 	if (!driver_override)
1318 		return -ENOMEM;
1319 
1320 	cp = strchr(driver_override, '\n');
1321 	if (cp)
1322 		*cp = '\0';
1323 
1324 	device_lock(dev);
1325 	old = pdev->driver_override;
1326 	if (strlen(driver_override)) {
1327 		pdev->driver_override = driver_override;
1328 	} else {
1329 		kfree(driver_override);
1330 		pdev->driver_override = NULL;
1331 	}
1332 	device_unlock(dev);
1333 
1334 	kfree(old);
1335 
1336 	return count;
1337 }
1338 static DEVICE_ATTR_RW(driver_override);
1339 
1340 static struct attribute *platform_dev_attrs[] = {
1341 	&dev_attr_modalias.attr,
1342 	&dev_attr_numa_node.attr,
1343 	&dev_attr_driver_override.attr,
1344 	NULL,
1345 };
1346 
1347 static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1348 		int n)
1349 {
1350 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1351 
1352 	if (a == &dev_attr_numa_node.attr &&
1353 			dev_to_node(dev) == NUMA_NO_NODE)
1354 		return 0;
1355 
1356 	return a->mode;
1357 }
1358 
1359 static struct attribute_group platform_dev_group = {
1360 	.attrs = platform_dev_attrs,
1361 	.is_visible = platform_dev_attrs_visible,
1362 };
1363 __ATTRIBUTE_GROUPS(platform_dev);
1364 
1365 
1366 /**
1367  * platform_match - bind platform device to platform driver.
1368  * @dev: device.
1369  * @drv: driver.
1370  *
1371  * Platform device IDs are assumed to be encoded like this:
1372  * "<name><instance>", where <name> is a short description of the type of
1373  * device, like "pci" or "floppy", and <instance> is the enumerated
1374  * instance of the device, like '0' or '42'.  Driver IDs are simply
1375  * "<name>".  So, extract the <name> from the platform_device structure,
1376  * and compare it against the name of the driver. Return whether they match
1377  * or not.
1378  */
1379 static int platform_match(struct device *dev, struct device_driver *drv)
1380 {
1381 	struct platform_device *pdev = to_platform_device(dev);
1382 	struct platform_driver *pdrv = to_platform_driver(drv);
1383 
1384 	/* When driver_override is set, only bind to the matching driver */
1385 	if (pdev->driver_override)
1386 		return !strcmp(pdev->driver_override, drv->name);
1387 
1388 	/* Attempt an OF style match first */
1389 	if (of_driver_match_device(dev, drv))
1390 		return 1;
1391 
1392 	/* Then try ACPI style match */
1393 	if (acpi_driver_match_device(dev, drv))
1394 		return 1;
1395 
1396 	/* Then try to match against the id table */
1397 	if (pdrv->id_table)
1398 		return platform_match_id(pdrv->id_table, pdev) != NULL;
1399 
1400 	/* fall-back to driver name match */
1401 	return (strcmp(pdev->name, drv->name) == 0);
1402 }
1403 
1404 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1405 {
1406 	struct platform_device	*pdev = to_platform_device(dev);
1407 	int rc;
1408 
1409 	/* Some devices have extra OF data and an OF-style MODALIAS */
1410 	rc = of_device_uevent_modalias(dev, env);
1411 	if (rc != -ENODEV)
1412 		return rc;
1413 
1414 	rc = acpi_device_uevent_modalias(dev, env);
1415 	if (rc != -ENODEV)
1416 		return rc;
1417 
1418 	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1419 			pdev->name);
1420 	return 0;
1421 }
1422 
1423 static int platform_probe(struct device *_dev)
1424 {
1425 	struct platform_driver *drv = to_platform_driver(_dev->driver);
1426 	struct platform_device *dev = to_platform_device(_dev);
1427 	int ret;
1428 
1429 	/*
1430 	 * A driver registered using platform_driver_probe() cannot be bound
1431 	 * again later because the probe function usually lives in __init code
1432 	 * and so is gone. For these drivers .probe is set to
1433 	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1434 	 * clocks and PM domains for these to match the traditional behaviour.
1435 	 */
1436 	if (unlikely(drv->probe == platform_probe_fail))
1437 		return -ENXIO;
1438 
1439 	ret = of_clk_set_defaults(_dev->of_node, false);
1440 	if (ret < 0)
1441 		return ret;
1442 
1443 	ret = dev_pm_domain_attach(_dev, true);
1444 	if (ret)
1445 		goto out;
1446 
1447 	if (drv->probe) {
1448 		ret = drv->probe(dev);
1449 		if (ret)
1450 			dev_pm_domain_detach(_dev, true);
1451 	}
1452 
1453 out:
1454 	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1455 		dev_warn(_dev, "probe deferral not supported\n");
1456 		ret = -ENXIO;
1457 	}
1458 
1459 	return ret;
1460 }
1461 
1462 static int platform_remove(struct device *_dev)
1463 {
1464 	struct platform_driver *drv = to_platform_driver(_dev->driver);
1465 	struct platform_device *dev = to_platform_device(_dev);
1466 
1467 	if (drv->remove) {
1468 		int ret = drv->remove(dev);
1469 
1470 		if (ret)
1471 			dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1472 	}
1473 	dev_pm_domain_detach(_dev, true);
1474 
1475 	return 0;
1476 }
1477 
1478 static void platform_shutdown(struct device *_dev)
1479 {
1480 	struct platform_device *dev = to_platform_device(_dev);
1481 	struct platform_driver *drv;
1482 
1483 	if (!_dev->driver)
1484 		return;
1485 
1486 	drv = to_platform_driver(_dev->driver);
1487 	if (drv->shutdown)
1488 		drv->shutdown(dev);
1489 }
1490 
1491 
1492 int platform_dma_configure(struct device *dev)
1493 {
1494 	enum dev_dma_attr attr;
1495 	int ret = 0;
1496 
1497 	if (dev->of_node) {
1498 		ret = of_dma_configure(dev, dev->of_node, true);
1499 	} else if (has_acpi_companion(dev)) {
1500 		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1501 		ret = acpi_dma_configure(dev, attr);
1502 	}
1503 
1504 	return ret;
1505 }
1506 
1507 static const struct dev_pm_ops platform_dev_pm_ops = {
1508 	.runtime_suspend = pm_generic_runtime_suspend,
1509 	.runtime_resume = pm_generic_runtime_resume,
1510 	USE_PLATFORM_PM_SLEEP_OPS
1511 };
1512 
1513 struct bus_type platform_bus_type = {
1514 	.name		= "platform",
1515 	.dev_groups	= platform_dev_groups,
1516 	.match		= platform_match,
1517 	.uevent		= platform_uevent,
1518 	.probe		= platform_probe,
1519 	.remove		= platform_remove,
1520 	.shutdown	= platform_shutdown,
1521 	.dma_configure	= platform_dma_configure,
1522 	.pm		= &platform_dev_pm_ops,
1523 };
1524 EXPORT_SYMBOL_GPL(platform_bus_type);
1525 
1526 static inline int __platform_match(struct device *dev, const void *drv)
1527 {
1528 	return platform_match(dev, (struct device_driver *)drv);
1529 }
1530 
1531 /**
1532  * platform_find_device_by_driver - Find a platform device with a given
1533  * driver.
1534  * @start: The device to start the search from.
1535  * @drv: The device driver to look for.
1536  */
1537 struct device *platform_find_device_by_driver(struct device *start,
1538 					      const struct device_driver *drv)
1539 {
1540 	return bus_find_device(&platform_bus_type, start, drv,
1541 			       __platform_match);
1542 }
1543 EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1544 
1545 void __weak __init early_platform_cleanup(void) { }
1546 
1547 int __init platform_bus_init(void)
1548 {
1549 	int error;
1550 
1551 	early_platform_cleanup();
1552 
1553 	error = device_register(&platform_bus);
1554 	if (error) {
1555 		put_device(&platform_bus);
1556 		return error;
1557 	}
1558 	error =  bus_register(&platform_bus_type);
1559 	if (error)
1560 		device_unregister(&platform_bus);
1561 	of_platform_register_reconfig_notifier();
1562 	return error;
1563 }
1564