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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2006-01-07 09:54:15 -0500
committerRussell King <rmk+kernel@arm.linux.org.uk>2006-01-07 09:54:15 -0500
commitde1d815fccee1f4766a7e56054ab0ec3f6f3a7db (patch)
treee767e18755de6efc55f8ea2759ece2aa74574b05 /drivers/amba
parent123656d4cc8c946f578ebd18c2050f5251720428 (diff)
[ARM] Move AMBA bus code to drivers/amba/
Make the AMBA bus code visible to other architectures. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/amba')
-rw-r--r--drivers/amba/Makefile2
-rw-r--r--drivers/amba/bus.c359
2 files changed, 361 insertions, 0 deletions
diff --git a/drivers/amba/Makefile b/drivers/amba/Makefile
new file mode 100644
index 000000000000..40fe74097be2
--- /dev/null
+++ b/drivers/amba/Makefile
@@ -0,0 +1,2 @@
1obj-y += bus.o
2
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
new file mode 100644
index 000000000000..1bbdd1693d57
--- /dev/null
+++ b/drivers/amba/bus.c
@@ -0,0 +1,359 @@
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#include <linux/string.h>
14#include <linux/slab.h>
15#include <linux/amba/bus.h>
16
17#include <asm/io.h>
18#include <asm/irq.h>
19#include <asm/sizes.h>
20
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)
23
24static struct amba_id *
25amba_lookup(struct amba_id *table, struct amba_device *dev)
26{
27 int ret = 0;
28
29 while (table->mask) {
30 ret = (dev->periphid & table->mask) == table->id;
31 if (ret)
32 break;
33 table++;
34 }
35
36 return ret ? table : NULL;
37}
38
39static int amba_match(struct device *dev, struct device_driver *drv)
40{
41 struct amba_device *pcdev = to_amba_device(dev);
42 struct amba_driver *pcdrv = to_amba_driver(drv);
43
44 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
45}
46
47#ifdef CONFIG_HOTPLUG
48static int amba_uevent(struct device *dev, char **envp, int nr_env, char *buf, int bufsz)
49{
50 struct amba_device *pcdev = to_amba_device(dev);
51
52 if (nr_env < 2)
53 return -ENOMEM;
54
55 snprintf(buf, bufsz, "AMBA_ID=%08x", pcdev->periphid);
56 *envp++ = buf;
57 *envp++ = NULL;
58 return 0;
59}
60#else
61#define amba_uevent NULL
62#endif
63
64static int amba_suspend(struct device *dev, pm_message_t state)
65{
66 struct amba_driver *drv = to_amba_driver(dev->driver);
67 int ret = 0;
68
69 if (dev->driver && drv->suspend)
70 ret = drv->suspend(to_amba_device(dev), state);
71 return ret;
72}
73
74static int amba_resume(struct device *dev)
75{
76 struct amba_driver *drv = to_amba_driver(dev->driver);
77 int ret = 0;
78
79 if (dev->driver && drv->resume)
80 ret = drv->resume(to_amba_device(dev));
81 return ret;
82}
83
84/*
85 * Primecells are part of the Advanced Microcontroller Bus Architecture,
86 * so we call the bus "amba".
87 */
88static struct bus_type amba_bustype = {
89 .name = "amba",
90 .match = amba_match,
91 .uevent = amba_uevent,
92 .suspend = amba_suspend,
93 .resume = amba_resume,
94};
95
96static int __init amba_init(void)
97{
98 return bus_register(&amba_bustype);
99}
100
101postcore_initcall(amba_init);
102
103/*
104 * These are the device model conversion veneers; they convert the
105 * device model structures to our more specific structures.
106 */
107static int amba_probe(struct device *dev)
108{
109 struct amba_device *pcdev = to_amba_device(dev);
110 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
111 struct amba_id *id;
112
113 id = amba_lookup(pcdrv->id_table, pcdev);
114
115 return pcdrv->probe(pcdev, id);
116}
117
118static int amba_remove(struct device *dev)
119{
120 struct amba_driver *drv = to_amba_driver(dev->driver);
121 return drv->remove(to_amba_device(dev));
122}
123
124static void amba_shutdown(struct device *dev)
125{
126 struct amba_driver *drv = to_amba_driver(dev->driver);
127 drv->shutdown(to_amba_device(dev));
128}
129
130/**
131 * amba_driver_register - register an AMBA device driver
132 * @drv: amba device driver structure
133 *
134 * Register an AMBA device driver with the Linux device model
135 * core. If devices pre-exist, the drivers probe function will
136 * be called.
137 */
138int amba_driver_register(struct amba_driver *drv)
139{
140 drv->drv.bus = &amba_bustype;
141
142#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
143 SETFN(probe);
144 SETFN(remove);
145 SETFN(shutdown);
146
147 return driver_register(&drv->drv);
148}
149
150/**
151 * amba_driver_unregister - remove an AMBA device driver
152 * @drv: AMBA device driver structure to remove
153 *
154 * Unregister an AMBA device driver from the Linux device
155 * model. The device model will call the drivers remove function
156 * for each device the device driver is currently handling.
157 */
158void amba_driver_unregister(struct amba_driver *drv)
159{
160 driver_unregister(&drv->drv);
161}
162
163
164static void amba_device_release(struct device *dev)
165{
166 struct amba_device *d = to_amba_device(dev);
167
168 if (d->res.parent)
169 release_resource(&d->res);
170 kfree(d);
171}
172
173#define amba_attr(name,fmt,arg...) \
174static ssize_t show_##name(struct device *_dev, struct device_attribute *attr, char *buf) \
175{ \
176 struct amba_device *dev = to_amba_device(_dev); \
177 return sprintf(buf, fmt, arg); \
178} \
179static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
180
181amba_attr(id, "%08x\n", dev->periphid);
182amba_attr(irq0, "%u\n", dev->irq[0]);
183amba_attr(irq1, "%u\n", dev->irq[1]);
184amba_attr(resource, "\t%08lx\t%08lx\t%08lx\n",
185 dev->res.start, dev->res.end, dev->res.flags);
186
187/**
188 * amba_device_register - register an AMBA device
189 * @dev: AMBA device to register
190 * @parent: parent memory resource
191 *
192 * Setup the AMBA device, reading the cell ID if present.
193 * Claim the resource, and register the AMBA device with
194 * the Linux device manager.
195 */
196int amba_device_register(struct amba_device *dev, struct resource *parent)
197{
198 u32 pid, cid;
199 void __iomem *tmp;
200 int i, ret;
201
202 dev->dev.release = amba_device_release;
203 dev->dev.bus = &amba_bustype;
204 dev->dev.dma_mask = &dev->dma_mask;
205 dev->res.name = dev->dev.bus_id;
206
207 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
208 dev_warn(&dev->dev, "coherent dma mask is unset\n");
209
210 ret = request_resource(parent, &dev->res);
211 if (ret == 0) {
212 tmp = ioremap(dev->res.start, SZ_4K);
213 if (!tmp) {
214 ret = -ENOMEM;
215 goto out;
216 }
217
218 for (pid = 0, i = 0; i < 4; i++)
219 pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
220 for (cid = 0, i = 0; i < 4; i++)
221 cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
222
223 iounmap(tmp);
224
225 if (cid == 0xb105f00d)
226 dev->periphid = pid;
227
228 if (dev->periphid)
229 ret = device_register(&dev->dev);
230 else
231 ret = -ENODEV;
232
233 if (ret == 0) {
234 device_create_file(&dev->dev, &dev_attr_id);
235 if (dev->irq[0] != NO_IRQ)
236 device_create_file(&dev->dev, &dev_attr_irq0);
237 if (dev->irq[1] != NO_IRQ)
238 device_create_file(&dev->dev, &dev_attr_irq1);
239 device_create_file(&dev->dev, &dev_attr_resource);
240 } else {
241 out:
242 release_resource(&dev->res);
243 }
244 }
245 return ret;
246}
247
248/**
249 * amba_device_unregister - unregister an AMBA device
250 * @dev: AMBA device to remove
251 *
252 * Remove the specified AMBA device from the Linux device
253 * manager. All files associated with this object will be
254 * destroyed, and device drivers notified that the device has
255 * been removed. The AMBA device's resources including
256 * the amba_device structure will be freed once all
257 * references to it have been dropped.
258 */
259void amba_device_unregister(struct amba_device *dev)
260{
261 device_unregister(&dev->dev);
262}
263
264
265struct find_data {
266 struct amba_device *dev;
267 struct device *parent;
268 const char *busid;
269 unsigned int id;
270 unsigned int mask;
271};
272
273static int amba_find_match(struct device *dev, void *data)
274{
275 struct find_data *d = data;
276 struct amba_device *pcdev = to_amba_device(dev);
277 int r;
278
279 r = (pcdev->periphid & d->mask) == d->id;
280 if (d->parent)
281 r &= d->parent == dev->parent;
282 if (d->busid)
283 r &= strcmp(dev->bus_id, d->busid) == 0;
284
285 if (r) {
286 get_device(dev);
287 d->dev = pcdev;
288 }
289
290 return r;
291}
292
293/**
294 * amba_find_device - locate an AMBA device given a bus id
295 * @busid: bus id for device (or NULL)
296 * @parent: parent device (or NULL)
297 * @id: peripheral ID (or 0)
298 * @mask: peripheral ID mask (or 0)
299 *
300 * Return the AMBA device corresponding to the supplied parameters.
301 * If no device matches, returns NULL.
302 *
303 * NOTE: When a valid device is found, its refcount is
304 * incremented, and must be decremented before the returned
305 * reference.
306 */
307struct amba_device *
308amba_find_device(const char *busid, struct device *parent, unsigned int id,
309 unsigned int mask)
310{
311 struct find_data data;
312
313 data.dev = NULL;
314 data.parent = parent;
315 data.busid = busid;
316 data.id = id;
317 data.mask = mask;
318
319 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
320
321 return data.dev;
322}
323
324/**
325 * amba_request_regions - request all mem regions associated with device
326 * @dev: amba_device structure for device
327 * @name: name, or NULL to use driver name
328 */
329int amba_request_regions(struct amba_device *dev, const char *name)
330{
331 int ret = 0;
332
333 if (!name)
334 name = dev->dev.driver->name;
335
336 if (!request_mem_region(dev->res.start, SZ_4K, name))
337 ret = -EBUSY;
338
339 return ret;
340}
341
342/**
343 * amba_release_regions - release mem regions assoicated with device
344 * @dev: amba_device structure for device
345 *
346 * Release regions claimed by a successful call to amba_request_regions.
347 */
348void amba_release_regions(struct amba_device *dev)
349{
350 release_mem_region(dev->res.start, SZ_4K);
351}
352
353EXPORT_SYMBOL(amba_driver_register);
354EXPORT_SYMBOL(amba_driver_unregister);
355EXPORT_SYMBOL(amba_device_register);
356EXPORT_SYMBOL(amba_device_unregister);
357EXPORT_SYMBOL(amba_find_device);
358EXPORT_SYMBOL(amba_request_regions);
359EXPORT_SYMBOL(amba_release_regions);