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/pm_domain.h>
19 #include <linux/amba/bus.h>
20 #include <linux/sizes.h>
24 #define to_amba_driver(d) container_of(d, struct amba_driver, drv)
26 static const struct amba_id
*
27 amba_lookup(const struct amba_id
*table
, struct amba_device
*dev
)
32 ret
= (dev
->periphid
& table
->mask
) == table
->id
;
38 return ret
? table
: NULL
;
41 static int amba_match(struct device
*dev
, struct device_driver
*drv
)
43 struct amba_device
*pcdev
= to_amba_device(dev
);
44 struct amba_driver
*pcdrv
= to_amba_driver(drv
);
46 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_attr_func(name,fmt,arg...) \
63 static ssize_t name##_show(struct device *_dev, \
64 struct device_attribute *attr, char *buf) \
66 struct amba_device *dev = to_amba_device(_dev); \
67 return sprintf(buf, fmt, arg); \
70 #define amba_attr(name,fmt,arg...) \
71 amba_attr_func(name,fmt,arg) \
72 static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
74 amba_attr_func(id
, "%08x\n", dev
->periphid
);
75 amba_attr(irq0
, "%u\n", dev
->irq
[0]);
76 amba_attr(irq1
, "%u\n", dev
->irq
[1]);
77 amba_attr_func(resource
, "\t%016llx\t%016llx\t%016lx\n",
78 (unsigned long long)dev
->res
.start
, (unsigned long long)dev
->res
.end
,
81 static struct device_attribute amba_dev_attrs
[] = {
89 * Hooks to provide runtime PM of the pclk (bus clock). It is safe to
90 * enable/disable the bus clock at runtime PM suspend/resume as this
91 * does not result in loss of context.
93 static int amba_pm_runtime_suspend(struct device
*dev
)
95 struct amba_device
*pcdev
= to_amba_device(dev
);
96 int ret
= pm_generic_runtime_suspend(dev
);
98 if (ret
== 0 && dev
->driver
)
99 clk_disable_unprepare(pcdev
->pclk
);
104 static int amba_pm_runtime_resume(struct device
*dev
)
106 struct amba_device
*pcdev
= to_amba_device(dev
);
110 ret
= clk_prepare_enable(pcdev
->pclk
);
111 /* Failure is probably fatal to the system, but... */
116 return pm_generic_runtime_resume(dev
);
120 static const struct dev_pm_ops amba_pm
= {
121 .suspend
= pm_generic_suspend
,
122 .resume
= pm_generic_resume
,
123 .freeze
= pm_generic_freeze
,
124 .thaw
= pm_generic_thaw
,
125 .poweroff
= pm_generic_poweroff
,
126 .restore
= pm_generic_restore
,
128 amba_pm_runtime_suspend
,
129 amba_pm_runtime_resume
,
135 * Primecells are part of the Advanced Microcontroller Bus Architecture,
136 * so we call the bus "amba".
138 struct bus_type amba_bustype
= {
140 .dev_attrs
= amba_dev_attrs
,
142 .uevent
= amba_uevent
,
146 static int __init
amba_init(void)
148 return bus_register(&amba_bustype
);
151 postcore_initcall(amba_init
);
153 static int amba_get_enable_pclk(struct amba_device
*pcdev
)
157 pcdev
->pclk
= clk_get(&pcdev
->dev
, "apb_pclk");
158 if (IS_ERR(pcdev
->pclk
))
159 return PTR_ERR(pcdev
->pclk
);
161 ret
= clk_prepare_enable(pcdev
->pclk
);
163 clk_put(pcdev
->pclk
);
168 static void amba_put_disable_pclk(struct amba_device
*pcdev
)
170 clk_disable_unprepare(pcdev
->pclk
);
171 clk_put(pcdev
->pclk
);
175 * These are the device model conversion veneers; they convert the
176 * device model structures to our more specific structures.
178 static int amba_probe(struct device
*dev
)
180 struct amba_device
*pcdev
= to_amba_device(dev
);
181 struct amba_driver
*pcdrv
= to_amba_driver(dev
->driver
);
182 const struct amba_id
*id
= amba_lookup(pcdrv
->id_table
, pcdev
);
186 ret
= dev_pm_domain_attach(dev
, true);
187 if (ret
== -EPROBE_DEFER
)
190 ret
= amba_get_enable_pclk(pcdev
);
192 dev_pm_domain_detach(dev
, true);
196 pm_runtime_get_noresume(dev
);
197 pm_runtime_set_active(dev
);
198 pm_runtime_enable(dev
);
200 ret
= pcdrv
->probe(pcdev
, id
);
204 pm_runtime_disable(dev
);
205 pm_runtime_set_suspended(dev
);
206 pm_runtime_put_noidle(dev
);
208 amba_put_disable_pclk(pcdev
);
209 dev_pm_domain_detach(dev
, true);
215 static int amba_remove(struct device
*dev
)
217 struct amba_device
*pcdev
= to_amba_device(dev
);
218 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
221 pm_runtime_get_sync(dev
);
222 ret
= drv
->remove(pcdev
);
223 pm_runtime_put_noidle(dev
);
225 /* Undo the runtime PM settings in amba_probe() */
226 pm_runtime_disable(dev
);
227 pm_runtime_set_suspended(dev
);
228 pm_runtime_put_noidle(dev
);
230 amba_put_disable_pclk(pcdev
);
231 dev_pm_domain_detach(dev
, true);
236 static void amba_shutdown(struct device
*dev
)
238 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
239 drv
->shutdown(to_amba_device(dev
));
243 * amba_driver_register - register an AMBA device driver
244 * @drv: amba device driver structure
246 * Register an AMBA device driver with the Linux device model
247 * core. If devices pre-exist, the drivers probe function will
250 int amba_driver_register(struct amba_driver
*drv
)
252 drv
->drv
.bus
= &amba_bustype
;
254 #define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
259 return driver_register(&drv
->drv
);
263 * amba_driver_unregister - remove an AMBA device driver
264 * @drv: AMBA device driver structure to remove
266 * Unregister an AMBA device driver from the Linux device
267 * model. The device model will call the drivers remove function
268 * for each device the device driver is currently handling.
270 void amba_driver_unregister(struct amba_driver
*drv
)
272 driver_unregister(&drv
->drv
);
276 static void amba_device_release(struct device
*dev
)
278 struct amba_device
*d
= to_amba_device(dev
);
281 release_resource(&d
->res
);
286 * amba_device_add - add a previously allocated AMBA device structure
287 * @dev: AMBA device allocated by amba_device_alloc
288 * @parent: resource parent for this devices resources
290 * Claim the resource, and read the device cell ID if not already
291 * initialized. Register the AMBA device with the Linux device
294 int amba_device_add(struct amba_device
*dev
, struct resource
*parent
)
300 WARN_ON(dev
->irq
[0] == (unsigned int)-1);
301 WARN_ON(dev
->irq
[1] == (unsigned int)-1);
303 ret
= request_resource(parent
, &dev
->res
);
307 /* Hard-coded primecell ID instead of plug-n-play */
308 if (dev
->periphid
!= 0)
312 * Dynamically calculate the size of the resource
313 * and use this for iomap
315 size
= resource_size(&dev
->res
);
316 tmp
= ioremap(dev
->res
.start
, size
);
322 ret
= amba_get_enable_pclk(dev
);
327 * Read pid and cid based on size of resource
328 * they are located at end of region
330 for (pid
= 0, i
= 0; i
< 4; i
++)
331 pid
|= (readl(tmp
+ size
- 0x20 + 4 * i
) & 255) <<
333 for (cid
= 0, i
= 0; i
< 4; i
++)
334 cid
|= (readl(tmp
+ size
- 0x10 + 4 * i
) & 255) <<
337 amba_put_disable_pclk(dev
);
352 ret
= device_add(&dev
->dev
);
357 ret
= device_create_file(&dev
->dev
, &dev_attr_irq0
);
358 if (ret
== 0 && dev
->irq
[1])
359 ret
= device_create_file(&dev
->dev
, &dev_attr_irq1
);
363 device_unregister(&dev
->dev
);
366 release_resource(&dev
->res
);
370 EXPORT_SYMBOL_GPL(amba_device_add
);
372 static struct amba_device
*
373 amba_aphb_device_add(struct device
*parent
, const char *name
,
374 resource_size_t base
, size_t size
, int irq1
, int irq2
,
375 void *pdata
, unsigned int periphid
, u64 dma_mask
,
376 struct resource
*resbase
)
378 struct amba_device
*dev
;
381 dev
= amba_device_alloc(name
, base
, size
);
383 return ERR_PTR(-ENOMEM
);
385 dev
->dev
.coherent_dma_mask
= dma_mask
;
388 dev
->periphid
= periphid
;
389 dev
->dev
.platform_data
= pdata
;
390 dev
->dev
.parent
= parent
;
392 ret
= amba_device_add(dev
, resbase
);
394 amba_device_put(dev
);
402 amba_apb_device_add(struct device
*parent
, const char *name
,
403 resource_size_t base
, size_t size
, int irq1
, int irq2
,
404 void *pdata
, unsigned int periphid
)
406 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
407 periphid
, 0, &iomem_resource
);
409 EXPORT_SYMBOL_GPL(amba_apb_device_add
);
412 amba_ahb_device_add(struct device
*parent
, const char *name
,
413 resource_size_t base
, size_t size
, int irq1
, int irq2
,
414 void *pdata
, unsigned int periphid
)
416 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
417 periphid
, ~0ULL, &iomem_resource
);
419 EXPORT_SYMBOL_GPL(amba_ahb_device_add
);
422 amba_apb_device_add_res(struct device
*parent
, const char *name
,
423 resource_size_t base
, size_t size
, int irq1
,
424 int irq2
, void *pdata
, unsigned int periphid
,
425 struct resource
*resbase
)
427 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
428 periphid
, 0, resbase
);
430 EXPORT_SYMBOL_GPL(amba_apb_device_add_res
);
433 amba_ahb_device_add_res(struct device
*parent
, const char *name
,
434 resource_size_t base
, size_t size
, int irq1
,
435 int irq2
, void *pdata
, unsigned int periphid
,
436 struct resource
*resbase
)
438 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
439 periphid
, ~0ULL, resbase
);
441 EXPORT_SYMBOL_GPL(amba_ahb_device_add_res
);
444 static void amba_device_initialize(struct amba_device
*dev
, const char *name
)
446 device_initialize(&dev
->dev
);
448 dev_set_name(&dev
->dev
, "%s", name
);
449 dev
->dev
.release
= amba_device_release
;
450 dev
->dev
.bus
= &amba_bustype
;
451 dev
->dev
.dma_mask
= &dev
->dev
.coherent_dma_mask
;
452 dev
->res
.name
= dev_name(&dev
->dev
);
456 * amba_device_alloc - allocate an AMBA device
457 * @name: sysfs name of the AMBA device
458 * @base: base of AMBA device
459 * @size: size of AMBA device
461 * Allocate and initialize an AMBA device structure. Returns %NULL
464 struct amba_device
*amba_device_alloc(const char *name
, resource_size_t base
,
467 struct amba_device
*dev
;
469 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
471 amba_device_initialize(dev
, name
);
472 dev
->res
.start
= base
;
473 dev
->res
.end
= base
+ size
- 1;
474 dev
->res
.flags
= IORESOURCE_MEM
;
479 EXPORT_SYMBOL_GPL(amba_device_alloc
);
482 * amba_device_register - register an AMBA device
483 * @dev: AMBA device to register
484 * @parent: parent memory resource
486 * Setup the AMBA device, reading the cell ID if present.
487 * Claim the resource, and register the AMBA device with
488 * the Linux device manager.
490 int amba_device_register(struct amba_device
*dev
, struct resource
*parent
)
492 amba_device_initialize(dev
, dev
->dev
.init_name
);
493 dev
->dev
.init_name
= NULL
;
495 return amba_device_add(dev
, parent
);
499 * amba_device_put - put an AMBA device
500 * @dev: AMBA device to put
502 void amba_device_put(struct amba_device
*dev
)
504 put_device(&dev
->dev
);
506 EXPORT_SYMBOL_GPL(amba_device_put
);
509 * amba_device_unregister - unregister an AMBA device
510 * @dev: AMBA device to remove
512 * Remove the specified AMBA device from the Linux device
513 * manager. All files associated with this object will be
514 * destroyed, and device drivers notified that the device has
515 * been removed. The AMBA device's resources including
516 * the amba_device structure will be freed once all
517 * references to it have been dropped.
519 void amba_device_unregister(struct amba_device
*dev
)
521 device_unregister(&dev
->dev
);
526 struct amba_device
*dev
;
527 struct device
*parent
;
533 static int amba_find_match(struct device
*dev
, void *data
)
535 struct find_data
*d
= data
;
536 struct amba_device
*pcdev
= to_amba_device(dev
);
539 r
= (pcdev
->periphid
& d
->mask
) == d
->id
;
541 r
&= d
->parent
== dev
->parent
;
543 r
&= strcmp(dev_name(dev
), d
->busid
) == 0;
554 * amba_find_device - locate an AMBA device given a bus id
555 * @busid: bus id for device (or NULL)
556 * @parent: parent device (or NULL)
557 * @id: peripheral ID (or 0)
558 * @mask: peripheral ID mask (or 0)
560 * Return the AMBA device corresponding to the supplied parameters.
561 * If no device matches, returns NULL.
563 * NOTE: When a valid device is found, its refcount is
564 * incremented, and must be decremented before the returned
568 amba_find_device(const char *busid
, struct device
*parent
, unsigned int id
,
571 struct find_data data
;
574 data
.parent
= parent
;
579 bus_for_each_dev(&amba_bustype
, NULL
, &data
, amba_find_match
);
585 * amba_request_regions - request all mem regions associated with device
586 * @dev: amba_device structure for device
587 * @name: name, or NULL to use driver name
589 int amba_request_regions(struct amba_device
*dev
, const char *name
)
595 name
= dev
->dev
.driver
->name
;
597 size
= resource_size(&dev
->res
);
599 if (!request_mem_region(dev
->res
.start
, size
, name
))
606 * amba_release_regions - release mem regions associated with device
607 * @dev: amba_device structure for device
609 * Release regions claimed by a successful call to amba_request_regions.
611 void amba_release_regions(struct amba_device
*dev
)
615 size
= resource_size(&dev
->res
);
616 release_mem_region(dev
->res
.start
, size
);
619 EXPORT_SYMBOL(amba_driver_register
);
620 EXPORT_SYMBOL(amba_driver_unregister
);
621 EXPORT_SYMBOL(amba_device_register
);
622 EXPORT_SYMBOL(amba_device_unregister
);
623 EXPORT_SYMBOL(amba_find_device
);
624 EXPORT_SYMBOL(amba_request_regions
);
625 EXPORT_SYMBOL(amba_release_regions
);