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)
59 #define CS4270_I2C_INCR 0x80
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) */
112 unsigned int slave_mode;
113 unsigned int manual_mute;
117 * struct cs4270_mode_ratios - clock ratio tables
118 * @ratio: the ratio of MCLK to the sample rate
119 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
121 * @mclk: the Ratio Select bits to set in the Mode Control register for this
124 * The data for this chart is taken from Table 5 of the CS4270 reference
127 * This table is used to determine how to program the Mode Control register.
128 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
129 * rates the CS4270 currently supports.
131 * @speed_mode is the corresponding bit pattern to be written to the
132 * MODE bits of the Mode Control Register
134 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
135 * the Mode Control Register.
137 * In situations where a single ratio is represented by multiple speed
138 * modes, we favor the slowest speed. E.g, for a ratio of 128, we pick
139 * double-speed instead of quad-speed. However, the CS4270 errata states
140 * that divide-By-1.5 can cause failures, so we avoid that mode where
143 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
144 * work if Vd is 3.3V. If this effects you, select the
145 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
146 * never select any sample rates that require divide-by-1.5.
148 struct cs4270_mode_ratios {
154 static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
155 {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
156 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
157 {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
159 {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
160 {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
161 {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
162 {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
163 {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
164 {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
165 {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
168 /* The number of MCLK/LRCK ratios supported by the CS4270 */
169 #define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
172 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
173 * @codec_dai: the codec DAI
174 * @clk_id: the clock ID (ignored)
175 * @freq: the MCLK input frequency
176 * @dir: the clock direction (ignored)
178 * This function is used to tell the codec driver what the input MCLK
181 * The value of MCLK is used to determine which sample rates are supported
182 * by the CS4270. The ratio of MCLK / Fs must be equal to one of nine
183 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
185 * This function calculates the nine ratios and determines which ones match
186 * a standard sample rate. If there's a match, then it is added to the list
187 * of supported sample rates.
189 * This function must be called by the machine driver's 'startup' function,
190 * otherwise the list of supported sample rates will not be available in
193 static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
194 int clk_id, unsigned int freq, int dir)
196 struct snd_soc_codec *codec = codec_dai->codec;
197 struct cs4270_private *cs4270 = codec->private_data;
198 unsigned int rates = 0;
199 unsigned int rate_min = -1;
200 unsigned int rate_max = 0;
205 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
206 unsigned int rate = freq / cs4270_mode_ratios[i].ratio;
207 rates |= snd_pcm_rate_to_rate_bit(rate);
213 /* FIXME: soc should support a rate list */
214 rates &= ~SNDRV_PCM_RATE_KNOT;
217 dev_err(codec->dev, "could not find a valid sample rate\n");
221 codec_dai->playback.rates = rates;
222 codec_dai->playback.rate_min = rate_min;
223 codec_dai->playback.rate_max = rate_max;
225 codec_dai->capture.rates = rates;
226 codec_dai->capture.rate_min = rate_min;
227 codec_dai->capture.rate_max = rate_max;
233 * cs4270_set_dai_fmt - configure the codec for the selected audio format
234 * @codec_dai: the codec DAI
235 * @format: a SND_SOC_DAIFMT_x value indicating the data format
237 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
240 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
241 * SND_SOC_DAIFMT_LEFT_J. The CS4270 codec also supports right-justified
242 * data for playback only, but ASoC currently does not support different
243 * formats for playback vs. record.
245 static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
248 struct snd_soc_codec *codec = codec_dai->codec;
249 struct cs4270_private *cs4270 = codec->private_data;
253 switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
254 case SND_SOC_DAIFMT_I2S:
255 case SND_SOC_DAIFMT_LEFT_J:
256 cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
259 dev_err(codec->dev, "invalid dai format\n");
263 /* set master/slave audio interface */
264 switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
265 case SND_SOC_DAIFMT_CBS_CFS:
266 cs4270->slave_mode = 1;
268 case SND_SOC_DAIFMT_CBM_CFM:
269 cs4270->slave_mode = 0;
272 /* all other modes are unsupported by the hardware */
280 * cs4270_fill_cache - pre-fill the CS4270 register cache.
281 * @codec: the codec for this CS4270
283 * This function fills in the CS4270 register cache by reading the register
284 * values from the hardware.
286 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
287 * After the initial read to pre-fill the cache, the CS4270 never updates
288 * the register values, so we won't have a cache coherency problem.
290 * We use the auto-increment feature of the CS4270 to read all registers in
293 static int cs4270_fill_cache(struct snd_soc_codec *codec)
295 u8 *cache = codec->reg_cache;
296 struct i2c_client *i2c_client = codec->control_data;
299 length = i2c_smbus_read_i2c_block_data(i2c_client,
300 CS4270_FIRSTREG | CS4270_I2C_INCR, CS4270_NUMREGS, cache);
302 if (length != CS4270_NUMREGS) {
303 dev_err(codec->dev, "i2c read failure, addr=0x%x\n",
312 * cs4270_read_reg_cache - read from the CS4270 register cache.
313 * @codec: the codec for this CS4270
314 * @reg: the register to read
316 * This function returns the value for a given register. It reads only from
317 * the register cache, not the hardware itself.
319 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
320 * After the initial read to pre-fill the cache, the CS4270 never updates
321 * the register values, so we won't have a cache coherency problem.
323 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec *codec,
326 u8 *cache = codec->reg_cache;
328 if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
331 return cache[reg - CS4270_FIRSTREG];
335 * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
336 * @codec: the codec for this CS4270
337 * @reg: the register to write
338 * @value: the value to write to the register
340 * This function writes the given value to the given CS4270 register, and
341 * also updates the register cache.
343 * Note that we don't use the hw_write function pointer of snd_soc_codec.
344 * That's because it's too clunky: the hw_write_t prototype does not match
345 * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
347 static int cs4270_i2c_write(struct snd_soc_codec *codec, unsigned int reg,
350 u8 *cache = codec->reg_cache;
352 if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
355 /* Only perform an I2C operation if the new value is different */
356 if (cache[reg - CS4270_FIRSTREG] != value) {
357 struct i2c_client *client = codec->control_data;
358 if (i2c_smbus_write_byte_data(client, reg, value)) {
359 dev_err(codec->dev, "i2c write failed\n");
363 /* We've written to the hardware, so update the cache */
364 cache[reg - CS4270_FIRSTREG] = value;
371 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
372 * @substream: the audio stream
373 * @params: the hardware parameters to set
374 * @dai: the SOC DAI (ignored)
376 * This function programs the hardware with the values provided.
377 * Specifically, the sample rate and the data format.
379 * The .ops functions are used to provide board-specific data, like input
380 * frequencies, to this driver. This function takes that information,
381 * combines it with the hardware parameters provided, and programs the
382 * hardware accordingly.
384 static int cs4270_hw_params(struct snd_pcm_substream *substream,
385 struct snd_pcm_hw_params *params,
386 struct snd_soc_dai *dai)
388 struct snd_soc_pcm_runtime *rtd = substream->private_data;
389 struct snd_soc_device *socdev = rtd->socdev;
390 struct snd_soc_codec *codec = socdev->card->codec;
391 struct cs4270_private *cs4270 = codec->private_data;
398 /* Figure out which MCLK/LRCK ratio to use */
400 rate = params_rate(params); /* Sampling rate, in Hz */
401 ratio = cs4270->mclk / rate; /* MCLK/LRCK ratio */
403 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
404 if (cs4270_mode_ratios[i].ratio == ratio)
408 if (i == NUM_MCLK_RATIOS) {
409 /* We did not find a matching ratio */
410 dev_err(codec->dev, "could not find matching ratio\n");
414 /* Set the sample rate */
416 reg = snd_soc_read(codec, CS4270_MODE);
417 reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
418 reg |= cs4270_mode_ratios[i].mclk;
420 if (cs4270->slave_mode)
421 reg |= CS4270_MODE_SLAVE;
423 reg |= cs4270_mode_ratios[i].speed_mode;
425 ret = snd_soc_write(codec, CS4270_MODE, reg);
427 dev_err(codec->dev, "i2c write failed\n");
431 /* Set the DAI format */
433 reg = snd_soc_read(codec, CS4270_FORMAT);
434 reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
436 switch (cs4270->mode) {
437 case SND_SOC_DAIFMT_I2S:
438 reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
440 case SND_SOC_DAIFMT_LEFT_J:
441 reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
444 dev_err(codec->dev, "unknown dai format\n");
448 ret = snd_soc_write(codec, CS4270_FORMAT, reg);
450 dev_err(codec->dev, "i2c write failed\n");
458 * cs4270_dai_mute - enable/disable the CS4270 external mute
460 * @mute: 0 = disable mute, 1 = enable mute
462 * This function toggles the mute bits in the MUTE register. The CS4270's
463 * mute capability is intended for external muting circuitry, so if the
464 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
465 * then this function will do nothing.
467 static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
469 struct snd_soc_codec *codec = dai->codec;
470 struct cs4270_private *cs4270 = codec->private_data;
473 reg6 = snd_soc_read(codec, CS4270_MUTE);
476 reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
478 reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
479 reg6 |= cs4270->manual_mute;
482 return snd_soc_write(codec, CS4270_MUTE, reg6);
486 * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
488 * @kcontrol: mixer control
489 * @ucontrol: control element information
491 * This function basically passes the arguments on to the generic
492 * snd_soc_put_volsw() function and saves the mute information in
493 * our private data structure. This is because we want to prevent
494 * cs4270_dai_mute() neglecting the user's decision to manually
495 * mute the codec's output.
497 * Returns 0 for success.
499 static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
500 struct snd_ctl_elem_value *ucontrol)
502 struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
503 struct cs4270_private *cs4270 = codec->private_data;
504 int left = !ucontrol->value.integer.value[0];
505 int right = !ucontrol->value.integer.value[1];
507 cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
508 (right ? CS4270_MUTE_DAC_B : 0);
510 return snd_soc_put_volsw(kcontrol, ucontrol);
513 /* A list of non-DAPM controls that the CS4270 supports */
514 static const struct snd_kcontrol_new cs4270_snd_controls[] = {
515 SOC_DOUBLE_R("Master Playback Volume",
516 CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
517 SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
518 SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
519 SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
520 SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
521 SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
522 SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
523 SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
524 snd_soc_get_volsw, cs4270_soc_put_mute),
528 * cs4270_codec - global variable to store codec for the ASoC probe function
530 * If struct i2c_driver had a private_data field, we wouldn't need to use
531 * cs4270_codec. This is the only way to pass the codec structure from
532 * cs4270_i2c_probe() to cs4270_probe(). Unfortunately, there is no good
533 * way to synchronize these two functions. cs4270_i2c_probe() can be called
534 * multiple times before cs4270_probe() is called even once. So for now, we
535 * also only allow cs4270_i2c_probe() to be run once. That means that we do
536 * not support more than one cs4270 device in the system, at least for now.
538 static struct snd_soc_codec *cs4270_codec;
540 static struct snd_soc_dai_ops cs4270_dai_ops = {
541 .hw_params = cs4270_hw_params,
542 .set_sysclk = cs4270_set_dai_sysclk,
543 .set_fmt = cs4270_set_dai_fmt,
544 .digital_mute = cs4270_dai_mute,
547 struct snd_soc_dai cs4270_dai = {
550 .stream_name = "Playback",
554 .formats = CS4270_FORMATS,
557 .stream_name = "Capture",
561 .formats = CS4270_FORMATS,
563 .ops = &cs4270_dai_ops,
565 EXPORT_SYMBOL_GPL(cs4270_dai);
568 * cs4270_probe - ASoC probe function
569 * @pdev: platform device
571 * This function is called when ASoC has all the pieces it needs to
572 * instantiate a sound driver.
574 static int cs4270_probe(struct platform_device *pdev)
576 struct snd_soc_device *socdev = platform_get_drvdata(pdev);
577 struct snd_soc_codec *codec = cs4270_codec;
580 /* Connect the codec to the socdev. snd_soc_new_pcms() needs this. */
581 socdev->card->codec = codec;
584 ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
586 dev_err(codec->dev, "failed to create pcms\n");
590 /* Add the non-DAPM controls */
591 ret = snd_soc_add_controls(codec, cs4270_snd_controls,
592 ARRAY_SIZE(cs4270_snd_controls));
594 dev_err(codec->dev, "failed to add controls\n");
595 goto error_free_pcms;
598 /* And finally, register the socdev */
599 ret = snd_soc_init_card(socdev);
601 dev_err(codec->dev, "failed to register card\n");
602 goto error_free_pcms;
608 snd_soc_free_pcms(socdev);
614 * cs4270_remove - ASoC remove function
615 * @pdev: platform device
617 * This function is the counterpart to cs4270_probe().
619 static int cs4270_remove(struct platform_device *pdev)
621 struct snd_soc_device *socdev = platform_get_drvdata(pdev);
623 snd_soc_free_pcms(socdev);
629 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
630 * @i2c_client: the I2C client object
631 * @id: the I2C device ID (ignored)
633 * This function is called whenever the I2C subsystem finds a device that
634 * matches the device ID given via a prior call to i2c_add_driver().
636 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
637 const struct i2c_device_id *id)
639 struct snd_soc_codec *codec;
640 struct cs4270_private *cs4270;
644 /* For now, we only support one cs4270 device in the system. See the
645 * comment for cs4270_codec.
648 dev_err(&i2c_client->dev, "ignoring CS4270 at addr %X\n",
650 dev_err(&i2c_client->dev, "only one per board allowed\n");
651 /* Should we return something other than ENODEV here? */
655 /* Verify that we have a CS4270 */
657 ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);
659 dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
663 /* The top four bits of the chip ID should be 1100. */
664 if ((ret & 0xF0) != 0xC0) {
665 dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
670 dev_info(&i2c_client->dev, "found device at i2c address %X\n",
672 dev_info(&i2c_client->dev, "hardware revision %X\n", ret & 0xF);
674 /* Allocate enough space for the snd_soc_codec structure
675 and our private data together. */
676 cs4270 = kzalloc(sizeof(struct cs4270_private), GFP_KERNEL);
678 dev_err(&i2c_client->dev, "could not allocate codec\n");
681 codec = &cs4270->codec;
683 mutex_init(&codec->mutex);
684 INIT_LIST_HEAD(&codec->dapm_widgets);
685 INIT_LIST_HEAD(&codec->dapm_paths);
687 codec->dev = &i2c_client->dev;
688 codec->name = "CS4270";
689 codec->owner = THIS_MODULE;
690 codec->dai = &cs4270_dai;
692 codec->private_data = cs4270;
693 codec->control_data = i2c_client;
694 codec->read = cs4270_read_reg_cache;
695 codec->write = cs4270_i2c_write;
696 codec->reg_cache = cs4270->reg_cache;
697 codec->reg_cache_size = CS4270_NUMREGS;
699 /* The I2C interface is set up, so pre-fill our register cache */
701 ret = cs4270_fill_cache(codec);
703 dev_err(&i2c_client->dev, "failed to fill register cache\n");
704 goto error_free_codec;
707 /* Disable auto-mute. This feature appears to be buggy. In some
708 * situations, auto-mute will not deactivate when it should, so we want
709 * this feature disabled by default. An application (e.g. alsactl) can
710 * re-enabled it by using the controls.
713 reg = cs4270_read_reg_cache(codec, CS4270_MUTE);
714 reg &= ~CS4270_MUTE_AUTO;
715 ret = cs4270_i2c_write(codec, CS4270_MUTE, reg);
717 dev_err(&i2c_client->dev, "i2c write failed\n");
721 /* Disable automatic volume control. The hardware enables, and it
722 * causes volume change commands to be delayed, sometimes until after
723 * playback has started. An application (e.g. alsactl) can
724 * re-enabled it by using the controls.
727 reg = cs4270_read_reg_cache(codec, CS4270_TRANS);
728 reg &= ~(CS4270_TRANS_SOFT | CS4270_TRANS_ZERO);
729 ret = cs4270_i2c_write(codec, CS4270_TRANS, reg);
731 dev_err(&i2c_client->dev, "i2c write failed\n");
735 /* Initialize the DAI. Normally, we'd prefer to have a kmalloc'd DAI
736 * structure for each CS4270 device, but the machine driver needs to
737 * have a pointer to the DAI structure, so for now it must be a global
740 cs4270_dai.dev = &i2c_client->dev;
742 /* Register the DAI. If all the other ASoC driver have already
743 * registered, then this will call our probe function, so
744 * cs4270_codec needs to be ready.
746 cs4270_codec = codec;
747 ret = snd_soc_register_dai(&cs4270_dai);
749 dev_err(&i2c_client->dev, "failed to register DAIe\n");
750 goto error_free_codec;
753 i2c_set_clientdata(i2c_client, cs4270);
760 cs4270_dai.dev = NULL;
766 * cs4270_i2c_remove - remove an I2C device
767 * @i2c_client: the I2C client object
769 * This function is the counterpart to cs4270_i2c_probe().
771 static int cs4270_i2c_remove(struct i2c_client *i2c_client)
773 struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
777 cs4270_dai.dev = NULL;
783 * cs4270_id - I2C device IDs supported by this driver
785 static struct i2c_device_id cs4270_id[] = {
789 MODULE_DEVICE_TABLE(i2c, cs4270_id);
792 * cs4270_i2c_driver - I2C device identification
794 * This structure tells the I2C subsystem how to identify and support a
795 * given I2C device type.
797 static struct i2c_driver cs4270_i2c_driver = {
800 .owner = THIS_MODULE,
802 .id_table = cs4270_id,
803 .probe = cs4270_i2c_probe,
804 .remove = cs4270_i2c_remove,
808 * ASoC codec device structure
810 * Assign this variable to the codec_dev field of the machine driver's
811 * snd_soc_device structure.
813 struct snd_soc_codec_device soc_codec_device_cs4270 = {
814 .probe = cs4270_probe,
815 .remove = cs4270_remove
817 EXPORT_SYMBOL_GPL(soc_codec_device_cs4270);
819 static int __init cs4270_init(void)
821 pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
823 return i2c_add_driver(&cs4270_i2c_driver);
825 module_init(cs4270_init);
827 static void __exit cs4270_exit(void)
829 i2c_del_driver(&cs4270_i2c_driver);
831 module_exit(cs4270_exit);
833 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
834 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
835 MODULE_LICENSE("GPL");