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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/module.h>
17#include <linux/init.h>
18#include <linux/dma-mapping.h>
19#include <linux/bootmem.h>
20#include <linux/err.h>
21#include <linux/slab.h>
22#include <linux/pm_runtime.h>
23
24#include "base.h"
25
26#define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
27 driver))
28
29struct device platform_bus = {
30 .init_name = "platform",
31};
32EXPORT_SYMBOL_GPL(platform_bus);
33
34/**
35 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
36 * @pdev: platform device
37 *
38 * This is called before platform_device_add() such that any pdev_archdata may
39 * be setup before the platform_notifier is called. So if a user needs to
40 * manipulate any relevant information in the pdev_archdata they can do:
41 *
42 * platform_devic_alloc()
43 * ... manipulate ...
44 * platform_device_add()
45 *
46 * And if they don't care they can just call platform_device_register() and
47 * everything will just work out.
48 */
49void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
50{
51}
52
53/**
54 * platform_get_resource - get a resource for a device
55 * @dev: platform device
56 * @type: resource type
57 * @num: resource index
58 */
59struct resource *platform_get_resource(struct platform_device *dev,
60 unsigned int type, unsigned int num)
61{
62 int i;
63
64 for (i = 0; i < dev->num_resources; i++) {
65 struct resource *r = &dev->resource[i];
66
67 if (type == resource_type(r) && num-- == 0)
68 return r;
69 }
70 return NULL;
71}
72EXPORT_SYMBOL_GPL(platform_get_resource);
73
74/**
75 * platform_get_irq - get an IRQ for a device
76 * @dev: platform device
77 * @num: IRQ number index
78 */
79int platform_get_irq(struct platform_device *dev, unsigned int num)
80{
81 struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num);
82
83 return r ? r->start : -ENXIO;
84}
85EXPORT_SYMBOL_GPL(platform_get_irq);
86
87/**
88 * platform_get_resource_byname - get a resource for a device by name
89 * @dev: platform device
90 * @type: resource type
91 * @name: resource name
92 */
93struct resource *platform_get_resource_byname(struct platform_device *dev,
94 unsigned int type,
95 const char *name)
96{
97 int i;
98
99 for (i = 0; i < dev->num_resources; i++) {
100 struct resource *r = &dev->resource[i];
101
102 if (type == resource_type(r) && !strcmp(r->name, name))
103 return r;
104 }
105 return NULL;
106}
107EXPORT_SYMBOL_GPL(platform_get_resource_byname);
108
109/**
110 * platform_get_irq - get an IRQ for a device
111 * @dev: platform device
112 * @name: IRQ name
113 */
114int platform_get_irq_byname(struct platform_device *dev, const char *name)
115{
116 struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ,
117 name);
118
119 return r ? r->start : -ENXIO;
120}
121EXPORT_SYMBOL_GPL(platform_get_irq_byname);
122
123/**
124 * platform_add_devices - add a numbers of platform devices
125 * @devs: array of platform devices to add
126 * @num: number of platform devices in array
127 */
128int platform_add_devices(struct platform_device **devs, int num)
129{
130 int i, ret = 0;
131
132 for (i = 0; i < num; i++) {
133 ret = platform_device_register(devs[i]);
134 if (ret) {
135 while (--i >= 0)
136 platform_device_unregister(devs[i]);
137 break;
138 }
139 }
140
141 return ret;
142}
143EXPORT_SYMBOL_GPL(platform_add_devices);
144
145struct platform_object {
146 struct platform_device pdev;
147 char name[1];
148};
149
150/**
151 * platform_device_put - destroy a platform device
152 * @pdev: platform device to free
153 *
154 * Free all memory associated with a platform device. This function must
155 * _only_ be externally called in error cases. All other usage is a bug.
156 */
157void platform_device_put(struct platform_device *pdev)
158{
159 if (pdev)
160 put_device(&pdev->dev);
161}
162EXPORT_SYMBOL_GPL(platform_device_put);
163
164static void platform_device_release(struct device *dev)
165{
166 struct platform_object *pa = container_of(dev, struct platform_object,
167 pdev.dev);
168
169 of_device_node_put(&pa->pdev.dev);
170 kfree(pa->pdev.dev.platform_data);
171 kfree(pa->pdev.mfd_cell);
172 kfree(pa->pdev.resource);
173 kfree(pa);
174}
175
176/**
177 * platform_device_alloc - create a platform device
178 * @name: base name of the device we're adding
179 * @id: instance id
180 *
181 * Create a platform device object which can have other objects attached
182 * to it, and which will have attached objects freed when it is released.
183 */
184struct platform_device *platform_device_alloc(const char *name, int id)
185{
186 struct platform_object *pa;
187
188 pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL);
189 if (pa) {
190 strcpy(pa->name, name);
191 pa->pdev.name = pa->name;
192 pa->pdev.id = id;
193 device_initialize(&pa->pdev.dev);
194 pa->pdev.dev.release = platform_device_release;
195 arch_setup_pdev_archdata(&pa->pdev);
196 }
197
198 return pa ? &pa->pdev : NULL;
199}
200EXPORT_SYMBOL_GPL(platform_device_alloc);
201
202/**
203 * platform_device_add_resources - add resources to a platform device
204 * @pdev: platform device allocated by platform_device_alloc to add resources to
205 * @res: set of resources that needs to be allocated for the device
206 * @num: number of resources
207 *
208 * Add a copy of the resources to the platform device. The memory
209 * associated with the resources will be freed when the platform device is
210 * released.
211 */
212int platform_device_add_resources(struct platform_device *pdev,
213 const struct resource *res, unsigned int num)
214{
215 struct resource *r = NULL;
216
217 if (res) {
218 r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
219 if (!r)
220 return -ENOMEM;
221 }
222
223 kfree(pdev->resource);
224 pdev->resource = r;
225 pdev->num_resources = num;
226 return 0;
227}
228EXPORT_SYMBOL_GPL(platform_device_add_resources);
229
230/**
231 * platform_device_add_data - add platform-specific data to a platform device
232 * @pdev: platform device allocated by platform_device_alloc to add resources to
233 * @data: platform specific data for this platform device
234 * @size: size of platform specific data
235 *
236 * Add a copy of platform specific data to the platform device's
237 * platform_data pointer. The memory associated with the platform data
238 * will be freed when the platform device is released.
239 */
240int platform_device_add_data(struct platform_device *pdev, const void *data,
241 size_t size)
242{
243 void *d = NULL;
244
245 if (data) {
246 d = kmemdup(data, size, GFP_KERNEL);
247 if (!d)
248 return -ENOMEM;
249 }
250
251 kfree(pdev->dev.platform_data);
252 pdev->dev.platform_data = d;
253 return 0;
254}
255EXPORT_SYMBOL_GPL(platform_device_add_data);
256
257/**
258 * platform_device_add - add a platform device to device hierarchy
259 * @pdev: platform device we're adding
260 *
261 * This is part 2 of platform_device_register(), though may be called
262 * separately _iff_ pdev was allocated by platform_device_alloc().
263 */
264int platform_device_add(struct platform_device *pdev)
265{
266 int i, ret = 0;
267
268 if (!pdev)
269 return -EINVAL;
270
271 if (!pdev->dev.parent)
272 pdev->dev.parent = &platform_bus;
273
274 pdev->dev.bus = &platform_bus_type;
275
276 if (pdev->id != -1)
277 dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
278 else
279 dev_set_name(&pdev->dev, "%s", pdev->name);
280
281 for (i = 0; i < pdev->num_resources; i++) {
282 struct resource *p, *r = &pdev->resource[i];
283
284 if (r->name == NULL)
285 r->name = dev_name(&pdev->dev);
286
287 p = r->parent;
288 if (!p) {
289 if (resource_type(r) == IORESOURCE_MEM)
290 p = &iomem_resource;
291 else if (resource_type(r) == IORESOURCE_IO)
292 p = &ioport_resource;
293 }
294
295 if (p && insert_resource(p, r)) {
296 printk(KERN_ERR
297 "%s: failed to claim resource %d\n",
298 dev_name(&pdev->dev), i);
299 ret = -EBUSY;
300 goto failed;
301 }
302 }
303
304 pr_debug("Registering platform device '%s'. Parent at %s\n",
305 dev_name(&pdev->dev), dev_name(pdev->dev.parent));
306
307 ret = device_add(&pdev->dev);
308 if (ret == 0)
309 return ret;
310
311 failed:
312 while (--i >= 0) {
313 struct resource *r = &pdev->resource[i];
314 unsigned long type = resource_type(r);
315
316 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
317 release_resource(r);
318 }
319
320 return ret;
321}
322EXPORT_SYMBOL_GPL(platform_device_add);
323
324/**
325 * platform_device_del - remove a platform-level device
326 * @pdev: platform device we're removing
327 *
328 * Note that this function will also release all memory- and port-based
329 * resources owned by the device (@dev->resource). This function must
330 * _only_ be externally called in error cases. All other usage is a bug.
331 */
332void platform_device_del(struct platform_device *pdev)
333{
334 int i;
335
336 if (pdev) {
337 device_del(&pdev->dev);
338
339 for (i = 0; i < pdev->num_resources; i++) {
340 struct resource *r = &pdev->resource[i];
341 unsigned long type = resource_type(r);
342
343 if (type == IORESOURCE_MEM || type == IORESOURCE_IO)
344 release_resource(r);
345 }
346 }
347}
348EXPORT_SYMBOL_GPL(platform_device_del);
349
350/**
351 * platform_device_register - add a platform-level device
352 * @pdev: platform device we're adding
353 */
354int platform_device_register(struct platform_device *pdev)
355{
356 device_initialize(&pdev->dev);
357 arch_setup_pdev_archdata(pdev);
358 return platform_device_add(pdev);
359}
360EXPORT_SYMBOL_GPL(platform_device_register);
361
362/**
363 * platform_device_unregister - unregister a platform-level device
364 * @pdev: platform device we're unregistering
365 *
366 * Unregistration is done in 2 steps. First we release all resources
367 * and remove it from the subsystem, then we drop reference count by
368 * calling platform_device_put().
369 */
370void platform_device_unregister(struct platform_device *pdev)
371{
372 platform_device_del(pdev);
373 platform_device_put(pdev);
374}
375EXPORT_SYMBOL_GPL(platform_device_unregister);
376
377/**
378 * platform_device_register_full - add a platform-level device with
379 * resources and platform-specific data
380 *
381 * @pdevinfo: data used to create device
382 *
383 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
384 */
385struct platform_device *platform_device_register_full(
386 const struct platform_device_info *pdevinfo)
387{
388 int ret = -ENOMEM;
389 struct platform_device *pdev;
390
391 pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id);
392 if (!pdev)
393 goto err_alloc;
394
395 pdev->dev.parent = pdevinfo->parent;
396
397 if (pdevinfo->dma_mask) {
398 /*
399 * This memory isn't freed when the device is put,
400 * I don't have a nice idea for that though. Conceptually
401 * dma_mask in struct device should not be a pointer.
402 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
403 */
404 pdev->dev.dma_mask =
405 kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL);
406 if (!pdev->dev.dma_mask)
407 goto err;
408
409 *pdev->dev.dma_mask = pdevinfo->dma_mask;
410 pdev->dev.coherent_dma_mask = pdevinfo->dma_mask;
411 }
412
413 ret = platform_device_add_resources(pdev,
414 pdevinfo->res, pdevinfo->num_res);
415 if (ret)
416 goto err;
417
418 ret = platform_device_add_data(pdev,
419 pdevinfo->data, pdevinfo->size_data);
420 if (ret)
421 goto err;
422
423 ret = platform_device_add(pdev);
424 if (ret) {
425err:
426 kfree(pdev->dev.dma_mask);
427
428err_alloc:
429 platform_device_put(pdev);
430 return ERR_PTR(ret);
431 }
432
433 return pdev;
434}
435EXPORT_SYMBOL_GPL(platform_device_register_full);
436
437static int platform_drv_probe(struct device *_dev)
438{
439 struct platform_driver *drv = to_platform_driver(_dev->driver);
440 struct platform_device *dev = to_platform_device(_dev);
441
442 return drv->probe(dev);
443}
444
445static int platform_drv_probe_fail(struct device *_dev)
446{
447 return -ENXIO;
448}
449
450static int platform_drv_remove(struct device *_dev)
451{
452 struct platform_driver *drv = to_platform_driver(_dev->driver);
453 struct platform_device *dev = to_platform_device(_dev);
454
455 return drv->remove(dev);
456}
457
458static void platform_drv_shutdown(struct device *_dev)
459{
460 struct platform_driver *drv = to_platform_driver(_dev->driver);
461 struct platform_device *dev = to_platform_device(_dev);
462
463 drv->shutdown(dev);
464}
465
466/**
467 * platform_driver_register - register a driver for platform-level devices
468 * @drv: platform driver structure
469 */
470int platform_driver_register(struct platform_driver *drv)
471{
472 drv->driver.bus = &platform_bus_type;
473 if (drv->probe)
474 drv->driver.probe = platform_drv_probe;
475 if (drv->remove)
476 drv->driver.remove = platform_drv_remove;
477 if (drv->shutdown)
478 drv->driver.shutdown = platform_drv_shutdown;
479
480 return driver_register(&drv->driver);
481}
482EXPORT_SYMBOL_GPL(platform_driver_register);
483
484/**
485 * platform_driver_unregister - unregister a driver for platform-level devices
486 * @drv: platform driver structure
487 */
488void platform_driver_unregister(struct platform_driver *drv)
489{
490 driver_unregister(&drv->driver);
491}
492EXPORT_SYMBOL_GPL(platform_driver_unregister);
493
494/**
495 * platform_driver_probe - register driver for non-hotpluggable device
496 * @drv: platform driver structure
497 * @probe: the driver probe routine, probably from an __init section
498 *
499 * Use this instead of platform_driver_register() when you know the device
500 * is not hotpluggable and has already been registered, and you want to
501 * remove its run-once probe() infrastructure from memory after the driver
502 * has bound to the device.
503 *
504 * One typical use for this would be with drivers for controllers integrated
505 * into system-on-chip processors, where the controller devices have been
506 * configured as part of board setup.
507 *
508 * Returns zero if the driver registered and bound to a device, else returns
509 * a negative error code and with the driver not registered.
510 */
511int __init_or_module platform_driver_probe(struct platform_driver *drv,
512 int (*probe)(struct platform_device *))
513{
514 int retval, code;
515
516 /* make sure driver won't have bind/unbind attributes */
517 drv->driver.suppress_bind_attrs = true;
518
519 /* temporary section violation during probe() */
520 drv->probe = probe;
521 retval = code = platform_driver_register(drv);
522
523 /*
524 * Fixup that section violation, being paranoid about code scanning
525 * the list of drivers in order to probe new devices. Check to see
526 * if the probe was successful, and make sure any forced probes of
527 * new devices fail.
528 */
529 spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
530 drv->probe = NULL;
531 if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
532 retval = -ENODEV;
533 drv->driver.probe = platform_drv_probe_fail;
534 spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
535
536 if (code != retval)
537 platform_driver_unregister(drv);
538 return retval;
539}
540EXPORT_SYMBOL_GPL(platform_driver_probe);
541
542/**
543 * platform_create_bundle - register driver and create corresponding device
544 * @driver: platform driver structure
545 * @probe: the driver probe routine, probably from an __init section
546 * @res: set of resources that needs to be allocated for the device
547 * @n_res: number of resources
548 * @data: platform specific data for this platform device
549 * @size: size of platform specific data
550 *
551 * Use this in legacy-style modules that probe hardware directly and
552 * register a single platform device and corresponding platform driver.
553 *
554 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
555 */
556struct platform_device * __init_or_module platform_create_bundle(
557 struct platform_driver *driver,
558 int (*probe)(struct platform_device *),
559 struct resource *res, unsigned int n_res,
560 const void *data, size_t size)
561{
562 struct platform_device *pdev;
563 int error;
564
565 pdev = platform_device_alloc(driver->driver.name, -1);
566 if (!pdev) {
567 error = -ENOMEM;
568 goto err_out;
569 }
570
571 error = platform_device_add_resources(pdev, res, n_res);
572 if (error)
573 goto err_pdev_put;
574
575 error = platform_device_add_data(pdev, data, size);
576 if (error)
577 goto err_pdev_put;
578
579 error = platform_device_add(pdev);
580 if (error)
581 goto err_pdev_put;
582
583 error = platform_driver_probe(driver, probe);
584 if (error)
585 goto err_pdev_del;
586
587 return pdev;
588
589err_pdev_del:
590 platform_device_del(pdev);
591err_pdev_put:
592 platform_device_put(pdev);
593err_out:
594 return ERR_PTR(error);
595}
596EXPORT_SYMBOL_GPL(platform_create_bundle);
597
598/* modalias support enables more hands-off userspace setup:
599 * (a) environment variable lets new-style hotplug events work once system is
600 * fully running: "modprobe $MODALIAS"
601 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
602 * mishandled before system is fully running: "modprobe $(cat modalias)"
603 */
604static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
605 char *buf)
606{
607 struct platform_device *pdev = to_platform_device(dev);
608 int len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name);
609
610 return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
611}
612
613static struct device_attribute platform_dev_attrs[] = {
614 __ATTR_RO(modalias),
615 __ATTR_NULL,
616};
617
618static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
619{
620 struct platform_device *pdev = to_platform_device(dev);
621 int rc;
622
623 /* Some devices have extra OF data and an OF-style MODALIAS */
624 rc = of_device_uevent_modalias(dev,env);
625 if (rc != -ENODEV)
626 return rc;
627
628 add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
629 pdev->name);
630 return 0;
631}
632
633static const struct platform_device_id *platform_match_id(
634 const struct platform_device_id *id,
635 struct platform_device *pdev)
636{
637 while (id->name[0]) {
638 if (strcmp(pdev->name, id->name) == 0) {
639 pdev->id_entry = id;
640 return id;
641 }
642 id++;
643 }
644 return NULL;
645}
646
647/**
648 * platform_match - bind platform device to platform driver.
649 * @dev: device.
650 * @drv: driver.
651 *
652 * Platform device IDs are assumed to be encoded like this:
653 * "<name><instance>", where <name> is a short description of the type of
654 * device, like "pci" or "floppy", and <instance> is the enumerated
655 * instance of the device, like '0' or '42'. Driver IDs are simply
656 * "<name>". So, extract the <name> from the platform_device structure,
657 * and compare it against the name of the driver. Return whether they match
658 * or not.
659 */
660static int platform_match(struct device *dev, struct device_driver *drv)
661{
662 struct platform_device *pdev = to_platform_device(dev);
663 struct platform_driver *pdrv = to_platform_driver(drv);
664
665 /* Attempt an OF style match first */
666 if (of_driver_match_device(dev, drv))
667 return 1;
668
669 /* Then try to match against the id table */
670 if (pdrv->id_table)
671 return platform_match_id(pdrv->id_table, pdev) != NULL;
672
673 /* fall-back to driver name match */
674 return (strcmp(pdev->name, drv->name) == 0);
675}
676
677#ifdef CONFIG_PM_SLEEP
678
679static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
680{
681 struct platform_driver *pdrv = to_platform_driver(dev->driver);
682 struct platform_device *pdev = to_platform_device(dev);
683 int ret = 0;
684
685 if (dev->driver && pdrv->suspend)
686 ret = pdrv->suspend(pdev, mesg);
687
688 return ret;
689}
690
691static int platform_legacy_resume(struct device *dev)
692{
693 struct platform_driver *pdrv = to_platform_driver(dev->driver);
694 struct platform_device *pdev = to_platform_device(dev);
695 int ret = 0;
696
697 if (dev->driver && pdrv->resume)
698 ret = pdrv->resume(pdev);
699
700 return ret;
701}
702
703#endif /* CONFIG_PM_SLEEP */
704
705#ifdef CONFIG_SUSPEND
706
707int platform_pm_suspend(struct device *dev)
708{
709 struct device_driver *drv = dev->driver;
710 int ret = 0;
711
712 if (!drv)
713 return 0;
714
715 if (drv->pm) {
716 if (drv->pm->suspend)
717 ret = drv->pm->suspend(dev);
718 } else {
719 ret = platform_legacy_suspend(dev, PMSG_SUSPEND);
720 }
721
722 return ret;
723}
724
725int platform_pm_resume(struct device *dev)
726{
727 struct device_driver *drv = dev->driver;
728 int ret = 0;
729
730 if (!drv)
731 return 0;
732
733 if (drv->pm) {
734 if (drv->pm->resume)
735 ret = drv->pm->resume(dev);
736 } else {
737 ret = platform_legacy_resume(dev);
738 }
739
740 return ret;
741}
742
743#endif /* CONFIG_SUSPEND */
744
745#ifdef CONFIG_HIBERNATE_CALLBACKS
746
747int platform_pm_freeze(struct device *dev)
748{
749 struct device_driver *drv = dev->driver;
750 int ret = 0;
751
752 if (!drv)
753 return 0;
754
755 if (drv->pm) {
756 if (drv->pm->freeze)
757 ret = drv->pm->freeze(dev);
758 } else {
759 ret = platform_legacy_suspend(dev, PMSG_FREEZE);
760 }
761
762 return ret;
763}
764
765int platform_pm_thaw(struct device *dev)
766{
767 struct device_driver *drv = dev->driver;
768 int ret = 0;
769
770 if (!drv)
771 return 0;
772
773 if (drv->pm) {
774 if (drv->pm->thaw)
775 ret = drv->pm->thaw(dev);
776 } else {
777 ret = platform_legacy_resume(dev);
778 }
779
780 return ret;
781}
782
783int platform_pm_poweroff(struct device *dev)
784{
785 struct device_driver *drv = dev->driver;
786 int ret = 0;
787
788 if (!drv)
789 return 0;
790
791 if (drv->pm) {
792 if (drv->pm->poweroff)
793 ret = drv->pm->poweroff(dev);
794 } else {
795 ret = platform_legacy_suspend(dev, PMSG_HIBERNATE);
796 }
797
798 return ret;
799}
800
801int platform_pm_restore(struct device *dev)
802{
803 struct device_driver *drv = dev->driver;
804 int ret = 0;
805
806 if (!drv)
807 return 0;
808
809 if (drv->pm) {
810 if (drv->pm->restore)
811 ret = drv->pm->restore(dev);
812 } else {
813 ret = platform_legacy_resume(dev);
814 }
815
816 return ret;
817}
818
819#endif /* CONFIG_HIBERNATE_CALLBACKS */
820
821static const struct dev_pm_ops platform_dev_pm_ops = {
822 .runtime_suspend = pm_generic_runtime_suspend,
823 .runtime_resume = pm_generic_runtime_resume,
824 .runtime_idle = pm_generic_runtime_idle,
825 USE_PLATFORM_PM_SLEEP_OPS
826};
827
828struct bus_type platform_bus_type = {
829 .name = "platform",
830 .dev_attrs = platform_dev_attrs,
831 .match = platform_match,
832 .uevent = platform_uevent,
833 .pm = &platform_dev_pm_ops,
834};
835EXPORT_SYMBOL_GPL(platform_bus_type);
836
837int __init platform_bus_init(void)
838{
839 int error;
840
841 early_platform_cleanup();
842
843 error = device_register(&platform_bus);
844 if (error)
845 return error;
846 error = bus_register(&platform_bus_type);
847 if (error)
848 device_unregister(&platform_bus);
849 return error;
850}
851
852#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
853u64 dma_get_required_mask(struct device *dev)
854{
855 u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
856 u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
857 u64 mask;
858
859 if (!high_totalram) {
860 /* convert to mask just covering totalram */
861 low_totalram = (1 << (fls(low_totalram) - 1));
862 low_totalram += low_totalram - 1;
863 mask = low_totalram;
864 } else {
865 high_totalram = (1 << (fls(high_totalram) - 1));
866 high_totalram += high_totalram - 1;
867 mask = (((u64)high_totalram) << 32) + 0xffffffff;
868 }
869 return mask;
870}
871EXPORT_SYMBOL_GPL(dma_get_required_mask);
872#endif
873
874static __initdata LIST_HEAD(early_platform_driver_list);
875static __initdata LIST_HEAD(early_platform_device_list);
876
877/**
878 * early_platform_driver_register - register early platform driver
879 * @epdrv: early_platform driver structure
880 * @buf: string passed from early_param()
881 *
882 * Helper function for early_platform_init() / early_platform_init_buffer()
883 */
884int __init early_platform_driver_register(struct early_platform_driver *epdrv,
885 char *buf)
886{
887 char *tmp;
888 int n;
889
890 /* Simply add the driver to the end of the global list.
891 * Drivers will by default be put on the list in compiled-in order.
892 */
893 if (!epdrv->list.next) {
894 INIT_LIST_HEAD(&epdrv->list);
895 list_add_tail(&epdrv->list, &early_platform_driver_list);
896 }
897
898 /* If the user has specified device then make sure the driver
899 * gets prioritized. The driver of the last device specified on
900 * command line will be put first on the list.
901 */
902 n = strlen(epdrv->pdrv->driver.name);
903 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
904 list_move(&epdrv->list, &early_platform_driver_list);
905
906 /* Allow passing parameters after device name */
907 if (buf[n] == '\0' || buf[n] == ',')
908 epdrv->requested_id = -1;
909 else {
910 epdrv->requested_id = simple_strtoul(&buf[n + 1],
911 &tmp, 10);
912
913 if (buf[n] != '.' || (tmp == &buf[n + 1])) {
914 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
915 n = 0;
916 } else
917 n += strcspn(&buf[n + 1], ",") + 1;
918 }
919
920 if (buf[n] == ',')
921 n++;
922
923 if (epdrv->bufsize) {
924 memcpy(epdrv->buffer, &buf[n],
925 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
926 epdrv->buffer[epdrv->bufsize - 1] = '\0';
927 }
928 }
929
930 return 0;
931}
932
933/**
934 * early_platform_add_devices - adds a number of early platform devices
935 * @devs: array of early platform devices to add
936 * @num: number of early platform devices in array
937 *
938 * Used by early architecture code to register early platform devices and
939 * their platform data.
940 */
941void __init early_platform_add_devices(struct platform_device **devs, int num)
942{
943 struct device *dev;
944 int i;
945
946 /* simply add the devices to list */
947 for (i = 0; i < num; i++) {
948 dev = &devs[i]->dev;
949
950 if (!dev->devres_head.next) {
951 INIT_LIST_HEAD(&dev->devres_head);
952 list_add_tail(&dev->devres_head,
953 &early_platform_device_list);
954 }
955 }
956}
957
958/**
959 * early_platform_driver_register_all - register early platform drivers
960 * @class_str: string to identify early platform driver class
961 *
962 * Used by architecture code to register all early platform drivers
963 * for a certain class. If omitted then only early platform drivers
964 * with matching kernel command line class parameters will be registered.
965 */
966void __init early_platform_driver_register_all(char *class_str)
967{
968 /* The "class_str" parameter may or may not be present on the kernel
969 * command line. If it is present then there may be more than one
970 * matching parameter.
971 *
972 * Since we register our early platform drivers using early_param()
973 * we need to make sure that they also get registered in the case
974 * when the parameter is missing from the kernel command line.
975 *
976 * We use parse_early_options() to make sure the early_param() gets
977 * called at least once. The early_param() may be called more than
978 * once since the name of the preferred device may be specified on
979 * the kernel command line. early_platform_driver_register() handles
980 * this case for us.
981 */
982 parse_early_options(class_str);
983}
984
985/**
986 * early_platform_match - find early platform device matching driver
987 * @epdrv: early platform driver structure
988 * @id: id to match against
989 */
990static __init struct platform_device *
991early_platform_match(struct early_platform_driver *epdrv, int id)
992{
993 struct platform_device *pd;
994
995 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
996 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
997 if (pd->id == id)
998 return pd;
999
1000 return NULL;
1001}
1002
1003/**
1004 * early_platform_left - check if early platform driver has matching devices
1005 * @epdrv: early platform driver structure
1006 * @id: return true if id or above exists
1007 */
1008static __init int early_platform_left(struct early_platform_driver *epdrv,
1009 int id)
1010{
1011 struct platform_device *pd;
1012
1013 list_for_each_entry(pd, &early_platform_device_list, dev.devres_head)
1014 if (platform_match(&pd->dev, &epdrv->pdrv->driver))
1015 if (pd->id >= id)
1016 return 1;
1017
1018 return 0;
1019}
1020
1021/**
1022 * early_platform_driver_probe_id - probe drivers matching class_str and id
1023 * @class_str: string to identify early platform driver class
1024 * @id: id to match against
1025 * @nr_probe: number of platform devices to successfully probe before exiting
1026 */
1027static int __init early_platform_driver_probe_id(char *class_str,
1028 int id,
1029 int nr_probe)
1030{
1031 struct early_platform_driver *epdrv;
1032 struct platform_device *match;
1033 int match_id;
1034 int n = 0;
1035 int left = 0;
1036
1037 list_for_each_entry(epdrv, &early_platform_driver_list, list) {
1038 /* only use drivers matching our class_str */
1039 if (strcmp(class_str, epdrv->class_str))
1040 continue;
1041
1042 if (id == -2) {
1043 match_id = epdrv->requested_id;
1044 left = 1;
1045
1046 } else {
1047 match_id = id;
1048 left += early_platform_left(epdrv, id);
1049
1050 /* skip requested id */
1051 switch (epdrv->requested_id) {
1052 case EARLY_PLATFORM_ID_ERROR:
1053 case EARLY_PLATFORM_ID_UNSET:
1054 break;
1055 default:
1056 if (epdrv->requested_id == id)
1057 match_id = EARLY_PLATFORM_ID_UNSET;
1058 }
1059 }
1060
1061 switch (match_id) {
1062 case EARLY_PLATFORM_ID_ERROR:
1063 pr_warning("%s: unable to parse %s parameter\n",
1064 class_str, epdrv->pdrv->driver.name);
1065 /* fall-through */
1066 case EARLY_PLATFORM_ID_UNSET:
1067 match = NULL;
1068 break;
1069 default:
1070 match = early_platform_match(epdrv, match_id);
1071 }
1072
1073 if (match) {
1074 /*
1075 * Set up a sensible init_name to enable
1076 * dev_name() and others to be used before the
1077 * rest of the driver core is initialized.
1078 */
1079 if (!match->dev.init_name && slab_is_available()) {
1080 if (match->id != -1)
1081 match->dev.init_name =
1082 kasprintf(GFP_KERNEL, "%s.%d",
1083 match->name,
1084 match->id);
1085 else
1086 match->dev.init_name =
1087 kasprintf(GFP_KERNEL, "%s",
1088 match->name);
1089
1090 if (!match->dev.init_name)
1091 return -ENOMEM;
1092 }
1093
1094 if (epdrv->pdrv->probe(match))
1095 pr_warning("%s: unable to probe %s early.\n",
1096 class_str, match->name);
1097 else
1098 n++;
1099 }
1100
1101 if (n >= nr_probe)
1102 break;
1103 }
1104
1105 if (left)
1106 return n;
1107 else
1108 return -ENODEV;
1109}
1110
1111/**
1112 * early_platform_driver_probe - probe a class of registered drivers
1113 * @class_str: string to identify early platform driver class
1114 * @nr_probe: number of platform devices to successfully probe before exiting
1115 * @user_only: only probe user specified early platform devices
1116 *
1117 * Used by architecture code to probe registered early platform drivers
1118 * within a certain class. For probe to happen a registered early platform
1119 * device matching a registered early platform driver is needed.
1120 */
1121int __init early_platform_driver_probe(char *class_str,
1122 int nr_probe,
1123 int user_only)
1124{
1125 int k, n, i;
1126
1127 n = 0;
1128 for (i = -2; n < nr_probe; i++) {
1129 k = early_platform_driver_probe_id(class_str, i, nr_probe - n);
1130
1131 if (k < 0)
1132 break;
1133
1134 n += k;
1135
1136 if (user_only)
1137 break;
1138 }
1139
1140 return n;
1141}
1142
1143/**
1144 * early_platform_cleanup - clean up early platform code
1145 */
1146void __init early_platform_cleanup(void)
1147{
1148 struct platform_device *pd, *pd2;
1149
1150 /* clean up the devres list used to chain devices */
1151 list_for_each_entry_safe(pd, pd2, &early_platform_device_list,
1152 dev.devres_head) {
1153 list_del(&pd->dev.devres_head);
1154 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
1155 }
1156}
1157