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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
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/dma-mapping.h>
19#include <linux/memblock.h>
20#include <linux/err.h>
21#include <linux/slab.h>
22#include <linux/pm_runtime.h>
23#include <linux/pm_domain.h>
24#include <linux/idr.h>
25#include <linux/acpi.h>
26#include <linux/clk/clk-conf.h>
27#include <linux/limits.h>
28#include <linux/property.h>
29#include <linux/kmemleak.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 * platform_get_resource - get a resource for a device
44 * @dev: platform device
45 * @type: resource type
46 * @num: resource index
47 */
48struct resource *platform_get_resource(struct platform_device *dev,
49 unsigned int type, unsigned int num)
50{
51 int i;
52
53 for (i = 0; i < dev->num_resources; i++) {
54 struct resource *r = &dev->resource[i];
55
56 if (type == resource_type(r) && num-- == 0)
57 return r;
58 }
59 return NULL;
60}
61EXPORT_SYMBOL_GPL(platform_get_resource);
62
63/**
64 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
65 * device
66 *
67 * @pdev: platform device to use both for memory resource lookup as well as
68 * resource management
69 * @index: resource index
70 */
71#ifdef CONFIG_HAS_IOMEM
72void __iomem *devm_platform_ioremap_resource(struct platform_device *pdev,
73 unsigned int index)
74{
75 struct resource *res;
76
77 res = platform_get_resource(pdev, IORESOURCE_MEM, index);
78 return devm_ioremap_resource(&pdev->dev, res);
79}
80EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource);
81#endif /* CONFIG_HAS_IOMEM */
82
83static int __platform_get_irq(struct platform_device *dev, unsigned int num)
84{
85#ifdef CONFIG_SPARC
86 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
87 if (!dev || num >= dev->archdata.num_irqs)
88 return -ENXIO;
89 return dev->archdata.irqs[num];
90#else
91 struct resource *r;
92 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
93 int ret;
94
95 ret = of_irq_get(dev->dev.of_node, num);
96 if (ret > 0 || ret == -EPROBE_DEFER)
97 return ret;
98 }
99
100 r = platform_get_resource(dev, IORESOURCE_IRQ, num);
101 if (has_acpi_companion(&dev->dev)) {
102 if (r && r->flags & IORESOURCE_DISABLED) {
103 int ret;
104
105 ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
106 if (ret)
107 return ret;
108 }
109 }
110
111 /*
112 * The resources may pass trigger flags to the irqs that need
113 * to be set up. It so happens that the trigger flags for
114 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
115 * settings.
116 */
117 if (r && r->flags & IORESOURCE_BITS) {
118 struct irq_data *irqd;
119
120 irqd = irq_get_irq_data(r->start);
121 if (!irqd)
122 return -ENXIO;
123 irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);
124 }
125
126 if (r)
127 return r->start;
128
129 /*
130 * For the index 0 interrupt, allow falling back to GpioInt
131 * resources. While a device could have both Interrupt and GpioInt
132 * resources, making this fallback ambiguous, in many common cases
133 * the device will only expose one IRQ, and this fallback
134 * allows a common code path across either kind of resource.
135 */
136 if (num == 0 && has_acpi_companion(&dev->dev)) {
137 int ret = acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev->dev), num);
138
139 /* Our callers expect -ENXIO for missing IRQs. */
140 if (ret >= 0 || ret == -EPROBE_DEFER)
141 return ret;
142 }
143
144 return -ENXIO;
145#endif
146}
147
148/**
149 * platform_get_irq - get an IRQ for a device
150 * @dev: platform device
151 * @num: IRQ number index
152 *
153 * Gets an IRQ for a platform device and prints an error message if finding the
154 * IRQ fails. Device drivers should check the return value for errors so as to
155 * not pass a negative integer value to the request_irq() APIs.
156 *
157 * Example:
158 * int irq = platform_get_irq(pdev, 0);
159 * if (irq < 0)
160 * return irq;
161 *
162 * Return: IRQ number on success, negative error number on failure.
163 */
164int platform_get_irq(struct platform_device *dev, unsigned int num)
165{
166 int ret;
167
168 ret = __platform_get_irq(dev, num);
169 if (ret < 0 && ret != -EPROBE_DEFER)
170 dev_err(&dev->dev, "IRQ index %u not found\n", num);
171
172 return ret;
173}
174EXPORT_SYMBOL_GPL(platform_get_irq);
175
176/**
177 * platform_get_irq_optional - get an optional IRQ for a device
178 * @dev: platform device
179 * @num: IRQ number index
180 *
181 * Gets an IRQ for a platform device. Device drivers should check the return
182 * value for errors so as to not pass a negative integer value to the
183 * request_irq() APIs. This is the same as platform_get_irq(), except that it
184 * does not print an error message if an IRQ can not be obtained.
185 *
186 * Example:
187 * int irq = platform_get_irq_optional(pdev, 0);
188 * if (irq < 0)
189 * return irq;
190 *
191 * Return: IRQ number on success, negative error number on failure.
192 */
193int platform_get_irq_optional(struct platform_device *dev, unsigned int num)
194{
195 return __platform_get_irq(dev, num);
196}
197EXPORT_SYMBOL_GPL(platform_get_irq_optional);
198
199/**
200 * platform_irq_count - Count the number of IRQs a platform device uses
201 * @dev: platform device
202 *
203 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
204 */
205int platform_irq_count(struct platform_device *dev)
206{
207 int ret, nr = 0;
208
209 while ((ret = __platform_get_irq(dev, nr)) >= 0)
210 nr++;
211
212 if (ret == -EPROBE_DEFER)
213 return ret;
214
215 return nr;
216}
217EXPORT_SYMBOL_GPL(platform_irq_count);
218
219/**
220 * platform_get_resource_byname - get a resource for a device by name
221 * @dev: platform device
222 * @type: resource type
223 * @name: resource name
224 */
225struct resource *platform_get_resource_byname(struct platform_device *dev,
226 unsigned int type,
227 const char *name)
228{
229 int i;
230
231 for (i = 0; i < dev->num_resources; i++) {
232 struct resource *r = &dev->resource[i];
233
234 if (unlikely(!r->name))
235 continue;
236
237 if (type == resource_type(r) && !strcmp(r->name, name))
238 return r;
239 }
240 return NULL;
241}
242EXPORT_SYMBOL_GPL(platform_get_resource_byname);
243
244static int __platform_get_irq_byname(struct platform_device *dev,
245 const char *name)
246{
247 struct resource *r;
248
249 if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
250 int ret;
251
252 ret = of_irq_get_byname(dev->dev.of_node, name);
253 if (ret > 0 || ret == -EPROBE_DEFER)
254 return ret;
255 }
256
257 r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name);
258 if (r)
259 return r->start;
260
261 return -ENXIO;
262}
263
264/**
265 * platform_get_irq_byname - get an IRQ for a device by name
266 * @dev: platform device
267 * @name: IRQ name
268 *
269 * Get an IRQ like platform_get_irq(), but then by name rather then by index.
270 *
271 * Return: IRQ number on success, negative error number on failure.
272 */
273int platform_get_irq_byname(struct platform_device *dev, const char *name)
274{
275 int ret;
276
277 ret = __platform_get_irq_byname(dev, name);
278 if (ret < 0 && ret != -EPROBE_DEFER)
279 dev_err(&dev->dev, "IRQ %s not found\n", name);
280
281 return ret;
282}
283EXPORT_SYMBOL_GPL(platform_get_irq_byname);
284
285/**
286 * platform_get_irq_byname_optional - get an optional IRQ for a device by name
287 * @dev: platform device
288 * @name: IRQ name
289 *
290 * Get an optional IRQ by name like platform_get_irq_byname(). Except that it
291 * does not print an error message if an IRQ can not be obtained.
292 *
293 * Return: IRQ number on success, negative error number on failure.
294 */
295int platform_get_irq_byname_optional(struct platform_device *dev,
296 const char *name)
297{
298 return __platform_get_irq_byname(dev, name);
299}
300EXPORT_SYMBOL_GPL(platform_get_irq_byname_optional);
301
302/**
303 * platform_add_devices - add a numbers of platform devices
304 * @devs: array of platform devices to add
305 * @num: number of platform devices in array
306 */
307int platform_add_devices(struct platform_device **devs, int num)
308{
309 int i, ret = 0;
310
311 for (i = 0; i < num; i++) {
312 ret = platform_device_register(devs[i]);
313 if (ret) {
314 while (--i >= 0)
315 platform_device_unregister(devs[i]);
316 break;
317 }
318 }
319
320 return ret;
321}
322EXPORT_SYMBOL_GPL(platform_add_devices);
323
324struct platform_object {
325 struct platform_device pdev;
326 char name[];
327};
328
329/*
330 * Set up default DMA mask for platform devices if the they weren't
331 * previously set by the architecture / DT.
332 */
333static void setup_pdev_dma_masks(struct platform_device *pdev)
334{
335 if (!pdev->dev.coherent_dma_mask)
336 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
337 if (!pdev->dma_mask)
338 pdev->dma_mask = DMA_BIT_MASK(32);
339 if (!pdev->dev.dma_mask)
340 pdev->dev.dma_mask = &pdev->dma_mask;
341};
342
343/**
344 * platform_device_put - destroy a platform device
345 * @pdev: platform device to free
346 *
347 * Free all memory associated with a platform device. This function must
348 * _only_ be externally called in error cases. All other usage is a bug.
349 */
350void platform_device_put(struct platform_device *pdev)
351{
352 if (!IS_ERR_OR_NULL(pdev))
353 put_device(&pdev->dev);
354}
355EXPORT_SYMBOL_GPL(platform_device_put);
356
357static void platform_device_release(struct device *dev)
358{
359 struct platform_object *pa = container_of(dev, struct platform_object,
360 pdev.dev);
361
362 of_device_node_put(&pa->pdev.dev);
363 kfree(pa->pdev.dev.platform_data);
364 kfree(pa->pdev.mfd_cell);
365 kfree(pa->pdev.resource);
366 kfree(pa->pdev.driver_override);
367 kfree(pa);
368}
369
370/**
371 * platform_device_alloc - create a platform device
372 * @name: base name of the device we're adding
373 * @id: instance id
374 *
375 * Create a platform device object which can have other objects attached
376 * to it, and which will have attached objects freed when it is released.
377 */
378struct platform_device *platform_device_alloc(const char *name, int id)
379{
380 struct platform_object *pa;
381
382 pa = kzalloc(sizeof(*pa) + strlen(name) + 1, GFP_KERNEL);
383 if (pa) {
384 strcpy(pa->name, name);
385 pa->pdev.name = pa->name;
386 pa->pdev.id = id;
387 device_initialize(&pa->pdev.dev);
388 pa->pdev.dev.release = platform_device_release;
389 setup_pdev_dma_masks(&pa->pdev);
390 }
391
392 return pa ? &pa->pdev : NULL;
393}
394EXPORT_SYMBOL_GPL(platform_device_alloc);
395
396/**
397 * platform_device_add_resources - add resources to a platform device
398 * @pdev: platform device allocated by platform_device_alloc to add resources to
399 * @res: set of resources that needs to be allocated for the device
400 * @num: number of resources
401 *
402 * Add a copy of the resources to the platform device. The memory
403 * associated with the resources will be freed when the platform device is
404 * released.
405 */
406int platform_device_add_resources(struct platform_device *pdev,
407 const struct resource *res, unsigned int num)
408{
409 struct resource *r = NULL;
410
411 if (res) {
412 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
413 if (!r)
414 return -ENOMEM;
415 }
416
417 kfree(pdev->resource);
418 pdev->resource = r;
419 pdev->num_resources = num;
420 return 0;
421}
422EXPORT_SYMBOL_GPL(platform_device_add_resources);
423
424/**
425 * platform_device_add_data - add platform-specific data to a platform device
426 * @pdev: platform device allocated by platform_device_alloc to add resources to
427 * @data: platform specific data for this platform device
428 * @size: size of platform specific data
429 *
430 * Add a copy of platform specific data to the platform device's
431 * platform_data pointer. The memory associated with the platform data
432 * will be freed when the platform device is released.
433 */
434int platform_device_add_data(struct platform_device *pdev, const void *data,
435 size_t size)
436{
437 void *d = NULL;
438
439 if (data) {
440 d = kmemdup(data, size, GFP_KERNEL);
441 if (!d)
442 return -ENOMEM;
443 }
444
445 kfree(pdev->dev.platform_data);
446 pdev->dev.platform_data = d;
447 return 0;
448}
449EXPORT_SYMBOL_GPL(platform_device_add_data);
450
451/**
452 * platform_device_add_properties - add built-in properties to a platform device
453 * @pdev: platform device to add properties to
454 * @properties: null terminated array of properties to add
455 *
456 * The function will take deep copy of @properties and attach the copy to the
457 * platform device. The memory associated with properties will be freed when the
458 * platform device is released.
459 */
460int platform_device_add_properties(struct platform_device *pdev,
461 const struct property_entry *properties)
462{
463 return device_add_properties(&pdev->dev, properties);
464}
465EXPORT_SYMBOL_GPL(platform_device_add_properties);
466
467/**
468 * platform_device_add - add a platform device to device hierarchy
469 * @pdev: platform device we're adding
470 *
471 * This is part 2 of platform_device_register(), though may be called
472 * separately _iff_ pdev was allocated by platform_device_alloc().
473 */
474int platform_device_add(struct platform_device *pdev)
475{
476 int i, ret;
477
478 if (!pdev)
479 return -EINVAL;
480
481 if (!pdev->dev.parent)
482 pdev->dev.parent = &platform_bus;
483
484 pdev->dev.bus = &platform_bus_type;
485
486 switch (pdev->id) {
487 default:
488 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
489 break;
490 case PLATFORM_DEVID_NONE:
491 dev_set_name(&pdev->dev, "%s", pdev->name);
492 break;
493 case PLATFORM_DEVID_AUTO:
494 /*
495 * Automatically allocated device ID. We mark it as such so
496 * that we remember it must be freed, and we append a suffix
497 * to avoid namespace collision with explicit IDs.
498 */
499 ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
500 if (ret < 0)
501 goto err_out;
502 pdev->id = ret;
503 pdev->id_auto = true;
504 dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
505 break;
506 }
507
508 for (i = 0; i < pdev->num_resources; i++) {
509 struct resource *p, *r = &pdev->resource[i];
510
511 if (r->name == NULL)
512 r->name = dev_name(&pdev->dev);
513
514 p = r->parent;
515 if (!p) {
516 if (resource_type(r) == IORESOURCE_MEM)
517 p = &iomem_resource;
518 else if (resource_type(r) == IORESOURCE_IO)
519 p = &ioport_resource;
520 }
521
522 if (p) {
523 ret = insert_resource(p, r);
524 if (ret) {
525 dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r);
526 goto failed;
527 }
528 }
529 }
530
531 pr_debug("Registering platform device '%s'. Parent at %s\n",
532 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
533
534 ret = device_add(&pdev->dev);
535 if (ret == 0)
536 return ret;
537
538 failed:
539 if (pdev->id_auto) {
540 ida_simple_remove(&platform_devid_ida, pdev->id);
541 pdev->id = PLATFORM_DEVID_AUTO;
542 }
543
544 while (--i >= 0) {
545 struct resource *r = &pdev->resource[i];
546 if (r->parent)
547 release_resource(r);
548 }
549
550 err_out:
551 return ret;
552}
553EXPORT_SYMBOL_GPL(platform_device_add);
554
555/**
556 * platform_device_del - remove a platform-level device
557 * @pdev: platform device we're removing
558 *
559 * Note that this function will also release all memory- and port-based
560 * resources owned by the device (@dev->resource). This function must
561 * _only_ be externally called in error cases. All other usage is a bug.
562 */
563void platform_device_del(struct platform_device *pdev)
564{
565 int i;
566
567 if (!IS_ERR_OR_NULL(pdev)) {
568 device_del(&pdev->dev);
569
570 if (pdev->id_auto) {
571 ida_simple_remove(&platform_devid_ida, pdev->id);
572 pdev->id = PLATFORM_DEVID_AUTO;
573 }
574
575 for (i = 0; i < pdev->num_resources; i++) {
576 struct resource *r = &pdev->resource[i];
577 if (r->parent)
578 release_resource(r);
579 }
580 }
581}
582EXPORT_SYMBOL_GPL(platform_device_del);
583
584/**
585 * platform_device_register - add a platform-level device
586 * @pdev: platform device we're adding
587 */
588int platform_device_register(struct platform_device *pdev)
589{
590 device_initialize(&pdev->dev);
591 setup_pdev_dma_masks(pdev);
592 return platform_device_add(pdev);
593}
594EXPORT_SYMBOL_GPL(platform_device_register);
595
596/**
597 * platform_device_unregister - unregister a platform-level device
598 * @pdev: platform device we're unregistering
599 *
600 * Unregistration is done in 2 steps. First we release all resources
601 * and remove it from the subsystem, then we drop reference count by
602 * calling platform_device_put().
603 */
604void platform_device_unregister(struct platform_device *pdev)
605{
606 platform_device_del(pdev);
607 platform_device_put(pdev);
608}
609EXPORT_SYMBOL_GPL(platform_device_unregister);
610
611/**
612 * platform_device_register_full - add a platform-level device with
613 * resources and platform-specific data
614 *
615 * @pdevinfo: data used to create device
616 *
617 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
618 */
619struct platform_device *platform_device_register_full(
620 const struct platform_device_info *pdevinfo)
621{
622 int ret = -ENOMEM;
623 struct platform_device *pdev;
624
625 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
626 if (!pdev)
627 return ERR_PTR(-ENOMEM);
628
629 pdev->dev.parent = pdevinfo->parent;
630 pdev->dev.fwnode = pdevinfo->fwnode;
631 pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode));
632 pdev->dev.of_node_reused = pdevinfo->of_node_reused;
633
634 if (pdevinfo->dma_mask) {
635 /*
636 * This memory isn't freed when the device is put,
637 * I don't have a nice idea for that though. Conceptually
638 * dma_mask in struct device should not be a pointer.
639 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
640 */
641 pdev->dev.dma_mask =
642 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
643 if (!pdev->dev.dma_mask)
644 goto err;
645
646 kmemleak_ignore(pdev->dev.dma_mask);
647
648 *pdev->dev.dma_mask = pdevinfo->dma_mask;
649 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
650 }
651
652 ret = platform_device_add_resources(pdev,
653 pdevinfo->res, pdevinfo->num_res);
654 if (ret)
655 goto err;
656
657 ret = platform_device_add_data(pdev,
658 pdevinfo->data, pdevinfo->size_data);
659 if (ret)
660 goto err;
661
662 if (pdevinfo->properties) {
663 ret = platform_device_add_properties(pdev,
664 pdevinfo->properties);
665 if (ret)
666 goto err;
667 }
668
669 ret = platform_device_add(pdev);
670 if (ret) {
671err:
672 ACPI_COMPANION_SET(&pdev->dev, NULL);
673 kfree(pdev->dev.dma_mask);
674 platform_device_put(pdev);
675 return ERR_PTR(ret);
676 }
677
678 return pdev;
679}
680EXPORT_SYMBOL_GPL(platform_device_register_full);
681
682static int platform_drv_probe(struct device *_dev)
683{
684 struct platform_driver *drv = to_platform_driver(_dev->driver);
685 struct platform_device *dev = to_platform_device(_dev);
686 int ret;
687
688 ret = of_clk_set_defaults(_dev->of_node, false);
689 if (ret < 0)
690 return ret;
691
692 ret = dev_pm_domain_attach(_dev, true);
693 if (ret)
694 goto out;
695
696 if (drv->probe) {
697 ret = drv->probe(dev);
698 if (ret)
699 dev_pm_domain_detach(_dev, true);
700 }
701
702out:
703 if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
704 dev_warn(_dev, "probe deferral not supported\n");
705 ret = -ENXIO;
706 }
707
708 return ret;
709}
710
711static int platform_drv_probe_fail(struct device *_dev)
712{
713 return -ENXIO;
714}
715
716static int platform_drv_remove(struct device *_dev)
717{
718 struct platform_driver *drv = to_platform_driver(_dev->driver);
719 struct platform_device *dev = to_platform_device(_dev);
720 int ret = 0;
721
722 if (drv->remove)
723 ret = drv->remove(dev);
724 dev_pm_domain_detach(_dev, true);
725
726 return ret;
727}
728
729static void platform_drv_shutdown(struct device *_dev)
730{
731 struct platform_driver *drv = to_platform_driver(_dev->driver);
732 struct platform_device *dev = to_platform_device(_dev);
733
734 if (drv->shutdown)
735 drv->shutdown(dev);
736}
737
738/**
739 * __platform_driver_register - register a driver for platform-level devices
740 * @drv: platform driver structure
741 * @owner: owning module/driver
742 */
743int __platform_driver_register(struct platform_driver *drv,
744 struct module *owner)
745{
746 drv->driver.owner = owner;
747 drv->driver.bus = &platform_bus_type;
748 drv->driver.probe = platform_drv_probe;
749 drv->driver.remove = platform_drv_remove;
750 drv->driver.shutdown = platform_drv_shutdown;
751
752 return driver_register(&drv->driver);
753}
754EXPORT_SYMBOL_GPL(__platform_driver_register);
755
756/**
757 * platform_driver_unregister - unregister a driver for platform-level devices
758 * @drv: platform driver structure
759 */
760void platform_driver_unregister(struct platform_driver *drv)
761{
762 driver_unregister(&drv->driver);
763}
764EXPORT_SYMBOL_GPL(platform_driver_unregister);
765
766/**
767 * __platform_driver_probe - register driver for non-hotpluggable device
768 * @drv: platform driver structure
769 * @probe: the driver probe routine, probably from an __init section
770 * @module: module which will be the owner of the driver
771 *
772 * Use this instead of platform_driver_register() when you know the device
773 * is not hotpluggable and has already been registered, and you want to
774 * remove its run-once probe() infrastructure from memory after the driver
775 * has bound to the device.
776 *
777 * One typical use for this would be with drivers for controllers integrated
778 * into system-on-chip processors, where the controller devices have been
779 * configured as part of board setup.
780 *
781 * Note that this is incompatible with deferred probing.
782 *
783 * Returns zero if the driver registered and bound to a device, else returns
784 * a negative error code and with the driver not registered.
785 */
786int __init_or_module __platform_driver_probe(struct platform_driver *drv,
787 int (*probe)(struct platform_device *), struct module *module)
788{
789 int retval, code;
790
791 if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) {
792 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
793 drv->driver.name, __func__);
794 return -EINVAL;
795 }
796
797 /*
798 * We have to run our probes synchronously because we check if
799 * we find any devices to bind to and exit with error if there
800 * are any.
801 */
802 drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS;
803
804 /*
805 * Prevent driver from requesting probe deferral to avoid further
806 * futile probe attempts.
807 */
808 drv->prevent_deferred_probe = true;
809
810 /* make sure driver won't have bind/unbind attributes */
811 drv->driver.suppress_bind_attrs = true;
812
813 /* temporary section violation during probe() */
814 drv->probe = probe;
815 retval = code = __platform_driver_register(drv, module);
816
817 /*
818 * Fixup that section violation, being paranoid about code scanning
819 * the list of drivers in order to probe new devices. Check to see
820 * if the probe was successful, and make sure any forced probes of
821 * new devices fail.
822 */
823 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
824 drv->probe = NULL;
825 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
826 retval = -ENODEV;
827 drv->driver.probe = platform_drv_probe_fail;
828 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
829
830 if (code != retval)
831 platform_driver_unregister(drv);
832 return retval;
833}
834EXPORT_SYMBOL_GPL(__platform_driver_probe);
835
836/**
837 * __platform_create_bundle - register driver and create corresponding device
838 * @driver: platform driver structure
839 * @probe: the driver probe routine, probably from an __init section
840 * @res: set of resources that needs to be allocated for the device
841 * @n_res: number of resources
842 * @data: platform specific data for this platform device
843 * @size: size of platform specific data
844 * @module: module which will be the owner of the driver
845 *
846 * Use this in legacy-style modules that probe hardware directly and
847 * register a single platform device and corresponding platform driver.
848 *
849 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
850 */
851struct platform_device * __init_or_module __platform_create_bundle(
852 struct platform_driver *driver,
853 int (*probe)(struct platform_device *),
854 struct resource *res, unsigned int n_res,
855 const void *data, size_t size, struct module *module)
856{
857 struct platform_device *pdev;
858 int error;
859
860 pdev = platform_device_alloc(driver->driver.name, -1);
861 if (!pdev) {
862 error = -ENOMEM;
863 goto err_out;
864 }
865
866 error = platform_device_add_resources(pdev, res, n_res);
867 if (error)
868 goto err_pdev_put;
869
870 error = platform_device_add_data(pdev, data, size);
871 if (error)
872 goto err_pdev_put;
873
874 error = platform_device_add(pdev);
875 if (error)
876 goto err_pdev_put;
877
878 error = __platform_driver_probe(driver, probe, module);
879 if (error)
880 goto err_pdev_del;
881
882 return pdev;
883
884err_pdev_del:
885 platform_device_del(pdev);
886err_pdev_put:
887 platform_device_put(pdev);
888err_out:
889 return ERR_PTR(error);
890}
891EXPORT_SYMBOL_GPL(__platform_create_bundle);
892
893/**
894 * __platform_register_drivers - register an array of platform drivers
895 * @drivers: an array of drivers to register
896 * @count: the number of drivers to register
897 * @owner: module owning the drivers
898 *
899 * Registers platform drivers specified by an array. On failure to register a
900 * driver, all previously registered drivers will be unregistered. Callers of
901 * this API should use platform_unregister_drivers() to unregister drivers in
902 * the reverse order.
903 *
904 * Returns: 0 on success or a negative error code on failure.
905 */
906int __platform_register_drivers(struct platform_driver * const *drivers,
907 unsigned int count, struct module *owner)
908{
909 unsigned int i;
910 int err;
911
912 for (i = 0; i < count; i++) {
913 pr_debug("registering platform driver %ps\n", drivers[i]);
914
915 err = __platform_driver_register(drivers[i], owner);
916 if (err < 0) {
917 pr_err("failed to register platform driver %ps: %d\n",
918 drivers[i], err);
919 goto error;
920 }
921 }
922
923 return 0;
924
925error:
926 while (i--) {
927 pr_debug("unregistering platform driver %ps\n", drivers[i]);
928 platform_driver_unregister(drivers[i]);
929 }
930
931 return err;
932}
933EXPORT_SYMBOL_GPL(__platform_register_drivers);
934
935/**
936 * platform_unregister_drivers - unregister an array of platform drivers
937 * @drivers: an array of drivers to unregister
938 * @count: the number of drivers to unregister
939 *
940 * Unegisters platform drivers specified by an array. This is typically used
941 * to complement an earlier call to platform_register_drivers(). Drivers are
942 * unregistered in the reverse order in which they were registered.
943 */
944void platform_unregister_drivers(struct platform_driver * const *drivers,
945 unsigned int count)
946{
947 while (count--) {
948 pr_debug("unregistering platform driver %ps\n", drivers[count]);
949 platform_driver_unregister(drivers[count]);
950 }
951}
952EXPORT_SYMBOL_GPL(platform_unregister_drivers);
953
954/* modalias support enables more hands-off userspace setup:
955 * (a) environment variable lets new-style hotplug events work once system is
956 * fully running: "modprobe $MODALIAS"
957 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
958 * mishandled before system is fully running: "modprobe $(cat modalias)"
959 */
960static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
961 char *buf)
962{
963 struct platform_device *pdev = to_platform_device(dev);
964 int len;
965
966 len = of_device_modalias(dev, buf, PAGE_SIZE);
967 if (len != -ENODEV)
968 return len;
969
970 len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
971 if (len != -ENODEV)
972 return len;
973
974 len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
975
976 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
977}
978static DEVICE_ATTR_RO(modalias);
979
980static ssize_t driver_override_store(struct device *dev,
981 struct device_attribute *attr,
982 const char *buf, size_t count)
983{
984 struct platform_device *pdev = to_platform_device(dev);
985 char *driver_override, *old, *cp;
986
987 /* We need to keep extra room for a newline */
988 if (count >= (PAGE_SIZE - 1))
989 return -EINVAL;
990
991 driver_override = kstrndup(buf, count, GFP_KERNEL);
992 if (!driver_override)
993 return -ENOMEM;
994
995 cp = strchr(driver_override, '\n');
996 if (cp)
997 *cp = '\0';
998
999 device_lock(dev);
1000 old = pdev->driver_override;
1001 if (strlen(driver_override)) {
1002 pdev->driver_override = driver_override;
1003 } else {
1004 kfree(driver_override);
1005 pdev->driver_override = NULL;
1006 }
1007 device_unlock(dev);
1008
1009 kfree(old);
1010
1011 return count;
1012}
1013
1014static ssize_t driver_override_show(struct device *dev,
1015 struct device_attribute *attr, char *buf)
1016{
1017 struct platform_device *pdev = to_platform_device(dev);
1018 ssize_t len;
1019
1020 device_lock(dev);
1021 len = sprintf(buf, "%s\n", pdev->driver_override);
1022 device_unlock(dev);
1023 return len;
1024}
1025static DEVICE_ATTR_RW(driver_override);
1026
1027
1028static struct attribute *platform_dev_attrs[] = {
1029 &dev_attr_modalias.attr,
1030 &dev_attr_driver_override.attr,
1031 NULL,
1032};
1033ATTRIBUTE_GROUPS(platform_dev);
1034
1035static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
1036{
1037 struct platform_device *pdev = to_platform_device(dev);
1038 int rc;
1039
1040 /* Some devices have extra OF data and an OF-style MODALIAS */
1041 rc = of_device_uevent_modalias(dev, env);
1042 if (rc != -ENODEV)
1043 return rc;
1044
1045 rc = acpi_device_uevent_modalias(dev, env);
1046 if (rc != -ENODEV)
1047 return rc;
1048
1049 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
1050 pdev->name);
1051 return 0;
1052}
1053
1054static const struct platform_device_id *platform_match_id(
1055 const struct platform_device_id *id,
1056 struct platform_device *pdev)
1057{
1058 while (id->name[0]) {
1059 if (strcmp(pdev->name, id->name) == 0) {
1060 pdev->id_entry = id;
1061 return id;
1062 }
1063 id++;
1064 }
1065 return NULL;
1066}
1067
1068/**
1069 * platform_match - bind platform device to platform driver.
1070 * @dev: device.
1071 * @drv: driver.
1072 *
1073 * Platform device IDs are assumed to be encoded like this:
1074 * "<name><instance>", where <name> is a short description of the type of
1075 * device, like "pci" or "floppy", and <instance> is the enumerated
1076 * instance of the device, like '0' or '42'. Driver IDs are simply
1077 * "<name>". So, extract the <name> from the platform_device structure,
1078 * and compare it against the name of the driver. Return whether they match
1079 * or not.
1080 */
1081static int platform_match(struct device *dev, struct device_driver *drv)
1082{
1083 struct platform_device *pdev = to_platform_device(dev);
1084 struct platform_driver *pdrv = to_platform_driver(drv);
1085
1086 /* When driver_override is set, only bind to the matching driver */
1087 if (pdev->driver_override)
1088 return !strcmp(pdev->driver_override, drv->name);
1089
1090 /* Attempt an OF style match first */
1091 if (of_driver_match_device(dev, drv))
1092 return 1;
1093
1094 /* Then try ACPI style match */
1095 if (acpi_driver_match_device(dev, drv))
1096 return 1;
1097
1098 /* Then try to match against the id table */
1099 if (pdrv->id_table)
1100 return platform_match_id(pdrv->id_table, pdev) != NULL;
1101
1102 /* fall-back to driver name match */
1103 return (strcmp(pdev->name, drv->name) == 0);
1104}
1105
1106#ifdef CONFIG_PM_SLEEP
1107
1108static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
1109{
1110 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1111 struct platform_device *pdev = to_platform_device(dev);
1112 int ret = 0;
1113
1114 if (dev->driver && pdrv->suspend)
1115 ret = pdrv->suspend(pdev, mesg);
1116
1117 return ret;
1118}
1119
1120static int platform_legacy_resume(struct device *dev)
1121{
1122 struct platform_driver *pdrv = to_platform_driver(dev->driver);
1123 struct platform_device *pdev = to_platform_device(dev);
1124 int ret = 0;
1125
1126 if (dev->driver && pdrv->resume)
1127 ret = pdrv->resume(pdev);
1128
1129 return ret;
1130}
1131
1132#endif /* CONFIG_PM_SLEEP */
1133
1134#ifdef CONFIG_SUSPEND
1135
1136int platform_pm_suspend(struct device *dev)
1137{
1138 struct device_driver *drv = dev->driver;
1139 int ret = 0;
1140
1141 if (!drv)
1142 return 0;
1143
1144 if (drv->pm) {
1145 if (drv->pm->suspend)
1146 ret = drv->pm->suspend(dev);
1147 } else {
1148 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
1149 }
1150
1151 return ret;
1152}
1153
1154int platform_pm_resume(struct device *dev)
1155{
1156 struct device_driver *drv = dev->driver;
1157 int ret = 0;
1158
1159 if (!drv)
1160 return 0;
1161
1162 if (drv->pm) {
1163 if (drv->pm->resume)
1164 ret = drv->pm->resume(dev);
1165 } else {
1166 ret = platform_legacy_resume(dev);
1167 }
1168
1169 return ret;
1170}
1171
1172#endif /* CONFIG_SUSPEND */
1173
1174#ifdef CONFIG_HIBERNATE_CALLBACKS
1175
1176int platform_pm_freeze(struct device *dev)
1177{
1178 struct device_driver *drv = dev->driver;
1179 int ret = 0;
1180
1181 if (!drv)
1182 return 0;
1183
1184 if (drv->pm) {
1185 if (drv->pm->freeze)
1186 ret = drv->pm->freeze(dev);
1187 } else {
1188 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
1189 }
1190
1191 return ret;
1192}
1193
1194int platform_pm_thaw(struct device *dev)
1195{
1196 struct device_driver *drv = dev->driver;
1197 int ret = 0;
1198
1199 if (!drv)
1200 return 0;
1201
1202 if (drv->pm) {
1203 if (drv->pm->thaw)
1204 ret = drv->pm->thaw(dev);
1205 } else {
1206 ret = platform_legacy_resume(dev);
1207 }
1208
1209 return ret;
1210}
1211
1212int platform_pm_poweroff(struct device *dev)
1213{
1214 struct device_driver *drv = dev->driver;
1215 int ret = 0;
1216
1217 if (!drv)
1218 return 0;
1219
1220 if (drv->pm) {
1221 if (drv->pm->poweroff)
1222 ret = drv->pm->poweroff(dev);
1223 } else {
1224 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
1225 }
1226
1227 return ret;
1228}
1229
1230int platform_pm_restore(struct device *dev)
1231{
1232 struct device_driver *drv = dev->driver;
1233 int ret = 0;
1234
1235 if (!drv)
1236 return 0;
1237
1238 if (drv->pm) {
1239 if (drv->pm->restore)
1240 ret = drv->pm->restore(dev);
1241 } else {
1242 ret = platform_legacy_resume(dev);
1243 }
1244
1245 return ret;
1246}
1247
1248#endif /* CONFIG_HIBERNATE_CALLBACKS */
1249
1250int platform_dma_configure(struct device *dev)
1251{
1252 enum dev_dma_attr attr;
1253 int ret = 0;
1254
1255 if (dev->of_node) {
1256 ret = of_dma_configure(dev, dev->of_node, true);
1257 } else if (has_acpi_companion(dev)) {
1258 attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
1259 ret = acpi_dma_configure(dev, attr);
1260 }
1261
1262 return ret;
1263}
1264
1265static const struct dev_pm_ops platform_dev_pm_ops = {
1266 .runtime_suspend = pm_generic_runtime_suspend,
1267 .runtime_resume = pm_generic_runtime_resume,
1268 USE_PLATFORM_PM_SLEEP_OPS
1269};
1270
1271struct bus_type platform_bus_type = {
1272 .name = "platform",
1273 .dev_groups = platform_dev_groups,
1274 .match = platform_match,
1275 .uevent = platform_uevent,
1276 .dma_configure = platform_dma_configure,
1277 .pm = &platform_dev_pm_ops,
1278};
1279EXPORT_SYMBOL_GPL(platform_bus_type);
1280
1281/**
1282 * platform_find_device_by_driver - Find a platform device with a given
1283 * driver.
1284 * @start: The device to start the search from.
1285 * @drv: The device driver to look for.
1286 */
1287struct device *platform_find_device_by_driver(struct device *start,
1288 const struct device_driver *drv)
1289{
1290 return bus_find_device(&platform_bus_type, start, drv,
1291 (void *)platform_match);
1292}
1293EXPORT_SYMBOL_GPL(platform_find_device_by_driver);
1294
1295int __init platform_bus_init(void)
1296{
1297 int error;
1298
1299 early_platform_cleanup();
1300
1301 error = device_register(&platform_bus);
1302 if (error) {
1303 put_device(&platform_bus);
1304 return error;
1305 }
1306 error = bus_register(&platform_bus_type);
1307 if (error)
1308 device_unregister(&platform_bus);
1309 of_platform_register_reconfig_notifier();
1310 return error;
1311}
1312
1313static __initdata LIST_HEAD(early_platform_driver_list);
1314static __initdata LIST_HEAD(early_platform_device_list);
1315
1316/**
1317 * early_platform_driver_register - register early platform driver
1318 * @epdrv: early_platform driver structure
1319 * @buf: string passed from early_param()
1320 *
1321 * Helper function for early_platform_init() / early_platform_init_buffer()
1322 */
1323int __init early_platform_driver_register(struct early_platform_driver *epdrv,
1324 char *buf)
1325{
1326 char *tmp;
1327 int n;
1328
1329 /* Simply add the driver to the end of the global list.
1330 * Drivers will by default be put on the list in compiled-in order.
1331 */
1332 if (!epdrv->list.next) {
1333 INIT_LIST_HEAD(&epdrv->list);
1334 list_add_tail(&epdrv->list, &early_platform_driver_list);
1335 }
1336
1337 /* If the user has specified device then make sure the driver
1338 * gets prioritized. The driver of the last device specified on
1339 * command line will be put first on the list.
1340 */
1341 n = strlen(epdrv->pdrv->driver.name);
1342 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
1343 list_move(&epdrv->list, &early_platform_driver_list);
1344
1345 /* Allow passing parameters after device name */
1346 if (buf[n] == '\0' || buf[n] == ',')
1347 epdrv->requested_id = -1;
1348 else {
1349 epdrv->requested_id = simple_strtoul(&buf[n + 1],
1350 &tmp, 10);
1351
1352 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
1353 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
1354 n = 0;
1355 } else
1356 n += strcspn(&buf[n + 1], ",") + 1;
1357 }
1358
1359 if (buf[n] == ',')
1360 n++;
1361
1362 if (epdrv->bufsize) {
1363 memcpy(epdrv->buffer, &buf[n],
1364 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
1365 epdrv->buffer[epdrv->bufsize - 1] = '\0';
1366 }
1367 }
1368
1369 return 0;
1370}
1371
1372/**
1373 * early_platform_add_devices - adds a number of early platform devices
1374 * @devs: array of early platform devices to add
1375 * @num: number of early platform devices in array
1376 *
1377 * Used by early architecture code to register early platform devices and
1378 * their platform data.
1379 */
1380void __init early_platform_add_devices(struct platform_device **devs, int num)
1381{
1382 struct device *dev;
1383 int i;
1384
1385 /* simply add the devices to list */
1386 for (i = 0; i < num; i++) {
1387 dev = &devs[i]->dev;
1388
1389 if (!dev->devres_head.next) {
1390 pm_runtime_early_init(dev);
1391 INIT_LIST_HEAD(&dev->devres_head);
1392 list_add_tail(&dev->devres_head,
1393 &early_platform_device_list);
1394 }
1395 }
1396}
1397
1398/**
1399 * early_platform_driver_register_all - register early platform drivers
1400 * @class_str: string to identify early platform driver class
1401 *
1402 * Used by architecture code to register all early platform drivers
1403 * for a certain class. If omitted then only early platform drivers
1404 * with matching kernel command line class parameters will be registered.
1405 */
1406void __init early_platform_driver_register_all(char *class_str)
1407{
1408 /* The "class_str" parameter may or may not be present on the kernel
1409 * command line. If it is present then there may be more than one
1410 * matching parameter.
1411 *
1412 * Since we register our early platform drivers using early_param()
1413 * we need to make sure that they also get registered in the case
1414 * when the parameter is missing from the kernel command line.
1415 *
1416 * We use parse_early_options() to make sure the early_param() gets
1417 * called at least once. The early_param() may be called more than
1418 * once since the name of the preferred device may be specified on
1419 * the kernel command line. early_platform_driver_register() handles
1420 * this case for us.
1421 */
1422 parse_early_options(class_str);
1423}
1424
1425/**
1426 * early_platform_match - find early platform device matching driver
1427 * @epdrv: early platform driver structure
1428 * @id: id to match against
1429 */
1430static struct platform_device * __init
1431early_platform_match(struct early_platform_driver *epdrv, int id)
1432{
1433 struct platform_device *pd;
1434
1435 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1436 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1437 if (pd->id == id)
1438 return pd;
1439
1440 return NULL;
1441}
1442
1443/**
1444 * early_platform_left - check if early platform driver has matching devices
1445 * @epdrv: early platform driver structure
1446 * @id: return true if id or above exists
1447 */
1448static int __init early_platform_left(struct early_platform_driver *epdrv,
1449 int id)
1450{
1451 struct platform_device *pd;
1452
1453 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1454 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1455 if (pd->id >= id)
1456 return 1;
1457
1458 return 0;
1459}
1460
1461/**
1462 * early_platform_driver_probe_id - probe drivers matching class_str and id
1463 * @class_str: string to identify early platform driver class
1464 * @id: id to match against
1465 * @nr_probe: number of platform devices to successfully probe before exiting
1466 */
1467static int __init early_platform_driver_probe_id(char *class_str,
1468 int id,
1469 int nr_probe)
1470{
1471 struct early_platform_driver *epdrv;
1472 struct platform_device *match;
1473 int match_id;
1474 int n = 0;
1475 int left = 0;
1476
1477 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1478 /* only use drivers matching our class_str */
1479 if (strcmp(class_str, epdrv->class_str))
1480 continue;
1481
1482 if (id == -2) {
1483 match_id = epdrv->requested_id;
1484 left = 1;
1485
1486 } else {
1487 match_id = id;
1488 left += early_platform_left(epdrv, id);
1489
1490 /* skip requested id */
1491 switch (epdrv->requested_id) {
1492 case EARLY_PLATFORM_ID_ERROR:
1493 case EARLY_PLATFORM_ID_UNSET:
1494 break;
1495 default:
1496 if (epdrv->requested_id == id)
1497 match_id = EARLY_PLATFORM_ID_UNSET;
1498 }
1499 }
1500
1501 switch (match_id) {
1502 case EARLY_PLATFORM_ID_ERROR:
1503 pr_warn("%s: unable to parse %s parameter\n",
1504 class_str, epdrv->pdrv->driver.name);
1505 /* fall-through */
1506 case EARLY_PLATFORM_ID_UNSET:
1507 match = NULL;
1508 break;
1509 default:
1510 match = early_platform_match(epdrv, match_id);
1511 }
1512
1513 if (match) {
1514 /*
1515 * Set up a sensible init_name to enable
1516 * dev_name() and others to be used before the
1517 * rest of the driver core is initialized.
1518 */
1519 if (!match->dev.init_name && slab_is_available()) {
1520 if (match->id != -1)
1521 match->dev.init_name =
1522 kasprintf(GFP_KERNEL, "%s.%d",
1523 match->name,
1524 match->id);
1525 else
1526 match->dev.init_name =
1527 kasprintf(GFP_KERNEL, "%s",
1528 match->name);
1529
1530 if (!match->dev.init_name)
1531 return -ENOMEM;
1532 }
1533
1534 if (epdrv->pdrv->probe(match))
1535 pr_warn("%s: unable to probe %s early.\n",
1536 class_str, match->name);
1537 else
1538 n++;
1539 }
1540
1541 if (n >= nr_probe)
1542 break;
1543 }
1544
1545 if (left)
1546 return n;
1547 else
1548 return -ENODEV;
1549}
1550
1551/**
1552 * early_platform_driver_probe - probe a class of registered drivers
1553 * @class_str: string to identify early platform driver class
1554 * @nr_probe: number of platform devices to successfully probe before exiting
1555 * @user_only: only probe user specified early platform devices
1556 *
1557 * Used by architecture code to probe registered early platform drivers
1558 * within a certain class. For probe to happen a registered early platform
1559 * device matching a registered early platform driver is needed.
1560 */
1561int __init early_platform_driver_probe(char *class_str,
1562 int nr_probe,
1563 int user_only)
1564{
1565 int k, n, i;
1566
1567 n = 0;
1568 for (i = -2; n < nr_probe; i++) {
1569 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1570
1571 if (k < 0)
1572 break;
1573
1574 n += k;
1575
1576 if (user_only)
1577 break;
1578 }
1579
1580 return n;
1581}
1582
1583/**
1584 * early_platform_cleanup - clean up early platform code
1585 */
1586void __init early_platform_cleanup(void)
1587{
1588 struct platform_device *pd, *pd2;
1589
1590 /* clean up the devres list used to chain devices */
1591 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1592 dev.devres_head) {
1593 list_del(&pd->dev.devres_head);
1594 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1595 }
1596}
1597