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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/io.h>
16#include <linux/amba/bus.h>
17
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, struct kobj_uevent_env *env)
49{
50 struct amba_device *pcdev = to_amba_device(dev);
51 int retval = 0;
52
53 retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid);
54 return retval;
55}
56#else
57#define amba_uevent NULL
58#endif
59
60static int amba_suspend(struct device *dev, pm_message_t state)
61{
62 struct amba_driver *drv = to_amba_driver(dev->driver);
63 int ret = 0;
64
65 if (dev->driver && drv->suspend)
66 ret = drv->suspend(to_amba_device(dev), state);
67 return ret;
68}
69
70static int amba_resume(struct device *dev)
71{
72 struct amba_driver *drv = to_amba_driver(dev->driver);
73 int ret = 0;
74
75 if (dev->driver && drv->resume)
76 ret = drv->resume(to_amba_device(dev));
77 return ret;
78}
79
80#define amba_attr_func(name,fmt,arg...) \
81static ssize_t name##_show(struct device *_dev, \
82 struct device_attribute *attr, char *buf) \
83{ \
84 struct amba_device *dev = to_amba_device(_dev); \
85 return sprintf(buf, fmt, arg); \
86}
87
88#define amba_attr(name,fmt,arg...) \
89amba_attr_func(name,fmt,arg) \
90static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL)
91
92amba_attr_func(id, "%08x\n", dev->periphid);
93amba_attr(irq0, "%u\n", dev->irq[0]);
94amba_attr(irq1, "%u\n", dev->irq[1]);
95amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n",
96 (unsigned long long)dev->res.start, (unsigned long long)dev->res.end,
97 dev->res.flags);
98
99static struct device_attribute amba_dev_attrs[] = {
100 __ATTR_RO(id),
101 __ATTR_RO(resource),
102 __ATTR_NULL,
103};
104
105
106
107
108
109static struct bus_type amba_bustype = {
110 .name = "amba",
111 .dev_attrs = amba_dev_attrs,
112 .match = amba_match,
113 .uevent = amba_uevent,
114 .suspend = amba_suspend,
115 .resume = amba_resume,
116};
117
118static int __init amba_init(void)
119{
120 return bus_register(&amba_bustype);
121}
122
123postcore_initcall(amba_init);
124
125static int amba_get_enable_pclk(struct amba_device *pcdev)
126{
127 struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
128 int ret;
129
130 pcdev->pclk = pclk;
131
132 if (IS_ERR(pclk))
133 return PTR_ERR(pclk);
134
135 ret = clk_enable(pclk);
136 if (ret)
137 clk_put(pclk);
138
139 return ret;
140}
141
142static void amba_put_disable_pclk(struct amba_device *pcdev)
143{
144 struct clk *pclk = pcdev->pclk;
145
146 clk_disable(pclk);
147 clk_put(pclk);
148}
149
150static int amba_get_enable_vcore(struct amba_device *pcdev)
151{
152 struct regulator *vcore = regulator_get(&pcdev->dev, "vcore");
153 int ret;
154
155 pcdev->vcore = vcore;
156
157 if (IS_ERR(vcore)) {
158
159 if (PTR_ERR(vcore) == -ENODEV)
160 return 0;
161 return PTR_ERR(vcore);
162 }
163
164 ret = regulator_enable(vcore);
165 if (ret) {
166 regulator_put(vcore);
167 pcdev->vcore = ERR_PTR(-ENODEV);
168 }
169
170 return ret;
171}
172
173static void amba_put_disable_vcore(struct amba_device *pcdev)
174{
175 struct regulator *vcore = pcdev->vcore;
176
177 if (!IS_ERR(vcore)) {
178 regulator_disable(vcore);
179 regulator_put(vcore);
180 }
181}
182
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185
186
187static int amba_probe(struct device *dev)
188{
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);
192 int ret;
193
194 do {
195 ret = amba_get_enable_vcore(pcdev);
196 if (ret)
197 break;
198
199 ret = amba_get_enable_pclk(pcdev);
200 if (ret)
201 break;
202
203 ret = pcdrv->probe(pcdev, id);
204 if (ret == 0)
205 break;
206
207 amba_put_disable_pclk(pcdev);
208 amba_put_disable_vcore(pcdev);
209 } while (0);
210
211 return ret;
212}
213
214static int amba_remove(struct device *dev)
215{
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);
219
220 amba_put_disable_pclk(pcdev);
221 amba_put_disable_vcore(pcdev);
222
223 return ret;
224}
225
226static void amba_shutdown(struct device *dev)
227{
228 struct amba_driver *drv = to_amba_driver(dev->driver);
229 drv->shutdown(to_amba_device(dev));
230}
231
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239
240int amba_driver_register(struct amba_driver *drv)
241{
242 drv->drv.bus = &amba_bustype;
243
244#define SETFN(fn) if (drv->fn) drv->drv.fn = amba_##fn
245 SETFN(probe);
246 SETFN(remove);
247 SETFN(shutdown);
248
249 return driver_register(&drv->drv);
250}
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259
260void amba_driver_unregister(struct amba_driver *drv)
261{
262 driver_unregister(&drv->drv);
263}
264
265
266static void amba_device_release(struct device *dev)
267{
268 struct amba_device *d = to_amba_device(dev);
269
270 if (d->res.parent)
271 release_resource(&d->res);
272 kfree(d);
273}
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283
284int amba_device_register(struct amba_device *dev, struct resource *parent)
285{
286 u32 size;
287 void __iomem *tmp;
288 int i, ret;
289
290 device_initialize(&dev->dev);
291
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293
294
295 if (dev->dev.init_name) {
296 dev_set_name(&dev->dev, "%s", dev->dev.init_name);
297 dev->dev.init_name = NULL;
298 }
299
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);
304
305 if (!dev->dev.coherent_dma_mask && dev->dma_mask)
306 dev_warn(&dev->dev, "coherent dma mask is unset\n");
307
308 ret = request_resource(parent, &dev->res);
309 if (ret)
310 goto err_out;
311
312
313
314
315
316 size = resource_size(&dev->res);
317 tmp = ioremap(dev->res.start, size);
318 if (!tmp) {
319 ret = -ENOMEM;
320 goto err_release;
321 }
322
323 ret = amba_get_enable_pclk(dev);
324 if (ret == 0) {
325 u32 pid, cid;
326
327
328
329
330
331 for (pid = 0, i = 0; i < 4; i++)
332 pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
333 (i * 8);
334 for (cid = 0, i = 0; i < 4; i++)
335 cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
336 (i * 8);
337
338 amba_put_disable_pclk(dev);
339
340 if (cid == AMBA_CID)
341 dev->periphid = pid;
342
343 if (!dev->periphid)
344 ret = -ENODEV;
345 }
346
347 iounmap(tmp);
348
349 if (ret)
350 goto err_release;
351
352 ret = device_add(&dev->dev);
353 if (ret)
354 goto err_release;
355
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);
360 if (ret == 0)
361 return ret;
362
363 device_unregister(&dev->dev);
364
365 err_release:
366 release_resource(&dev->res);
367 err_out:
368 return ret;
369}
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381
382void amba_device_unregister(struct amba_device *dev)
383{
384 device_unregister(&dev->dev);
385}
386
387
388struct find_data {
389 struct amba_device *dev;
390 struct device *parent;
391 const char *busid;
392 unsigned int id;
393 unsigned int mask;
394};
395
396static int amba_find_match(struct device *dev, void *data)
397{
398 struct find_data *d = data;
399 struct amba_device *pcdev = to_amba_device(dev);
400 int r;
401
402 r = (pcdev->periphid & d->mask) == d->id;
403 if (d->parent)
404 r &= d->parent == dev->parent;
405 if (d->busid)
406 r &= strcmp(dev_name(dev), d->busid) == 0;
407
408 if (r) {
409 get_device(dev);
410 d->dev = pcdev;
411 }
412
413 return r;
414}
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429
430struct amba_device *
431amba_find_device(const char *busid, struct device *parent, unsigned int id,
432 unsigned int mask)
433{
434 struct find_data data;
435
436 data.dev = NULL;
437 data.parent = parent;
438 data.busid = busid;
439 data.id = id;
440 data.mask = mask;
441
442 bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
443
444 return data.dev;
445}
446
447
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449
450
451
452int amba_request_regions(struct amba_device *dev, const char *name)
453{
454 int ret = 0;
455 u32 size;
456
457 if (!name)
458 name = dev->dev.driver->name;
459
460 size = resource_size(&dev->res);
461
462 if (!request_mem_region(dev->res.start, size, name))
463 ret = -EBUSY;
464
465 return ret;
466}
467
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473
474void amba_release_regions(struct amba_device *dev)
475{
476 u32 size;
477
478 size = resource_size(&dev->res);
479 release_mem_region(dev->res.start, size);
480}
481
482EXPORT_SYMBOL(amba_driver_register);
483EXPORT_SYMBOL(amba_driver_unregister);
484EXPORT_SYMBOL(amba_device_register);
485EXPORT_SYMBOL(amba_device_unregister);
486EXPORT_SYMBOL(amba_find_device);
487EXPORT_SYMBOL(amba_request_regions);
488EXPORT_SYMBOL(amba_release_regions);
489