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torvalds
GitHub Repository: torvalds/linux
Path: blob/master/sound/i2c/other/ak4117.c
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1
// SPDX-License-Identifier: GPL-2.0-or-later
2
/*
3
* Routines for control of the AK4117 via 4-wire serial interface
4
* IEC958 (S/PDIF) receiver by Asahi Kasei
5
* Copyright (c) by Jaroslav Kysela <[email protected]>
6
*/
7
8
#include <linux/slab.h>
9
#include <linux/delay.h>
10
#include <linux/module.h>
11
#include <sound/core.h>
12
#include <sound/control.h>
13
#include <sound/pcm.h>
14
#include <sound/ak4117.h>
15
#include <sound/asoundef.h>
16
17
MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
18
MODULE_DESCRIPTION("AK4117 IEC958 (S/PDIF) receiver by Asahi Kasei");
19
MODULE_LICENSE("GPL");
20
21
#define AK4117_ADDR 0x00 /* fixed address */
22
23
static void snd_ak4117_timer(struct timer_list *t);
24
25
static void reg_write(struct ak4117 *ak4117, unsigned char reg, unsigned char val)
26
{
27
ak4117->write(ak4117->private_data, reg, val);
28
if (reg < sizeof(ak4117->regmap))
29
ak4117->regmap[reg] = val;
30
}
31
32
static inline unsigned char reg_read(struct ak4117 *ak4117, unsigned char reg)
33
{
34
return ak4117->read(ak4117->private_data, reg);
35
}
36
37
static void snd_ak4117_free(struct ak4117 *chip)
38
{
39
timer_shutdown_sync(&chip->timer);
40
kfree(chip);
41
}
42
43
static int snd_ak4117_dev_free(struct snd_device *device)
44
{
45
struct ak4117 *chip = device->device_data;
46
snd_ak4117_free(chip);
47
return 0;
48
}
49
50
int snd_ak4117_create(struct snd_card *card, ak4117_read_t *read, ak4117_write_t *write,
51
const unsigned char pgm[5], void *private_data, struct ak4117 **r_ak4117)
52
{
53
struct ak4117 *chip;
54
int err = 0;
55
unsigned char reg;
56
static const struct snd_device_ops ops = {
57
.dev_free = snd_ak4117_dev_free,
58
};
59
60
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
61
if (chip == NULL)
62
return -ENOMEM;
63
spin_lock_init(&chip->lock);
64
chip->card = card;
65
chip->read = read;
66
chip->write = write;
67
chip->private_data = private_data;
68
timer_setup(&chip->timer, snd_ak4117_timer, 0);
69
70
for (reg = 0; reg < 5; reg++)
71
chip->regmap[reg] = pgm[reg];
72
snd_ak4117_reinit(chip);
73
74
chip->rcs0 = reg_read(chip, AK4117_REG_RCS0) & ~(AK4117_QINT | AK4117_CINT | AK4117_STC);
75
chip->rcs1 = reg_read(chip, AK4117_REG_RCS1);
76
chip->rcs2 = reg_read(chip, AK4117_REG_RCS2);
77
78
err = snd_device_new(card, SNDRV_DEV_CODEC, chip, &ops);
79
if (err < 0)
80
goto __fail;
81
82
if (r_ak4117)
83
*r_ak4117 = chip;
84
return 0;
85
86
__fail:
87
snd_ak4117_free(chip);
88
return err;
89
}
90
91
void snd_ak4117_reg_write(struct ak4117 *chip, unsigned char reg, unsigned char mask, unsigned char val)
92
{
93
if (reg >= 5)
94
return;
95
reg_write(chip, reg, (chip->regmap[reg] & ~mask) | val);
96
}
97
98
void snd_ak4117_reinit(struct ak4117 *chip)
99
{
100
unsigned char old = chip->regmap[AK4117_REG_PWRDN], reg;
101
102
timer_delete(&chip->timer);
103
chip->init = 1;
104
/* bring the chip to reset state and powerdown state */
105
reg_write(chip, AK4117_REG_PWRDN, 0);
106
udelay(200);
107
/* release reset, but leave powerdown */
108
reg_write(chip, AK4117_REG_PWRDN, (old | AK4117_RST) & ~AK4117_PWN);
109
udelay(200);
110
for (reg = 1; reg < 5; reg++)
111
reg_write(chip, reg, chip->regmap[reg]);
112
/* release powerdown, everything is initialized now */
113
reg_write(chip, AK4117_REG_PWRDN, old | AK4117_RST | AK4117_PWN);
114
chip->init = 0;
115
mod_timer(&chip->timer, 1 + jiffies);
116
}
117
118
static unsigned int external_rate(unsigned char rcs1)
119
{
120
switch (rcs1 & (AK4117_FS0|AK4117_FS1|AK4117_FS2|AK4117_FS3)) {
121
case AK4117_FS_32000HZ: return 32000;
122
case AK4117_FS_44100HZ: return 44100;
123
case AK4117_FS_48000HZ: return 48000;
124
case AK4117_FS_88200HZ: return 88200;
125
case AK4117_FS_96000HZ: return 96000;
126
case AK4117_FS_176400HZ: return 176400;
127
case AK4117_FS_192000HZ: return 192000;
128
default: return 0;
129
}
130
}
131
132
static int snd_ak4117_in_error_info(struct snd_kcontrol *kcontrol,
133
struct snd_ctl_elem_info *uinfo)
134
{
135
uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
136
uinfo->count = 1;
137
uinfo->value.integer.min = 0;
138
uinfo->value.integer.max = LONG_MAX;
139
return 0;
140
}
141
142
static int snd_ak4117_in_error_get(struct snd_kcontrol *kcontrol,
143
struct snd_ctl_elem_value *ucontrol)
144
{
145
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
146
147
spin_lock_irq(&chip->lock);
148
ucontrol->value.integer.value[0] =
149
chip->errors[kcontrol->private_value];
150
chip->errors[kcontrol->private_value] = 0;
151
spin_unlock_irq(&chip->lock);
152
return 0;
153
}
154
155
#define snd_ak4117_in_bit_info snd_ctl_boolean_mono_info
156
157
static int snd_ak4117_in_bit_get(struct snd_kcontrol *kcontrol,
158
struct snd_ctl_elem_value *ucontrol)
159
{
160
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
161
unsigned char reg = kcontrol->private_value & 0xff;
162
unsigned char bit = (kcontrol->private_value >> 8) & 0xff;
163
unsigned char inv = (kcontrol->private_value >> 31) & 1;
164
165
ucontrol->value.integer.value[0] = ((reg_read(chip, reg) & (1 << bit)) ? 1 : 0) ^ inv;
166
return 0;
167
}
168
169
static int snd_ak4117_rx_info(struct snd_kcontrol *kcontrol,
170
struct snd_ctl_elem_info *uinfo)
171
{
172
uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
173
uinfo->count = 1;
174
uinfo->value.integer.min = 0;
175
uinfo->value.integer.max = 1;
176
return 0;
177
}
178
179
static int snd_ak4117_rx_get(struct snd_kcontrol *kcontrol,
180
struct snd_ctl_elem_value *ucontrol)
181
{
182
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
183
184
ucontrol->value.integer.value[0] = (chip->regmap[AK4117_REG_IO] & AK4117_IPS) ? 1 : 0;
185
return 0;
186
}
187
188
static int snd_ak4117_rx_put(struct snd_kcontrol *kcontrol,
189
struct snd_ctl_elem_value *ucontrol)
190
{
191
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
192
int change;
193
u8 old_val;
194
195
spin_lock_irq(&chip->lock);
196
old_val = chip->regmap[AK4117_REG_IO];
197
change = !!ucontrol->value.integer.value[0] != ((old_val & AK4117_IPS) ? 1 : 0);
198
if (change)
199
reg_write(chip, AK4117_REG_IO, (old_val & ~AK4117_IPS) | (ucontrol->value.integer.value[0] ? AK4117_IPS : 0));
200
spin_unlock_irq(&chip->lock);
201
return change;
202
}
203
204
static int snd_ak4117_rate_info(struct snd_kcontrol *kcontrol,
205
struct snd_ctl_elem_info *uinfo)
206
{
207
uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
208
uinfo->count = 1;
209
uinfo->value.integer.min = 0;
210
uinfo->value.integer.max = 192000;
211
return 0;
212
}
213
214
static int snd_ak4117_rate_get(struct snd_kcontrol *kcontrol,
215
struct snd_ctl_elem_value *ucontrol)
216
{
217
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
218
219
ucontrol->value.integer.value[0] = external_rate(reg_read(chip, AK4117_REG_RCS1));
220
return 0;
221
}
222
223
static int snd_ak4117_spdif_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
224
{
225
uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
226
uinfo->count = 1;
227
return 0;
228
}
229
230
static int snd_ak4117_spdif_get(struct snd_kcontrol *kcontrol,
231
struct snd_ctl_elem_value *ucontrol)
232
{
233
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
234
unsigned i;
235
236
for (i = 0; i < AK4117_REG_RXCSB_SIZE; i++)
237
ucontrol->value.iec958.status[i] = reg_read(chip, AK4117_REG_RXCSB0 + i);
238
return 0;
239
}
240
241
static int snd_ak4117_spdif_mask_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
242
{
243
uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
244
uinfo->count = 1;
245
return 0;
246
}
247
248
static int snd_ak4117_spdif_mask_get(struct snd_kcontrol *kcontrol,
249
struct snd_ctl_elem_value *ucontrol)
250
{
251
memset(ucontrol->value.iec958.status, 0xff, AK4117_REG_RXCSB_SIZE);
252
return 0;
253
}
254
255
static int snd_ak4117_spdif_pinfo(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
256
{
257
uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
258
uinfo->value.integer.min = 0;
259
uinfo->value.integer.max = 0xffff;
260
uinfo->count = 4;
261
return 0;
262
}
263
264
static int snd_ak4117_spdif_pget(struct snd_kcontrol *kcontrol,
265
struct snd_ctl_elem_value *ucontrol)
266
{
267
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
268
unsigned short tmp;
269
270
ucontrol->value.integer.value[0] = 0xf8f2;
271
ucontrol->value.integer.value[1] = 0x4e1f;
272
tmp = reg_read(chip, AK4117_REG_Pc0) | (reg_read(chip, AK4117_REG_Pc1) << 8);
273
ucontrol->value.integer.value[2] = tmp;
274
tmp = reg_read(chip, AK4117_REG_Pd0) | (reg_read(chip, AK4117_REG_Pd1) << 8);
275
ucontrol->value.integer.value[3] = tmp;
276
return 0;
277
}
278
279
static int snd_ak4117_spdif_qinfo(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
280
{
281
uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
282
uinfo->count = AK4117_REG_QSUB_SIZE;
283
return 0;
284
}
285
286
static int snd_ak4117_spdif_qget(struct snd_kcontrol *kcontrol,
287
struct snd_ctl_elem_value *ucontrol)
288
{
289
struct ak4117 *chip = snd_kcontrol_chip(kcontrol);
290
unsigned i;
291
292
for (i = 0; i < AK4117_REG_QSUB_SIZE; i++)
293
ucontrol->value.bytes.data[i] = reg_read(chip, AK4117_REG_QSUB_ADDR + i);
294
return 0;
295
}
296
297
/* Don't forget to change AK4117_CONTROLS define!!! */
298
static const struct snd_kcontrol_new snd_ak4117_iec958_controls[] = {
299
{
300
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
301
.name = "IEC958 Parity Errors",
302
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
303
.info = snd_ak4117_in_error_info,
304
.get = snd_ak4117_in_error_get,
305
.private_value = AK4117_PARITY_ERRORS,
306
},
307
{
308
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
309
.name = "IEC958 V-Bit Errors",
310
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
311
.info = snd_ak4117_in_error_info,
312
.get = snd_ak4117_in_error_get,
313
.private_value = AK4117_V_BIT_ERRORS,
314
},
315
{
316
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
317
.name = "IEC958 C-CRC Errors",
318
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
319
.info = snd_ak4117_in_error_info,
320
.get = snd_ak4117_in_error_get,
321
.private_value = AK4117_CCRC_ERRORS,
322
},
323
{
324
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
325
.name = "IEC958 Q-CRC Errors",
326
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
327
.info = snd_ak4117_in_error_info,
328
.get = snd_ak4117_in_error_get,
329
.private_value = AK4117_QCRC_ERRORS,
330
},
331
{
332
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
333
.name = "IEC958 External Rate",
334
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
335
.info = snd_ak4117_rate_info,
336
.get = snd_ak4117_rate_get,
337
},
338
{
339
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
340
.name = SNDRV_CTL_NAME_IEC958("",CAPTURE,MASK),
341
.access = SNDRV_CTL_ELEM_ACCESS_READ,
342
.info = snd_ak4117_spdif_mask_info,
343
.get = snd_ak4117_spdif_mask_get,
344
},
345
{
346
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
347
.name = SNDRV_CTL_NAME_IEC958("",CAPTURE,DEFAULT),
348
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
349
.info = snd_ak4117_spdif_info,
350
.get = snd_ak4117_spdif_get,
351
},
352
{
353
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
354
.name = "IEC958 Preamble Capture Default",
355
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
356
.info = snd_ak4117_spdif_pinfo,
357
.get = snd_ak4117_spdif_pget,
358
},
359
{
360
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
361
.name = "IEC958 Q-subcode Capture Default",
362
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
363
.info = snd_ak4117_spdif_qinfo,
364
.get = snd_ak4117_spdif_qget,
365
},
366
{
367
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
368
.name = "IEC958 Audio",
369
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
370
.info = snd_ak4117_in_bit_info,
371
.get = snd_ak4117_in_bit_get,
372
.private_value = (1<<31) | (3<<8) | AK4117_REG_RCS0,
373
},
374
{
375
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
376
.name = "IEC958 Non-PCM Bitstream",
377
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
378
.info = snd_ak4117_in_bit_info,
379
.get = snd_ak4117_in_bit_get,
380
.private_value = (5<<8) | AK4117_REG_RCS1,
381
},
382
{
383
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
384
.name = "IEC958 DTS Bitstream",
385
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
386
.info = snd_ak4117_in_bit_info,
387
.get = snd_ak4117_in_bit_get,
388
.private_value = (6<<8) | AK4117_REG_RCS1,
389
},
390
{
391
.iface = SNDRV_CTL_ELEM_IFACE_PCM,
392
.name = "AK4117 Input Select",
393
.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_WRITE,
394
.info = snd_ak4117_rx_info,
395
.get = snd_ak4117_rx_get,
396
.put = snd_ak4117_rx_put,
397
}
398
};
399
400
int snd_ak4117_build(struct ak4117 *ak4117, struct snd_pcm_substream *cap_substream)
401
{
402
struct snd_kcontrol *kctl;
403
unsigned int idx;
404
int err;
405
406
if (snd_BUG_ON(!cap_substream))
407
return -EINVAL;
408
ak4117->substream = cap_substream;
409
for (idx = 0; idx < AK4117_CONTROLS; idx++) {
410
kctl = snd_ctl_new1(&snd_ak4117_iec958_controls[idx], ak4117);
411
if (kctl == NULL)
412
return -ENOMEM;
413
kctl->id.device = cap_substream->pcm->device;
414
kctl->id.subdevice = cap_substream->number;
415
err = snd_ctl_add(ak4117->card, kctl);
416
if (err < 0)
417
return err;
418
ak4117->kctls[idx] = kctl;
419
}
420
return 0;
421
}
422
423
int snd_ak4117_external_rate(struct ak4117 *ak4117)
424
{
425
unsigned char rcs1;
426
427
rcs1 = reg_read(ak4117, AK4117_REG_RCS1);
428
return external_rate(rcs1);
429
}
430
431
int snd_ak4117_check_rate_and_errors(struct ak4117 *ak4117, unsigned int flags)
432
{
433
struct snd_pcm_runtime *runtime = ak4117->substream ? ak4117->substream->runtime : NULL;
434
unsigned long _flags;
435
int res = 0;
436
unsigned char rcs0, rcs1, rcs2;
437
unsigned char c0, c1;
438
439
rcs1 = reg_read(ak4117, AK4117_REG_RCS1);
440
if (flags & AK4117_CHECK_NO_STAT)
441
goto __rate;
442
rcs0 = reg_read(ak4117, AK4117_REG_RCS0);
443
rcs2 = reg_read(ak4117, AK4117_REG_RCS2);
444
spin_lock_irqsave(&ak4117->lock, _flags);
445
if (rcs0 & AK4117_PAR)
446
ak4117->errors[AK4117_PARITY_ERRORS]++;
447
if (rcs0 & AK4117_V)
448
ak4117->errors[AK4117_V_BIT_ERRORS]++;
449
if (rcs2 & AK4117_CCRC)
450
ak4117->errors[AK4117_CCRC_ERRORS]++;
451
if (rcs2 & AK4117_QCRC)
452
ak4117->errors[AK4117_QCRC_ERRORS]++;
453
c0 = (ak4117->rcs0 & (AK4117_QINT | AK4117_CINT | AK4117_STC | AK4117_AUDION | AK4117_AUTO | AK4117_UNLCK)) ^
454
(rcs0 & (AK4117_QINT | AK4117_CINT | AK4117_STC | AK4117_AUDION | AK4117_AUTO | AK4117_UNLCK));
455
c1 = (ak4117->rcs1 & (AK4117_DTSCD | AK4117_NPCM | AK4117_PEM | 0x0f)) ^
456
(rcs1 & (AK4117_DTSCD | AK4117_NPCM | AK4117_PEM | 0x0f));
457
ak4117->rcs0 = rcs0 & ~(AK4117_QINT | AK4117_CINT | AK4117_STC);
458
ak4117->rcs1 = rcs1;
459
ak4117->rcs2 = rcs2;
460
spin_unlock_irqrestore(&ak4117->lock, _flags);
461
462
if (rcs0 & AK4117_PAR)
463
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[0]->id);
464
if (rcs0 & AK4117_V)
465
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[1]->id);
466
if (rcs2 & AK4117_CCRC)
467
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[2]->id);
468
if (rcs2 & AK4117_QCRC)
469
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[3]->id);
470
471
/* rate change */
472
if (c1 & 0x0f)
473
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[4]->id);
474
475
if ((c1 & AK4117_PEM) | (c0 & AK4117_CINT))
476
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[6]->id);
477
if (c0 & AK4117_QINT)
478
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[8]->id);
479
480
if (c0 & AK4117_AUDION)
481
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[9]->id);
482
if (c1 & AK4117_NPCM)
483
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[10]->id);
484
if (c1 & AK4117_DTSCD)
485
snd_ctl_notify(ak4117->card, SNDRV_CTL_EVENT_MASK_VALUE, &ak4117->kctls[11]->id);
486
487
if (ak4117->change_callback && (c0 | c1) != 0)
488
ak4117->change_callback(ak4117, c0, c1);
489
490
__rate:
491
/* compare rate */
492
res = external_rate(rcs1);
493
if (!(flags & AK4117_CHECK_NO_RATE) && runtime && runtime->rate != res) {
494
snd_pcm_stream_lock_irqsave(ak4117->substream, _flags);
495
if (snd_pcm_running(ak4117->substream)) {
496
snd_pcm_stop(ak4117->substream, SNDRV_PCM_STATE_DRAINING);
497
wake_up(&runtime->sleep);
498
res = 1;
499
}
500
snd_pcm_stream_unlock_irqrestore(ak4117->substream, _flags);
501
}
502
return res;
503
}
504
505
static void snd_ak4117_timer(struct timer_list *t)
506
{
507
struct ak4117 *chip = timer_container_of(chip, t, timer);
508
509
if (chip->init)
510
return;
511
snd_ak4117_check_rate_and_errors(chip, 0);
512
mod_timer(&chip->timer, 1 + jiffies);
513
}
514
515
EXPORT_SYMBOL(snd_ak4117_create);
516
EXPORT_SYMBOL(snd_ak4117_reg_write);
517
EXPORT_SYMBOL(snd_ak4117_reinit);
518
EXPORT_SYMBOL(snd_ak4117_build);
519
EXPORT_SYMBOL(snd_ak4117_external_rate);
520
EXPORT_SYMBOL(snd_ak4117_check_rate_and_errors);
521
522