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 * - Software mode is supported. Stand-alone mode is not supported.
16 * - Only I2C is supported, not SPI
17 * - Support for master and slave mode
18 * - The machine driver's 'startup' function must call
19 * cs4270_set_dai_sysclk() with the value of MCLK.
20 * - Only I2S and left-justified modes are supported
21 * - Power management is not supported
24 #include <linux/module.h>
25 #include <linux/platform_device.h>
26 #include <sound/core.h>
27 #include <sound/soc.h>
28 #include <sound/initval.h>
29 #include <linux/i2c.h>
34 * The codec isn't really big-endian or little-endian, since the I2S
35 * interface requires data to be sent serially with the MSbit first.
36 * However, to support BE and LE I2S devices, we specify both here. That
37 * way, ALSA will always match the bit patterns.
39 #define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8 | \
40 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE | \
41 SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S18_3BE | \
42 SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S20_3BE | \
43 SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | \
44 SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE)
46 /* CS4270 registers addresses */
47 #define CS4270_CHIPID 0x01 /* Chip ID */
48 #define CS4270_PWRCTL 0x02 /* Power Control */
49 #define CS4270_MODE 0x03 /* Mode Control */
50 #define CS4270_FORMAT 0x04 /* Serial Format, ADC/DAC Control */
51 #define CS4270_TRANS 0x05 /* Transition Control */
52 #define CS4270_MUTE 0x06 /* Mute Control */
53 #define CS4270_VOLA 0x07 /* DAC Channel A Volume Control */
54 #define CS4270_VOLB 0x08 /* DAC Channel B Volume Control */
56 #define CS4270_FIRSTREG 0x01
57 #define CS4270_LASTREG 0x08
58 #define CS4270_NUMREGS (CS4270_LASTREG - CS4270_FIRSTREG + 1)
60 /* Bit masks for the CS4270 registers */
61 #define CS4270_CHIPID_ID 0xF0
62 #define CS4270_CHIPID_REV 0x0F
63 #define CS4270_PWRCTL_FREEZE 0x80
64 #define CS4270_PWRCTL_PDN_ADC 0x20
65 #define CS4270_PWRCTL_PDN_DAC 0x02
66 #define CS4270_PWRCTL_PDN 0x01
67 #define CS4270_MODE_SPEED_MASK 0x30
68 #define CS4270_MODE_1X 0x00
69 #define CS4270_MODE_2X 0x10
70 #define CS4270_MODE_4X 0x20
71 #define CS4270_MODE_SLAVE 0x30
72 #define CS4270_MODE_DIV_MASK 0x0E
73 #define CS4270_MODE_DIV1 0x00
74 #define CS4270_MODE_DIV15 0x02
75 #define CS4270_MODE_DIV2 0x04
76 #define CS4270_MODE_DIV3 0x06
77 #define CS4270_MODE_DIV4 0x08
78 #define CS4270_MODE_POPGUARD 0x01
79 #define CS4270_FORMAT_FREEZE_A 0x80
80 #define CS4270_FORMAT_FREEZE_B 0x40
81 #define CS4270_FORMAT_LOOPBACK 0x20
82 #define CS4270_FORMAT_DAC_MASK 0x18
83 #define CS4270_FORMAT_DAC_LJ 0x00
84 #define CS4270_FORMAT_DAC_I2S 0x08
85 #define CS4270_FORMAT_DAC_RJ16 0x18
86 #define CS4270_FORMAT_DAC_RJ24 0x10
87 #define CS4270_FORMAT_ADC_MASK 0x01
88 #define CS4270_FORMAT_ADC_LJ 0x00
89 #define CS4270_FORMAT_ADC_I2S 0x01
90 #define CS4270_TRANS_ONE_VOL 0x80
91 #define CS4270_TRANS_SOFT 0x40
92 #define CS4270_TRANS_ZERO 0x20
93 #define CS4270_TRANS_INV_ADC_A 0x08
94 #define CS4270_TRANS_INV_ADC_B 0x10
95 #define CS4270_TRANS_INV_DAC_A 0x02
96 #define CS4270_TRANS_INV_DAC_B 0x04
97 #define CS4270_TRANS_DEEMPH 0x01
98 #define CS4270_MUTE_AUTO 0x20
99 #define CS4270_MUTE_ADC_A 0x08
100 #define CS4270_MUTE_ADC_B 0x10
101 #define CS4270_MUTE_POLARITY 0x04
102 #define CS4270_MUTE_DAC_A 0x01
103 #define CS4270_MUTE_DAC_B 0x02
105 /* Private data for the CS4270 */
106 struct cs4270_private
{
107 struct snd_soc_codec codec
;
108 u8 reg_cache
[CS4270_NUMREGS
];
109 unsigned int mclk
; /* Input frequency of the MCLK pin */
110 unsigned int mode
; /* The mode (I2S or left-justified) */
111 unsigned int slave_mode
;
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
;
251 switch (format
& SND_SOC_DAIFMT_FORMAT_MASK
) {
252 case SND_SOC_DAIFMT_I2S
:
253 case SND_SOC_DAIFMT_LEFT_J
:
254 cs4270
->mode
= format
& SND_SOC_DAIFMT_FORMAT_MASK
;
257 dev_err(codec
->dev
, "invalid dai format\n");
261 /* set master/slave audio interface */
262 switch (format
& SND_SOC_DAIFMT_MASTER_MASK
) {
263 case SND_SOC_DAIFMT_CBS_CFS
:
264 cs4270
->slave_mode
= 1;
266 case SND_SOC_DAIFMT_CBM_CFM
:
267 cs4270
->slave_mode
= 0;
270 /* all other modes are unsupported by the hardware */
278 * cs4270_fill_cache - pre-fill the CS4270 register cache.
279 * @codec: the codec for this CS4270
281 * This function fills in the CS4270 register cache by reading the register
282 * values from the hardware.
284 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
285 * After the initial read to pre-fill the cache, the CS4270 never updates
286 * the register values, so we won't have a cache coherency problem.
288 * We use the auto-increment feature of the CS4270 to read all registers in
291 static int cs4270_fill_cache(struct snd_soc_codec
*codec
)
293 u8
*cache
= codec
->reg_cache
;
294 struct i2c_client
*i2c_client
= codec
->control_data
;
297 length
= i2c_smbus_read_i2c_block_data(i2c_client
,
298 CS4270_FIRSTREG
| 0x80, CS4270_NUMREGS
, cache
);
300 if (length
!= CS4270_NUMREGS
) {
301 dev_err(codec
->dev
, "i2c read failure, addr=0x%x\n",
310 * cs4270_read_reg_cache - read from the CS4270 register cache.
311 * @codec: the codec for this CS4270
312 * @reg: the register to read
314 * This function returns the value for a given register. It reads only from
315 * the register cache, not the hardware itself.
317 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
318 * After the initial read to pre-fill the cache, the CS4270 never updates
319 * the register values, so we won't have a cache coherency problem.
321 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec
*codec
,
324 u8
*cache
= codec
->reg_cache
;
326 if ((reg
< CS4270_FIRSTREG
) || (reg
> CS4270_LASTREG
))
329 return cache
[reg
- CS4270_FIRSTREG
];
333 * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
334 * @codec: the codec for this CS4270
335 * @reg: the register to write
336 * @value: the value to write to the register
338 * This function writes the given value to the given CS4270 register, and
339 * also updates the register cache.
341 * Note that we don't use the hw_write function pointer of snd_soc_codec.
342 * That's because it's too clunky: the hw_write_t prototype does not match
343 * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
345 static int cs4270_i2c_write(struct snd_soc_codec
*codec
, unsigned int reg
,
348 u8
*cache
= codec
->reg_cache
;
350 if ((reg
< CS4270_FIRSTREG
) || (reg
> CS4270_LASTREG
))
353 /* Only perform an I2C operation if the new value is different */
354 if (cache
[reg
- CS4270_FIRSTREG
] != value
) {
355 struct i2c_client
*client
= codec
->control_data
;
356 if (i2c_smbus_write_byte_data(client
, reg
, value
)) {
357 dev_err(codec
->dev
, "i2c write failed\n");
361 /* We've written to the hardware, so update the cache */
362 cache
[reg
- CS4270_FIRSTREG
] = value
;
369 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
370 * @substream: the audio stream
371 * @params: the hardware parameters to set
372 * @dai: the SOC DAI (ignored)
374 * This function programs the hardware with the values provided.
375 * Specifically, the sample rate and the data format.
377 * The .ops functions are used to provide board-specific data, like input
378 * frequencies, to this driver. This function takes that information,
379 * combines it with the hardware parameters provided, and programs the
380 * hardware accordingly.
382 static int cs4270_hw_params(struct snd_pcm_substream
*substream
,
383 struct snd_pcm_hw_params
*params
,
384 struct snd_soc_dai
*dai
)
386 struct snd_soc_pcm_runtime
*rtd
= substream
->private_data
;
387 struct snd_soc_device
*socdev
= rtd
->socdev
;
388 struct snd_soc_codec
*codec
= socdev
->card
->codec
;
389 struct cs4270_private
*cs4270
= codec
->private_data
;
396 /* Figure out which MCLK/LRCK ratio to use */
398 rate
= params_rate(params
); /* Sampling rate, in Hz */
399 ratio
= cs4270
->mclk
/ rate
; /* MCLK/LRCK ratio */
401 for (i
= 0; i
< NUM_MCLK_RATIOS
; i
++) {
402 if (cs4270_mode_ratios
[i
].ratio
== ratio
)
406 if (i
== NUM_MCLK_RATIOS
) {
407 /* We did not find a matching ratio */
408 dev_err(codec
->dev
, "could not find matching ratio\n");
412 /* Set the sample rate */
414 reg
= snd_soc_read(codec
, CS4270_MODE
);
415 reg
&= ~(CS4270_MODE_SPEED_MASK
| CS4270_MODE_DIV_MASK
);
416 reg
|= cs4270_mode_ratios
[i
].mclk
;
418 if (cs4270
->slave_mode
)
419 reg
|= CS4270_MODE_SLAVE
;
421 reg
|= cs4270_mode_ratios
[i
].speed_mode
;
423 ret
= snd_soc_write(codec
, CS4270_MODE
, reg
);
425 dev_err(codec
->dev
, "i2c write failed\n");
429 /* Set the DAI format */
431 reg
= snd_soc_read(codec
, CS4270_FORMAT
);
432 reg
&= ~(CS4270_FORMAT_DAC_MASK
| CS4270_FORMAT_ADC_MASK
);
434 switch (cs4270
->mode
) {
435 case SND_SOC_DAIFMT_I2S
:
436 reg
|= CS4270_FORMAT_DAC_I2S
| CS4270_FORMAT_ADC_I2S
;
438 case SND_SOC_DAIFMT_LEFT_J
:
439 reg
|= CS4270_FORMAT_DAC_LJ
| CS4270_FORMAT_ADC_LJ
;
442 dev_err(codec
->dev
, "unknown dai format\n");
446 ret
= snd_soc_write(codec
, CS4270_FORMAT
, reg
);
448 dev_err(codec
->dev
, "i2c write failed\n");
456 * cs4270_mute - enable/disable the CS4270 external mute
458 * @mute: 0 = disable mute, 1 = enable mute
460 * This function toggles the mute bits in the MUTE register. The CS4270's
461 * mute capability is intended for external muting circuitry, so if the
462 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
463 * then this function will do nothing.
465 static int cs4270_mute(struct snd_soc_dai
*dai
, int mute
)
467 struct snd_soc_codec
*codec
= dai
->codec
;
470 reg6
= snd_soc_read(codec
, CS4270_MUTE
);
473 reg6
|= CS4270_MUTE_DAC_A
| CS4270_MUTE_DAC_B
;
475 reg6
&= ~(CS4270_MUTE_DAC_A
| CS4270_MUTE_DAC_B
);
477 return snd_soc_write(codec
, CS4270_MUTE
, reg6
);
480 /* A list of non-DAPM controls that the CS4270 supports */
481 static const struct snd_kcontrol_new cs4270_snd_controls
[] = {
482 SOC_DOUBLE_R("Master Playback Volume",
483 CS4270_VOLA
, CS4270_VOLB
, 0, 0xFF, 1),
484 SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT
, 5, 1, 0),
485 SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS
, 6, 1, 0),
486 SOC_SINGLE("Zero Cross Switch", CS4270_TRANS
, 5, 1, 0),
487 SOC_SINGLE("Popguard Switch", CS4270_MODE
, 0, 1, 1),
488 SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE
, 5, 1, 0),
489 SOC_DOUBLE("Master Capture Switch", CS4270_MUTE
, 3, 4, 1, 0)
493 * cs4270_codec - global variable to store codec for the ASoC probe function
495 * If struct i2c_driver had a private_data field, we wouldn't need to use
496 * cs4270_codec. This is the only way to pass the codec structure from
497 * cs4270_i2c_probe() to cs4270_probe(). Unfortunately, there is no good
498 * way to synchronize these two functions. cs4270_i2c_probe() can be called
499 * multiple times before cs4270_probe() is called even once. So for now, we
500 * also only allow cs4270_i2c_probe() to be run once. That means that we do
501 * not support more than one cs4270 device in the system, at least for now.
503 static struct snd_soc_codec
*cs4270_codec
;
505 static struct snd_soc_dai_ops cs4270_dai_ops
= {
506 .hw_params
= cs4270_hw_params
,
507 .set_sysclk
= cs4270_set_dai_sysclk
,
508 .set_fmt
= cs4270_set_dai_fmt
,
509 .digital_mute
= cs4270_mute
,
512 struct snd_soc_dai cs4270_dai
= {
515 .stream_name
= "Playback",
519 .formats
= CS4270_FORMATS
,
522 .stream_name
= "Capture",
526 .formats
= CS4270_FORMATS
,
528 .ops
= &cs4270_dai_ops
,
530 EXPORT_SYMBOL_GPL(cs4270_dai
);
533 * cs4270_probe - ASoC probe function
534 * @pdev: platform device
536 * This function is called when ASoC has all the pieces it needs to
537 * instantiate a sound driver.
539 static int cs4270_probe(struct platform_device
*pdev
)
541 struct snd_soc_device
*socdev
= platform_get_drvdata(pdev
);
542 struct snd_soc_codec
*codec
= cs4270_codec
;
545 /* Connect the codec to the socdev. snd_soc_new_pcms() needs this. */
546 socdev
->card
->codec
= codec
;
549 ret
= snd_soc_new_pcms(socdev
, SNDRV_DEFAULT_IDX1
, SNDRV_DEFAULT_STR1
);
551 dev_err(codec
->dev
, "failed to create pcms\n");
555 /* Add the non-DAPM controls */
556 ret
= snd_soc_add_controls(codec
, cs4270_snd_controls
,
557 ARRAY_SIZE(cs4270_snd_controls
));
559 dev_err(codec
->dev
, "failed to add controls\n");
560 goto error_free_pcms
;
563 /* And finally, register the socdev */
564 ret
= snd_soc_init_card(socdev
);
566 dev_err(codec
->dev
, "failed to register card\n");
567 goto error_free_pcms
;
573 snd_soc_free_pcms(socdev
);
579 * cs4270_remove - ASoC remove function
580 * @pdev: platform device
582 * This function is the counterpart to cs4270_probe().
584 static int cs4270_remove(struct platform_device
*pdev
)
586 struct snd_soc_device
*socdev
= platform_get_drvdata(pdev
);
588 snd_soc_free_pcms(socdev
);
594 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
595 * @i2c_client: the I2C client object
596 * @id: the I2C device ID (ignored)
598 * This function is called whenever the I2C subsystem finds a device that
599 * matches the device ID given via a prior call to i2c_add_driver().
601 static int cs4270_i2c_probe(struct i2c_client
*i2c_client
,
602 const struct i2c_device_id
*id
)
604 struct snd_soc_codec
*codec
;
605 struct cs4270_private
*cs4270
;
609 /* For now, we only support one cs4270 device in the system. See the
610 * comment for cs4270_codec.
613 dev_err(&i2c_client
->dev
, "ignoring CS4270 at addr %X\n",
615 dev_err(&i2c_client
->dev
, "only one per board allowed\n");
616 /* Should we return something other than ENODEV here? */
620 /* Verify that we have a CS4270 */
622 ret
= i2c_smbus_read_byte_data(i2c_client
, CS4270_CHIPID
);
624 dev_err(&i2c_client
->dev
, "failed to read i2c at addr %X\n",
628 /* The top four bits of the chip ID should be 1100. */
629 if ((ret
& 0xF0) != 0xC0) {
630 dev_err(&i2c_client
->dev
, "device at addr %X is not a CS4270\n",
635 dev_info(&i2c_client
->dev
, "found device at i2c address %X\n",
637 dev_info(&i2c_client
->dev
, "hardware revision %X\n", ret
& 0xF);
639 /* Allocate enough space for the snd_soc_codec structure
640 and our private data together. */
641 cs4270
= kzalloc(sizeof(struct cs4270_private
), GFP_KERNEL
);
643 dev_err(&i2c_client
->dev
, "could not allocate codec\n");
646 codec
= &cs4270
->codec
;
648 mutex_init(&codec
->mutex
);
649 INIT_LIST_HEAD(&codec
->dapm_widgets
);
650 INIT_LIST_HEAD(&codec
->dapm_paths
);
652 codec
->dev
= &i2c_client
->dev
;
653 codec
->name
= "CS4270";
654 codec
->owner
= THIS_MODULE
;
655 codec
->dai
= &cs4270_dai
;
657 codec
->private_data
= cs4270
;
658 codec
->control_data
= i2c_client
;
659 codec
->read
= cs4270_read_reg_cache
;
660 codec
->write
= cs4270_i2c_write
;
661 codec
->reg_cache
= cs4270
->reg_cache
;
662 codec
->reg_cache_size
= CS4270_NUMREGS
;
664 /* The I2C interface is set up, so pre-fill our register cache */
666 ret
= cs4270_fill_cache(codec
);
668 dev_err(&i2c_client
->dev
, "failed to fill register cache\n");
669 goto error_free_codec
;
672 /* Disable auto-mute. This feature appears to be buggy. In some
673 * situations, auto-mute will not deactivate when it should, so we want
674 * this feature disabled by default. An application (e.g. alsactl) can
675 * re-enabled it by using the controls.
678 reg
= cs4270_read_reg_cache(codec
, CS4270_MUTE
);
679 reg
&= ~CS4270_MUTE_AUTO
;
680 ret
= cs4270_i2c_write(codec
, CS4270_MUTE
, reg
);
682 dev_err(&i2c_client
->dev
, "i2c write failed\n");
686 /* Disable automatic volume control. The hardware enables, and it
687 * causes volume change commands to be delayed, sometimes until after
688 * playback has started. An application (e.g. alsactl) can
689 * re-enabled it by using the controls.
692 reg
= cs4270_read_reg_cache(codec
, CS4270_TRANS
);
693 reg
&= ~(CS4270_TRANS_SOFT
| CS4270_TRANS_ZERO
);
694 ret
= cs4270_i2c_write(codec
, CS4270_TRANS
, reg
);
696 dev_err(&i2c_client
->dev
, "i2c write failed\n");
700 /* Initialize the DAI. Normally, we'd prefer to have a kmalloc'd DAI
701 * structure for each CS4270 device, but the machine driver needs to
702 * have a pointer to the DAI structure, so for now it must be a global
705 cs4270_dai
.dev
= &i2c_client
->dev
;
707 /* Register the DAI. If all the other ASoC driver have already
708 * registered, then this will call our probe function, so
709 * cs4270_codec needs to be ready.
711 cs4270_codec
= codec
;
712 ret
= snd_soc_register_dai(&cs4270_dai
);
714 dev_err(&i2c_client
->dev
, "failed to register DAIe\n");
715 goto error_free_codec
;
718 i2c_set_clientdata(i2c_client
, cs4270
);
725 cs4270_dai
.dev
= NULL
;
731 * cs4270_i2c_remove - remove an I2C device
732 * @i2c_client: the I2C client object
734 * This function is the counterpart to cs4270_i2c_probe().
736 static int cs4270_i2c_remove(struct i2c_client
*i2c_client
)
738 struct cs4270_private
*cs4270
= i2c_get_clientdata(i2c_client
);
742 cs4270_dai
.dev
= NULL
;
748 * cs4270_id - I2C device IDs supported by this driver
750 static struct i2c_device_id cs4270_id
[] = {
754 MODULE_DEVICE_TABLE(i2c
, cs4270_id
);
757 * cs4270_i2c_driver - I2C device identification
759 * This structure tells the I2C subsystem how to identify and support a
760 * given I2C device type.
762 static struct i2c_driver cs4270_i2c_driver
= {
765 .owner
= THIS_MODULE
,
767 .id_table
= cs4270_id
,
768 .probe
= cs4270_i2c_probe
,
769 .remove
= cs4270_i2c_remove
,
773 * ASoC codec device structure
775 * Assign this variable to the codec_dev field of the machine driver's
776 * snd_soc_device structure.
778 struct snd_soc_codec_device soc_codec_device_cs4270
= {
779 .probe
= cs4270_probe
,
780 .remove
= cs4270_remove
782 EXPORT_SYMBOL_GPL(soc_codec_device_cs4270
);
784 static int __init
cs4270_init(void)
786 pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
788 return i2c_add_driver(&cs4270_i2c_driver
);
790 module_init(cs4270_init
);
792 static void __exit
cs4270_exit(void)
794 i2c_del_driver(&cs4270_i2c_driver
);
796 module_exit(cs4270_exit
);
798 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
799 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
800 MODULE_LICENSE("GPL");