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-rw-r--r--arch/arm/common/amba.c357
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diff --git a/arch/arm/common/amba.c b/arch/arm/common/amba.c
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1/*
2 * linux/arch/arm/common/amba.c
3 *
4 * Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
5 *
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
14#include <asm/io.h>
15#include <asm/irq.h>
16#include <asm/hardware/amba.h>
17#include <asm/sizes.h>
18
19#define to_amba_device(d) container_of(d, struct amba_device, dev)
20#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
21
22static struct amba_id *
23amba_lookup(struct amba_id *table, struct amba_device *dev)
24{
25 int ret = 0;
26
27 while (table->mask) {
28 ret = (dev->periphid & table->mask) == table->id;
29 if (ret)
30 break;
31 table++;
32 }
33
34 return ret ? table : NULL;
35}
36
37static int amba_match(struct device *dev, struct device_driver *drv)
38{
39 struct amba_device *pcdev = to_amba_device(dev);
40 struct amba_driver *pcdrv = to_amba_driver(drv);
41
42 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
43}
44
45#ifdef CONFIG_HOTPLUG
46static int amba_hotplug(struct device *dev, char **envp, int nr_env, char *buf, int bufsz)
47{
48 struct amba_device *pcdev = to_amba_device(dev);
49
50 if (nr_env < 2)
51 return -ENOMEM;
52
53 snprintf(buf, bufsz, "AMBA_ID=%08x", pcdev->periphid);
54 *envp++ = buf;
55 *envp++ = NULL;
56 return 0;
57}
58#else
59#define amba_hotplug NULL
60#endif
61
62static int amba_suspend(struct device *dev, pm_message_t state)
63{
64 struct amba_driver *drv = to_amba_driver(dev->driver);
65 int ret = 0;
66
67 if (dev->driver && drv->suspend)
68 ret = drv->suspend(to_amba_device(dev), state);
69 return ret;
70}
71
72static int amba_resume(struct device *dev)
73{
74 struct amba_driver *drv = to_amba_driver(dev->driver);
75 int ret = 0;
76
77 if (dev->driver && drv->resume)
78 ret = drv->resume(to_amba_device(dev));
79 return ret;
80}
81
82/*
83 * Primecells are part of the Advanced Microcontroller Bus Architecture,
84 * so we call the bus "amba".
85 */
86static struct bus_type amba_bustype = {
87 .name = "amba",
88 .match = amba_match,
89 .hotplug = amba_hotplug,
90 .suspend = amba_suspend,
91 .resume = amba_resume,
92};
93
94static int __init amba_init(void)
95{
96 return bus_register(&amba_bustype);
97}
98
99postcore_initcall(amba_init);
100
101/*
102 * These are the device model conversion veneers; they convert the
103 * device model structures to our more specific structures.
104 */
105static int amba_probe(struct device *dev)
106{
107 struct amba_device *pcdev = to_amba_device(dev);
108 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
109 struct amba_id *id;
110
111 id = amba_lookup(pcdrv->id_table, pcdev);
112
113 return pcdrv->probe(pcdev, id);
114}
115
116static int amba_remove(struct device *dev)
117{
118 struct amba_driver *drv = to_amba_driver(dev->driver);
119 return drv->remove(to_amba_device(dev));
120}
121
122static void amba_shutdown(struct device *dev)
123{
124 struct amba_driver *drv = to_amba_driver(dev->driver);
125 drv->shutdown(to_amba_device(dev));
126}
127
128/**
129 * amba_driver_register - register an AMBA device driver
130 * @drv: amba device driver structure
131 *
132 * Register an AMBA device driver with the Linux device model
133 * core. If devices pre-exist, the drivers probe function will
134 * be called.
135 */
136int amba_driver_register(struct amba_driver *drv)
137{
138 drv->drv.bus = &amba_bustype;
139
140#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
141 SETFN(probe);
142 SETFN(remove);
143 SETFN(shutdown);
144
145 return driver_register(&drv->drv);
146}
147
148/**
149 * amba_driver_unregister - remove an AMBA device driver
150 * @drv: AMBA device driver structure to remove
151 *
152 * Unregister an AMBA device driver from the Linux device
153 * model. The device model will call the drivers remove function
154 * for each device the device driver is currently handling.
155 */
156void amba_driver_unregister(struct amba_driver *drv)
157{
158 driver_unregister(&drv->drv);
159}
160
161
162static void amba_device_release(struct device *dev)
163{
164 struct amba_device *d = to_amba_device(dev);
165
166 if (d->res.parent)
167 release_resource(&d->res);
168 kfree(d);
169}
170
171#define amba_attr(name,fmt,arg...) \
172static ssize_t show_##name(struct device *_dev, char *buf) \
173{ \
174 struct amba_device *dev = to_amba_device(_dev); \
175 return sprintf(buf, fmt, arg); \
176} \
177static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
178
179amba_attr(id, "%08x\n", dev->periphid);
180amba_attr(irq0, "%u\n", dev->irq[0]);
181amba_attr(irq1, "%u\n", dev->irq[1]);
182amba_attr(resource, "\t%08lx\t%08lx\t%08lx\n",
183 dev->res.start, dev->res.end, dev->res.flags);
184
185/**
186 * amba_device_register - register an AMBA device
187 * @dev: AMBA device to register
188 * @parent: parent memory resource
189 *
190 * Setup the AMBA device, reading the cell ID if present.
191 * Claim the resource, and register the AMBA device with
192 * the Linux device manager.
193 */
194int amba_device_register(struct amba_device *dev, struct resource *parent)
195{
196 u32 pid, cid;
197 void __iomem *tmp;
198 int i, ret;
199
200 dev->dev.release = amba_device_release;
201 dev->dev.bus = &amba_bustype;
202 dev->dev.dma_mask = &dev->dma_mask;
203 dev->res.name = dev->dev.bus_id;
204
205 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
206 dev_warn(&dev->dev, "coherent dma mask is unset\n");
207
208 ret = request_resource(parent, &dev->res);
209 if (ret == 0) {
210 tmp = ioremap(dev->res.start, SZ_4K);
211 if (!tmp) {
212 ret = -ENOMEM;
213 goto out;
214 }
215
216 for (pid = 0, i = 0; i < 4; i++)
217 pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
218 for (cid = 0, i = 0; i < 4; i++)
219 cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
220
221 iounmap(tmp);
222
223 if (cid == 0xb105f00d)
224 dev->periphid = pid;
225
226 if (dev->periphid)
227 ret = device_register(&dev->dev);
228 else
229 ret = -ENODEV;
230
231 if (ret == 0) {
232 device_create_file(&dev->dev, &dev_attr_id);
233 if (dev->irq[0] != NO_IRQ)
234 device_create_file(&dev->dev, &dev_attr_irq0);
235 if (dev->irq[1] != NO_IRQ)
236 device_create_file(&dev->dev, &dev_attr_irq1);
237 device_create_file(&dev->dev, &dev_attr_resource);
238 } else {
239 out:
240 release_resource(&dev->res);
241 }
242 }
243 return ret;
244}
245
246/**
247 * amba_device_unregister - unregister an AMBA device
248 * @dev: AMBA device to remove
249 *
250 * Remove the specified AMBA device from the Linux device
251 * manager. All files associated with this object will be
252 * destroyed, and device drivers notified that the device has
253 * been removed. The AMBA device's resources including
254 * the amba_device structure will be freed once all
255 * references to it have been dropped.
256 */
257void amba_device_unregister(struct amba_device *dev)
258{
259 device_unregister(&dev->dev);
260}
261
262
263struct find_data {
264 struct amba_device *dev;
265 struct device *parent;
266 const char *busid;
267 unsigned int id;
268 unsigned int mask;
269};
270
271static int amba_find_match(struct device *dev, void *data)
272{
273 struct find_data *d = data;
274 struct amba_device *pcdev = to_amba_device(dev);
275 int r;
276
277 r = (pcdev->periphid & d->mask) == d->id;
278 if (d->parent)
279 r &= d->parent == dev->parent;
280 if (d->busid)
281 r &= strcmp(dev->bus_id, d->busid) == 0;
282
283 if (r) {
284 get_device(dev);
285 d->dev = pcdev;
286 }
287
288 return r;
289}
290
291/**
292 * amba_find_device - locate an AMBA device given a bus id
293 * @busid: bus id for device (or NULL)
294 * @parent: parent device (or NULL)
295 * @id: peripheral ID (or 0)
296 * @mask: peripheral ID mask (or 0)
297 *
298 * Return the AMBA device corresponding to the supplied parameters.
299 * If no device matches, returns NULL.
300 *
301 * NOTE: When a valid device is found, its refcount is
302 * incremented, and must be decremented before the returned
303 * reference.
304 */
305struct amba_device *
306amba_find_device(const char *busid, struct device *parent, unsigned int id,
307 unsigned int mask)
308{
309 struct find_data data;
310
311 data.dev = NULL;
312 data.parent = parent;
313 data.busid = busid;
314 data.id = id;
315 data.mask = mask;
316
317 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
318
319 return data.dev;
320}
321
322/**
323 * amba_request_regions - request all mem regions associated with device
324 * @dev: amba_device structure for device
325 * @name: name, or NULL to use driver name
326 */
327int amba_request_regions(struct amba_device *dev, const char *name)
328{
329 int ret = 0;
330
331 if (!name)
332 name = dev->dev.driver->name;
333
334 if (!request_mem_region(dev->res.start, SZ_4K, name))
335 ret = -EBUSY;
336
337 return ret;
338}
339
340/**
341 * amba_release_regions - release mem regions assoicated with device
342 * @dev: amba_device structure for device
343 *
344 * Release regions claimed by a successful call to amba_request_regions.
345 */
346void amba_release_regions(struct amba_device *dev)
347{
348 release_mem_region(dev->res.start, SZ_4K);
349}
350
351EXPORT_SYMBOL(amba_driver_register);
352EXPORT_SYMBOL(amba_driver_unregister);
353EXPORT_SYMBOL(amba_device_register);
354EXPORT_SYMBOL(amba_device_unregister);
355EXPORT_SYMBOL(amba_find_device);
356EXPORT_SYMBOL(amba_request_regions);
357EXPORT_SYMBOL(amba_release_regions);