edac: Rename the parent dev to pdev
[linux-2.6/libata-dev.git] / drivers / amba / bus.c
blobcc273226dbd014868ac68342d07225e0b095d6e1
1 /*
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.
9 */
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>
15 #include <linux/io.h>
16 #include <linux/pm.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/amba/bus.h>
20 #include <asm/irq.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)
28 int ret = 0;
30 while (table->mask) {
31 ret = (dev->periphid & table->mask) == table->id;
32 if (ret)
33 break;
34 table++;
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;
48 #ifdef CONFIG_HOTPLUG
49 static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
51 struct amba_device *pcdev = to_amba_device(dev);
52 int retval = 0;
54 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
55 if (retval)
56 return retval;
58 retval = add_uevent_var(env, "MODALIAS=amba:d%08X", pcdev->periphid);
59 return retval;
61 #else
62 #define amba_uevent NULL
63 #endif
65 #define amba_attr_func(name,fmt,arg...) \
66 static ssize_t name##_show(struct device *_dev, \
67 struct device_attribute *attr, char *buf) \
68 { \
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,
82 dev->res.flags);
84 static struct device_attribute amba_dev_attrs[] = {
85 __ATTR_RO(id),
86 __ATTR_RO(resource),
87 __ATTR_NULL,
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);
96 int ret = 0;
98 if (dev->driver && adrv->suspend)
99 ret = adrv->suspend(adev, mesg);
101 return ret;
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);
108 int ret = 0;
110 if (dev->driver && adrv->resume)
111 ret = adrv->resume(adev);
113 return ret;
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;
123 int ret = 0;
125 if (!drv)
126 return 0;
128 if (drv->pm) {
129 if (drv->pm->suspend)
130 ret = drv->pm->suspend(dev);
131 } else {
132 ret = amba_legacy_suspend(dev, PMSG_SUSPEND);
135 return ret;
138 static int amba_pm_resume(struct device *dev)
140 struct device_driver *drv = dev->driver;
141 int ret = 0;
143 if (!drv)
144 return 0;
146 if (drv->pm) {
147 if (drv->pm->resume)
148 ret = drv->pm->resume(dev);
149 } else {
150 ret = amba_legacy_resume(dev);
153 return ret;
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;
168 int ret = 0;
170 if (!drv)
171 return 0;
173 if (drv->pm) {
174 if (drv->pm->freeze)
175 ret = drv->pm->freeze(dev);
176 } else {
177 ret = amba_legacy_suspend(dev, PMSG_FREEZE);
180 return ret;
183 static int amba_pm_thaw(struct device *dev)
185 struct device_driver *drv = dev->driver;
186 int ret = 0;
188 if (!drv)
189 return 0;
191 if (drv->pm) {
192 if (drv->pm->thaw)
193 ret = drv->pm->thaw(dev);
194 } else {
195 ret = amba_legacy_resume(dev);
198 return ret;
201 static int amba_pm_poweroff(struct device *dev)
203 struct device_driver *drv = dev->driver;
204 int ret = 0;
206 if (!drv)
207 return 0;
209 if (drv->pm) {
210 if (drv->pm->poweroff)
211 ret = drv->pm->poweroff(dev);
212 } else {
213 ret = amba_legacy_suspend(dev, PMSG_HIBERNATE);
216 return ret;
219 static int amba_pm_restore(struct device *dev)
221 struct device_driver *drv = dev->driver;
222 int ret = 0;
224 if (!drv)
225 return 0;
227 if (drv->pm) {
228 if (drv->pm->restore)
229 ret = drv->pm->restore(dev);
230 } else {
231 ret = amba_legacy_resume(dev);
234 return ret;
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);
260 return ret;
263 static int amba_pm_runtime_resume(struct device *dev)
265 struct amba_device *pcdev = to_amba_device(dev);
266 int ret;
268 if (dev->driver) {
269 ret = clk_enable(pcdev->pclk);
270 /* Failure is probably fatal to the system, but... */
271 if (ret)
272 return ret;
275 return pm_generic_runtime_resume(dev);
277 #endif
279 #ifdef CONFIG_PM
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,
288 SET_RUNTIME_PM_OPS(
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 */
299 #define AMBA_PM NULL
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 = {
308 .name = "amba",
309 .dev_attrs = amba_dev_attrs,
310 .match = amba_match,
311 .uevent = amba_uevent,
312 .pm = AMBA_PM,
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");
325 int ret;
327 pcdev->pclk = pclk;
329 if (IS_ERR(pclk))
330 return PTR_ERR(pclk);
332 ret = clk_prepare(pclk);
333 if (ret) {
334 clk_put(pclk);
335 return ret;
338 ret = clk_enable(pclk);
339 if (ret) {
340 clk_unprepare(pclk);
341 clk_put(pclk);
344 return ret;
347 static void amba_put_disable_pclk(struct amba_device *pcdev)
349 struct clk *pclk = pcdev->pclk;
351 clk_disable(pclk);
352 clk_unprepare(pclk);
353 clk_put(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);
365 int ret;
367 do {
368 ret = amba_get_enable_pclk(pcdev);
369 if (ret)
370 break;
372 pm_runtime_get_noresume(dev);
373 pm_runtime_set_active(dev);
374 pm_runtime_enable(dev);
376 ret = pcdrv->probe(pcdev, id);
377 if (ret == 0)
378 break;
380 pm_runtime_disable(dev);
381 pm_runtime_set_suspended(dev);
382 pm_runtime_put_noidle(dev);
384 amba_put_disable_pclk(pcdev);
385 } while (0);
387 return ret;
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);
394 int ret;
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);
407 return ret;
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
422 * be called.
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
429 SETFN(probe);
430 SETFN(remove);
431 SETFN(shutdown);
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);
454 if (d->res.parent)
455 release_resource(&d->res);
456 kfree(d);
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
466 * manager.
468 int amba_device_add(struct amba_device *dev, struct resource *parent)
470 u32 size;
471 void __iomem *tmp;
472 int i, ret;
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);
478 if (ret)
479 goto err_out;
481 /* Hard-coded primecell ID instead of plug-n-play */
482 if (dev->periphid != 0)
483 goto skip_probe;
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);
491 if (!tmp) {
492 ret = -ENOMEM;
493 goto err_release;
496 ret = amba_get_enable_pclk(dev);
497 if (ret == 0) {
498 u32 pid, cid;
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) <<
506 (i * 8);
507 for (cid = 0, i = 0; i < 4; i++)
508 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
509 (i * 8);
511 amba_put_disable_pclk(dev);
513 if (cid == AMBA_CID)
514 dev->periphid = pid;
516 if (!dev->periphid)
517 ret = -ENODEV;
520 iounmap(tmp);
522 if (ret)
523 goto err_release;
525 skip_probe:
526 ret = device_add(&dev->dev);
527 if (ret)
528 goto err_release;
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);
534 if (ret == 0)
535 return ret;
537 device_unregister(&dev->dev);
539 err_release:
540 release_resource(&dev->res);
541 err_out:
542 return ret;
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);
549 if (name)
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
564 * on failure.
566 struct amba_device *amba_device_alloc(const char *name, resource_size_t base,
567 size_t size)
569 struct amba_device *dev;
571 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
572 if (dev) {
573 amba_device_initialize(dev, name);
574 dev->res.start = base;
575 dev->res.end = base + size - 1;
576 dev->res.flags = IORESOURCE_MEM;
579 return dev;
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);
630 struct find_data {
631 struct amba_device *dev;
632 struct device *parent;
633 const char *busid;
634 unsigned int id;
635 unsigned int mask;
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);
642 int r;
644 r = (pcdev->periphid & d->mask) == d->id;
645 if (d->parent)
646 r &= d->parent == dev->parent;
647 if (d->busid)
648 r &= strcmp(dev_name(dev), d->busid) == 0;
650 if (r) {
651 get_device(dev);
652 d->dev = pcdev;
655 return r;
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
670 * reference.
672 struct amba_device *
673 amba_find_device(const char *busid, struct device *parent, unsigned int id,
674 unsigned int mask)
676 struct find_data data;
678 data.dev = NULL;
679 data.parent = parent;
680 data.busid = busid;
681 data.id = id;
682 data.mask = mask;
684 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
686 return data.dev;
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)
696 int ret = 0;
697 u32 size;
699 if (!name)
700 name = dev->dev.driver->name;
702 size = resource_size(&dev->res);
704 if (!request_mem_region(dev->res.start, size, name))
705 ret = -EBUSY;
707 return ret;
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)
718 u32 size;
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);