1 // SPDX-License-Identifier: GPL-2.0
3 * platform.c - platform 'pseudo' bus for legacy devices
5 * Copyright (c) 2002-3 Patrick Mochel
6 * Copyright (c) 2002-3 Open Source Development Labs
8 * Please see Documentation/driver-api/driver-model/platform.rst for more
12 #include <linux/string.h>
13 #include <linux/platform_device.h>
14 #include <linux/of_device.h>
15 #include <linux/of_irq.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/memblock.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/pm_domain.h>
24 #include <linux/idr.h>
25 #include <linux/acpi.h>
26 #include <linux/clk/clk-conf.h>
27 #include <linux/limits.h>
28 #include <linux/property.h>
29 #include <linux/kmemleak.h>
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 * platform_get_resource - get a resource for a device
44 * @dev: platform device
45 * @type: resource type
46 * @num: resource index
48 struct resource
*platform_get_resource(struct platform_device
*dev
,
49 unsigned int type
, unsigned int num
)
53 for (i
= 0; i
< dev
->num_resources
; i
++) {
54 struct resource
*r
= &dev
->resource
[i
];
56 if (type
== resource_type(r
) && num
-- == 0)
61 EXPORT_SYMBOL_GPL(platform_get_resource
);
64 * devm_platform_ioremap_resource - call devm_ioremap_resource() for a platform
67 * @pdev: platform device to use both for memory resource lookup as well as
69 * @index: resource index
71 #ifdef CONFIG_HAS_IOMEM
72 void __iomem
*devm_platform_ioremap_resource(struct platform_device
*pdev
,
77 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, index
);
78 return devm_ioremap_resource(&pdev
->dev
, res
);
80 EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource
);
81 #endif /* CONFIG_HAS_IOMEM */
83 static int __platform_get_irq(struct platform_device
*dev
, unsigned int num
)
86 /* sparc does not have irqs represented as IORESOURCE_IRQ resources */
87 if (!dev
|| num
>= dev
->archdata
.num_irqs
)
89 return dev
->archdata
.irqs
[num
];
92 if (IS_ENABLED(CONFIG_OF_IRQ
) && dev
->dev
.of_node
) {
95 ret
= of_irq_get(dev
->dev
.of_node
, num
);
96 if (ret
> 0 || ret
== -EPROBE_DEFER
)
100 r
= platform_get_resource(dev
, IORESOURCE_IRQ
, num
);
101 if (has_acpi_companion(&dev
->dev
)) {
102 if (r
&& r
->flags
& IORESOURCE_DISABLED
) {
105 ret
= acpi_irq_get(ACPI_HANDLE(&dev
->dev
), num
, r
);
112 * The resources may pass trigger flags to the irqs that need
113 * to be set up. It so happens that the trigger flags for
114 * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
117 if (r
&& r
->flags
& IORESOURCE_BITS
) {
118 struct irq_data
*irqd
;
120 irqd
= irq_get_irq_data(r
->start
);
123 irqd_set_trigger_type(irqd
, r
->flags
& IORESOURCE_BITS
);
130 * For the index 0 interrupt, allow falling back to GpioInt
131 * resources. While a device could have both Interrupt and GpioInt
132 * resources, making this fallback ambiguous, in many common cases
133 * the device will only expose one IRQ, and this fallback
134 * allows a common code path across either kind of resource.
136 if (num
== 0 && has_acpi_companion(&dev
->dev
)) {
137 int ret
= acpi_dev_gpio_irq_get(ACPI_COMPANION(&dev
->dev
), num
);
139 /* Our callers expect -ENXIO for missing IRQs. */
140 if (ret
>= 0 || ret
== -EPROBE_DEFER
)
149 * platform_get_irq - get an IRQ for a device
150 * @dev: platform device
151 * @num: IRQ number index
153 * Gets an IRQ for a platform device and prints an error message if finding the
154 * IRQ fails. Device drivers should check the return value for errors so as to
155 * not pass a negative integer value to the request_irq() APIs.
158 * int irq = platform_get_irq(pdev, 0);
162 * Return: IRQ number on success, negative error number on failure.
164 int platform_get_irq(struct platform_device
*dev
, unsigned int num
)
168 ret
= __platform_get_irq(dev
, num
);
169 if (ret
< 0 && ret
!= -EPROBE_DEFER
)
170 dev_err(&dev
->dev
, "IRQ index %u not found\n", num
);
174 EXPORT_SYMBOL_GPL(platform_get_irq
);
177 * platform_get_irq_optional - get an optional IRQ for a device
178 * @dev: platform device
179 * @num: IRQ number index
181 * Gets an IRQ for a platform device. Device drivers should check the return
182 * value for errors so as to not pass a negative integer value to the
183 * request_irq() APIs. This is the same as platform_get_irq(), except that it
184 * does not print an error message if an IRQ can not be obtained.
187 * int irq = platform_get_irq_optional(pdev, 0);
191 * Return: IRQ number on success, negative error number on failure.
193 int platform_get_irq_optional(struct platform_device
*dev
, unsigned int num
)
195 return __platform_get_irq(dev
, num
);
197 EXPORT_SYMBOL_GPL(platform_get_irq_optional
);
200 * platform_irq_count - Count the number of IRQs a platform device uses
201 * @dev: platform device
203 * Return: Number of IRQs a platform device uses or EPROBE_DEFER
205 int platform_irq_count(struct platform_device
*dev
)
209 while ((ret
= __platform_get_irq(dev
, nr
)) >= 0)
212 if (ret
== -EPROBE_DEFER
)
217 EXPORT_SYMBOL_GPL(platform_irq_count
);
220 * platform_get_resource_byname - get a resource for a device by name
221 * @dev: platform device
222 * @type: resource type
223 * @name: resource name
225 struct resource
*platform_get_resource_byname(struct platform_device
*dev
,
231 for (i
= 0; i
< dev
->num_resources
; i
++) {
232 struct resource
*r
= &dev
->resource
[i
];
234 if (unlikely(!r
->name
))
237 if (type
== resource_type(r
) && !strcmp(r
->name
, name
))
242 EXPORT_SYMBOL_GPL(platform_get_resource_byname
);
245 * platform_get_irq_byname - get an IRQ for a device by name
246 * @dev: platform device
249 int platform_get_irq_byname(struct platform_device
*dev
, const char *name
)
253 if (IS_ENABLED(CONFIG_OF_IRQ
) && dev
->dev
.of_node
) {
256 ret
= of_irq_get_byname(dev
->dev
.of_node
, name
);
257 if (ret
> 0 || ret
== -EPROBE_DEFER
)
261 r
= platform_get_resource_byname(dev
, IORESOURCE_IRQ
, name
);
265 dev_err(&dev
->dev
, "IRQ %s not found\n", name
);
268 EXPORT_SYMBOL_GPL(platform_get_irq_byname
);
271 * platform_add_devices - add a numbers of platform devices
272 * @devs: array of platform devices to add
273 * @num: number of platform devices in array
275 int platform_add_devices(struct platform_device
**devs
, int num
)
279 for (i
= 0; i
< num
; i
++) {
280 ret
= platform_device_register(devs
[i
]);
283 platform_device_unregister(devs
[i
]);
290 EXPORT_SYMBOL_GPL(platform_add_devices
);
292 struct platform_object
{
293 struct platform_device pdev
;
298 * Set up default DMA mask for platform devices if the they weren't
299 * previously set by the architecture / DT.
301 static void setup_pdev_dma_masks(struct platform_device
*pdev
)
303 if (!pdev
->dev
.coherent_dma_mask
)
304 pdev
->dev
.coherent_dma_mask
= DMA_BIT_MASK(32);
306 pdev
->dma_mask
= DMA_BIT_MASK(32);
307 if (!pdev
->dev
.dma_mask
)
308 pdev
->dev
.dma_mask
= &pdev
->dma_mask
;
312 * platform_device_put - destroy a platform device
313 * @pdev: platform device to free
315 * Free all memory associated with a platform device. This function must
316 * _only_ be externally called in error cases. All other usage is a bug.
318 void platform_device_put(struct platform_device
*pdev
)
320 if (!IS_ERR_OR_NULL(pdev
))
321 put_device(&pdev
->dev
);
323 EXPORT_SYMBOL_GPL(platform_device_put
);
325 static void platform_device_release(struct device
*dev
)
327 struct platform_object
*pa
= container_of(dev
, struct platform_object
,
330 of_device_node_put(&pa
->pdev
.dev
);
331 kfree(pa
->pdev
.dev
.platform_data
);
332 kfree(pa
->pdev
.mfd_cell
);
333 kfree(pa
->pdev
.resource
);
334 kfree(pa
->pdev
.driver_override
);
339 * platform_device_alloc - create a platform device
340 * @name: base name of the device we're adding
343 * Create a platform device object which can have other objects attached
344 * to it, and which will have attached objects freed when it is released.
346 struct platform_device
*platform_device_alloc(const char *name
, int id
)
348 struct platform_object
*pa
;
350 pa
= kzalloc(sizeof(*pa
) + strlen(name
) + 1, GFP_KERNEL
);
352 strcpy(pa
->name
, name
);
353 pa
->pdev
.name
= pa
->name
;
355 device_initialize(&pa
->pdev
.dev
);
356 pa
->pdev
.dev
.release
= platform_device_release
;
357 setup_pdev_dma_masks(&pa
->pdev
);
360 return pa
? &pa
->pdev
: NULL
;
362 EXPORT_SYMBOL_GPL(platform_device_alloc
);
365 * platform_device_add_resources - add resources to a platform device
366 * @pdev: platform device allocated by platform_device_alloc to add resources to
367 * @res: set of resources that needs to be allocated for the device
368 * @num: number of resources
370 * Add a copy of the resources to the platform device. The memory
371 * associated with the resources will be freed when the platform device is
374 int platform_device_add_resources(struct platform_device
*pdev
,
375 const struct resource
*res
, unsigned int num
)
377 struct resource
*r
= NULL
;
380 r
= kmemdup(res
, sizeof(struct resource
) * num
, GFP_KERNEL
);
385 kfree(pdev
->resource
);
387 pdev
->num_resources
= num
;
390 EXPORT_SYMBOL_GPL(platform_device_add_resources
);
393 * platform_device_add_data - add platform-specific data to a platform device
394 * @pdev: platform device allocated by platform_device_alloc to add resources to
395 * @data: platform specific data for this platform device
396 * @size: size of platform specific data
398 * Add a copy of platform specific data to the platform device's
399 * platform_data pointer. The memory associated with the platform data
400 * will be freed when the platform device is released.
402 int platform_device_add_data(struct platform_device
*pdev
, const void *data
,
408 d
= kmemdup(data
, size
, GFP_KERNEL
);
413 kfree(pdev
->dev
.platform_data
);
414 pdev
->dev
.platform_data
= d
;
417 EXPORT_SYMBOL_GPL(platform_device_add_data
);
420 * platform_device_add_properties - add built-in properties to a platform device
421 * @pdev: platform device to add properties to
422 * @properties: null terminated array of properties to add
424 * The function will take deep copy of @properties and attach the copy to the
425 * platform device. The memory associated with properties will be freed when the
426 * platform device is released.
428 int platform_device_add_properties(struct platform_device
*pdev
,
429 const struct property_entry
*properties
)
431 return device_add_properties(&pdev
->dev
, properties
);
433 EXPORT_SYMBOL_GPL(platform_device_add_properties
);
436 * platform_device_add - add a platform device to device hierarchy
437 * @pdev: platform device we're adding
439 * This is part 2 of platform_device_register(), though may be called
440 * separately _iff_ pdev was allocated by platform_device_alloc().
442 int platform_device_add(struct platform_device
*pdev
)
449 if (!pdev
->dev
.parent
)
450 pdev
->dev
.parent
= &platform_bus
;
452 pdev
->dev
.bus
= &platform_bus_type
;
456 dev_set_name(&pdev
->dev
, "%s.%d", pdev
->name
, pdev
->id
);
458 case PLATFORM_DEVID_NONE
:
459 dev_set_name(&pdev
->dev
, "%s", pdev
->name
);
461 case PLATFORM_DEVID_AUTO
:
463 * Automatically allocated device ID. We mark it as such so
464 * that we remember it must be freed, and we append a suffix
465 * to avoid namespace collision with explicit IDs.
467 ret
= ida_simple_get(&platform_devid_ida
, 0, 0, GFP_KERNEL
);
471 pdev
->id_auto
= true;
472 dev_set_name(&pdev
->dev
, "%s.%d.auto", pdev
->name
, pdev
->id
);
476 for (i
= 0; i
< pdev
->num_resources
; i
++) {
477 struct resource
*p
, *r
= &pdev
->resource
[i
];
480 r
->name
= dev_name(&pdev
->dev
);
484 if (resource_type(r
) == IORESOURCE_MEM
)
486 else if (resource_type(r
) == IORESOURCE_IO
)
487 p
= &ioport_resource
;
491 ret
= insert_resource(p
, r
);
493 dev_err(&pdev
->dev
, "failed to claim resource %d: %pR\n", i
, r
);
499 pr_debug("Registering platform device '%s'. Parent at %s\n",
500 dev_name(&pdev
->dev
), dev_name(pdev
->dev
.parent
));
502 ret
= device_add(&pdev
->dev
);
508 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
509 pdev
->id
= PLATFORM_DEVID_AUTO
;
513 struct resource
*r
= &pdev
->resource
[i
];
521 EXPORT_SYMBOL_GPL(platform_device_add
);
524 * platform_device_del - remove a platform-level device
525 * @pdev: platform device we're removing
527 * Note that this function will also release all memory- and port-based
528 * resources owned by the device (@dev->resource). This function must
529 * _only_ be externally called in error cases. All other usage is a bug.
531 void platform_device_del(struct platform_device
*pdev
)
535 if (!IS_ERR_OR_NULL(pdev
)) {
536 device_del(&pdev
->dev
);
539 ida_simple_remove(&platform_devid_ida
, pdev
->id
);
540 pdev
->id
= PLATFORM_DEVID_AUTO
;
543 for (i
= 0; i
< pdev
->num_resources
; i
++) {
544 struct resource
*r
= &pdev
->resource
[i
];
550 EXPORT_SYMBOL_GPL(platform_device_del
);
553 * platform_device_register - add a platform-level device
554 * @pdev: platform device we're adding
556 int platform_device_register(struct platform_device
*pdev
)
558 device_initialize(&pdev
->dev
);
559 setup_pdev_dma_masks(pdev
);
560 return platform_device_add(pdev
);
562 EXPORT_SYMBOL_GPL(platform_device_register
);
565 * platform_device_unregister - unregister a platform-level device
566 * @pdev: platform device we're unregistering
568 * Unregistration is done in 2 steps. First we release all resources
569 * and remove it from the subsystem, then we drop reference count by
570 * calling platform_device_put().
572 void platform_device_unregister(struct platform_device
*pdev
)
574 platform_device_del(pdev
);
575 platform_device_put(pdev
);
577 EXPORT_SYMBOL_GPL(platform_device_unregister
);
580 * platform_device_register_full - add a platform-level device with
581 * resources and platform-specific data
583 * @pdevinfo: data used to create device
585 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
587 struct platform_device
*platform_device_register_full(
588 const struct platform_device_info
*pdevinfo
)
591 struct platform_device
*pdev
;
593 pdev
= platform_device_alloc(pdevinfo
->name
, pdevinfo
->id
);
595 return ERR_PTR(-ENOMEM
);
597 pdev
->dev
.parent
= pdevinfo
->parent
;
598 pdev
->dev
.fwnode
= pdevinfo
->fwnode
;
599 pdev
->dev
.of_node
= of_node_get(to_of_node(pdev
->dev
.fwnode
));
600 pdev
->dev
.of_node_reused
= pdevinfo
->of_node_reused
;
602 if (pdevinfo
->dma_mask
) {
604 * This memory isn't freed when the device is put,
605 * I don't have a nice idea for that though. Conceptually
606 * dma_mask in struct device should not be a pointer.
607 * See http://thread.gmane.org/gmane.linux.kernel.pci/9081
610 kmalloc(sizeof(*pdev
->dev
.dma_mask
), GFP_KERNEL
);
611 if (!pdev
->dev
.dma_mask
)
614 kmemleak_ignore(pdev
->dev
.dma_mask
);
616 *pdev
->dev
.dma_mask
= pdevinfo
->dma_mask
;
617 pdev
->dev
.coherent_dma_mask
= pdevinfo
->dma_mask
;
620 ret
= platform_device_add_resources(pdev
,
621 pdevinfo
->res
, pdevinfo
->num_res
);
625 ret
= platform_device_add_data(pdev
,
626 pdevinfo
->data
, pdevinfo
->size_data
);
630 if (pdevinfo
->properties
) {
631 ret
= platform_device_add_properties(pdev
,
632 pdevinfo
->properties
);
637 ret
= platform_device_add(pdev
);
640 ACPI_COMPANION_SET(&pdev
->dev
, NULL
);
641 kfree(pdev
->dev
.dma_mask
);
642 platform_device_put(pdev
);
648 EXPORT_SYMBOL_GPL(platform_device_register_full
);
650 static int platform_drv_probe(struct device
*_dev
)
652 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
653 struct platform_device
*dev
= to_platform_device(_dev
);
656 ret
= of_clk_set_defaults(_dev
->of_node
, false);
660 ret
= dev_pm_domain_attach(_dev
, true);
665 ret
= drv
->probe(dev
);
667 dev_pm_domain_detach(_dev
, true);
671 if (drv
->prevent_deferred_probe
&& ret
== -EPROBE_DEFER
) {
672 dev_warn(_dev
, "probe deferral not supported\n");
679 static int platform_drv_probe_fail(struct device
*_dev
)
684 static int platform_drv_remove(struct device
*_dev
)
686 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
687 struct platform_device
*dev
= to_platform_device(_dev
);
691 ret
= drv
->remove(dev
);
692 dev_pm_domain_detach(_dev
, true);
697 static void platform_drv_shutdown(struct device
*_dev
)
699 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
700 struct platform_device
*dev
= to_platform_device(_dev
);
707 * __platform_driver_register - register a driver for platform-level devices
708 * @drv: platform driver structure
709 * @owner: owning module/driver
711 int __platform_driver_register(struct platform_driver
*drv
,
712 struct module
*owner
)
714 drv
->driver
.owner
= owner
;
715 drv
->driver
.bus
= &platform_bus_type
;
716 drv
->driver
.probe
= platform_drv_probe
;
717 drv
->driver
.remove
= platform_drv_remove
;
718 drv
->driver
.shutdown
= platform_drv_shutdown
;
720 return driver_register(&drv
->driver
);
722 EXPORT_SYMBOL_GPL(__platform_driver_register
);
725 * platform_driver_unregister - unregister a driver for platform-level devices
726 * @drv: platform driver structure
728 void platform_driver_unregister(struct platform_driver
*drv
)
730 driver_unregister(&drv
->driver
);
732 EXPORT_SYMBOL_GPL(platform_driver_unregister
);
735 * __platform_driver_probe - register driver for non-hotpluggable device
736 * @drv: platform driver structure
737 * @probe: the driver probe routine, probably from an __init section
738 * @module: module which will be the owner of the driver
740 * Use this instead of platform_driver_register() when you know the device
741 * is not hotpluggable and has already been registered, and you want to
742 * remove its run-once probe() infrastructure from memory after the driver
743 * has bound to the device.
745 * One typical use for this would be with drivers for controllers integrated
746 * into system-on-chip processors, where the controller devices have been
747 * configured as part of board setup.
749 * Note that this is incompatible with deferred probing.
751 * Returns zero if the driver registered and bound to a device, else returns
752 * a negative error code and with the driver not registered.
754 int __init_or_module
__platform_driver_probe(struct platform_driver
*drv
,
755 int (*probe
)(struct platform_device
*), struct module
*module
)
759 if (drv
->driver
.probe_type
== PROBE_PREFER_ASYNCHRONOUS
) {
760 pr_err("%s: drivers registered with %s can not be probed asynchronously\n",
761 drv
->driver
.name
, __func__
);
766 * We have to run our probes synchronously because we check if
767 * we find any devices to bind to and exit with error if there
770 drv
->driver
.probe_type
= PROBE_FORCE_SYNCHRONOUS
;
773 * Prevent driver from requesting probe deferral to avoid further
774 * futile probe attempts.
776 drv
->prevent_deferred_probe
= true;
778 /* make sure driver won't have bind/unbind attributes */
779 drv
->driver
.suppress_bind_attrs
= true;
781 /* temporary section violation during probe() */
783 retval
= code
= __platform_driver_register(drv
, module
);
786 * Fixup that section violation, being paranoid about code scanning
787 * the list of drivers in order to probe new devices. Check to see
788 * if the probe was successful, and make sure any forced probes of
791 spin_lock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
793 if (code
== 0 && list_empty(&drv
->driver
.p
->klist_devices
.k_list
))
795 drv
->driver
.probe
= platform_drv_probe_fail
;
796 spin_unlock(&drv
->driver
.bus
->p
->klist_drivers
.k_lock
);
799 platform_driver_unregister(drv
);
802 EXPORT_SYMBOL_GPL(__platform_driver_probe
);
805 * __platform_create_bundle - register driver and create corresponding device
806 * @driver: platform driver structure
807 * @probe: the driver probe routine, probably from an __init section
808 * @res: set of resources that needs to be allocated for the device
809 * @n_res: number of resources
810 * @data: platform specific data for this platform device
811 * @size: size of platform specific data
812 * @module: module which will be the owner of the driver
814 * Use this in legacy-style modules that probe hardware directly and
815 * register a single platform device and corresponding platform driver.
817 * Returns &struct platform_device pointer on success, or ERR_PTR() on error.
819 struct platform_device
* __init_or_module
__platform_create_bundle(
820 struct platform_driver
*driver
,
821 int (*probe
)(struct platform_device
*),
822 struct resource
*res
, unsigned int n_res
,
823 const void *data
, size_t size
, struct module
*module
)
825 struct platform_device
*pdev
;
828 pdev
= platform_device_alloc(driver
->driver
.name
, -1);
834 error
= platform_device_add_resources(pdev
, res
, n_res
);
838 error
= platform_device_add_data(pdev
, data
, size
);
842 error
= platform_device_add(pdev
);
846 error
= __platform_driver_probe(driver
, probe
, module
);
853 platform_device_del(pdev
);
855 platform_device_put(pdev
);
857 return ERR_PTR(error
);
859 EXPORT_SYMBOL_GPL(__platform_create_bundle
);
862 * __platform_register_drivers - register an array of platform drivers
863 * @drivers: an array of drivers to register
864 * @count: the number of drivers to register
865 * @owner: module owning the drivers
867 * Registers platform drivers specified by an array. On failure to register a
868 * driver, all previously registered drivers will be unregistered. Callers of
869 * this API should use platform_unregister_drivers() to unregister drivers in
872 * Returns: 0 on success or a negative error code on failure.
874 int __platform_register_drivers(struct platform_driver
* const *drivers
,
875 unsigned int count
, struct module
*owner
)
880 for (i
= 0; i
< count
; i
++) {
881 pr_debug("registering platform driver %ps\n", drivers
[i
]);
883 err
= __platform_driver_register(drivers
[i
], owner
);
885 pr_err("failed to register platform driver %ps: %d\n",
895 pr_debug("unregistering platform driver %ps\n", drivers
[i
]);
896 platform_driver_unregister(drivers
[i
]);
901 EXPORT_SYMBOL_GPL(__platform_register_drivers
);
904 * platform_unregister_drivers - unregister an array of platform drivers
905 * @drivers: an array of drivers to unregister
906 * @count: the number of drivers to unregister
908 * Unegisters platform drivers specified by an array. This is typically used
909 * to complement an earlier call to platform_register_drivers(). Drivers are
910 * unregistered in the reverse order in which they were registered.
912 void platform_unregister_drivers(struct platform_driver
* const *drivers
,
916 pr_debug("unregistering platform driver %ps\n", drivers
[count
]);
917 platform_driver_unregister(drivers
[count
]);
920 EXPORT_SYMBOL_GPL(platform_unregister_drivers
);
922 /* modalias support enables more hands-off userspace setup:
923 * (a) environment variable lets new-style hotplug events work once system is
924 * fully running: "modprobe $MODALIAS"
925 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
926 * mishandled before system is fully running: "modprobe $(cat modalias)"
928 static ssize_t
modalias_show(struct device
*dev
, struct device_attribute
*a
,
931 struct platform_device
*pdev
= to_platform_device(dev
);
934 len
= of_device_modalias(dev
, buf
, PAGE_SIZE
);
938 len
= acpi_device_modalias(dev
, buf
, PAGE_SIZE
-1);
942 len
= snprintf(buf
, PAGE_SIZE
, "platform:%s\n", pdev
->name
);
944 return (len
>= PAGE_SIZE
) ? (PAGE_SIZE
- 1) : len
;
946 static DEVICE_ATTR_RO(modalias
);
948 static ssize_t
driver_override_store(struct device
*dev
,
949 struct device_attribute
*attr
,
950 const char *buf
, size_t count
)
952 struct platform_device
*pdev
= to_platform_device(dev
);
953 char *driver_override
, *old
, *cp
;
955 /* We need to keep extra room for a newline */
956 if (count
>= (PAGE_SIZE
- 1))
959 driver_override
= kstrndup(buf
, count
, GFP_KERNEL
);
960 if (!driver_override
)
963 cp
= strchr(driver_override
, '\n');
968 old
= pdev
->driver_override
;
969 if (strlen(driver_override
)) {
970 pdev
->driver_override
= driver_override
;
972 kfree(driver_override
);
973 pdev
->driver_override
= NULL
;
982 static ssize_t
driver_override_show(struct device
*dev
,
983 struct device_attribute
*attr
, char *buf
)
985 struct platform_device
*pdev
= to_platform_device(dev
);
989 len
= sprintf(buf
, "%s\n", pdev
->driver_override
);
993 static DEVICE_ATTR_RW(driver_override
);
996 static struct attribute
*platform_dev_attrs
[] = {
997 &dev_attr_modalias
.attr
,
998 &dev_attr_driver_override
.attr
,
1001 ATTRIBUTE_GROUPS(platform_dev
);
1003 static int platform_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
1005 struct platform_device
*pdev
= to_platform_device(dev
);
1008 /* Some devices have extra OF data and an OF-style MODALIAS */
1009 rc
= of_device_uevent_modalias(dev
, env
);
1013 rc
= acpi_device_uevent_modalias(dev
, env
);
1017 add_uevent_var(env
, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX
,
1022 static const struct platform_device_id
*platform_match_id(
1023 const struct platform_device_id
*id
,
1024 struct platform_device
*pdev
)
1026 while (id
->name
[0]) {
1027 if (strcmp(pdev
->name
, id
->name
) == 0) {
1028 pdev
->id_entry
= id
;
1037 * platform_match - bind platform device to platform driver.
1041 * Platform device IDs are assumed to be encoded like this:
1042 * "<name><instance>", where <name> is a short description of the type of
1043 * device, like "pci" or "floppy", and <instance> is the enumerated
1044 * instance of the device, like '0' or '42'. Driver IDs are simply
1045 * "<name>". So, extract the <name> from the platform_device structure,
1046 * and compare it against the name of the driver. Return whether they match
1049 static int platform_match(struct device
*dev
, struct device_driver
*drv
)
1051 struct platform_device
*pdev
= to_platform_device(dev
);
1052 struct platform_driver
*pdrv
= to_platform_driver(drv
);
1054 /* When driver_override is set, only bind to the matching driver */
1055 if (pdev
->driver_override
)
1056 return !strcmp(pdev
->driver_override
, drv
->name
);
1058 /* Attempt an OF style match first */
1059 if (of_driver_match_device(dev
, drv
))
1062 /* Then try ACPI style match */
1063 if (acpi_driver_match_device(dev
, drv
))
1066 /* Then try to match against the id table */
1068 return platform_match_id(pdrv
->id_table
, pdev
) != NULL
;
1070 /* fall-back to driver name match */
1071 return (strcmp(pdev
->name
, drv
->name
) == 0);
1074 #ifdef CONFIG_PM_SLEEP
1076 static int platform_legacy_suspend(struct device
*dev
, pm_message_t mesg
)
1078 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
1079 struct platform_device
*pdev
= to_platform_device(dev
);
1082 if (dev
->driver
&& pdrv
->suspend
)
1083 ret
= pdrv
->suspend(pdev
, mesg
);
1088 static int platform_legacy_resume(struct device
*dev
)
1090 struct platform_driver
*pdrv
= to_platform_driver(dev
->driver
);
1091 struct platform_device
*pdev
= to_platform_device(dev
);
1094 if (dev
->driver
&& pdrv
->resume
)
1095 ret
= pdrv
->resume(pdev
);
1100 #endif /* CONFIG_PM_SLEEP */
1102 #ifdef CONFIG_SUSPEND
1104 int platform_pm_suspend(struct device
*dev
)
1106 struct device_driver
*drv
= dev
->driver
;
1113 if (drv
->pm
->suspend
)
1114 ret
= drv
->pm
->suspend(dev
);
1116 ret
= platform_legacy_suspend(dev
, PMSG_SUSPEND
);
1122 int platform_pm_resume(struct device
*dev
)
1124 struct device_driver
*drv
= dev
->driver
;
1131 if (drv
->pm
->resume
)
1132 ret
= drv
->pm
->resume(dev
);
1134 ret
= platform_legacy_resume(dev
);
1140 #endif /* CONFIG_SUSPEND */
1142 #ifdef CONFIG_HIBERNATE_CALLBACKS
1144 int platform_pm_freeze(struct device
*dev
)
1146 struct device_driver
*drv
= dev
->driver
;
1153 if (drv
->pm
->freeze
)
1154 ret
= drv
->pm
->freeze(dev
);
1156 ret
= platform_legacy_suspend(dev
, PMSG_FREEZE
);
1162 int platform_pm_thaw(struct device
*dev
)
1164 struct device_driver
*drv
= dev
->driver
;
1172 ret
= drv
->pm
->thaw(dev
);
1174 ret
= platform_legacy_resume(dev
);
1180 int platform_pm_poweroff(struct device
*dev
)
1182 struct device_driver
*drv
= dev
->driver
;
1189 if (drv
->pm
->poweroff
)
1190 ret
= drv
->pm
->poweroff(dev
);
1192 ret
= platform_legacy_suspend(dev
, PMSG_HIBERNATE
);
1198 int platform_pm_restore(struct device
*dev
)
1200 struct device_driver
*drv
= dev
->driver
;
1207 if (drv
->pm
->restore
)
1208 ret
= drv
->pm
->restore(dev
);
1210 ret
= platform_legacy_resume(dev
);
1216 #endif /* CONFIG_HIBERNATE_CALLBACKS */
1218 int platform_dma_configure(struct device
*dev
)
1220 enum dev_dma_attr attr
;
1224 ret
= of_dma_configure(dev
, dev
->of_node
, true);
1225 } else if (has_acpi_companion(dev
)) {
1226 attr
= acpi_get_dma_attr(to_acpi_device_node(dev
->fwnode
));
1227 ret
= acpi_dma_configure(dev
, attr
);
1233 static const struct dev_pm_ops platform_dev_pm_ops
= {
1234 .runtime_suspend
= pm_generic_runtime_suspend
,
1235 .runtime_resume
= pm_generic_runtime_resume
,
1236 USE_PLATFORM_PM_SLEEP_OPS
1239 struct bus_type platform_bus_type
= {
1241 .dev_groups
= platform_dev_groups
,
1242 .match
= platform_match
,
1243 .uevent
= platform_uevent
,
1244 .dma_configure
= platform_dma_configure
,
1245 .pm
= &platform_dev_pm_ops
,
1247 EXPORT_SYMBOL_GPL(platform_bus_type
);
1250 * platform_find_device_by_driver - Find a platform device with a given
1252 * @start: The device to start the search from.
1253 * @drv: The device driver to look for.
1255 struct device
*platform_find_device_by_driver(struct device
*start
,
1256 const struct device_driver
*drv
)
1258 return bus_find_device(&platform_bus_type
, start
, drv
,
1259 (void *)platform_match
);
1261 EXPORT_SYMBOL_GPL(platform_find_device_by_driver
);
1263 int __init
platform_bus_init(void)
1267 early_platform_cleanup();
1269 error
= device_register(&platform_bus
);
1271 put_device(&platform_bus
);
1274 error
= bus_register(&platform_bus_type
);
1276 device_unregister(&platform_bus
);
1277 of_platform_register_reconfig_notifier();
1281 static __initdata
LIST_HEAD(early_platform_driver_list
);
1282 static __initdata
LIST_HEAD(early_platform_device_list
);
1285 * early_platform_driver_register - register early platform driver
1286 * @epdrv: early_platform driver structure
1287 * @buf: string passed from early_param()
1289 * Helper function for early_platform_init() / early_platform_init_buffer()
1291 int __init
early_platform_driver_register(struct early_platform_driver
*epdrv
,
1297 /* Simply add the driver to the end of the global list.
1298 * Drivers will by default be put on the list in compiled-in order.
1300 if (!epdrv
->list
.next
) {
1301 INIT_LIST_HEAD(&epdrv
->list
);
1302 list_add_tail(&epdrv
->list
, &early_platform_driver_list
);
1305 /* If the user has specified device then make sure the driver
1306 * gets prioritized. The driver of the last device specified on
1307 * command line will be put first on the list.
1309 n
= strlen(epdrv
->pdrv
->driver
.name
);
1310 if (buf
&& !strncmp(buf
, epdrv
->pdrv
->driver
.name
, n
)) {
1311 list_move(&epdrv
->list
, &early_platform_driver_list
);
1313 /* Allow passing parameters after device name */
1314 if (buf
[n
] == '\0' || buf
[n
] == ',')
1315 epdrv
->requested_id
= -1;
1317 epdrv
->requested_id
= simple_strtoul(&buf
[n
+ 1],
1320 if (buf
[n
] != '.' || (tmp
== &buf
[n
+ 1])) {
1321 epdrv
->requested_id
= EARLY_PLATFORM_ID_ERROR
;
1324 n
+= strcspn(&buf
[n
+ 1], ",") + 1;
1330 if (epdrv
->bufsize
) {
1331 memcpy(epdrv
->buffer
, &buf
[n
],
1332 min_t(int, epdrv
->bufsize
, strlen(&buf
[n
]) + 1));
1333 epdrv
->buffer
[epdrv
->bufsize
- 1] = '\0';
1341 * early_platform_add_devices - adds a number of early platform devices
1342 * @devs: array of early platform devices to add
1343 * @num: number of early platform devices in array
1345 * Used by early architecture code to register early platform devices and
1346 * their platform data.
1348 void __init
early_platform_add_devices(struct platform_device
**devs
, int num
)
1353 /* simply add the devices to list */
1354 for (i
= 0; i
< num
; i
++) {
1355 dev
= &devs
[i
]->dev
;
1357 if (!dev
->devres_head
.next
) {
1358 pm_runtime_early_init(dev
);
1359 INIT_LIST_HEAD(&dev
->devres_head
);
1360 list_add_tail(&dev
->devres_head
,
1361 &early_platform_device_list
);
1367 * early_platform_driver_register_all - register early platform drivers
1368 * @class_str: string to identify early platform driver class
1370 * Used by architecture code to register all early platform drivers
1371 * for a certain class. If omitted then only early platform drivers
1372 * with matching kernel command line class parameters will be registered.
1374 void __init
early_platform_driver_register_all(char *class_str
)
1376 /* The "class_str" parameter may or may not be present on the kernel
1377 * command line. If it is present then there may be more than one
1378 * matching parameter.
1380 * Since we register our early platform drivers using early_param()
1381 * we need to make sure that they also get registered in the case
1382 * when the parameter is missing from the kernel command line.
1384 * We use parse_early_options() to make sure the early_param() gets
1385 * called at least once. The early_param() may be called more than
1386 * once since the name of the preferred device may be specified on
1387 * the kernel command line. early_platform_driver_register() handles
1390 parse_early_options(class_str
);
1394 * early_platform_match - find early platform device matching driver
1395 * @epdrv: early platform driver structure
1396 * @id: id to match against
1398 static struct platform_device
* __init
1399 early_platform_match(struct early_platform_driver
*epdrv
, int id
)
1401 struct platform_device
*pd
;
1403 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1404 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1412 * early_platform_left - check if early platform driver has matching devices
1413 * @epdrv: early platform driver structure
1414 * @id: return true if id or above exists
1416 static int __init
early_platform_left(struct early_platform_driver
*epdrv
,
1419 struct platform_device
*pd
;
1421 list_for_each_entry(pd
, &early_platform_device_list
, dev
.devres_head
)
1422 if (platform_match(&pd
->dev
, &epdrv
->pdrv
->driver
))
1430 * early_platform_driver_probe_id - probe drivers matching class_str and id
1431 * @class_str: string to identify early platform driver class
1432 * @id: id to match against
1433 * @nr_probe: number of platform devices to successfully probe before exiting
1435 static int __init
early_platform_driver_probe_id(char *class_str
,
1439 struct early_platform_driver
*epdrv
;
1440 struct platform_device
*match
;
1445 list_for_each_entry(epdrv
, &early_platform_driver_list
, list
) {
1446 /* only use drivers matching our class_str */
1447 if (strcmp(class_str
, epdrv
->class_str
))
1451 match_id
= epdrv
->requested_id
;
1456 left
+= early_platform_left(epdrv
, id
);
1458 /* skip requested id */
1459 switch (epdrv
->requested_id
) {
1460 case EARLY_PLATFORM_ID_ERROR
:
1461 case EARLY_PLATFORM_ID_UNSET
:
1464 if (epdrv
->requested_id
== id
)
1465 match_id
= EARLY_PLATFORM_ID_UNSET
;
1470 case EARLY_PLATFORM_ID_ERROR
:
1471 pr_warn("%s: unable to parse %s parameter\n",
1472 class_str
, epdrv
->pdrv
->driver
.name
);
1474 case EARLY_PLATFORM_ID_UNSET
:
1478 match
= early_platform_match(epdrv
, match_id
);
1483 * Set up a sensible init_name to enable
1484 * dev_name() and others to be used before the
1485 * rest of the driver core is initialized.
1487 if (!match
->dev
.init_name
&& slab_is_available()) {
1488 if (match
->id
!= -1)
1489 match
->dev
.init_name
=
1490 kasprintf(GFP_KERNEL
, "%s.%d",
1494 match
->dev
.init_name
=
1495 kasprintf(GFP_KERNEL
, "%s",
1498 if (!match
->dev
.init_name
)
1502 if (epdrv
->pdrv
->probe(match
))
1503 pr_warn("%s: unable to probe %s early.\n",
1504 class_str
, match
->name
);
1520 * early_platform_driver_probe - probe a class of registered drivers
1521 * @class_str: string to identify early platform driver class
1522 * @nr_probe: number of platform devices to successfully probe before exiting
1523 * @user_only: only probe user specified early platform devices
1525 * Used by architecture code to probe registered early platform drivers
1526 * within a certain class. For probe to happen a registered early platform
1527 * device matching a registered early platform driver is needed.
1529 int __init
early_platform_driver_probe(char *class_str
,
1536 for (i
= -2; n
< nr_probe
; i
++) {
1537 k
= early_platform_driver_probe_id(class_str
, i
, nr_probe
- n
);
1552 * early_platform_cleanup - clean up early platform code
1554 void __init
early_platform_cleanup(void)
1556 struct platform_device
*pd
, *pd2
;
1558 /* clean up the devres list used to chain devices */
1559 list_for_each_entry_safe(pd
, pd2
, &early_platform_device_list
,
1561 list_del(&pd
->dev
.devres_head
);
1562 memset(&pd
->dev
.devres_head
, 0, sizeof(pd
->dev
.devres_head
));