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 if (pm_runtime_is_irq_safe(dev
))
100 clk_disable(pcdev
->pclk
);
102 clk_disable_unprepare(pcdev
->pclk
);
108 static int amba_pm_runtime_resume(struct device
*dev
)
110 struct amba_device
*pcdev
= to_amba_device(dev
);
114 if (pm_runtime_is_irq_safe(dev
))
115 ret
= clk_enable(pcdev
->pclk
);
117 ret
= clk_prepare_enable(pcdev
->pclk
);
118 /* Failure is probably fatal to the system, but... */
123 return pm_generic_runtime_resume(dev
);
125 #endif /* CONFIG_PM */
127 static const struct dev_pm_ops amba_pm
= {
128 .suspend
= pm_generic_suspend
,
129 .resume
= pm_generic_resume
,
130 .freeze
= pm_generic_freeze
,
131 .thaw
= pm_generic_thaw
,
132 .poweroff
= pm_generic_poweroff
,
133 .restore
= pm_generic_restore
,
135 amba_pm_runtime_suspend
,
136 amba_pm_runtime_resume
,
142 * Primecells are part of the Advanced Microcontroller Bus Architecture,
143 * so we call the bus "amba".
145 struct bus_type amba_bustype
= {
147 .dev_attrs
= amba_dev_attrs
,
149 .uevent
= amba_uevent
,
153 static int __init
amba_init(void)
155 return bus_register(&amba_bustype
);
158 postcore_initcall(amba_init
);
160 static int amba_get_enable_pclk(struct amba_device
*pcdev
)
164 pcdev
->pclk
= clk_get(&pcdev
->dev
, "apb_pclk");
165 if (IS_ERR(pcdev
->pclk
))
166 return PTR_ERR(pcdev
->pclk
);
168 ret
= clk_prepare_enable(pcdev
->pclk
);
170 clk_put(pcdev
->pclk
);
175 static void amba_put_disable_pclk(struct amba_device
*pcdev
)
177 clk_disable_unprepare(pcdev
->pclk
);
178 clk_put(pcdev
->pclk
);
182 * These are the device model conversion veneers; they convert the
183 * device model structures to our more specific structures.
185 static int amba_probe(struct device
*dev
)
187 struct amba_device
*pcdev
= to_amba_device(dev
);
188 struct amba_driver
*pcdrv
= to_amba_driver(dev
->driver
);
189 const struct amba_id
*id
= amba_lookup(pcdrv
->id_table
, pcdev
);
193 ret
= dev_pm_domain_attach(dev
, true);
194 if (ret
== -EPROBE_DEFER
)
197 ret
= amba_get_enable_pclk(pcdev
);
199 dev_pm_domain_detach(dev
, true);
203 pm_runtime_get_noresume(dev
);
204 pm_runtime_set_active(dev
);
205 pm_runtime_enable(dev
);
207 ret
= pcdrv
->probe(pcdev
, id
);
211 pm_runtime_disable(dev
);
212 pm_runtime_set_suspended(dev
);
213 pm_runtime_put_noidle(dev
);
215 amba_put_disable_pclk(pcdev
);
216 dev_pm_domain_detach(dev
, true);
222 static int amba_remove(struct device
*dev
)
224 struct amba_device
*pcdev
= to_amba_device(dev
);
225 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
228 pm_runtime_get_sync(dev
);
229 ret
= drv
->remove(pcdev
);
230 pm_runtime_put_noidle(dev
);
232 /* Undo the runtime PM settings in amba_probe() */
233 pm_runtime_disable(dev
);
234 pm_runtime_set_suspended(dev
);
235 pm_runtime_put_noidle(dev
);
237 amba_put_disable_pclk(pcdev
);
238 dev_pm_domain_detach(dev
, true);
243 static void amba_shutdown(struct device
*dev
)
245 struct amba_driver
*drv
= to_amba_driver(dev
->driver
);
246 drv
->shutdown(to_amba_device(dev
));
250 * amba_driver_register - register an AMBA device driver
251 * @drv: amba device driver structure
253 * Register an AMBA device driver with the Linux device model
254 * core. If devices pre-exist, the drivers probe function will
257 int amba_driver_register(struct amba_driver
*drv
)
259 drv
->drv
.bus
= &amba_bustype
;
261 #define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
266 return driver_register(&drv
->drv
);
270 * amba_driver_unregister - remove an AMBA device driver
271 * @drv: AMBA device driver structure to remove
273 * Unregister an AMBA device driver from the Linux device
274 * model. The device model will call the drivers remove function
275 * for each device the device driver is currently handling.
277 void amba_driver_unregister(struct amba_driver
*drv
)
279 driver_unregister(&drv
->drv
);
283 static void amba_device_release(struct device
*dev
)
285 struct amba_device
*d
= to_amba_device(dev
);
288 release_resource(&d
->res
);
293 * amba_device_add - add a previously allocated AMBA device structure
294 * @dev: AMBA device allocated by amba_device_alloc
295 * @parent: resource parent for this devices resources
297 * Claim the resource, and read the device cell ID if not already
298 * initialized. Register the AMBA device with the Linux device
301 int amba_device_add(struct amba_device
*dev
, struct resource
*parent
)
307 WARN_ON(dev
->irq
[0] == (unsigned int)-1);
308 WARN_ON(dev
->irq
[1] == (unsigned int)-1);
310 ret
= request_resource(parent
, &dev
->res
);
314 /* Hard-coded primecell ID instead of plug-n-play */
315 if (dev
->periphid
!= 0)
319 * Dynamically calculate the size of the resource
320 * and use this for iomap
322 size
= resource_size(&dev
->res
);
323 tmp
= ioremap(dev
->res
.start
, size
);
329 ret
= amba_get_enable_pclk(dev
);
334 * Read pid and cid based on size of resource
335 * they are located at end of region
337 for (pid
= 0, i
= 0; i
< 4; i
++)
338 pid
|= (readl(tmp
+ size
- 0x20 + 4 * i
) & 255) <<
340 for (cid
= 0, i
= 0; i
< 4; i
++)
341 cid
|= (readl(tmp
+ size
- 0x10 + 4 * i
) & 255) <<
344 amba_put_disable_pclk(dev
);
346 if (cid
== AMBA_CID
|| cid
== CORESIGHT_CID
)
359 ret
= device_add(&dev
->dev
);
364 ret
= device_create_file(&dev
->dev
, &dev_attr_irq0
);
365 if (ret
== 0 && dev
->irq
[1])
366 ret
= device_create_file(&dev
->dev
, &dev_attr_irq1
);
370 device_unregister(&dev
->dev
);
373 release_resource(&dev
->res
);
377 EXPORT_SYMBOL_GPL(amba_device_add
);
379 static struct amba_device
*
380 amba_aphb_device_add(struct device
*parent
, const char *name
,
381 resource_size_t base
, size_t size
, int irq1
, int irq2
,
382 void *pdata
, unsigned int periphid
, u64 dma_mask
,
383 struct resource
*resbase
)
385 struct amba_device
*dev
;
388 dev
= amba_device_alloc(name
, base
, size
);
390 return ERR_PTR(-ENOMEM
);
392 dev
->dev
.coherent_dma_mask
= dma_mask
;
395 dev
->periphid
= periphid
;
396 dev
->dev
.platform_data
= pdata
;
397 dev
->dev
.parent
= parent
;
399 ret
= amba_device_add(dev
, resbase
);
401 amba_device_put(dev
);
409 amba_apb_device_add(struct device
*parent
, const char *name
,
410 resource_size_t base
, size_t size
, int irq1
, int irq2
,
411 void *pdata
, unsigned int periphid
)
413 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
414 periphid
, 0, &iomem_resource
);
416 EXPORT_SYMBOL_GPL(amba_apb_device_add
);
419 amba_ahb_device_add(struct device
*parent
, const char *name
,
420 resource_size_t base
, size_t size
, int irq1
, int irq2
,
421 void *pdata
, unsigned int periphid
)
423 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
424 periphid
, ~0ULL, &iomem_resource
);
426 EXPORT_SYMBOL_GPL(amba_ahb_device_add
);
429 amba_apb_device_add_res(struct device
*parent
, const char *name
,
430 resource_size_t base
, size_t size
, int irq1
,
431 int irq2
, void *pdata
, unsigned int periphid
,
432 struct resource
*resbase
)
434 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
435 periphid
, 0, resbase
);
437 EXPORT_SYMBOL_GPL(amba_apb_device_add_res
);
440 amba_ahb_device_add_res(struct device
*parent
, const char *name
,
441 resource_size_t base
, size_t size
, int irq1
,
442 int irq2
, void *pdata
, unsigned int periphid
,
443 struct resource
*resbase
)
445 return amba_aphb_device_add(parent
, name
, base
, size
, irq1
, irq2
, pdata
,
446 periphid
, ~0ULL, resbase
);
448 EXPORT_SYMBOL_GPL(amba_ahb_device_add_res
);
451 static void amba_device_initialize(struct amba_device
*dev
, const char *name
)
453 device_initialize(&dev
->dev
);
455 dev_set_name(&dev
->dev
, "%s", name
);
456 dev
->dev
.release
= amba_device_release
;
457 dev
->dev
.bus
= &amba_bustype
;
458 dev
->dev
.dma_mask
= &dev
->dev
.coherent_dma_mask
;
459 dev
->res
.name
= dev_name(&dev
->dev
);
463 * amba_device_alloc - allocate an AMBA device
464 * @name: sysfs name of the AMBA device
465 * @base: base of AMBA device
466 * @size: size of AMBA device
468 * Allocate and initialize an AMBA device structure. Returns %NULL
471 struct amba_device
*amba_device_alloc(const char *name
, resource_size_t base
,
474 struct amba_device
*dev
;
476 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
478 amba_device_initialize(dev
, name
);
479 dev
->res
.start
= base
;
480 dev
->res
.end
= base
+ size
- 1;
481 dev
->res
.flags
= IORESOURCE_MEM
;
486 EXPORT_SYMBOL_GPL(amba_device_alloc
);
489 * amba_device_register - register an AMBA device
490 * @dev: AMBA device to register
491 * @parent: parent memory resource
493 * Setup the AMBA device, reading the cell ID if present.
494 * Claim the resource, and register the AMBA device with
495 * the Linux device manager.
497 int amba_device_register(struct amba_device
*dev
, struct resource
*parent
)
499 amba_device_initialize(dev
, dev
->dev
.init_name
);
500 dev
->dev
.init_name
= NULL
;
502 return amba_device_add(dev
, parent
);
506 * amba_device_put - put an AMBA device
507 * @dev: AMBA device to put
509 void amba_device_put(struct amba_device
*dev
)
511 put_device(&dev
->dev
);
513 EXPORT_SYMBOL_GPL(amba_device_put
);
516 * amba_device_unregister - unregister an AMBA device
517 * @dev: AMBA device to remove
519 * Remove the specified AMBA device from the Linux device
520 * manager. All files associated with this object will be
521 * destroyed, and device drivers notified that the device has
522 * been removed. The AMBA device's resources including
523 * the amba_device structure will be freed once all
524 * references to it have been dropped.
526 void amba_device_unregister(struct amba_device
*dev
)
528 device_unregister(&dev
->dev
);
533 struct amba_device
*dev
;
534 struct device
*parent
;
540 static int amba_find_match(struct device
*dev
, void *data
)
542 struct find_data
*d
= data
;
543 struct amba_device
*pcdev
= to_amba_device(dev
);
546 r
= (pcdev
->periphid
& d
->mask
) == d
->id
;
548 r
&= d
->parent
== dev
->parent
;
550 r
&= strcmp(dev_name(dev
), d
->busid
) == 0;
561 * amba_find_device - locate an AMBA device given a bus id
562 * @busid: bus id for device (or NULL)
563 * @parent: parent device (or NULL)
564 * @id: peripheral ID (or 0)
565 * @mask: peripheral ID mask (or 0)
567 * Return the AMBA device corresponding to the supplied parameters.
568 * If no device matches, returns NULL.
570 * NOTE: When a valid device is found, its refcount is
571 * incremented, and must be decremented before the returned
575 amba_find_device(const char *busid
, struct device
*parent
, unsigned int id
,
578 struct find_data data
;
581 data
.parent
= parent
;
586 bus_for_each_dev(&amba_bustype
, NULL
, &data
, amba_find_match
);
592 * amba_request_regions - request all mem regions associated with device
593 * @dev: amba_device structure for device
594 * @name: name, or NULL to use driver name
596 int amba_request_regions(struct amba_device
*dev
, const char *name
)
602 name
= dev
->dev
.driver
->name
;
604 size
= resource_size(&dev
->res
);
606 if (!request_mem_region(dev
->res
.start
, size
, name
))
613 * amba_release_regions - release mem regions associated with device
614 * @dev: amba_device structure for device
616 * Release regions claimed by a successful call to amba_request_regions.
618 void amba_release_regions(struct amba_device
*dev
)
622 size
= resource_size(&dev
->res
);
623 release_mem_region(dev
->res
.start
, size
);
626 EXPORT_SYMBOL(amba_driver_register
);
627 EXPORT_SYMBOL(amba_driver_unregister
);
628 EXPORT_SYMBOL(amba_device_register
);
629 EXPORT_SYMBOL(amba_device_unregister
);
630 EXPORT_SYMBOL(amba_find_device
);
631 EXPORT_SYMBOL(amba_request_regions
);
632 EXPORT_SYMBOL(amba_release_regions
);