summaryrefslogtreecommitdiffstats
path: root/sound/ac97/bus.c
blob: 31f858eceffcb29937a05b143e920f6b8b8abfef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
/*
 * Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/idr.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <sound/ac97/codec.h>
#include <sound/ac97/controller.h>
#include <sound/ac97/regs.h>

#include "ac97_core.h"

/*
 * Protects ac97_controllers and each ac97_controller structure.
 */
static DEFINE_MUTEX(ac97_controllers_mutex);
static DEFINE_IDR(ac97_adapter_idr);
static LIST_HEAD(ac97_controllers);

static struct bus_type ac97_bus_type;

static inline struct ac97_controller*
to_ac97_controller(struct device *ac97_adapter)
{
	return container_of(ac97_adapter, struct ac97_controller, adap);
}

static int ac97_unbound_ctrl_write(struct ac97_controller *adrv, int slot,
		     unsigned short reg, unsigned short val)
{
	return -ENODEV;
}

static int ac97_unbound_ctrl_read(struct ac97_controller *adrv, int slot,
				  unsigned short reg)
{
	return -ENODEV;
}

static const struct ac97_controller_ops ac97_unbound_ctrl_ops = {
	.write = ac97_unbound_ctrl_write,
	.read = ac97_unbound_ctrl_read,
};

static struct ac97_controller ac97_unbound_ctrl = {
	.ops = &ac97_unbound_ctrl_ops,
};

static struct ac97_codec_device *
ac97_codec_find(struct ac97_controller *ac97_ctrl, unsigned int codec_num)
{
	if (codec_num >= AC97_BUS_MAX_CODECS)
		return ERR_PTR(-EINVAL);

	return ac97_ctrl->codecs[codec_num];
}

static void ac97_codec_release(struct device *dev)
{
	struct ac97_codec_device *adev;
	struct ac97_controller *ac97_ctrl;

	adev = to_ac97_device(dev);
	ac97_ctrl = adev->ac97_ctrl;
	ac97_ctrl->codecs[adev->num] = NULL;
	kfree(adev);
}

static int ac97_codec_add(struct ac97_controller *ac97_ctrl, int idx,
		   unsigned int vendor_id)
{
	struct ac97_codec_device *codec;
	int ret;

	codec = kzalloc(sizeof(*codec), GFP_KERNEL);
	if (!codec)
		return -ENOMEM;
	ac97_ctrl->codecs[idx] = codec;
	codec->vendor_id = vendor_id;
	codec->dev.release = ac97_codec_release;
	codec->dev.bus = &ac97_bus_type;
	codec->dev.parent = &ac97_ctrl->adap;
	codec->num = idx;
	codec->ac97_ctrl = ac97_ctrl;

	device_initialize(&codec->dev);
	dev_set_name(&codec->dev, "%s:%u", dev_name(ac97_ctrl->parent), idx);

	ret = device_add(&codec->dev);
	if (ret)
		goto err_free_codec;

	return 0;
err_free_codec:
	put_device(&codec->dev);
	kfree(codec);
	ac97_ctrl->codecs[idx] = NULL;

	return ret;
}

unsigned int snd_ac97_bus_scan_one(struct ac97_controller *adrv,
				   unsigned int codec_num)
{
	unsigned short vid1, vid2;
	int ret;

	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID1);
	vid1 = (ret & 0xffff);
	if (ret < 0)
		return 0;

	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID2);
	vid2 = (ret & 0xffff);
	if (ret < 0)
		return 0;

	dev_dbg(&adrv->adap, "%s(codec_num=%u): vendor_id=0x%08x\n",
		__func__, codec_num, AC97_ID(vid1, vid2));
	return AC97_ID(vid1, vid2);
}

static int ac97_bus_scan(struct ac97_controller *ac97_ctrl)
{
	int ret, i;
	unsigned int vendor_id;

	for (i = 0; i < AC97_BUS_MAX_CODECS; i++) {
		if (ac97_codec_find(ac97_ctrl, i))
			continue;
		if (!(ac97_ctrl->slots_available & BIT(i)))
			continue;
		vendor_id = snd_ac97_bus_scan_one(ac97_ctrl, i);
		if (!vendor_id)
			continue;

		ret = ac97_codec_add(ac97_ctrl, i, vendor_id);
		if (ret < 0)
			return ret;
	}
	return 0;
}

static int ac97_bus_reset(struct ac97_controller *ac97_ctrl)
{
	ac97_ctrl->ops->reset(ac97_ctrl);

	return 0;
}

/**
 * snd_ac97_codec_driver_register - register an AC97 codec driver
 * @dev: AC97 driver codec to register
 *
 * Register an AC97 codec driver to the ac97 bus driver, aka. the AC97 digital
 * controller.
 *
 * Returns 0 on success or error code
 */
int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv)
{
	drv->driver.bus = &ac97_bus_type;
	return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_register);

/**
 * snd_ac97_codec_driver_unregister - unregister an AC97 codec driver
 * @dev: AC97 codec driver to unregister
 *
 * Unregister a previously registered ac97 codec driver.
 */
void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_unregister);

/**
 * snd_ac97_codec_get_platdata - get platform_data
 * @adev: the ac97 codec device
 *
 * For legacy platforms, in order to have platform_data in codec drivers
 * available, while ac97 device are auto-created upon probe, this retrieves the
 * platdata which was setup on ac97 controller registration.
 *
 * Returns the platform data pointer
 */
void *snd_ac97_codec_get_platdata(const struct ac97_codec_device *adev)
{
	struct ac97_controller *ac97_ctrl = adev->ac97_ctrl;

	return ac97_ctrl->codecs_pdata[adev->num];
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_get_platdata);

static void ac97_ctrl_codecs_unregister(struct ac97_controller *ac97_ctrl)
{
	int i;

	for (i = 0; i < AC97_BUS_MAX_CODECS; i++)
		if (ac97_ctrl->codecs[i]) {
			ac97_ctrl->codecs[i]->ac97_ctrl = &ac97_unbound_ctrl;
			device_unregister(&ac97_ctrl->codecs[i]->dev);
		}
}

static ssize_t cold_reset_store(struct device *dev,
				struct device_attribute *attr, const char *buf,
				size_t len)
{
	struct ac97_controller *ac97_ctrl;

	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl = to_ac97_controller(dev);
	ac97_ctrl->ops->reset(ac97_ctrl);
	mutex_unlock(&ac97_controllers_mutex);
	return len;
}
static DEVICE_ATTR_WO(cold_reset);

static ssize_t warm_reset_store(struct device *dev,
				struct device_attribute *attr, const char *buf,
				size_t len)
{
	struct ac97_controller *ac97_ctrl;

	if (!dev)
		return -ENODEV;

	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl = to_ac97_controller(dev);
	ac97_ctrl->ops->warm_reset(ac97_ctrl);
	mutex_unlock(&ac97_controllers_mutex);
	return len;
}
static DEVICE_ATTR_WO(warm_reset);

static struct attribute *ac97_controller_device_attrs[] = {
	&dev_attr_cold_reset.attr,
	&dev_attr_warm_reset.attr,
	NULL
};

static struct attribute_group ac97_adapter_attr_group = {
	.name	= "ac97_operations",
	.attrs	= ac97_controller_device_attrs,
};

static const struct attribute_group *ac97_adapter_groups[] = {
	&ac97_adapter_attr_group,
	NULL,
};

static void ac97_del_adapter(struct ac97_controller *ac97_ctrl)
{
	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl_codecs_unregister(ac97_ctrl);
	list_del(&ac97_ctrl->controllers);
	mutex_unlock(&ac97_controllers_mutex);

	device_unregister(&ac97_ctrl->adap);
}

static void ac97_adapter_release(struct device *dev)
{
	struct ac97_controller *ac97_ctrl;

	ac97_ctrl = to_ac97_controller(dev);
	idr_remove(&ac97_adapter_idr, ac97_ctrl->nr);
	dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n",
		dev_name(ac97_ctrl->parent));
}

static const struct device_type ac97_adapter_type = {
	.groups		= ac97_adapter_groups,
	.release	= ac97_adapter_release,
};

static int ac97_add_adapter(struct ac97_controller *ac97_ctrl)
{
	int ret;

	mutex_lock(&ac97_controllers_mutex);
	ret = idr_alloc(&ac97_adapter_idr, ac97_ctrl, 0, 0, GFP_KERNEL);
	ac97_ctrl->nr = ret;
	if (ret >= 0) {
		dev_set_name(&ac97_ctrl->adap, "ac97-%d", ret);
		ac97_ctrl->adap.type = &ac97_adapter_type;
		ac97_ctrl->adap.parent = ac97_ctrl->parent;
		ret = device_register(&ac97_ctrl->adap);
		if (ret)
			put_device(&ac97_ctrl->adap);
	}
	if (!ret)
		list_add(&ac97_ctrl->controllers, &ac97_controllers);
	mutex_unlock(&ac97_controllers_mutex);

	if (!ret)
		dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n",
			dev_name(ac97_ctrl->parent));
	return ret;
}

/**
 * snd_ac97_controller_register - register an ac97 controller
 * @ops: the ac97 bus operations
 * @dev: the device providing the ac97 DC function
 * @slots_available: mask of the ac97 codecs that can be scanned and probed
 *                   bit0 => codec 0, bit1 => codec 1 ... bit 3 => codec 3
 *
 * Register a digital controller which can control up to 4 ac97 codecs. This is
 * the controller side of the AC97 AC-link, while the slave side are the codecs.
 *
 * Returns a valid controller upon success, negative pointer value upon error
 */
struct ac97_controller *snd_ac97_controller_register(
	const struct ac97_controller_ops *ops, struct device *dev,
	unsigned short slots_available, void **codecs_pdata)
{
	struct ac97_controller *ac97_ctrl;
	int ret, i;

	ac97_ctrl = kzalloc(sizeof(*ac97_ctrl), GFP_KERNEL);
	if (!ac97_ctrl)
		return ERR_PTR(-ENOMEM);

	for (i = 0; i < AC97_BUS_MAX_CODECS && codecs_pdata; i++)
		ac97_ctrl->codecs_pdata[i] = codecs_pdata[i];

	ac97_ctrl->ops = ops;
	ac97_ctrl->slots_available = slots_available;
	ac97_ctrl->parent = dev;
	ret = ac97_add_adapter(ac97_ctrl);

	if (ret)
		goto err;
	ac97_bus_reset(ac97_ctrl);
	ac97_bus_scan(ac97_ctrl);

	return ac97_ctrl;
err:
	kfree(ac97_ctrl);
	return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(snd_ac97_controller_register);

/**
 * snd_ac97_controller_unregister - unregister an ac97 controller
 * @ac97_ctrl: the device previously provided to ac97_controller_register()
 *
 */
void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
{
	ac97_del_adapter(ac97_ctrl);
}
EXPORT_SYMBOL_GPL(snd_ac97_controller_unregister);

#ifdef CONFIG_PM
static int ac97_pm_runtime_suspend(struct device *dev)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);
	int ret = pm_generic_runtime_suspend(dev);

	if (ret == 0 && dev->driver) {
		if (pm_runtime_is_irq_safe(dev))
			clk_disable(codec->clk);
		else
			clk_disable_unprepare(codec->clk);
	}

	return ret;
}

static int ac97_pm_runtime_resume(struct device *dev)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);
	int ret;

	if (dev->driver) {
		if (pm_runtime_is_irq_safe(dev))
			ret = clk_enable(codec->clk);
		else
			ret = clk_prepare_enable(codec->clk);
		if (ret)
			return ret;
	}

	return pm_generic_runtime_resume(dev);
}
#endif /* CONFIG_PM */

static const struct dev_pm_ops ac97_pm = {
	.suspend	= pm_generic_suspend,
	.resume		= pm_generic_resume,
	.freeze		= pm_generic_freeze,
	.thaw		= pm_generic_thaw,
	.poweroff	= pm_generic_poweroff,
	.restore	= pm_generic_restore,
	SET_RUNTIME_PM_OPS(
		ac97_pm_runtime_suspend,
		ac97_pm_runtime_resume,
		NULL)
};

static int ac97_get_enable_clk(struct ac97_codec_device *adev)
{
	int ret;

	adev->clk = clk_get(&adev->dev, "ac97_clk");
	if (IS_ERR(adev->clk))
		return PTR_ERR(adev->clk);

	ret = clk_prepare_enable(adev->clk);
	if (ret)
		clk_put(adev->clk);

	return ret;
}

static void ac97_put_disable_clk(struct ac97_codec_device *adev)
{
	clk_disable_unprepare(adev->clk);
	clk_put(adev->clk);
}

static ssize_t vendor_id_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);

	return sprintf(buf, "%08x", codec->vendor_id);
}
DEVICE_ATTR_RO(vendor_id);

static struct attribute *ac97_dev_attrs[] = {
	&dev_attr_vendor_id.attr,
	NULL,
};
ATTRIBUTE_GROUPS(ac97_dev);

static int ac97_bus_match(struct device *dev, struct device_driver *drv)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(drv);
	const struct ac97_id *id = adrv->id_table;
	int i = 0;

	if (adev->vendor_id == 0x0 || adev->vendor_id == 0xffffffff)
		return false;

	do {
		if (ac97_ids_match(id[i].id, adev->vendor_id, id[i].mask))
			return true;
	} while (id[i++].id);

	return false;
}

static int ac97_bus_probe(struct device *dev)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
	int ret;

	ret = ac97_get_enable_clk(adev);
	if (ret)
		return ret;

	pm_runtime_get_noresume(dev);
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);

	ret = adrv->probe(adev);
	if (ret == 0)
		return 0;

	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	pm_runtime_put_noidle(dev);
	ac97_put_disable_clk(adev);

	return ret;
}

static int ac97_bus_remove(struct device *dev)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
	int ret;

	ret = pm_runtime_get_sync(dev);
	if (ret)
		return ret;

	ret = adrv->remove(adev);
	pm_runtime_put_noidle(dev);
	if (ret == 0)
		ac97_put_disable_clk(adev);

	return ret;
}

static struct bus_type ac97_bus_type = {
	.name		= "ac97bus",
	.dev_groups	= ac97_dev_groups,
	.match		= ac97_bus_match,
	.pm		= &ac97_pm,
	.probe		= ac97_bus_probe,
	.remove		= ac97_bus_remove,
};

static int __init ac97_bus_init(void)
{
	return bus_register(&ac97_bus_type);
}
subsys_initcall(ac97_bus_init);

static void __exit ac97_bus_exit(void)
{
	bus_unregister(&ac97_bus_type);
}
module_exit(ac97_bus_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");