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 supported
24 #include <linux/module.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 #include <sound/core.h>
28 #include <sound/soc.h>
29 #include <sound/initval.h>
30 #include <linux/i2c.h>
31 #include <linux/delay.h>
32 #include <linux/regulator/consumer.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)
60 #define CS4270_I2C_INCR 0x80
62 /* Bit masks for the CS4270 registers */
63 #define CS4270_CHIPID_ID 0xF0
64 #define CS4270_CHIPID_REV 0x0F
65 #define CS4270_PWRCTL_FREEZE 0x80
66 #define CS4270_PWRCTL_PDN_ADC 0x20
67 #define CS4270_PWRCTL_PDN_DAC 0x02
68 #define CS4270_PWRCTL_PDN 0x01
69 #define CS4270_PWRCTL_PDN_ALL \
70 (CS4270_PWRCTL_PDN_ADC | CS4270_PWRCTL_PDN_DAC | CS4270_PWRCTL_PDN)
71 #define CS4270_MODE_SPEED_MASK 0x30
72 #define CS4270_MODE_1X 0x00
73 #define CS4270_MODE_2X 0x10
74 #define CS4270_MODE_4X 0x20
75 #define CS4270_MODE_SLAVE 0x30
76 #define CS4270_MODE_DIV_MASK 0x0E
77 #define CS4270_MODE_DIV1 0x00
78 #define CS4270_MODE_DIV15 0x02
79 #define CS4270_MODE_DIV2 0x04
80 #define CS4270_MODE_DIV3 0x06
81 #define CS4270_MODE_DIV4 0x08
82 #define CS4270_MODE_POPGUARD 0x01
83 #define CS4270_FORMAT_FREEZE_A 0x80
84 #define CS4270_FORMAT_FREEZE_B 0x40
85 #define CS4270_FORMAT_LOOPBACK 0x20
86 #define CS4270_FORMAT_DAC_MASK 0x18
87 #define CS4270_FORMAT_DAC_LJ 0x00
88 #define CS4270_FORMAT_DAC_I2S 0x08
89 #define CS4270_FORMAT_DAC_RJ16 0x18
90 #define CS4270_FORMAT_DAC_RJ24 0x10
91 #define CS4270_FORMAT_ADC_MASK 0x01
92 #define CS4270_FORMAT_ADC_LJ 0x00
93 #define CS4270_FORMAT_ADC_I2S 0x01
94 #define CS4270_TRANS_ONE_VOL 0x80
95 #define CS4270_TRANS_SOFT 0x40
96 #define CS4270_TRANS_ZERO 0x20
97 #define CS4270_TRANS_INV_ADC_A 0x08
98 #define CS4270_TRANS_INV_ADC_B 0x10
99 #define CS4270_TRANS_INV_DAC_A 0x02
100 #define CS4270_TRANS_INV_DAC_B 0x04
101 #define CS4270_TRANS_DEEMPH 0x01
102 #define CS4270_MUTE_AUTO 0x20
103 #define CS4270_MUTE_ADC_A 0x08
104 #define CS4270_MUTE_ADC_B 0x10
105 #define CS4270_MUTE_POLARITY 0x04
106 #define CS4270_MUTE_DAC_A 0x01
107 #define CS4270_MUTE_DAC_B 0x02
109 static const char *supply_names[] = {
113 /* Private data for the CS4270 */
114 struct cs4270_private {
115 enum snd_soc_control_type control_type;
117 unsigned int mclk; /* Input frequency of the MCLK pin */
118 unsigned int mode; /* The mode (I2S or left-justified) */
119 unsigned int slave_mode;
120 unsigned int manual_mute;
122 /* power domain regulators */
123 struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
127 * struct cs4270_mode_ratios - clock ratio tables
128 * @ratio: the ratio of MCLK to the sample rate
129 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
131 * @mclk: the Ratio Select bits to set in the Mode Control register for this
134 * The data for this chart is taken from Table 5 of the CS4270 reference
137 * This table is used to determine how to program the Mode Control register.
138 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
139 * rates the CS4270 currently supports.
141 * @speed_mode is the corresponding bit pattern to be written to the
142 * MODE bits of the Mode Control Register
144 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
145 * the Mode Control Register.
147 * In situations where a single ratio is represented by multiple speed
148 * modes, we favor the slowest speed. E.g, for a ratio of 128, we pick
149 * double-speed instead of quad-speed. However, the CS4270 errata states
150 * that divide-By-1.5 can cause failures, so we avoid that mode where
153 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
154 * work if Vd is 3.3V. If this effects you, select the
155 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
156 * never select any sample rates that require divide-by-1.5.
158 struct cs4270_mode_ratios {
164 static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
165 {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
166 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
167 {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
169 {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
170 {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
171 {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
172 {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
173 {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
174 {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
175 {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
178 /* The number of MCLK/LRCK ratios supported by the CS4270 */
179 #define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
182 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
183 * @codec_dai: the codec DAI
184 * @clk_id: the clock ID (ignored)
185 * @freq: the MCLK input frequency
186 * @dir: the clock direction (ignored)
188 * This function is used to tell the codec driver what the input MCLK
191 * The value of MCLK is used to determine which sample rates are supported
192 * by the CS4270. The ratio of MCLK / Fs must be equal to one of nine
193 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
195 * This function calculates the nine ratios and determines which ones match
196 * a standard sample rate. If there's a match, then it is added to the list
197 * of supported sample rates.
199 * This function must be called by the machine driver's 'startup' function,
200 * otherwise the list of supported sample rates will not be available in
203 * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
204 * theoretically possible sample rates to be enabled. Call it again with a
205 * proper value set one the external clock is set (most probably you would do
206 * that from a machine's driver 'hw_param' hook.
208 static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
209 int clk_id, unsigned int freq, int dir)
211 struct snd_soc_codec *codec = codec_dai->codec;
212 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
219 * cs4270_set_dai_fmt - configure the codec for the selected audio format
220 * @codec_dai: the codec DAI
221 * @format: a SND_SOC_DAIFMT_x value indicating the data format
223 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
226 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
227 * SND_SOC_DAIFMT_LEFT_J. The CS4270 codec also supports right-justified
228 * data for playback only, but ASoC currently does not support different
229 * formats for playback vs. record.
231 static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
234 struct snd_soc_codec *codec = codec_dai->codec;
235 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
239 switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
240 case SND_SOC_DAIFMT_I2S:
241 case SND_SOC_DAIFMT_LEFT_J:
242 cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
245 dev_err(codec->dev, "invalid dai format\n");
249 /* set master/slave audio interface */
250 switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
251 case SND_SOC_DAIFMT_CBS_CFS:
252 cs4270->slave_mode = 1;
254 case SND_SOC_DAIFMT_CBM_CFM:
255 cs4270->slave_mode = 0;
258 /* all other modes are unsupported by the hardware */
266 * cs4270_fill_cache - pre-fill the CS4270 register cache.
267 * @codec: the codec for this CS4270
269 * This function fills in the CS4270 register cache by reading the register
270 * values from the hardware.
272 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
273 * After the initial read to pre-fill the cache, the CS4270 never updates
274 * the register values, so we won't have a cache coherency problem.
276 * We use the auto-increment feature of the CS4270 to read all registers in
279 static int cs4270_fill_cache(struct snd_soc_codec *codec)
281 u8 *cache = codec->reg_cache;
282 struct i2c_client *i2c_client = codec->control_data;
285 length = i2c_smbus_read_i2c_block_data(i2c_client,
286 CS4270_FIRSTREG | CS4270_I2C_INCR, CS4270_NUMREGS, cache);
288 if (length != CS4270_NUMREGS) {
289 dev_err(codec->dev, "i2c read failure, addr=0x%x\n",
298 * cs4270_read_reg_cache - read from the CS4270 register cache.
299 * @codec: the codec for this CS4270
300 * @reg: the register to read
302 * This function returns the value for a given register. It reads only from
303 * the register cache, not the hardware itself.
305 * This CS4270 registers are cached to avoid excessive I2C I/O operations.
306 * After the initial read to pre-fill the cache, the CS4270 never updates
307 * the register values, so we won't have a cache coherency problem.
309 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec *codec,
312 u8 *cache = codec->reg_cache;
314 if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
317 return cache[reg - CS4270_FIRSTREG];
321 * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
322 * @codec: the codec for this CS4270
323 * @reg: the register to write
324 * @value: the value to write to the register
326 * This function writes the given value to the given CS4270 register, and
327 * also updates the register cache.
329 * Note that we don't use the hw_write function pointer of snd_soc_codec.
330 * That's because it's too clunky: the hw_write_t prototype does not match
331 * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
333 static int cs4270_i2c_write(struct snd_soc_codec *codec, unsigned int reg,
336 u8 *cache = codec->reg_cache;
338 if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
341 /* Only perform an I2C operation if the new value is different */
342 if (cache[reg - CS4270_FIRSTREG] != value) {
343 struct i2c_client *client = codec->control_data;
344 if (i2c_smbus_write_byte_data(client, reg, value)) {
345 dev_err(codec->dev, "i2c write failed\n");
349 /* We've written to the hardware, so update the cache */
350 cache[reg - CS4270_FIRSTREG] = value;
357 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
358 * @substream: the audio stream
359 * @params: the hardware parameters to set
360 * @dai: the SOC DAI (ignored)
362 * This function programs the hardware with the values provided.
363 * Specifically, the sample rate and the data format.
365 * The .ops functions are used to provide board-specific data, like input
366 * frequencies, to this driver. This function takes that information,
367 * combines it with the hardware parameters provided, and programs the
368 * hardware accordingly.
370 static int cs4270_hw_params(struct snd_pcm_substream *substream,
371 struct snd_pcm_hw_params *params,
372 struct snd_soc_dai *dai)
374 struct snd_soc_pcm_runtime *rtd = substream->private_data;
375 struct snd_soc_codec *codec = rtd->codec;
376 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
383 /* Figure out which MCLK/LRCK ratio to use */
385 rate = params_rate(params); /* Sampling rate, in Hz */
386 ratio = cs4270->mclk / rate; /* MCLK/LRCK ratio */
388 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
389 if (cs4270_mode_ratios[i].ratio == ratio)
393 if (i == NUM_MCLK_RATIOS) {
394 /* We did not find a matching ratio */
395 dev_err(codec->dev, "could not find matching ratio\n");
399 /* Set the sample rate */
401 reg = snd_soc_read(codec, CS4270_MODE);
402 reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
403 reg |= cs4270_mode_ratios[i].mclk;
405 if (cs4270->slave_mode)
406 reg |= CS4270_MODE_SLAVE;
408 reg |= cs4270_mode_ratios[i].speed_mode;
410 ret = snd_soc_write(codec, CS4270_MODE, reg);
412 dev_err(codec->dev, "i2c write failed\n");
416 /* Set the DAI format */
418 reg = snd_soc_read(codec, CS4270_FORMAT);
419 reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
421 switch (cs4270->mode) {
422 case SND_SOC_DAIFMT_I2S:
423 reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
425 case SND_SOC_DAIFMT_LEFT_J:
426 reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
429 dev_err(codec->dev, "unknown dai format\n");
433 ret = snd_soc_write(codec, CS4270_FORMAT, reg);
435 dev_err(codec->dev, "i2c write failed\n");
443 * cs4270_dai_mute - enable/disable the CS4270 external mute
445 * @mute: 0 = disable mute, 1 = enable mute
447 * This function toggles the mute bits in the MUTE register. The CS4270's
448 * mute capability is intended for external muting circuitry, so if the
449 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
450 * then this function will do nothing.
452 static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
454 struct snd_soc_codec *codec = dai->codec;
455 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
458 reg6 = snd_soc_read(codec, CS4270_MUTE);
461 reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
463 reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
464 reg6 |= cs4270->manual_mute;
467 return snd_soc_write(codec, CS4270_MUTE, reg6);
471 * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
473 * @kcontrol: mixer control
474 * @ucontrol: control element information
476 * This function basically passes the arguments on to the generic
477 * snd_soc_put_volsw() function and saves the mute information in
478 * our private data structure. This is because we want to prevent
479 * cs4270_dai_mute() neglecting the user's decision to manually
480 * mute the codec's output.
482 * Returns 0 for success.
484 static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
485 struct snd_ctl_elem_value *ucontrol)
487 struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
488 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
489 int left = !ucontrol->value.integer.value[0];
490 int right = !ucontrol->value.integer.value[1];
492 cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
493 (right ? CS4270_MUTE_DAC_B : 0);
495 return snd_soc_put_volsw(kcontrol, ucontrol);
498 /* A list of non-DAPM controls that the CS4270 supports */
499 static const struct snd_kcontrol_new cs4270_snd_controls[] = {
500 SOC_DOUBLE_R("Master Playback Volume",
501 CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
502 SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
503 SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
504 SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
505 SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
506 SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
507 SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
508 SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
509 SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
510 snd_soc_get_volsw, cs4270_soc_put_mute),
513 static struct snd_soc_dai_ops cs4270_dai_ops = {
514 .hw_params = cs4270_hw_params,
515 .set_sysclk = cs4270_set_dai_sysclk,
516 .set_fmt = cs4270_set_dai_fmt,
517 .digital_mute = cs4270_dai_mute,
520 static struct snd_soc_dai_driver cs4270_dai = {
521 .name = "cs4270-hifi",
523 .stream_name = "Playback",
526 .rates = SNDRV_PCM_RATE_CONTINUOUS,
529 .formats = CS4270_FORMATS,
532 .stream_name = "Capture",
535 .rates = SNDRV_PCM_RATE_CONTINUOUS,
538 .formats = CS4270_FORMATS,
540 .ops = &cs4270_dai_ops,
544 * cs4270_probe - ASoC probe function
545 * @pdev: platform device
547 * This function is called when ASoC has all the pieces it needs to
548 * instantiate a sound driver.
550 static int cs4270_probe(struct snd_soc_codec *codec)
552 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
555 codec->control_data = cs4270->control_data;
557 /* The I2C interface is set up, so pre-fill our register cache */
559 ret = cs4270_fill_cache(codec);
561 dev_err(codec->dev, "failed to fill register cache\n");
565 /* Disable auto-mute. This feature appears to be buggy. In some
566 * situations, auto-mute will not deactivate when it should, so we want
567 * this feature disabled by default. An application (e.g. alsactl) can
568 * re-enabled it by using the controls.
571 reg = cs4270_read_reg_cache(codec, CS4270_MUTE);
572 reg &= ~CS4270_MUTE_AUTO;
573 ret = cs4270_i2c_write(codec, CS4270_MUTE, reg);
575 dev_err(codec->dev, "i2c write failed\n");
579 /* Disable automatic volume control. The hardware enables, and it
580 * causes volume change commands to be delayed, sometimes until after
581 * playback has started. An application (e.g. alsactl) can
582 * re-enabled it by using the controls.
585 reg = cs4270_read_reg_cache(codec, CS4270_TRANS);
586 reg &= ~(CS4270_TRANS_SOFT | CS4270_TRANS_ZERO);
587 ret = cs4270_i2c_write(codec, CS4270_TRANS, reg);
589 dev_err(codec->dev, "i2c write failed\n");
593 /* Add the non-DAPM controls */
594 ret = snd_soc_add_controls(codec, cs4270_snd_controls,
595 ARRAY_SIZE(cs4270_snd_controls));
597 dev_err(codec->dev, "failed to add controls\n");
601 /* get the power supply regulators */
602 for (i = 0; i < ARRAY_SIZE(supply_names); i++)
603 cs4270->supplies[i].supply = supply_names[i];
605 ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(cs4270->supplies),
610 ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
613 goto error_free_regulators;
617 error_free_regulators:
618 regulator_bulk_free(ARRAY_SIZE(cs4270->supplies),
625 * cs4270_remove - ASoC remove function
626 * @pdev: platform device
628 * This function is the counterpart to cs4270_probe().
630 static int cs4270_remove(struct snd_soc_codec *codec)
632 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
634 regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
635 regulator_bulk_free(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
642 /* This suspend/resume implementation can handle both - a simple standby
643 * where the codec remains powered, and a full suspend, where the voltage
644 * domain the codec is connected to is teared down and/or any other hardware
645 * reset condition is asserted.
647 * The codec's own power saving features are enabled in the suspend callback,
648 * and all registers are written back to the hardware when resuming.
651 static int cs4270_soc_suspend(struct snd_soc_codec *codec, pm_message_t mesg)
653 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
656 reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
660 ret = snd_soc_write(codec, CS4270_PWRCTL, reg);
664 regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
670 static int cs4270_soc_resume(struct snd_soc_codec *codec)
672 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
673 struct i2c_client *i2c_client = codec->control_data;
676 regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
679 /* In case the device was put to hard reset during sleep, we need to
680 * wait 500ns here before any I2C communication. */
683 /* first restore the entire register cache ... */
684 for (reg = CS4270_FIRSTREG; reg <= CS4270_LASTREG; reg++) {
685 u8 val = snd_soc_read(codec, reg);
687 if (i2c_smbus_write_byte_data(i2c_client, reg, val)) {
688 dev_err(codec->dev, "i2c write failed\n");
693 /* ... then disable the power-down bits */
694 reg = snd_soc_read(codec, CS4270_PWRCTL);
695 reg &= ~CS4270_PWRCTL_PDN_ALL;
697 return snd_soc_write(codec, CS4270_PWRCTL, reg);
700 #define cs4270_soc_suspend NULL
701 #define cs4270_soc_resume NULL
702 #endif /* CONFIG_PM */
705 * ASoC codec device structure
707 * Assign this variable to the codec_dev field of the machine driver's
708 * snd_soc_device structure.
710 static struct snd_soc_codec_driver soc_codec_device_cs4270 = {
711 .probe = cs4270_probe,
712 .remove = cs4270_remove,
713 .suspend = cs4270_soc_suspend,
714 .resume = cs4270_soc_resume,
715 .read = cs4270_read_reg_cache,
716 .write = cs4270_i2c_write,
717 .reg_cache_size = CS4270_NUMREGS,
718 .reg_word_size = sizeof(u8),
722 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
723 * @i2c_client: the I2C client object
724 * @id: the I2C device ID (ignored)
726 * This function is called whenever the I2C subsystem finds a device that
727 * matches the device ID given via a prior call to i2c_add_driver().
729 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
730 const struct i2c_device_id *id)
732 struct cs4270_private *cs4270;
735 /* Verify that we have a CS4270 */
737 ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);
739 dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
743 /* The top four bits of the chip ID should be 1100. */
744 if ((ret & 0xF0) != 0xC0) {
745 dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
750 dev_info(&i2c_client->dev, "found device at i2c address %X\n",
752 dev_info(&i2c_client->dev, "hardware revision %X\n", ret & 0xF);
754 cs4270 = kzalloc(sizeof(struct cs4270_private), GFP_KERNEL);
756 dev_err(&i2c_client->dev, "could not allocate codec\n");
760 i2c_set_clientdata(i2c_client, cs4270);
761 cs4270->control_data = i2c_client;
762 cs4270->control_type = SND_SOC_I2C;
764 ret = snd_soc_register_codec(&i2c_client->dev,
765 &soc_codec_device_cs4270, &cs4270_dai, 1);
772 * cs4270_i2c_remove - remove an I2C device
773 * @i2c_client: the I2C client object
775 * This function is the counterpart to cs4270_i2c_probe().
777 static int cs4270_i2c_remove(struct i2c_client *i2c_client)
779 snd_soc_unregister_codec(&i2c_client->dev);
780 kfree(i2c_get_clientdata(i2c_client));
785 * cs4270_id - I2C device IDs supported by this driver
787 static struct i2c_device_id cs4270_id[] = {
791 MODULE_DEVICE_TABLE(i2c, cs4270_id);
794 * cs4270_i2c_driver - I2C device identification
796 * This structure tells the I2C subsystem how to identify and support a
797 * given I2C device type.
799 static struct i2c_driver cs4270_i2c_driver = {
801 .name = "cs4270-codec",
802 .owner = THIS_MODULE,
804 .id_table = cs4270_id,
805 .probe = cs4270_i2c_probe,
806 .remove = cs4270_i2c_remove,
809 static int __init cs4270_init(void)
811 pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
813 return i2c_add_driver(&cs4270_i2c_driver);
815 module_init(cs4270_init);
817 static void __exit cs4270_exit(void)
819 i2c_del_driver(&cs4270_i2c_driver);
821 module_exit(cs4270_exit);
823 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
824 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
825 MODULE_LICENSE("GPL");