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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#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 */
40static DEFINE_IDA(platform_devid_ida);
41
42struct device platform_bus = {
43 .init_name = "platform",
44};
45EXPORT_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 */
55struct 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}
68EXPORT_SYMBOL_GPL(platform_get_resource);
69
70struct 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}
83EXPORT_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 */
98void __iomem *
99devm_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}
109EXPORT_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 */
122void __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}
127EXPORT_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 */
141void __iomem *
142devm_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}
150EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname);
151#endif /* CONFIG_HAS_IOMEM */
152
153/**
154 * platform_get_irq_optional - get an optional IRQ for a device
155 * @dev: platform device
156 * @num: IRQ number index
157 *
158 * Gets an IRQ for a platform device. Device drivers should check the return
159 * value for errors so as to not pass a negative integer value to the
160 * request_irq() APIs. This is the same as platform_get_irq(), except that it
161 * does not print an error message if an IRQ can not be obtained.
162 *
163 * For example::
164 *
165 * int irq = platform_get_irq_optional(pdev, 0);
166 * if (irq < 0)
167 * return irq;
168 *
169 * Return: non-zero IRQ number on success, negative error number on failure.
170 */
171int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
172{
173 int ret;
174#ifdef CONFIG_SPARC
175 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
176 if (!dev || num >= dev->archdata.num_irqs)
177 goto out_not_found;
178 ret = dev->archdata.irqs[num];
179 goto out;
180#else
181 struct resource *r;
182
183 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
184 ret = of_irq_get(dev->dev.of_node, num);
185 if (ret > 0 || ret == -EPROBE_DEFER)
186 goto out;
187 }
188
189 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
190 if (has_acpi_companion(&dev->dev)) {
191 if (r && r->flags & IORESOURCE_DISABLED) {
192 ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
193 if (ret)
194 goto out;
195 }
196 }
197
198 /*
199 * The resources may pass trigger flags to the irqs that need
200 * to be set up. It so happens that the trigger flags for
201 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
202 * settings.
203 */
204 if (r && r->flags & IORESOURCE_BITS) {
205 struct irq_data *irqd;
206
207 irqd = irq_get_irq_data(r->start);
208 if (!irqd)
209 goto out_not_found;
210 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
211 }
212
213 if (r) {
214 ret = r->start;
215 goto out;
216 }
217
218 /*
219 * For the index 0 interrupt, allow falling back to GpioInt
220 * resources. While a device could have both Interrupt and GpioInt
221 * resources, making this fallback ambiguous, in many common cases
222 * the device will only expose one IRQ, and this fallback
223 * allows a common code path across either kind of resource.
224 */
225 if (num == 0 && has_acpi_companion(&dev->dev)) {
226 ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
227 /* Our callers expect -ENXIO for missing IRQs. */
228 if (ret >= 0 || ret == -EPROBE_DEFER)
229 goto out;
230 }
231
232#endif
233out_not_found:
234 ret = -ENXIO;
235out:
236 if (WARN(!ret, "0 is an invalid IRQ number\n"))
237 return -EINVAL;
238 return ret;
239}
240EXPORT_SYMBOL_GPL(platform_get_irq_optional);
241
242/**
243 * platform_get_irq - get an IRQ for a device
244 * @dev: platform device
245 * @num: IRQ number index
246 *
247 * Gets an IRQ for a platform device and prints an error message if finding the
248 * IRQ fails. Device drivers should check the return value for errors so as to
249 * not pass a negative integer value to the request_irq() APIs.
250 *
251 * For example::
252 *
253 * int irq = platform_get_irq(pdev, 0);
254 * if (irq < 0)
255 * return irq;
256 *
257 * Return: non-zero IRQ number on success, negative error number on failure.
258 */
259int platform_get_irq(struct platform_device *dev, unsigned int num)
260{
261 int ret;
262
263 ret = platform_get_irq_optional(dev, num);
264 if (ret < 0)
265 return dev_err_probe(&dev->dev, ret,
266 "IRQ index %u not found\n", num);
267
268 return ret;
269}
270EXPORT_SYMBOL_GPL(platform_get_irq);
271
272/**
273 * platform_irq_count - Count the number of IRQs a platform device uses
274 * @dev: platform device
275 *
276 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
277 */
278int platform_irq_count(struct platform_device *dev)
279{
280 int ret, nr = 0;
281
282 while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
283 nr++;
284
285 if (ret == -EPROBE_DEFER)
286 return ret;
287
288 return nr;
289}
290EXPORT_SYMBOL_GPL(platform_irq_count);
291
292struct irq_affinity_devres {
293 unsigned int count;
294 unsigned int irq[];
295};
296
297static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
298{
299 struct resource *r;
300
301 r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
302 if (r)
303 irqresource_disabled(r, 0);
304}
305
306static void devm_platform_get_irqs_affinity_release(struct device *dev,
307 void *res)
308{
309 struct irq_affinity_devres *ptr = res;
310 int i;
311
312 for (i = 0; i < ptr->count; i++) {
313 irq_dispose_mapping(ptr->irq[i]);
314
315 if (has_acpi_companion(dev))
316 platform_disable_acpi_irq(to_platform_device(dev), i);
317 }
318}
319
320/**
321 * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
322 * device using an interrupt affinity descriptor
323 * @dev: platform device pointer
324 * @affd: affinity descriptor
325 * @minvec: minimum count of interrupt vectors
326 * @maxvec: maximum count of interrupt vectors
327 * @irqs: pointer holder for IRQ numbers
328 *
329 * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
330 * to the passed affinity descriptor
331 *
332 * Return: Number of vectors on success, negative error number on failure.
333 */
334int devm_platform_get_irqs_affinity(struct platform_device *dev,
335 struct irq_affinity *affd,
336 unsigned int minvec,
337 unsigned int maxvec,
338 int **irqs)
339{
340 struct irq_affinity_devres *ptr;
341 struct irq_affinity_desc *desc;
342 size_t size;
343 int i, ret, nvec;
344
345 if (!affd)
346 return -EPERM;
347
348 if (maxvec < minvec)
349 return -ERANGE;
350
351 nvec = platform_irq_count(dev);
352 if (nvec < 0)
353 return nvec;
354
355 if (nvec < minvec)
356 return -ENOSPC;
357
358 nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
359 if (nvec < minvec)
360 return -ENOSPC;
361
362 if (nvec > maxvec)
363 nvec = maxvec;
364
365 size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
366 ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
367 GFP_KERNEL);
368 if (!ptr)
369 return -ENOMEM;
370
371 ptr->count = nvec;
372
373 for (i = 0; i < nvec; i++) {
374 int irq = platform_get_irq(dev, i);
375 if (irq < 0) {
376 ret = irq;
377 goto err_free_devres;
378 }
379 ptr->irq[i] = irq;
380 }
381
382 desc = irq_create_affinity_masks(nvec, affd);
383 if (!desc) {
384 ret = -ENOMEM;
385 goto err_free_devres;
386 }
387
388 for (i = 0; i < nvec; i++) {
389 ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
390 if (ret) {
391 dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
392 ptr->irq[i], ret);
393 goto err_free_desc;
394 }
395 }
396
397 devres_add(&dev->dev, ptr);
398
399 kfree(desc);
400
401 *irqs = ptr->irq;
402
403 return nvec;
404
405err_free_desc:
406 kfree(desc);
407err_free_devres:
408 devres_free(ptr);
409 return ret;
410}
411EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
412
413/**
414 * platform_get_resource_byname - get a resource for a device by name
415 * @dev: platform device
416 * @type: resource type
417 * @name: resource name
418 */
419struct resource *platform_get_resource_byname(struct platform_device *dev,
420 unsigned int type,
421 const char *name)
422{
423 u32 i;
424
425 for (i = 0; i < dev->num_resources; i++) {
426 struct resource *r = &dev->resource[i];
427
428 if (unlikely(!r->name))
429 continue;
430
431 if (type == resource_type(r) && !strcmp(r->name, name))
432 return r;
433 }
434 return NULL;
435}
436EXPORT_SYMBOL_GPL(platform_get_resource_byname);
437
438static int __platform_get_irq_byname(struct platform_device *dev,
439 const char *name)
440{
441 struct resource *r;
442 int ret;
443
444 if (!dev->dev.of_node || IS_ENABLED(CONFIG_OF_IRQ)) {
445 ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
446 if (ret > 0 || ret == -EPROBE_DEFER)
447 return ret;
448 }
449
450 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
451 if (r) {
452 if (WARN(!r->start, "0 is an invalid IRQ number\n"))
453 return -EINVAL;
454 return r->start;
455 }
456
457 return -ENXIO;
458}
459
460/**
461 * platform_get_irq_byname - get an IRQ for a device by name
462 * @dev: platform device
463 * @name: IRQ name
464 *
465 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
466 *
467 * Return: non-zero IRQ number on success, negative error number on failure.
468 */
469int platform_get_irq_byname(struct platform_device *dev, const char *name)
470{
471 int ret;
472
473 ret = __platform_get_irq_byname(dev, name);
474 if (ret < 0)
475 return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
476 name);
477 return ret;
478}
479EXPORT_SYMBOL_GPL(platform_get_irq_byname);
480
481/**
482 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
483 * @dev: platform device
484 * @name: IRQ name
485 *
486 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
487 * does not print an error message if an IRQ can not be obtained.
488 *
489 * Return: non-zero IRQ number on success, negative error number on failure.
490 */
491int platform_get_irq_byname_optional(struct platform_device *dev,
492 const char *name)
493{
494 return __platform_get_irq_byname(dev, name);
495}
496EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
497
498/**
499 * platform_add_devices - add a numbers of platform devices
500 * @devs: array of platform devices to add
501 * @num: number of platform devices in array
502 */
503int platform_add_devices(struct platform_device **devs, int num)
504{
505 int i, ret = 0;
506
507 for (i = 0; i < num; i++) {
508 ret = platform_device_register(devs[i]);
509 if (ret) {
510 while (--i >= 0)
511 platform_device_unregister(devs[i]);
512 break;
513 }
514 }
515
516 return ret;
517}
518EXPORT_SYMBOL_GPL(platform_add_devices);
519
520struct platform_object {
521 struct platform_device pdev;
522 char name[];
523};
524
525/*
526 * Set up default DMA mask for platform devices if the they weren't
527 * previously set by the architecture / DT.
528 */
529static void setup_pdev_dma_masks(struct platform_device *pdev)
530{
531 pdev->dev.dma_parms = &pdev->dma_parms;
532
533 if (!pdev->dev.coherent_dma_mask)
534 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
535 if (!pdev->dev.dma_mask) {
536 pdev->platform_dma_mask = DMA_BIT_MASK(32);
537 pdev->dev.dma_mask = &pdev->platform_dma_mask;
538 }
539};
540
541/**
542 * platform_device_put - destroy a platform device
543 * @pdev: platform device to free
544 *
545 * Free all memory associated with a platform device. This function must
546 * _only_ be externally called in error cases. All other usage is a bug.
547 */
548void platform_device_put(struct platform_device *pdev)
549{
550 if (!IS_ERR_OR_NULL(pdev))
551 put_device(&pdev->dev);
552}
553EXPORT_SYMBOL_GPL(platform_device_put);
554
555static void platform_device_release(struct device *dev)
556{
557 struct platform_object *pa = container_of(dev, struct platform_object,
558 pdev.dev);
559
560 of_node_put(pa->pdev.dev.of_node);
561 kfree(pa->pdev.dev.platform_data);
562 kfree(pa->pdev.mfd_cell);
563 kfree(pa->pdev.resource);
564 kfree(pa->pdev.driver_override);
565 kfree(pa);
566}
567
568/**
569 * platform_device_alloc - create a platform device
570 * @name: base name of the device we're adding
571 * @id: instance id
572 *
573 * Create a platform device object which can have other objects attached
574 * to it, and which will have attached objects freed when it is released.
575 */
576struct platform_device *platform_device_alloc(const char *name, int id)
577{
578 struct platform_object *pa;
579
580 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
581 if (pa) {
582 strcpy(pa->name, name);
583 pa->pdev.name = pa->name;
584 pa->pdev.id = id;
585 device_initialize(&pa->pdev.dev);
586 pa->pdev.dev.release = platform_device_release;
587 setup_pdev_dma_masks(&pa->pdev);
588 }
589
590 return pa ? &pa->pdev : NULL;
591}
592EXPORT_SYMBOL_GPL(platform_device_alloc);
593
594/**
595 * platform_device_add_resources - add resources to a platform device
596 * @pdev: platform device allocated by platform_device_alloc to add resources to
597 * @res: set of resources that needs to be allocated for the device
598 * @num: number of resources
599 *
600 * Add a copy of the resources to the platform device. The memory
601 * associated with the resources will be freed when the platform device is
602 * released.
603 */
604int platform_device_add_resources(struct platform_device *pdev,
605 const struct resource *res, unsigned int num)
606{
607 struct resource *r = NULL;
608
609 if (res) {
610 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
611 if (!r)
612 return -ENOMEM;
613 }
614
615 kfree(pdev->resource);
616 pdev->resource = r;
617 pdev->num_resources = num;
618 return 0;
619}
620EXPORT_SYMBOL_GPL(platform_device_add_resources);
621
622/**
623 * platform_device_add_data - add platform-specific data to a platform device
624 * @pdev: platform device allocated by platform_device_alloc to add resources to
625 * @data: platform specific data for this platform device
626 * @size: size of platform specific data
627 *
628 * Add a copy of platform specific data to the platform device's
629 * platform_data pointer. The memory associated with the platform data
630 * will be freed when the platform device is released.
631 */
632int platform_device_add_data(struct platform_device *pdev, const void *data,
633 size_t size)
634{
635 void *d = NULL;
636
637 if (data) {
638 d = kmemdup(data, size, GFP_KERNEL);
639 if (!d)
640 return -ENOMEM;
641 }
642
643 kfree(pdev->dev.platform_data);
644 pdev->dev.platform_data = d;
645 return 0;
646}
647EXPORT_SYMBOL_GPL(platform_device_add_data);
648
649/**
650 * platform_device_add - add a platform device to device hierarchy
651 * @pdev: platform device we're adding
652 *
653 * This is part 2 of platform_device_register(), though may be called
654 * separately _iff_ pdev was allocated by platform_device_alloc().
655 */
656int platform_device_add(struct platform_device *pdev)
657{
658 u32 i;
659 int ret;
660
661 if (!pdev)
662 return -EINVAL;
663
664 if (!pdev->dev.parent)
665 pdev->dev.parent = &platform_bus;
666
667 pdev->dev.bus = &platform_bus_type;
668
669 switch (pdev->id) {
670 default:
671 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
672 break;
673 case PLATFORM_DEVID_NONE:
674 dev_set_name(&pdev->dev, "%s", pdev->name);
675 break;
676 case PLATFORM_DEVID_AUTO:
677 /*
678 * Automatically allocated device ID. We mark it as such so
679 * that we remember it must be freed, and we append a suffix
680 * to avoid namespace collision with explicit IDs.
681 */
682 ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
683 if (ret < 0)
684 goto err_out;
685 pdev->id = ret;
686 pdev->id_auto = true;
687 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
688 break;
689 }
690
691 for (i = 0; i < pdev->num_resources; i++) {
692 struct resource *p, *r = &pdev->resource[i];
693
694 if (r->name == NULL)
695 r->name = dev_name(&pdev->dev);
696
697 p = r->parent;
698 if (!p) {
699 if (resource_type(r) == IORESOURCE_MEM)
700 p = &iomem_resource;
701 else if (resource_type(r) == IORESOURCE_IO)
702 p = &ioport_resource;
703 }
704
705 if (p) {
706 ret = insert_resource(p, r);
707 if (ret) {
708 dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
709 goto failed;
710 }
711 }
712 }
713
714 pr_debug("Registering platform device '%s'. Parent at %s\n",
715 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
716
717 ret = device_add(&pdev->dev);
718 if (ret == 0)
719 return ret;
720
721 failed:
722 if (pdev->id_auto) {
723 ida_free(&platform_devid_ida, pdev->id);
724 pdev->id = PLATFORM_DEVID_AUTO;
725 }
726
727 while (i--) {
728 struct resource *r = &pdev->resource[i];
729 if (r->parent)
730 release_resource(r);
731 }
732
733 err_out:
734 return ret;
735}
736EXPORT_SYMBOL_GPL(platform_device_add);
737
738/**
739 * platform_device_del - remove a platform-level device
740 * @pdev: platform device we're removing
741 *
742 * Note that this function will also release all memory- and port-based
743 * resources owned by the device (@dev->resource). This function must
744 * _only_ be externally called in error cases. All other usage is a bug.
745 */
746void platform_device_del(struct platform_device *pdev)
747{
748 u32 i;
749
750 if (!IS_ERR_OR_NULL(pdev)) {
751 device_del(&pdev->dev);
752
753 if (pdev->id_auto) {
754 ida_free(&platform_devid_ida, pdev->id);
755 pdev->id = PLATFORM_DEVID_AUTO;
756 }
757
758 for (i = 0; i < pdev->num_resources; i++) {
759 struct resource *r = &pdev->resource[i];
760 if (r->parent)
761 release_resource(r);
762 }
763 }
764}
765EXPORT_SYMBOL_GPL(platform_device_del);
766
767/**
768 * platform_device_register - add a platform-level device
769 * @pdev: platform device we're adding
770 *
771 * NOTE: _Never_ directly free @pdev after calling this function, even if it
772 * returned an error! Always use platform_device_put() to give up the
773 * reference initialised in this function instead.
774 */
775int platform_device_register(struct platform_device *pdev)
776{
777 device_initialize(&pdev->dev);
778 setup_pdev_dma_masks(pdev);
779 return platform_device_add(pdev);
780}
781EXPORT_SYMBOL_GPL(platform_device_register);
782
783/**
784 * platform_device_unregister - unregister a platform-level device
785 * @pdev: platform device we're unregistering
786 *
787 * Unregistration is done in 2 steps. First we release all resources
788 * and remove it from the subsystem, then we drop reference count by
789 * calling platform_device_put().
790 */
791void platform_device_unregister(struct platform_device *pdev)
792{
793 platform_device_del(pdev);
794 platform_device_put(pdev);
795}
796EXPORT_SYMBOL_GPL(platform_device_unregister);
797
798/**
799 * platform_device_register_full - add a platform-level device with
800 * resources and platform-specific data
801 *
802 * @pdevinfo: data used to create device
803 *
804 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
805 */
806struct platform_device *platform_device_register_full(
807 const struct platform_device_info *pdevinfo)
808{
809 int ret;
810 struct platform_device *pdev;
811
812 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
813 if (!pdev)
814 return ERR_PTR(-ENOMEM);
815
816 pdev->dev.parent = pdevinfo->parent;
817 pdev->dev.fwnode = pdevinfo->fwnode;
818 pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
819 pdev->dev.of_node_reused = pdevinfo->of_node_reused;
820
821 if (pdevinfo->dma_mask) {
822 pdev->platform_dma_mask = pdevinfo->dma_mask;
823 pdev->dev.dma_mask = &pdev->platform_dma_mask;
824 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
825 }
826
827 ret = platform_device_add_resources(pdev,
828 pdevinfo->res, pdevinfo->num_res);
829 if (ret)
830 goto err;
831
832 ret = platform_device_add_data(pdev,
833 pdevinfo->data, pdevinfo->size_data);
834 if (ret)
835 goto err;
836
837 if (pdevinfo->properties) {
838 ret = device_create_managed_software_node(&pdev->dev,
839 pdevinfo->properties, NULL);
840 if (ret)
841 goto err;
842 }
843
844 ret = platform_device_add(pdev);
845 if (ret) {
846err:
847 ACPI_COMPANION_SET(&pdev->dev, NULL);
848 platform_device_put(pdev);
849 return ERR_PTR(ret);
850 }
851
852 return pdev;
853}
854EXPORT_SYMBOL_GPL(platform_device_register_full);
855
856/**
857 * __platform_driver_register - register a driver for platform-level devices
858 * @drv: platform driver structure
859 * @owner: owning module/driver
860 */
861int __platform_driver_register(struct platform_driver *drv,
862 struct module *owner)
863{
864 drv->driver.owner = owner;
865 drv->driver.bus = &platform_bus_type;
866
867 return driver_register(&drv->driver);
868}
869EXPORT_SYMBOL_GPL(__platform_driver_register);
870
871/**
872 * platform_driver_unregister - unregister a driver for platform-level devices
873 * @drv: platform driver structure
874 */
875void platform_driver_unregister(struct platform_driver *drv)
876{
877 driver_unregister(&drv->driver);
878}
879EXPORT_SYMBOL_GPL(platform_driver_unregister);
880
881static int platform_probe_fail(struct platform_device *pdev)
882{
883 return -ENXIO;
884}
885
886/**
887 * __platform_driver_probe - register driver for non-hotpluggable device
888 * @drv: platform driver structure
889 * @probe: the driver probe routine, probably from an __init section
890 * @module: module which will be the owner of the driver
891 *
892 * Use this instead of platform_driver_register() when you know the device
893 * is not hotpluggable and has already been registered, and you want to
894 * remove its run-once probe() infrastructure from memory after the driver
895 * has bound to the device.
896 *
897 * One typical use for this would be with drivers for controllers integrated
898 * into system-on-chip processors, where the controller devices have been
899 * configured as part of board setup.
900 *
901 * Note that this is incompatible with deferred probing.
902 *
903 * Returns zero if the driver registered and bound to a device, else returns
904 * a negative error code and with the driver not registered.
905 */
906int __init_or_module __platform_driver_probe(struct platform_driver *drv,
907 int (*probe)(struct platform_device *), struct module *module)
908{
909 int retval, code;
910
911 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
912 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
913 drv->driver.name, __func__);
914 return -EINVAL;
915 }
916
917 /*
918 * We have to run our probes synchronously because we check if
919 * we find any devices to bind to and exit with error if there
920 * are any.
921 */
922 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
923
924 /*
925 * Prevent driver from requesting probe deferral to avoid further
926 * futile probe attempts.
927 */
928 drv->prevent_deferred_probe = true;
929
930 /* make sure driver won't have bind/unbind attributes */
931 drv->driver.suppress_bind_attrs = true;
932
933 /* temporary section violation during probe() */
934 drv->probe = probe;
935 retval = code = __platform_driver_register(drv, module);
936 if (retval)
937 return retval;
938
939 /*
940 * Fixup that section violation, being paranoid about code scanning
941 * the list of drivers in order to probe new devices. Check to see
942 * if the probe was successful, and make sure any forced probes of
943 * new devices fail.
944 */
945 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
946 drv->probe = platform_probe_fail;
947 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
948 retval = -ENODEV;
949 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
950
951 if (code != retval)
952 platform_driver_unregister(drv);
953 return retval;
954}
955EXPORT_SYMBOL_GPL(__platform_driver_probe);
956
957/**
958 * __platform_create_bundle - register driver and create corresponding device
959 * @driver: platform driver structure
960 * @probe: the driver probe routine, probably from an __init section
961 * @res: set of resources that needs to be allocated for the device
962 * @n_res: number of resources
963 * @data: platform specific data for this platform device
964 * @size: size of platform specific data
965 * @module: module which will be the owner of the driver
966 *
967 * Use this in legacy-style modules that probe hardware directly and
968 * register a single platform device and corresponding platform driver.
969 *
970 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
971 */
972struct platform_device * __init_or_module __platform_create_bundle(
973 struct platform_driver *driver,
974 int (*probe)(struct platform_device *),
975 struct resource *res, unsigned int n_res,
976 const void *data, size_t size, struct module *module)
977{
978 struct platform_device *pdev;
979 int error;
980
981 pdev = platform_device_alloc(driver->driver.name, -1);
982 if (!pdev) {
983 error = -ENOMEM;
984 goto err_out;
985 }
986
987 error = platform_device_add_resources(pdev, res, n_res);
988 if (error)
989 goto err_pdev_put;
990
991 error = platform_device_add_data(pdev, data, size);
992 if (error)
993 goto err_pdev_put;
994
995 error = platform_device_add(pdev);
996 if (error)
997 goto err_pdev_put;
998
999 error = __platform_driver_probe(driver, probe, module);
1000 if (error)
1001 goto err_pdev_del;
1002
1003 return pdev;
1004
1005err_pdev_del:
1006 platform_device_del(pdev);
1007err_pdev_put:
1008 platform_device_put(pdev);
1009err_out:
1010 return ERR_PTR(error);
1011}
1012EXPORT_SYMBOL_GPL(__platform_create_bundle);
1013
1014/**
1015 * __platform_register_drivers - register an array of platform drivers
1016 * @drivers: an array of drivers to register
1017 * @count: the number of drivers to register
1018 * @owner: module owning the drivers
1019 *
1020 * Registers platform drivers specified by an array. On failure to register a
1021 * driver, all previously registered drivers will be unregistered. Callers of
1022 * this API should use platform_unregister_drivers() to unregister drivers in
1023 * the reverse order.
1024 *
1025 * Returns: 0 on success or a negative error code on failure.
1026 */
1027int __platform_register_drivers(struct platform_driver * const *drivers,
1028 unsigned int count, struct module *owner)
1029{
1030 unsigned int i;
1031 int err;
1032
1033 for (i = 0; i < count; i++) {
1034 pr_debug("registering platform driver %ps\n", drivers[i]);
1035
1036 err = __platform_driver_register(drivers[i], owner);
1037 if (err < 0) {
1038 pr_err("failed to register platform driver %ps: %d\n",
1039 drivers[i], err);
1040 goto error;
1041 }
1042 }
1043
1044 return 0;
1045
1046error:
1047 while (i--) {
1048 pr_debug("unregistering platform driver %ps\n", drivers[i]);
1049 platform_driver_unregister(drivers[i]);
1050 }
1051
1052 return err;
1053}
1054EXPORT_SYMBOL_GPL(__platform_register_drivers);
1055
1056/**
1057 * platform_unregister_drivers - unregister an array of platform drivers
1058 * @drivers: an array of drivers to unregister
1059 * @count: the number of drivers to unregister
1060 *
1061 * Unregisters platform drivers specified by an array. This is typically used
1062 * to complement an earlier call to platform_register_drivers(). Drivers are
1063 * unregistered in the reverse order in which they were registered.
1064 */
1065void platform_unregister_drivers(struct platform_driver * const *drivers,
1066 unsigned int count)
1067{
1068 while (count--) {
1069 pr_debug("unregistering platform driver %ps\n", drivers[count]);
1070 platform_driver_unregister(drivers[count]);
1071 }
1072}
1073EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1074
1075static const struct platform_device_id *platform_match_id(
1076 const struct platform_device_id *id,
1077 struct platform_device *pdev)
1078{
1079 while (id->name[0]) {
1080 if (strcmp(pdev->name, id->name) == 0) {
1081 pdev->id_entry = id;
1082 return id;
1083 }
1084 id++;
1085 }
1086 return NULL;
1087}
1088
1089#ifdef CONFIG_PM_SLEEP
1090
1091static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1092{
1093 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1094 struct platform_device *pdev = to_platform_device(dev);
1095 int ret = 0;
1096
1097 if (dev->driver && pdrv->suspend)
1098 ret = pdrv->suspend(pdev, mesg);
1099
1100 return ret;
1101}
1102
1103static int platform_legacy_resume(struct device *dev)
1104{
1105 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1106 struct platform_device *pdev = to_platform_device(dev);
1107 int ret = 0;
1108
1109 if (dev->driver && pdrv->resume)
1110 ret = pdrv->resume(pdev);
1111
1112 return ret;
1113}
1114
1115#endif /* CONFIG_PM_SLEEP */
1116
1117#ifdef CONFIG_SUSPEND
1118
1119int platform_pm_suspend(struct device *dev)
1120{
1121 struct device_driver *drv = dev->driver;
1122 int ret = 0;
1123
1124 if (!drv)
1125 return 0;
1126
1127 if (drv->pm) {
1128 if (drv->pm->suspend)
1129 ret = drv->pm->suspend(dev);
1130 } else {
1131 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1132 }
1133
1134 return ret;
1135}
1136
1137int platform_pm_resume(struct device *dev)
1138{
1139 struct device_driver *drv = dev->driver;
1140 int ret = 0;
1141
1142 if (!drv)
1143 return 0;
1144
1145 if (drv->pm) {
1146 if (drv->pm->resume)
1147 ret = drv->pm->resume(dev);
1148 } else {
1149 ret = platform_legacy_resume(dev);
1150 }
1151
1152 return ret;
1153}
1154
1155#endif /* CONFIG_SUSPEND */
1156
1157#ifdef CONFIG_HIBERNATE_CALLBACKS
1158
1159int platform_pm_freeze(struct device *dev)
1160{
1161 struct device_driver *drv = dev->driver;
1162 int ret = 0;
1163
1164 if (!drv)
1165 return 0;
1166
1167 if (drv->pm) {
1168 if (drv->pm->freeze)
1169 ret = drv->pm->freeze(dev);
1170 } else {
1171 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1172 }
1173
1174 return ret;
1175}
1176
1177int platform_pm_thaw(struct device *dev)
1178{
1179 struct device_driver *drv = dev->driver;
1180 int ret = 0;
1181
1182 if (!drv)
1183 return 0;
1184
1185 if (drv->pm) {
1186 if (drv->pm->thaw)
1187 ret = drv->pm->thaw(dev);
1188 } else {
1189 ret = platform_legacy_resume(dev);
1190 }
1191
1192 return ret;
1193}
1194
1195int platform_pm_poweroff(struct device *dev)
1196{
1197 struct device_driver *drv = dev->driver;
1198 int ret = 0;
1199
1200 if (!drv)
1201 return 0;
1202
1203 if (drv->pm) {
1204 if (drv->pm->poweroff)
1205 ret = drv->pm->poweroff(dev);
1206 } else {
1207 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1208 }
1209
1210 return ret;
1211}
1212
1213int platform_pm_restore(struct device *dev)
1214{
1215 struct device_driver *drv = dev->driver;
1216 int ret = 0;
1217
1218 if (!drv)
1219 return 0;
1220
1221 if (drv->pm) {
1222 if (drv->pm->restore)
1223 ret = drv->pm->restore(dev);
1224 } else {
1225 ret = platform_legacy_resume(dev);
1226 }
1227
1228 return ret;
1229}
1230
1231#endif /* CONFIG_HIBERNATE_CALLBACKS */
1232
1233/* modalias support enables more hands-off userspace setup:
1234 * (a) environment variable lets new-style hotplug events work once system is
1235 * fully running: "modprobe $MODALIAS"
1236 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1237 * mishandled before system is fully running: "modprobe $(cat modalias)"
1238 */
1239static ssize_t modalias_show(struct device *dev,
1240 struct device_attribute *attr, char *buf)
1241{
1242 struct platform_device *pdev = to_platform_device(dev);
1243 int len;
1244
1245 len = of_device_modalias(dev, buf, PAGE_SIZE);
1246 if (len != -ENODEV)
1247 return len;
1248
1249 len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1250 if (len != -ENODEV)
1251 return len;
1252
1253 return sysfs_emit(buf, "platform:%s\n", pdev->name);
1254}
1255static DEVICE_ATTR_RO(modalias);
1256
1257static ssize_t numa_node_show(struct device *dev,
1258 struct device_attribute *attr, char *buf)
1259{
1260 return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1261}
1262static DEVICE_ATTR_RO(numa_node);
1263
1264static ssize_t driver_override_show(struct device *dev,
1265 struct device_attribute *attr, char *buf)
1266{
1267 struct platform_device *pdev = to_platform_device(dev);
1268 ssize_t len;
1269
1270 device_lock(dev);
1271 len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1272 device_unlock(dev);
1273
1274 return len;
1275}
1276
1277static ssize_t driver_override_store(struct device *dev,
1278 struct device_attribute *attr,
1279 const char *buf, size_t count)
1280{
1281 struct platform_device *pdev = to_platform_device(dev);
1282 int ret;
1283
1284 ret = driver_set_override(dev, &pdev->driver_override, buf, count);
1285 if (ret)
1286 return ret;
1287
1288 return count;
1289}
1290static DEVICE_ATTR_RW(driver_override);
1291
1292static struct attribute *platform_dev_attrs[] = {
1293 &dev_attr_modalias.attr,
1294 &dev_attr_numa_node.attr,
1295 &dev_attr_driver_override.attr,
1296 NULL,
1297};
1298
1299static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1300 int n)
1301{
1302 struct device *dev = container_of(kobj, typeof(*dev), kobj);
1303
1304 if (a == &dev_attr_numa_node.attr &&
1305 dev_to_node(dev) == NUMA_NO_NODE)
1306 return 0;
1307
1308 return a->mode;
1309}
1310
1311static const struct attribute_group platform_dev_group = {
1312 .attrs = platform_dev_attrs,
1313 .is_visible = platform_dev_attrs_visible,
1314};
1315__ATTRIBUTE_GROUPS(platform_dev);
1316
1317
1318/**
1319 * platform_match - bind platform device to platform driver.
1320 * @dev: device.
1321 * @drv: driver.
1322 *
1323 * Platform device IDs are assumed to be encoded like this:
1324 * "<name><instance>", where <name> is a short description of the type of
1325 * device, like "pci" or "floppy", and <instance> is the enumerated
1326 * instance of the device, like '0' or '42'. Driver IDs are simply
1327 * "<name>". So, extract the <name> from the platform_device structure,
1328 * and compare it against the name of the driver. Return whether they match
1329 * or not.
1330 */
1331static int platform_match(struct device *dev, struct device_driver *drv)
1332{
1333 struct platform_device *pdev = to_platform_device(dev);
1334 struct platform_driver *pdrv = to_platform_driver(drv);
1335
1336 /* When driver_override is set, only bind to the matching driver */
1337 if (pdev->driver_override)
1338 return !strcmp(pdev->driver_override, drv->name);
1339
1340 /* Attempt an OF style match first */
1341 if (of_driver_match_device(dev, drv))
1342 return 1;
1343
1344 /* Then try ACPI style match */
1345 if (acpi_driver_match_device(dev, drv))
1346 return 1;
1347
1348 /* Then try to match against the id table */
1349 if (pdrv->id_table)
1350 return platform_match_id(pdrv->id_table, pdev) != NULL;
1351
1352 /* fall-back to driver name match */
1353 return (strcmp(pdev->name, drv->name) == 0);
1354}
1355
1356static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1357{
1358 struct platform_device *pdev = to_platform_device(dev);
1359 int rc;
1360
1361 /* Some devices have extra OF data and an OF-style MODALIAS */
1362 rc = of_device_uevent_modalias(dev, env);
1363 if (rc != -ENODEV)
1364 return rc;
1365
1366 rc = acpi_device_uevent_modalias(dev, env);
1367 if (rc != -ENODEV)
1368 return rc;
1369
1370 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1371 pdev->name);
1372 return 0;
1373}
1374
1375static int platform_probe(struct device *_dev)
1376{
1377 struct platform_driver *drv = to_platform_driver(_dev->driver);
1378 struct platform_device *dev = to_platform_device(_dev);
1379 int ret;
1380
1381 /*
1382 * A driver registered using platform_driver_probe() cannot be bound
1383 * again later because the probe function usually lives in __init code
1384 * and so is gone. For these drivers .probe is set to
1385 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1386 * clocks and PM domains for these to match the traditional behaviour.
1387 */
1388 if (unlikely(drv->probe == platform_probe_fail))
1389 return -ENXIO;
1390
1391 ret = of_clk_set_defaults(_dev->of_node, false);
1392 if (ret < 0)
1393 return ret;
1394
1395 ret = dev_pm_domain_attach(_dev, true);
1396 if (ret)
1397 goto out;
1398
1399 if (drv->probe) {
1400 ret = drv->probe(dev);
1401 if (ret)
1402 dev_pm_domain_detach(_dev, true);
1403 }
1404
1405out:
1406 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1407 dev_warn(_dev, "probe deferral not supported\n");
1408 ret = -ENXIO;
1409 }
1410
1411 return ret;
1412}
1413
1414static void platform_remove(struct device *_dev)
1415{
1416 struct platform_driver *drv = to_platform_driver(_dev->driver);
1417 struct platform_device *dev = to_platform_device(_dev);
1418
1419 if (drv->remove) {
1420 int ret = drv->remove(dev);
1421
1422 if (ret)
1423 dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1424 }
1425 dev_pm_domain_detach(_dev, true);
1426}
1427
1428static void platform_shutdown(struct device *_dev)
1429{
1430 struct platform_device *dev = to_platform_device(_dev);
1431 struct platform_driver *drv;
1432
1433 if (!_dev->driver)
1434 return;
1435
1436 drv = to_platform_driver(_dev->driver);
1437 if (drv->shutdown)
1438 drv->shutdown(dev);
1439}
1440
1441static int platform_dma_configure(struct device *dev)
1442{
1443 struct platform_driver *drv = to_platform_driver(dev->driver);
1444 enum dev_dma_attr attr;
1445 int ret = 0;
1446
1447 if (dev->of_node) {
1448 ret = of_dma_configure(dev, dev->of_node, true);
1449 } else if (has_acpi_companion(dev)) {
1450 attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1451 ret = acpi_dma_configure(dev, attr);
1452 }
1453
1454 if (!ret && !drv->driver_managed_dma) {
1455 ret = iommu_device_use_default_domain(dev);
1456 if (ret)
1457 arch_teardown_dma_ops(dev);
1458 }
1459
1460 return ret;
1461}
1462
1463static void platform_dma_cleanup(struct device *dev)
1464{
1465 struct platform_driver *drv = to_platform_driver(dev->driver);
1466
1467 if (!drv->driver_managed_dma)
1468 iommu_device_unuse_default_domain(dev);
1469}
1470
1471static const struct dev_pm_ops platform_dev_pm_ops = {
1472 SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
1473 USE_PLATFORM_PM_SLEEP_OPS
1474};
1475
1476struct bus_type platform_bus_type = {
1477 .name = "platform",
1478 .dev_groups = platform_dev_groups,
1479 .match = platform_match,
1480 .uevent = platform_uevent,
1481 .probe = platform_probe,
1482 .remove = platform_remove,
1483 .shutdown = platform_shutdown,
1484 .dma_configure = platform_dma_configure,
1485 .dma_cleanup = platform_dma_cleanup,
1486 .pm = &platform_dev_pm_ops,
1487};
1488EXPORT_SYMBOL_GPL(platform_bus_type);
1489
1490static inline int __platform_match(struct device *dev, const void *drv)
1491{
1492 return platform_match(dev, (struct device_driver *)drv);
1493}
1494
1495/**
1496 * platform_find_device_by_driver - Find a platform device with a given
1497 * driver.
1498 * @start: The device to start the search from.
1499 * @drv: The device driver to look for.
1500 */
1501struct device *platform_find_device_by_driver(struct device *start,
1502 const struct device_driver *drv)
1503{
1504 return bus_find_device(&platform_bus_type, start, drv,
1505 __platform_match);
1506}
1507EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1508
1509void __weak __init early_platform_cleanup(void) { }
1510
1511int __init platform_bus_init(void)
1512{
1513 int error;
1514
1515 early_platform_cleanup();
1516
1517 error = device_register(&platform_bus);
1518 if (error) {
1519 put_device(&platform_bus);
1520 return error;
1521 }
1522 error = bus_register(&platform_bus_type);
1523 if (error)
1524 device_unregister(&platform_bus);
1525 of_platform_register_reconfig_notifier();
1526 return error;
1527}
1/*
2 * platform.c - platform 'pseudo' bus for legacy devices
3 *
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
6 *
7 * This file is released under the GPLv2
8 *
9 * Please see Documentation/driver-model/platform.txt for more
10 * information.
11 */
12
13#include <linux/string.h>
14#include <linux/platform_device.h>
15#include <linux/of_device.h>
16#include <linux/of_irq.h>
17#include <linux/module.h>
18#include <linux/init.h>
19#include <linux/dma-mapping.h>
20#include <linux/bootmem.h>
21#include <linux/err.h>
22#include <linux/slab.h>
23#include <linux/pm_runtime.h>
24#include <linux/pm_domain.h>
25#include <linux/idr.h>
26#include <linux/acpi.h>
27#include <linux/clk/clk-conf.h>
28#include <linux/limits.h>
29#include <linux/property.h>
30
31#include "base.h"
32#include "power/power.h"
33
34/* For automatically allocated device IDs */
35static DEFINE_IDA(platform_devid_ida);
36
37struct device platform_bus = {
38 .init_name = "platform",
39};
40EXPORT_SYMBOL_GPL(platform_bus);
41
42/**
43 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
44 * @pdev: platform device
45 *
46 * This is called before platform_device_add() such that any pdev_archdata may
47 * be setup before the platform_notifier is called. So if a user needs to
48 * manipulate any relevant information in the pdev_archdata they can do:
49 *
50 * platform_device_alloc()
51 * ... manipulate ...
52 * platform_device_add()
53 *
54 * And if they don't care they can just call platform_device_register() and
55 * everything will just work out.
56 */
57void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
58{
59}
60
61/**
62 * platform_get_resource - get a resource for a device
63 * @dev: platform device
64 * @type: resource type
65 * @num: resource index
66 */
67struct resource *platform_get_resource(struct platform_device *dev,
68 unsigned int type, unsigned int num)
69{
70 int i;
71
72 for (i = 0; i < dev->num_resources; i++) {
73 struct resource *r = &dev->resource[i];
74
75 if (type == resource_type(r) && num-- == 0)
76 return r;
77 }
78 return NULL;
79}
80EXPORT_SYMBOL_GPL(platform_get_resource);
81
82/**
83 * platform_get_irq - get an IRQ for a device
84 * @dev: platform device
85 * @num: IRQ number index
86 */
87int platform_get_irq(struct platform_device *dev, unsigned int num)
88{
89#ifdef CONFIG_SPARC
90 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
91 if (!dev || num >= dev->archdata.num_irqs)
92 return -ENXIO;
93 return dev->archdata.irqs[num];
94#else
95 struct resource *r;
96 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
97 int ret;
98
99 ret = of_irq_get(dev->dev.of_node, num);
100 if (ret > 0 || ret == -EPROBE_DEFER)
101 return ret;
102 }
103
104 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
105 /*
106 * The resources may pass trigger flags to the irqs that need
107 * to be set up. It so happens that the trigger flags for
108 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
109 * settings.
110 */
111 if (r && r->flags & IORESOURCE_BITS) {
112 struct irq_data *irqd;
113
114 irqd = irq_get_irq_data(r->start);
115 if (!irqd)
116 return -ENXIO;
117 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
118 }
119
120 return r ? r->start : -ENXIO;
121#endif
122}
123EXPORT_SYMBOL_GPL(platform_get_irq);
124
125/**
126 * platform_irq_count - Count the number of IRQs a platform device uses
127 * @dev: platform device
128 *
129 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
130 */
131int platform_irq_count(struct platform_device *dev)
132{
133 int ret, nr = 0;
134
135 while ((ret = platform_get_irq(dev, nr)) >= 0)
136 nr++;
137
138 if (ret == -EPROBE_DEFER)
139 return ret;
140
141 return nr;
142}
143EXPORT_SYMBOL_GPL(platform_irq_count);
144
145/**
146 * platform_get_resource_byname - get a resource for a device by name
147 * @dev: platform device
148 * @type: resource type
149 * @name: resource name
150 */
151struct resource *platform_get_resource_byname(struct platform_device *dev,
152 unsigned int type,
153 const char *name)
154{
155 int i;
156
157 for (i = 0; i < dev->num_resources; i++) {
158 struct resource *r = &dev->resource[i];
159
160 if (unlikely(!r->name))
161 continue;
162
163 if (type == resource_type(r) && !strcmp(r->name, name))
164 return r;
165 }
166 return NULL;
167}
168EXPORT_SYMBOL_GPL(platform_get_resource_byname);
169
170/**
171 * platform_get_irq_byname - get an IRQ for a device by name
172 * @dev: platform device
173 * @name: IRQ name
174 */
175int platform_get_irq_byname(struct platform_device *dev, const char *name)
176{
177 struct resource *r;
178
179 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
180 int ret;
181
182 ret = of_irq_get_byname(dev->dev.of_node, name);
183 if (ret > 0 || ret == -EPROBE_DEFER)
184 return ret;
185 }
186
187 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
188 return r ? r->start : -ENXIO;
189}
190EXPORT_SYMBOL_GPL(platform_get_irq_byname);
191
192/**
193 * platform_add_devices - add a numbers of platform devices
194 * @devs: array of platform devices to add
195 * @num: number of platform devices in array
196 */
197int platform_add_devices(struct platform_device **devs, int num)
198{
199 int i, ret = 0;
200
201 for (i = 0; i < num; i++) {
202 ret = platform_device_register(devs[i]);
203 if (ret) {
204 while (--i >= 0)
205 platform_device_unregister(devs[i]);
206 break;
207 }
208 }
209
210 return ret;
211}
212EXPORT_SYMBOL_GPL(platform_add_devices);
213
214struct platform_object {
215 struct platform_device pdev;
216 char name[];
217};
218
219/**
220 * platform_device_put - destroy a platform device
221 * @pdev: platform device to free
222 *
223 * Free all memory associated with a platform device. This function must
224 * _only_ be externally called in error cases. All other usage is a bug.
225 */
226void platform_device_put(struct platform_device *pdev)
227{
228 if (pdev)
229 put_device(&pdev->dev);
230}
231EXPORT_SYMBOL_GPL(platform_device_put);
232
233static void platform_device_release(struct device *dev)
234{
235 struct platform_object *pa = container_of(dev, struct platform_object,
236 pdev.dev);
237
238 of_device_node_put(&pa->pdev.dev);
239 kfree(pa->pdev.dev.platform_data);
240 kfree(pa->pdev.mfd_cell);
241 kfree(pa->pdev.resource);
242 kfree(pa->pdev.driver_override);
243 kfree(pa);
244}
245
246/**
247 * platform_device_alloc - create a platform device
248 * @name: base name of the device we're adding
249 * @id: instance id
250 *
251 * Create a platform device object which can have other objects attached
252 * to it, and which will have attached objects freed when it is released.
253 */
254struct platform_device *platform_device_alloc(const char *name, int id)
255{
256 struct platform_object *pa;
257
258 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
259 if (pa) {
260 strcpy(pa->name, name);
261 pa->pdev.name = pa->name;
262 pa->pdev.id = id;
263 device_initialize(&pa->pdev.dev);
264 pa->pdev.dev.release = platform_device_release;
265 arch_setup_pdev_archdata(&pa->pdev);
266 }
267
268 return pa ? &pa->pdev : NULL;
269}
270EXPORT_SYMBOL_GPL(platform_device_alloc);
271
272/**
273 * platform_device_add_resources - add resources to a platform device
274 * @pdev: platform device allocated by platform_device_alloc to add resources to
275 * @res: set of resources that needs to be allocated for the device
276 * @num: number of resources
277 *
278 * Add a copy of the resources to the platform device. The memory
279 * associated with the resources will be freed when the platform device is
280 * released.
281 */
282int platform_device_add_resources(struct platform_device *pdev,
283 const struct resource *res, unsigned int num)
284{
285 struct resource *r = NULL;
286
287 if (res) {
288 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
289 if (!r)
290 return -ENOMEM;
291 }
292
293 kfree(pdev->resource);
294 pdev->resource = r;
295 pdev->num_resources = num;
296 return 0;
297}
298EXPORT_SYMBOL_GPL(platform_device_add_resources);
299
300/**
301 * platform_device_add_data - add platform-specific data to a platform device
302 * @pdev: platform device allocated by platform_device_alloc to add resources to
303 * @data: platform specific data for this platform device
304 * @size: size of platform specific data
305 *
306 * Add a copy of platform specific data to the platform device's
307 * platform_data pointer. The memory associated with the platform data
308 * will be freed when the platform device is released.
309 */
310int platform_device_add_data(struct platform_device *pdev, const void *data,
311 size_t size)
312{
313 void *d = NULL;
314
315 if (data) {
316 d = kmemdup(data, size, GFP_KERNEL);
317 if (!d)
318 return -ENOMEM;
319 }
320
321 kfree(pdev->dev.platform_data);
322 pdev->dev.platform_data = d;
323 return 0;
324}
325EXPORT_SYMBOL_GPL(platform_device_add_data);
326
327/**
328 * platform_device_add_properties - add built-in properties to a platform device
329 * @pdev: platform device to add properties to
330 * @properties: null terminated array of properties to add
331 *
332 * The function will take deep copy of @properties and attach the copy to the
333 * platform device. The memory associated with properties will be freed when the
334 * platform device is released.
335 */
336int platform_device_add_properties(struct platform_device *pdev,
337 struct property_entry *properties)
338{
339 return device_add_properties(&pdev->dev, properties);
340}
341EXPORT_SYMBOL_GPL(platform_device_add_properties);
342
343/**
344 * platform_device_add - add a platform device to device hierarchy
345 * @pdev: platform device we're adding
346 *
347 * This is part 2 of platform_device_register(), though may be called
348 * separately _iff_ pdev was allocated by platform_device_alloc().
349 */
350int platform_device_add(struct platform_device *pdev)
351{
352 int i, ret;
353
354 if (!pdev)
355 return -EINVAL;
356
357 if (!pdev->dev.parent)
358 pdev->dev.parent = &platform_bus;
359
360 pdev->dev.bus = &platform_bus_type;
361
362 switch (pdev->id) {
363 default:
364 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
365 break;
366 case PLATFORM_DEVID_NONE:
367 dev_set_name(&pdev->dev, "%s", pdev->name);
368 break;
369 case PLATFORM_DEVID_AUTO:
370 /*
371 * Automatically allocated device ID. We mark it as such so
372 * that we remember it must be freed, and we append a suffix
373 * to avoid namespace collision with explicit IDs.
374 */
375 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
376 if (ret < 0)
377 goto err_out;
378 pdev->id = ret;
379 pdev->id_auto = true;
380 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
381 break;
382 }
383
384 for (i = 0; i < pdev->num_resources; i++) {
385 struct resource *p, *r = &pdev->resource[i];
386
387 if (r->name == NULL)
388 r->name = dev_name(&pdev->dev);
389
390 p = r->parent;
391 if (!p) {
392 if (resource_type(r) == IORESOURCE_MEM)
393 p = &iomem_resource;
394 else if (resource_type(r) == IORESOURCE_IO)
395 p = &ioport_resource;
396 }
397
398 if (p && insert_resource(p, r)) {
399 dev_err(&pdev->dev, "failed to claim resource %d\n", i);
400 ret = -EBUSY;
401 goto failed;
402 }
403 }
404
405 pr_debug("Registering platform device '%s'. Parent at %s\n",
406 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
407
408 ret = device_add(&pdev->dev);
409 if (ret == 0)
410 return ret;
411
412 failed:
413 if (pdev->id_auto) {
414 ida_simple_remove(&platform_devid_ida, pdev->id);
415 pdev->id = PLATFORM_DEVID_AUTO;
416 }
417
418 while (--i >= 0) {
419 struct resource *r = &pdev->resource[i];
420 if (r->parent)
421 release_resource(r);
422 }
423
424 err_out:
425 return ret;
426}
427EXPORT_SYMBOL_GPL(platform_device_add);
428
429/**
430 * platform_device_del - remove a platform-level device
431 * @pdev: platform device we're removing
432 *
433 * Note that this function will also release all memory- and port-based
434 * resources owned by the device (@dev->resource). This function must
435 * _only_ be externally called in error cases. All other usage is a bug.
436 */
437void platform_device_del(struct platform_device *pdev)
438{
439 int i;
440
441 if (pdev) {
442 device_remove_properties(&pdev->dev);
443 device_del(&pdev->dev);
444
445 if (pdev->id_auto) {
446 ida_simple_remove(&platform_devid_ida, pdev->id);
447 pdev->id = PLATFORM_DEVID_AUTO;
448 }
449
450 for (i = 0; i < pdev->num_resources; i++) {
451 struct resource *r = &pdev->resource[i];
452 if (r->parent)
453 release_resource(r);
454 }
455 }
456}
457EXPORT_SYMBOL_GPL(platform_device_del);
458
459/**
460 * platform_device_register - add a platform-level device
461 * @pdev: platform device we're adding
462 */
463int platform_device_register(struct platform_device *pdev)
464{
465 device_initialize(&pdev->dev);
466 arch_setup_pdev_archdata(pdev);
467 return platform_device_add(pdev);
468}
469EXPORT_SYMBOL_GPL(platform_device_register);
470
471/**
472 * platform_device_unregister - unregister a platform-level device
473 * @pdev: platform device we're unregistering
474 *
475 * Unregistration is done in 2 steps. First we release all resources
476 * and remove it from the subsystem, then we drop reference count by
477 * calling platform_device_put().
478 */
479void platform_device_unregister(struct platform_device *pdev)
480{
481 platform_device_del(pdev);
482 platform_device_put(pdev);
483}
484EXPORT_SYMBOL_GPL(platform_device_unregister);
485
486/**
487 * platform_device_register_full - add a platform-level device with
488 * resources and platform-specific data
489 *
490 * @pdevinfo: data used to create device
491 *
492 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
493 */
494struct platform_device *platform_device_register_full(
495 const struct platform_device_info *pdevinfo)
496{
497 int ret = -ENOMEM;
498 struct platform_device *pdev;
499
500 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
501 if (!pdev)
502 goto err_alloc;
503
504 pdev->dev.parent = pdevinfo->parent;
505 pdev->dev.fwnode = pdevinfo->fwnode;
506
507 if (pdevinfo->dma_mask) {
508 /*
509 * This memory isn't freed when the device is put,
510 * I don't have a nice idea for that though. Conceptually
511 * dma_mask in struct device should not be a pointer.
512 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
513 */
514 pdev->dev.dma_mask =
515 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
516 if (!pdev->dev.dma_mask)
517 goto err;
518
519 *pdev->dev.dma_mask = pdevinfo->dma_mask;
520 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
521 }
522
523 ret = platform_device_add_resources(pdev,
524 pdevinfo->res, pdevinfo->num_res);
525 if (ret)
526 goto err;
527
528 ret = platform_device_add_data(pdev,
529 pdevinfo->data, pdevinfo->size_data);
530 if (ret)
531 goto err;
532
533 if (pdevinfo->properties) {
534 ret = platform_device_add_properties(pdev,
535 pdevinfo->properties);
536 if (ret)
537 goto err;
538 }
539
540 ret = platform_device_add(pdev);
541 if (ret) {
542err:
543 ACPI_COMPANION_SET(&pdev->dev, NULL);
544 kfree(pdev->dev.dma_mask);
545
546err_alloc:
547 platform_device_put(pdev);
548 return ERR_PTR(ret);
549 }
550
551 return pdev;
552}
553EXPORT_SYMBOL_GPL(platform_device_register_full);
554
555static int platform_drv_probe(struct device *_dev)
556{
557 struct platform_driver *drv = to_platform_driver(_dev->driver);
558 struct platform_device *dev = to_platform_device(_dev);
559 int ret;
560
561 ret = of_clk_set_defaults(_dev->of_node, false);
562 if (ret < 0)
563 return ret;
564
565 ret = dev_pm_domain_attach(_dev, true);
566 if (ret != -EPROBE_DEFER) {
567 if (drv->probe) {
568 ret = drv->probe(dev);
569 if (ret)
570 dev_pm_domain_detach(_dev, true);
571 } else {
572 /* don't fail if just dev_pm_domain_attach failed */
573 ret = 0;
574 }
575 }
576
577 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
578 dev_warn(_dev, "probe deferral not supported\n");
579 ret = -ENXIO;
580 }
581
582 return ret;
583}
584
585static int platform_drv_probe_fail(struct device *_dev)
586{
587 return -ENXIO;
588}
589
590static int platform_drv_remove(struct device *_dev)
591{
592 struct platform_driver *drv = to_platform_driver(_dev->driver);
593 struct platform_device *dev = to_platform_device(_dev);
594 int ret = 0;
595
596 if (drv->remove)
597 ret = drv->remove(dev);
598 dev_pm_domain_detach(_dev, true);
599
600 return ret;
601}
602
603static void platform_drv_shutdown(struct device *_dev)
604{
605 struct platform_driver *drv = to_platform_driver(_dev->driver);
606 struct platform_device *dev = to_platform_device(_dev);
607
608 if (drv->shutdown)
609 drv->shutdown(dev);
610}
611
612/**
613 * __platform_driver_register - register a driver for platform-level devices
614 * @drv: platform driver structure
615 * @owner: owning module/driver
616 */
617int __platform_driver_register(struct platform_driver *drv,
618 struct module *owner)
619{
620 drv->driver.owner = owner;
621 drv->driver.bus = &platform_bus_type;
622 drv->driver.probe = platform_drv_probe;
623 drv->driver.remove = platform_drv_remove;
624 drv->driver.shutdown = platform_drv_shutdown;
625
626 return driver_register(&drv->driver);
627}
628EXPORT_SYMBOL_GPL(__platform_driver_register);
629
630/**
631 * platform_driver_unregister - unregister a driver for platform-level devices
632 * @drv: platform driver structure
633 */
634void platform_driver_unregister(struct platform_driver *drv)
635{
636 driver_unregister(&drv->driver);
637}
638EXPORT_SYMBOL_GPL(platform_driver_unregister);
639
640/**
641 * __platform_driver_probe - register driver for non-hotpluggable device
642 * @drv: platform driver structure
643 * @probe: the driver probe routine, probably from an __init section
644 * @module: module which will be the owner of the driver
645 *
646 * Use this instead of platform_driver_register() when you know the device
647 * is not hotpluggable and has already been registered, and you want to
648 * remove its run-once probe() infrastructure from memory after the driver
649 * has bound to the device.
650 *
651 * One typical use for this would be with drivers for controllers integrated
652 * into system-on-chip processors, where the controller devices have been
653 * configured as part of board setup.
654 *
655 * Note that this is incompatible with deferred probing.
656 *
657 * Returns zero if the driver registered and bound to a device, else returns
658 * a negative error code and with the driver not registered.
659 */
660int __init_or_module __platform_driver_probe(struct platform_driver *drv,
661 int (*probe)(struct platform_device *), struct module *module)
662{
663 int retval, code;
664
665 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
666 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
667 drv->driver.name, __func__);
668 return -EINVAL;
669 }
670
671 /*
672 * We have to run our probes synchronously because we check if
673 * we find any devices to bind to and exit with error if there
674 * are any.
675 */
676 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
677
678 /*
679 * Prevent driver from requesting probe deferral to avoid further
680 * futile probe attempts.
681 */
682 drv->prevent_deferred_probe = true;
683
684 /* make sure driver won't have bind/unbind attributes */
685 drv->driver.suppress_bind_attrs = true;
686
687 /* temporary section violation during probe() */
688 drv->probe = probe;
689 retval = code = __platform_driver_register(drv, module);
690
691 /*
692 * Fixup that section violation, being paranoid about code scanning
693 * the list of drivers in order to probe new devices. Check to see
694 * if the probe was successful, and make sure any forced probes of
695 * new devices fail.
696 */
697 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
698 drv->probe = NULL;
699 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
700 retval = -ENODEV;
701 drv->driver.probe = platform_drv_probe_fail;
702 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
703
704 if (code != retval)
705 platform_driver_unregister(drv);
706 return retval;
707}
708EXPORT_SYMBOL_GPL(__platform_driver_probe);
709
710/**
711 * __platform_create_bundle - register driver and create corresponding device
712 * @driver: platform driver structure
713 * @probe: the driver probe routine, probably from an __init section
714 * @res: set of resources that needs to be allocated for the device
715 * @n_res: number of resources
716 * @data: platform specific data for this platform device
717 * @size: size of platform specific data
718 * @module: module which will be the owner of the driver
719 *
720 * Use this in legacy-style modules that probe hardware directly and
721 * register a single platform device and corresponding platform driver.
722 *
723 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
724 */
725struct platform_device * __init_or_module __platform_create_bundle(
726 struct platform_driver *driver,
727 int (*probe)(struct platform_device *),
728 struct resource *res, unsigned int n_res,
729 const void *data, size_t size, struct module *module)
730{
731 struct platform_device *pdev;
732 int error;
733
734 pdev = platform_device_alloc(driver->driver.name, -1);
735 if (!pdev) {
736 error = -ENOMEM;
737 goto err_out;
738 }
739
740 error = platform_device_add_resources(pdev, res, n_res);
741 if (error)
742 goto err_pdev_put;
743
744 error = platform_device_add_data(pdev, data, size);
745 if (error)
746 goto err_pdev_put;
747
748 error = platform_device_add(pdev);
749 if (error)
750 goto err_pdev_put;
751
752 error = __platform_driver_probe(driver, probe, module);
753 if (error)
754 goto err_pdev_del;
755
756 return pdev;
757
758err_pdev_del:
759 platform_device_del(pdev);
760err_pdev_put:
761 platform_device_put(pdev);
762err_out:
763 return ERR_PTR(error);
764}
765EXPORT_SYMBOL_GPL(__platform_create_bundle);
766
767/**
768 * __platform_register_drivers - register an array of platform drivers
769 * @drivers: an array of drivers to register
770 * @count: the number of drivers to register
771 * @owner: module owning the drivers
772 *
773 * Registers platform drivers specified by an array. On failure to register a
774 * driver, all previously registered drivers will be unregistered. Callers of
775 * this API should use platform_unregister_drivers() to unregister drivers in
776 * the reverse order.
777 *
778 * Returns: 0 on success or a negative error code on failure.
779 */
780int __platform_register_drivers(struct platform_driver * const *drivers,
781 unsigned int count, struct module *owner)
782{
783 unsigned int i;
784 int err;
785
786 for (i = 0; i < count; i++) {
787 pr_debug("registering platform driver %ps\n", drivers[i]);
788
789 err = __platform_driver_register(drivers[i], owner);
790 if (err < 0) {
791 pr_err("failed to register platform driver %ps: %d\n",
792 drivers[i], err);
793 goto error;
794 }
795 }
796
797 return 0;
798
799error:
800 while (i--) {
801 pr_debug("unregistering platform driver %ps\n", drivers[i]);
802 platform_driver_unregister(drivers[i]);
803 }
804
805 return err;
806}
807EXPORT_SYMBOL_GPL(__platform_register_drivers);
808
809/**
810 * platform_unregister_drivers - unregister an array of platform drivers
811 * @drivers: an array of drivers to unregister
812 * @count: the number of drivers to unregister
813 *
814 * Unegisters platform drivers specified by an array. This is typically used
815 * to complement an earlier call to platform_register_drivers(). Drivers are
816 * unregistered in the reverse order in which they were registered.
817 */
818void platform_unregister_drivers(struct platform_driver * const *drivers,
819 unsigned int count)
820{
821 while (count--) {
822 pr_debug("unregistering platform driver %ps\n", drivers[count]);
823 platform_driver_unregister(drivers[count]);
824 }
825}
826EXPORT_SYMBOL_GPL(platform_unregister_drivers);
827
828/* modalias support enables more hands-off userspace setup:
829 * (a) environment variable lets new-style hotplug events work once system is
830 * fully running: "modprobe $MODALIAS"
831 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
832 * mishandled before system is fully running: "modprobe $(cat modalias)"
833 */
834static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
835 char *buf)
836{
837 struct platform_device *pdev = to_platform_device(dev);
838 int len;
839
840 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
841 if (len != -ENODEV)
842 return len;
843
844 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
845 if (len != -ENODEV)
846 return len;
847
848 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
849
850 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
851}
852static DEVICE_ATTR_RO(modalias);
853
854static ssize_t driver_override_store(struct device *dev,
855 struct device_attribute *attr,
856 const char *buf, size_t count)
857{
858 struct platform_device *pdev = to_platform_device(dev);
859 char *driver_override, *old = pdev->driver_override, *cp;
860
861 if (count > PATH_MAX)
862 return -EINVAL;
863
864 driver_override = kstrndup(buf, count, GFP_KERNEL);
865 if (!driver_override)
866 return -ENOMEM;
867
868 cp = strchr(driver_override, '\n');
869 if (cp)
870 *cp = '\0';
871
872 if (strlen(driver_override)) {
873 pdev->driver_override = driver_override;
874 } else {
875 kfree(driver_override);
876 pdev->driver_override = NULL;
877 }
878
879 kfree(old);
880
881 return count;
882}
883
884static ssize_t driver_override_show(struct device *dev,
885 struct device_attribute *attr, char *buf)
886{
887 struct platform_device *pdev = to_platform_device(dev);
888
889 return sprintf(buf, "%s\n", pdev->driver_override);
890}
891static DEVICE_ATTR_RW(driver_override);
892
893
894static struct attribute *platform_dev_attrs[] = {
895 &dev_attr_modalias.attr,
896 &dev_attr_driver_override.attr,
897 NULL,
898};
899ATTRIBUTE_GROUPS(platform_dev);
900
901static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
902{
903 struct platform_device *pdev = to_platform_device(dev);
904 int rc;
905
906 /* Some devices have extra OF data and an OF-style MODALIAS */
907 rc = of_device_uevent_modalias(dev, env);
908 if (rc != -ENODEV)
909 return rc;
910
911 rc = acpi_device_uevent_modalias(dev, env);
912 if (rc != -ENODEV)
913 return rc;
914
915 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
916 pdev->name);
917 return 0;
918}
919
920static const struct platform_device_id *platform_match_id(
921 const struct platform_device_id *id,
922 struct platform_device *pdev)
923{
924 while (id->name[0]) {
925 if (strcmp(pdev->name, id->name) == 0) {
926 pdev->id_entry = id;
927 return id;
928 }
929 id++;
930 }
931 return NULL;
932}
933
934/**
935 * platform_match - bind platform device to platform driver.
936 * @dev: device.
937 * @drv: driver.
938 *
939 * Platform device IDs are assumed to be encoded like this:
940 * "<name><instance>", where <name> is a short description of the type of
941 * device, like "pci" or "floppy", and <instance> is the enumerated
942 * instance of the device, like '0' or '42'. Driver IDs are simply
943 * "<name>". So, extract the <name> from the platform_device structure,
944 * and compare it against the name of the driver. Return whether they match
945 * or not.
946 */
947static int platform_match(struct device *dev, struct device_driver *drv)
948{
949 struct platform_device *pdev = to_platform_device(dev);
950 struct platform_driver *pdrv = to_platform_driver(drv);
951
952 /* When driver_override is set, only bind to the matching driver */
953 if (pdev->driver_override)
954 return !strcmp(pdev->driver_override, drv->name);
955
956 /* Attempt an OF style match first */
957 if (of_driver_match_device(dev, drv))
958 return 1;
959
960 /* Then try ACPI style match */
961 if (acpi_driver_match_device(dev, drv))
962 return 1;
963
964 /* Then try to match against the id table */
965 if (pdrv->id_table)
966 return platform_match_id(pdrv->id_table, pdev) != NULL;
967
968 /* fall-back to driver name match */
969 return (strcmp(pdev->name, drv->name) == 0);
970}
971
972#ifdef CONFIG_PM_SLEEP
973
974static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
975{
976 struct platform_driver *pdrv = to_platform_driver(dev->driver);
977 struct platform_device *pdev = to_platform_device(dev);
978 int ret = 0;
979
980 if (dev->driver && pdrv->suspend)
981 ret = pdrv->suspend(pdev, mesg);
982
983 return ret;
984}
985
986static int platform_legacy_resume(struct device *dev)
987{
988 struct platform_driver *pdrv = to_platform_driver(dev->driver);
989 struct platform_device *pdev = to_platform_device(dev);
990 int ret = 0;
991
992 if (dev->driver && pdrv->resume)
993 ret = pdrv->resume(pdev);
994
995 return ret;
996}
997
998#endif /* CONFIG_PM_SLEEP */
999
1000#ifdef CONFIG_SUSPEND
1001
1002int platform_pm_suspend(struct device *dev)
1003{
1004 struct device_driver *drv = dev->driver;
1005 int ret = 0;
1006
1007 if (!drv)
1008 return 0;
1009
1010 if (drv->pm) {
1011 if (drv->pm->suspend)
1012 ret = drv->pm->suspend(dev);
1013 } else {
1014 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1015 }
1016
1017 return ret;
1018}
1019
1020int platform_pm_resume(struct device *dev)
1021{
1022 struct device_driver *drv = dev->driver;
1023 int ret = 0;
1024
1025 if (!drv)
1026 return 0;
1027
1028 if (drv->pm) {
1029 if (drv->pm->resume)
1030 ret = drv->pm->resume(dev);
1031 } else {
1032 ret = platform_legacy_resume(dev);
1033 }
1034
1035 return ret;
1036}
1037
1038#endif /* CONFIG_SUSPEND */
1039
1040#ifdef CONFIG_HIBERNATE_CALLBACKS
1041
1042int platform_pm_freeze(struct device *dev)
1043{
1044 struct device_driver *drv = dev->driver;
1045 int ret = 0;
1046
1047 if (!drv)
1048 return 0;
1049
1050 if (drv->pm) {
1051 if (drv->pm->freeze)
1052 ret = drv->pm->freeze(dev);
1053 } else {
1054 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1055 }
1056
1057 return ret;
1058}
1059
1060int platform_pm_thaw(struct device *dev)
1061{
1062 struct device_driver *drv = dev->driver;
1063 int ret = 0;
1064
1065 if (!drv)
1066 return 0;
1067
1068 if (drv->pm) {
1069 if (drv->pm->thaw)
1070 ret = drv->pm->thaw(dev);
1071 } else {
1072 ret = platform_legacy_resume(dev);
1073 }
1074
1075 return ret;
1076}
1077
1078int platform_pm_poweroff(struct device *dev)
1079{
1080 struct device_driver *drv = dev->driver;
1081 int ret = 0;
1082
1083 if (!drv)
1084 return 0;
1085
1086 if (drv->pm) {
1087 if (drv->pm->poweroff)
1088 ret = drv->pm->poweroff(dev);
1089 } else {
1090 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1091 }
1092
1093 return ret;
1094}
1095
1096int platform_pm_restore(struct device *dev)
1097{
1098 struct device_driver *drv = dev->driver;
1099 int ret = 0;
1100
1101 if (!drv)
1102 return 0;
1103
1104 if (drv->pm) {
1105 if (drv->pm->restore)
1106 ret = drv->pm->restore(dev);
1107 } else {
1108 ret = platform_legacy_resume(dev);
1109 }
1110
1111 return ret;
1112}
1113
1114#endif /* CONFIG_HIBERNATE_CALLBACKS */
1115
1116static const struct dev_pm_ops platform_dev_pm_ops = {
1117 .runtime_suspend = pm_generic_runtime_suspend,
1118 .runtime_resume = pm_generic_runtime_resume,
1119 USE_PLATFORM_PM_SLEEP_OPS
1120};
1121
1122struct bus_type platform_bus_type = {
1123 .name = "platform",
1124 .dev_groups = platform_dev_groups,
1125 .match = platform_match,
1126 .uevent = platform_uevent,
1127 .pm = &platform_dev_pm_ops,
1128};
1129EXPORT_SYMBOL_GPL(platform_bus_type);
1130
1131int __init platform_bus_init(void)
1132{
1133 int error;
1134
1135 early_platform_cleanup();
1136
1137 error = device_register(&platform_bus);
1138 if (error)
1139 return error;
1140 error = bus_register(&platform_bus_type);
1141 if (error)
1142 device_unregister(&platform_bus);
1143 of_platform_register_reconfig_notifier();
1144 return error;
1145}
1146
1147#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1148u64 dma_get_required_mask(struct device *dev)
1149{
1150 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1151 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1152 u64 mask;
1153
1154 if (!high_totalram) {
1155 /* convert to mask just covering totalram */
1156 low_totalram = (1 << (fls(low_totalram) - 1));
1157 low_totalram += low_totalram - 1;
1158 mask = low_totalram;
1159 } else {
1160 high_totalram = (1 << (fls(high_totalram) - 1));
1161 high_totalram += high_totalram - 1;
1162 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1163 }
1164 return mask;
1165}
1166EXPORT_SYMBOL_GPL(dma_get_required_mask);
1167#endif
1168
1169static __initdata LIST_HEAD(early_platform_driver_list);
1170static __initdata LIST_HEAD(early_platform_device_list);
1171
1172/**
1173 * early_platform_driver_register - register early platform driver
1174 * @epdrv: early_platform driver structure
1175 * @buf: string passed from early_param()
1176 *
1177 * Helper function for early_platform_init() / early_platform_init_buffer()
1178 */
1179int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1180 char *buf)
1181{
1182 char *tmp;
1183 int n;
1184
1185 /* Simply add the driver to the end of the global list.
1186 * Drivers will by default be put on the list in compiled-in order.
1187 */
1188 if (!epdrv->list.next) {
1189 INIT_LIST_HEAD(&epdrv->list);
1190 list_add_tail(&epdrv->list, &early_platform_driver_list);
1191 }
1192
1193 /* If the user has specified device then make sure the driver
1194 * gets prioritized. The driver of the last device specified on
1195 * command line will be put first on the list.
1196 */
1197 n = strlen(epdrv->pdrv->driver.name);
1198 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1199 list_move(&epdrv->list, &early_platform_driver_list);
1200
1201 /* Allow passing parameters after device name */
1202 if (buf[n] == '\0' || buf[n] == ',')
1203 epdrv->requested_id = -1;
1204 else {
1205 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1206 &tmp, 10);
1207
1208 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1209 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1210 n = 0;
1211 } else
1212 n += strcspn(&buf[n + 1], ",") + 1;
1213 }
1214
1215 if (buf[n] == ',')
1216 n++;
1217
1218 if (epdrv->bufsize) {
1219 memcpy(epdrv->buffer, &buf[n],
1220 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1221 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1222 }
1223 }
1224
1225 return 0;
1226}
1227
1228/**
1229 * early_platform_add_devices - adds a number of early platform devices
1230 * @devs: array of early platform devices to add
1231 * @num: number of early platform devices in array
1232 *
1233 * Used by early architecture code to register early platform devices and
1234 * their platform data.
1235 */
1236void __init early_platform_add_devices(struct platform_device **devs, int num)
1237{
1238 struct device *dev;
1239 int i;
1240
1241 /* simply add the devices to list */
1242 for (i = 0; i < num; i++) {
1243 dev = &devs[i]->dev;
1244
1245 if (!dev->devres_head.next) {
1246 pm_runtime_early_init(dev);
1247 INIT_LIST_HEAD(&dev->devres_head);
1248 list_add_tail(&dev->devres_head,
1249 &early_platform_device_list);
1250 }
1251 }
1252}
1253
1254/**
1255 * early_platform_driver_register_all - register early platform drivers
1256 * @class_str: string to identify early platform driver class
1257 *
1258 * Used by architecture code to register all early platform drivers
1259 * for a certain class. If omitted then only early platform drivers
1260 * with matching kernel command line class parameters will be registered.
1261 */
1262void __init early_platform_driver_register_all(char *class_str)
1263{
1264 /* The "class_str" parameter may or may not be present on the kernel
1265 * command line. If it is present then there may be more than one
1266 * matching parameter.
1267 *
1268 * Since we register our early platform drivers using early_param()
1269 * we need to make sure that they also get registered in the case
1270 * when the parameter is missing from the kernel command line.
1271 *
1272 * We use parse_early_options() to make sure the early_param() gets
1273 * called at least once. The early_param() may be called more than
1274 * once since the name of the preferred device may be specified on
1275 * the kernel command line. early_platform_driver_register() handles
1276 * this case for us.
1277 */
1278 parse_early_options(class_str);
1279}
1280
1281/**
1282 * early_platform_match - find early platform device matching driver
1283 * @epdrv: early platform driver structure
1284 * @id: id to match against
1285 */
1286static struct platform_device * __init
1287early_platform_match(struct early_platform_driver *epdrv, int id)
1288{
1289 struct platform_device *pd;
1290
1291 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1292 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1293 if (pd->id == id)
1294 return pd;
1295
1296 return NULL;
1297}
1298
1299/**
1300 * early_platform_left - check if early platform driver has matching devices
1301 * @epdrv: early platform driver structure
1302 * @id: return true if id or above exists
1303 */
1304static int __init early_platform_left(struct early_platform_driver *epdrv,
1305 int id)
1306{
1307 struct platform_device *pd;
1308
1309 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1310 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1311 if (pd->id >= id)
1312 return 1;
1313
1314 return 0;
1315}
1316
1317/**
1318 * early_platform_driver_probe_id - probe drivers matching class_str and id
1319 * @class_str: string to identify early platform driver class
1320 * @id: id to match against
1321 * @nr_probe: number of platform devices to successfully probe before exiting
1322 */
1323static int __init early_platform_driver_probe_id(char *class_str,
1324 int id,
1325 int nr_probe)
1326{
1327 struct early_platform_driver *epdrv;
1328 struct platform_device *match;
1329 int match_id;
1330 int n = 0;
1331 int left = 0;
1332
1333 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1334 /* only use drivers matching our class_str */
1335 if (strcmp(class_str, epdrv->class_str))
1336 continue;
1337
1338 if (id == -2) {
1339 match_id = epdrv->requested_id;
1340 left = 1;
1341
1342 } else {
1343 match_id = id;
1344 left += early_platform_left(epdrv, id);
1345
1346 /* skip requested id */
1347 switch (epdrv->requested_id) {
1348 case EARLY_PLATFORM_ID_ERROR:
1349 case EARLY_PLATFORM_ID_UNSET:
1350 break;
1351 default:
1352 if (epdrv->requested_id == id)
1353 match_id = EARLY_PLATFORM_ID_UNSET;
1354 }
1355 }
1356
1357 switch (match_id) {
1358 case EARLY_PLATFORM_ID_ERROR:
1359 pr_warn("%s: unable to parse %s parameter\n",
1360 class_str, epdrv->pdrv->driver.name);
1361 /* fall-through */
1362 case EARLY_PLATFORM_ID_UNSET:
1363 match = NULL;
1364 break;
1365 default:
1366 match = early_platform_match(epdrv, match_id);
1367 }
1368
1369 if (match) {
1370 /*
1371 * Set up a sensible init_name to enable
1372 * dev_name() and others to be used before the
1373 * rest of the driver core is initialized.
1374 */
1375 if (!match->dev.init_name && slab_is_available()) {
1376 if (match->id != -1)
1377 match->dev.init_name =
1378 kasprintf(GFP_KERNEL, "%s.%d",
1379 match->name,
1380 match->id);
1381 else
1382 match->dev.init_name =
1383 kasprintf(GFP_KERNEL, "%s",
1384 match->name);
1385
1386 if (!match->dev.init_name)
1387 return -ENOMEM;
1388 }
1389
1390 if (epdrv->pdrv->probe(match))
1391 pr_warn("%s: unable to probe %s early.\n",
1392 class_str, match->name);
1393 else
1394 n++;
1395 }
1396
1397 if (n >= nr_probe)
1398 break;
1399 }
1400
1401 if (left)
1402 return n;
1403 else
1404 return -ENODEV;
1405}
1406
1407/**
1408 * early_platform_driver_probe - probe a class of registered drivers
1409 * @class_str: string to identify early platform driver class
1410 * @nr_probe: number of platform devices to successfully probe before exiting
1411 * @user_only: only probe user specified early platform devices
1412 *
1413 * Used by architecture code to probe registered early platform drivers
1414 * within a certain class. For probe to happen a registered early platform
1415 * device matching a registered early platform driver is needed.
1416 */
1417int __init early_platform_driver_probe(char *class_str,
1418 int nr_probe,
1419 int user_only)
1420{
1421 int k, n, i;
1422
1423 n = 0;
1424 for (i = -2; n < nr_probe; i++) {
1425 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1426
1427 if (k < 0)
1428 break;
1429
1430 n += k;
1431
1432 if (user_only)
1433 break;
1434 }
1435
1436 return n;
1437}
1438
1439/**
1440 * early_platform_cleanup - clean up early platform code
1441 */
1442void __init early_platform_cleanup(void)
1443{
1444 struct platform_device *pd, *pd2;
1445
1446 /* clean up the devres list used to chain devices */
1447 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1448 dev.devres_head) {
1449 list_del(&pd->dev.devres_head);
1450 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1451 }
1452}
1453