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/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>
32 #include "power/power.h"
34 /* For automatically allocated device IDs */
35 static DEFINE_IDA(platform_devid_ida
);
37 struct device platform_bus
= {
38 .init_name
= "platform",
40 EXPORT_SYMBOL_GPL(platform_bus
);
43 * arch_setup_pdev_archdata - Allow manipulation of archdata before its used
44 * @pdev: platform device
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:
50 * platform_device_alloc()
52 * platform_device_add()
54 * And if they don't care they can just call platform_device_register() and
55 * everything will just work out.
57 void __weak
arch_setup_pdev_archdata(struct platform_device
*pdev
)
62 * platform_get_resource - get a resource for a device
63 * @dev: platform device
64 * @type: resource type
65 * @num: resource index
67 struct resource
*platform_get_resource(struct platform_device
*dev
,
68 unsigned int type
, unsigned int num
)
72 for (i
= 0; i
< dev
->num_resources
; i
++) {
73 struct resource
*r
= &dev
->resource
[i
];
75 if (type
== resource_type(r
) && num
-- == 0)
80 EXPORT_SYMBOL_GPL(platform_get_resource
);
83 * platform_get_irq - get an IRQ for a device
84 * @dev: platform device
85 * @num: IRQ number index
87 int platform_get_irq(struct platform_device
*dev
, unsigned int num
)
90 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
91 if (!dev
|| num
>= dev
->archdata
.num_irqs
)
93 return dev
->archdata
.irqs
[num
];
96 if (IS_ENABLED(CONFIG_OF_IRQ
) && dev
->dev
.of_node
) {
99 ret
= of_irq_get(dev
->dev
.of_node
, num
);
100 if (ret
>= 0 || ret
== -EPROBE_DEFER
)
104 r
= platform_get_resource(dev
, IORESOURCE_IRQ
, num
);
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*
111 if (r
&& r
->flags
& IORESOURCE_BITS
)
112 irqd_set_trigger_type(irq_get_irq_data(r
->start
),
113 r
->flags
& IORESOURCE_BITS
);
115 return r
? r
->start
: -ENXIO
;
118 EXPORT_SYMBOL_GPL(platform_get_irq
);
121 * platform_irq_count - Count the number of IRQs a platform device uses
122 * @dev: platform device
124 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
126 int platform_irq_count(struct platform_device
*dev
)
130 while ((ret
= platform_get_irq(dev
, nr
)) >= 0)
133 if (ret
== -EPROBE_DEFER
)
138 EXPORT_SYMBOL_GPL(platform_irq_count
);
141 * platform_get_resource_byname - get a resource for a device by name
142 * @dev: platform device
143 * @type: resource type
144 * @name: resource name
146 struct resource
*platform_get_resource_byname(struct platform_device
*dev
,
152 for (i
= 0; i
< dev
->num_resources
; i
++) {
153 struct resource
*r
= &dev
->resource
[i
];
155 if (unlikely(!r
->name
))
158 if (type
== resource_type(r
) && !strcmp(r
->name
, name
))
163 EXPORT_SYMBOL_GPL(platform_get_resource_byname
);
166 * platform_get_irq_byname - get an IRQ for a device by name
167 * @dev: platform device
170 int platform_get_irq_byname(struct platform_device
*dev
, const char *name
)
174 if (IS_ENABLED(CONFIG_OF_IRQ
) && dev
->dev
.of_node
) {
177 ret
= of_irq_get_byname(dev
->dev
.of_node
, name
);
178 if (ret
>= 0 || ret
== -EPROBE_DEFER
)
182 r
= platform_get_resource_byname(dev
, IORESOURCE_IRQ
, name
);
183 return r
? r
->start
: -ENXIO
;
185 EXPORT_SYMBOL_GPL(platform_get_irq_byname
);
188 * platform_add_devices - add a numbers of platform devices
189 * @devs: array of platform devices to add
190 * @num: number of platform devices in array
192 int platform_add_devices(struct platform_device
**devs
, int num
)
196 for (i
= 0; i
< num
; i
++) {
197 ret
= platform_device_register(devs
[i
]);
200 platform_device_unregister(devs
[i
]);
207 EXPORT_SYMBOL_GPL(platform_add_devices
);
209 struct platform_object
{
210 struct platform_device pdev
;
215 * platform_device_put - destroy a platform device
216 * @pdev: platform device to free
218 * Free all memory associated with a platform device. This function must
219 * _only_ be externally called in error cases. All other usage is a bug.
221 void platform_device_put(struct platform_device
*pdev
)
224 put_device(&pdev
->dev
);
226 EXPORT_SYMBOL_GPL(platform_device_put
);
228 static void platform_device_release(struct device
*dev
)
230 struct platform_object
*pa
= container_of(dev
, struct platform_object
,
233 of_device_node_put(&pa
->pdev
.dev
);
234 kfree(pa
->pdev
.dev
.platform_data
);
235 kfree(pa
->pdev
.mfd_cell
);
236 kfree(pa
->pdev
.resource
);
237 kfree(pa
->pdev
.driver_override
);
242 * platform_device_alloc - create a platform device
243 * @name: base name of the device we're adding
246 * Create a platform device object which can have other objects attached
247 * to it, and which will have attached objects freed when it is released.
249 struct platform_device
*platform_device_alloc(const char *name
, int id
)
251 struct platform_object
*pa
;
253 pa
= kzalloc(sizeof(*pa
) + strlen(name
) + 1, GFP_KERNEL
);
255 strcpy(pa
->name
, name
);
256 pa
->pdev
.name
= pa
->name
;
258 device_initialize(&pa
->pdev
.dev
);
259 pa
->pdev
.dev
.release
= platform_device_release
;
260 arch_setup_pdev_archdata(&pa
->pdev
);
263 return pa
? &pa
->pdev
: NULL
;
265 EXPORT_SYMBOL_GPL(platform_device_alloc
);
268 * platform_device_add_resources - add resources to a platform device
269 * @pdev: platform device allocated by platform_device_alloc to add resources to
270 * @res: set of resources that needs to be allocated for the device
271 * @num: number of resources
273 * Add a copy of the resources to the platform device. The memory
274 * associated with the resources will be freed when the platform device is
277 int platform_device_add_resources(struct platform_device
*pdev
,
278 const struct resource
*res
, unsigned int num
)
280 struct resource
*r
= NULL
;
283 r
= kmemdup(res
, sizeof(struct resource
) * num
, GFP_KERNEL
);
288 kfree(pdev
->resource
);
290 pdev
->num_resources
= num
;
293 EXPORT_SYMBOL_GPL(platform_device_add_resources
);
296 * platform_device_add_data - add platform-specific data to a platform device
297 * @pdev: platform device allocated by platform_device_alloc to add resources to
298 * @data: platform specific data for this platform device
299 * @size: size of platform specific data
301 * Add a copy of platform specific data to the platform device's
302 * platform_data pointer. The memory associated with the platform data
303 * will be freed when the platform device is released.
305 int platform_device_add_data(struct platform_device
*pdev
, const void *data
,
311 d
= kmemdup(data
, size
, GFP_KERNEL
);
316 kfree(pdev
->dev
.platform_data
);
317 pdev
->dev
.platform_data
= d
;
320 EXPORT_SYMBOL_GPL(platform_device_add_data
);
323 * platform_device_add_properties - add built-in properties to a platform device
324 * @pdev: platform device to add properties to
325 * @pset: properties to add
327 * The function will take deep copy of the properties in @pset and attach
328 * the copy to the platform device. The memory associated with properties
329 * will be freed when the platform device is released.
331 int platform_device_add_properties(struct platform_device
*pdev
,
332 const struct property_set
*pset
)
334 return device_add_property_set(&pdev
->dev
, pset
);
336 EXPORT_SYMBOL_GPL(platform_device_add_properties
);
339 * platform_device_add - add a platform device to device hierarchy
340 * @pdev: platform device we're adding
342 * This is part 2 of platform_device_register(), though may be called
343 * separately _iff_ pdev was allocated by platform_device_alloc().
345 int platform_device_add(struct platform_device
*pdev
)
352 if (!pdev
->dev
.parent
)
353 pdev
->dev
.parent
= &platform_bus
;
355 pdev
->dev
.bus
= &platform_bus_type
;
359 dev_set_name(&pdev
->dev
, "%s.%d", pdev
->name
, pdev
->id
);
361 case PLATFORM_DEVID_NONE
:
362 dev_set_name(&pdev
->dev
, "%s", pdev
->name
);
364 case PLATFORM_DEVID_AUTO
:
366 * Automatically allocated device ID. We mark it as such so
367 * that we remember it must be freed, and we append a suffix
368 * to avoid namespace collision with explicit IDs.
370 ret
= ida_simple_get(&platform_devid_ida
, 0, 0, GFP_KERNEL
);
374 pdev
->id_auto
= true;
375 dev_set_name(&pdev
->dev
, "%s.%d.auto", pdev
->name
, pdev
->id
);
379 for (i
= 0; i
< pdev
->num_resources
; i
++) {
380 struct resource
*p
, *r
= &pdev
->resource
[i
];
383 r
->name
= dev_name(&pdev
->dev
);
387 if (resource_type(r
) == IORESOURCE_MEM
)
389 else if (resource_type(r
) == IORESOURCE_IO
)
390 p
= &ioport_resource
;
393 if (p
&& insert_resource(p
, r
)) {
394 dev_err(&pdev
->dev
, "failed to claim resource %d\n", i
);
400 pr_debug("Registering platform device '%s'. Parent at %s\n",
401 dev_name(&pdev
->dev
), dev_name(pdev
->dev
.parent
));
403 ret
= device_add(&pdev
->dev
);
409 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
410 pdev
->id
= PLATFORM_DEVID_AUTO
;
414 struct resource
*r
= &pdev
->resource
[i
];
422 EXPORT_SYMBOL_GPL(platform_device_add
);
425 * platform_device_del - remove a platform-level device
426 * @pdev: platform device we're removing
428 * Note that this function will also release all memory- and port-based
429 * resources owned by the device (@dev->resource). This function must
430 * _only_ be externally called in error cases. All other usage is a bug.
432 void platform_device_del(struct platform_device
*pdev
)
437 device_del(&pdev
->dev
);
440 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
441 pdev
->id
= PLATFORM_DEVID_AUTO
;
444 for (i
= 0; i
< pdev
->num_resources
; i
++) {
445 struct resource
*r
= &pdev
->resource
[i
];
450 device_remove_property_set(&pdev
->dev
);
453 EXPORT_SYMBOL_GPL(platform_device_del
);
456 * platform_device_register - add a platform-level device
457 * @pdev: platform device we're adding
459 int platform_device_register(struct platform_device
*pdev
)
461 device_initialize(&pdev
->dev
);
462 arch_setup_pdev_archdata(pdev
);
463 return platform_device_add(pdev
);
465 EXPORT_SYMBOL_GPL(platform_device_register
);
468 * platform_device_unregister - unregister a platform-level device
469 * @pdev: platform device we're unregistering
471 * Unregistration is done in 2 steps. First we release all resources
472 * and remove it from the subsystem, then we drop reference count by
473 * calling platform_device_put().
475 void platform_device_unregister(struct platform_device
*pdev
)
477 platform_device_del(pdev
);
478 platform_device_put(pdev
);
480 EXPORT_SYMBOL_GPL(platform_device_unregister
);
483 * platform_device_register_full - add a platform-level device with
484 * resources and platform-specific data
486 * @pdevinfo: data used to create device
488 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
490 struct platform_device
*platform_device_register_full(
491 const struct platform_device_info
*pdevinfo
)
494 struct platform_device
*pdev
;
496 pdev
= platform_device_alloc(pdevinfo
->name
, pdevinfo
->id
);
500 pdev
->dev
.parent
= pdevinfo
->parent
;
501 pdev
->dev
.fwnode
= pdevinfo
->fwnode
;
503 if (pdevinfo
->dma_mask
) {
505 * This memory isn't freed when the device is put,
506 * I don't have a nice idea for that though. Conceptually
507 * dma_mask in struct device should not be a pointer.
508 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
511 kmalloc(sizeof(*pdev
->dev
.dma_mask
), GFP_KERNEL
);
512 if (!pdev
->dev
.dma_mask
)
515 *pdev
->dev
.dma_mask
= pdevinfo
->dma_mask
;
516 pdev
->dev
.coherent_dma_mask
= pdevinfo
->dma_mask
;
519 ret
= platform_device_add_resources(pdev
,
520 pdevinfo
->res
, pdevinfo
->num_res
);
524 ret
= platform_device_add_data(pdev
,
525 pdevinfo
->data
, pdevinfo
->size_data
);
529 if (pdevinfo
->pset
) {
530 ret
= platform_device_add_properties(pdev
, pdevinfo
->pset
);
535 ret
= platform_device_add(pdev
);
538 ACPI_COMPANION_SET(&pdev
->dev
, NULL
);
539 kfree(pdev
->dev
.dma_mask
);
542 platform_device_put(pdev
);
548 EXPORT_SYMBOL_GPL(platform_device_register_full
);
550 static int platform_drv_probe(struct device
*_dev
)
552 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
553 struct platform_device
*dev
= to_platform_device(_dev
);
556 ret
= of_clk_set_defaults(_dev
->of_node
, false);
560 ret
= dev_pm_domain_attach(_dev
, true);
561 if (ret
!= -EPROBE_DEFER
) {
563 ret
= drv
->probe(dev
);
565 dev_pm_domain_detach(_dev
, true);
567 /* don't fail if just dev_pm_domain_attach failed */
572 if (drv
->prevent_deferred_probe
&& ret
== -EPROBE_DEFER
) {
573 dev_warn(_dev
, "probe deferral not supported\n");
580 static int platform_drv_probe_fail(struct device
*_dev
)
585 static int platform_drv_remove(struct device
*_dev
)
587 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
588 struct platform_device
*dev
= to_platform_device(_dev
);
592 ret
= drv
->remove(dev
);
593 dev_pm_domain_detach(_dev
, true);
598 static void platform_drv_shutdown(struct device
*_dev
)
600 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
601 struct platform_device
*dev
= to_platform_device(_dev
);
608 * __platform_driver_register - register a driver for platform-level devices
609 * @drv: platform driver structure
610 * @owner: owning module/driver
612 int __platform_driver_register(struct platform_driver
*drv
,
613 struct module
*owner
)
615 drv
->driver
.owner
= owner
;
616 drv
->driver
.bus
= &platform_bus_type
;
617 drv
->driver
.probe
= platform_drv_probe
;
618 drv
->driver
.remove
= platform_drv_remove
;
619 drv
->driver
.shutdown
= platform_drv_shutdown
;
621 return driver_register(&drv
->driver
);
623 EXPORT_SYMBOL_GPL(__platform_driver_register
);
626 * platform_driver_unregister - unregister a driver for platform-level devices
627 * @drv: platform driver structure
629 void platform_driver_unregister(struct platform_driver
*drv
)
631 driver_unregister(&drv
->driver
);
633 EXPORT_SYMBOL_GPL(platform_driver_unregister
);
636 * __platform_driver_probe - register driver for non-hotpluggable device
637 * @drv: platform driver structure
638 * @probe: the driver probe routine, probably from an __init section
639 * @module: module which will be the owner of the driver
641 * Use this instead of platform_driver_register() when you know the device
642 * is not hotpluggable and has already been registered, and you want to
643 * remove its run-once probe() infrastructure from memory after the driver
644 * has bound to the device.
646 * One typical use for this would be with drivers for controllers integrated
647 * into system-on-chip processors, where the controller devices have been
648 * configured as part of board setup.
650 * Note that this is incompatible with deferred probing.
652 * Returns zero if the driver registered and bound to a device, else returns
653 * a negative error code and with the driver not registered.
655 int __init_or_module
__platform_driver_probe(struct platform_driver
*drv
,
656 int (*probe
)(struct platform_device
*), struct module
*module
)
660 if (drv
->driver
.probe_type
== PROBE_PREFER_ASYNCHRONOUS
) {
661 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
662 drv
->driver
.name
, __func__
);
667 * We have to run our probes synchronously because we check if
668 * we find any devices to bind to and exit with error if there
671 drv
->driver
.probe_type
= PROBE_FORCE_SYNCHRONOUS
;
674 * Prevent driver from requesting probe deferral to avoid further
675 * futile probe attempts.
677 drv
->prevent_deferred_probe
= true;
679 /* make sure driver won't have bind/unbind attributes */
680 drv
->driver
.suppress_bind_attrs
= true;
682 /* temporary section violation during probe() */
684 retval
= code
= __platform_driver_register(drv
, module
);
687 * Fixup that section violation, being paranoid about code scanning
688 * the list of drivers in order to probe new devices. Check to see
689 * if the probe was successful, and make sure any forced probes of
692 spin_lock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
694 if (code
== 0 && list_empty(&drv
->driver
.p
->klist_devices
.k_list
))
696 drv
->driver
.probe
= platform_drv_probe_fail
;
697 spin_unlock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
700 platform_driver_unregister(drv
);
703 EXPORT_SYMBOL_GPL(__platform_driver_probe
);
706 * __platform_create_bundle - register driver and create corresponding device
707 * @driver: platform driver structure
708 * @probe: the driver probe routine, probably from an __init section
709 * @res: set of resources that needs to be allocated for the device
710 * @n_res: number of resources
711 * @data: platform specific data for this platform device
712 * @size: size of platform specific data
713 * @module: module which will be the owner of the driver
715 * Use this in legacy-style modules that probe hardware directly and
716 * register a single platform device and corresponding platform driver.
718 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
720 struct platform_device
* __init_or_module
__platform_create_bundle(
721 struct platform_driver
*driver
,
722 int (*probe
)(struct platform_device
*),
723 struct resource
*res
, unsigned int n_res
,
724 const void *data
, size_t size
, struct module
*module
)
726 struct platform_device
*pdev
;
729 pdev
= platform_device_alloc(driver
->driver
.name
, -1);
735 error
= platform_device_add_resources(pdev
, res
, n_res
);
739 error
= platform_device_add_data(pdev
, data
, size
);
743 error
= platform_device_add(pdev
);
747 error
= __platform_driver_probe(driver
, probe
, module
);
754 platform_device_del(pdev
);
756 platform_device_put(pdev
);
758 return ERR_PTR(error
);
760 EXPORT_SYMBOL_GPL(__platform_create_bundle
);
763 * __platform_register_drivers - register an array of platform drivers
764 * @drivers: an array of drivers to register
765 * @count: the number of drivers to register
766 * @owner: module owning the drivers
768 * Registers platform drivers specified by an array. On failure to register a
769 * driver, all previously registered drivers will be unregistered. Callers of
770 * this API should use platform_unregister_drivers() to unregister drivers in
773 * Returns: 0 on success or a negative error code on failure.
775 int __platform_register_drivers(struct platform_driver
* const *drivers
,
776 unsigned int count
, struct module
*owner
)
781 for (i
= 0; i
< count
; i
++) {
782 pr_debug("registering platform driver %ps\n", drivers
[i
]);
784 err
= __platform_driver_register(drivers
[i
], owner
);
786 pr_err("failed to register platform driver %ps: %d\n",
796 pr_debug("unregistering platform driver %ps\n", drivers
[i
]);
797 platform_driver_unregister(drivers
[i
]);
802 EXPORT_SYMBOL_GPL(__platform_register_drivers
);
805 * platform_unregister_drivers - unregister an array of platform drivers
806 * @drivers: an array of drivers to unregister
807 * @count: the number of drivers to unregister
809 * Unegisters platform drivers specified by an array. This is typically used
810 * to complement an earlier call to platform_register_drivers(). Drivers are
811 * unregistered in the reverse order in which they were registered.
813 void platform_unregister_drivers(struct platform_driver
* const *drivers
,
817 pr_debug("unregistering platform driver %ps\n", drivers
[count
]);
818 platform_driver_unregister(drivers
[count
]);
821 EXPORT_SYMBOL_GPL(platform_unregister_drivers
);
823 /* modalias support enables more hands-off userspace setup:
824 * (a) environment variable lets new-style hotplug events work once system is
825 * fully running: "modprobe $MODALIAS"
826 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
827 * mishandled before system is fully running: "modprobe $(cat modalias)"
829 static ssize_t
modalias_show(struct device
*dev
, struct device_attribute
*a
,
832 struct platform_device
*pdev
= to_platform_device(dev
);
835 len
= of_device_get_modalias(dev
, buf
, PAGE_SIZE
-1);
839 len
= acpi_device_modalias(dev
, buf
, PAGE_SIZE
-1);
843 len
= snprintf(buf
, PAGE_SIZE
, "platform:%s\n", pdev
->name
);
845 return (len
>= PAGE_SIZE
) ? (PAGE_SIZE
- 1) : len
;
847 static DEVICE_ATTR_RO(modalias
);
849 static ssize_t
driver_override_store(struct device
*dev
,
850 struct device_attribute
*attr
,
851 const char *buf
, size_t count
)
853 struct platform_device
*pdev
= to_platform_device(dev
);
854 char *driver_override
, *old
= pdev
->driver_override
, *cp
;
856 if (count
> PATH_MAX
)
859 driver_override
= kstrndup(buf
, count
, GFP_KERNEL
);
860 if (!driver_override
)
863 cp
= strchr(driver_override
, '\n');
867 if (strlen(driver_override
)) {
868 pdev
->driver_override
= driver_override
;
870 kfree(driver_override
);
871 pdev
->driver_override
= NULL
;
879 static ssize_t
driver_override_show(struct device
*dev
,
880 struct device_attribute
*attr
, char *buf
)
882 struct platform_device
*pdev
= to_platform_device(dev
);
884 return sprintf(buf
, "%s\n", pdev
->driver_override
);
886 static DEVICE_ATTR_RW(driver_override
);
889 static struct attribute
*platform_dev_attrs
[] = {
890 &dev_attr_modalias
.attr
,
891 &dev_attr_driver_override
.attr
,
894 ATTRIBUTE_GROUPS(platform_dev
);
896 static int platform_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
898 struct platform_device
*pdev
= to_platform_device(dev
);
901 /* Some devices have extra OF data and an OF-style MODALIAS */
902 rc
= of_device_uevent_modalias(dev
, env
);
906 rc
= acpi_device_uevent_modalias(dev
, env
);
910 add_uevent_var(env
, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX
,
915 static const struct platform_device_id
*platform_match_id(
916 const struct platform_device_id
*id
,
917 struct platform_device
*pdev
)
919 while (id
->name
[0]) {
920 if (strcmp(pdev
->name
, id
->name
) == 0) {
930 * platform_match - bind platform device to platform driver.
934 * Platform device IDs are assumed to be encoded like this:
935 * "<name><instance>", where <name> is a short description of the type of
936 * device, like "pci" or "floppy", and <instance> is the enumerated
937 * instance of the device, like '0' or '42'. Driver IDs are simply
938 * "<name>". So, extract the <name> from the platform_device structure,
939 * and compare it against the name of the driver. Return whether they match
942 static int platform_match(struct device
*dev
, struct device_driver
*drv
)
944 struct platform_device
*pdev
= to_platform_device(dev
);
945 struct platform_driver
*pdrv
= to_platform_driver(drv
);
947 /* When driver_override is set, only bind to the matching driver */
948 if (pdev
->driver_override
)
949 return !strcmp(pdev
->driver_override
, drv
->name
);
951 /* Attempt an OF style match first */
952 if (of_driver_match_device(dev
, drv
))
955 /* Then try ACPI style match */
956 if (acpi_driver_match_device(dev
, drv
))
959 /* Then try to match against the id table */
961 return platform_match_id(pdrv
->id_table
, pdev
) != NULL
;
963 /* fall-back to driver name match */
964 return (strcmp(pdev
->name
, drv
->name
) == 0);
967 #ifdef CONFIG_PM_SLEEP
969 static int platform_legacy_suspend(struct device
*dev
, pm_message_t mesg
)
971 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
972 struct platform_device
*pdev
= to_platform_device(dev
);
975 if (dev
->driver
&& pdrv
->suspend
)
976 ret
= pdrv
->suspend(pdev
, mesg
);
981 static int platform_legacy_resume(struct device
*dev
)
983 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
984 struct platform_device
*pdev
= to_platform_device(dev
);
987 if (dev
->driver
&& pdrv
->resume
)
988 ret
= pdrv
->resume(pdev
);
993 #endif /* CONFIG_PM_SLEEP */
995 #ifdef CONFIG_SUSPEND
997 int platform_pm_suspend(struct device
*dev
)
999 struct device_driver
*drv
= dev
->driver
;
1006 if (drv
->pm
->suspend
)
1007 ret
= drv
->pm
->suspend(dev
);
1009 ret
= platform_legacy_suspend(dev
, PMSG_SUSPEND
);
1015 int platform_pm_resume(struct device
*dev
)
1017 struct device_driver
*drv
= dev
->driver
;
1024 if (drv
->pm
->resume
)
1025 ret
= drv
->pm
->resume(dev
);
1027 ret
= platform_legacy_resume(dev
);
1033 #endif /* CONFIG_SUSPEND */
1035 #ifdef CONFIG_HIBERNATE_CALLBACKS
1037 int platform_pm_freeze(struct device
*dev
)
1039 struct device_driver
*drv
= dev
->driver
;
1046 if (drv
->pm
->freeze
)
1047 ret
= drv
->pm
->freeze(dev
);
1049 ret
= platform_legacy_suspend(dev
, PMSG_FREEZE
);
1055 int platform_pm_thaw(struct device
*dev
)
1057 struct device_driver
*drv
= dev
->driver
;
1065 ret
= drv
->pm
->thaw(dev
);
1067 ret
= platform_legacy_resume(dev
);
1073 int platform_pm_poweroff(struct device
*dev
)
1075 struct device_driver
*drv
= dev
->driver
;
1082 if (drv
->pm
->poweroff
)
1083 ret
= drv
->pm
->poweroff(dev
);
1085 ret
= platform_legacy_suspend(dev
, PMSG_HIBERNATE
);
1091 int platform_pm_restore(struct device
*dev
)
1093 struct device_driver
*drv
= dev
->driver
;
1100 if (drv
->pm
->restore
)
1101 ret
= drv
->pm
->restore(dev
);
1103 ret
= platform_legacy_resume(dev
);
1109 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1111 static const struct dev_pm_ops platform_dev_pm_ops
= {
1112 .runtime_suspend
= pm_generic_runtime_suspend
,
1113 .runtime_resume
= pm_generic_runtime_resume
,
1114 USE_PLATFORM_PM_SLEEP_OPS
1117 struct bus_type platform_bus_type
= {
1119 .dev_groups
= platform_dev_groups
,
1120 .match
= platform_match
,
1121 .uevent
= platform_uevent
,
1122 .pm
= &platform_dev_pm_ops
,
1124 EXPORT_SYMBOL_GPL(platform_bus_type
);
1126 int __init
platform_bus_init(void)
1130 early_platform_cleanup();
1132 error
= device_register(&platform_bus
);
1135 error
= bus_register(&platform_bus_type
);
1137 device_unregister(&platform_bus
);
1138 of_platform_register_reconfig_notifier();
1142 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
1143 u64
dma_get_required_mask(struct device
*dev
)
1145 u32 low_totalram
= ((max_pfn
- 1) << PAGE_SHIFT
);
1146 u32 high_totalram
= ((max_pfn
- 1) >> (32 - PAGE_SHIFT
));
1149 if (!high_totalram
) {
1150 /* convert to mask just covering totalram */
1151 low_totalram
= (1 << (fls(low_totalram
) - 1));
1152 low_totalram
+= low_totalram
- 1;
1153 mask
= low_totalram
;
1155 high_totalram
= (1 << (fls(high_totalram
) - 1));
1156 high_totalram
+= high_totalram
- 1;
1157 mask
= (((u64
)high_totalram
) << 32) + 0xffffffff;
1161 EXPORT_SYMBOL_GPL(dma_get_required_mask
);
1164 static __initdata
LIST_HEAD(early_platform_driver_list
);
1165 static __initdata
LIST_HEAD(early_platform_device_list
);
1168 * early_platform_driver_register - register early platform driver
1169 * @epdrv: early_platform driver structure
1170 * @buf: string passed from early_param()
1172 * Helper function for early_platform_init() / early_platform_init_buffer()
1174 int __init
early_platform_driver_register(struct early_platform_driver
*epdrv
,
1180 /* Simply add the driver to the end of the global list.
1181 * Drivers will by default be put on the list in compiled-in order.
1183 if (!epdrv
->list
.next
) {
1184 INIT_LIST_HEAD(&epdrv
->list
);
1185 list_add_tail(&epdrv
->list
, &early_platform_driver_list
);
1188 /* If the user has specified device then make sure the driver
1189 * gets prioritized. The driver of the last device specified on
1190 * command line will be put first on the list.
1192 n
= strlen(epdrv
->pdrv
->driver
.name
);
1193 if (buf
&& !strncmp(buf
, epdrv
->pdrv
->driver
.name
, n
)) {
1194 list_move(&epdrv
->list
, &early_platform_driver_list
);
1196 /* Allow passing parameters after device name */
1197 if (buf
[n
] == '\0' || buf
[n
] == ',')
1198 epdrv
->requested_id
= -1;
1200 epdrv
->requested_id
= simple_strtoul(&buf
[n
+ 1],
1203 if (buf
[n
] != '.' || (tmp
== &buf
[n
+ 1])) {
1204 epdrv
->requested_id
= EARLY_PLATFORM_ID_ERROR
;
1207 n
+= strcspn(&buf
[n
+ 1], ",") + 1;
1213 if (epdrv
->bufsize
) {
1214 memcpy(epdrv
->buffer
, &buf
[n
],
1215 min_t(int, epdrv
->bufsize
, strlen(&buf
[n
]) + 1));
1216 epdrv
->buffer
[epdrv
->bufsize
- 1] = '\0';
1224 * early_platform_add_devices - adds a number of early platform devices
1225 * @devs: array of early platform devices to add
1226 * @num: number of early platform devices in array
1228 * Used by early architecture code to register early platform devices and
1229 * their platform data.
1231 void __init
early_platform_add_devices(struct platform_device
**devs
, int num
)
1236 /* simply add the devices to list */
1237 for (i
= 0; i
< num
; i
++) {
1238 dev
= &devs
[i
]->dev
;
1240 if (!dev
->devres_head
.next
) {
1241 pm_runtime_early_init(dev
);
1242 INIT_LIST_HEAD(&dev
->devres_head
);
1243 list_add_tail(&dev
->devres_head
,
1244 &early_platform_device_list
);
1250 * early_platform_driver_register_all - register early platform drivers
1251 * @class_str: string to identify early platform driver class
1253 * Used by architecture code to register all early platform drivers
1254 * for a certain class. If omitted then only early platform drivers
1255 * with matching kernel command line class parameters will be registered.
1257 void __init
early_platform_driver_register_all(char *class_str
)
1259 /* The "class_str" parameter may or may not be present on the kernel
1260 * command line. If it is present then there may be more than one
1261 * matching parameter.
1263 * Since we register our early platform drivers using early_param()
1264 * we need to make sure that they also get registered in the case
1265 * when the parameter is missing from the kernel command line.
1267 * We use parse_early_options() to make sure the early_param() gets
1268 * called at least once. The early_param() may be called more than
1269 * once since the name of the preferred device may be specified on
1270 * the kernel command line. early_platform_driver_register() handles
1273 parse_early_options(class_str
);
1277 * early_platform_match - find early platform device matching driver
1278 * @epdrv: early platform driver structure
1279 * @id: id to match against
1281 static struct platform_device
* __init
1282 early_platform_match(struct early_platform_driver
*epdrv
, int id
)
1284 struct platform_device
*pd
;
1286 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1287 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1295 * early_platform_left - check if early platform driver has matching devices
1296 * @epdrv: early platform driver structure
1297 * @id: return true if id or above exists
1299 static int __init
early_platform_left(struct early_platform_driver
*epdrv
,
1302 struct platform_device
*pd
;
1304 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1305 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1313 * early_platform_driver_probe_id - probe drivers matching class_str and id
1314 * @class_str: string to identify early platform driver class
1315 * @id: id to match against
1316 * @nr_probe: number of platform devices to successfully probe before exiting
1318 static int __init
early_platform_driver_probe_id(char *class_str
,
1322 struct early_platform_driver
*epdrv
;
1323 struct platform_device
*match
;
1328 list_for_each_entry(epdrv
, &early_platform_driver_list
, list
) {
1329 /* only use drivers matching our class_str */
1330 if (strcmp(class_str
, epdrv
->class_str
))
1334 match_id
= epdrv
->requested_id
;
1339 left
+= early_platform_left(epdrv
, id
);
1341 /* skip requested id */
1342 switch (epdrv
->requested_id
) {
1343 case EARLY_PLATFORM_ID_ERROR
:
1344 case EARLY_PLATFORM_ID_UNSET
:
1347 if (epdrv
->requested_id
== id
)
1348 match_id
= EARLY_PLATFORM_ID_UNSET
;
1353 case EARLY_PLATFORM_ID_ERROR
:
1354 pr_warn("%s: unable to parse %s parameter\n",
1355 class_str
, epdrv
->pdrv
->driver
.name
);
1357 case EARLY_PLATFORM_ID_UNSET
:
1361 match
= early_platform_match(epdrv
, match_id
);
1366 * Set up a sensible init_name to enable
1367 * dev_name() and others to be used before the
1368 * rest of the driver core is initialized.
1370 if (!match
->dev
.init_name
&& slab_is_available()) {
1371 if (match
->id
!= -1)
1372 match
->dev
.init_name
=
1373 kasprintf(GFP_KERNEL
, "%s.%d",
1377 match
->dev
.init_name
=
1378 kasprintf(GFP_KERNEL
, "%s",
1381 if (!match
->dev
.init_name
)
1385 if (epdrv
->pdrv
->probe(match
))
1386 pr_warn("%s: unable to probe %s early.\n",
1387 class_str
, match
->name
);
1403 * early_platform_driver_probe - probe a class of registered drivers
1404 * @class_str: string to identify early platform driver class
1405 * @nr_probe: number of platform devices to successfully probe before exiting
1406 * @user_only: only probe user specified early platform devices
1408 * Used by architecture code to probe registered early platform drivers
1409 * within a certain class. For probe to happen a registered early platform
1410 * device matching a registered early platform driver is needed.
1412 int __init
early_platform_driver_probe(char *class_str
,
1419 for (i
= -2; n
< nr_probe
; i
++) {
1420 k
= early_platform_driver_probe_id(class_str
, i
, nr_probe
- n
);
1435 * early_platform_cleanup - clean up early platform code
1437 void __init
early_platform_cleanup(void)
1439 struct platform_device
*pd
, *pd2
;
1441 /* clean up the devres list used to chain devices */
1442 list_for_each_entry_safe(pd
, pd2
, &early_platform_device_list
,
1444 list_del(&pd
->dev
.devres_head
);
1445 memset(&pd
->dev
.devres_head
, 0, sizeof(pd
->dev
.devres_head
));