diff options
Diffstat (limited to 'drivers/amba/bus.c')
-rw-r--r-- | drivers/amba/bus.c | 359 |
1 files changed, 359 insertions, 0 deletions
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 | |||
24 | static struct amba_id * | ||
25 | amba_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 | |||
39 | static 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 | ||
48 | static 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 | |||
64 | static 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 | |||
74 | static 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 | */ | ||
88 | static 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 | |||
96 | static int __init amba_init(void) | ||
97 | { | ||
98 | return bus_register(&amba_bustype); | ||
99 | } | ||
100 | |||
101 | postcore_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 | */ | ||
107 | static 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 | |||
118 | static 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 | |||
124 | static 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 | */ | ||
138 | int 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 | */ | ||
158 | void amba_driver_unregister(struct amba_driver *drv) | ||
159 | { | ||
160 | driver_unregister(&drv->drv); | ||
161 | } | ||
162 | |||
163 | |||
164 | static 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...) \ | ||
174 | static 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 | } \ | ||
179 | static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL) | ||
180 | |||
181 | amba_attr(id, "%08x\n", dev->periphid); | ||
182 | amba_attr(irq0, "%u\n", dev->irq[0]); | ||
183 | amba_attr(irq1, "%u\n", dev->irq[1]); | ||
184 | amba_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 | */ | ||
196 | int 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 | */ | ||
259 | void amba_device_unregister(struct amba_device *dev) | ||
260 | { | ||
261 | device_unregister(&dev->dev); | ||
262 | } | ||
263 | |||
264 | |||
265 | struct 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 | |||
273 | static 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 | */ | ||
307 | struct amba_device * | ||
308 | amba_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 | */ | ||
329 | int 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 | */ | ||
348 | void amba_release_regions(struct amba_device *dev) | ||
349 | { | ||
350 | release_mem_region(dev->res.start, SZ_4K); | ||
351 | } | ||
352 | |||
353 | EXPORT_SYMBOL(amba_driver_register); | ||
354 | EXPORT_SYMBOL(amba_driver_unregister); | ||
355 | EXPORT_SYMBOL(amba_device_register); | ||
356 | EXPORT_SYMBOL(amba_device_unregister); | ||
357 | EXPORT_SYMBOL(amba_find_device); | ||
358 | EXPORT_SYMBOL(amba_request_regions); | ||
359 | EXPORT_SYMBOL(amba_release_regions); | ||