xref: /linux/drivers/base/platform.c (revision 4793dae01f47754e288cdbb3a22581cac2317f2b)
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 #include <linux/iommu.h>
34 #include <linux/dma-map-ops.h>
35 
36 #include "base.h"
37 #include "power/power.h"
38 
39 /* For automatically allocated device IDs */
40 static DEFINE_IDA(platform_devid_ida);
41 
42 struct device platform_bus = {
43 	.init_name	= "platform",
44 };
45 EXPORT_SYMBOL_GPL(platform_bus);
46 
47 /**
48  * platform_get_resource - get a resource for a device
49  * @dev: platform device
50  * @type: resource type
51  * @num: resource index
52  *
53  * Return: a pointer to the resource or NULL on failure.
54  */
platform_get_resource(struct platform_device * dev,unsigned int type,unsigned int num)55 struct resource *platform_get_resource(struct platform_device *dev,
56 				       unsigned int type, unsigned int num)
57 {
58 	u32 i;
59 
60 	for (i = 0; i < dev->num_resources; i++) {
61 		struct resource *r = &dev->resource[i];
62 
63 		if (type == resource_type(r) && num-- == 0)
64 			return r;
65 	}
66 	return NULL;
67 }
68 EXPORT_SYMBOL_GPL(platform_get_resource);
69 
platform_get_mem_or_io(struct platform_device * dev,unsigned int num)70 struct resource *platform_get_mem_or_io(struct platform_device *dev,
71 					unsigned int num)
72 {
73 	u32 i;
74 
75 	for (i = 0; i < dev->num_resources; i++) {
76 		struct resource *r = &dev->resource[i];
77 
78 		if ((resource_type(r) & (IORESOURCE_MEM | IORESOURCE_IO)) && num-- == 0)
79 			return r;
80 	}
81 	return NULL;
82 }
83 EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
84 
85 #ifdef CONFIG_HAS_IOMEM
86 /**
87  * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
88  *					    platform device and get resource
89  *
90  * @pdev: platform device to use both for memory resource lookup as well as
91  *        resource management
92  * @index: resource index
93  * @res: optional output parameter to store a pointer to the obtained resource.
94  *
95  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
96  * on failure.
97  */
98 void __iomem *
devm_platform_get_and_ioremap_resource(struct platform_device * pdev,unsigned int index,struct resource ** res)99 devm_platform_get_and_ioremap_resource(struct platform_device *pdev,
100 				       unsigned int index, struct resource **res)
101 {
102 	struct resource *r;
103 
104 	r = platform_get_resource(pdev, IORESOURCE_MEM, index);
105 	if (res)
106 		*res = r;
107 	return devm_ioremap_resource(&pdev->dev, r);
108 }
109 EXPORT_SYMBOL_GPL(devm_platform_get_and_ioremap_resource);
110 
111 /**
112  * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
113  *				    device
114  *
115  * @pdev: platform device to use both for memory resource lookup as well as
116  *        resource management
117  * @index: resource index
118  *
119  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
120  * on failure.
121  */
devm_platform_ioremap_resource(struct platform_device * pdev,unsigned int index)122 void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
123 					     unsigned int index)
124 {
125 	return devm_platform_get_and_ioremap_resource(pdev, index, NULL);
126 }
127 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
128 
129 /**
130  * devm_platform_ioremap_resource_byname - call devm_ioremap_resource for
131  *					   a platform device, retrieve the
132  *					   resource by name
133  *
134  * @pdev: platform device to use both for memory resource lookup as well as
135  *	  resource management
136  * @name: name of the resource
137  *
138  * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
139  * on failure.
140  */
141 void __iomem *
devm_platform_ioremap_resource_byname(struct platform_device * pdev,const char * name)142 devm_platform_ioremap_resource_byname(struct platform_device *pdev,
143 				      const char *name)
144 {
145 	struct resource *res;
146 
147 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
148 	return devm_ioremap_resource(&pdev->dev, res);
149 }
150 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
151 #endif /* CONFIG_HAS_IOMEM */
152 
get_irq_affinity(struct platform_device * dev,unsigned int num)153 static const struct cpumask *get_irq_affinity(struct platform_device *dev,
154 					      unsigned int num)
155 {
156 	const struct cpumask *mask = NULL;
157 #ifndef CONFIG_SPARC
158 	struct fwnode_handle *fwnode = dev_fwnode(&dev->dev);
159 
160 	if (is_of_node(fwnode))
161 		mask = of_irq_get_affinity(to_of_node(fwnode), num);
162 	else if (is_acpi_device_node(fwnode))
163 		mask = acpi_irq_get_affinity(ACPI_HANDLE_FWNODE(fwnode), num);
164 #endif
165 
166 	return mask ?: cpu_possible_mask;
167 }
168 
169 /**
170  * platform_get_irq_affinity - get an optional IRQ and its affinity for a device
171  * @dev:	platform device
172  * @num:	interrupt number index
173  * @affinity:	optional cpumask pointer to get the affinity of a per-cpu interrupt
174  *
175  * Gets an interrupt for a platform device. Device drivers should check the
176  * return value for errors so as to not pass a negative integer value to
177  * the request_irq() APIs. Optional affinity information is provided in the
178  * affinity pointer if available, and NULL otherwise.
179  *
180  * Return: non-zero interrupt number on success, negative error number on failure.
181  */
platform_get_irq_affinity(struct platform_device * dev,unsigned int num,const struct cpumask ** affinity)182 int platform_get_irq_affinity(struct platform_device *dev, unsigned int num,
183 			      const struct cpumask **affinity)
184 {
185 	int ret;
186 #ifdef CONFIG_SPARC
187 	/* sparc does not have irqs represented as IORESOURCE_IRQ resources */
188 	if (!dev || num >= dev->archdata.num_irqs)
189 		goto out_not_found;
190 	ret = dev->archdata.irqs[num];
191 	goto out;
192 #else
193 	struct fwnode_handle *fwnode = dev_fwnode(&dev->dev);
194 	struct resource *r;
195 
196 	if (is_of_node(fwnode)) {
197 		ret = of_irq_get(to_of_node(fwnode), num);
198 		if (ret > 0 || ret == -EPROBE_DEFER)
199 			goto out;
200 	}
201 
202 	r = platform_get_resource(dev, IORESOURCE_IRQ, num);
203 	if (is_acpi_device_node(fwnode)) {
204 		if (r && r->flags & IORESOURCE_DISABLED) {
205 			ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), num, r);
206 			if (ret)
207 				goto out;
208 		}
209 	}
210 
211 	/*
212 	 * The resources may pass trigger flags to the irqs that need
213 	 * to be set up. It so happens that the trigger flags for
214 	 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
215 	 * settings.
216 	 */
217 	if (r && r->flags & IORESOURCE_BITS) {
218 		struct irq_data *irqd;
219 
220 		irqd = irq_get_irq_data(r->start);
221 		if (!irqd)
222 			goto out_not_found;
223 		irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
224 	}
225 
226 	if (r) {
227 		ret = r->start;
228 		goto out;
229 	}
230 
231 	/*
232 	 * For the index 0 interrupt, allow falling back to GpioInt
233 	 * resources. While a device could have both Interrupt and GpioInt
234 	 * resources, making this fallback ambiguous, in many common cases
235 	 * the device will only expose one IRQ, and this fallback
236 	 * allows a common code path across either kind of resource.
237 	 */
238 	if (num == 0 && is_acpi_device_node(fwnode)) {
239 		ret = acpi_dev_gpio_irq_get(to_acpi_device_node(fwnode), num);
240 		/* Our callers expect -ENXIO for missing IRQs. */
241 		if (ret >= 0 || ret == -EPROBE_DEFER)
242 			goto out;
243 	}
244 
245 #endif
246 out_not_found:
247 	ret = -ENXIO;
248 out:
249 	if (WARN(!ret, "0 is an invalid IRQ number\n"))
250 		return -EINVAL;
251 
252 	if (ret > 0 && affinity)
253 		*affinity = get_irq_affinity(dev, num);
254 
255 	return ret;
256 }
257 EXPORT_SYMBOL_GPL(platform_get_irq_affinity);
258 
259 /**
260  * platform_get_irq_optional - get an optional interrupt for a device
261  * @dev:	platform device
262  * @num:	interrupt number index
263  *
264  * Gets an interrupt for a platform device. Device drivers should check the
265  * return value for errors so as to not pass a negative integer value to
266  * the request_irq() APIs. This is the same as platform_get_irq(), except
267  * that it does not print an error message if an interrupt can not be
268  * obtained.
269  *
270  * For example::
271  *
272  *		int irq = platform_get_irq_optional(pdev, 0);
273  *		if (irq < 0)
274  *			return irq;
275  *
276  * Return: non-zero interrupt number on success, negative error number on failure.
277  */
platform_get_irq_optional(struct platform_device * dev,unsigned int num)278 int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
279 {
280 	return platform_get_irq_affinity(dev, num, NULL);
281 }
282 EXPORT_SYMBOL_GPL(platform_get_irq_optional);
283 
284 /**
285  * platform_get_irq - get an IRQ for a device
286  * @dev: platform device
287  * @num: IRQ number index
288  *
289  * Gets an IRQ for a platform device and prints an error message if finding the
290  * IRQ fails. Device drivers should check the return value for errors so as to
291  * not pass a negative integer value to the request_irq() APIs.
292  *
293  * For example::
294  *
295  *		int irq = platform_get_irq(pdev, 0);
296  *		if (irq < 0)
297  *			return irq;
298  *
299  * Return: non-zero IRQ number on success, negative error number on failure.
300  */
platform_get_irq(struct platform_device * dev,unsigned int num)301 int platform_get_irq(struct platform_device *dev, unsigned int num)
302 {
303 	int ret;
304 
305 	ret = platform_get_irq_optional(dev, num);
306 	if (ret < 0)
307 		return dev_err_probe(&dev->dev, ret,
308 				     "IRQ index %u not found\n", num);
309 
310 	return ret;
311 }
312 EXPORT_SYMBOL_GPL(platform_get_irq);
313 
314 /**
315  * platform_irq_count - Count the number of IRQs a platform device uses
316  * @dev: platform device
317  *
318  * Return: Number of IRQs a platform device uses or EPROBE_DEFER
319  */
platform_irq_count(struct platform_device * dev)320 int platform_irq_count(struct platform_device *dev)
321 {
322 	int ret, nr = 0;
323 
324 	while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
325 		nr++;
326 
327 	if (ret == -EPROBE_DEFER)
328 		return ret;
329 
330 	return nr;
331 }
332 EXPORT_SYMBOL_GPL(platform_irq_count);
333 
334 struct irq_affinity_devres {
335 	unsigned int count;
336 	unsigned int irq[] __counted_by(count);
337 };
338 
platform_disable_acpi_irq(struct platform_device * pdev,int index)339 static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
340 {
341 	struct resource *r;
342 
343 	r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
344 	if (r)
345 		irqresource_disabled(r, 0);
346 }
347 
devm_platform_get_irqs_affinity_release(struct device * dev,void * res)348 static void devm_platform_get_irqs_affinity_release(struct device *dev,
349 						    void *res)
350 {
351 	struct irq_affinity_devres *ptr = res;
352 	int i;
353 
354 	for (i = 0; i < ptr->count; i++) {
355 		irq_dispose_mapping(ptr->irq[i]);
356 
357 		if (is_acpi_device_node(dev_fwnode(dev)))
358 			platform_disable_acpi_irq(to_platform_device(dev), i);
359 	}
360 }
361 
362 /**
363  * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
364  *				device using an interrupt affinity descriptor
365  * @dev: platform device pointer
366  * @affd: affinity descriptor
367  * @minvec: minimum count of interrupt vectors
368  * @maxvec: maximum count of interrupt vectors
369  * @irqs: pointer holder for IRQ numbers
370  *
371  * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
372  * to the passed affinity descriptor
373  *
374  * Return: Number of vectors on success, negative error number on failure.
375  */
devm_platform_get_irqs_affinity(struct platform_device * dev,struct irq_affinity * affd,unsigned int minvec,unsigned int maxvec,int ** irqs)376 int devm_platform_get_irqs_affinity(struct platform_device *dev,
377 				    struct irq_affinity *affd,
378 				    unsigned int minvec,
379 				    unsigned int maxvec,
380 				    int **irqs)
381 {
382 	struct irq_affinity_devres *ptr;
383 	struct irq_affinity_desc *desc;
384 	size_t size;
385 	int i, ret, nvec;
386 
387 	if (!affd)
388 		return -EPERM;
389 
390 	if (maxvec < minvec)
391 		return -ERANGE;
392 
393 	nvec = platform_irq_count(dev);
394 	if (nvec < 0)
395 		return nvec;
396 
397 	if (nvec < minvec)
398 		return -ENOSPC;
399 
400 	nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
401 	if (nvec < minvec)
402 		return -ENOSPC;
403 
404 	if (nvec > maxvec)
405 		nvec = maxvec;
406 
407 	size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
408 	ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
409 			   GFP_KERNEL);
410 	if (!ptr)
411 		return -ENOMEM;
412 
413 	ptr->count = nvec;
414 
415 	for (i = 0; i < nvec; i++) {
416 		int irq = platform_get_irq(dev, i);
417 		if (irq < 0) {
418 			ret = irq;
419 			goto err_free_devres;
420 		}
421 		ptr->irq[i] = irq;
422 	}
423 
424 	desc = irq_create_affinity_masks(nvec, affd);
425 	if (!desc) {
426 		ret = -ENOMEM;
427 		goto err_free_devres;
428 	}
429 
430 	for (i = 0; i < nvec; i++) {
431 		ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
432 		if (ret) {
433 			dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
434 				ptr->irq[i], ret);
435 			goto err_free_desc;
436 		}
437 	}
438 
439 	devres_add(&dev->dev, ptr);
440 
441 	kfree(desc);
442 
443 	*irqs = ptr->irq;
444 
445 	return nvec;
446 
447 err_free_desc:
448 	kfree(desc);
449 err_free_devres:
450 	devres_free(ptr);
451 	return ret;
452 }
453 EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
454 
455 /**
456  * platform_get_resource_byname - get a resource for a device by name
457  * @dev: platform device
458  * @type: resource type
459  * @name: resource name
460  */
platform_get_resource_byname(struct platform_device * dev,unsigned int type,const char * name)461 struct resource *platform_get_resource_byname(struct platform_device *dev,
462 					      unsigned int type,
463 					      const char *name)
464 {
465 	u32 i;
466 
467 	for (i = 0; i < dev->num_resources; i++) {
468 		struct resource *r = &dev->resource[i];
469 
470 		if (unlikely(!r->name))
471 			continue;
472 
473 		if (type == resource_type(r) && !strcmp(r->name, name))
474 			return r;
475 	}
476 	return NULL;
477 }
478 EXPORT_SYMBOL_GPL(platform_get_resource_byname);
479 
__platform_get_irq_byname(struct platform_device * dev,const char * name)480 static int __platform_get_irq_byname(struct platform_device *dev,
481 				     const char *name)
482 {
483 	struct resource *r;
484 	int ret;
485 
486 	ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
487 	if (ret > 0 || ret == -EPROBE_DEFER)
488 		return ret;
489 
490 	r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
491 	if (r) {
492 		if (WARN(!r->start, "0 is an invalid IRQ number\n"))
493 			return -EINVAL;
494 		return r->start;
495 	}
496 
497 	return -ENXIO;
498 }
499 
500 /**
501  * platform_get_irq_byname - get an IRQ for a device by name
502  * @dev: platform device
503  * @name: IRQ name
504  *
505  * Get an IRQ like platform_get_irq(), but then by name rather then by index.
506  *
507  * Return: non-zero IRQ number on success, negative error number on failure.
508  */
platform_get_irq_byname(struct platform_device * dev,const char * name)509 int platform_get_irq_byname(struct platform_device *dev, const char *name)
510 {
511 	int ret;
512 
513 	ret = __platform_get_irq_byname(dev, name);
514 	if (ret < 0)
515 		return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
516 				     name);
517 	return ret;
518 }
519 EXPORT_SYMBOL_GPL(platform_get_irq_byname);
520 
521 /**
522  * platform_get_irq_byname_optional - get an optional IRQ for a device by name
523  * @dev: platform device
524  * @name: IRQ name
525  *
526  * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
527  * does not print an error message if an IRQ can not be obtained.
528  *
529  * Return: non-zero IRQ number on success, negative error number on failure.
530  */
platform_get_irq_byname_optional(struct platform_device * dev,const char * name)531 int platform_get_irq_byname_optional(struct platform_device *dev,
532 				     const char *name)
533 {
534 	return __platform_get_irq_byname(dev, name);
535 }
536 EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
537 
538 /**
539  * platform_add_devices - add a numbers of platform devices
540  * @devs: array of platform devices to add
541  * @num: number of platform devices in array
542  *
543  * Return: 0 on success, negative error number on failure.
544  */
platform_add_devices(struct platform_device ** devs,int num)545 int platform_add_devices(struct platform_device **devs, int num)
546 {
547 	int i, ret = 0;
548 
549 	for (i = 0; i < num; i++) {
550 		ret = platform_device_register(devs[i]);
551 		if (ret) {
552 			while (--i >= 0)
553 				platform_device_unregister(devs[i]);
554 			break;
555 		}
556 	}
557 
558 	return ret;
559 }
560 EXPORT_SYMBOL_GPL(platform_add_devices);
561 
562 struct platform_object {
563 	struct platform_device pdev;
564 	char name[];
565 };
566 
567 /*
568  * Set up default DMA mask for platform devices if the they weren't
569  * previously set by the architecture / DT.
570  */
setup_pdev_dma_masks(struct platform_device * pdev)571 static void setup_pdev_dma_masks(struct platform_device *pdev)
572 {
573 	pdev->dev.dma_parms = &pdev->dma_parms;
574 
575 	if (!pdev->dev.coherent_dma_mask)
576 		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
577 	if (!pdev->dev.dma_mask) {
578 		pdev->platform_dma_mask = DMA_BIT_MASK(32);
579 		pdev->dev.dma_mask = &pdev->platform_dma_mask;
580 	}
581 };
582 
583 /**
584  * platform_device_put - destroy a platform device
585  * @pdev: platform device to free
586  *
587  * Free all memory associated with a platform device.  This function must
588  * _only_ be externally called in error cases.  All other usage is a bug.
589  */
platform_device_put(struct platform_device * pdev)590 void platform_device_put(struct platform_device *pdev)
591 {
592 	if (!IS_ERR_OR_NULL(pdev))
593 		put_device(&pdev->dev);
594 }
595 EXPORT_SYMBOL_GPL(platform_device_put);
596 
platform_device_release(struct device * dev)597 static void platform_device_release(struct device *dev)
598 {
599 	struct platform_object *pa = container_of(dev, struct platform_object,
600 						  pdev.dev);
601 
602 	of_node_put(pa->pdev.dev.of_node);
603 	kfree(pa->pdev.dev.platform_data);
604 	kfree(pa->pdev.mfd_cell);
605 	kfree(pa->pdev.resource);
606 	kfree(pa);
607 }
608 
609 /**
610  * platform_device_alloc - create a platform device
611  * @name: base name of the device we're adding
612  * @id: instance id
613  *
614  * Create a platform device object which can have other objects attached
615  * to it, and which will have attached objects freed when it is released.
616  */
platform_device_alloc(const char * name,int id)617 struct platform_device *platform_device_alloc(const char *name, int id)
618 {
619 	struct platform_object *pa;
620 
621 	pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
622 	if (pa) {
623 		strcpy(pa->name, name);
624 		pa->pdev.name = pa->name;
625 		pa->pdev.id = id;
626 		device_initialize(&pa->pdev.dev);
627 		pa->pdev.dev.release = platform_device_release;
628 		setup_pdev_dma_masks(&pa->pdev);
629 	}
630 
631 	return pa ? &pa->pdev : NULL;
632 }
633 EXPORT_SYMBOL_GPL(platform_device_alloc);
634 
635 /**
636  * platform_device_add_resources - add resources to a platform device
637  * @pdev: platform device allocated by platform_device_alloc to add resources to
638  * @res: set of resources that needs to be allocated for the device
639  * @num: number of resources
640  *
641  * Add a copy of the resources to the platform device.  The memory
642  * associated with the resources will be freed when the platform device is
643  * released.
644  */
platform_device_add_resources(struct platform_device * pdev,const struct resource * res,unsigned int num)645 int platform_device_add_resources(struct platform_device *pdev,
646 				  const struct resource *res, unsigned int num)
647 {
648 	struct resource *r = NULL;
649 
650 	if (res) {
651 		r = kmemdup_array(res, num, sizeof(*r), GFP_KERNEL);
652 		if (!r)
653 			return -ENOMEM;
654 	}
655 
656 	kfree(pdev->resource);
657 	pdev->resource = r;
658 	pdev->num_resources = num;
659 	return 0;
660 }
661 EXPORT_SYMBOL_GPL(platform_device_add_resources);
662 
663 /**
664  * platform_device_add_data - add platform-specific data to a platform device
665  * @pdev: platform device allocated by platform_device_alloc to add resources to
666  * @data: platform specific data for this platform device
667  * @size: size of platform specific data
668  *
669  * Add a copy of platform specific data to the platform device's
670  * platform_data pointer.  The memory associated with the platform data
671  * will be freed when the platform device is released.
672  */
platform_device_add_data(struct platform_device * pdev,const void * data,size_t size)673 int platform_device_add_data(struct platform_device *pdev, const void *data,
674 			     size_t size)
675 {
676 	void *d = NULL;
677 
678 	if (data) {
679 		d = kmemdup(data, size, GFP_KERNEL);
680 		if (!d)
681 			return -ENOMEM;
682 	}
683 
684 	kfree(pdev->dev.platform_data);
685 	pdev->dev.platform_data = d;
686 	return 0;
687 }
688 EXPORT_SYMBOL_GPL(platform_device_add_data);
689 
690 /**
691  * platform_device_add - add a platform device to device hierarchy
692  * @pdev: platform device we're adding
693  *
694  * This is part 2 of platform_device_register(), though may be called
695  * separately _iff_ pdev was allocated by platform_device_alloc().
696  */
platform_device_add(struct platform_device * pdev)697 int platform_device_add(struct platform_device *pdev)
698 {
699 	struct device *dev = &pdev->dev;
700 	u32 i;
701 	int ret;
702 
703 	if (!dev->parent)
704 		dev->parent = &platform_bus;
705 
706 	dev->bus = &platform_bus_type;
707 
708 	switch (pdev->id) {
709 	default:
710 		dev_set_name(dev, "%s.%d", pdev->name,  pdev->id);
711 		break;
712 	case PLATFORM_DEVID_NONE:
713 		dev_set_name(dev, "%s", pdev->name);
714 		break;
715 	case PLATFORM_DEVID_AUTO:
716 		/*
717 		 * Automatically allocated device ID. We mark it as such so
718 		 * that we remember it must be freed, and we append a suffix
719 		 * to avoid namespace collision with explicit IDs.
720 		 */
721 		ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
722 		if (ret < 0)
723 			return ret;
724 		pdev->id = ret;
725 		pdev->id_auto = true;
726 		dev_set_name(dev, "%s.%d.auto", pdev->name, pdev->id);
727 		break;
728 	}
729 
730 	for (i = 0; i < pdev->num_resources; i++) {
731 		struct resource *p, *r = &pdev->resource[i];
732 
733 		if (r->name == NULL)
734 			r->name = dev_name(dev);
735 
736 		p = r->parent;
737 		if (!p) {
738 			if (resource_type(r) == IORESOURCE_MEM)
739 				p = &iomem_resource;
740 			else if (resource_type(r) == IORESOURCE_IO)
741 				p = &ioport_resource;
742 		}
743 
744 		if (p) {
745 			ret = insert_resource(p, r);
746 			if (ret) {
747 				dev_err(dev, "failed to claim resource %d: %pR\n", i, r);
748 				goto failed;
749 			}
750 		}
751 	}
752 
753 	pr_debug("Registering platform device '%s'. Parent at %s\n", dev_name(dev),
754 		 dev_name(dev->parent));
755 
756 	ret = device_add(dev);
757 	if (ret)
758 		goto failed;
759 
760 	return 0;
761 
762  failed:
763 	if (pdev->id_auto) {
764 		ida_free(&platform_devid_ida, pdev->id);
765 		pdev->id = PLATFORM_DEVID_AUTO;
766 	}
767 
768 	while (i--) {
769 		struct resource *r = &pdev->resource[i];
770 		if (r->parent)
771 			release_resource(r);
772 	}
773 
774 	return ret;
775 }
776 EXPORT_SYMBOL_GPL(platform_device_add);
777 
778 /**
779  * platform_device_del - remove a platform-level device
780  * @pdev: platform device we're removing
781  *
782  * Note that this function will also release all memory- and port-based
783  * resources owned by the device (@dev->resource).  This function must
784  * _only_ be externally called in error cases.  All other usage is a bug.
785  */
platform_device_del(struct platform_device * pdev)786 void platform_device_del(struct platform_device *pdev)
787 {
788 	u32 i;
789 
790 	if (!IS_ERR_OR_NULL(pdev)) {
791 		device_del(&pdev->dev);
792 
793 		if (pdev->id_auto) {
794 			ida_free(&platform_devid_ida, pdev->id);
795 			pdev->id = PLATFORM_DEVID_AUTO;
796 		}
797 
798 		for (i = 0; i < pdev->num_resources; i++) {
799 			struct resource *r = &pdev->resource[i];
800 			if (r->parent)
801 				release_resource(r);
802 		}
803 	}
804 }
805 EXPORT_SYMBOL_GPL(platform_device_del);
806 
807 /**
808  * platform_device_register - add a platform-level device
809  * @pdev: platform device we're adding
810  *
811  * NOTE: _Never_ directly free @pdev after calling this function, even if it
812  * returned an error! Always use platform_device_put() to give up the
813  * reference initialised in this function instead.
814  */
platform_device_register(struct platform_device * pdev)815 int platform_device_register(struct platform_device *pdev)
816 {
817 	device_initialize(&pdev->dev);
818 	setup_pdev_dma_masks(pdev);
819 	return platform_device_add(pdev);
820 }
821 EXPORT_SYMBOL_GPL(platform_device_register);
822 
823 /**
824  * platform_device_unregister - unregister a platform-level device
825  * @pdev: platform device we're unregistering
826  *
827  * Unregistration is done in 2 steps. First we release all resources
828  * and remove it from the subsystem, then we drop reference count by
829  * calling platform_device_put().
830  */
platform_device_unregister(struct platform_device * pdev)831 void platform_device_unregister(struct platform_device *pdev)
832 {
833 	platform_device_del(pdev);
834 	platform_device_put(pdev);
835 }
836 EXPORT_SYMBOL_GPL(platform_device_unregister);
837 
838 /**
839  * platform_device_register_full - add a platform-level device with
840  * resources and platform-specific data
841  *
842  * @pdevinfo: data used to create device
843  *
844  * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
845  */
platform_device_register_full(const struct platform_device_info * pdevinfo)846 struct platform_device *platform_device_register_full(const struct platform_device_info *pdevinfo)
847 {
848 	int ret;
849 	struct platform_device *pdev;
850 
851 	if (pdevinfo->swnode && pdevinfo->properties)
852 		return ERR_PTR(-EINVAL);
853 
854 	pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
855 	if (!pdev)
856 		return ERR_PTR(-ENOMEM);
857 
858 	pdev->dev.parent = pdevinfo->parent;
859 	pdev->dev.fwnode = pdevinfo->fwnode;
860 	pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
861 	pdev->dev.of_node_reused = pdevinfo->of_node_reused;
862 
863 	if (pdevinfo->dma_mask) {
864 		pdev->platform_dma_mask = pdevinfo->dma_mask;
865 		pdev->dev.dma_mask = &pdev->platform_dma_mask;
866 		pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
867 	}
868 
869 	ret = platform_device_add_resources(pdev, pdevinfo->res, pdevinfo->num_res);
870 	if (ret)
871 		goto err;
872 
873 	ret = platform_device_add_data(pdev, pdevinfo->data, pdevinfo->size_data);
874 	if (ret)
875 		goto err;
876 
877 	if (pdevinfo->swnode) {
878 		ret = device_add_software_node(&pdev->dev, pdevinfo->swnode);
879 		if (ret)
880 			goto err;
881 	} else if (pdevinfo->properties) {
882 		ret = device_create_managed_software_node(&pdev->dev,
883 							  pdevinfo->properties, NULL);
884 		if (ret)
885 			goto err;
886 	}
887 
888 	ret = platform_device_add(pdev);
889 	if (ret) {
890 err:
891 		ACPI_COMPANION_SET(&pdev->dev, NULL);
892 		platform_device_put(pdev);
893 		return ERR_PTR(ret);
894 	}
895 
896 	return pdev;
897 }
898 EXPORT_SYMBOL_GPL(platform_device_register_full);
899 
900 /**
901  * __platform_driver_register - register a driver for platform-level devices
902  * @drv: platform driver structure
903  * @owner: owning module/driver
904  */
__platform_driver_register(struct platform_driver * drv,struct module * owner)905 int __platform_driver_register(struct platform_driver *drv, struct module *owner)
906 {
907 	drv->driver.owner = owner;
908 	drv->driver.bus = &platform_bus_type;
909 
910 	return driver_register(&drv->driver);
911 }
912 EXPORT_SYMBOL_GPL(__platform_driver_register);
913 
914 /**
915  * platform_driver_unregister - unregister a driver for platform-level devices
916  * @drv: platform driver structure
917  */
platform_driver_unregister(struct platform_driver * drv)918 void platform_driver_unregister(struct platform_driver *drv)
919 {
920 	driver_unregister(&drv->driver);
921 }
922 EXPORT_SYMBOL_GPL(platform_driver_unregister);
923 
platform_probe_fail(struct platform_device * pdev)924 static int platform_probe_fail(struct platform_device *pdev)
925 {
926 	return -ENXIO;
927 }
928 
is_bound_to_driver(struct device * dev,void * driver)929 static int is_bound_to_driver(struct device *dev, void *driver)
930 {
931 	if (dev->driver == driver)
932 		return 1;
933 	return 0;
934 }
935 
936 /**
937  * __platform_driver_probe - register driver for non-hotpluggable device
938  * @drv: platform driver structure
939  * @probe: the driver probe routine, probably from an __init section
940  * @module: module which will be the owner of the driver
941  *
942  * Use this instead of platform_driver_register() when you know the device
943  * is not hotpluggable and has already been registered, and you want to
944  * remove its run-once probe() infrastructure from memory after the driver
945  * has bound to the device.
946  *
947  * One typical use for this would be with drivers for controllers integrated
948  * into system-on-chip processors, where the controller devices have been
949  * configured as part of board setup.
950  *
951  * Note that this is incompatible with deferred probing.
952  *
953  * Returns zero if the driver registered and bound to a device, else returns
954  * a negative error code and with the driver not registered.
955  */
__platform_driver_probe(struct platform_driver * drv,int (* probe)(struct platform_device *),struct module * module)956 int __init_or_module __platform_driver_probe(struct platform_driver *drv,
957 					     int (*probe)(struct platform_device *),
958 					     struct module *module)
959 {
960 	int retval;
961 
962 	if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
963 		pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
964 		       drv->driver.name, __func__);
965 		return -EINVAL;
966 	}
967 
968 	/*
969 	 * We have to run our probes synchronously because we check if
970 	 * we find any devices to bind to and exit with error if there
971 	 * are any.
972 	 */
973 	drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
974 
975 	/*
976 	 * Prevent driver from requesting probe deferral to avoid further
977 	 * futile probe attempts.
978 	 */
979 	drv->prevent_deferred_probe = true;
980 
981 	/* make sure driver won't have bind/unbind attributes */
982 	drv->driver.suppress_bind_attrs = true;
983 
984 	/* temporary section violation during probe() */
985 	drv->probe = probe;
986 	retval = __platform_driver_register(drv, module);
987 	if (retval)
988 		return retval;
989 
990 	/* Force all new probes of this driver to fail */
991 	drv->probe = platform_probe_fail;
992 
993 	/* Walk all platform devices and see if any actually bound to this driver.
994 	 * If not, return an error as the device should have done so by now.
995 	 */
996 	if (!bus_for_each_dev(&platform_bus_type, NULL, &drv->driver, is_bound_to_driver)) {
997 		retval = -ENODEV;
998 		platform_driver_unregister(drv);
999 	}
1000 
1001 	return retval;
1002 }
1003 EXPORT_SYMBOL_GPL(__platform_driver_probe);
1004 
1005 /**
1006  * __platform_create_bundle - register driver and create corresponding device
1007  * @driver: platform driver structure
1008  * @probe: the driver probe routine, probably from an __init section
1009  * @res: set of resources that needs to be allocated for the device
1010  * @n_res: number of resources
1011  * @data: platform specific data for this platform device
1012  * @size: size of platform specific data
1013  * @module: module which will be the owner of the driver
1014  *
1015  * Use this in legacy-style modules that probe hardware directly and
1016  * register a single platform device and corresponding platform driver.
1017  *
1018  * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
1019  */
1020 struct platform_device * __init_or_module
__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)1021 __platform_create_bundle(struct platform_driver *driver,
1022 			 int (*probe)(struct platform_device *),
1023 			 struct resource *res, unsigned int n_res,
1024 			 const void *data, size_t size, struct module *module)
1025 {
1026 	struct platform_device *pdev;
1027 	int error;
1028 
1029 	pdev = platform_device_alloc(driver->driver.name, PLATFORM_DEVID_NONE);
1030 	if (!pdev) {
1031 		error = -ENOMEM;
1032 		goto err_out;
1033 	}
1034 
1035 	error = platform_device_add_resources(pdev, res, n_res);
1036 	if (error)
1037 		goto err_pdev_put;
1038 
1039 	error = platform_device_add_data(pdev, data, size);
1040 	if (error)
1041 		goto err_pdev_put;
1042 
1043 	error = platform_device_add(pdev);
1044 	if (error)
1045 		goto err_pdev_put;
1046 
1047 	error = __platform_driver_probe(driver, probe, module);
1048 	if (error)
1049 		goto err_pdev_del;
1050 
1051 	return pdev;
1052 
1053 err_pdev_del:
1054 	platform_device_del(pdev);
1055 err_pdev_put:
1056 	platform_device_put(pdev);
1057 err_out:
1058 	return ERR_PTR(error);
1059 }
1060 EXPORT_SYMBOL_GPL(__platform_create_bundle);
1061 
1062 /**
1063  * __platform_register_drivers - register an array of platform drivers
1064  * @drivers: an array of drivers to register
1065  * @count: the number of drivers to register
1066  * @owner: module owning the drivers
1067  *
1068  * Registers platform drivers specified by an array. On failure to register a
1069  * driver, all previously registered drivers will be unregistered. Callers of
1070  * this API should use platform_unregister_drivers() to unregister drivers in
1071  * the reverse order.
1072  *
1073  * Returns: 0 on success or a negative error code on failure.
1074  */
__platform_register_drivers(struct platform_driver * const * drivers,unsigned int count,struct module * owner)1075 int __platform_register_drivers(struct platform_driver * const *drivers,
1076 				unsigned int count, struct module *owner)
1077 {
1078 	unsigned int i;
1079 	int err;
1080 
1081 	for (i = 0; i < count; i++) {
1082 		pr_debug("registering platform driver %ps\n", drivers[i]);
1083 
1084 		err = __platform_driver_register(drivers[i], owner);
1085 		if (err < 0) {
1086 			pr_err("failed to register platform driver %ps: %d\n",
1087 			       drivers[i], err);
1088 			goto error;
1089 		}
1090 	}
1091 
1092 	return 0;
1093 
1094 error:
1095 	while (i--) {
1096 		pr_debug("unregistering platform driver %ps\n", drivers[i]);
1097 		platform_driver_unregister(drivers[i]);
1098 	}
1099 
1100 	return err;
1101 }
1102 EXPORT_SYMBOL_GPL(__platform_register_drivers);
1103 
1104 /**
1105  * platform_unregister_drivers - unregister an array of platform drivers
1106  * @drivers: an array of drivers to unregister
1107  * @count: the number of drivers to unregister
1108  *
1109  * Unregisters platform drivers specified by an array. This is typically used
1110  * to complement an earlier call to platform_register_drivers(). Drivers are
1111  * unregistered in the reverse order in which they were registered.
1112  */
platform_unregister_drivers(struct platform_driver * const * drivers,unsigned int count)1113 void platform_unregister_drivers(struct platform_driver * const *drivers,
1114 				 unsigned int count)
1115 {
1116 	while (count--) {
1117 		pr_debug("unregistering platform driver %ps\n", drivers[count]);
1118 		platform_driver_unregister(drivers[count]);
1119 	}
1120 }
1121 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1122 
1123 static const struct platform_device_id *
platform_match_id(const struct platform_device_id * id,struct platform_device * pdev)1124 platform_match_id(const struct platform_device_id *id, struct platform_device *pdev)
1125 {
1126 	while (id->name[0]) {
1127 		if (strcmp(pdev->name, id->name) == 0) {
1128 			pdev->id_entry = id;
1129 			return id;
1130 		}
1131 		id++;
1132 	}
1133 	return NULL;
1134 }
1135 
1136 #ifdef CONFIG_PM_SLEEP
1137 
platform_legacy_suspend(struct device * dev,pm_message_t mesg)1138 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1139 {
1140 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1141 	struct platform_device *pdev = to_platform_device(dev);
1142 	int ret = 0;
1143 
1144 	if (dev->driver && pdrv->suspend)
1145 		ret = pdrv->suspend(pdev, mesg);
1146 
1147 	return ret;
1148 }
1149 
platform_legacy_resume(struct device * dev)1150 static int platform_legacy_resume(struct device *dev)
1151 {
1152 	struct platform_driver *pdrv = to_platform_driver(dev->driver);
1153 	struct platform_device *pdev = to_platform_device(dev);
1154 	int ret = 0;
1155 
1156 	if (dev->driver && pdrv->resume)
1157 		ret = pdrv->resume(pdev);
1158 
1159 	return ret;
1160 }
1161 
1162 #endif /* CONFIG_PM_SLEEP */
1163 
1164 #ifdef CONFIG_SUSPEND
1165 
platform_pm_suspend(struct device * dev)1166 int platform_pm_suspend(struct device *dev)
1167 {
1168 	const struct device_driver *drv = dev->driver;
1169 	int ret = 0;
1170 
1171 	if (!drv)
1172 		return 0;
1173 
1174 	if (drv->pm) {
1175 		if (drv->pm->suspend)
1176 			ret = drv->pm->suspend(dev);
1177 	} else {
1178 		ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1179 	}
1180 
1181 	return ret;
1182 }
1183 
platform_pm_resume(struct device * dev)1184 int platform_pm_resume(struct device *dev)
1185 {
1186 	const struct device_driver *drv = dev->driver;
1187 	int ret = 0;
1188 
1189 	if (!drv)
1190 		return 0;
1191 
1192 	if (drv->pm) {
1193 		if (drv->pm->resume)
1194 			ret = drv->pm->resume(dev);
1195 	} else {
1196 		ret = platform_legacy_resume(dev);
1197 	}
1198 
1199 	return ret;
1200 }
1201 
1202 #endif /* CONFIG_SUSPEND */
1203 
1204 #ifdef CONFIG_HIBERNATE_CALLBACKS
1205 
platform_pm_freeze(struct device * dev)1206 int platform_pm_freeze(struct device *dev)
1207 {
1208 	const struct device_driver *drv = dev->driver;
1209 	int ret = 0;
1210 
1211 	if (!drv)
1212 		return 0;
1213 
1214 	if (drv->pm) {
1215 		if (drv->pm->freeze)
1216 			ret = drv->pm->freeze(dev);
1217 	} else {
1218 		ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1219 	}
1220 
1221 	return ret;
1222 }
1223 
platform_pm_thaw(struct device * dev)1224 int platform_pm_thaw(struct device *dev)
1225 {
1226 	const struct device_driver *drv = dev->driver;
1227 	int ret = 0;
1228 
1229 	if (!drv)
1230 		return 0;
1231 
1232 	if (drv->pm) {
1233 		if (drv->pm->thaw)
1234 			ret = drv->pm->thaw(dev);
1235 	} else {
1236 		ret = platform_legacy_resume(dev);
1237 	}
1238 
1239 	return ret;
1240 }
1241 
platform_pm_poweroff(struct device * dev)1242 int platform_pm_poweroff(struct device *dev)
1243 {
1244 	const struct device_driver *drv = dev->driver;
1245 	int ret = 0;
1246 
1247 	if (!drv)
1248 		return 0;
1249 
1250 	if (drv->pm) {
1251 		if (drv->pm->poweroff)
1252 			ret = drv->pm->poweroff(dev);
1253 	} else {
1254 		ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1255 	}
1256 
1257 	return ret;
1258 }
1259 
platform_pm_restore(struct device * dev)1260 int platform_pm_restore(struct device *dev)
1261 {
1262 	const struct device_driver *drv = dev->driver;
1263 	int ret = 0;
1264 
1265 	if (!drv)
1266 		return 0;
1267 
1268 	if (drv->pm) {
1269 		if (drv->pm->restore)
1270 			ret = drv->pm->restore(dev);
1271 	} else {
1272 		ret = platform_legacy_resume(dev);
1273 	}
1274 
1275 	return ret;
1276 }
1277 
1278 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1279 
1280 /* modalias support enables more hands-off userspace setup:
1281  * (a) environment variable lets new-style hotplug events work once system is
1282  *     fully running:  "modprobe $MODALIAS"
1283  * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1284  *     mishandled before system is fully running:  "modprobe $(cat modalias)"
1285  */
modalias_show(struct device * dev,struct device_attribute * attr,char * buf)1286 static ssize_t modalias_show(struct device *dev,
1287 			     struct device_attribute *attr, char *buf)
1288 {
1289 	struct platform_device *pdev = to_platform_device(dev);
1290 	int len;
1291 
1292 	len = of_device_modalias(dev, buf, PAGE_SIZE);
1293 	if (len != -ENODEV)
1294 		return len;
1295 
1296 	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1297 	if (len != -ENODEV)
1298 		return len;
1299 
1300 	return sysfs_emit(buf, "platform:%s\n", pdev->name);
1301 }
1302 static DEVICE_ATTR_RO(modalias);
1303 
numa_node_show(struct device * dev,struct device_attribute * attr,char * buf)1304 static ssize_t numa_node_show(struct device *dev,
1305 			      struct device_attribute *attr, char *buf)
1306 {
1307 	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1308 }
1309 static DEVICE_ATTR_RO(numa_node);
1310 
1311 static struct attribute *platform_dev_attrs[] = {
1312 	&dev_attr_modalias.attr,
1313 	&dev_attr_numa_node.attr,
1314 	NULL,
1315 };
1316 
platform_dev_attrs_visible(struct kobject * kobj,struct attribute * a,int n)1317 static umode_t platform_dev_attrs_visible(struct kobject *kobj,
1318 					  struct attribute *a, int n)
1319 {
1320 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
1321 
1322 	if (a == &dev_attr_numa_node.attr && dev_to_node(dev) == NUMA_NO_NODE)
1323 		return 0;
1324 
1325 	return a->mode;
1326 }
1327 
1328 static const struct attribute_group platform_dev_group = {
1329 	.attrs = platform_dev_attrs,
1330 	.is_visible = platform_dev_attrs_visible,
1331 };
1332 __ATTRIBUTE_GROUPS(platform_dev);
1333 
1334 /**
1335  * platform_match - bind platform device to platform driver.
1336  * @dev: device.
1337  * @drv: driver.
1338  *
1339  * Platform device IDs are assumed to be encoded like this:
1340  * "<name><instance>", where <name> is a short description of the type of
1341  * device, like "pci" or "floppy", and <instance> is the enumerated
1342  * instance of the device, like '0' or '42'.  Driver IDs are simply
1343  * "<name>".  So, extract the <name> from the platform_device structure,
1344  * and compare it against the name of the driver. Return whether they match
1345  * or not.
1346  */
platform_match(struct device * dev,const struct device_driver * drv)1347 static int platform_match(struct device *dev, const struct device_driver *drv)
1348 {
1349 	struct platform_device *pdev = to_platform_device(dev);
1350 	struct platform_driver *pdrv = to_platform_driver(drv);
1351 	int ret;
1352 
1353 	/* When driver_override is set, only bind to the matching driver */
1354 	ret = device_match_driver_override(dev, drv);
1355 	if (ret >= 0)
1356 		return ret;
1357 
1358 	/* Attempt an OF style match first */
1359 	if (of_driver_match_device(dev, drv))
1360 		return 1;
1361 
1362 	/* Then try ACPI style match */
1363 	if (acpi_driver_match_device(dev, drv))
1364 		return 1;
1365 
1366 	/* Then try to match against the id table */
1367 	if (pdrv->id_table)
1368 		return platform_match_id(pdrv->id_table, pdev) != NULL;
1369 
1370 	/* fall-back to driver name match */
1371 	return (strcmp(pdev->name, drv->name) == 0);
1372 }
1373 
platform_uevent(const struct device * dev,struct kobj_uevent_env * env)1374 static int platform_uevent(const struct device *dev, struct kobj_uevent_env *env)
1375 {
1376 	const struct platform_device *pdev = to_platform_device(dev);
1377 	int rc;
1378 
1379 	/* Some devices have extra OF data and an OF-style MODALIAS */
1380 	rc = of_device_uevent_modalias(dev, env);
1381 	if (rc != -ENODEV)
1382 		return rc;
1383 
1384 	rc = acpi_device_uevent_modalias(dev, env);
1385 	if (rc != -ENODEV)
1386 		return rc;
1387 
1388 	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX, pdev->name);
1389 	return 0;
1390 }
1391 
platform_probe(struct device * _dev)1392 static int platform_probe(struct device *_dev)
1393 {
1394 	struct platform_driver *drv = to_platform_driver(_dev->driver);
1395 	struct platform_device *dev = to_platform_device(_dev);
1396 	int ret;
1397 
1398 	/*
1399 	 * A driver registered using platform_driver_probe() cannot be bound
1400 	 * again later because the probe function usually lives in __init code
1401 	 * and so is gone. For these drivers .probe is set to
1402 	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1403 	 * clocks and PM domains for these to match the traditional behaviour.
1404 	 */
1405 	if (unlikely(drv->probe == platform_probe_fail))
1406 		return -ENXIO;
1407 
1408 	ret = of_clk_set_defaults(_dev->of_node, false);
1409 	if (ret < 0)
1410 		return ret;
1411 
1412 	ret = dev_pm_domain_attach(_dev, PD_FLAG_ATTACH_POWER_ON |
1413 					 PD_FLAG_DETACH_POWER_OFF);
1414 	if (ret)
1415 		goto out;
1416 
1417 	if (drv->probe)
1418 		ret = drv->probe(dev);
1419 
1420 out:
1421 	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1422 		dev_warn(_dev, "probe deferral not supported\n");
1423 		ret = -ENXIO;
1424 	}
1425 
1426 	return ret;
1427 }
1428 
platform_remove(struct device * _dev)1429 static void platform_remove(struct device *_dev)
1430 {
1431 	struct platform_driver *drv = to_platform_driver(_dev->driver);
1432 	struct platform_device *dev = to_platform_device(_dev);
1433 
1434 	if (drv->remove)
1435 		drv->remove(dev);
1436 }
1437 
platform_shutdown(struct device * _dev)1438 static void platform_shutdown(struct device *_dev)
1439 {
1440 	struct platform_device *dev = to_platform_device(_dev);
1441 	struct platform_driver *drv;
1442 
1443 	if (!_dev->driver)
1444 		return;
1445 
1446 	drv = to_platform_driver(_dev->driver);
1447 	if (drv->shutdown)
1448 		drv->shutdown(dev);
1449 }
1450 
platform_dma_configure(struct device * dev)1451 static int platform_dma_configure(struct device *dev)
1452 {
1453 	struct device_driver *drv = READ_ONCE(dev->driver);
1454 	struct fwnode_handle *fwnode = dev_fwnode(dev);
1455 	enum dev_dma_attr attr;
1456 	int ret = 0;
1457 
1458 	if (is_of_node(fwnode)) {
1459 		ret = of_dma_configure(dev, to_of_node(fwnode), true);
1460 	} else if (is_acpi_device_node(fwnode)) {
1461 		attr = acpi_get_dma_attr(to_acpi_device_node(fwnode));
1462 		ret = acpi_dma_configure(dev, attr);
1463 	}
1464 	/* @dev->driver may not be valid when we're called from the IOMMU layer */
1465 	if (ret || !drv || to_platform_driver(drv)->driver_managed_dma)
1466 		return ret;
1467 
1468 	ret = iommu_device_use_default_domain(dev);
1469 	if (ret)
1470 		arch_teardown_dma_ops(dev);
1471 
1472 	return ret;
1473 }
1474 
platform_dma_cleanup(struct device * dev)1475 static void platform_dma_cleanup(struct device *dev)
1476 {
1477 	struct platform_driver *drv = to_platform_driver(dev->driver);
1478 
1479 	if (!drv->driver_managed_dma)
1480 		iommu_device_unuse_default_domain(dev);
1481 }
1482 
1483 static const struct dev_pm_ops platform_dev_pm_ops = {
1484 	SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
1485 	USE_PLATFORM_PM_SLEEP_OPS
1486 };
1487 
1488 const struct bus_type platform_bus_type = {
1489 	.name		= "platform",
1490 	.dev_groups	= platform_dev_groups,
1491 	.driver_override = true,
1492 	.match		= platform_match,
1493 	.uevent		= platform_uevent,
1494 	.probe		= platform_probe,
1495 	.remove		= platform_remove,
1496 	.shutdown	= platform_shutdown,
1497 	.dma_configure	= platform_dma_configure,
1498 	.dma_cleanup	= platform_dma_cleanup,
1499 	.pm		= &platform_dev_pm_ops,
1500 };
1501 EXPORT_SYMBOL_GPL(platform_bus_type);
1502 
__platform_match(struct device * dev,const void * drv)1503 static inline int __platform_match(struct device *dev, const void *drv)
1504 {
1505 	return platform_match(dev, (struct device_driver *)drv);
1506 }
1507 
1508 /**
1509  * platform_find_device_by_driver - Find a platform device with a given
1510  * driver.
1511  * @start: The device to start the search from.
1512  * @drv: The device driver to look for.
1513  */
platform_find_device_by_driver(struct device * start,const struct device_driver * drv)1514 struct device *platform_find_device_by_driver(struct device *start,
1515 					      const struct device_driver *drv)
1516 {
1517 	return bus_find_device(&platform_bus_type, start, drv,
1518 			       __platform_match);
1519 }
1520 EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1521 
early_platform_cleanup(void)1522 void __weak __init early_platform_cleanup(void) { }
1523 
platform_bus_init(void)1524 int __init platform_bus_init(void)
1525 {
1526 	int error;
1527 
1528 	early_platform_cleanup();
1529 
1530 	error = device_register(&platform_bus);
1531 	if (error) {
1532 		put_device(&platform_bus);
1533 		return error;
1534 	}
1535 	error =  bus_register(&platform_bus_type);
1536 	if (error)
1537 		device_unregister(&platform_bus);
1538 
1539 	return error;
1540 }
1541