2 * linux/arch/arm/common/amba.c
4 * Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/device.h>
13 #include <linux/string.h>
14 #include <linux/slab.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/amba/bus.h>
21 #include <asm/sizes.h>
23 #define to_amba_driver(d) container_of(d, struct amba_driver, drv)
25 static const struct amba_id
*
26 amba_lookup(const struct amba_id
*table
, struct amba_device
*dev
)
31 ret
= (dev
->periphid
& table
->mask
) == table
->id
;
37 return ret
? table
: NULL
;
40 static int amba_match(struct device
*dev
, struct device_driver
*drv
)
42 struct amba_device
*pcdev
= to_amba_device(dev
);
43 struct amba_driver
*pcdrv
= to_amba_driver(drv
);
45 return amba_lookup(pcdrv
->id_table
, pcdev
) != NULL
;
49 static int amba_uevent(struct device
*dev
, struct kobj_uevent_env
*env
)
51 struct amba_device
*pcdev
= to_amba_device(dev
);
54 retval
= add_uevent_var(env
, "AMBA_ID=%08x", pcdev
->periphid
);
58 retval
= add_uevent_var(env
, "MODALIAS=amba:d%08X", pcdev
->periphid
);
62 #define amba_uevent NULL
65 #define amba_attr_func(name,fmt,arg...) \
66 static ssize_t name##_show(struct device *_dev, \
67 struct device_attribute *attr, char *buf) \
69 struct amba_device *dev = to_amba_device(_dev); \
70 return sprintf(buf, fmt, arg); \
73 #define amba_attr(name,fmt,arg...) \
74 amba_attr_func(name,fmt,arg) \
75 static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
77 amba_attr_func(id
, "%08x\n", dev
->periphid
);
78 amba_attr(irq0
, "%u\n", dev
->irq
[0]);
79 amba_attr(irq1
, "%u\n", dev
->irq
[1]);
80 amba_attr_func(resource
, "\t%016llx\t%016llx\t%016lx\n",
81 (unsigned long long)dev
->res
.start
, (unsigned long long)dev
->res
.end
,
84 static struct device_attribute amba_dev_attrs
[] = {
90 #ifdef CONFIG_PM_SLEEP
92 static int amba_legacy_suspend(struct device
*dev
, pm_message_t mesg
)
94 struct amba_driver
*adrv
= to_amba_driver(dev
->driver
);
95 struct amba_device
*adev
= to_amba_device(dev
);
98 if (dev
->driver
&& adrv
->suspend
)
99 ret
= adrv
->suspend(adev
, mesg
);
104 static int amba_legacy_resume(struct device
*dev
)
106 struct amba_driver
*adrv
= to_amba_driver(dev
->driver
);
107 struct amba_device
*adev
= to_amba_device(dev
);
110 if (dev
->driver
&& adrv
->resume
)
111 ret
= adrv
->resume(adev
);
116 #endif /* CONFIG_PM_SLEEP */
118 #ifdef CONFIG_SUSPEND
120 static int amba_pm_suspend(struct device
*dev
)
122 struct device_driver
*drv
= dev
->driver
;
129 if (drv
->pm
->suspend
)
130 ret
= drv
->pm
->suspend(dev
);
132 ret
= amba_legacy_suspend(dev
, PMSG_SUSPEND
);
138 static int amba_pm_resume(struct device
*dev
)
140 struct device_driver
*drv
= dev
->driver
;
148 ret
= drv
->pm
->resume(dev
);
150 ret
= amba_legacy_resume(dev
);
156 #else /* !CONFIG_SUSPEND */
158 #define amba_pm_suspend NULL
159 #define amba_pm_resume NULL
161 #endif /* !CONFIG_SUSPEND */
163 #ifdef CONFIG_HIBERNATE_CALLBACKS
165 static int amba_pm_freeze(struct device
*dev
)
167 struct device_driver
*drv
= dev
->driver
;
175 ret
= drv
->pm
->freeze(dev
);
177 ret
= amba_legacy_suspend(dev
, PMSG_FREEZE
);
183 static int amba_pm_thaw(struct device
*dev
)
185 struct device_driver
*drv
= dev
->driver
;
193 ret
= drv
->pm
->thaw(dev
);
195 ret
= amba_legacy_resume(dev
);
201 static int amba_pm_poweroff(struct device
*dev
)
203 struct device_driver
*drv
= dev
->driver
;
210 if (drv
->pm
->poweroff
)
211 ret
= drv
->pm
->poweroff(dev
);
213 ret
= amba_legacy_suspend(dev
, PMSG_HIBERNATE
);
219 static int amba_pm_restore(struct device
*dev
)
221 struct device_driver
*drv
= dev
->driver
;
228 if (drv
->pm
->restore
)
229 ret
= drv
->pm
->restore(dev
);
231 ret
= amba_legacy_resume(dev
);
237 #else /* !CONFIG_HIBERNATE_CALLBACKS */
239 #define amba_pm_freeze NULL
240 #define amba_pm_thaw NULL
241 #define amba_pm_poweroff NULL
242 #define amba_pm_restore NULL
244 #endif /* !CONFIG_HIBERNATE_CALLBACKS */
246 #ifdef CONFIG_PM_RUNTIME
248 * Hooks to provide runtime PM of the pclk (bus clock). It is safe to
249 * enable/disable the bus clock at runtime PM suspend/resume as this
250 * does not result in loss of context.
252 static int amba_pm_runtime_suspend(struct device
*dev
)
254 struct amba_device
*pcdev
= to_amba_device(dev
);
255 int ret
= pm_generic_runtime_suspend(dev
);
257 if (ret
== 0 && dev
->driver
)
258 clk_disable(pcdev
->pclk
);
263 static int amba_pm_runtime_resume(struct device
*dev
)
265 struct amba_device
*pcdev
= to_amba_device(dev
);
269 ret
= clk_enable(pcdev
->pclk
);
270 /* Failure is probably fatal to the system, but... */
275 return pm_generic_runtime_resume(dev
);
281 static const struct dev_pm_ops amba_pm
= {
282 .suspend
= amba_pm_suspend
,
283 .resume
= amba_pm_resume
,
284 .freeze
= amba_pm_freeze
,
285 .thaw
= amba_pm_thaw
,
286 .poweroff
= amba_pm_poweroff
,
287 .restore
= amba_pm_restore
,
289 amba_pm_runtime_suspend
,
290 amba_pm_runtime_resume
,
291 pm_generic_runtime_idle
295 #define AMBA_PM (&amba_pm)
297 #else /* !CONFIG_PM */
301 #endif /* !CONFIG_PM */
304 * Primecells are part of the Advanced Microcontroller Bus Architecture,
305 * so we call the bus "amba".
307 struct bus_type amba_bustype
= {
309 .dev_attrs
= amba_dev_attrs
,
311 .uevent
= amba_uevent
,
315 static int __init
amba_init(void)
317 return bus_register(&amba_bustype
);
320 postcore_initcall(amba_init
);
322 static int amba_get_enable_pclk(struct amba_device
*pcdev
)
324 struct clk
*pclk
= clk_get(&pcdev
->dev
, "apb_pclk");
330 return PTR_ERR(pclk
);
332 ret
= clk_prepare(pclk
);
338 ret
= clk_enable(pclk
);
347 static void amba_put_disable_pclk(struct amba_device
*pcdev
)
349 struct clk
*pclk
= pcdev
->pclk
;
357 * These are the device model conversion veneers; they convert the
358 * device model structures to our more specific structures.
360 static int amba_probe(struct device
*dev
)
362 struct amba_device
*pcdev
= to_amba_device(dev
);
363 struct amba_driver
*pcdrv
= to_amba_driver(dev
->driver
);
364 const struct amba_id
*id
= amba_lookup(pcdrv
->id_table
, pcdev
);
368 ret
= amba_get_enable_pclk(pcdev
);
372 pm_runtime_get_noresume(dev
);
373 pm_runtime_set_active(dev
);
374 pm_runtime_enable(dev
);
376 ret
= pcdrv
->probe(pcdev
, id
);
380 pm_runtime_disable(dev
);
381 pm_runtime_set_suspended(dev
);
382 pm_runtime_put_noidle(dev
);
384 amba_put_disable_pclk(pcdev
);
390 static int amba_remove(struct device
*dev
)
392 struct amba_device
*pcdev
= to_amba_device(dev
);
393 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
396 pm_runtime_get_sync(dev
);
397 ret
= drv
->remove(pcdev
);
398 pm_runtime_put_noidle(dev
);
400 /* Undo the runtime PM settings in amba_probe() */
401 pm_runtime_disable(dev
);
402 pm_runtime_set_suspended(dev
);
403 pm_runtime_put_noidle(dev
);
405 amba_put_disable_pclk(pcdev
);
410 static void amba_shutdown(struct device
*dev
)
412 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
413 drv
->shutdown(to_amba_device(dev
));
417 * amba_driver_register - register an AMBA device driver
418 * @drv: amba device driver structure
420 * Register an AMBA device driver with the Linux device model
421 * core. If devices pre-exist, the drivers probe function will
424 int amba_driver_register(struct amba_driver
*drv
)
426 drv
->drv
.bus
= &amba_bustype
;
428 #define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
433 return driver_register(&drv
->drv
);
437 * amba_driver_unregister - remove an AMBA device driver
438 * @drv: AMBA device driver structure to remove
440 * Unregister an AMBA device driver from the Linux device
441 * model. The device model will call the drivers remove function
442 * for each device the device driver is currently handling.
444 void amba_driver_unregister(struct amba_driver
*drv
)
446 driver_unregister(&drv
->drv
);
450 static void amba_device_release(struct device
*dev
)
452 struct amba_device
*d
= to_amba_device(dev
);
455 release_resource(&d
->res
);
460 * amba_device_add - add a previously allocated AMBA device structure
461 * @dev: AMBA device allocated by amba_device_alloc
462 * @parent: resource parent for this devices resources
464 * Claim the resource, and read the device cell ID if not already
465 * initialized. Register the AMBA device with the Linux device
468 int amba_device_add(struct amba_device
*dev
, struct resource
*parent
)
474 WARN_ON(dev
->irq
[0] == (unsigned int)-1);
475 WARN_ON(dev
->irq
[1] == (unsigned int)-1);
477 ret
= request_resource(parent
, &dev
->res
);
481 /* Hard-coded primecell ID instead of plug-n-play */
482 if (dev
->periphid
!= 0)
486 * Dynamically calculate the size of the resource
487 * and use this for iomap
489 size
= resource_size(&dev
->res
);
490 tmp
= ioremap(dev
->res
.start
, size
);
496 ret
= amba_get_enable_pclk(dev
);
501 * Read pid and cid based on size of resource
502 * they are located at end of region
504 for (pid
= 0, i
= 0; i
< 4; i
++)
505 pid
|= (readl(tmp
+ size
- 0x20 + 4 * i
) & 255) <<
507 for (cid
= 0, i
= 0; i
< 4; i
++)
508 cid
|= (readl(tmp
+ size
- 0x10 + 4 * i
) & 255) <<
511 amba_put_disable_pclk(dev
);
526 ret
= device_add(&dev
->dev
);
530 if (dev
->irq
[0] && dev
->irq
[0] != NO_IRQ
)
531 ret
= device_create_file(&dev
->dev
, &dev_attr_irq0
);
532 if (ret
== 0 && dev
->irq
[1] && dev
->irq
[1] != NO_IRQ
)
533 ret
= device_create_file(&dev
->dev
, &dev_attr_irq1
);
537 device_unregister(&dev
->dev
);
540 release_resource(&dev
->res
);
544 EXPORT_SYMBOL_GPL(amba_device_add
);
546 static void amba_device_initialize(struct amba_device
*dev
, const char *name
)
548 device_initialize(&dev
->dev
);
550 dev_set_name(&dev
->dev
, "%s", name
);
551 dev
->dev
.release
= amba_device_release
;
552 dev
->dev
.bus
= &amba_bustype
;
553 dev
->dev
.dma_mask
= &dev
->dma_mask
;
554 dev
->res
.name
= dev_name(&dev
->dev
);
558 * amba_device_alloc - allocate an AMBA device
559 * @name: sysfs name of the AMBA device
560 * @base: base of AMBA device
561 * @size: size of AMBA device
563 * Allocate and initialize an AMBA device structure. Returns %NULL
566 struct amba_device
*amba_device_alloc(const char *name
, resource_size_t base
,
569 struct amba_device
*dev
;
571 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
573 amba_device_initialize(dev
, name
);
574 dev
->res
.start
= base
;
575 dev
->res
.end
= base
+ size
- 1;
576 dev
->res
.flags
= IORESOURCE_MEM
;
581 EXPORT_SYMBOL_GPL(amba_device_alloc
);
584 * amba_device_register - register an AMBA device
585 * @dev: AMBA device to register
586 * @parent: parent memory resource
588 * Setup the AMBA device, reading the cell ID if present.
589 * Claim the resource, and register the AMBA device with
590 * the Linux device manager.
592 int amba_device_register(struct amba_device
*dev
, struct resource
*parent
)
594 amba_device_initialize(dev
, dev
->dev
.init_name
);
595 dev
->dev
.init_name
= NULL
;
597 if (!dev
->dev
.coherent_dma_mask
&& dev
->dma_mask
)
598 dev_warn(&dev
->dev
, "coherent dma mask is unset\n");
600 return amba_device_add(dev
, parent
);
604 * amba_device_put - put an AMBA device
605 * @dev: AMBA device to put
607 void amba_device_put(struct amba_device
*dev
)
609 put_device(&dev
->dev
);
611 EXPORT_SYMBOL_GPL(amba_device_put
);
614 * amba_device_unregister - unregister an AMBA device
615 * @dev: AMBA device to remove
617 * Remove the specified AMBA device from the Linux device
618 * manager. All files associated with this object will be
619 * destroyed, and device drivers notified that the device has
620 * been removed. The AMBA device's resources including
621 * the amba_device structure will be freed once all
622 * references to it have been dropped.
624 void amba_device_unregister(struct amba_device
*dev
)
626 device_unregister(&dev
->dev
);
631 struct amba_device
*dev
;
632 struct device
*parent
;
638 static int amba_find_match(struct device
*dev
, void *data
)
640 struct find_data
*d
= data
;
641 struct amba_device
*pcdev
= to_amba_device(dev
);
644 r
= (pcdev
->periphid
& d
->mask
) == d
->id
;
646 r
&= d
->parent
== dev
->parent
;
648 r
&= strcmp(dev_name(dev
), d
->busid
) == 0;
659 * amba_find_device - locate an AMBA device given a bus id
660 * @busid: bus id for device (or NULL)
661 * @parent: parent device (or NULL)
662 * @id: peripheral ID (or 0)
663 * @mask: peripheral ID mask (or 0)
665 * Return the AMBA device corresponding to the supplied parameters.
666 * If no device matches, returns NULL.
668 * NOTE: When a valid device is found, its refcount is
669 * incremented, and must be decremented before the returned
673 amba_find_device(const char *busid
, struct device
*parent
, unsigned int id
,
676 struct find_data data
;
679 data
.parent
= parent
;
684 bus_for_each_dev(&amba_bustype
, NULL
, &data
, amba_find_match
);
690 * amba_request_regions - request all mem regions associated with device
691 * @dev: amba_device structure for device
692 * @name: name, or NULL to use driver name
694 int amba_request_regions(struct amba_device
*dev
, const char *name
)
700 name
= dev
->dev
.driver
->name
;
702 size
= resource_size(&dev
->res
);
704 if (!request_mem_region(dev
->res
.start
, size
, name
))
711 * amba_release_regions - release mem regions associated with device
712 * @dev: amba_device structure for device
714 * Release regions claimed by a successful call to amba_request_regions.
716 void amba_release_regions(struct amba_device
*dev
)
720 size
= resource_size(&dev
->res
);
721 release_mem_region(dev
->res
.start
, size
);
724 EXPORT_SYMBOL(amba_driver_register
);
725 EXPORT_SYMBOL(amba_driver_unregister
);
726 EXPORT_SYMBOL(amba_device_register
);
727 EXPORT_SYMBOL(amba_device_unregister
);
728 EXPORT_SYMBOL(amba_find_device
);
729 EXPORT_SYMBOL(amba_request_regions
);
730 EXPORT_SYMBOL(amba_release_regions
);