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 struct device platform_bus
= {
33 .init_name
= "platform",
35 EXPORT_SYMBOL_GPL(platform_bus
);
38 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
39 * @pdev: platform device
41 * This is called before platform_device_add() such that any pdev_archdata may
42 * be setup before the platform_notifier is called. So if a user needs to
43 * manipulate any relevant information in the pdev_archdata they can do:
45 * platform_device_alloc()
47 * platform_device_add()
49 * And if they don't care they can just call platform_device_register() and
50 * everything will just work out.
52 void __weak
arch_setup_pdev_archdata(struct platform_device
*pdev
)
57 * platform_get_resource - get a resource for a device
58 * @dev: platform device
59 * @type: resource type
60 * @num: resource index
62 struct resource
*platform_get_resource(struct platform_device
*dev
,
63 unsigned int type
, unsigned int num
)
67 for (i
= 0; i
< dev
->num_resources
; i
++) {
68 struct resource
*r
= &dev
->resource
[i
];
70 if (type
== resource_type(r
) && num
-- == 0)
75 EXPORT_SYMBOL_GPL(platform_get_resource
);
78 * platform_get_irq - get an IRQ for a device
79 * @dev: platform device
80 * @num: IRQ number index
82 int platform_get_irq(struct platform_device
*dev
, unsigned int num
)
85 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
86 if (!dev
|| num
>= dev
->archdata
.num_irqs
)
88 return dev
->archdata
.irqs
[num
];
90 struct resource
*r
= platform_get_resource(dev
, IORESOURCE_IRQ
, num
);
92 return r
? r
->start
: -ENXIO
;
95 EXPORT_SYMBOL_GPL(platform_get_irq
);
98 * platform_get_resource_byname - get a resource for a device by name
99 * @dev: platform device
100 * @type: resource type
101 * @name: resource name
103 struct resource
*platform_get_resource_byname(struct platform_device
*dev
,
109 for (i
= 0; i
< dev
->num_resources
; i
++) {
110 struct resource
*r
= &dev
->resource
[i
];
112 if (unlikely(!r
->name
))
115 if (type
== resource_type(r
) && !strcmp(r
->name
, name
))
120 EXPORT_SYMBOL_GPL(platform_get_resource_byname
);
123 * platform_get_irq_byname - get an IRQ for a device by name
124 * @dev: platform device
127 int platform_get_irq_byname(struct platform_device
*dev
, const char *name
)
129 struct resource
*r
= platform_get_resource_byname(dev
, IORESOURCE_IRQ
,
132 return r
? r
->start
: -ENXIO
;
134 EXPORT_SYMBOL_GPL(platform_get_irq_byname
);
137 * platform_add_devices - add a numbers of platform devices
138 * @devs: array of platform devices to add
139 * @num: number of platform devices in array
141 int platform_add_devices(struct platform_device
**devs
, int num
)
145 for (i
= 0; i
< num
; i
++) {
146 ret
= platform_device_register(devs
[i
]);
149 platform_device_unregister(devs
[i
]);
156 EXPORT_SYMBOL_GPL(platform_add_devices
);
158 struct platform_object
{
159 struct platform_device pdev
;
164 * platform_device_put - destroy a platform device
165 * @pdev: platform device to free
167 * Free all memory associated with a platform device. This function must
168 * _only_ be externally called in error cases. All other usage is a bug.
170 void platform_device_put(struct platform_device
*pdev
)
173 put_device(&pdev
->dev
);
175 EXPORT_SYMBOL_GPL(platform_device_put
);
177 static void platform_device_release(struct device
*dev
)
179 struct platform_object
*pa
= container_of(dev
, struct platform_object
,
182 of_device_node_put(&pa
->pdev
.dev
);
183 kfree(pa
->pdev
.dev
.platform_data
);
184 kfree(pa
->pdev
.mfd_cell
);
185 kfree(pa
->pdev
.resource
);
190 * platform_device_alloc - create a platform device
191 * @name: base name of the device we're adding
194 * Create a platform device object which can have other objects attached
195 * to it, and which will have attached objects freed when it is released.
197 struct platform_device
*platform_device_alloc(const char *name
, int id
)
199 struct platform_object
*pa
;
201 pa
= kzalloc(sizeof(struct platform_object
) + strlen(name
), GFP_KERNEL
);
203 strcpy(pa
->name
, name
);
204 pa
->pdev
.name
= pa
->name
;
206 device_initialize(&pa
->pdev
.dev
);
207 pa
->pdev
.dev
.release
= platform_device_release
;
208 arch_setup_pdev_archdata(&pa
->pdev
);
211 return pa
? &pa
->pdev
: NULL
;
213 EXPORT_SYMBOL_GPL(platform_device_alloc
);
216 * platform_device_add_resources - add resources to a platform device
217 * @pdev: platform device allocated by platform_device_alloc to add resources to
218 * @res: set of resources that needs to be allocated for the device
219 * @num: number of resources
221 * Add a copy of the resources to the platform device. The memory
222 * associated with the resources will be freed when the platform device is
225 int platform_device_add_resources(struct platform_device
*pdev
,
226 const struct resource
*res
, unsigned int num
)
228 struct resource
*r
= NULL
;
231 r
= kmemdup(res
, sizeof(struct resource
) * num
, GFP_KERNEL
);
236 kfree(pdev
->resource
);
238 pdev
->num_resources
= num
;
241 EXPORT_SYMBOL_GPL(platform_device_add_resources
);
244 * platform_device_add_data - add platform-specific data to a platform device
245 * @pdev: platform device allocated by platform_device_alloc to add resources to
246 * @data: platform specific data for this platform device
247 * @size: size of platform specific data
249 * Add a copy of platform specific data to the platform device's
250 * platform_data pointer. The memory associated with the platform data
251 * will be freed when the platform device is released.
253 int platform_device_add_data(struct platform_device
*pdev
, const void *data
,
259 d
= kmemdup(data
, size
, GFP_KERNEL
);
264 kfree(pdev
->dev
.platform_data
);
265 pdev
->dev
.platform_data
= d
;
268 EXPORT_SYMBOL_GPL(platform_device_add_data
);
271 * platform_device_add - add a platform device to device hierarchy
272 * @pdev: platform device we're adding
274 * This is part 2 of platform_device_register(), though may be called
275 * separately _iff_ pdev was allocated by platform_device_alloc().
277 int platform_device_add(struct platform_device
*pdev
)
284 if (!pdev
->dev
.parent
)
285 pdev
->dev
.parent
= &platform_bus
;
287 pdev
->dev
.bus
= &platform_bus_type
;
291 dev_set_name(&pdev
->dev
, "%s.%d", pdev
->name
, pdev
->id
);
293 case PLATFORM_DEVID_NONE
:
294 dev_set_name(&pdev
->dev
, "%s", pdev
->name
);
296 case PLATFORM_DEVID_AUTO
:
298 * Automatically allocated device ID. We mark it as such so
299 * that we remember it must be freed, and we append a suffix
300 * to avoid namespace collision with explicit IDs.
302 ret
= ida_simple_get(&platform_devid_ida
, 0, 0, GFP_KERNEL
);
306 pdev
->id_auto
= true;
307 dev_set_name(&pdev
->dev
, "%s.%d.auto", pdev
->name
, pdev
->id
);
311 for (i
= 0; i
< pdev
->num_resources
; i
++) {
312 struct resource
*p
, *r
= &pdev
->resource
[i
];
315 r
->name
= dev_name(&pdev
->dev
);
319 if (resource_type(r
) == IORESOURCE_MEM
)
321 else if (resource_type(r
) == IORESOURCE_IO
)
322 p
= &ioport_resource
;
325 if (p
&& insert_resource(p
, r
)) {
326 dev_err(&pdev
->dev
, "failed to claim resource %d\n", i
);
332 pr_debug("Registering platform device '%s'. Parent at %s\n",
333 dev_name(&pdev
->dev
), dev_name(pdev
->dev
.parent
));
335 ret
= device_add(&pdev
->dev
);
341 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
342 pdev
->id
= PLATFORM_DEVID_AUTO
;
346 struct resource
*r
= &pdev
->resource
[i
];
347 unsigned long type
= resource_type(r
);
349 if (type
== IORESOURCE_MEM
|| type
== IORESOURCE_IO
)
356 EXPORT_SYMBOL_GPL(platform_device_add
);
359 * platform_device_del - remove a platform-level device
360 * @pdev: platform device we're removing
362 * Note that this function will also release all memory- and port-based
363 * resources owned by the device (@dev->resource). This function must
364 * _only_ be externally called in error cases. All other usage is a bug.
366 void platform_device_del(struct platform_device
*pdev
)
371 device_del(&pdev
->dev
);
374 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
375 pdev
->id
= PLATFORM_DEVID_AUTO
;
378 for (i
= 0; i
< pdev
->num_resources
; i
++) {
379 struct resource
*r
= &pdev
->resource
[i
];
380 unsigned long type
= resource_type(r
);
382 if (type
== IORESOURCE_MEM
|| type
== IORESOURCE_IO
)
387 EXPORT_SYMBOL_GPL(platform_device_del
);
390 * platform_device_register - add a platform-level device
391 * @pdev: platform device we're adding
393 int platform_device_register(struct platform_device
*pdev
)
395 device_initialize(&pdev
->dev
);
396 arch_setup_pdev_archdata(pdev
);
397 return platform_device_add(pdev
);
399 EXPORT_SYMBOL_GPL(platform_device_register
);
402 * platform_device_unregister - unregister a platform-level device
403 * @pdev: platform device we're unregistering
405 * Unregistration is done in 2 steps. First we release all resources
406 * and remove it from the subsystem, then we drop reference count by
407 * calling platform_device_put().
409 void platform_device_unregister(struct platform_device
*pdev
)
411 platform_device_del(pdev
);
412 platform_device_put(pdev
);
414 EXPORT_SYMBOL_GPL(platform_device_unregister
);
417 * platform_device_register_full - add a platform-level device with
418 * resources and platform-specific data
420 * @pdevinfo: data used to create device
422 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
424 struct platform_device
*platform_device_register_full(
425 const struct platform_device_info
*pdevinfo
)
428 struct platform_device
*pdev
;
430 pdev
= platform_device_alloc(pdevinfo
->name
, pdevinfo
->id
);
434 pdev
->dev
.parent
= pdevinfo
->parent
;
435 ACPI_HANDLE_SET(&pdev
->dev
, pdevinfo
->acpi_node
.handle
);
437 if (pdevinfo
->dma_mask
) {
439 * This memory isn't freed when the device is put,
440 * I don't have a nice idea for that though. Conceptually
441 * dma_mask in struct device should not be a pointer.
442 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
445 kmalloc(sizeof(*pdev
->dev
.dma_mask
), GFP_KERNEL
);
446 if (!pdev
->dev
.dma_mask
)
449 *pdev
->dev
.dma_mask
= pdevinfo
->dma_mask
;
450 pdev
->dev
.coherent_dma_mask
= pdevinfo
->dma_mask
;
453 ret
= platform_device_add_resources(pdev
,
454 pdevinfo
->res
, pdevinfo
->num_res
);
458 ret
= platform_device_add_data(pdev
,
459 pdevinfo
->data
, pdevinfo
->size_data
);
463 ret
= platform_device_add(pdev
);
466 ACPI_HANDLE_SET(&pdev
->dev
, NULL
);
467 kfree(pdev
->dev
.dma_mask
);
470 platform_device_put(pdev
);
476 EXPORT_SYMBOL_GPL(platform_device_register_full
);
478 static int platform_drv_probe(struct device
*_dev
)
480 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
481 struct platform_device
*dev
= to_platform_device(_dev
);
484 if (ACPI_HANDLE(_dev
))
485 acpi_dev_pm_attach(_dev
, true);
487 ret
= drv
->probe(dev
);
488 if (ret
&& ACPI_HANDLE(_dev
))
489 acpi_dev_pm_detach(_dev
, true);
494 static int platform_drv_probe_fail(struct device
*_dev
)
499 static int platform_drv_remove(struct device
*_dev
)
501 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
502 struct platform_device
*dev
= to_platform_device(_dev
);
505 ret
= drv
->remove(dev
);
506 if (ACPI_HANDLE(_dev
))
507 acpi_dev_pm_detach(_dev
, true);
512 static void platform_drv_shutdown(struct device
*_dev
)
514 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
515 struct platform_device
*dev
= to_platform_device(_dev
);
518 if (ACPI_HANDLE(_dev
))
519 acpi_dev_pm_detach(_dev
, true);
523 * __platform_driver_register - register a driver for platform-level devices
524 * @drv: platform driver structure
526 int __platform_driver_register(struct platform_driver
*drv
,
527 struct module
*owner
)
529 drv
->driver
.owner
= owner
;
530 drv
->driver
.bus
= &platform_bus_type
;
532 drv
->driver
.probe
= platform_drv_probe
;
534 drv
->driver
.remove
= platform_drv_remove
;
536 drv
->driver
.shutdown
= platform_drv_shutdown
;
538 return driver_register(&drv
->driver
);
540 EXPORT_SYMBOL_GPL(__platform_driver_register
);
543 * platform_driver_unregister - unregister a driver for platform-level devices
544 * @drv: platform driver structure
546 void platform_driver_unregister(struct platform_driver
*drv
)
548 driver_unregister(&drv
->driver
);
550 EXPORT_SYMBOL_GPL(platform_driver_unregister
);
553 * platform_driver_probe - register driver for non-hotpluggable device
554 * @drv: platform driver structure
555 * @probe: the driver probe routine, probably from an __init section,
556 * must not return -EPROBE_DEFER.
558 * Use this instead of platform_driver_register() when you know the device
559 * is not hotpluggable and has already been registered, and you want to
560 * remove its run-once probe() infrastructure from memory after the driver
561 * has bound to the device.
563 * One typical use for this would be with drivers for controllers integrated
564 * into system-on-chip processors, where the controller devices have been
565 * configured as part of board setup.
567 * This is incompatible with deferred probing so probe() must not
568 * return -EPROBE_DEFER.
570 * Returns zero if the driver registered and bound to a device, else returns
571 * a negative error code and with the driver not registered.
573 int __init_or_module
platform_driver_probe(struct platform_driver
*drv
,
574 int (*probe
)(struct platform_device
*))
578 /* make sure driver won't have bind/unbind attributes */
579 drv
->driver
.suppress_bind_attrs
= true;
581 /* temporary section violation during probe() */
583 retval
= code
= platform_driver_register(drv
);
586 * Fixup that section violation, being paranoid about code scanning
587 * the list of drivers in order to probe new devices. Check to see
588 * if the probe was successful, and make sure any forced probes of
591 spin_lock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
593 if (code
== 0 && list_empty(&drv
->driver
.p
->klist_devices
.k_list
))
595 drv
->driver
.probe
= platform_drv_probe_fail
;
596 spin_unlock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
599 platform_driver_unregister(drv
);
602 EXPORT_SYMBOL_GPL(platform_driver_probe
);
605 * platform_create_bundle - register driver and create corresponding device
606 * @driver: platform driver structure
607 * @probe: the driver probe routine, probably from an __init section
608 * @res: set of resources that needs to be allocated for the device
609 * @n_res: number of resources
610 * @data: platform specific data for this platform device
611 * @size: size of platform specific data
613 * Use this in legacy-style modules that probe hardware directly and
614 * register a single platform device and corresponding platform driver.
616 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
618 struct platform_device
* __init_or_module
platform_create_bundle(
619 struct platform_driver
*driver
,
620 int (*probe
)(struct platform_device
*),
621 struct resource
*res
, unsigned int n_res
,
622 const void *data
, size_t size
)
624 struct platform_device
*pdev
;
627 pdev
= platform_device_alloc(driver
->driver
.name
, -1);
633 error
= platform_device_add_resources(pdev
, res
, n_res
);
637 error
= platform_device_add_data(pdev
, data
, size
);
641 error
= platform_device_add(pdev
);
645 error
= platform_driver_probe(driver
, probe
);
652 platform_device_del(pdev
);
654 platform_device_put(pdev
);
656 return ERR_PTR(error
);
658 EXPORT_SYMBOL_GPL(platform_create_bundle
);
660 /* modalias support enables more hands-off userspace setup:
661 * (a) environment variable lets new-style hotplug events work once system is
662 * fully running: "modprobe $MODALIAS"
663 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
664 * mishandled before system is fully running: "modprobe $(cat modalias)"
666 static ssize_t
modalias_show(struct device
*dev
, struct device_attribute
*a
,
669 struct platform_device
*pdev
= to_platform_device(dev
);
670 int len
= snprintf(buf
, PAGE_SIZE
, "platform:%s\n", pdev
->name
);
672 return (len
>= PAGE_SIZE
) ? (PAGE_SIZE
- 1) : len
;
675 static struct device_attribute platform_dev_attrs
[] = {
680 static int platform_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
682 struct platform_device
*pdev
= to_platform_device(dev
);
685 /* Some devices have extra OF data and an OF-style MODALIAS */
686 rc
= of_device_uevent_modalias(dev
, env
);
690 add_uevent_var(env
, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX
,
695 static const struct platform_device_id
*platform_match_id(
696 const struct platform_device_id
*id
,
697 struct platform_device
*pdev
)
699 while (id
->name
[0]) {
700 if (strcmp(pdev
->name
, id
->name
) == 0) {
710 * platform_match - bind platform device to platform driver.
714 * Platform device IDs are assumed to be encoded like this:
715 * "<name><instance>", where <name> is a short description of the type of
716 * device, like "pci" or "floppy", and <instance> is the enumerated
717 * instance of the device, like '0' or '42'. Driver IDs are simply
718 * "<name>". So, extract the <name> from the platform_device structure,
719 * and compare it against the name of the driver. Return whether they match
722 static int platform_match(struct device
*dev
, struct device_driver
*drv
)
724 struct platform_device
*pdev
= to_platform_device(dev
);
725 struct platform_driver
*pdrv
= to_platform_driver(drv
);
727 /* Attempt an OF style match first */
728 if (of_driver_match_device(dev
, drv
))
731 /* Then try ACPI style match */
732 if (acpi_driver_match_device(dev
, drv
))
735 /* Then try to match against the id table */
737 return platform_match_id(pdrv
->id_table
, pdev
) != NULL
;
739 /* fall-back to driver name match */
740 return (strcmp(pdev
->name
, drv
->name
) == 0);
743 #ifdef CONFIG_PM_SLEEP
745 static int platform_legacy_suspend(struct device
*dev
, pm_message_t mesg
)
747 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
748 struct platform_device
*pdev
= to_platform_device(dev
);
751 if (dev
->driver
&& pdrv
->suspend
)
752 ret
= pdrv
->suspend(pdev
, mesg
);
757 static int platform_legacy_resume(struct device
*dev
)
759 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
760 struct platform_device
*pdev
= to_platform_device(dev
);
763 if (dev
->driver
&& pdrv
->resume
)
764 ret
= pdrv
->resume(pdev
);
769 #endif /* CONFIG_PM_SLEEP */
771 #ifdef CONFIG_SUSPEND
773 int platform_pm_suspend(struct device
*dev
)
775 struct device_driver
*drv
= dev
->driver
;
782 if (drv
->pm
->suspend
)
783 ret
= drv
->pm
->suspend(dev
);
785 ret
= platform_legacy_suspend(dev
, PMSG_SUSPEND
);
791 int platform_pm_resume(struct device
*dev
)
793 struct device_driver
*drv
= dev
->driver
;
801 ret
= drv
->pm
->resume(dev
);
803 ret
= platform_legacy_resume(dev
);
809 #endif /* CONFIG_SUSPEND */
811 #ifdef CONFIG_HIBERNATE_CALLBACKS
813 int platform_pm_freeze(struct device
*dev
)
815 struct device_driver
*drv
= dev
->driver
;
823 ret
= drv
->pm
->freeze(dev
);
825 ret
= platform_legacy_suspend(dev
, PMSG_FREEZE
);
831 int platform_pm_thaw(struct device
*dev
)
833 struct device_driver
*drv
= dev
->driver
;
841 ret
= drv
->pm
->thaw(dev
);
843 ret
= platform_legacy_resume(dev
);
849 int platform_pm_poweroff(struct device
*dev
)
851 struct device_driver
*drv
= dev
->driver
;
858 if (drv
->pm
->poweroff
)
859 ret
= drv
->pm
->poweroff(dev
);
861 ret
= platform_legacy_suspend(dev
, PMSG_HIBERNATE
);
867 int platform_pm_restore(struct device
*dev
)
869 struct device_driver
*drv
= dev
->driver
;
876 if (drv
->pm
->restore
)
877 ret
= drv
->pm
->restore(dev
);
879 ret
= platform_legacy_resume(dev
);
885 #endif /* CONFIG_HIBERNATE_CALLBACKS */
887 static const struct dev_pm_ops platform_dev_pm_ops
= {
888 .runtime_suspend
= pm_generic_runtime_suspend
,
889 .runtime_resume
= pm_generic_runtime_resume
,
890 USE_PLATFORM_PM_SLEEP_OPS
893 struct bus_type platform_bus_type
= {
895 .dev_attrs
= platform_dev_attrs
,
896 .match
= platform_match
,
897 .uevent
= platform_uevent
,
898 .pm
= &platform_dev_pm_ops
,
900 EXPORT_SYMBOL_GPL(platform_bus_type
);
902 int __init
platform_bus_init(void)
906 early_platform_cleanup();
908 error
= device_register(&platform_bus
);
911 error
= bus_register(&platform_bus_type
);
913 device_unregister(&platform_bus
);
917 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
918 u64
dma_get_required_mask(struct device
*dev
)
920 u32 low_totalram
= ((max_pfn
- 1) << PAGE_SHIFT
);
921 u32 high_totalram
= ((max_pfn
- 1) >> (32 - PAGE_SHIFT
));
924 if (!high_totalram
) {
925 /* convert to mask just covering totalram */
926 low_totalram
= (1 << (fls(low_totalram
) - 1));
927 low_totalram
+= low_totalram
- 1;
930 high_totalram
= (1 << (fls(high_totalram
) - 1));
931 high_totalram
+= high_totalram
- 1;
932 mask
= (((u64
)high_totalram
) << 32) + 0xffffffff;
936 EXPORT_SYMBOL_GPL(dma_get_required_mask
);
939 static __initdata
LIST_HEAD(early_platform_driver_list
);
940 static __initdata
LIST_HEAD(early_platform_device_list
);
943 * early_platform_driver_register - register early platform driver
944 * @epdrv: early_platform driver structure
945 * @buf: string passed from early_param()
947 * Helper function for early_platform_init() / early_platform_init_buffer()
949 int __init
early_platform_driver_register(struct early_platform_driver
*epdrv
,
955 /* Simply add the driver to the end of the global list.
956 * Drivers will by default be put on the list in compiled-in order.
958 if (!epdrv
->list
.next
) {
959 INIT_LIST_HEAD(&epdrv
->list
);
960 list_add_tail(&epdrv
->list
, &early_platform_driver_list
);
963 /* If the user has specified device then make sure the driver
964 * gets prioritized. The driver of the last device specified on
965 * command line will be put first on the list.
967 n
= strlen(epdrv
->pdrv
->driver
.name
);
968 if (buf
&& !strncmp(buf
, epdrv
->pdrv
->driver
.name
, n
)) {
969 list_move(&epdrv
->list
, &early_platform_driver_list
);
971 /* Allow passing parameters after device name */
972 if (buf
[n
] == '\0' || buf
[n
] == ',')
973 epdrv
->requested_id
= -1;
975 epdrv
->requested_id
= simple_strtoul(&buf
[n
+ 1],
978 if (buf
[n
] != '.' || (tmp
== &buf
[n
+ 1])) {
979 epdrv
->requested_id
= EARLY_PLATFORM_ID_ERROR
;
982 n
+= strcspn(&buf
[n
+ 1], ",") + 1;
988 if (epdrv
->bufsize
) {
989 memcpy(epdrv
->buffer
, &buf
[n
],
990 min_t(int, epdrv
->bufsize
, strlen(&buf
[n
]) + 1));
991 epdrv
->buffer
[epdrv
->bufsize
- 1] = '\0';
999 * early_platform_add_devices - adds a number of early platform devices
1000 * @devs: array of early platform devices to add
1001 * @num: number of early platform devices in array
1003 * Used by early architecture code to register early platform devices and
1004 * their platform data.
1006 void __init
early_platform_add_devices(struct platform_device
**devs
, int num
)
1011 /* simply add the devices to list */
1012 for (i
= 0; i
< num
; i
++) {
1013 dev
= &devs
[i
]->dev
;
1015 if (!dev
->devres_head
.next
) {
1016 pm_runtime_early_init(dev
);
1017 INIT_LIST_HEAD(&dev
->devres_head
);
1018 list_add_tail(&dev
->devres_head
,
1019 &early_platform_device_list
);
1025 * early_platform_driver_register_all - register early platform drivers
1026 * @class_str: string to identify early platform driver class
1028 * Used by architecture code to register all early platform drivers
1029 * for a certain class. If omitted then only early platform drivers
1030 * with matching kernel command line class parameters will be registered.
1032 void __init
early_platform_driver_register_all(char *class_str
)
1034 /* The "class_str" parameter may or may not be present on the kernel
1035 * command line. If it is present then there may be more than one
1036 * matching parameter.
1038 * Since we register our early platform drivers using early_param()
1039 * we need to make sure that they also get registered in the case
1040 * when the parameter is missing from the kernel command line.
1042 * We use parse_early_options() to make sure the early_param() gets
1043 * called at least once. The early_param() may be called more than
1044 * once since the name of the preferred device may be specified on
1045 * the kernel command line. early_platform_driver_register() handles
1048 parse_early_options(class_str
);
1052 * early_platform_match - find early platform device matching driver
1053 * @epdrv: early platform driver structure
1054 * @id: id to match against
1056 static __init
struct platform_device
*
1057 early_platform_match(struct early_platform_driver
*epdrv
, int id
)
1059 struct platform_device
*pd
;
1061 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1062 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1070 * early_platform_left - check if early platform driver has matching devices
1071 * @epdrv: early platform driver structure
1072 * @id: return true if id or above exists
1074 static __init
int early_platform_left(struct early_platform_driver
*epdrv
,
1077 struct platform_device
*pd
;
1079 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1080 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1088 * early_platform_driver_probe_id - probe drivers matching class_str and id
1089 * @class_str: string to identify early platform driver class
1090 * @id: id to match against
1091 * @nr_probe: number of platform devices to successfully probe before exiting
1093 static int __init
early_platform_driver_probe_id(char *class_str
,
1097 struct early_platform_driver
*epdrv
;
1098 struct platform_device
*match
;
1103 list_for_each_entry(epdrv
, &early_platform_driver_list
, list
) {
1104 /* only use drivers matching our class_str */
1105 if (strcmp(class_str
, epdrv
->class_str
))
1109 match_id
= epdrv
->requested_id
;
1114 left
+= early_platform_left(epdrv
, id
);
1116 /* skip requested id */
1117 switch (epdrv
->requested_id
) {
1118 case EARLY_PLATFORM_ID_ERROR
:
1119 case EARLY_PLATFORM_ID_UNSET
:
1122 if (epdrv
->requested_id
== id
)
1123 match_id
= EARLY_PLATFORM_ID_UNSET
;
1128 case EARLY_PLATFORM_ID_ERROR
:
1129 pr_warn("%s: unable to parse %s parameter\n",
1130 class_str
, epdrv
->pdrv
->driver
.name
);
1132 case EARLY_PLATFORM_ID_UNSET
:
1136 match
= early_platform_match(epdrv
, match_id
);
1141 * Set up a sensible init_name to enable
1142 * dev_name() and others to be used before the
1143 * rest of the driver core is initialized.
1145 if (!match
->dev
.init_name
&& slab_is_available()) {
1146 if (match
->id
!= -1)
1147 match
->dev
.init_name
=
1148 kasprintf(GFP_KERNEL
, "%s.%d",
1152 match
->dev
.init_name
=
1153 kasprintf(GFP_KERNEL
, "%s",
1156 if (!match
->dev
.init_name
)
1160 if (epdrv
->pdrv
->probe(match
))
1161 pr_warn("%s: unable to probe %s early.\n",
1162 class_str
, match
->name
);
1178 * early_platform_driver_probe - probe a class of registered drivers
1179 * @class_str: string to identify early platform driver class
1180 * @nr_probe: number of platform devices to successfully probe before exiting
1181 * @user_only: only probe user specified early platform devices
1183 * Used by architecture code to probe registered early platform drivers
1184 * within a certain class. For probe to happen a registered early platform
1185 * device matching a registered early platform driver is needed.
1187 int __init
early_platform_driver_probe(char *class_str
,
1194 for (i
= -2; n
< nr_probe
; i
++) {
1195 k
= early_platform_driver_probe_id(class_str
, i
, nr_probe
- n
);
1210 * early_platform_cleanup - clean up early platform code
1212 void __init
early_platform_cleanup(void)
1214 struct platform_device
*pd
, *pd2
;
1216 /* clean up the devres list used to chain devices */
1217 list_for_each_entry_safe(pd
, pd2
, &early_platform_device_list
,
1219 list_del(&pd
->dev
.devres_head
);
1220 memset(&pd
->dev
.devres_head
, 0, sizeof(pd
->dev
.devres_head
));