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