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/platform_device.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/bootmem.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
23 #define to_platform_driver(drv) (container_of((drv), struct platform_driver, \
26 struct device platform_bus
= {
29 EXPORT_SYMBOL_GPL(platform_bus
);
32 * platform_get_resource - get a resource for a device
33 * @dev: platform device
34 * @type: resource type
35 * @num: resource index
37 struct resource
*platform_get_resource(struct platform_device
*dev
,
38 unsigned int type
, unsigned int num
)
42 for (i
= 0; i
< dev
->num_resources
; i
++) {
43 struct resource
*r
= &dev
->resource
[i
];
45 if ((r
->flags
& (IORESOURCE_IO
|IORESOURCE_MEM
|
46 IORESOURCE_IRQ
|IORESOURCE_DMA
)) == type
)
52 EXPORT_SYMBOL_GPL(platform_get_resource
);
55 * platform_get_irq - get an IRQ for a device
56 * @dev: platform device
57 * @num: IRQ number index
59 int platform_get_irq(struct platform_device
*dev
, unsigned int num
)
61 struct resource
*r
= platform_get_resource(dev
, IORESOURCE_IRQ
, num
);
63 return r
? r
->start
: -ENXIO
;
65 EXPORT_SYMBOL_GPL(platform_get_irq
);
68 * platform_get_resource_byname - get a resource for a device by name
69 * @dev: platform device
70 * @type: resource type
71 * @name: resource name
73 struct resource
*platform_get_resource_byname(struct platform_device
*dev
,
74 unsigned int type
, char *name
)
78 for (i
= 0; i
< dev
->num_resources
; i
++) {
79 struct resource
*r
= &dev
->resource
[i
];
81 if ((r
->flags
& (IORESOURCE_IO
|IORESOURCE_MEM
|
82 IORESOURCE_IRQ
|IORESOURCE_DMA
)) == type
)
83 if (!strcmp(r
->name
, name
))
88 EXPORT_SYMBOL_GPL(platform_get_resource_byname
);
91 * platform_get_irq - get an IRQ for a device
92 * @dev: platform device
95 int platform_get_irq_byname(struct platform_device
*dev
, char *name
)
97 struct resource
*r
= platform_get_resource_byname(dev
, IORESOURCE_IRQ
,
100 return r
? r
->start
: -ENXIO
;
102 EXPORT_SYMBOL_GPL(platform_get_irq_byname
);
105 * platform_add_devices - add a numbers of platform devices
106 * @devs: array of platform devices to add
107 * @num: number of platform devices in array
109 int platform_add_devices(struct platform_device
**devs
, int num
)
113 for (i
= 0; i
< num
; i
++) {
114 ret
= platform_device_register(devs
[i
]);
117 platform_device_unregister(devs
[i
]);
124 EXPORT_SYMBOL_GPL(platform_add_devices
);
126 struct platform_object
{
127 struct platform_device pdev
;
132 * platform_device_put
133 * @pdev: platform device to free
135 * Free all memory associated with a platform device. This function must
136 * _only_ be externally called in error cases. All other usage is a bug.
138 void platform_device_put(struct platform_device
*pdev
)
141 put_device(&pdev
->dev
);
143 EXPORT_SYMBOL_GPL(platform_device_put
);
145 static void platform_device_release(struct device
*dev
)
147 struct platform_object
*pa
= container_of(dev
, struct platform_object
,
150 kfree(pa
->pdev
.dev
.platform_data
);
151 kfree(pa
->pdev
.resource
);
156 * platform_device_alloc
157 * @name: base name of the device we're adding
160 * Create a platform device object which can have other objects attached
161 * to it, and which will have attached objects freed when it is released.
163 struct platform_device
*platform_device_alloc(const char *name
, int id
)
165 struct platform_object
*pa
;
167 pa
= kzalloc(sizeof(struct platform_object
) + strlen(name
), GFP_KERNEL
);
169 strcpy(pa
->name
, name
);
170 pa
->pdev
.name
= pa
->name
;
172 device_initialize(&pa
->pdev
.dev
);
173 pa
->pdev
.dev
.release
= platform_device_release
;
176 return pa
? &pa
->pdev
: NULL
;
178 EXPORT_SYMBOL_GPL(platform_device_alloc
);
181 * platform_device_add_resources
182 * @pdev: platform device allocated by platform_device_alloc to add resources to
183 * @res: set of resources that needs to be allocated for the device
184 * @num: number of resources
186 * Add a copy of the resources to the platform device. The memory
187 * associated with the resources will be freed when the platform device is
190 int platform_device_add_resources(struct platform_device
*pdev
,
191 struct resource
*res
, unsigned int num
)
195 r
= kmalloc(sizeof(struct resource
) * num
, GFP_KERNEL
);
197 memcpy(r
, res
, sizeof(struct resource
) * num
);
199 pdev
->num_resources
= num
;
201 return r
? 0 : -ENOMEM
;
203 EXPORT_SYMBOL_GPL(platform_device_add_resources
);
206 * platform_device_add_data
207 * @pdev: platform device allocated by platform_device_alloc to add resources to
208 * @data: platform specific data for this platform device
209 * @size: size of platform specific data
211 * Add a copy of platform specific data to the platform device's
212 * platform_data pointer. The memory associated with the platform data
213 * will be freed when the platform device is released.
215 int platform_device_add_data(struct platform_device
*pdev
, const void *data
,
220 d
= kmalloc(size
, GFP_KERNEL
);
222 memcpy(d
, data
, size
);
223 pdev
->dev
.platform_data
= d
;
225 return d
? 0 : -ENOMEM
;
227 EXPORT_SYMBOL_GPL(platform_device_add_data
);
230 * platform_device_add - add a platform device to device hierarchy
231 * @pdev: platform device we're adding
233 * This is part 2 of platform_device_register(), though may be called
234 * separately _iff_ pdev was allocated by platform_device_alloc().
236 int platform_device_add(struct platform_device
*pdev
)
243 if (!pdev
->dev
.parent
)
244 pdev
->dev
.parent
= &platform_bus
;
246 pdev
->dev
.bus
= &platform_bus_type
;
249 snprintf(pdev
->dev
.bus_id
, BUS_ID_SIZE
, "%s.%d", pdev
->name
,
252 strlcpy(pdev
->dev
.bus_id
, pdev
->name
, BUS_ID_SIZE
);
254 for (i
= 0; i
< pdev
->num_resources
; i
++) {
255 struct resource
*p
, *r
= &pdev
->resource
[i
];
258 r
->name
= pdev
->dev
.bus_id
;
262 if (r
->flags
& IORESOURCE_MEM
)
264 else if (r
->flags
& IORESOURCE_IO
)
265 p
= &ioport_resource
;
268 if (p
&& insert_resource(p
, r
)) {
270 "%s: failed to claim resource %d\n",
271 pdev
->dev
.bus_id
, i
);
277 pr_debug("Registering platform device '%s'. Parent at %s\n",
278 pdev
->dev
.bus_id
, pdev
->dev
.parent
->bus_id
);
280 ret
= device_add(&pdev
->dev
);
286 if (pdev
->resource
[i
].flags
& (IORESOURCE_MEM
|IORESOURCE_IO
))
287 release_resource(&pdev
->resource
[i
]);
290 EXPORT_SYMBOL_GPL(platform_device_add
);
293 * platform_device_del - remove a platform-level device
294 * @pdev: platform device we're removing
296 * Note that this function will also release all memory- and port-based
297 * resources owned by the device (@dev->resource). This function must
298 * _only_ be externally called in error cases. All other usage is a bug.
300 void platform_device_del(struct platform_device
*pdev
)
305 device_del(&pdev
->dev
);
307 for (i
= 0; i
< pdev
->num_resources
; i
++) {
308 struct resource
*r
= &pdev
->resource
[i
];
309 if (r
->flags
& (IORESOURCE_MEM
|IORESOURCE_IO
))
314 EXPORT_SYMBOL_GPL(platform_device_del
);
317 * platform_device_register - add a platform-level device
318 * @pdev: platform device we're adding
320 int platform_device_register(struct platform_device
*pdev
)
322 device_initialize(&pdev
->dev
);
323 return platform_device_add(pdev
);
325 EXPORT_SYMBOL_GPL(platform_device_register
);
328 * platform_device_unregister - unregister a platform-level device
329 * @pdev: platform device we're unregistering
331 * Unregistration is done in 2 steps. First we release all resources
332 * and remove it from the subsystem, then we drop reference count by
333 * calling platform_device_put().
335 void platform_device_unregister(struct platform_device
*pdev
)
337 platform_device_del(pdev
);
338 platform_device_put(pdev
);
340 EXPORT_SYMBOL_GPL(platform_device_unregister
);
343 * platform_device_register_simple
344 * @name: base name of the device we're adding
346 * @res: set of resources that needs to be allocated for the device
347 * @num: number of resources
349 * This function creates a simple platform device that requires minimal
350 * resource and memory management. Canned release function freeing memory
351 * allocated for the device allows drivers using such devices to be
352 * unloaded without waiting for the last reference to the device to be
355 * This interface is primarily intended for use with legacy drivers which
356 * probe hardware directly. Because such drivers create sysfs device nodes
357 * themselves, rather than letting system infrastructure handle such device
358 * enumeration tasks, they don't fully conform to the Linux driver model.
359 * In particular, when such drivers are built as modules, they can't be
362 struct platform_device
*platform_device_register_simple(const char *name
,
364 struct resource
*res
,
367 struct platform_device
*pdev
;
370 pdev
= platform_device_alloc(name
, id
);
377 retval
= platform_device_add_resources(pdev
, res
, num
);
382 retval
= platform_device_add(pdev
);
389 platform_device_put(pdev
);
390 return ERR_PTR(retval
);
392 EXPORT_SYMBOL_GPL(platform_device_register_simple
);
394 static int platform_drv_probe(struct device
*_dev
)
396 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
397 struct platform_device
*dev
= to_platform_device(_dev
);
399 return drv
->probe(dev
);
402 static int platform_drv_probe_fail(struct device
*_dev
)
407 static int platform_drv_remove(struct device
*_dev
)
409 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
410 struct platform_device
*dev
= to_platform_device(_dev
);
412 return drv
->remove(dev
);
415 static void platform_drv_shutdown(struct device
*_dev
)
417 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
418 struct platform_device
*dev
= to_platform_device(_dev
);
423 static int platform_drv_suspend(struct device
*_dev
, pm_message_t state
)
425 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
426 struct platform_device
*dev
= to_platform_device(_dev
);
428 return drv
->suspend(dev
, state
);
431 static int platform_drv_resume(struct device
*_dev
)
433 struct platform_driver
*drv
= to_platform_driver(_dev
->driver
);
434 struct platform_device
*dev
= to_platform_device(_dev
);
436 return drv
->resume(dev
);
440 * platform_driver_register
441 * @drv: platform driver structure
443 int platform_driver_register(struct platform_driver
*drv
)
445 drv
->driver
.bus
= &platform_bus_type
;
447 drv
->driver
.probe
= platform_drv_probe
;
449 drv
->driver
.remove
= platform_drv_remove
;
451 drv
->driver
.shutdown
= platform_drv_shutdown
;
453 drv
->driver
.suspend
= platform_drv_suspend
;
455 drv
->driver
.resume
= platform_drv_resume
;
456 return driver_register(&drv
->driver
);
458 EXPORT_SYMBOL_GPL(platform_driver_register
);
461 * platform_driver_unregister
462 * @drv: platform driver structure
464 void platform_driver_unregister(struct platform_driver
*drv
)
466 driver_unregister(&drv
->driver
);
468 EXPORT_SYMBOL_GPL(platform_driver_unregister
);
471 * platform_driver_probe - register driver for non-hotpluggable device
472 * @drv: platform driver structure
473 * @probe: the driver probe routine, probably from an __init section
475 * Use this instead of platform_driver_register() when you know the device
476 * is not hotpluggable and has already been registered, and you want to
477 * remove its run-once probe() infrastructure from memory after the driver
478 * has bound to the device.
480 * One typical use for this would be with drivers for controllers integrated
481 * into system-on-chip processors, where the controller devices have been
482 * configured as part of board setup.
484 * Returns zero if the driver registered and bound to a device, else returns
485 * a negative error code and with the driver not registered.
487 int __init_or_module
platform_driver_probe(struct platform_driver
*drv
,
488 int (*probe
)(struct platform_device
*))
492 /* temporary section violation during probe() */
494 retval
= code
= platform_driver_register(drv
);
496 /* Fixup that section violation, being paranoid about code scanning
497 * the list of drivers in order to probe new devices. Check to see
498 * if the probe was successful, and make sure any forced probes of
501 spin_lock(&platform_bus_type
.p
->klist_drivers
.k_lock
);
503 if (code
== 0 && list_empty(&drv
->driver
.p
->klist_devices
.k_list
))
505 drv
->driver
.probe
= platform_drv_probe_fail
;
506 spin_unlock(&platform_bus_type
.p
->klist_drivers
.k_lock
);
509 platform_driver_unregister(drv
);
512 EXPORT_SYMBOL_GPL(platform_driver_probe
);
514 /* modalias support enables more hands-off userspace setup:
515 * (a) environment variable lets new-style hotplug events work once system is
516 * fully running: "modprobe $MODALIAS"
517 * (b) sysfs attribute lets new-style coldplug recover from hotplug events
518 * mishandled before system is fully running: "modprobe $(cat modalias)"
520 static ssize_t
modalias_show(struct device
*dev
, struct device_attribute
*a
,
523 struct platform_device
*pdev
= to_platform_device(dev
);
524 int len
= snprintf(buf
, PAGE_SIZE
, "platform:%s\n", pdev
->name
);
526 return (len
>= PAGE_SIZE
) ? (PAGE_SIZE
- 1) : len
;
529 static struct device_attribute platform_dev_attrs
[] = {
534 static int platform_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
536 struct platform_device
*pdev
= to_platform_device(dev
);
538 add_uevent_var(env
, "MODALIAS=platform:%s", pdev
->name
);
543 * platform_match - bind platform device to platform driver.
547 * Platform device IDs are assumed to be encoded like this:
548 * "<name><instance>", where <name> is a short description of the type of
549 * device, like "pci" or "floppy", and <instance> is the enumerated
550 * instance of the device, like '0' or '42'. Driver IDs are simply
551 * "<name>". So, extract the <name> from the platform_device structure,
552 * and compare it against the name of the driver. Return whether they match
555 static int platform_match(struct device
*dev
, struct device_driver
*drv
)
557 struct platform_device
*pdev
;
559 pdev
= container_of(dev
, struct platform_device
, dev
);
560 return (strncmp(pdev
->name
, drv
->name
, BUS_ID_SIZE
) == 0);
563 static int platform_suspend(struct device
*dev
, pm_message_t mesg
)
567 if (dev
->driver
&& dev
->driver
->suspend
)
568 ret
= dev
->driver
->suspend(dev
, mesg
);
573 static int platform_suspend_late(struct device
*dev
, pm_message_t mesg
)
575 struct platform_driver
*drv
= to_platform_driver(dev
->driver
);
576 struct platform_device
*pdev
;
579 pdev
= container_of(dev
, struct platform_device
, dev
);
580 if (dev
->driver
&& drv
->suspend_late
)
581 ret
= drv
->suspend_late(pdev
, mesg
);
586 static int platform_resume_early(struct device
*dev
)
588 struct platform_driver
*drv
= to_platform_driver(dev
->driver
);
589 struct platform_device
*pdev
;
592 pdev
= container_of(dev
, struct platform_device
, dev
);
593 if (dev
->driver
&& drv
->resume_early
)
594 ret
= drv
->resume_early(pdev
);
599 static int platform_resume(struct device
*dev
)
603 if (dev
->driver
&& dev
->driver
->resume
)
604 ret
= dev
->driver
->resume(dev
);
609 struct bus_type platform_bus_type
= {
611 .dev_attrs
= platform_dev_attrs
,
612 .match
= platform_match
,
613 .uevent
= platform_uevent
,
614 .suspend
= platform_suspend
,
615 .suspend_late
= platform_suspend_late
,
616 .resume_early
= platform_resume_early
,
617 .resume
= platform_resume
,
619 EXPORT_SYMBOL_GPL(platform_bus_type
);
621 int __init
platform_bus_init(void)
625 error
= device_register(&platform_bus
);
628 error
= bus_register(&platform_bus_type
);
630 device_unregister(&platform_bus
);
634 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
635 u64
dma_get_required_mask(struct device
*dev
)
637 u32 low_totalram
= ((max_pfn
- 1) << PAGE_SHIFT
);
638 u32 high_totalram
= ((max_pfn
- 1) >> (32 - PAGE_SHIFT
));
641 if (!high_totalram
) {
642 /* convert to mask just covering totalram */
643 low_totalram
= (1 << (fls(low_totalram
) - 1));
644 low_totalram
+= low_totalram
- 1;
647 high_totalram
= (1 << (fls(high_totalram
) - 1));
648 high_totalram
+= high_totalram
- 1;
649 mask
= (((u64
)high_totalram
) << 32) + 0xffffffff;
651 return mask
& *dev
->dma_mask
;
653 EXPORT_SYMBOL_GPL(dma_get_required_mask
);