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/sizes.h>
19
20 #define to_amba_device(d) container_of(d, struct amba_device, dev)
21 #define to_amba_driver(d) container_of(d, struct amba_driver, drv)
22
23 static struct amba_id *
24 amba_lookup(struct amba_id *table, struct amba_device *dev)
25 {
26 int ret = 0;
27
28 while (table->mask) {
29 ret = (dev->periphid & table->mask) == table->id;
30 if (ret)
31 break;
32 table++;
33 }
34
35 return ret ? table : NULL;
36 }
37
38 static int amba_match(struct device *dev, struct device_driver *drv)
39 {
40 struct amba_device *pcdev = to_amba_device(dev);
41 struct amba_driver *pcdrv = to_amba_driver(drv);
42
43 return amba_lookup(pcdrv->id_table, pcdev) != NULL;
44 }
45
46 #ifdef CONFIG_HOTPLUG
47 static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
48 {
49 struct amba_device *pcdev = to_amba_device(dev);
50 int retval = 0;
51
52 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
53 return retval;
54 }
55 #else
56 #define amba_uevent NULL
57 #endif
58
59 static int amba_suspend(struct device *dev, pm_message_t state)
60 {
61 struct amba_driver *drv = to_amba_driver(dev->driver);
62 int ret = 0;
63
64 if (dev->driver && drv->suspend)
65 ret = drv->suspend(to_amba_device(dev), state);
66 return ret;
67 }
68
69 static int amba_resume(struct device *dev)
70 {
71 struct amba_driver *drv = to_amba_driver(dev->driver);
72 int ret = 0;
73
74 if (dev->driver && drv->resume)
75 ret = drv->resume(to_amba_device(dev));
76 return ret;
77 }
78
79 #define amba_attr_func(name,fmt,arg...) \
80 static ssize_t name##_show(struct device *_dev, \
81 struct device_attribute *attr, char *buf) \
82 { \
83 struct amba_device *dev = to_amba_device(_dev); \
84 return sprintf(buf, fmt, arg); \
85 }
86
87 #define amba_attr(name,fmt,arg...) \
88 amba_attr_func(name,fmt,arg) \
89 static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
90
91 amba_attr_func(id, "%08x\n", dev->periphid);
92 amba_attr(irq0, "%u\n", dev->irq[0]);
93 amba_attr(irq1, "%u\n", dev->irq[1]);
94 amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
95 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
96 dev->res.flags);
97
98 static struct device_attribute amba_dev_attrs[] = {
99 __ATTR_RO(id),
100 __ATTR_RO(resource),
101 __ATTR_NULL,
102 };
103
104 /*
105 * Primecells are part of the Advanced Microcontroller Bus Architecture,
106 * so we call the bus "amba".
107 */
108 static struct bus_type amba_bustype = {
109 .name = "amba",
110 .dev_attrs = amba_dev_attrs,
111 .match = amba_match,
112 .uevent = amba_uevent,
113 .suspend = amba_suspend,
114 .resume = amba_resume,
115 };
116
117 static int __init amba_init(void)
118 {
119 return bus_register(&amba_bustype);
120 }
121
122 postcore_initcall(amba_init);
123
124 /*
125 * These are the device model conversion veneers; they convert the
126 * device model structures to our more specific structures.
127 */
128 static int amba_probe(struct device *dev)
129 {
130 struct amba_device *pcdev = to_amba_device(dev);
131 struct amba_driver *pcdrv = to_amba_driver(dev->driver);
132 struct amba_id *id;
133
134 id = amba_lookup(pcdrv->id_table, pcdev);
135
136 return pcdrv->probe(pcdev, id);
137 }
138
139 static int amba_remove(struct device *dev)
140 {
141 struct amba_driver *drv = to_amba_driver(dev->driver);
142 return drv->remove(to_amba_device(dev));
143 }
144
145 static void amba_shutdown(struct device *dev)
146 {
147 struct amba_driver *drv = to_amba_driver(dev->driver);
148 drv->shutdown(to_amba_device(dev));
149 }
150
151 /**
152 * amba_driver_register - register an AMBA device driver
153 * @drv: amba device driver structure
154 *
155 * Register an AMBA device driver with the Linux device model
156 * core. If devices pre-exist, the drivers probe function will
157 * be called.
158 */
159 int amba_driver_register(struct amba_driver *drv)
160 {
161 drv->drv.bus = &amba_bustype;
162
163 #define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
164 SETFN(probe);
165 SETFN(remove);
166 SETFN(shutdown);
167
168 return driver_register(&drv->drv);
169 }
170
171 /**
172 * amba_driver_unregister - remove an AMBA device driver
173 * @drv: AMBA device driver structure to remove
174 *
175 * Unregister an AMBA device driver from the Linux device
176 * model. The device model will call the drivers remove function
177 * for each device the device driver is currently handling.
178 */
179 void amba_driver_unregister(struct amba_driver *drv)
180 {
181 driver_unregister(&drv->drv);
182 }
183
184
185 static void amba_device_release(struct device *dev)
186 {
187 struct amba_device *d = to_amba_device(dev);
188
189 if (d->res.parent)
190 release_resource(&d->res);
191 kfree(d);
192 }
193
194 /**
195 * amba_device_register - register an AMBA device
196 * @dev: AMBA device to register
197 * @parent: parent memory resource
198 *
199 * Setup the AMBA device, reading the cell ID if present.
200 * Claim the resource, and register the AMBA device with
201 * the Linux device manager.
202 */
203 int amba_device_register(struct amba_device *dev, struct resource *parent)
204 {
205 u32 pid, cid;
206 void __iomem *tmp;
207 int i, ret;
208
209 dev->dev.release = amba_device_release;
210 dev->dev.bus = &amba_bustype;
211 dev->dev.dma_mask = &dev->dma_mask;
212 dev->res.name = dev->dev.bus_id;
213
214 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
215 dev_warn(&dev->dev, "coherent dma mask is unset\n");
216
217 ret = request_resource(parent, &dev->res);
218 if (ret)
219 goto err_out;
220
221 tmp = ioremap(dev->res.start, SZ_4K);
222 if (!tmp) {
223 ret = -ENOMEM;
224 goto err_release;
225 }
226
227 for (pid = 0, i = 0; i < 4; i++)
228 pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
229 for (cid = 0, i = 0; i < 4; i++)
230 cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
231
232 iounmap(tmp);
233
234 if (cid == 0xb105f00d)
235 dev->periphid = pid;
236
237 if (!dev->periphid) {
238 ret = -ENODEV;
239 goto err_release;
240 }
241
242 ret = device_register(&dev->dev);
243 if (ret)
244 goto err_release;
245
246 if (dev->irq[0] != NO_IRQ)
247 ret = device_create_file(&dev->dev, &dev_attr_irq0);
248 if (ret == 0 && dev->irq[1] != NO_IRQ)
249 ret = device_create_file(&dev->dev, &dev_attr_irq1);
250 if (ret == 0)
251 return ret;
252
253 device_unregister(&dev->dev);
254
255 err_release:
256 release_resource(&dev->res);
257 err_out:
258 return ret;
259 }
260
261 /**
262 * amba_device_unregister - unregister an AMBA device
263 * @dev: AMBA device to remove
264 *
265 * Remove the specified AMBA device from the Linux device
266 * manager. All files associated with this object will be
267 * destroyed, and device drivers notified that the device has
268 * been removed. The AMBA device's resources including
269 * the amba_device structure will be freed once all
270 * references to it have been dropped.
271 */
272 void amba_device_unregister(struct amba_device *dev)
273 {
274 device_unregister(&dev->dev);
275 }
276
277
278 struct find_data {
279 struct amba_device *dev;
280 struct device *parent;
281 const char *busid;
282 unsigned int id;
283 unsigned int mask;
284 };
285
286 static int amba_find_match(struct device *dev, void *data)
287 {
288 struct find_data *d = data;
289 struct amba_device *pcdev = to_amba_device(dev);
290 int r;
291
292 r = (pcdev->periphid & d->mask) == d->id;
293 if (d->parent)
294 r &= d->parent == dev->parent;
295 if (d->busid)
296 r &= strcmp(dev->bus_id, d->busid) == 0;
297
298 if (r) {
299 get_device(dev);
300 d->dev = pcdev;
301 }
302
303 return r;
304 }
305
306 /**
307 * amba_find_device - locate an AMBA device given a bus id
308 * @busid: bus id for device (or NULL)
309 * @parent: parent device (or NULL)
310 * @id: peripheral ID (or 0)
311 * @mask: peripheral ID mask (or 0)
312 *
313 * Return the AMBA device corresponding to the supplied parameters.
314 * If no device matches, returns NULL.
315 *
316 * NOTE: When a valid device is found, its refcount is
317 * incremented, and must be decremented before the returned
318 * reference.
319 */
320 struct amba_device *
321 amba_find_device(const char *busid, struct device *parent, unsigned int id,
322 unsigned int mask)
323 {
324 struct find_data data;
325
326 data.dev = NULL;
327 data.parent = parent;
328 data.busid = busid;
329 data.id = id;
330 data.mask = mask;
331
332 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
333
334 return data.dev;
335 }
336
337 /**
338 * amba_request_regions - request all mem regions associated with device
339 * @dev: amba_device structure for device
340 * @name: name, or NULL to use driver name
341 */
342 int amba_request_regions(struct amba_device *dev, const char *name)
343 {
344 int ret = 0;
345
346 if (!name)
347 name = dev->dev.driver->name;
348
349 if (!request_mem_region(dev->res.start, SZ_4K, name))
350 ret = -EBUSY;
351
352 return ret;
353 }
354
355 /**
356 * amba_release_regions - release mem regions assoicated with device
357 * @dev: amba_device structure for device
358 *
359 * Release regions claimed by a successful call to amba_request_regions.
360 */
361 void amba_release_regions(struct amba_device *dev)
362 {
363 release_mem_region(dev->res.start, SZ_4K);
364 }
365
366 EXPORT_SYMBOL(amba_driver_register);
367 EXPORT_SYMBOL(amba_driver_unregister);
368 EXPORT_SYMBOL(amba_device_register);
369 EXPORT_SYMBOL(amba_device_unregister);
370 EXPORT_SYMBOL(amba_find_device);
371 EXPORT_SYMBOL(amba_request_regions);
372 EXPORT_SYMBOL(amba_release_regions);
373
|
This page was automatically generated by the
LXR engine.
|