linux/sound/soc/codecs/cs4270.c
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   1/*
   2 * CS4270 ALSA SoC (ASoC) codec driver
   3 *
   4 * Author: Timur Tabi <timur@freescale.com>
   5 *
   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
   9 * express or implied.
  10 *
  11 * This is an ASoC device driver for the Cirrus Logic CS4270 codec.
  12 *
  13 * Current features/limitations:
  14 *
  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
  22 */
  23
  24#include <linux/module.h>
  25#include <linux/slab.h>
  26#include <sound/core.h>
  27#include <sound/soc.h>
  28#include <sound/initval.h>
  29#include <linux/i2c.h>
  30#include <linux/delay.h>
  31#include <linux/regulator/consumer.h>
  32#include <linux/of_device.h>
  33#include <linux/of_gpio.h>
  34
  35/*
  36 * The codec isn't really big-endian or little-endian, since the I2S
  37 * interface requires data to be sent serially with the MSbit first.
  38 * However, to support BE and LE I2S devices, we specify both here.  That
  39 * way, ALSA will always match the bit patterns.
  40 */
  41#define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8      | \
  42                        SNDRV_PCM_FMTBIT_S16_LE  | SNDRV_PCM_FMTBIT_S16_BE  | \
  43                        SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S18_3BE | \
  44                        SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S20_3BE | \
  45                        SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | \
  46                        SNDRV_PCM_FMTBIT_S24_LE  | SNDRV_PCM_FMTBIT_S24_BE)
  47
  48/* CS4270 registers addresses */
  49#define CS4270_CHIPID   0x01    /* Chip ID */
  50#define CS4270_PWRCTL   0x02    /* Power Control */
  51#define CS4270_MODE     0x03    /* Mode Control */
  52#define CS4270_FORMAT   0x04    /* Serial Format, ADC/DAC Control */
  53#define CS4270_TRANS    0x05    /* Transition Control */
  54#define CS4270_MUTE     0x06    /* Mute Control */
  55#define CS4270_VOLA     0x07    /* DAC Channel A Volume Control */
  56#define CS4270_VOLB     0x08    /* DAC Channel B Volume Control */
  57
  58#define CS4270_FIRSTREG 0x01
  59#define CS4270_LASTREG  0x08
  60#define CS4270_NUMREGS  (CS4270_LASTREG - CS4270_FIRSTREG + 1)
  61#define CS4270_I2C_INCR 0x80
  62
  63/* Bit masks for the CS4270 registers */
  64#define CS4270_CHIPID_ID        0xF0
  65#define CS4270_CHIPID_REV       0x0F
  66#define CS4270_PWRCTL_FREEZE    0x80
  67#define CS4270_PWRCTL_PDN_ADC   0x20
  68#define CS4270_PWRCTL_PDN_DAC   0x02
  69#define CS4270_PWRCTL_PDN       0x01
  70#define CS4270_PWRCTL_PDN_ALL   \
  71        (CS4270_PWRCTL_PDN_ADC | CS4270_PWRCTL_PDN_DAC | CS4270_PWRCTL_PDN)
  72#define CS4270_MODE_SPEED_MASK  0x30
  73#define CS4270_MODE_1X          0x00
  74#define CS4270_MODE_2X          0x10
  75#define CS4270_MODE_4X          0x20
  76#define CS4270_MODE_SLAVE       0x30
  77#define CS4270_MODE_DIV_MASK    0x0E
  78#define CS4270_MODE_DIV1        0x00
  79#define CS4270_MODE_DIV15       0x02
  80#define CS4270_MODE_DIV2        0x04
  81#define CS4270_MODE_DIV3        0x06
  82#define CS4270_MODE_DIV4        0x08
  83#define CS4270_MODE_POPGUARD    0x01
  84#define CS4270_FORMAT_FREEZE_A  0x80
  85#define CS4270_FORMAT_FREEZE_B  0x40
  86#define CS4270_FORMAT_LOOPBACK  0x20
  87#define CS4270_FORMAT_DAC_MASK  0x18
  88#define CS4270_FORMAT_DAC_LJ    0x00
  89#define CS4270_FORMAT_DAC_I2S   0x08
  90#define CS4270_FORMAT_DAC_RJ16  0x18
  91#define CS4270_FORMAT_DAC_RJ24  0x10
  92#define CS4270_FORMAT_ADC_MASK  0x01
  93#define CS4270_FORMAT_ADC_LJ    0x00
  94#define CS4270_FORMAT_ADC_I2S   0x01
  95#define CS4270_TRANS_ONE_VOL    0x80
  96#define CS4270_TRANS_SOFT       0x40
  97#define CS4270_TRANS_ZERO       0x20
  98#define CS4270_TRANS_INV_ADC_A  0x08
  99#define CS4270_TRANS_INV_ADC_B  0x10
 100#define CS4270_TRANS_INV_DAC_A  0x02
 101#define CS4270_TRANS_INV_DAC_B  0x04
 102#define CS4270_TRANS_DEEMPH     0x01
 103#define CS4270_MUTE_AUTO        0x20
 104#define CS4270_MUTE_ADC_A       0x08
 105#define CS4270_MUTE_ADC_B       0x10
 106#define CS4270_MUTE_POLARITY    0x04
 107#define CS4270_MUTE_DAC_A       0x01
 108#define CS4270_MUTE_DAC_B       0x02
 109
 110/* Power-on default values for the registers
 111 *
 112 * This array contains the power-on default values of the registers, with the
 113 * exception of the "CHIPID" register (01h).  The lower four bits of that
 114 * register contain the hardware revision, so it is treated as volatile.
 115 */
 116static const struct reg_default cs4270_reg_defaults[] = {
 117        { 2, 0x00 },
 118        { 3, 0x30 },
 119        { 4, 0x00 },
 120        { 5, 0x60 },
 121        { 6, 0x20 },
 122        { 7, 0x00 },
 123        { 8, 0x00 },
 124};
 125
 126static const char *supply_names[] = {
 127        "va", "vd", "vlc"
 128};
 129
 130/* Private data for the CS4270 */
 131struct cs4270_private {
 132        struct regmap *regmap;
 133        unsigned int mclk; /* Input frequency of the MCLK pin */
 134        unsigned int mode; /* The mode (I2S or left-justified) */
 135        unsigned int slave_mode;
 136        unsigned int manual_mute;
 137
 138        /* power domain regulators */
 139        struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
 140};
 141
 142static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
 143SND_SOC_DAPM_INPUT("AINL"),
 144SND_SOC_DAPM_INPUT("AINR"),
 145
 146SND_SOC_DAPM_OUTPUT("AOUTL"),
 147SND_SOC_DAPM_OUTPUT("AOUTR"),
 148};
 149
 150static const struct snd_soc_dapm_route cs4270_dapm_routes[] = {
 151        { "Capture", NULL, "AINA" },
 152        { "Capture", NULL, "AINB" },
 153
 154        { "AOUTA", NULL, "Playback" },
 155        { "AOUTB", NULL, "Playback" },
 156};
 157
 158/**
 159 * struct cs4270_mode_ratios - clock ratio tables
 160 * @ratio: the ratio of MCLK to the sample rate
 161 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
 162 *              this ratio
 163 * @mclk: the Ratio Select bits to set in the Mode Control register for this
 164 *        ratio
 165 *
 166 * The data for this chart is taken from Table 5 of the CS4270 reference
 167 * manual.
 168 *
 169 * This table is used to determine how to program the Mode Control register.
 170 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
 171 * rates the CS4270 currently supports.
 172 *
 173 * @speed_mode is the corresponding bit pattern to be written to the
 174 * MODE bits of the Mode Control Register
 175 *
 176 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
 177 * the Mode Control Register.
 178 *
 179 * In situations where a single ratio is represented by multiple speed
 180 * modes, we favor the slowest speed.  E.g, for a ratio of 128, we pick
 181 * double-speed instead of quad-speed.  However, the CS4270 errata states
 182 * that divide-By-1.5 can cause failures, so we avoid that mode where
 183 * possible.
 184 *
 185 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
 186 * work if Vd is 3.3V.  If this effects you, select the
 187 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
 188 * never select any sample rates that require divide-by-1.5.
 189 */
 190struct cs4270_mode_ratios {
 191        unsigned int ratio;
 192        u8 speed_mode;
 193        u8 mclk;
 194};
 195
 196static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
 197        {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
 198#ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
 199        {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
 200#endif
 201        {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
 202        {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
 203        {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
 204        {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
 205        {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
 206        {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
 207        {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
 208};
 209
 210/* The number of MCLK/LRCK ratios supported by the CS4270 */
 211#define NUM_MCLK_RATIOS         ARRAY_SIZE(cs4270_mode_ratios)
 212
 213static bool cs4270_reg_is_readable(struct device *dev, unsigned int reg)
 214{
 215        return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG);
 216}
 217
 218static bool cs4270_reg_is_volatile(struct device *dev, unsigned int reg)
 219{
 220        /* Unreadable registers are considered volatile */
 221        if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
 222                return 1;
 223
 224        return reg == CS4270_CHIPID;
 225}
 226
 227/**
 228 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
 229 * @codec_dai: the codec DAI
 230 * @clk_id: the clock ID (ignored)
 231 * @freq: the MCLK input frequency
 232 * @dir: the clock direction (ignored)
 233 *
 234 * This function is used to tell the codec driver what the input MCLK
 235 * frequency is.
 236 *
 237 * The value of MCLK is used to determine which sample rates are supported
 238 * by the CS4270.  The ratio of MCLK / Fs must be equal to one of nine
 239 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
 240 *
 241 * This function calculates the nine ratios and determines which ones match
 242 * a standard sample rate.  If there's a match, then it is added to the list
 243 * of supported sample rates.
 244 *
 245 * This function must be called by the machine driver's 'startup' function,
 246 * otherwise the list of supported sample rates will not be available in
 247 * time for ALSA.
 248 *
 249 * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
 250 * theoretically possible sample rates to be enabled. Call it again with a
 251 * proper value set one the external clock is set (most probably you would do
 252 * that from a machine's driver 'hw_param' hook.
 253 */
 254static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 255                                 int clk_id, unsigned int freq, int dir)
 256{
 257        struct snd_soc_codec *codec = codec_dai->codec;
 258        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 259
 260        cs4270->mclk = freq;
 261        return 0;
 262}
 263
 264/**
 265 * cs4270_set_dai_fmt - configure the codec for the selected audio format
 266 * @codec_dai: the codec DAI
 267 * @format: a SND_SOC_DAIFMT_x value indicating the data format
 268 *
 269 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
 270 * codec accordingly.
 271 *
 272 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
 273 * SND_SOC_DAIFMT_LEFT_J.  The CS4270 codec also supports right-justified
 274 * data for playback only, but ASoC currently does not support different
 275 * formats for playback vs. record.
 276 */
 277static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
 278                              unsigned int format)
 279{
 280        struct snd_soc_codec *codec = codec_dai->codec;
 281        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 282
 283        /* set DAI format */
 284        switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
 285        case SND_SOC_DAIFMT_I2S:
 286        case SND_SOC_DAIFMT_LEFT_J:
 287                cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
 288                break;
 289        default:
 290                dev_err(codec->dev, "invalid dai format\n");
 291                return -EINVAL;
 292        }
 293
 294        /* set master/slave audio interface */
 295        switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
 296        case SND_SOC_DAIFMT_CBS_CFS:
 297                cs4270->slave_mode = 1;
 298                break;
 299        case SND_SOC_DAIFMT_CBM_CFM:
 300                cs4270->slave_mode = 0;
 301                break;
 302        default:
 303                /* all other modes are unsupported by the hardware */
 304                dev_err(codec->dev, "Unknown master/slave configuration\n");
 305                return -EINVAL;
 306        }
 307
 308        return 0;
 309}
 310
 311/**
 312 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
 313 * @substream: the audio stream
 314 * @params: the hardware parameters to set
 315 * @dai: the SOC DAI (ignored)
 316 *
 317 * This function programs the hardware with the values provided.
 318 * Specifically, the sample rate and the data format.
 319 *
 320 * The .ops functions are used to provide board-specific data, like input
 321 * frequencies, to this driver.  This function takes that information,
 322 * combines it with the hardware parameters provided, and programs the
 323 * hardware accordingly.
 324 */
 325static int cs4270_hw_params(struct snd_pcm_substream *substream,
 326                            struct snd_pcm_hw_params *params,
 327                            struct snd_soc_dai *dai)
 328{
 329        struct snd_soc_codec *codec = dai->codec;
 330        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 331        int ret;
 332        unsigned int i;
 333        unsigned int rate;
 334        unsigned int ratio;
 335        int reg;
 336
 337        /* Figure out which MCLK/LRCK ratio to use */
 338
 339        rate = params_rate(params);     /* Sampling rate, in Hz */
 340        ratio = cs4270->mclk / rate;    /* MCLK/LRCK ratio */
 341
 342        for (i = 0; i < NUM_MCLK_RATIOS; i++) {
 343                if (cs4270_mode_ratios[i].ratio == ratio)
 344                        break;
 345        }
 346
 347        if (i == NUM_MCLK_RATIOS) {
 348                /* We did not find a matching ratio */
 349                dev_err(codec->dev, "could not find matching ratio\n");
 350                return -EINVAL;
 351        }
 352
 353        /* Set the sample rate */
 354
 355        reg = snd_soc_read(codec, CS4270_MODE);
 356        reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
 357        reg |= cs4270_mode_ratios[i].mclk;
 358
 359        if (cs4270->slave_mode)
 360                reg |= CS4270_MODE_SLAVE;
 361        else
 362                reg |= cs4270_mode_ratios[i].speed_mode;
 363
 364        ret = snd_soc_write(codec, CS4270_MODE, reg);
 365        if (ret < 0) {
 366                dev_err(codec->dev, "i2c write failed\n");
 367                return ret;
 368        }
 369
 370        /* Set the DAI format */
 371
 372        reg = snd_soc_read(codec, CS4270_FORMAT);
 373        reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
 374
 375        switch (cs4270->mode) {
 376        case SND_SOC_DAIFMT_I2S:
 377                reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
 378                break;
 379        case SND_SOC_DAIFMT_LEFT_J:
 380                reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
 381                break;
 382        default:
 383                dev_err(codec->dev, "unknown dai format\n");
 384                return -EINVAL;
 385        }
 386
 387        ret = snd_soc_write(codec, CS4270_FORMAT, reg);
 388        if (ret < 0) {
 389                dev_err(codec->dev, "i2c write failed\n");
 390                return ret;
 391        }
 392
 393        return ret;
 394}
 395
 396/**
 397 * cs4270_dai_mute - enable/disable the CS4270 external mute
 398 * @dai: the SOC DAI
 399 * @mute: 0 = disable mute, 1 = enable mute
 400 *
 401 * This function toggles the mute bits in the MUTE register.  The CS4270's
 402 * mute capability is intended for external muting circuitry, so if the
 403 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
 404 * then this function will do nothing.
 405 */
 406static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
 407{
 408        struct snd_soc_codec *codec = dai->codec;
 409        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 410        int reg6;
 411
 412        reg6 = snd_soc_read(codec, CS4270_MUTE);
 413
 414        if (mute)
 415                reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
 416        else {
 417                reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
 418                reg6 |= cs4270->manual_mute;
 419        }
 420
 421        return snd_soc_write(codec, CS4270_MUTE, reg6);
 422}
 423
 424/**
 425 * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
 426 *                       alsa control.
 427 * @kcontrol: mixer control
 428 * @ucontrol: control element information
 429 *
 430 * This function basically passes the arguments on to the generic
 431 * snd_soc_put_volsw() function and saves the mute information in
 432 * our private data structure. This is because we want to prevent
 433 * cs4270_dai_mute() neglecting the user's decision to manually
 434 * mute the codec's output.
 435 *
 436 * Returns 0 for success.
 437 */
 438static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
 439                                struct snd_ctl_elem_value *ucontrol)
 440{
 441        struct snd_soc_codec *codec = snd_soc_kcontrol_codec(kcontrol);
 442        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 443        int left = !ucontrol->value.integer.value[0];
 444        int right = !ucontrol->value.integer.value[1];
 445
 446        cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
 447                              (right ? CS4270_MUTE_DAC_B : 0);
 448
 449        return snd_soc_put_volsw(kcontrol, ucontrol);
 450}
 451
 452/* A list of non-DAPM controls that the CS4270 supports */
 453static const struct snd_kcontrol_new cs4270_snd_controls[] = {
 454        SOC_DOUBLE_R("Master Playback Volume",
 455                CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
 456        SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
 457        SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
 458        SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
 459        SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
 460        SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
 461        SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
 462        SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
 463        SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
 464                snd_soc_get_volsw, cs4270_soc_put_mute),
 465};
 466
 467static const struct snd_soc_dai_ops cs4270_dai_ops = {
 468        .hw_params      = cs4270_hw_params,
 469        .set_sysclk     = cs4270_set_dai_sysclk,
 470        .set_fmt        = cs4270_set_dai_fmt,
 471        .digital_mute   = cs4270_dai_mute,
 472};
 473
 474static struct snd_soc_dai_driver cs4270_dai = {
 475        .name = "cs4270-hifi",
 476        .playback = {
 477                .stream_name = "Playback",
 478                .channels_min = 2,
 479                .channels_max = 2,
 480                .rates = SNDRV_PCM_RATE_CONTINUOUS,
 481                .rate_min = 4000,
 482                .rate_max = 216000,
 483                .formats = CS4270_FORMATS,
 484        },
 485        .capture = {
 486                .stream_name = "Capture",
 487                .channels_min = 2,
 488                .channels_max = 2,
 489                .rates = SNDRV_PCM_RATE_CONTINUOUS,
 490                .rate_min = 4000,
 491                .rate_max = 216000,
 492                .formats = CS4270_FORMATS,
 493        },
 494        .ops = &cs4270_dai_ops,
 495};
 496
 497/**
 498 * cs4270_probe - ASoC probe function
 499 * @pdev: platform device
 500 *
 501 * This function is called when ASoC has all the pieces it needs to
 502 * instantiate a sound driver.
 503 */
 504static int cs4270_probe(struct snd_soc_codec *codec)
 505{
 506        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 507        int ret;
 508
 509        /* Disable auto-mute.  This feature appears to be buggy.  In some
 510         * situations, auto-mute will not deactivate when it should, so we want
 511         * this feature disabled by default.  An application (e.g. alsactl) can
 512         * re-enabled it by using the controls.
 513         */
 514        ret = snd_soc_update_bits(codec, CS4270_MUTE, CS4270_MUTE_AUTO, 0);
 515        if (ret < 0) {
 516                dev_err(codec->dev, "i2c write failed\n");
 517                return ret;
 518        }
 519
 520        /* Disable automatic volume control.  The hardware enables, and it
 521         * causes volume change commands to be delayed, sometimes until after
 522         * playback has started.  An application (e.g. alsactl) can
 523         * re-enabled it by using the controls.
 524         */
 525        ret = snd_soc_update_bits(codec, CS4270_TRANS,
 526                CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0);
 527        if (ret < 0) {
 528                dev_err(codec->dev, "i2c write failed\n");
 529                return ret;
 530        }
 531
 532        ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 533                                    cs4270->supplies);
 534
 535        return ret;
 536}
 537
 538/**
 539 * cs4270_remove - ASoC remove function
 540 * @pdev: platform device
 541 *
 542 * This function is the counterpart to cs4270_probe().
 543 */
 544static int cs4270_remove(struct snd_soc_codec *codec)
 545{
 546        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 547
 548        regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
 549
 550        return 0;
 551};
 552
 553#ifdef CONFIG_PM
 554
 555/* This suspend/resume implementation can handle both - a simple standby
 556 * where the codec remains powered, and a full suspend, where the voltage
 557 * domain the codec is connected to is teared down and/or any other hardware
 558 * reset condition is asserted.
 559 *
 560 * The codec's own power saving features are enabled in the suspend callback,
 561 * and all registers are written back to the hardware when resuming.
 562 */
 563
 564static int cs4270_soc_suspend(struct snd_soc_codec *codec)
 565{
 566        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 567        int reg, ret;
 568
 569        reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
 570        if (reg < 0)
 571                return reg;
 572
 573        ret = snd_soc_write(codec, CS4270_PWRCTL, reg);
 574        if (ret < 0)
 575                return ret;
 576
 577        regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
 578                               cs4270->supplies);
 579
 580        return 0;
 581}
 582
 583static int cs4270_soc_resume(struct snd_soc_codec *codec)
 584{
 585        struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
 586        int reg, ret;
 587
 588        ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 589                                    cs4270->supplies);
 590        if (ret != 0)
 591                return ret;
 592
 593        /* In case the device was put to hard reset during sleep, we need to
 594         * wait 500ns here before any I2C communication. */
 595        ndelay(500);
 596
 597        /* first restore the entire register cache ... */
 598        regcache_sync(cs4270->regmap);
 599
 600        /* ... then disable the power-down bits */
 601        reg = snd_soc_read(codec, CS4270_PWRCTL);
 602        reg &= ~CS4270_PWRCTL_PDN_ALL;
 603
 604        return snd_soc_write(codec, CS4270_PWRCTL, reg);
 605}
 606#else
 607#define cs4270_soc_suspend      NULL
 608#define cs4270_soc_resume       NULL
 609#endif /* CONFIG_PM */
 610
 611/*
 612 * ASoC codec driver structure
 613 */
 614static const struct snd_soc_codec_driver soc_codec_device_cs4270 = {
 615        .probe =                cs4270_probe,
 616        .remove =               cs4270_remove,
 617        .suspend =              cs4270_soc_suspend,
 618        .resume =               cs4270_soc_resume,
 619
 620        .controls =             cs4270_snd_controls,
 621        .num_controls =         ARRAY_SIZE(cs4270_snd_controls),
 622        .dapm_widgets =         cs4270_dapm_widgets,
 623        .num_dapm_widgets =     ARRAY_SIZE(cs4270_dapm_widgets),
 624        .dapm_routes =          cs4270_dapm_routes,
 625        .num_dapm_routes =      ARRAY_SIZE(cs4270_dapm_routes),
 626};
 627
 628/*
 629 * cs4270_of_match - the device tree bindings
 630 */
 631static const struct of_device_id cs4270_of_match[] = {
 632        { .compatible = "cirrus,cs4270", },
 633        { }
 634};
 635MODULE_DEVICE_TABLE(of, cs4270_of_match);
 636
 637static const struct regmap_config cs4270_regmap = {
 638        .reg_bits =             8,
 639        .val_bits =             8,
 640        .max_register =         CS4270_LASTREG,
 641        .reg_defaults =         cs4270_reg_defaults,
 642        .num_reg_defaults =     ARRAY_SIZE(cs4270_reg_defaults),
 643        .cache_type =           REGCACHE_RBTREE,
 644
 645        .readable_reg =         cs4270_reg_is_readable,
 646        .volatile_reg =         cs4270_reg_is_volatile,
 647};
 648
 649/**
 650 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
 651 * @i2c_client: the I2C client object
 652 * @id: the I2C device ID (ignored)
 653 *
 654 * This function is called whenever the I2C subsystem finds a device that
 655 * matches the device ID given via a prior call to i2c_add_driver().
 656 */
 657static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 658        const struct i2c_device_id *id)
 659{
 660        struct device_node *np = i2c_client->dev.of_node;
 661        struct cs4270_private *cs4270;
 662        unsigned int val;
 663        int ret, i;
 664
 665        cs4270 = devm_kzalloc(&i2c_client->dev, sizeof(struct cs4270_private),
 666                              GFP_KERNEL);
 667        if (!cs4270)
 668                return -ENOMEM;
 669
 670        /* get the power supply regulators */
 671        for (i = 0; i < ARRAY_SIZE(supply_names); i++)
 672                cs4270->supplies[i].supply = supply_names[i];
 673
 674        ret = devm_regulator_bulk_get(&i2c_client->dev,
 675                                      ARRAY_SIZE(cs4270->supplies),
 676                                      cs4270->supplies);
 677        if (ret < 0)
 678                return ret;
 679
 680        /* See if we have a way to bring the codec out of reset */
 681        if (np) {
 682                enum of_gpio_flags flags;
 683                int gpio = of_get_named_gpio_flags(np, "reset-gpio", 0, &flags);
 684
 685                if (gpio_is_valid(gpio)) {
 686                        ret = devm_gpio_request_one(&i2c_client->dev, gpio,
 687                                     flags & OF_GPIO_ACTIVE_LOW ?
 688                                        GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
 689                                     "cs4270 reset");
 690                        if (ret < 0)
 691                                return ret;
 692                }
 693        }
 694
 695        cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
 696        if (IS_ERR(cs4270->regmap))
 697                return PTR_ERR(cs4270->regmap);
 698
 699        /* Verify that we have a CS4270 */
 700        ret = regmap_read(cs4270->regmap, CS4270_CHIPID, &val);
 701        if (ret < 0) {
 702                dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
 703                       i2c_client->addr);
 704                return ret;
 705        }
 706        /* The top four bits of the chip ID should be 1100. */
 707        if ((val & 0xF0) != 0xC0) {
 708                dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
 709                       i2c_client->addr);
 710                return -ENODEV;
 711        }
 712
 713        dev_info(&i2c_client->dev, "found device at i2c address %X\n",
 714                i2c_client->addr);
 715        dev_info(&i2c_client->dev, "hardware revision %X\n", val & 0xF);
 716
 717        i2c_set_clientdata(i2c_client, cs4270);
 718
 719        ret = snd_soc_register_codec(&i2c_client->dev,
 720                        &soc_codec_device_cs4270, &cs4270_dai, 1);
 721        return ret;
 722}
 723
 724/**
 725 * cs4270_i2c_remove - remove an I2C device
 726 * @i2c_client: the I2C client object
 727 *
 728 * This function is the counterpart to cs4270_i2c_probe().
 729 */
 730static int cs4270_i2c_remove(struct i2c_client *i2c_client)
 731{
 732        snd_soc_unregister_codec(&i2c_client->dev);
 733        return 0;
 734}
 735
 736/*
 737 * cs4270_id - I2C device IDs supported by this driver
 738 */
 739static const struct i2c_device_id cs4270_id[] = {
 740        {"cs4270", 0},
 741        {}
 742};
 743MODULE_DEVICE_TABLE(i2c, cs4270_id);
 744
 745/*
 746 * cs4270_i2c_driver - I2C device identification
 747 *
 748 * This structure tells the I2C subsystem how to identify and support a
 749 * given I2C device type.
 750 */
 751static struct i2c_driver cs4270_i2c_driver = {
 752        .driver = {
 753                .name = "cs4270",
 754                .owner = THIS_MODULE,
 755                .of_match_table = cs4270_of_match,
 756        },
 757        .id_table = cs4270_id,
 758        .probe = cs4270_i2c_probe,
 759        .remove = cs4270_i2c_remove,
 760};
 761
 762module_i2c_driver(cs4270_i2c_driver);
 763
 764MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
 765MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
 766MODULE_LICENSE("GPL");
 767