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>
16 #include <linux/amba/bus.h>
19 #include <asm/sizes.h>
21 #define to_amba_device(d) container_of(d, struct amba_device, dev)
22 #define to_amba_driver(d) container_of(d, struct amba_driver, drv)
24 static struct amba_id *
25 amba_lookup(struct amba_id *table, struct amba_device *dev)
30 ret = (dev->periphid & table->mask) == table->id;
36 return ret ? table : NULL;
39 static int amba_match(struct device *dev, struct device_driver *drv)
41 struct amba_device *pcdev = to_amba_device(dev);
42 struct amba_driver *pcdrv = to_amba_driver(drv);
44 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
48 static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
50 struct amba_device *pcdev = to_amba_device(dev);
53 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
57 #define amba_uevent NULL
60 static int amba_suspend(struct device *dev, pm_message_t state)
62 struct amba_driver *drv = to_amba_driver(dev->driver);
65 if (dev->driver && drv->suspend)
66 ret = drv->suspend(to_amba_device(dev), state);
70 static int amba_resume(struct device *dev)
72 struct amba_driver *drv = to_amba_driver(dev->driver);
75 if (dev->driver && drv->resume)
76 ret = drv->resume(to_amba_device(dev));
80 #define amba_attr_func(name,fmt,arg...) \
81 static ssize_t name##_show(struct device *_dev, \
82 struct device_attribute *attr, char *buf) \
84 struct amba_device *dev = to_amba_device(_dev); \
85 return sprintf(buf, fmt, arg); \
88 #define amba_attr(name,fmt,arg...) \
89 amba_attr_func(name,fmt,arg) \
90 static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
92 amba_attr_func(id, "%08x\n", dev->periphid);
93 amba_attr(irq0, "%u\n", dev->irq[0]);
94 amba_attr(irq1, "%u\n", dev->irq[1]);
95 amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
96 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
99 static struct device_attribute amba_dev_attrs[] = {
106 * Primecells are part of the Advanced Microcontroller Bus Architecture,
107 * so we call the bus "amba".
109 static struct bus_type amba_bustype = {
111 .dev_attrs = amba_dev_attrs,
113 .uevent = amba_uevent,
114 .suspend = amba_suspend,
115 .resume = amba_resume,
118 static int __init amba_init(void)
120 return bus_register(&amba_bustype);
123 postcore_initcall(amba_init);
125 static int amba_get_enable_pclk(struct amba_device *pcdev)
127 struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
133 return PTR_ERR(pclk);
135 ret = clk_enable(pclk);
142 static void amba_put_disable_pclk(struct amba_device *pcdev)
144 struct clk *pclk = pcdev->pclk;
150 static int amba_get_enable_vcore(struct amba_device *pcdev)
152 struct regulator *vcore = regulator_get(&pcdev->dev, "vcore");
155 pcdev->vcore = vcore;
158 /* It is OK not to supply a vcore regulator */
159 if (PTR_ERR(vcore) == -ENODEV)
161 return PTR_ERR(vcore);
164 ret = regulator_enable(vcore);
166 regulator_put(vcore);
167 pcdev->vcore = ERR_PTR(-ENODEV);
173 static void amba_put_disable_vcore(struct amba_device *pcdev)
175 struct regulator *vcore = pcdev->vcore;
177 if (!IS_ERR(vcore)) {
178 regulator_disable(vcore);
179 regulator_put(vcore);
184 * These are the device model conversion veneers; they convert the
185 * device model structures to our more specific structures.
187 static int amba_probe(struct device *dev)
189 struct amba_device *pcdev = to_amba_device(dev);
190 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
191 struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
195 ret = amba_get_enable_vcore(pcdev);
199 ret = amba_get_enable_pclk(pcdev);
203 ret = pcdrv->probe(pcdev, id);
207 amba_put_disable_pclk(pcdev);
208 amba_put_disable_vcore(pcdev);
214 static int amba_remove(struct device *dev)
216 struct amba_device *pcdev = to_amba_device(dev);
217 struct amba_driver *drv = to_amba_driver(dev->driver);
218 int ret = drv->remove(pcdev);
220 amba_put_disable_pclk(pcdev);
221 amba_put_disable_vcore(pcdev);
226 static void amba_shutdown(struct device *dev)
228 struct amba_driver *drv = to_amba_driver(dev->driver);
229 drv->shutdown(to_amba_device(dev));
233 * amba_driver_register - register an AMBA device driver
234 * @drv: amba device driver structure
236 * Register an AMBA device driver with the Linux device model
237 * core. If devices pre-exist, the drivers probe function will
240 int amba_driver_register(struct amba_driver *drv)
242 drv->drv.bus = &amba_bustype;
244 #define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
249 return driver_register(&drv->drv);
253 * amba_driver_unregister - remove an AMBA device driver
254 * @drv: AMBA device driver structure to remove
256 * Unregister an AMBA device driver from the Linux device
257 * model. The device model will call the drivers remove function
258 * for each device the device driver is currently handling.
260 void amba_driver_unregister(struct amba_driver *drv)
262 driver_unregister(&drv->drv);
266 static void amba_device_release(struct device *dev)
268 struct amba_device *d = to_amba_device(dev);
271 release_resource(&d->res);
276 * amba_device_register - register an AMBA device
277 * @dev: AMBA device to register
278 * @parent: parent memory resource
280 * Setup the AMBA device, reading the cell ID if present.
281 * Claim the resource, and register the AMBA device with
282 * the Linux device manager.
284 int amba_device_register(struct amba_device *dev, struct resource *parent)
290 device_initialize(&dev->dev);
293 * Copy from device_add
295 if (dev->dev.init_name) {
296 dev_set_name(&dev->dev, "%s", dev->dev.init_name);
297 dev->dev.init_name = NULL;
300 dev->dev.release = amba_device_release;
301 dev->dev.bus = &amba_bustype;
302 dev->dev.dma_mask = &dev->dma_mask;
303 dev->res.name = dev_name(&dev->dev);
305 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
306 dev_warn(&dev->dev, "coherent dma mask is unset\n");
308 ret = request_resource(parent, &dev->res);
313 * Dynamically calculate the size of the resource
314 * and use this for iomap
316 size = resource_size(&dev->res);
317 tmp = ioremap(dev->res.start, size);
323 ret = amba_get_enable_pclk(dev);
328 * Read pid and cid based on size of resource
329 * they are located at end of region
331 for (pid = 0, i = 0; i < 4; i++)
332 pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
334 for (cid = 0, i = 0; i < 4; i++)
335 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
338 amba_put_disable_pclk(dev);
352 ret = device_add(&dev->dev);
356 if (dev->irq[0] != NO_IRQ)
357 ret = device_create_file(&dev->dev, &dev_attr_irq0);
358 if (ret == 0 && dev->irq[1] != NO_IRQ)
359 ret = device_create_file(&dev->dev, &dev_attr_irq1);
363 device_unregister(&dev->dev);
366 release_resource(&dev->res);
372 * amba_device_unregister - unregister an AMBA device
373 * @dev: AMBA device to remove
375 * Remove the specified AMBA device from the Linux device
376 * manager. All files associated with this object will be
377 * destroyed, and device drivers notified that the device has
378 * been removed. The AMBA device's resources including
379 * the amba_device structure will be freed once all
380 * references to it have been dropped.
382 void amba_device_unregister(struct amba_device *dev)
384 device_unregister(&dev->dev);
389 struct amba_device *dev;
390 struct device *parent;
396 static int amba_find_match(struct device *dev, void *data)
398 struct find_data *d = data;
399 struct amba_device *pcdev = to_amba_device(dev);
402 r = (pcdev->periphid & d->mask) == d->id;
404 r &= d->parent == dev->parent;
406 r &= strcmp(dev_name(dev), d->busid) == 0;
417 * amba_find_device - locate an AMBA device given a bus id
418 * @busid: bus id for device (or NULL)
419 * @parent: parent device (or NULL)
420 * @id: peripheral ID (or 0)
421 * @mask: peripheral ID mask (or 0)
423 * Return the AMBA device corresponding to the supplied parameters.
424 * If no device matches, returns NULL.
426 * NOTE: When a valid device is found, its refcount is
427 * incremented, and must be decremented before the returned
431 amba_find_device(const char *busid, struct device *parent, unsigned int id,
434 struct find_data data;
437 data.parent = parent;
442 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
448 * amba_request_regions - request all mem regions associated with device
449 * @dev: amba_device structure for device
450 * @name: name, or NULL to use driver name
452 int amba_request_regions(struct amba_device *dev, const char *name)
458 name = dev->dev.driver->name;
460 size = resource_size(&dev->res);
462 if (!request_mem_region(dev->res.start, size, name))
469 * amba_release_regions - release mem regions assoicated with device
470 * @dev: amba_device structure for device
472 * Release regions claimed by a successful call to amba_request_regions.
474 void amba_release_regions(struct amba_device *dev)
478 size = resource_size(&dev->res);
479 release_mem_region(dev->res.start, size);
482 EXPORT_SYMBOL(amba_driver_register);
483 EXPORT_SYMBOL(amba_driver_unregister);
484 EXPORT_SYMBOL(amba_device_register);
485 EXPORT_SYMBOL(amba_device_unregister);
486 EXPORT_SYMBOL(amba_find_device);
487 EXPORT_SYMBOL(amba_request_regions);
488 EXPORT_SYMBOL(amba_release_regions);