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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 fwnode_handle *fwnode = dev_fwnode(&dev->dev);
182 struct resource *r;
183
184 if (is_of_node(fwnode)) {
185 ret = of_irq_get(to_of_node(fwnode), num);
186 if (ret > 0 || ret == -EPROBE_DEFER)
187 goto out;
188 }
189
190 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
191 if (is_acpi_device_node(fwnode)) {
192 if (r && r->flags & IORESOURCE_DISABLED) {
193 ret = acpi_irq_get(ACPI_HANDLE_FWNODE(fwnode), num, r);
194 if (ret)
195 goto out;
196 }
197 }
198
199 /*
200 * The resources may pass trigger flags to the irqs that need
201 * to be set up. It so happens that the trigger flags for
202 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
203 * settings.
204 */
205 if (r && r->flags & IORESOURCE_BITS) {
206 struct irq_data *irqd;
207
208 irqd = irq_get_irq_data(r->start);
209 if (!irqd)
210 goto out_not_found;
211 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
212 }
213
214 if (r) {
215 ret = r->start;
216 goto out;
217 }
218
219 /*
220 * For the index 0 interrupt, allow falling back to GpioInt
221 * resources. While a device could have both Interrupt and GpioInt
222 * resources, making this fallback ambiguous, in many common cases
223 * the device will only expose one IRQ, and this fallback
224 * allows a common code path across either kind of resource.
225 */
226 if (num == 0 && is_acpi_device_node(fwnode)) {
227 ret = acpi_dev_gpio_irq_get(to_acpi_device_node(fwnode), num);
228 /* Our callers expect -ENXIO for missing IRQs. */
229 if (ret >= 0 || ret == -EPROBE_DEFER)
230 goto out;
231 }
232
233#endif
234out_not_found:
235 ret = -ENXIO;
236out:
237 if (WARN(!ret, "0 is an invalid IRQ number\n"))
238 return -EINVAL;
239 return ret;
240}
241EXPORT_SYMBOL_GPL(platform_get_irq_optional);
242
243/**
244 * platform_get_irq - get an IRQ for a device
245 * @dev: platform device
246 * @num: IRQ number index
247 *
248 * Gets an IRQ for a platform device and prints an error message if finding the
249 * IRQ fails. Device drivers should check the return value for errors so as to
250 * not pass a negative integer value to the request_irq() APIs.
251 *
252 * For example::
253 *
254 * int irq = platform_get_irq(pdev, 0);
255 * if (irq < 0)
256 * return irq;
257 *
258 * Return: non-zero IRQ number on success, negative error number on failure.
259 */
260int platform_get_irq(struct platform_device *dev, unsigned int num)
261{
262 int ret;
263
264 ret = platform_get_irq_optional(dev, num);
265 if (ret < 0)
266 return dev_err_probe(&dev->dev, ret,
267 "IRQ index %u not found\n", num);
268
269 return ret;
270}
271EXPORT_SYMBOL_GPL(platform_get_irq);
272
273/**
274 * platform_irq_count - Count the number of IRQs a platform device uses
275 * @dev: platform device
276 *
277 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
278 */
279int platform_irq_count(struct platform_device *dev)
280{
281 int ret, nr = 0;
282
283 while ((ret = platform_get_irq_optional(dev, nr)) >= 0)
284 nr++;
285
286 if (ret == -EPROBE_DEFER)
287 return ret;
288
289 return nr;
290}
291EXPORT_SYMBOL_GPL(platform_irq_count);
292
293struct irq_affinity_devres {
294 unsigned int count;
295 unsigned int irq[] __counted_by(count);
296};
297
298static void platform_disable_acpi_irq(struct platform_device *pdev, int index)
299{
300 struct resource *r;
301
302 r = platform_get_resource(pdev, IORESOURCE_IRQ, index);
303 if (r)
304 irqresource_disabled(r, 0);
305}
306
307static void devm_platform_get_irqs_affinity_release(struct device *dev,
308 void *res)
309{
310 struct irq_affinity_devres *ptr = res;
311 int i;
312
313 for (i = 0; i < ptr->count; i++) {
314 irq_dispose_mapping(ptr->irq[i]);
315
316 if (is_acpi_device_node(dev_fwnode(dev)))
317 platform_disable_acpi_irq(to_platform_device(dev), i);
318 }
319}
320
321/**
322 * devm_platform_get_irqs_affinity - devm method to get a set of IRQs for a
323 * device using an interrupt affinity descriptor
324 * @dev: platform device pointer
325 * @affd: affinity descriptor
326 * @minvec: minimum count of interrupt vectors
327 * @maxvec: maximum count of interrupt vectors
328 * @irqs: pointer holder for IRQ numbers
329 *
330 * Gets a set of IRQs for a platform device, and updates IRQ afffinty according
331 * to the passed affinity descriptor
332 *
333 * Return: Number of vectors on success, negative error number on failure.
334 */
335int devm_platform_get_irqs_affinity(struct platform_device *dev,
336 struct irq_affinity *affd,
337 unsigned int minvec,
338 unsigned int maxvec,
339 int **irqs)
340{
341 struct irq_affinity_devres *ptr;
342 struct irq_affinity_desc *desc;
343 size_t size;
344 int i, ret, nvec;
345
346 if (!affd)
347 return -EPERM;
348
349 if (maxvec < minvec)
350 return -ERANGE;
351
352 nvec = platform_irq_count(dev);
353 if (nvec < 0)
354 return nvec;
355
356 if (nvec < minvec)
357 return -ENOSPC;
358
359 nvec = irq_calc_affinity_vectors(minvec, nvec, affd);
360 if (nvec < minvec)
361 return -ENOSPC;
362
363 if (nvec > maxvec)
364 nvec = maxvec;
365
366 size = sizeof(*ptr) + sizeof(unsigned int) * nvec;
367 ptr = devres_alloc(devm_platform_get_irqs_affinity_release, size,
368 GFP_KERNEL);
369 if (!ptr)
370 return -ENOMEM;
371
372 ptr->count = nvec;
373
374 for (i = 0; i < nvec; i++) {
375 int irq = platform_get_irq(dev, i);
376 if (irq < 0) {
377 ret = irq;
378 goto err_free_devres;
379 }
380 ptr->irq[i] = irq;
381 }
382
383 desc = irq_create_affinity_masks(nvec, affd);
384 if (!desc) {
385 ret = -ENOMEM;
386 goto err_free_devres;
387 }
388
389 for (i = 0; i < nvec; i++) {
390 ret = irq_update_affinity_desc(ptr->irq[i], &desc[i]);
391 if (ret) {
392 dev_err(&dev->dev, "failed to update irq%d affinity descriptor (%d)\n",
393 ptr->irq[i], ret);
394 goto err_free_desc;
395 }
396 }
397
398 devres_add(&dev->dev, ptr);
399
400 kfree(desc);
401
402 *irqs = ptr->irq;
403
404 return nvec;
405
406err_free_desc:
407 kfree(desc);
408err_free_devres:
409 devres_free(ptr);
410 return ret;
411}
412EXPORT_SYMBOL_GPL(devm_platform_get_irqs_affinity);
413
414/**
415 * platform_get_resource_byname - get a resource for a device by name
416 * @dev: platform device
417 * @type: resource type
418 * @name: resource name
419 */
420struct resource *platform_get_resource_byname(struct platform_device *dev,
421 unsigned int type,
422 const char *name)
423{
424 u32 i;
425
426 for (i = 0; i < dev->num_resources; i++) {
427 struct resource *r = &dev->resource[i];
428
429 if (unlikely(!r->name))
430 continue;
431
432 if (type == resource_type(r) && !strcmp(r->name, name))
433 return r;
434 }
435 return NULL;
436}
437EXPORT_SYMBOL_GPL(platform_get_resource_byname);
438
439static int __platform_get_irq_byname(struct platform_device *dev,
440 const char *name)
441{
442 struct resource *r;
443 int ret;
444
445 ret = fwnode_irq_get_byname(dev_fwnode(&dev->dev), name);
446 if (ret > 0 || ret == -EPROBE_DEFER)
447 return ret;
448
449 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
450 if (r) {
451 if (WARN(!r->start, "0 is an invalid IRQ number\n"))
452 return -EINVAL;
453 return r->start;
454 }
455
456 return -ENXIO;
457}
458
459/**
460 * platform_get_irq_byname - get an IRQ for a device by name
461 * @dev: platform device
462 * @name: IRQ name
463 *
464 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
465 *
466 * Return: non-zero IRQ number on success, negative error number on failure.
467 */
468int platform_get_irq_byname(struct platform_device *dev, const char *name)
469{
470 int ret;
471
472 ret = __platform_get_irq_byname(dev, name);
473 if (ret < 0)
474 return dev_err_probe(&dev->dev, ret, "IRQ %s not found\n",
475 name);
476 return ret;
477}
478EXPORT_SYMBOL_GPL(platform_get_irq_byname);
479
480/**
481 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
482 * @dev: platform device
483 * @name: IRQ name
484 *
485 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
486 * does not print an error message if an IRQ can not be obtained.
487 *
488 * Return: non-zero IRQ number on success, negative error number on failure.
489 */
490int platform_get_irq_byname_optional(struct platform_device *dev,
491 const char *name)
492{
493 return __platform_get_irq_byname(dev, name);
494}
495EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
496
497/**
498 * platform_add_devices - add a numbers of platform devices
499 * @devs: array of platform devices to add
500 * @num: number of platform devices in array
501 *
502 * Return: 0 on success, negative error number on failure.
503 */
504int platform_add_devices(struct platform_device **devs, int num)
505{
506 int i, ret = 0;
507
508 for (i = 0; i < num; i++) {
509 ret = platform_device_register(devs[i]);
510 if (ret) {
511 while (--i >= 0)
512 platform_device_unregister(devs[i]);
513 break;
514 }
515 }
516
517 return ret;
518}
519EXPORT_SYMBOL_GPL(platform_add_devices);
520
521struct platform_object {
522 struct platform_device pdev;
523 char name[];
524};
525
526/*
527 * Set up default DMA mask for platform devices if the they weren't
528 * previously set by the architecture / DT.
529 */
530static void setup_pdev_dma_masks(struct platform_device *pdev)
531{
532 pdev->dev.dma_parms = &pdev->dma_parms;
533
534 if (!pdev->dev.coherent_dma_mask)
535 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
536 if (!pdev->dev.dma_mask) {
537 pdev->platform_dma_mask = DMA_BIT_MASK(32);
538 pdev->dev.dma_mask = &pdev->platform_dma_mask;
539 }
540};
541
542/**
543 * platform_device_put - destroy a platform device
544 * @pdev: platform device to free
545 *
546 * Free all memory associated with a platform device. This function must
547 * _only_ be externally called in error cases. All other usage is a bug.
548 */
549void platform_device_put(struct platform_device *pdev)
550{
551 if (!IS_ERR_OR_NULL(pdev))
552 put_device(&pdev->dev);
553}
554EXPORT_SYMBOL_GPL(platform_device_put);
555
556static void platform_device_release(struct device *dev)
557{
558 struct platform_object *pa = container_of(dev, struct platform_object,
559 pdev.dev);
560
561 of_node_put(pa->pdev.dev.of_node);
562 kfree(pa->pdev.dev.platform_data);
563 kfree(pa->pdev.mfd_cell);
564 kfree(pa->pdev.resource);
565 kfree(pa->pdev.driver_override);
566 kfree(pa);
567}
568
569/**
570 * platform_device_alloc - create a platform device
571 * @name: base name of the device we're adding
572 * @id: instance id
573 *
574 * Create a platform device object which can have other objects attached
575 * to it, and which will have attached objects freed when it is released.
576 */
577struct platform_device *platform_device_alloc(const char *name, int id)
578{
579 struct platform_object *pa;
580
581 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
582 if (pa) {
583 strcpy(pa->name, name);
584 pa->pdev.name = pa->name;
585 pa->pdev.id = id;
586 device_initialize(&pa->pdev.dev);
587 pa->pdev.dev.release = platform_device_release;
588 setup_pdev_dma_masks(&pa->pdev);
589 }
590
591 return pa ? &pa->pdev : NULL;
592}
593EXPORT_SYMBOL_GPL(platform_device_alloc);
594
595/**
596 * platform_device_add_resources - add resources to a platform device
597 * @pdev: platform device allocated by platform_device_alloc to add resources to
598 * @res: set of resources that needs to be allocated for the device
599 * @num: number of resources
600 *
601 * Add a copy of the resources to the platform device. The memory
602 * associated with the resources will be freed when the platform device is
603 * released.
604 */
605int platform_device_add_resources(struct platform_device *pdev,
606 const struct resource *res, unsigned int num)
607{
608 struct resource *r = NULL;
609
610 if (res) {
611 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
612 if (!r)
613 return -ENOMEM;
614 }
615
616 kfree(pdev->resource);
617 pdev->resource = r;
618 pdev->num_resources = num;
619 return 0;
620}
621EXPORT_SYMBOL_GPL(platform_device_add_resources);
622
623/**
624 * platform_device_add_data - add platform-specific data to a platform device
625 * @pdev: platform device allocated by platform_device_alloc to add resources to
626 * @data: platform specific data for this platform device
627 * @size: size of platform specific data
628 *
629 * Add a copy of platform specific data to the platform device's
630 * platform_data pointer. The memory associated with the platform data
631 * will be freed when the platform device is released.
632 */
633int platform_device_add_data(struct platform_device *pdev, const void *data,
634 size_t size)
635{
636 void *d = NULL;
637
638 if (data) {
639 d = kmemdup(data, size, GFP_KERNEL);
640 if (!d)
641 return -ENOMEM;
642 }
643
644 kfree(pdev->dev.platform_data);
645 pdev->dev.platform_data = d;
646 return 0;
647}
648EXPORT_SYMBOL_GPL(platform_device_add_data);
649
650/**
651 * platform_device_add - add a platform device to device hierarchy
652 * @pdev: platform device we're adding
653 *
654 * This is part 2 of platform_device_register(), though may be called
655 * separately _iff_ pdev was allocated by platform_device_alloc().
656 */
657int platform_device_add(struct platform_device *pdev)
658{
659 struct device *dev = &pdev->dev;
660 u32 i;
661 int ret;
662
663 if (!dev->parent)
664 dev->parent = &platform_bus;
665
666 dev->bus = &platform_bus_type;
667
668 switch (pdev->id) {
669 default:
670 dev_set_name(dev, "%s.%d", pdev->name, pdev->id);
671 break;
672 case PLATFORM_DEVID_NONE:
673 dev_set_name(dev, "%s", pdev->name);
674 break;
675 case PLATFORM_DEVID_AUTO:
676 /*
677 * Automatically allocated device ID. We mark it as such so
678 * that we remember it must be freed, and we append a suffix
679 * to avoid namespace collision with explicit IDs.
680 */
681 ret = ida_alloc(&platform_devid_ida, GFP_KERNEL);
682 if (ret < 0)
683 return ret;
684 pdev->id = ret;
685 pdev->id_auto = true;
686 dev_set_name(dev, "%s.%d.auto", pdev->name, pdev->id);
687 break;
688 }
689
690 for (i = 0; i < pdev->num_resources; i++) {
691 struct resource *p, *r = &pdev->resource[i];
692
693 if (r->name == NULL)
694 r->name = dev_name(dev);
695
696 p = r->parent;
697 if (!p) {
698 if (resource_type(r) == IORESOURCE_MEM)
699 p = &iomem_resource;
700 else if (resource_type(r) == IORESOURCE_IO)
701 p = &ioport_resource;
702 }
703
704 if (p) {
705 ret = insert_resource(p, r);
706 if (ret) {
707 dev_err(dev, "failed to claim resource %d: %pR\n", i, r);
708 goto failed;
709 }
710 }
711 }
712
713 pr_debug("Registering platform device '%s'. Parent at %s\n", dev_name(dev),
714 dev_name(dev->parent));
715
716 ret = device_add(dev);
717 if (ret)
718 goto failed;
719
720 return 0;
721
722 failed:
723 if (pdev->id_auto) {
724 ida_free(&platform_devid_ida, pdev->id);
725 pdev->id = PLATFORM_DEVID_AUTO;
726 }
727
728 while (i--) {
729 struct resource *r = &pdev->resource[i];
730 if (r->parent)
731 release_resource(r);
732 }
733
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
886static int is_bound_to_driver(struct device *dev, void *driver)
887{
888 if (dev->driver == driver)
889 return 1;
890 return 0;
891}
892
893/**
894 * __platform_driver_probe - register driver for non-hotpluggable device
895 * @drv: platform driver structure
896 * @probe: the driver probe routine, probably from an __init section
897 * @module: module which will be the owner of the driver
898 *
899 * Use this instead of platform_driver_register() when you know the device
900 * is not hotpluggable and has already been registered, and you want to
901 * remove its run-once probe() infrastructure from memory after the driver
902 * has bound to the device.
903 *
904 * One typical use for this would be with drivers for controllers integrated
905 * into system-on-chip processors, where the controller devices have been
906 * configured as part of board setup.
907 *
908 * Note that this is incompatible with deferred probing.
909 *
910 * Returns zero if the driver registered and bound to a device, else returns
911 * a negative error code and with the driver not registered.
912 */
913int __init_or_module __platform_driver_probe(struct platform_driver *drv,
914 int (*probe)(struct platform_device *), struct module *module)
915{
916 int retval;
917
918 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
919 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
920 drv->driver.name, __func__);
921 return -EINVAL;
922 }
923
924 /*
925 * We have to run our probes synchronously because we check if
926 * we find any devices to bind to and exit with error if there
927 * are any.
928 */
929 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
930
931 /*
932 * Prevent driver from requesting probe deferral to avoid further
933 * futile probe attempts.
934 */
935 drv->prevent_deferred_probe = true;
936
937 /* make sure driver won't have bind/unbind attributes */
938 drv->driver.suppress_bind_attrs = true;
939
940 /* temporary section violation during probe() */
941 drv->probe = probe;
942 retval = __platform_driver_register(drv, module);
943 if (retval)
944 return retval;
945
946 /* Force all new probes of this driver to fail */
947 drv->probe = platform_probe_fail;
948
949 /* Walk all platform devices and see if any actually bound to this driver.
950 * If not, return an error as the device should have done so by now.
951 */
952 if (!bus_for_each_dev(&platform_bus_type, NULL, &drv->driver, is_bound_to_driver)) {
953 retval = -ENODEV;
954 platform_driver_unregister(drv);
955 }
956
957 return retval;
958}
959EXPORT_SYMBOL_GPL(__platform_driver_probe);
960
961/**
962 * __platform_create_bundle - register driver and create corresponding device
963 * @driver: platform driver structure
964 * @probe: the driver probe routine, probably from an __init section
965 * @res: set of resources that needs to be allocated for the device
966 * @n_res: number of resources
967 * @data: platform specific data for this platform device
968 * @size: size of platform specific data
969 * @module: module which will be the owner of the driver
970 *
971 * Use this in legacy-style modules that probe hardware directly and
972 * register a single platform device and corresponding platform driver.
973 *
974 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
975 */
976struct platform_device * __init_or_module __platform_create_bundle(
977 struct platform_driver *driver,
978 int (*probe)(struct platform_device *),
979 struct resource *res, unsigned int n_res,
980 const void *data, size_t size, struct module *module)
981{
982 struct platform_device *pdev;
983 int error;
984
985 pdev = platform_device_alloc(driver->driver.name, -1);
986 if (!pdev) {
987 error = -ENOMEM;
988 goto err_out;
989 }
990
991 error = platform_device_add_resources(pdev, res, n_res);
992 if (error)
993 goto err_pdev_put;
994
995 error = platform_device_add_data(pdev, data, size);
996 if (error)
997 goto err_pdev_put;
998
999 error = platform_device_add(pdev);
1000 if (error)
1001 goto err_pdev_put;
1002
1003 error = __platform_driver_probe(driver, probe, module);
1004 if (error)
1005 goto err_pdev_del;
1006
1007 return pdev;
1008
1009err_pdev_del:
1010 platform_device_del(pdev);
1011err_pdev_put:
1012 platform_device_put(pdev);
1013err_out:
1014 return ERR_PTR(error);
1015}
1016EXPORT_SYMBOL_GPL(__platform_create_bundle);
1017
1018/**
1019 * __platform_register_drivers - register an array of platform drivers
1020 * @drivers: an array of drivers to register
1021 * @count: the number of drivers to register
1022 * @owner: module owning the drivers
1023 *
1024 * Registers platform drivers specified by an array. On failure to register a
1025 * driver, all previously registered drivers will be unregistered. Callers of
1026 * this API should use platform_unregister_drivers() to unregister drivers in
1027 * the reverse order.
1028 *
1029 * Returns: 0 on success or a negative error code on failure.
1030 */
1031int __platform_register_drivers(struct platform_driver * const *drivers,
1032 unsigned int count, struct module *owner)
1033{
1034 unsigned int i;
1035 int err;
1036
1037 for (i = 0; i < count; i++) {
1038 pr_debug("registering platform driver %ps\n", drivers[i]);
1039
1040 err = __platform_driver_register(drivers[i], owner);
1041 if (err < 0) {
1042 pr_err("failed to register platform driver %ps: %d\n",
1043 drivers[i], err);
1044 goto error;
1045 }
1046 }
1047
1048 return 0;
1049
1050error:
1051 while (i--) {
1052 pr_debug("unregistering platform driver %ps\n", drivers[i]);
1053 platform_driver_unregister(drivers[i]);
1054 }
1055
1056 return err;
1057}
1058EXPORT_SYMBOL_GPL(__platform_register_drivers);
1059
1060/**
1061 * platform_unregister_drivers - unregister an array of platform drivers
1062 * @drivers: an array of drivers to unregister
1063 * @count: the number of drivers to unregister
1064 *
1065 * Unregisters platform drivers specified by an array. This is typically used
1066 * to complement an earlier call to platform_register_drivers(). Drivers are
1067 * unregistered in the reverse order in which they were registered.
1068 */
1069void platform_unregister_drivers(struct platform_driver * const *drivers,
1070 unsigned int count)
1071{
1072 while (count--) {
1073 pr_debug("unregistering platform driver %ps\n", drivers[count]);
1074 platform_driver_unregister(drivers[count]);
1075 }
1076}
1077EXPORT_SYMBOL_GPL(platform_unregister_drivers);
1078
1079static const struct platform_device_id *platform_match_id(
1080 const struct platform_device_id *id,
1081 struct platform_device *pdev)
1082{
1083 while (id->name[0]) {
1084 if (strcmp(pdev->name, id->name) == 0) {
1085 pdev->id_entry = id;
1086 return id;
1087 }
1088 id++;
1089 }
1090 return NULL;
1091}
1092
1093#ifdef CONFIG_PM_SLEEP
1094
1095static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1096{
1097 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1098 struct platform_device *pdev = to_platform_device(dev);
1099 int ret = 0;
1100
1101 if (dev->driver && pdrv->suspend)
1102 ret = pdrv->suspend(pdev, mesg);
1103
1104 return ret;
1105}
1106
1107static int platform_legacy_resume(struct device *dev)
1108{
1109 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1110 struct platform_device *pdev = to_platform_device(dev);
1111 int ret = 0;
1112
1113 if (dev->driver && pdrv->resume)
1114 ret = pdrv->resume(pdev);
1115
1116 return ret;
1117}
1118
1119#endif /* CONFIG_PM_SLEEP */
1120
1121#ifdef CONFIG_SUSPEND
1122
1123int platform_pm_suspend(struct device *dev)
1124{
1125 struct device_driver *drv = dev->driver;
1126 int ret = 0;
1127
1128 if (!drv)
1129 return 0;
1130
1131 if (drv->pm) {
1132 if (drv->pm->suspend)
1133 ret = drv->pm->suspend(dev);
1134 } else {
1135 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1136 }
1137
1138 return ret;
1139}
1140
1141int platform_pm_resume(struct device *dev)
1142{
1143 struct device_driver *drv = dev->driver;
1144 int ret = 0;
1145
1146 if (!drv)
1147 return 0;
1148
1149 if (drv->pm) {
1150 if (drv->pm->resume)
1151 ret = drv->pm->resume(dev);
1152 } else {
1153 ret = platform_legacy_resume(dev);
1154 }
1155
1156 return ret;
1157}
1158
1159#endif /* CONFIG_SUSPEND */
1160
1161#ifdef CONFIG_HIBERNATE_CALLBACKS
1162
1163int platform_pm_freeze(struct device *dev)
1164{
1165 struct device_driver *drv = dev->driver;
1166 int ret = 0;
1167
1168 if (!drv)
1169 return 0;
1170
1171 if (drv->pm) {
1172 if (drv->pm->freeze)
1173 ret = drv->pm->freeze(dev);
1174 } else {
1175 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1176 }
1177
1178 return ret;
1179}
1180
1181int platform_pm_thaw(struct device *dev)
1182{
1183 struct device_driver *drv = dev->driver;
1184 int ret = 0;
1185
1186 if (!drv)
1187 return 0;
1188
1189 if (drv->pm) {
1190 if (drv->pm->thaw)
1191 ret = drv->pm->thaw(dev);
1192 } else {
1193 ret = platform_legacy_resume(dev);
1194 }
1195
1196 return ret;
1197}
1198
1199int platform_pm_poweroff(struct device *dev)
1200{
1201 struct device_driver *drv = dev->driver;
1202 int ret = 0;
1203
1204 if (!drv)
1205 return 0;
1206
1207 if (drv->pm) {
1208 if (drv->pm->poweroff)
1209 ret = drv->pm->poweroff(dev);
1210 } else {
1211 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1212 }
1213
1214 return ret;
1215}
1216
1217int platform_pm_restore(struct device *dev)
1218{
1219 struct device_driver *drv = dev->driver;
1220 int ret = 0;
1221
1222 if (!drv)
1223 return 0;
1224
1225 if (drv->pm) {
1226 if (drv->pm->restore)
1227 ret = drv->pm->restore(dev);
1228 } else {
1229 ret = platform_legacy_resume(dev);
1230 }
1231
1232 return ret;
1233}
1234
1235#endif /* CONFIG_HIBERNATE_CALLBACKS */
1236
1237/* modalias support enables more hands-off userspace setup:
1238 * (a) environment variable lets new-style hotplug events work once system is
1239 * fully running: "modprobe $MODALIAS"
1240 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
1241 * mishandled before system is fully running: "modprobe $(cat modalias)"
1242 */
1243static ssize_t modalias_show(struct device *dev,
1244 struct device_attribute *attr, char *buf)
1245{
1246 struct platform_device *pdev = to_platform_device(dev);
1247 int len;
1248
1249 len = of_device_modalias(dev, buf, PAGE_SIZE);
1250 if (len != -ENODEV)
1251 return len;
1252
1253 len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
1254 if (len != -ENODEV)
1255 return len;
1256
1257 return sysfs_emit(buf, "platform:%s\n", pdev->name);
1258}
1259static DEVICE_ATTR_RO(modalias);
1260
1261static ssize_t numa_node_show(struct device *dev,
1262 struct device_attribute *attr, char *buf)
1263{
1264 return sysfs_emit(buf, "%d\n", dev_to_node(dev));
1265}
1266static DEVICE_ATTR_RO(numa_node);
1267
1268static ssize_t driver_override_show(struct device *dev,
1269 struct device_attribute *attr, char *buf)
1270{
1271 struct platform_device *pdev = to_platform_device(dev);
1272 ssize_t len;
1273
1274 device_lock(dev);
1275 len = sysfs_emit(buf, "%s\n", pdev->driver_override);
1276 device_unlock(dev);
1277
1278 return len;
1279}
1280
1281static ssize_t driver_override_store(struct device *dev,
1282 struct device_attribute *attr,
1283 const char *buf, size_t count)
1284{
1285 struct platform_device *pdev = to_platform_device(dev);
1286 int ret;
1287
1288 ret = driver_set_override(dev, &pdev->driver_override, buf, count);
1289 if (ret)
1290 return ret;
1291
1292 return count;
1293}
1294static DEVICE_ATTR_RW(driver_override);
1295
1296static struct attribute *platform_dev_attrs[] = {
1297 &dev_attr_modalias.attr,
1298 &dev_attr_numa_node.attr,
1299 &dev_attr_driver_override.attr,
1300 NULL,
1301};
1302
1303static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
1304 int n)
1305{
1306 struct device *dev = container_of(kobj, typeof(*dev), kobj);
1307
1308 if (a == &dev_attr_numa_node.attr &&
1309 dev_to_node(dev) == NUMA_NO_NODE)
1310 return 0;
1311
1312 return a->mode;
1313}
1314
1315static const struct attribute_group platform_dev_group = {
1316 .attrs = platform_dev_attrs,
1317 .is_visible = platform_dev_attrs_visible,
1318};
1319__ATTRIBUTE_GROUPS(platform_dev);
1320
1321
1322/**
1323 * platform_match - bind platform device to platform driver.
1324 * @dev: device.
1325 * @drv: driver.
1326 *
1327 * Platform device IDs are assumed to be encoded like this:
1328 * "<name><instance>", where <name> is a short description of the type of
1329 * device, like "pci" or "floppy", and <instance> is the enumerated
1330 * instance of the device, like '0' or '42'. Driver IDs are simply
1331 * "<name>". So, extract the <name> from the platform_device structure,
1332 * and compare it against the name of the driver. Return whether they match
1333 * or not.
1334 */
1335static int platform_match(struct device *dev, struct device_driver *drv)
1336{
1337 struct platform_device *pdev = to_platform_device(dev);
1338 struct platform_driver *pdrv = to_platform_driver(drv);
1339
1340 /* When driver_override is set, only bind to the matching driver */
1341 if (pdev->driver_override)
1342 return !strcmp(pdev->driver_override, drv->name);
1343
1344 /* Attempt an OF style match first */
1345 if (of_driver_match_device(dev, drv))
1346 return 1;
1347
1348 /* Then try ACPI style match */
1349 if (acpi_driver_match_device(dev, drv))
1350 return 1;
1351
1352 /* Then try to match against the id table */
1353 if (pdrv->id_table)
1354 return platform_match_id(pdrv->id_table, pdev) != NULL;
1355
1356 /* fall-back to driver name match */
1357 return (strcmp(pdev->name, drv->name) == 0);
1358}
1359
1360static int platform_uevent(const struct device *dev, struct kobj_uevent_env *env)
1361{
1362 const struct platform_device *pdev = to_platform_device(dev);
1363 int rc;
1364
1365 /* Some devices have extra OF data and an OF-style MODALIAS */
1366 rc = of_device_uevent_modalias(dev, env);
1367 if (rc != -ENODEV)
1368 return rc;
1369
1370 rc = acpi_device_uevent_modalias(dev, env);
1371 if (rc != -ENODEV)
1372 return rc;
1373
1374 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1375 pdev->name);
1376 return 0;
1377}
1378
1379static int platform_probe(struct device *_dev)
1380{
1381 struct platform_driver *drv = to_platform_driver(_dev->driver);
1382 struct platform_device *dev = to_platform_device(_dev);
1383 int ret;
1384
1385 /*
1386 * A driver registered using platform_driver_probe() cannot be bound
1387 * again later because the probe function usually lives in __init code
1388 * and so is gone. For these drivers .probe is set to
1389 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
1390 * clocks and PM domains for these to match the traditional behaviour.
1391 */
1392 if (unlikely(drv->probe == platform_probe_fail))
1393 return -ENXIO;
1394
1395 ret = of_clk_set_defaults(_dev->of_node, false);
1396 if (ret < 0)
1397 return ret;
1398
1399 ret = dev_pm_domain_attach(_dev, true);
1400 if (ret)
1401 goto out;
1402
1403 if (drv->probe) {
1404 ret = drv->probe(dev);
1405 if (ret)
1406 dev_pm_domain_detach(_dev, true);
1407 }
1408
1409out:
1410 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
1411 dev_warn(_dev, "probe deferral not supported\n");
1412 ret = -ENXIO;
1413 }
1414
1415 return ret;
1416}
1417
1418static void platform_remove(struct device *_dev)
1419{
1420 struct platform_driver *drv = to_platform_driver(_dev->driver);
1421 struct platform_device *dev = to_platform_device(_dev);
1422
1423 if (drv->remove_new) {
1424 drv->remove_new(dev);
1425 } else if (drv->remove) {
1426 int ret = drv->remove(dev);
1427
1428 if (ret)
1429 dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n");
1430 }
1431 dev_pm_domain_detach(_dev, true);
1432}
1433
1434static void platform_shutdown(struct device *_dev)
1435{
1436 struct platform_device *dev = to_platform_device(_dev);
1437 struct platform_driver *drv;
1438
1439 if (!_dev->driver)
1440 return;
1441
1442 drv = to_platform_driver(_dev->driver);
1443 if (drv->shutdown)
1444 drv->shutdown(dev);
1445}
1446
1447static int platform_dma_configure(struct device *dev)
1448{
1449 struct platform_driver *drv = to_platform_driver(dev->driver);
1450 struct fwnode_handle *fwnode = dev_fwnode(dev);
1451 enum dev_dma_attr attr;
1452 int ret = 0;
1453
1454 if (is_of_node(fwnode)) {
1455 ret = of_dma_configure(dev, to_of_node(fwnode), true);
1456 } else if (is_acpi_device_node(fwnode)) {
1457 attr = acpi_get_dma_attr(to_acpi_device_node(fwnode));
1458 ret = acpi_dma_configure(dev, attr);
1459 }
1460 if (ret || drv->driver_managed_dma)
1461 return ret;
1462
1463 ret = iommu_device_use_default_domain(dev);
1464 if (ret)
1465 arch_teardown_dma_ops(dev);
1466
1467 return ret;
1468}
1469
1470static void platform_dma_cleanup(struct device *dev)
1471{
1472 struct platform_driver *drv = to_platform_driver(dev->driver);
1473
1474 if (!drv->driver_managed_dma)
1475 iommu_device_unuse_default_domain(dev);
1476}
1477
1478static const struct dev_pm_ops platform_dev_pm_ops = {
1479 SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend, pm_generic_runtime_resume, NULL)
1480 USE_PLATFORM_PM_SLEEP_OPS
1481};
1482
1483struct bus_type platform_bus_type = {
1484 .name = "platform",
1485 .dev_groups = platform_dev_groups,
1486 .match = platform_match,
1487 .uevent = platform_uevent,
1488 .probe = platform_probe,
1489 .remove = platform_remove,
1490 .shutdown = platform_shutdown,
1491 .dma_configure = platform_dma_configure,
1492 .dma_cleanup = platform_dma_cleanup,
1493 .pm = &platform_dev_pm_ops,
1494};
1495EXPORT_SYMBOL_GPL(platform_bus_type);
1496
1497static inline int __platform_match(struct device *dev, const void *drv)
1498{
1499 return platform_match(dev, (struct device_driver *)drv);
1500}
1501
1502/**
1503 * platform_find_device_by_driver - Find a platform device with a given
1504 * driver.
1505 * @start: The device to start the search from.
1506 * @drv: The device driver to look for.
1507 */
1508struct device *platform_find_device_by_driver(struct device *start,
1509 const struct device_driver *drv)
1510{
1511 return bus_find_device(&platform_bus_type, start, drv,
1512 __platform_match);
1513}
1514EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1515
1516void __weak __init early_platform_cleanup(void) { }
1517
1518int __init platform_bus_init(void)
1519{
1520 int error;
1521
1522 early_platform_cleanup();
1523
1524 error = device_register(&platform_bus);
1525 if (error) {
1526 put_device(&platform_bus);
1527 return error;
1528 }
1529 error = bus_register(&platform_bus_type);
1530 if (error)
1531 device_unregister(&platform_bus);
1532
1533 return error;
1534}
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 irqd_set_trigger_type(irq_get_irq_data(r->start),
113 r->flags & IORESOURCE_BITS);
114
115 return r ? r->start : -ENXIO;
116#endif
117}
118EXPORT_SYMBOL_GPL(platform_get_irq);
119
120/**
121 * platform_irq_count - Count the number of IRQs a platform device uses
122 * @dev: platform device
123 *
124 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
125 */
126int platform_irq_count(struct platform_device *dev)
127{
128 int ret, nr = 0;
129
130 while ((ret = platform_get_irq(dev, nr)) >= 0)
131 nr++;
132
133 if (ret == -EPROBE_DEFER)
134 return ret;
135
136 return nr;
137}
138EXPORT_SYMBOL_GPL(platform_irq_count);
139
140/**
141 * platform_get_resource_byname - get a resource for a device by name
142 * @dev: platform device
143 * @type: resource type
144 * @name: resource name
145 */
146struct resource *platform_get_resource_byname(struct platform_device *dev,
147 unsigned int type,
148 const char *name)
149{
150 int i;
151
152 for (i = 0; i < dev->num_resources; i++) {
153 struct resource *r = &dev->resource[i];
154
155 if (unlikely(!r->name))
156 continue;
157
158 if (type == resource_type(r) && !strcmp(r->name, name))
159 return r;
160 }
161 return NULL;
162}
163EXPORT_SYMBOL_GPL(platform_get_resource_byname);
164
165/**
166 * platform_get_irq_byname - get an IRQ for a device by name
167 * @dev: platform device
168 * @name: IRQ name
169 */
170int platform_get_irq_byname(struct platform_device *dev, const char *name)
171{
172 struct resource *r;
173
174 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
175 int ret;
176
177 ret = of_irq_get_byname(dev->dev.of_node, name);
178 if (ret >= 0 || ret == -EPROBE_DEFER)
179 return ret;
180 }
181
182 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
183 return r ? r->start : -ENXIO;
184}
185EXPORT_SYMBOL_GPL(platform_get_irq_byname);
186
187/**
188 * platform_add_devices - add a numbers of platform devices
189 * @devs: array of platform devices to add
190 * @num: number of platform devices in array
191 */
192int platform_add_devices(struct platform_device **devs, int num)
193{
194 int i, ret = 0;
195
196 for (i = 0; i < num; i++) {
197 ret = platform_device_register(devs[i]);
198 if (ret) {
199 while (--i >= 0)
200 platform_device_unregister(devs[i]);
201 break;
202 }
203 }
204
205 return ret;
206}
207EXPORT_SYMBOL_GPL(platform_add_devices);
208
209struct platform_object {
210 struct platform_device pdev;
211 char name[];
212};
213
214/**
215 * platform_device_put - destroy a platform device
216 * @pdev: platform device to free
217 *
218 * Free all memory associated with a platform device. This function must
219 * _only_ be externally called in error cases. All other usage is a bug.
220 */
221void platform_device_put(struct platform_device *pdev)
222{
223 if (pdev)
224 put_device(&pdev->dev);
225}
226EXPORT_SYMBOL_GPL(platform_device_put);
227
228static void platform_device_release(struct device *dev)
229{
230 struct platform_object *pa = container_of(dev, struct platform_object,
231 pdev.dev);
232
233 of_device_node_put(&pa->pdev.dev);
234 kfree(pa->pdev.dev.platform_data);
235 kfree(pa->pdev.mfd_cell);
236 kfree(pa->pdev.resource);
237 kfree(pa->pdev.driver_override);
238 kfree(pa);
239}
240
241/**
242 * platform_device_alloc - create a platform device
243 * @name: base name of the device we're adding
244 * @id: instance id
245 *
246 * Create a platform device object which can have other objects attached
247 * to it, and which will have attached objects freed when it is released.
248 */
249struct platform_device *platform_device_alloc(const char *name, int id)
250{
251 struct platform_object *pa;
252
253 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
254 if (pa) {
255 strcpy(pa->name, name);
256 pa->pdev.name = pa->name;
257 pa->pdev.id = id;
258 device_initialize(&pa->pdev.dev);
259 pa->pdev.dev.release = platform_device_release;
260 arch_setup_pdev_archdata(&pa->pdev);
261 }
262
263 return pa ? &pa->pdev : NULL;
264}
265EXPORT_SYMBOL_GPL(platform_device_alloc);
266
267/**
268 * platform_device_add_resources - add resources to a platform device
269 * @pdev: platform device allocated by platform_device_alloc to add resources to
270 * @res: set of resources that needs to be allocated for the device
271 * @num: number of resources
272 *
273 * Add a copy of the resources to the platform device. The memory
274 * associated with the resources will be freed when the platform device is
275 * released.
276 */
277int platform_device_add_resources(struct platform_device *pdev,
278 const struct resource *res, unsigned int num)
279{
280 struct resource *r = NULL;
281
282 if (res) {
283 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
284 if (!r)
285 return -ENOMEM;
286 }
287
288 kfree(pdev->resource);
289 pdev->resource = r;
290 pdev->num_resources = num;
291 return 0;
292}
293EXPORT_SYMBOL_GPL(platform_device_add_resources);
294
295/**
296 * platform_device_add_data - add platform-specific data to a platform device
297 * @pdev: platform device allocated by platform_device_alloc to add resources to
298 * @data: platform specific data for this platform device
299 * @size: size of platform specific data
300 *
301 * Add a copy of platform specific data to the platform device's
302 * platform_data pointer. The memory associated with the platform data
303 * will be freed when the platform device is released.
304 */
305int platform_device_add_data(struct platform_device *pdev, const void *data,
306 size_t size)
307{
308 void *d = NULL;
309
310 if (data) {
311 d = kmemdup(data, size, GFP_KERNEL);
312 if (!d)
313 return -ENOMEM;
314 }
315
316 kfree(pdev->dev.platform_data);
317 pdev->dev.platform_data = d;
318 return 0;
319}
320EXPORT_SYMBOL_GPL(platform_device_add_data);
321
322/**
323 * platform_device_add_properties - add built-in properties to a platform device
324 * @pdev: platform device to add properties to
325 * @pset: properties to add
326 *
327 * The function will take deep copy of the properties in @pset and attach
328 * the copy to the platform device. The memory associated with properties
329 * will be freed when the platform device is released.
330 */
331int platform_device_add_properties(struct platform_device *pdev,
332 const struct property_set *pset)
333{
334 return device_add_property_set(&pdev->dev, pset);
335}
336EXPORT_SYMBOL_GPL(platform_device_add_properties);
337
338/**
339 * platform_device_add - add a platform device to device hierarchy
340 * @pdev: platform device we're adding
341 *
342 * This is part 2 of platform_device_register(), though may be called
343 * separately _iff_ pdev was allocated by platform_device_alloc().
344 */
345int platform_device_add(struct platform_device *pdev)
346{
347 int i, ret;
348
349 if (!pdev)
350 return -EINVAL;
351
352 if (!pdev->dev.parent)
353 pdev->dev.parent = &platform_bus;
354
355 pdev->dev.bus = &platform_bus_type;
356
357 switch (pdev->id) {
358 default:
359 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
360 break;
361 case PLATFORM_DEVID_NONE:
362 dev_set_name(&pdev->dev, "%s", pdev->name);
363 break;
364 case PLATFORM_DEVID_AUTO:
365 /*
366 * Automatically allocated device ID. We mark it as such so
367 * that we remember it must be freed, and we append a suffix
368 * to avoid namespace collision with explicit IDs.
369 */
370 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
371 if (ret < 0)
372 goto err_out;
373 pdev->id = ret;
374 pdev->id_auto = true;
375 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
376 break;
377 }
378
379 for (i = 0; i < pdev->num_resources; i++) {
380 struct resource *p, *r = &pdev->resource[i];
381
382 if (r->name == NULL)
383 r->name = dev_name(&pdev->dev);
384
385 p = r->parent;
386 if (!p) {
387 if (resource_type(r) == IORESOURCE_MEM)
388 p = &iomem_resource;
389 else if (resource_type(r) == IORESOURCE_IO)
390 p = &ioport_resource;
391 }
392
393 if (p && insert_resource(p, r)) {
394 dev_err(&pdev->dev, "failed to claim resource %d\n", i);
395 ret = -EBUSY;
396 goto failed;
397 }
398 }
399
400 pr_debug("Registering platform device '%s'. Parent at %s\n",
401 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
402
403 ret = device_add(&pdev->dev);
404 if (ret == 0)
405 return ret;
406
407 failed:
408 if (pdev->id_auto) {
409 ida_simple_remove(&platform_devid_ida, pdev->id);
410 pdev->id = PLATFORM_DEVID_AUTO;
411 }
412
413 while (--i >= 0) {
414 struct resource *r = &pdev->resource[i];
415 if (r->parent)
416 release_resource(r);
417 }
418
419 err_out:
420 return ret;
421}
422EXPORT_SYMBOL_GPL(platform_device_add);
423
424/**
425 * platform_device_del - remove a platform-level device
426 * @pdev: platform device we're removing
427 *
428 * Note that this function will also release all memory- and port-based
429 * resources owned by the device (@dev->resource). This function must
430 * _only_ be externally called in error cases. All other usage is a bug.
431 */
432void platform_device_del(struct platform_device *pdev)
433{
434 int i;
435
436 if (pdev) {
437 device_del(&pdev->dev);
438
439 if (pdev->id_auto) {
440 ida_simple_remove(&platform_devid_ida, pdev->id);
441 pdev->id = PLATFORM_DEVID_AUTO;
442 }
443
444 for (i = 0; i < pdev->num_resources; i++) {
445 struct resource *r = &pdev->resource[i];
446 if (r->parent)
447 release_resource(r);
448 }
449
450 device_remove_property_set(&pdev->dev);
451 }
452}
453EXPORT_SYMBOL_GPL(platform_device_del);
454
455/**
456 * platform_device_register - add a platform-level device
457 * @pdev: platform device we're adding
458 */
459int platform_device_register(struct platform_device *pdev)
460{
461 device_initialize(&pdev->dev);
462 arch_setup_pdev_archdata(pdev);
463 return platform_device_add(pdev);
464}
465EXPORT_SYMBOL_GPL(platform_device_register);
466
467/**
468 * platform_device_unregister - unregister a platform-level device
469 * @pdev: platform device we're unregistering
470 *
471 * Unregistration is done in 2 steps. First we release all resources
472 * and remove it from the subsystem, then we drop reference count by
473 * calling platform_device_put().
474 */
475void platform_device_unregister(struct platform_device *pdev)
476{
477 platform_device_del(pdev);
478 platform_device_put(pdev);
479}
480EXPORT_SYMBOL_GPL(platform_device_unregister);
481
482/**
483 * platform_device_register_full - add a platform-level device with
484 * resources and platform-specific data
485 *
486 * @pdevinfo: data used to create device
487 *
488 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
489 */
490struct platform_device *platform_device_register_full(
491 const struct platform_device_info *pdevinfo)
492{
493 int ret = -ENOMEM;
494 struct platform_device *pdev;
495
496 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
497 if (!pdev)
498 goto err_alloc;
499
500 pdev->dev.parent = pdevinfo->parent;
501 pdev->dev.fwnode = pdevinfo->fwnode;
502
503 if (pdevinfo->dma_mask) {
504 /*
505 * This memory isn't freed when the device is put,
506 * I don't have a nice idea for that though. Conceptually
507 * dma_mask in struct device should not be a pointer.
508 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
509 */
510 pdev->dev.dma_mask =
511 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
512 if (!pdev->dev.dma_mask)
513 goto err;
514
515 *pdev->dev.dma_mask = pdevinfo->dma_mask;
516 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
517 }
518
519 ret = platform_device_add_resources(pdev,
520 pdevinfo->res, pdevinfo->num_res);
521 if (ret)
522 goto err;
523
524 ret = platform_device_add_data(pdev,
525 pdevinfo->data, pdevinfo->size_data);
526 if (ret)
527 goto err;
528
529 if (pdevinfo->pset) {
530 ret = platform_device_add_properties(pdev, pdevinfo->pset);
531 if (ret)
532 goto err;
533 }
534
535 ret = platform_device_add(pdev);
536 if (ret) {
537err:
538 ACPI_COMPANION_SET(&pdev->dev, NULL);
539 kfree(pdev->dev.dma_mask);
540
541err_alloc:
542 platform_device_put(pdev);
543 return ERR_PTR(ret);
544 }
545
546 return pdev;
547}
548EXPORT_SYMBOL_GPL(platform_device_register_full);
549
550static int platform_drv_probe(struct device *_dev)
551{
552 struct platform_driver *drv = to_platform_driver(_dev->driver);
553 struct platform_device *dev = to_platform_device(_dev);
554 int ret;
555
556 ret = of_clk_set_defaults(_dev->of_node, false);
557 if (ret < 0)
558 return ret;
559
560 ret = dev_pm_domain_attach(_dev, true);
561 if (ret != -EPROBE_DEFER) {
562 if (drv->probe) {
563 ret = drv->probe(dev);
564 if (ret)
565 dev_pm_domain_detach(_dev, true);
566 } else {
567 /* don't fail if just dev_pm_domain_attach failed */
568 ret = 0;
569 }
570 }
571
572 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
573 dev_warn(_dev, "probe deferral not supported\n");
574 ret = -ENXIO;
575 }
576
577 return ret;
578}
579
580static int platform_drv_probe_fail(struct device *_dev)
581{
582 return -ENXIO;
583}
584
585static int platform_drv_remove(struct device *_dev)
586{
587 struct platform_driver *drv = to_platform_driver(_dev->driver);
588 struct platform_device *dev = to_platform_device(_dev);
589 int ret = 0;
590
591 if (drv->remove)
592 ret = drv->remove(dev);
593 dev_pm_domain_detach(_dev, true);
594
595 return ret;
596}
597
598static void platform_drv_shutdown(struct device *_dev)
599{
600 struct platform_driver *drv = to_platform_driver(_dev->driver);
601 struct platform_device *dev = to_platform_device(_dev);
602
603 if (drv->shutdown)
604 drv->shutdown(dev);
605}
606
607/**
608 * __platform_driver_register - register a driver for platform-level devices
609 * @drv: platform driver structure
610 * @owner: owning module/driver
611 */
612int __platform_driver_register(struct platform_driver *drv,
613 struct module *owner)
614{
615 drv->driver.owner = owner;
616 drv->driver.bus = &platform_bus_type;
617 drv->driver.probe = platform_drv_probe;
618 drv->driver.remove = platform_drv_remove;
619 drv->driver.shutdown = platform_drv_shutdown;
620
621 return driver_register(&drv->driver);
622}
623EXPORT_SYMBOL_GPL(__platform_driver_register);
624
625/**
626 * platform_driver_unregister - unregister a driver for platform-level devices
627 * @drv: platform driver structure
628 */
629void platform_driver_unregister(struct platform_driver *drv)
630{
631 driver_unregister(&drv->driver);
632}
633EXPORT_SYMBOL_GPL(platform_driver_unregister);
634
635/**
636 * __platform_driver_probe - register driver for non-hotpluggable device
637 * @drv: platform driver structure
638 * @probe: the driver probe routine, probably from an __init section
639 * @module: module which will be the owner of the driver
640 *
641 * Use this instead of platform_driver_register() when you know the device
642 * is not hotpluggable and has already been registered, and you want to
643 * remove its run-once probe() infrastructure from memory after the driver
644 * has bound to the device.
645 *
646 * One typical use for this would be with drivers for controllers integrated
647 * into system-on-chip processors, where the controller devices have been
648 * configured as part of board setup.
649 *
650 * Note that this is incompatible with deferred probing.
651 *
652 * Returns zero if the driver registered and bound to a device, else returns
653 * a negative error code and with the driver not registered.
654 */
655int __init_or_module __platform_driver_probe(struct platform_driver *drv,
656 int (*probe)(struct platform_device *), struct module *module)
657{
658 int retval, code;
659
660 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
661 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
662 drv->driver.name, __func__);
663 return -EINVAL;
664 }
665
666 /*
667 * We have to run our probes synchronously because we check if
668 * we find any devices to bind to and exit with error if there
669 * are any.
670 */
671 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
672
673 /*
674 * Prevent driver from requesting probe deferral to avoid further
675 * futile probe attempts.
676 */
677 drv->prevent_deferred_probe = true;
678
679 /* make sure driver won't have bind/unbind attributes */
680 drv->driver.suppress_bind_attrs = true;
681
682 /* temporary section violation during probe() */
683 drv->probe = probe;
684 retval = code = __platform_driver_register(drv, module);
685
686 /*
687 * Fixup that section violation, being paranoid about code scanning
688 * the list of drivers in order to probe new devices. Check to see
689 * if the probe was successful, and make sure any forced probes of
690 * new devices fail.
691 */
692 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
693 drv->probe = NULL;
694 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
695 retval = -ENODEV;
696 drv->driver.probe = platform_drv_probe_fail;
697 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
698
699 if (code != retval)
700 platform_driver_unregister(drv);
701 return retval;
702}
703EXPORT_SYMBOL_GPL(__platform_driver_probe);
704
705/**
706 * __platform_create_bundle - register driver and create corresponding device
707 * @driver: platform driver structure
708 * @probe: the driver probe routine, probably from an __init section
709 * @res: set of resources that needs to be allocated for the device
710 * @n_res: number of resources
711 * @data: platform specific data for this platform device
712 * @size: size of platform specific data
713 * @module: module which will be the owner of the driver
714 *
715 * Use this in legacy-style modules that probe hardware directly and
716 * register a single platform device and corresponding platform driver.
717 *
718 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
719 */
720struct platform_device * __init_or_module __platform_create_bundle(
721 struct platform_driver *driver,
722 int (*probe)(struct platform_device *),
723 struct resource *res, unsigned int n_res,
724 const void *data, size_t size, struct module *module)
725{
726 struct platform_device *pdev;
727 int error;
728
729 pdev = platform_device_alloc(driver->driver.name, -1);
730 if (!pdev) {
731 error = -ENOMEM;
732 goto err_out;
733 }
734
735 error = platform_device_add_resources(pdev, res, n_res);
736 if (error)
737 goto err_pdev_put;
738
739 error = platform_device_add_data(pdev, data, size);
740 if (error)
741 goto err_pdev_put;
742
743 error = platform_device_add(pdev);
744 if (error)
745 goto err_pdev_put;
746
747 error = __platform_driver_probe(driver, probe, module);
748 if (error)
749 goto err_pdev_del;
750
751 return pdev;
752
753err_pdev_del:
754 platform_device_del(pdev);
755err_pdev_put:
756 platform_device_put(pdev);
757err_out:
758 return ERR_PTR(error);
759}
760EXPORT_SYMBOL_GPL(__platform_create_bundle);
761
762/**
763 * __platform_register_drivers - register an array of platform drivers
764 * @drivers: an array of drivers to register
765 * @count: the number of drivers to register
766 * @owner: module owning the drivers
767 *
768 * Registers platform drivers specified by an array. On failure to register a
769 * driver, all previously registered drivers will be unregistered. Callers of
770 * this API should use platform_unregister_drivers() to unregister drivers in
771 * the reverse order.
772 *
773 * Returns: 0 on success or a negative error code on failure.
774 */
775int __platform_register_drivers(struct platform_driver * const *drivers,
776 unsigned int count, struct module *owner)
777{
778 unsigned int i;
779 int err;
780
781 for (i = 0; i < count; i++) {
782 pr_debug("registering platform driver %ps\n", drivers[i]);
783
784 err = __platform_driver_register(drivers[i], owner);
785 if (err < 0) {
786 pr_err("failed to register platform driver %ps: %d\n",
787 drivers[i], err);
788 goto error;
789 }
790 }
791
792 return 0;
793
794error:
795 while (i--) {
796 pr_debug("unregistering platform driver %ps\n", drivers[i]);
797 platform_driver_unregister(drivers[i]);
798 }
799
800 return err;
801}
802EXPORT_SYMBOL_GPL(__platform_register_drivers);
803
804/**
805 * platform_unregister_drivers - unregister an array of platform drivers
806 * @drivers: an array of drivers to unregister
807 * @count: the number of drivers to unregister
808 *
809 * Unegisters platform drivers specified by an array. This is typically used
810 * to complement an earlier call to platform_register_drivers(). Drivers are
811 * unregistered in the reverse order in which they were registered.
812 */
813void platform_unregister_drivers(struct platform_driver * const *drivers,
814 unsigned int count)
815{
816 while (count--) {
817 pr_debug("unregistering platform driver %ps\n", drivers[count]);
818 platform_driver_unregister(drivers[count]);
819 }
820}
821EXPORT_SYMBOL_GPL(platform_unregister_drivers);
822
823/* modalias support enables more hands-off userspace setup:
824 * (a) environment variable lets new-style hotplug events work once system is
825 * fully running: "modprobe $MODALIAS"
826 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
827 * mishandled before system is fully running: "modprobe $(cat modalias)"
828 */
829static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
830 char *buf)
831{
832 struct platform_device *pdev = to_platform_device(dev);
833 int len;
834
835 len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
836 if (len != -ENODEV)
837 return len;
838
839 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
840 if (len != -ENODEV)
841 return len;
842
843 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
844
845 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
846}
847static DEVICE_ATTR_RO(modalias);
848
849static ssize_t driver_override_store(struct device *dev,
850 struct device_attribute *attr,
851 const char *buf, size_t count)
852{
853 struct platform_device *pdev = to_platform_device(dev);
854 char *driver_override, *old = pdev->driver_override, *cp;
855
856 if (count > PATH_MAX)
857 return -EINVAL;
858
859 driver_override = kstrndup(buf, count, GFP_KERNEL);
860 if (!driver_override)
861 return -ENOMEM;
862
863 cp = strchr(driver_override, '\n');
864 if (cp)
865 *cp = '\0';
866
867 if (strlen(driver_override)) {
868 pdev->driver_override = driver_override;
869 } else {
870 kfree(driver_override);
871 pdev->driver_override = NULL;
872 }
873
874 kfree(old);
875
876 return count;
877}
878
879static ssize_t driver_override_show(struct device *dev,
880 struct device_attribute *attr, char *buf)
881{
882 struct platform_device *pdev = to_platform_device(dev);
883
884 return sprintf(buf, "%s\n", pdev->driver_override);
885}
886static DEVICE_ATTR_RW(driver_override);
887
888
889static struct attribute *platform_dev_attrs[] = {
890 &dev_attr_modalias.attr,
891 &dev_attr_driver_override.attr,
892 NULL,
893};
894ATTRIBUTE_GROUPS(platform_dev);
895
896static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
897{
898 struct platform_device *pdev = to_platform_device(dev);
899 int rc;
900
901 /* Some devices have extra OF data and an OF-style MODALIAS */
902 rc = of_device_uevent_modalias(dev, env);
903 if (rc != -ENODEV)
904 return rc;
905
906 rc = acpi_device_uevent_modalias(dev, env);
907 if (rc != -ENODEV)
908 return rc;
909
910 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
911 pdev->name);
912 return 0;
913}
914
915static const struct platform_device_id *platform_match_id(
916 const struct platform_device_id *id,
917 struct platform_device *pdev)
918{
919 while (id->name[0]) {
920 if (strcmp(pdev->name, id->name) == 0) {
921 pdev->id_entry = id;
922 return id;
923 }
924 id++;
925 }
926 return NULL;
927}
928
929/**
930 * platform_match - bind platform device to platform driver.
931 * @dev: device.
932 * @drv: driver.
933 *
934 * Platform device IDs are assumed to be encoded like this:
935 * "<name><instance>", where <name> is a short description of the type of
936 * device, like "pci" or "floppy", and <instance> is the enumerated
937 * instance of the device, like '0' or '42'. Driver IDs are simply
938 * "<name>". So, extract the <name> from the platform_device structure,
939 * and compare it against the name of the driver. Return whether they match
940 * or not.
941 */
942static int platform_match(struct device *dev, struct device_driver *drv)
943{
944 struct platform_device *pdev = to_platform_device(dev);
945 struct platform_driver *pdrv = to_platform_driver(drv);
946
947 /* When driver_override is set, only bind to the matching driver */
948 if (pdev->driver_override)
949 return !strcmp(pdev->driver_override, drv->name);
950
951 /* Attempt an OF style match first */
952 if (of_driver_match_device(dev, drv))
953 return 1;
954
955 /* Then try ACPI style match */
956 if (acpi_driver_match_device(dev, drv))
957 return 1;
958
959 /* Then try to match against the id table */
960 if (pdrv->id_table)
961 return platform_match_id(pdrv->id_table, pdev) != NULL;
962
963 /* fall-back to driver name match */
964 return (strcmp(pdev->name, drv->name) == 0);
965}
966
967#ifdef CONFIG_PM_SLEEP
968
969static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
970{
971 struct platform_driver *pdrv = to_platform_driver(dev->driver);
972 struct platform_device *pdev = to_platform_device(dev);
973 int ret = 0;
974
975 if (dev->driver && pdrv->suspend)
976 ret = pdrv->suspend(pdev, mesg);
977
978 return ret;
979}
980
981static int platform_legacy_resume(struct device *dev)
982{
983 struct platform_driver *pdrv = to_platform_driver(dev->driver);
984 struct platform_device *pdev = to_platform_device(dev);
985 int ret = 0;
986
987 if (dev->driver && pdrv->resume)
988 ret = pdrv->resume(pdev);
989
990 return ret;
991}
992
993#endif /* CONFIG_PM_SLEEP */
994
995#ifdef CONFIG_SUSPEND
996
997int platform_pm_suspend(struct device *dev)
998{
999 struct device_driver *drv = dev->driver;
1000 int ret = 0;
1001
1002 if (!drv)
1003 return 0;
1004
1005 if (drv->pm) {
1006 if (drv->pm->suspend)
1007 ret = drv->pm->suspend(dev);
1008 } else {
1009 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1010 }
1011
1012 return ret;
1013}
1014
1015int platform_pm_resume(struct device *dev)
1016{
1017 struct device_driver *drv = dev->driver;
1018 int ret = 0;
1019
1020 if (!drv)
1021 return 0;
1022
1023 if (drv->pm) {
1024 if (drv->pm->resume)
1025 ret = drv->pm->resume(dev);
1026 } else {
1027 ret = platform_legacy_resume(dev);
1028 }
1029
1030 return ret;
1031}
1032
1033#endif /* CONFIG_SUSPEND */
1034
1035#ifdef CONFIG_HIBERNATE_CALLBACKS
1036
1037int platform_pm_freeze(struct device *dev)
1038{
1039 struct device_driver *drv = dev->driver;
1040 int ret = 0;
1041
1042 if (!drv)
1043 return 0;
1044
1045 if (drv->pm) {
1046 if (drv->pm->freeze)
1047 ret = drv->pm->freeze(dev);
1048 } else {
1049 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1050 }
1051
1052 return ret;
1053}
1054
1055int platform_pm_thaw(struct device *dev)
1056{
1057 struct device_driver *drv = dev->driver;
1058 int ret = 0;
1059
1060 if (!drv)
1061 return 0;
1062
1063 if (drv->pm) {
1064 if (drv->pm->thaw)
1065 ret = drv->pm->thaw(dev);
1066 } else {
1067 ret = platform_legacy_resume(dev);
1068 }
1069
1070 return ret;
1071}
1072
1073int platform_pm_poweroff(struct device *dev)
1074{
1075 struct device_driver *drv = dev->driver;
1076 int ret = 0;
1077
1078 if (!drv)
1079 return 0;
1080
1081 if (drv->pm) {
1082 if (drv->pm->poweroff)
1083 ret = drv->pm->poweroff(dev);
1084 } else {
1085 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1086 }
1087
1088 return ret;
1089}
1090
1091int platform_pm_restore(struct device *dev)
1092{
1093 struct device_driver *drv = dev->driver;
1094 int ret = 0;
1095
1096 if (!drv)
1097 return 0;
1098
1099 if (drv->pm) {
1100 if (drv->pm->restore)
1101 ret = drv->pm->restore(dev);
1102 } else {
1103 ret = platform_legacy_resume(dev);
1104 }
1105
1106 return ret;
1107}
1108
1109#endif /* CONFIG_HIBERNATE_CALLBACKS */
1110
1111static const struct dev_pm_ops platform_dev_pm_ops = {
1112 .runtime_suspend = pm_generic_runtime_suspend,
1113 .runtime_resume = pm_generic_runtime_resume,
1114 USE_PLATFORM_PM_SLEEP_OPS
1115};
1116
1117struct bus_type platform_bus_type = {
1118 .name = "platform",
1119 .dev_groups = platform_dev_groups,
1120 .match = platform_match,
1121 .uevent = platform_uevent,
1122 .pm = &platform_dev_pm_ops,
1123};
1124EXPORT_SYMBOL_GPL(platform_bus_type);
1125
1126int __init platform_bus_init(void)
1127{
1128 int error;
1129
1130 early_platform_cleanup();
1131
1132 error = device_register(&platform_bus);
1133 if (error)
1134 return error;
1135 error = bus_register(&platform_bus_type);
1136 if (error)
1137 device_unregister(&platform_bus);
1138 of_platform_register_reconfig_notifier();
1139 return error;
1140}
1141
1142#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1143u64 dma_get_required_mask(struct device *dev)
1144{
1145 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
1146 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
1147 u64 mask;
1148
1149 if (!high_totalram) {
1150 /* convert to mask just covering totalram */
1151 low_totalram = (1 << (fls(low_totalram) - 1));
1152 low_totalram += low_totalram - 1;
1153 mask = low_totalram;
1154 } else {
1155 high_totalram = (1 << (fls(high_totalram) - 1));
1156 high_totalram += high_totalram - 1;
1157 mask = (((u64)high_totalram) << 32) + 0xffffffff;
1158 }
1159 return mask;
1160}
1161EXPORT_SYMBOL_GPL(dma_get_required_mask);
1162#endif
1163
1164static __initdata LIST_HEAD(early_platform_driver_list);
1165static __initdata LIST_HEAD(early_platform_device_list);
1166
1167/**
1168 * early_platform_driver_register - register early platform driver
1169 * @epdrv: early_platform driver structure
1170 * @buf: string passed from early_param()
1171 *
1172 * Helper function for early_platform_init() / early_platform_init_buffer()
1173 */
1174int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1175 char *buf)
1176{
1177 char *tmp;
1178 int n;
1179
1180 /* Simply add the driver to the end of the global list.
1181 * Drivers will by default be put on the list in compiled-in order.
1182 */
1183 if (!epdrv->list.next) {
1184 INIT_LIST_HEAD(&epdrv->list);
1185 list_add_tail(&epdrv->list, &early_platform_driver_list);
1186 }
1187
1188 /* If the user has specified device then make sure the driver
1189 * gets prioritized. The driver of the last device specified on
1190 * command line will be put first on the list.
1191 */
1192 n = strlen(epdrv->pdrv->driver.name);
1193 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1194 list_move(&epdrv->list, &early_platform_driver_list);
1195
1196 /* Allow passing parameters after device name */
1197 if (buf[n] == '\0' || buf[n] == ',')
1198 epdrv->requested_id = -1;
1199 else {
1200 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1201 &tmp, 10);
1202
1203 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1204 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1205 n = 0;
1206 } else
1207 n += strcspn(&buf[n + 1], ",") + 1;
1208 }
1209
1210 if (buf[n] == ',')
1211 n++;
1212
1213 if (epdrv->bufsize) {
1214 memcpy(epdrv->buffer, &buf[n],
1215 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1216 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1217 }
1218 }
1219
1220 return 0;
1221}
1222
1223/**
1224 * early_platform_add_devices - adds a number of early platform devices
1225 * @devs: array of early platform devices to add
1226 * @num: number of early platform devices in array
1227 *
1228 * Used by early architecture code to register early platform devices and
1229 * their platform data.
1230 */
1231void __init early_platform_add_devices(struct platform_device **devs, int num)
1232{
1233 struct device *dev;
1234 int i;
1235
1236 /* simply add the devices to list */
1237 for (i = 0; i < num; i++) {
1238 dev = &devs[i]->dev;
1239
1240 if (!dev->devres_head.next) {
1241 pm_runtime_early_init(dev);
1242 INIT_LIST_HEAD(&dev->devres_head);
1243 list_add_tail(&dev->devres_head,
1244 &early_platform_device_list);
1245 }
1246 }
1247}
1248
1249/**
1250 * early_platform_driver_register_all - register early platform drivers
1251 * @class_str: string to identify early platform driver class
1252 *
1253 * Used by architecture code to register all early platform drivers
1254 * for a certain class. If omitted then only early platform drivers
1255 * with matching kernel command line class parameters will be registered.
1256 */
1257void __init early_platform_driver_register_all(char *class_str)
1258{
1259 /* The "class_str" parameter may or may not be present on the kernel
1260 * command line. If it is present then there may be more than one
1261 * matching parameter.
1262 *
1263 * Since we register our early platform drivers using early_param()
1264 * we need to make sure that they also get registered in the case
1265 * when the parameter is missing from the kernel command line.
1266 *
1267 * We use parse_early_options() to make sure the early_param() gets
1268 * called at least once. The early_param() may be called more than
1269 * once since the name of the preferred device may be specified on
1270 * the kernel command line. early_platform_driver_register() handles
1271 * this case for us.
1272 */
1273 parse_early_options(class_str);
1274}
1275
1276/**
1277 * early_platform_match - find early platform device matching driver
1278 * @epdrv: early platform driver structure
1279 * @id: id to match against
1280 */
1281static struct platform_device * __init
1282early_platform_match(struct early_platform_driver *epdrv, int id)
1283{
1284 struct platform_device *pd;
1285
1286 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1287 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1288 if (pd->id == id)
1289 return pd;
1290
1291 return NULL;
1292}
1293
1294/**
1295 * early_platform_left - check if early platform driver has matching devices
1296 * @epdrv: early platform driver structure
1297 * @id: return true if id or above exists
1298 */
1299static int __init early_platform_left(struct early_platform_driver *epdrv,
1300 int id)
1301{
1302 struct platform_device *pd;
1303
1304 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1305 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1306 if (pd->id >= id)
1307 return 1;
1308
1309 return 0;
1310}
1311
1312/**
1313 * early_platform_driver_probe_id - probe drivers matching class_str and id
1314 * @class_str: string to identify early platform driver class
1315 * @id: id to match against
1316 * @nr_probe: number of platform devices to successfully probe before exiting
1317 */
1318static int __init early_platform_driver_probe_id(char *class_str,
1319 int id,
1320 int nr_probe)
1321{
1322 struct early_platform_driver *epdrv;
1323 struct platform_device *match;
1324 int match_id;
1325 int n = 0;
1326 int left = 0;
1327
1328 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1329 /* only use drivers matching our class_str */
1330 if (strcmp(class_str, epdrv->class_str))
1331 continue;
1332
1333 if (id == -2) {
1334 match_id = epdrv->requested_id;
1335 left = 1;
1336
1337 } else {
1338 match_id = id;
1339 left += early_platform_left(epdrv, id);
1340
1341 /* skip requested id */
1342 switch (epdrv->requested_id) {
1343 case EARLY_PLATFORM_ID_ERROR:
1344 case EARLY_PLATFORM_ID_UNSET:
1345 break;
1346 default:
1347 if (epdrv->requested_id == id)
1348 match_id = EARLY_PLATFORM_ID_UNSET;
1349 }
1350 }
1351
1352 switch (match_id) {
1353 case EARLY_PLATFORM_ID_ERROR:
1354 pr_warn("%s: unable to parse %s parameter\n",
1355 class_str, epdrv->pdrv->driver.name);
1356 /* fall-through */
1357 case EARLY_PLATFORM_ID_UNSET:
1358 match = NULL;
1359 break;
1360 default:
1361 match = early_platform_match(epdrv, match_id);
1362 }
1363
1364 if (match) {
1365 /*
1366 * Set up a sensible init_name to enable
1367 * dev_name() and others to be used before the
1368 * rest of the driver core is initialized.
1369 */
1370 if (!match->dev.init_name && slab_is_available()) {
1371 if (match->id != -1)
1372 match->dev.init_name =
1373 kasprintf(GFP_KERNEL, "%s.%d",
1374 match->name,
1375 match->id);
1376 else
1377 match->dev.init_name =
1378 kasprintf(GFP_KERNEL, "%s",
1379 match->name);
1380
1381 if (!match->dev.init_name)
1382 return -ENOMEM;
1383 }
1384
1385 if (epdrv->pdrv->probe(match))
1386 pr_warn("%s: unable to probe %s early.\n",
1387 class_str, match->name);
1388 else
1389 n++;
1390 }
1391
1392 if (n >= nr_probe)
1393 break;
1394 }
1395
1396 if (left)
1397 return n;
1398 else
1399 return -ENODEV;
1400}
1401
1402/**
1403 * early_platform_driver_probe - probe a class of registered drivers
1404 * @class_str: string to identify early platform driver class
1405 * @nr_probe: number of platform devices to successfully probe before exiting
1406 * @user_only: only probe user specified early platform devices
1407 *
1408 * Used by architecture code to probe registered early platform drivers
1409 * within a certain class. For probe to happen a registered early platform
1410 * device matching a registered early platform driver is needed.
1411 */
1412int __init early_platform_driver_probe(char *class_str,
1413 int nr_probe,
1414 int user_only)
1415{
1416 int k, n, i;
1417
1418 n = 0;
1419 for (i = -2; n < nr_probe; i++) {
1420 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1421
1422 if (k < 0)
1423 break;
1424
1425 n += k;
1426
1427 if (user_only)
1428 break;
1429 }
1430
1431 return n;
1432}
1433
1434/**
1435 * early_platform_cleanup - clean up early platform code
1436 */
1437void __init early_platform_cleanup(void)
1438{
1439 struct platform_device *pd, *pd2;
1440
1441 /* clean up the devres list used to chain devices */
1442 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1443 dev.devres_head) {
1444 list_del(&pd->dev.devres_head);
1445 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1446 }
1447}
1448