2 * platform.c - platform 'pseudo' bus for legacy devices
4 * Copyright (c) 2002-3 Patrick Mochel
5 * Copyright (c) 2002-3 Open Source Development Labs
7 * This file is released under the GPLv2
9 * Please see Documentation/driver-model/platform.txt for more
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 #include <linux/idr.h>
24 #include <linux/acpi.h>
27 #include "power/power.h"
29 /* For automatically allocated device IDs */
30 static DEFINE_IDA(platform_devid_ida
);
32 #define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
35 struct device platform_bus
= {
36 .init_name
= "platform",
38 EXPORT_SYMBOL_GPL(platform_bus
);
41 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
42 * @pdev: platform device
44 * This is called before platform_device_add() such that any pdev_archdata may
45 * be setup before the platform_notifier is called. So if a user needs to
46 * manipulate any relevant information in the pdev_archdata they can do:
48 * platform_device_alloc()
50 * platform_device_add()
52 * And if they don't care they can just call platform_device_register() and
53 * everything will just work out.
55 void __weak
arch_setup_pdev_archdata(struct platform_device
*pdev
)
60 * platform_get_resource - get a resource for a device
61 * @dev: platform device
62 * @type: resource type
63 * @num: resource index
65 struct resource
*platform_get_resource(struct platform_device
*dev
,
66 unsigned int type
, unsigned int num
)
70 for (i
= 0; i
< dev
->num_resources
; i
++) {
71 struct resource
*r
= &dev
->resource
[i
];
73 if (type
== resource_type(r
) && num
-- == 0)
78 EXPORT_SYMBOL_GPL(platform_get_resource
);
81 * platform_get_irq - get an IRQ for a device
82 * @dev: platform device
83 * @num: IRQ number index
85 int platform_get_irq(struct platform_device
*dev
, unsigned int num
)
88 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
89 if (!dev
|| num
>= dev
->archdata
.num_irqs
)
91 return dev
->archdata
.irqs
[num
];
93 struct resource
*r
= platform_get_resource(dev
, IORESOURCE_IRQ
, num
);
95 return r
? r
->start
: -ENXIO
;
98 EXPORT_SYMBOL_GPL(platform_get_irq
);
101 * platform_get_resource_byname - get a resource for a device by name
102 * @dev: platform device
103 * @type: resource type
104 * @name: resource name
106 struct resource
*platform_get_resource_byname(struct platform_device
*dev
,
112 for (i
= 0; i
< dev
->num_resources
; i
++) {
113 struct resource
*r
= &dev
->resource
[i
];
115 if (unlikely(!r
->name
))
118 if (type
== resource_type(r
) && !strcmp(r
->name
, name
))
123 EXPORT_SYMBOL_GPL(platform_get_resource_byname
);
126 * platform_get_irq_byname - get an IRQ for a device by name
127 * @dev: platform device
130 int platform_get_irq_byname(struct platform_device
*dev
, const char *name
)
132 struct resource
*r
= platform_get_resource_byname(dev
, IORESOURCE_IRQ
,
135 return r
? r
->start
: -ENXIO
;
137 EXPORT_SYMBOL_GPL(platform_get_irq_byname
);
140 * platform_add_devices - add a numbers of platform devices
141 * @devs: array of platform devices to add
142 * @num: number of platform devices in array
144 int platform_add_devices(struct platform_device
**devs
, int num
)
148 for (i
= 0; i
< num
; i
++) {
149 ret
= platform_device_register(devs
[i
]);
152 platform_device_unregister(devs
[i
]);
159 EXPORT_SYMBOL_GPL(platform_add_devices
);
161 struct platform_object
{
162 struct platform_device pdev
;
167 * platform_device_put - destroy a platform device
168 * @pdev: platform device to free
170 * Free all memory associated with a platform device. This function must
171 * _only_ be externally called in error cases. All other usage is a bug.
173 void platform_device_put(struct platform_device
*pdev
)
176 put_device(&pdev
->dev
);
178 EXPORT_SYMBOL_GPL(platform_device_put
);
180 static void platform_device_release(struct device
*dev
)
182 struct platform_object
*pa
= container_of(dev
, struct platform_object
,
185 of_device_node_put(&pa
->pdev
.dev
);
186 kfree(pa
->pdev
.dev
.platform_data
);
187 kfree(pa
->pdev
.mfd_cell
);
188 kfree(pa
->pdev
.resource
);
193 * platform_device_alloc - create a platform device
194 * @name: base name of the device we're adding
197 * Create a platform device object which can have other objects attached
198 * to it, and which will have attached objects freed when it is released.
200 struct platform_device
*platform_device_alloc(const char *name
, int id
)
202 struct platform_object
*pa
;
204 pa
= kzalloc(sizeof(struct platform_object
) + strlen(name
), GFP_KERNEL
);
206 strcpy(pa
->name
, name
);
207 pa
->pdev
.name
= pa
->name
;
209 device_initialize(&pa
->pdev
.dev
);
210 pa
->pdev
.dev
.release
= platform_device_release
;
211 arch_setup_pdev_archdata(&pa
->pdev
);
214 return pa
? &pa
->pdev
: NULL
;
216 EXPORT_SYMBOL_GPL(platform_device_alloc
);
219 * platform_device_add_resources - add resources to a platform device
220 * @pdev: platform device allocated by platform_device_alloc to add resources to
221 * @res: set of resources that needs to be allocated for the device
222 * @num: number of resources
224 * Add a copy of the resources to the platform device. The memory
225 * associated with the resources will be freed when the platform device is
228 int platform_device_add_resources(struct platform_device
*pdev
,
229 const struct resource
*res
, unsigned int num
)
231 struct resource
*r
= NULL
;
234 r
= kmemdup(res
, sizeof(struct resource
) * num
, GFP_KERNEL
);
239 kfree(pdev
->resource
);
241 pdev
->num_resources
= num
;
244 EXPORT_SYMBOL_GPL(platform_device_add_resources
);
247 * platform_device_add_data - add platform-specific data to a platform device
248 * @pdev: platform device allocated by platform_device_alloc to add resources to
249 * @data: platform specific data for this platform device
250 * @size: size of platform specific data
252 * Add a copy of platform specific data to the platform device's
253 * platform_data pointer. The memory associated with the platform data
254 * will be freed when the platform device is released.
256 int platform_device_add_data(struct platform_device
*pdev
, const void *data
,
262 d
= kmemdup(data
, size
, GFP_KERNEL
);
267 kfree(pdev
->dev
.platform_data
);
268 pdev
->dev
.platform_data
= d
;
271 EXPORT_SYMBOL_GPL(platform_device_add_data
);
274 * platform_device_add - add a platform device to device hierarchy
275 * @pdev: platform device we're adding
277 * This is part 2 of platform_device_register(), though may be called
278 * separately _iff_ pdev was allocated by platform_device_alloc().
280 int platform_device_add(struct platform_device
*pdev
)
287 if (!pdev
->dev
.parent
)
288 pdev
->dev
.parent
= &platform_bus
;
290 pdev
->dev
.bus
= &platform_bus_type
;
294 dev_set_name(&pdev
->dev
, "%s.%d", pdev
->name
, pdev
->id
);
296 case PLATFORM_DEVID_NONE
:
297 dev_set_name(&pdev
->dev
, "%s", pdev
->name
);
299 case PLATFORM_DEVID_AUTO
:
301 * Automatically allocated device ID. We mark it as such so
302 * that we remember it must be freed, and we append a suffix
303 * to avoid namespace collision with explicit IDs.
305 ret
= ida_simple_get(&platform_devid_ida
, 0, 0, GFP_KERNEL
);
309 pdev
->id_auto
= true;
310 dev_set_name(&pdev
->dev
, "%s.%d.auto", pdev
->name
, pdev
->id
);
314 for (i
= 0; i
< pdev
->num_resources
; i
++) {
315 struct resource
*p
, *r
= &pdev
->resource
[i
];
318 r
->name
= dev_name(&pdev
->dev
);
322 if (resource_type(r
) == IORESOURCE_MEM
)
324 else if (resource_type(r
) == IORESOURCE_IO
)
325 p
= &ioport_resource
;
328 if (p
&& insert_resource(p
, r
)) {
329 dev_err(&pdev
->dev
, "failed to claim resource %d\n", i
);
335 pr_debug("Registering platform device '%s'. Parent at %s\n",
336 dev_name(&pdev
->dev
), dev_name(pdev
->dev
.parent
));
338 ret
= device_add(&pdev
->dev
);
344 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
345 pdev
->id
= PLATFORM_DEVID_AUTO
;
349 struct resource
*r
= &pdev
->resource
[i
];
350 unsigned long type
= resource_type(r
);
352 if (type
== IORESOURCE_MEM
|| type
== IORESOURCE_IO
)
359 EXPORT_SYMBOL_GPL(platform_device_add
);
362 * platform_device_del - remove a platform-level device
363 * @pdev: platform device we're removing
365 * Note that this function will also release all memory- and port-based
366 * resources owned by the device (@dev->resource). This function must
367 * _only_ be externally called in error cases. All other usage is a bug.
369 void platform_device_del(struct platform_device
*pdev
)
374 device_del(&pdev
->dev
);
377 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
378 pdev
->id
= PLATFORM_DEVID_AUTO
;
381 for (i
= 0; i
< pdev
->num_resources
; i
++) {
382 struct resource
*r
= &pdev
->resource
[i
];
383 unsigned long type
= resource_type(r
);
385 if (type
== IORESOURCE_MEM
|| type
== IORESOURCE_IO
)
390 EXPORT_SYMBOL_GPL(platform_device_del
);
393 * platform_device_register - add a platform-level device
394 * @pdev: platform device we're adding
396 int platform_device_register(struct platform_device
*pdev
)
398 device_initialize(&pdev
->dev
);
399 arch_setup_pdev_archdata(pdev
);
400 return platform_device_add(pdev
);
402 EXPORT_SYMBOL_GPL(platform_device_register
);
405 * platform_device_unregister - unregister a platform-level device
406 * @pdev: platform device we're unregistering
408 * Unregistration is done in 2 steps. First we release all resources
409 * and remove it from the subsystem, then we drop reference count by
410 * calling platform_device_put().
412 void platform_device_unregister(struct platform_device
*pdev
)
414 platform_device_del(pdev
);
415 platform_device_put(pdev
);
417 EXPORT_SYMBOL_GPL(platform_device_unregister
);
420 * platform_device_register_full - add a platform-level device with
421 * resources and platform-specific data
423 * @pdevinfo: data used to create device
425 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
427 struct platform_device
*platform_device_register_full(
428 const struct platform_device_info
*pdevinfo
)
431 struct platform_device
*pdev
;
433 pdev
= platform_device_alloc(pdevinfo
->name
, pdevinfo
->id
);
437 pdev
->dev
.parent
= pdevinfo
->parent
;
438 ACPI_HANDLE_SET(&pdev
->dev
, pdevinfo
->acpi_node
.handle
);
440 if (pdevinfo
->dma_mask
) {
442 * This memory isn't freed when the device is put,
443 * I don't have a nice idea for that though. Conceptually
444 * dma_mask in struct device should not be a pointer.
445 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
448 kmalloc(sizeof(*pdev
->dev
.dma_mask
), GFP_KERNEL
);
449 if (!pdev
->dev
.dma_mask
)
452 *pdev
->dev
.dma_mask
= pdevinfo
->dma_mask
;
453 pdev
->dev
.coherent_dma_mask
= pdevinfo
->dma_mask
;
456 ret
= platform_device_add_resources(pdev
,
457 pdevinfo
->res
, pdevinfo
->num_res
);
461 ret
= platform_device_add_data(pdev
,
462 pdevinfo
->data
, pdevinfo
->size_data
);
466 ret
= platform_device_add(pdev
);
469 ACPI_HANDLE_SET(&pdev
->dev
, NULL
);
470 kfree(pdev
->dev
.dma_mask
);
473 platform_device_put(pdev
);
479 EXPORT_SYMBOL_GPL(platform_device_register_full
);
481 static int platform_drv_probe(struct device
*_dev
)
483 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
484 struct platform_device
*dev
= to_platform_device(_dev
);
487 if (ACPI_HANDLE(_dev
))
488 acpi_dev_pm_attach(_dev
, true);
490 ret
= drv
->probe(dev
);
491 if (ret
&& ACPI_HANDLE(_dev
))
492 acpi_dev_pm_detach(_dev
, true);
497 static int platform_drv_probe_fail(struct device
*_dev
)
502 static int platform_drv_remove(struct device
*_dev
)
504 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
505 struct platform_device
*dev
= to_platform_device(_dev
);
508 ret
= drv
->remove(dev
);
509 if (ACPI_HANDLE(_dev
))
510 acpi_dev_pm_detach(_dev
, true);
515 static void platform_drv_shutdown(struct device
*_dev
)
517 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
518 struct platform_device
*dev
= to_platform_device(_dev
);
521 if (ACPI_HANDLE(_dev
))
522 acpi_dev_pm_detach(_dev
, true);
526 * platform_driver_register - register a driver for platform-level devices
527 * @drv: platform driver structure
529 int platform_driver_register(struct platform_driver
*drv
)
531 drv
->driver
.bus
= &platform_bus_type
;
533 drv
->driver
.probe
= platform_drv_probe
;
535 drv
->driver
.remove
= platform_drv_remove
;
537 drv
->driver
.shutdown
= platform_drv_shutdown
;
539 return driver_register(&drv
->driver
);
541 EXPORT_SYMBOL_GPL(platform_driver_register
);
544 * platform_driver_unregister - unregister a driver for platform-level devices
545 * @drv: platform driver structure
547 void platform_driver_unregister(struct platform_driver
*drv
)
549 driver_unregister(&drv
->driver
);
551 EXPORT_SYMBOL_GPL(platform_driver_unregister
);
554 * platform_driver_probe - register driver for non-hotpluggable device
555 * @drv: platform driver structure
556 * @probe: the driver probe routine, probably from an __init section,
557 * must not return -EPROBE_DEFER.
559 * Use this instead of platform_driver_register() when you know the device
560 * is not hotpluggable and has already been registered, and you want to
561 * remove its run-once probe() infrastructure from memory after the driver
562 * has bound to the device.
564 * One typical use for this would be with drivers for controllers integrated
565 * into system-on-chip processors, where the controller devices have been
566 * configured as part of board setup.
568 * This is incompatible with deferred probing so probe() must not
569 * return -EPROBE_DEFER.
571 * Returns zero if the driver registered and bound to a device, else returns
572 * a negative error code and with the driver not registered.
574 int __init_or_module
platform_driver_probe(struct platform_driver
*drv
,
575 int (*probe
)(struct platform_device
*))
579 /* make sure driver won't have bind/unbind attributes */
580 drv
->driver
.suppress_bind_attrs
= true;
582 /* temporary section violation during probe() */
584 retval
= code
= platform_driver_register(drv
);
587 * Fixup that section violation, being paranoid about code scanning
588 * the list of drivers in order to probe new devices. Check to see
589 * if the probe was successful, and make sure any forced probes of
592 spin_lock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
594 if (code
== 0 && list_empty(&drv
->driver
.p
->klist_devices
.k_list
))
596 drv
->driver
.probe
= platform_drv_probe_fail
;
597 spin_unlock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
600 platform_driver_unregister(drv
);
603 EXPORT_SYMBOL_GPL(platform_driver_probe
);
606 * platform_create_bundle - register driver and create corresponding device
607 * @driver: platform driver structure
608 * @probe: the driver probe routine, probably from an __init section
609 * @res: set of resources that needs to be allocated for the device
610 * @n_res: number of resources
611 * @data: platform specific data for this platform device
612 * @size: size of platform specific data
614 * Use this in legacy-style modules that probe hardware directly and
615 * register a single platform device and corresponding platform driver.
617 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
619 struct platform_device
* __init_or_module
platform_create_bundle(
620 struct platform_driver
*driver
,
621 int (*probe
)(struct platform_device
*),
622 struct resource
*res
, unsigned int n_res
,
623 const void *data
, size_t size
)
625 struct platform_device
*pdev
;
628 pdev
= platform_device_alloc(driver
->driver
.name
, -1);
634 error
= platform_device_add_resources(pdev
, res
, n_res
);
638 error
= platform_device_add_data(pdev
, data
, size
);
642 error
= platform_device_add(pdev
);
646 error
= platform_driver_probe(driver
, probe
);
653 platform_device_del(pdev
);
655 platform_device_put(pdev
);
657 return ERR_PTR(error
);
659 EXPORT_SYMBOL_GPL(platform_create_bundle
);
661 /* modalias support enables more hands-off userspace setup:
662 * (a) environment variable lets new-style hotplug events work once system is
663 * fully running: "modprobe $MODALIAS"
664 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
665 * mishandled before system is fully running: "modprobe $(cat modalias)"
667 static ssize_t
modalias_show(struct device
*dev
, struct device_attribute
*a
,
670 struct platform_device
*pdev
= to_platform_device(dev
);
671 int len
= snprintf(buf
, PAGE_SIZE
, "platform:%s\n", pdev
->name
);
673 return (len
>= PAGE_SIZE
) ? (PAGE_SIZE
- 1) : len
;
676 static struct device_attribute platform_dev_attrs
[] = {
681 static int platform_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
683 struct platform_device
*pdev
= to_platform_device(dev
);
686 /* Some devices have extra OF data and an OF-style MODALIAS */
687 rc
= of_device_uevent_modalias(dev
, env
);
691 add_uevent_var(env
, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX
,
696 static const struct platform_device_id
*platform_match_id(
697 const struct platform_device_id
*id
,
698 struct platform_device
*pdev
)
700 while (id
->name
[0]) {
701 if (strcmp(pdev
->name
, id
->name
) == 0) {
711 * platform_match - bind platform device to platform driver.
715 * Platform device IDs are assumed to be encoded like this:
716 * "<name><instance>", where <name> is a short description of the type of
717 * device, like "pci" or "floppy", and <instance> is the enumerated
718 * instance of the device, like '0' or '42'. Driver IDs are simply
719 * "<name>". So, extract the <name> from the platform_device structure,
720 * and compare it against the name of the driver. Return whether they match
723 static int platform_match(struct device
*dev
, struct device_driver
*drv
)
725 struct platform_device
*pdev
= to_platform_device(dev
);
726 struct platform_driver
*pdrv
= to_platform_driver(drv
);
728 /* Attempt an OF style match first */
729 if (of_driver_match_device(dev
, drv
))
732 /* Then try ACPI style match */
733 if (acpi_driver_match_device(dev
, drv
))
736 /* Then try to match against the id table */
738 return platform_match_id(pdrv
->id_table
, pdev
) != NULL
;
740 /* fall-back to driver name match */
741 return (strcmp(pdev
->name
, drv
->name
) == 0);
744 #ifdef CONFIG_PM_SLEEP
746 static int platform_legacy_suspend(struct device
*dev
, pm_message_t mesg
)
748 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
749 struct platform_device
*pdev
= to_platform_device(dev
);
752 if (dev
->driver
&& pdrv
->suspend
)
753 ret
= pdrv
->suspend(pdev
, mesg
);
758 static int platform_legacy_resume(struct device
*dev
)
760 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
761 struct platform_device
*pdev
= to_platform_device(dev
);
764 if (dev
->driver
&& pdrv
->resume
)
765 ret
= pdrv
->resume(pdev
);
770 #endif /* CONFIG_PM_SLEEP */
772 #ifdef CONFIG_SUSPEND
774 int platform_pm_suspend(struct device
*dev
)
776 struct device_driver
*drv
= dev
->driver
;
783 if (drv
->pm
->suspend
)
784 ret
= drv
->pm
->suspend(dev
);
786 ret
= platform_legacy_suspend(dev
, PMSG_SUSPEND
);
792 int platform_pm_resume(struct device
*dev
)
794 struct device_driver
*drv
= dev
->driver
;
802 ret
= drv
->pm
->resume(dev
);
804 ret
= platform_legacy_resume(dev
);
810 #endif /* CONFIG_SUSPEND */
812 #ifdef CONFIG_HIBERNATE_CALLBACKS
814 int platform_pm_freeze(struct device
*dev
)
816 struct device_driver
*drv
= dev
->driver
;
824 ret
= drv
->pm
->freeze(dev
);
826 ret
= platform_legacy_suspend(dev
, PMSG_FREEZE
);
832 int platform_pm_thaw(struct device
*dev
)
834 struct device_driver
*drv
= dev
->driver
;
842 ret
= drv
->pm
->thaw(dev
);
844 ret
= platform_legacy_resume(dev
);
850 int platform_pm_poweroff(struct device
*dev
)
852 struct device_driver
*drv
= dev
->driver
;
859 if (drv
->pm
->poweroff
)
860 ret
= drv
->pm
->poweroff(dev
);
862 ret
= platform_legacy_suspend(dev
, PMSG_HIBERNATE
);
868 int platform_pm_restore(struct device
*dev
)
870 struct device_driver
*drv
= dev
->driver
;
877 if (drv
->pm
->restore
)
878 ret
= drv
->pm
->restore(dev
);
880 ret
= platform_legacy_resume(dev
);
886 #endif /* CONFIG_HIBERNATE_CALLBACKS */
888 static const struct dev_pm_ops platform_dev_pm_ops
= {
889 .runtime_suspend
= pm_generic_runtime_suspend
,
890 .runtime_resume
= pm_generic_runtime_resume
,
891 .runtime_idle
= pm_generic_runtime_idle
,
892 USE_PLATFORM_PM_SLEEP_OPS
895 struct bus_type platform_bus_type
= {
897 .dev_attrs
= platform_dev_attrs
,
898 .match
= platform_match
,
899 .uevent
= platform_uevent
,
900 .pm
= &platform_dev_pm_ops
,
902 EXPORT_SYMBOL_GPL(platform_bus_type
);
904 int __init
platform_bus_init(void)
908 early_platform_cleanup();
910 error
= device_register(&platform_bus
);
913 error
= bus_register(&platform_bus_type
);
915 device_unregister(&platform_bus
);
919 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
920 u64
dma_get_required_mask(struct device
*dev
)
922 u32 low_totalram
= ((max_pfn
- 1) << PAGE_SHIFT
);
923 u32 high_totalram
= ((max_pfn
- 1) >> (32 - PAGE_SHIFT
));
926 if (!high_totalram
) {
927 /* convert to mask just covering totalram */
928 low_totalram
= (1 << (fls(low_totalram
) - 1));
929 low_totalram
+= low_totalram
- 1;
932 high_totalram
= (1 << (fls(high_totalram
) - 1));
933 high_totalram
+= high_totalram
- 1;
934 mask
= (((u64
)high_totalram
) << 32) + 0xffffffff;
938 EXPORT_SYMBOL_GPL(dma_get_required_mask
);
941 static __initdata
LIST_HEAD(early_platform_driver_list
);
942 static __initdata
LIST_HEAD(early_platform_device_list
);
945 * early_platform_driver_register - register early platform driver
946 * @epdrv: early_platform driver structure
947 * @buf: string passed from early_param()
949 * Helper function for early_platform_init() / early_platform_init_buffer()
951 int __init
early_platform_driver_register(struct early_platform_driver
*epdrv
,
957 /* Simply add the driver to the end of the global list.
958 * Drivers will by default be put on the list in compiled-in order.
960 if (!epdrv
->list
.next
) {
961 INIT_LIST_HEAD(&epdrv
->list
);
962 list_add_tail(&epdrv
->list
, &early_platform_driver_list
);
965 /* If the user has specified device then make sure the driver
966 * gets prioritized. The driver of the last device specified on
967 * command line will be put first on the list.
969 n
= strlen(epdrv
->pdrv
->driver
.name
);
970 if (buf
&& !strncmp(buf
, epdrv
->pdrv
->driver
.name
, n
)) {
971 list_move(&epdrv
->list
, &early_platform_driver_list
);
973 /* Allow passing parameters after device name */
974 if (buf
[n
] == '\0' || buf
[n
] == ',')
975 epdrv
->requested_id
= -1;
977 epdrv
->requested_id
= simple_strtoul(&buf
[n
+ 1],
980 if (buf
[n
] != '.' || (tmp
== &buf
[n
+ 1])) {
981 epdrv
->requested_id
= EARLY_PLATFORM_ID_ERROR
;
984 n
+= strcspn(&buf
[n
+ 1], ",") + 1;
990 if (epdrv
->bufsize
) {
991 memcpy(epdrv
->buffer
, &buf
[n
],
992 min_t(int, epdrv
->bufsize
, strlen(&buf
[n
]) + 1));
993 epdrv
->buffer
[epdrv
->bufsize
- 1] = '\0';
1001 * early_platform_add_devices - adds a number of early platform devices
1002 * @devs: array of early platform devices to add
1003 * @num: number of early platform devices in array
1005 * Used by early architecture code to register early platform devices and
1006 * their platform data.
1008 void __init
early_platform_add_devices(struct platform_device
**devs
, int num
)
1013 /* simply add the devices to list */
1014 for (i
= 0; i
< num
; i
++) {
1015 dev
= &devs
[i
]->dev
;
1017 if (!dev
->devres_head
.next
) {
1018 pm_runtime_early_init(dev
);
1019 INIT_LIST_HEAD(&dev
->devres_head
);
1020 list_add_tail(&dev
->devres_head
,
1021 &early_platform_device_list
);
1027 * early_platform_driver_register_all - register early platform drivers
1028 * @class_str: string to identify early platform driver class
1030 * Used by architecture code to register all early platform drivers
1031 * for a certain class. If omitted then only early platform drivers
1032 * with matching kernel command line class parameters will be registered.
1034 void __init
early_platform_driver_register_all(char *class_str
)
1036 /* The "class_str" parameter may or may not be present on the kernel
1037 * command line. If it is present then there may be more than one
1038 * matching parameter.
1040 * Since we register our early platform drivers using early_param()
1041 * we need to make sure that they also get registered in the case
1042 * when the parameter is missing from the kernel command line.
1044 * We use parse_early_options() to make sure the early_param() gets
1045 * called at least once. The early_param() may be called more than
1046 * once since the name of the preferred device may be specified on
1047 * the kernel command line. early_platform_driver_register() handles
1050 parse_early_options(class_str
);
1054 * early_platform_match - find early platform device matching driver
1055 * @epdrv: early platform driver structure
1056 * @id: id to match against
1058 static __init
struct platform_device
*
1059 early_platform_match(struct early_platform_driver
*epdrv
, int id
)
1061 struct platform_device
*pd
;
1063 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1064 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1072 * early_platform_left - check if early platform driver has matching devices
1073 * @epdrv: early platform driver structure
1074 * @id: return true if id or above exists
1076 static __init
int early_platform_left(struct early_platform_driver
*epdrv
,
1079 struct platform_device
*pd
;
1081 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1082 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1090 * early_platform_driver_probe_id - probe drivers matching class_str and id
1091 * @class_str: string to identify early platform driver class
1092 * @id: id to match against
1093 * @nr_probe: number of platform devices to successfully probe before exiting
1095 static int __init
early_platform_driver_probe_id(char *class_str
,
1099 struct early_platform_driver
*epdrv
;
1100 struct platform_device
*match
;
1105 list_for_each_entry(epdrv
, &early_platform_driver_list
, list
) {
1106 /* only use drivers matching our class_str */
1107 if (strcmp(class_str
, epdrv
->class_str
))
1111 match_id
= epdrv
->requested_id
;
1116 left
+= early_platform_left(epdrv
, id
);
1118 /* skip requested id */
1119 switch (epdrv
->requested_id
) {
1120 case EARLY_PLATFORM_ID_ERROR
:
1121 case EARLY_PLATFORM_ID_UNSET
:
1124 if (epdrv
->requested_id
== id
)
1125 match_id
= EARLY_PLATFORM_ID_UNSET
;
1130 case EARLY_PLATFORM_ID_ERROR
:
1131 pr_warn("%s: unable to parse %s parameter\n",
1132 class_str
, epdrv
->pdrv
->driver
.name
);
1134 case EARLY_PLATFORM_ID_UNSET
:
1138 match
= early_platform_match(epdrv
, match_id
);
1143 * Set up a sensible init_name to enable
1144 * dev_name() and others to be used before the
1145 * rest of the driver core is initialized.
1147 if (!match
->dev
.init_name
&& slab_is_available()) {
1148 if (match
->id
!= -1)
1149 match
->dev
.init_name
=
1150 kasprintf(GFP_KERNEL
, "%s.%d",
1154 match
->dev
.init_name
=
1155 kasprintf(GFP_KERNEL
, "%s",
1158 if (!match
->dev
.init_name
)
1162 if (epdrv
->pdrv
->probe(match
))
1163 pr_warn("%s: unable to probe %s early.\n",
1164 class_str
, match
->name
);
1180 * early_platform_driver_probe - probe a class of registered drivers
1181 * @class_str: string to identify early platform driver class
1182 * @nr_probe: number of platform devices to successfully probe before exiting
1183 * @user_only: only probe user specified early platform devices
1185 * Used by architecture code to probe registered early platform drivers
1186 * within a certain class. For probe to happen a registered early platform
1187 * device matching a registered early platform driver is needed.
1189 int __init
early_platform_driver_probe(char *class_str
,
1196 for (i
= -2; n
< nr_probe
; i
++) {
1197 k
= early_platform_driver_probe_id(class_str
, i
, nr_probe
- n
);
1212 * early_platform_cleanup - clean up early platform code
1214 void __init
early_platform_cleanup(void)
1216 struct platform_device
*pd
, *pd2
;
1218 /* clean up the devres list used to chain devices */
1219 list_for_each_entry_safe(pd
, pd2
, &early_platform_device_list
,
1221 list_del(&pd
->dev
.devres_head
);
1222 memset(&pd
->dev
.devres_head
, 0, sizeof(pd
->dev
.devres_head
));