ASoC: Intel: fix platform_no_drv_owner.cocci warnings
[linux-2.6/btrfs-unstable.git] / drivers / amba / bus.c
blob52ddd9fbb55e9c6e802b88ed337a420a59526ea9
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/pm_domain.h>
19 #include <linux/amba/bus.h>
20 #include <linux/sizes.h>
22 #include <asm/irq.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)
29 int ret = 0;
31 while (table->mask) {
32 ret = (dev->periphid & table->mask) == table->id;
33 if (ret)
34 break;
35 table++;
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);
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;
62 #define amba_attr_func(name,fmt,arg...) \
63 static ssize_t name##_show(struct device *_dev, \
64 struct device_attribute *attr, char *buf) \
65 { \
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,
79 dev->res.flags);
81 static struct device_attribute amba_dev_attrs[] = {
82 __ATTR_RO(id),
83 __ATTR_RO(resource),
84 __ATTR_NULL,
87 #ifdef CONFIG_PM
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);
101 else
102 clk_disable_unprepare(pcdev->pclk);
105 return ret;
108 static int amba_pm_runtime_resume(struct device *dev)
110 struct amba_device *pcdev = to_amba_device(dev);
111 int ret;
113 if (dev->driver) {
114 if (pm_runtime_is_irq_safe(dev))
115 ret = clk_enable(pcdev->pclk);
116 else
117 ret = clk_prepare_enable(pcdev->pclk);
118 /* Failure is probably fatal to the system, but... */
119 if (ret)
120 return ret;
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,
134 SET_RUNTIME_PM_OPS(
135 amba_pm_runtime_suspend,
136 amba_pm_runtime_resume,
137 NULL
142 * Primecells are part of the Advanced Microcontroller Bus Architecture,
143 * so we call the bus "amba".
145 struct bus_type amba_bustype = {
146 .name = "amba",
147 .dev_attrs = amba_dev_attrs,
148 .match = amba_match,
149 .uevent = amba_uevent,
150 .pm = &amba_pm,
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)
162 int ret;
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);
169 if (ret)
170 clk_put(pcdev->pclk);
172 return ret;
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);
190 int ret;
192 do {
193 ret = dev_pm_domain_attach(dev, true);
194 if (ret == -EPROBE_DEFER)
195 break;
197 ret = amba_get_enable_pclk(pcdev);
198 if (ret) {
199 dev_pm_domain_detach(dev, true);
200 break;
203 pm_runtime_get_noresume(dev);
204 pm_runtime_set_active(dev);
205 pm_runtime_enable(dev);
207 ret = pcdrv->probe(pcdev, id);
208 if (ret == 0)
209 break;
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);
217 } while (0);
219 return ret;
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);
226 int ret;
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);
240 return ret;
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
255 * be called.
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
262 SETFN(probe);
263 SETFN(remove);
264 SETFN(shutdown);
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);
287 if (d->res.parent)
288 release_resource(&d->res);
289 kfree(d);
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
299 * manager.
301 int amba_device_add(struct amba_device *dev, struct resource *parent)
303 u32 size;
304 void __iomem *tmp;
305 int i, ret;
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);
311 if (ret)
312 goto err_out;
314 /* Hard-coded primecell ID instead of plug-n-play */
315 if (dev->periphid != 0)
316 goto skip_probe;
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);
324 if (!tmp) {
325 ret = -ENOMEM;
326 goto err_release;
329 ret = amba_get_enable_pclk(dev);
330 if (ret == 0) {
331 u32 pid, cid;
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) <<
339 (i * 8);
340 for (cid = 0, i = 0; i < 4; i++)
341 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
342 (i * 8);
344 amba_put_disable_pclk(dev);
346 if (cid == AMBA_CID || cid == CORESIGHT_CID)
347 dev->periphid = pid;
349 if (!dev->periphid)
350 ret = -ENODEV;
353 iounmap(tmp);
355 if (ret)
356 goto err_release;
358 skip_probe:
359 ret = device_add(&dev->dev);
360 if (ret)
361 goto err_release;
363 if (dev->irq[0])
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);
367 if (ret == 0)
368 return ret;
370 device_unregister(&dev->dev);
372 err_release:
373 release_resource(&dev->res);
374 err_out:
375 return ret;
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;
386 int ret;
388 dev = amba_device_alloc(name, base, size);
389 if (!dev)
390 return ERR_PTR(-ENOMEM);
392 dev->dev.coherent_dma_mask = dma_mask;
393 dev->irq[0] = irq1;
394 dev->irq[1] = irq2;
395 dev->periphid = periphid;
396 dev->dev.platform_data = pdata;
397 dev->dev.parent = parent;
399 ret = amba_device_add(dev, resbase);
400 if (ret) {
401 amba_device_put(dev);
402 return ERR_PTR(ret);
405 return dev;
408 struct amba_device *
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);
418 struct amba_device *
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);
428 struct amba_device *
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);
439 struct amba_device *
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);
454 if (name)
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
469 * on failure.
471 struct amba_device *amba_device_alloc(const char *name, resource_size_t base,
472 size_t size)
474 struct amba_device *dev;
476 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
477 if (dev) {
478 amba_device_initialize(dev, name);
479 dev->res.start = base;
480 dev->res.end = base + size - 1;
481 dev->res.flags = IORESOURCE_MEM;
484 return dev;
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);
532 struct find_data {
533 struct amba_device *dev;
534 struct device *parent;
535 const char *busid;
536 unsigned int id;
537 unsigned int mask;
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);
544 int r;
546 r = (pcdev->periphid & d->mask) == d->id;
547 if (d->parent)
548 r &= d->parent == dev->parent;
549 if (d->busid)
550 r &= strcmp(dev_name(dev), d->busid) == 0;
552 if (r) {
553 get_device(dev);
554 d->dev = pcdev;
557 return r;
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
572 * reference.
574 struct amba_device *
575 amba_find_device(const char *busid, struct device *parent, unsigned int id,
576 unsigned int mask)
578 struct find_data data;
580 data.dev = NULL;
581 data.parent = parent;
582 data.busid = busid;
583 data.id = id;
584 data.mask = mask;
586 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
588 return data.dev;
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)
598 int ret = 0;
599 u32 size;
601 if (!name)
602 name = dev->dev.driver->name;
604 size = resource_size(&dev->res);
606 if (!request_mem_region(dev->res.start, size, name))
607 ret = -EBUSY;
609 return ret;
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)
620 u32 size;
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);