2 * CS4270 ALSA SoC (ASoC) codec driver
4 * Author: Timur Tabi <timur@freescale.com>
6 * Copyright 2007-2009 Freescale Semiconductor, Inc. This file is licensed
7 * under the terms of the GNU General Public License version 2. This
8 * program is licensed "as is" without any warranty of any kind, whether
11 * This is an ASoC device driver for the Cirrus Logic CS4270 codec.
13 * Current features/limitations:
15 * 1) Software mode is supported. Stand-alone mode is not supported.
16 * 2) Only I2C is supported, not SPI
17 * 3) Only Master mode is supported, not Slave.
18 * 4) The machine driver's 'startup' function must call
19 * cs4270_set_dai_sysclk() with the value of MCLK.
20 * 5) Only I2S and left-justified modes are supported
21 * 6) Power management is not supported
22 * 7) The only supported control is volume and hardware mute (if enabled)
25 #include <linux/module.h>
26 #include <linux/platform_device.h>
27 #include <sound/core.h>
28 #include <sound/soc.h>
29 #include <sound/initval.h>
30 #include <linux/i2c.h>
35 * The codec isn't really big-endian or little-endian, since the I2S
36 * interface requires data to be sent serially with the MSbit first.
37 * However, to support BE and LE I2S devices, we specify both here. That
38 * way, ALSA will always match the bit patterns.
40 #define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8 | \
41 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE | \
42 SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S18_3BE | \
43 SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S20_3BE | \
44 SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | \
45 SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE)
47 /* CS4270 registers addresses */
48 #define CS4270_CHIPID 0x01 /* Chip ID */
49 #define CS4270_PWRCTL 0x02 /* Power Control */
50 #define CS4270_MODE 0x03 /* Mode Control */
51 #define CS4270_FORMAT 0x04 /* Serial Format, ADC/DAC Control */
52 #define CS4270_TRANS 0x05 /* Transition Control */
53 #define CS4270_MUTE 0x06 /* Mute Control */
54 #define CS4270_VOLA 0x07 /* DAC Channel A Volume Control */
55 #define CS4270_VOLB 0x08 /* DAC Channel B Volume Control */
57 #define CS4270_FIRSTREG 0x01
58 #define CS4270_LASTREG 0x08
59 #define CS4270_NUMREGS (CS4270_LASTREG - CS4270_FIRSTREG + 1)
61 /* Bit masks for the CS4270 registers */
62 #define CS4270_CHIPID_ID 0xF0
63 #define CS4270_CHIPID_REV 0x0F
64 #define CS4270_PWRCTL_FREEZE 0x80
65 #define CS4270_PWRCTL_PDN_ADC 0x20
66 #define CS4270_PWRCTL_PDN_DAC 0x02
67 #define CS4270_PWRCTL_PDN 0x01
68 #define CS4270_MODE_SPEED_MASK 0x30
69 #define CS4270_MODE_1X 0x00
70 #define CS4270_MODE_2X 0x10
71 #define CS4270_MODE_4X 0x20
72 #define CS4270_MODE_SLAVE 0x30
73 #define CS4270_MODE_DIV_MASK 0x0E
74 #define CS4270_MODE_DIV1 0x00
75 #define CS4270_MODE_DIV15 0x02
76 #define CS4270_MODE_DIV2 0x04
77 #define CS4270_MODE_DIV3 0x06
78 #define CS4270_MODE_DIV4 0x08
79 #define CS4270_MODE_POPGUARD 0x01
80 #define CS4270_FORMAT_FREEZE_A 0x80
81 #define CS4270_FORMAT_FREEZE_B 0x40
82 #define CS4270_FORMAT_LOOPBACK 0x20
83 #define CS4270_FORMAT_DAC_MASK 0x18
84 #define CS4270_FORMAT_DAC_LJ 0x00
85 #define CS4270_FORMAT_DAC_I2S 0x08
86 #define CS4270_FORMAT_DAC_RJ16 0x18
87 #define CS4270_FORMAT_DAC_RJ24 0x10
88 #define CS4270_FORMAT_ADC_MASK 0x01
89 #define CS4270_FORMAT_ADC_LJ 0x00
90 #define CS4270_FORMAT_ADC_I2S 0x01
91 #define CS4270_TRANS_ONE_VOL 0x80
92 #define CS4270_TRANS_SOFT 0x40
93 #define CS4270_TRANS_ZERO 0x20
94 #define CS4270_TRANS_INV_ADC_A 0x08
95 #define CS4270_TRANS_INV_ADC_B 0x10
96 #define CS4270_TRANS_INV_DAC_A 0x02
97 #define CS4270_TRANS_INV_DAC_B 0x04
98 #define CS4270_TRANS_DEEMPH 0x01
99 #define CS4270_MUTE_AUTO 0x20
100 #define CS4270_MUTE_ADC_A 0x08
101 #define CS4270_MUTE_ADC_B 0x10
102 #define CS4270_MUTE_POLARITY 0x04
103 #define CS4270_MUTE_DAC_A 0x01
104 #define CS4270_MUTE_DAC_B 0x02
106 /* Private data for the CS4270 */
107 struct cs4270_private
{
108 struct snd_soc_codec codec
;
109 u8 reg_cache
[CS4270_NUMREGS
];
110 unsigned int mclk
; /* Input frequency of the MCLK pin */
111 unsigned int mode
; /* The mode (I2S or left-justified) */
115 * struct cs4270_mode_ratios - clock ratio tables
116 * @ratio: the ratio of MCLK to the sample rate
117 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
119 * @mclk: the Ratio Select bits to set in the Mode Control register for this
122 * The data for this chart is taken from Table 5 of the CS4270 reference
125 * This table is used to determine how to program the Mode Control register.
126 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
127 * rates the CS4270 currently supports.
129 * @speed_mode is the corresponding bit pattern to be written to the
130 * MODE bits of the Mode Control Register
132 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
133 * the Mode Control Register.
135 * In situations where a single ratio is represented by multiple speed
136 * modes, we favor the slowest speed. E.g, for a ratio of 128, we pick
137 * double-speed instead of quad-speed. However, the CS4270 errata states
138 * that divide-By-1.5 can cause failures, so we avoid that mode where
141 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
142 * work if Vd is 3.3V. If this effects you, select the
143 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
144 * never select any sample rates that require divide-by-1.5.
146 struct cs4270_mode_ratios
{
152 static struct cs4270_mode_ratios cs4270_mode_ratios
[] = {
153 {64, CS4270_MODE_4X
, CS4270_MODE_DIV1
},
154 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
155 {96, CS4270_MODE_4X
, CS4270_MODE_DIV15
},
157 {128, CS4270_MODE_2X
, CS4270_MODE_DIV1
},
158 {192, CS4270_MODE_4X
, CS4270_MODE_DIV3
},
159 {256, CS4270_MODE_1X
, CS4270_MODE_DIV1
},
160 {384, CS4270_MODE_2X
, CS4270_MODE_DIV3
},
161 {512, CS4270_MODE_1X
, CS4270_MODE_DIV2
},
162 {768, CS4270_MODE_1X
, CS4270_MODE_DIV3
},
163 {1024, CS4270_MODE_1X
, CS4270_MODE_DIV4
}
166 /* The number of MCLK/LRCK ratios supported by the CS4270 */
167 #define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
170 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
171 * @codec_dai: the codec DAI
172 * @clk_id: the clock ID (ignored)
173 * @freq: the MCLK input frequency
174 * @dir: the clock direction (ignored)
176 * This function is used to tell the codec driver what the input MCLK
179 * The value of MCLK is used to determine which sample rates are supported
180 * by the CS4270. The ratio of MCLK / Fs must be equal to one of nine
181 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
183 * This function calculates the nine ratios and determines which ones match
184 * a standard sample rate. If there's a match, then it is added to the list
185 * of supported sample rates.
187 * This function must be called by the machine driver's 'startup' function,
188 * otherwise the list of supported sample rates will not be available in
191 static int cs4270_set_dai_sysclk(struct snd_soc_dai
*codec_dai
,
192 int clk_id
, unsigned int freq
, int dir
)
194 struct snd_soc_codec
*codec
= codec_dai
->codec
;
195 struct cs4270_private
*cs4270
= codec
->private_data
;
196 unsigned int rates
= 0;
197 unsigned int rate_min
= -1;
198 unsigned int rate_max
= 0;
203 for (i
= 0; i
< NUM_MCLK_RATIOS
; i
++) {
204 unsigned int rate
= freq
/ cs4270_mode_ratios
[i
].ratio
;
205 rates
|= snd_pcm_rate_to_rate_bit(rate
);
211 /* FIXME: soc should support a rate list */
212 rates
&= ~SNDRV_PCM_RATE_KNOT
;
215 dev_err(codec
->dev
, "could not find a valid sample rate\n");
219 codec_dai
->playback
.rates
= rates
;
220 codec_dai
->playback
.rate_min
= rate_min
;
221 codec_dai
->playback
.rate_max
= rate_max
;
223 codec_dai
->capture
.rates
= rates
;
224 codec_dai
->capture
.rate_min
= rate_min
;
225 codec_dai
->capture
.rate_max
= rate_max
;
231 * cs4270_set_dai_fmt - configure the codec for the selected audio format
232 * @codec_dai: the codec DAI
233 * @format: a SND_SOC_DAIFMT_x value indicating the data format
235 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
238 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
239 * SND_SOC_DAIFMT_LEFT_J. The CS4270 codec also supports right-justified
240 * data for playback only, but ASoC currently does not support different
241 * formats for playback vs. record.
243 static int cs4270_set_dai_fmt(struct snd_soc_dai
*codec_dai
,
246 struct snd_soc_codec
*codec
= codec_dai
->codec
;
247 struct cs4270_private
*cs4270
= codec
->private_data
;
250 switch (format
& SND_SOC_DAIFMT_FORMAT_MASK
) {
251 case SND_SOC_DAIFMT_I2S
:
252 case SND_SOC_DAIFMT_LEFT_J
:
253 cs4270
->mode
= format
& SND_SOC_DAIFMT_FORMAT_MASK
;
256 dev_err(codec
->dev
, "invalid dai format\n");
264 * cs4270_fill_cache - pre-fill the CS4270 register cache.
265 * @codec: the codec for this CS4270
267 * This function fills in the CS4270 register cache by reading the register
268 * values from the hardware.
270 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
271 * After the initial read to pre-fill the cache, the CS4270 never updates
272 * the register values, so we won't have a cache coherency problem.
274 * We use the auto-increment feature of the CS4270 to read all registers in
277 static int cs4270_fill_cache(struct snd_soc_codec
*codec
)
279 u8
*cache
= codec
->reg_cache
;
280 struct i2c_client
*i2c_client
= codec
->control_data
;
283 length
= i2c_smbus_read_i2c_block_data(i2c_client
,
284 CS4270_FIRSTREG
| 0x80, CS4270_NUMREGS
, cache
);
286 if (length
!= CS4270_NUMREGS
) {
287 dev_err(codec
->dev
, "i2c read failure, addr=0x%x\n",
296 * cs4270_read_reg_cache - read from the CS4270 register cache.
297 * @codec: the codec for this CS4270
298 * @reg: the register to read
300 * This function returns the value for a given register. It reads only from
301 * the register cache, not the hardware itself.
303 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
304 * After the initial read to pre-fill the cache, the CS4270 never updates
305 * the register values, so we won't have a cache coherency problem.
307 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec
*codec
,
310 u8
*cache
= codec
->reg_cache
;
312 if ((reg
< CS4270_FIRSTREG
) || (reg
> CS4270_LASTREG
))
315 return cache
[reg
- CS4270_FIRSTREG
];
319 * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
320 * @codec: the codec for this CS4270
321 * @reg: the register to write
322 * @value: the value to write to the register
324 * This function writes the given value to the given CS4270 register, and
325 * also updates the register cache.
327 * Note that we don't use the hw_write function pointer of snd_soc_codec.
328 * That's because it's too clunky: the hw_write_t prototype does not match
329 * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
331 static int cs4270_i2c_write(struct snd_soc_codec
*codec
, unsigned int reg
,
334 u8
*cache
= codec
->reg_cache
;
336 if ((reg
< CS4270_FIRSTREG
) || (reg
> CS4270_LASTREG
))
339 /* Only perform an I2C operation if the new value is different */
340 if (cache
[reg
- CS4270_FIRSTREG
] != value
) {
341 struct i2c_client
*client
= codec
->control_data
;
342 if (i2c_smbus_write_byte_data(client
, reg
, value
)) {
343 dev_err(codec
->dev
, "i2c write failed\n");
347 /* We've written to the hardware, so update the cache */
348 cache
[reg
- CS4270_FIRSTREG
] = value
;
355 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
356 * @substream: the audio stream
357 * @params: the hardware parameters to set
358 * @dai: the SOC DAI (ignored)
360 * This function programs the hardware with the values provided.
361 * Specifically, the sample rate and the data format.
363 * The .ops functions are used to provide board-specific data, like input
364 * frequencies, to this driver. This function takes that information,
365 * combines it with the hardware parameters provided, and programs the
366 * hardware accordingly.
368 static int cs4270_hw_params(struct snd_pcm_substream
*substream
,
369 struct snd_pcm_hw_params
*params
,
370 struct snd_soc_dai
*dai
)
372 struct snd_soc_pcm_runtime
*rtd
= substream
->private_data
;
373 struct snd_soc_device
*socdev
= rtd
->socdev
;
374 struct snd_soc_codec
*codec
= socdev
->card
->codec
;
375 struct cs4270_private
*cs4270
= codec
->private_data
;
382 /* Figure out which MCLK/LRCK ratio to use */
384 rate
= params_rate(params
); /* Sampling rate, in Hz */
385 ratio
= cs4270
->mclk
/ rate
; /* MCLK/LRCK ratio */
387 for (i
= 0; i
< NUM_MCLK_RATIOS
; i
++) {
388 if (cs4270_mode_ratios
[i
].ratio
== ratio
)
392 if (i
== NUM_MCLK_RATIOS
) {
393 /* We did not find a matching ratio */
394 dev_err(codec
->dev
, "could not find matching ratio\n");
398 /* Set the sample rate */
400 reg
= snd_soc_read(codec
, CS4270_MODE
);
401 reg
&= ~(CS4270_MODE_SPEED_MASK
| CS4270_MODE_DIV_MASK
);
402 reg
|= cs4270_mode_ratios
[i
].speed_mode
| cs4270_mode_ratios
[i
].mclk
;
404 ret
= snd_soc_write(codec
, CS4270_MODE
, reg
);
406 dev_err(codec
->dev
, "i2c write failed\n");
410 /* Set the DAI format */
412 reg
= snd_soc_read(codec
, CS4270_FORMAT
);
413 reg
&= ~(CS4270_FORMAT_DAC_MASK
| CS4270_FORMAT_ADC_MASK
);
415 switch (cs4270
->mode
) {
416 case SND_SOC_DAIFMT_I2S
:
417 reg
|= CS4270_FORMAT_DAC_I2S
| CS4270_FORMAT_ADC_I2S
;
419 case SND_SOC_DAIFMT_LEFT_J
:
420 reg
|= CS4270_FORMAT_DAC_LJ
| CS4270_FORMAT_ADC_LJ
;
423 dev_err(codec
->dev
, "unknown dai format\n");
427 ret
= snd_soc_write(codec
, CS4270_FORMAT
, reg
);
429 dev_err(codec
->dev
, "i2c write failed\n");
437 * cs4270_mute - enable/disable the CS4270 external mute
439 * @mute: 0 = disable mute, 1 = enable mute
441 * This function toggles the mute bits in the MUTE register. The CS4270's
442 * mute capability is intended for external muting circuitry, so if the
443 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
444 * then this function will do nothing.
446 static int cs4270_mute(struct snd_soc_dai
*dai
, int mute
)
448 struct snd_soc_codec
*codec
= dai
->codec
;
451 reg6
= snd_soc_read(codec
, CS4270_MUTE
);
454 reg6
|= CS4270_MUTE_DAC_A
| CS4270_MUTE_DAC_B
;
456 reg6
&= ~(CS4270_MUTE_DAC_A
| CS4270_MUTE_DAC_B
);
458 return snd_soc_write(codec
, CS4270_MUTE
, reg6
);
461 /* A list of non-DAPM controls that the CS4270 supports */
462 static const struct snd_kcontrol_new cs4270_snd_controls
[] = {
463 SOC_DOUBLE_R("Master Playback Volume",
464 CS4270_VOLA
, CS4270_VOLB
, 0, 0xFF, 1),
465 SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT
, 5, 1, 0),
466 SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS
, 6, 1, 0),
467 SOC_SINGLE("Zero Cross Switch", CS4270_TRANS
, 5, 1, 0),
468 SOC_SINGLE("Popguard Switch", CS4270_MODE
, 0, 1, 1),
469 SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE
, 5, 1, 0),
470 SOC_DOUBLE("Master Capture Switch", CS4270_MUTE
, 3, 4, 1, 0)
474 * cs4270_codec - global variable to store codec for the ASoC probe function
476 * If struct i2c_driver had a private_data field, we wouldn't need to use
477 * cs4270_codec. This is the only way to pass the codec structure from
478 * cs4270_i2c_probe() to cs4270_probe(). Unfortunately, there is no good
479 * way to synchronize these two functions. cs4270_i2c_probe() can be called
480 * multiple times before cs4270_probe() is called even once. So for now, we
481 * also only allow cs4270_i2c_probe() to be run once. That means that we do
482 * not support more than one cs4270 device in the system, at least for now.
484 static struct snd_soc_codec
*cs4270_codec
;
486 struct snd_soc_dai cs4270_dai
= {
489 .stream_name
= "Playback",
493 .formats
= CS4270_FORMATS
,
496 .stream_name
= "Capture",
500 .formats
= CS4270_FORMATS
,
503 .hw_params
= cs4270_hw_params
,
504 .set_sysclk
= cs4270_set_dai_sysclk
,
505 .set_fmt
= cs4270_set_dai_fmt
,
506 .digital_mute
= cs4270_mute
,
509 EXPORT_SYMBOL_GPL(cs4270_dai
);
512 * cs4270_probe - ASoC probe function
513 * @pdev: platform device
515 * This function is called when ASoC has all the pieces it needs to
516 * instantiate a sound driver.
518 static int cs4270_probe(struct platform_device
*pdev
)
520 struct snd_soc_device
*socdev
= platform_get_drvdata(pdev
);
521 struct snd_soc_codec
*codec
= cs4270_codec
;
525 /* Connect the codec to the socdev. snd_soc_new_pcms() needs this. */
526 socdev
->card
->codec
= codec
;
529 ret
= snd_soc_new_pcms(socdev
, SNDRV_DEFAULT_IDX1
, SNDRV_DEFAULT_STR1
);
531 dev_err(codec
->dev
, "failed to create pcms\n");
535 /* Add the non-DAPM controls */
536 for (i
= 0; i
< ARRAY_SIZE(cs4270_snd_controls
); i
++) {
537 struct snd_kcontrol
*kctrl
;
539 kctrl
= snd_soc_cnew(&cs4270_snd_controls
[i
], codec
, NULL
);
541 dev_err(codec
->dev
, "error creating control '%s'\n",
542 cs4270_snd_controls
[i
].name
);
544 goto error_free_pcms
;
547 ret
= snd_ctl_add(codec
->card
, kctrl
);
549 dev_err(codec
->dev
, "error adding control '%s'\n",
550 cs4270_snd_controls
[i
].name
);
551 goto error_free_pcms
;
555 /* And finally, register the socdev */
556 ret
= snd_soc_init_card(socdev
);
558 dev_err(codec
->dev
, "failed to register card\n");
559 goto error_free_pcms
;
565 snd_soc_free_pcms(socdev
);
571 * cs4270_remove - ASoC remove function
572 * @pdev: platform device
574 * This function is the counterpart to cs4270_probe().
576 static int cs4270_remove(struct platform_device
*pdev
)
578 struct snd_soc_device
*socdev
= platform_get_drvdata(pdev
);
580 snd_soc_free_pcms(socdev
);
586 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
587 * @i2c_client: the I2C client object
588 * @id: the I2C device ID (ignored)
590 * This function is called whenever the I2C subsystem finds a device that
591 * matches the device ID given via a prior call to i2c_add_driver().
593 static int cs4270_i2c_probe(struct i2c_client
*i2c_client
,
594 const struct i2c_device_id
*id
)
596 struct snd_soc_codec
*codec
;
597 struct cs4270_private
*cs4270
;
601 /* For now, we only support one cs4270 device in the system. See the
602 * comment for cs4270_codec.
605 dev_err(&i2c_client
->dev
, "ignoring CS4270 at addr %X\n",
607 dev_err(&i2c_client
->dev
, "only one per board allowed\n");
608 /* Should we return something other than ENODEV here? */
612 /* Verify that we have a CS4270 */
614 ret
= i2c_smbus_read_byte_data(i2c_client
, CS4270_CHIPID
);
616 dev_err(&i2c_client
->dev
, "failed to read i2c at addr %X\n",
620 /* The top four bits of the chip ID should be 1100. */
621 if ((ret
& 0xF0) != 0xC0) {
622 dev_err(&i2c_client
->dev
, "device at addr %X is not a CS4270\n",
627 dev_info(&i2c_client
->dev
, "found device at i2c address %X\n",
629 dev_info(&i2c_client
->dev
, "hardware revision %X\n", ret
& 0xF);
631 /* Allocate enough space for the snd_soc_codec structure
632 and our private data together. */
633 cs4270
= kzalloc(sizeof(struct cs4270_private
), GFP_KERNEL
);
635 dev_err(&i2c_client
->dev
, "could not allocate codec\n");
638 codec
= &cs4270
->codec
;
640 mutex_init(&codec
->mutex
);
641 INIT_LIST_HEAD(&codec
->dapm_widgets
);
642 INIT_LIST_HEAD(&codec
->dapm_paths
);
644 codec
->dev
= &i2c_client
->dev
;
645 codec
->name
= "CS4270";
646 codec
->owner
= THIS_MODULE
;
647 codec
->dai
= &cs4270_dai
;
649 codec
->private_data
= cs4270
;
650 codec
->control_data
= i2c_client
;
651 codec
->read
= cs4270_read_reg_cache
;
652 codec
->write
= cs4270_i2c_write
;
653 codec
->reg_cache
= cs4270
->reg_cache
;
654 codec
->reg_cache_size
= CS4270_NUMREGS
;
656 /* The I2C interface is set up, so pre-fill our register cache */
658 ret
= cs4270_fill_cache(codec
);
660 dev_err(&i2c_client
->dev
, "failed to fill register cache\n");
661 goto error_free_codec
;
664 /* Disable auto-mute. This feature appears to be buggy. In some
665 * situations, auto-mute will not deactivate when it should, so we want
666 * this feature disabled by default. An application (e.g. alsactl) can
667 * re-enabled it by using the controls.
670 reg
= cs4270_read_reg_cache(codec
, CS4270_MUTE
);
671 reg
&= ~CS4270_MUTE_AUTO
;
672 ret
= cs4270_i2c_write(codec
, CS4270_MUTE
, reg
);
674 dev_err(&i2c_client
->dev
, "i2c write failed\n");
678 /* Disable automatic volume control. The hardware enables, and it
679 * causes volume change commands to be delayed, sometimes until after
680 * playback has started. An application (e.g. alsactl) can
681 * re-enabled it by using the controls.
684 reg
= cs4270_read_reg_cache(codec
, CS4270_TRANS
);
685 reg
&= ~(CS4270_TRANS_SOFT
| CS4270_TRANS_ZERO
);
686 ret
= cs4270_i2c_write(codec
, CS4270_TRANS
, reg
);
688 dev_err(&i2c_client
->dev
, "i2c write failed\n");
692 /* Initialize the DAI. Normally, we'd prefer to have a kmalloc'd DAI
693 * structure for each CS4270 device, but the machine driver needs to
694 * have a pointer to the DAI structure, so for now it must be a global
697 cs4270_dai
.dev
= &i2c_client
->dev
;
699 /* Register the DAI. If all the other ASoC driver have already
700 * registered, then this will call our probe function, so
701 * cs4270_codec needs to be ready.
703 cs4270_codec
= codec
;
704 ret
= snd_soc_register_dai(&cs4270_dai
);
706 dev_err(&i2c_client
->dev
, "failed to register DAIe\n");
707 goto error_free_codec
;
710 i2c_set_clientdata(i2c_client
, cs4270
);
717 cs4270_dai
.dev
= NULL
;
723 * cs4270_i2c_remove - remove an I2C device
724 * @i2c_client: the I2C client object
726 * This function is the counterpart to cs4270_i2c_probe().
728 static int cs4270_i2c_remove(struct i2c_client
*i2c_client
)
730 struct cs4270_private
*cs4270
= i2c_get_clientdata(i2c_client
);
734 cs4270_dai
.dev
= NULL
;
740 * cs4270_id - I2C device IDs supported by this driver
742 static struct i2c_device_id cs4270_id
[] = {
746 MODULE_DEVICE_TABLE(i2c
, cs4270_id
);
749 * cs4270_i2c_driver - I2C device identification
751 * This structure tells the I2C subsystem how to identify and support a
752 * given I2C device type.
754 static struct i2c_driver cs4270_i2c_driver
= {
757 .owner
= THIS_MODULE
,
759 .id_table
= cs4270_id
,
760 .probe
= cs4270_i2c_probe
,
761 .remove
= cs4270_i2c_remove
,
765 * ASoC codec device structure
767 * Assign this variable to the codec_dev field of the machine driver's
768 * snd_soc_device structure.
770 struct snd_soc_codec_device soc_codec_device_cs4270
= {
771 .probe
= cs4270_probe
,
772 .remove
= cs4270_remove
774 EXPORT_SYMBOL_GPL(soc_codec_device_cs4270
);
776 static int __init
cs4270_init(void)
778 pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
780 return i2c_add_driver(&cs4270_i2c_driver
);
782 module_init(cs4270_init
);
784 static void __exit
cs4270_exit(void)
786 i2c_del_driver(&cs4270_i2c_driver
);
788 module_exit(cs4270_exit
);
790 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
791 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
792 MODULE_LICENSE("GPL");