sound/soc/codecs/cs4270.c

   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/platform_device.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
  33 #include "cs4270.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 static const char *supply_names[] = {
 111         "va", "vd", "vlc"
 112 };
 113
 114 /* Private data for the CS4270 */
 115 struct cs4270_private {
 116         struct snd_soc_codec codec;
 117         u8 reg_cache[CS4270_NUMREGS];
 118         unsigned int mclk; /* Input frequency of the MCLK pin */
 119         unsigned int mode; /* The mode (I2S or left-justified) */
 120         unsigned int slave_mode;
 121         unsigned int manual_mute;
 122
 123         /* power domain regulators */
 124         struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
 125 };
 126
 127 /**
 128  * struct cs4270_mode_ratios - clock ratio tables
 129  * @ratio: the ratio of MCLK to the sample rate
 130  * @speed_mode: the Speed Mode bits to set in the Mode Control register for
 131  *              this ratio
 132  * @mclk: the Ratio Select bits to set in the Mode Control register for this
 133  *        ratio
 134  *
 135  * The data for this chart is taken from Table 5 of the CS4270 reference
 136  * manual.
 137  *
 138  * This table is used to determine how to program the Mode Control register.
 139  * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
 140  * rates the CS4270 currently supports.
 141  *
 142  * @speed_mode is the corresponding bit pattern to be written to the
 143  * MODE bits of the Mode Control Register
 144  *
 145  * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
 146  * the Mode Control Register.
 147  *
 148  * In situations where a single ratio is represented by multiple speed
 149  * modes, we favor the slowest speed.  E.g, for a ratio of 128, we pick
 150  * double-speed instead of quad-speed.  However, the CS4270 errata states
 151  * that divide-By-1.5 can cause failures, so we avoid that mode where
 152  * possible.
 153  *
 154  * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
 155  * work if Vd is 3.3V.  If this effects you, select the
 156  * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
 157  * never select any sample rates that require divide-by-1.5.
 158  */
 159 struct cs4270_mode_ratios {
 160         unsigned int ratio;
 161         u8 speed_mode;
 162         u8 mclk;
 163 };
 164
 165 static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
 166         {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
 167 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
 168         {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
 169 #endif
 170         {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
 171         {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
 172         {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
 173         {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
 174         {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
 175         {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
 176         {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
 177 };
 178
 179 /* The number of MCLK/LRCK ratios supported by the CS4270 */
 180 #define NUM_MCLK_RATIOS         ARRAY_SIZE(cs4270_mode_ratios)
 181
 182 /**
 183  * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
 184  * @codec_dai: the codec DAI
 185  * @clk_id: the clock ID (ignored)
 186  * @freq: the MCLK input frequency
 187  * @dir: the clock direction (ignored)
 188  *
 189  * This function is used to tell the codec driver what the input MCLK
 190  * frequency is.
 191  *
 192  * The value of MCLK is used to determine which sample rates are supported
 193  * by the CS4270.  The ratio of MCLK / Fs must be equal to one of nine
 194  * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
 195  *
 196  * This function calculates the nine ratios and determines which ones match
 197  * a standard sample rate.  If there's a match, then it is added to the list
 198  * of supported sample rates.
 199  *
 200  * This function must be called by the machine driver's 'startup' function,
 201  * otherwise the list of supported sample rates will not be available in
 202  * time for ALSA.
 203  *
 204  * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
 205  * theoretically possible sample rates to be enabled. Call it again with a
 206  * proper value set one the external clock is set (most probably you would do
 207  * that from a machine's driver 'hw_param' hook.
 208  */
 209 static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 210                                  int clk_id, unsigned int freq, int dir)
 211 {
 212         struct snd_soc_codec *codec = codec_dai->codec;
 213         struct cs4270_private *cs4270 = codec->private_data;
 214         unsigned int rates = 0;
 215         unsigned int rate_min = -1;
 216         unsigned int rate_max = 0;
 217         unsigned int i;
 218
 219         cs4270->mclk = freq;
 220
 221         if (cs4270->mclk) {
 222                 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
 223                         unsigned int rate = freq / cs4270_mode_ratios[i].ratio;
 224                         rates |= snd_pcm_rate_to_rate_bit(rate);
 225                         if (rate < rate_min)
 226                                 rate_min = rate;
 227                         if (rate > rate_max)
 228                                 rate_max = rate;
 229                 }
 230                 /* FIXME: soc should support a rate list */
 231                 rates &= ~SNDRV_PCM_RATE_KNOT;
 232
 233                 if (!rates) {
 234                         dev_err(codec->dev, "could not find a valid sample rate\n");
 235                         return -EINVAL;
 236                 }
 237         } else {
 238                 /* enable all possible rates */
 239                 rates = SNDRV_PCM_RATE_8000_192000;
 240                 rate_min = 8000;
 241                 rate_max = 192000;
 242         }
 243
 244         codec_dai->playback.rates = rates;
 245         codec_dai->playback.rate_min = rate_min;
 246         codec_dai->playback.rate_max = rate_max;
 247
 248         codec_dai->capture.rates = rates;
 249         codec_dai->capture.rate_min = rate_min;
 250         codec_dai->capture.rate_max = rate_max;
 251
 252         return 0;
 253 }
 254
 255 /**
 256  * cs4270_set_dai_fmt - configure the codec for the selected audio format
 257  * @codec_dai: the codec DAI
 258  * @format: a SND_SOC_DAIFMT_x value indicating the data format
 259  *
 260  * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
 261  * codec accordingly.
 262  *
 263  * Currently, this function only supports SND_SOC_DAIFMT_I2S and
 264  * SND_SOC_DAIFMT_LEFT_J.  The CS4270 codec also supports right-justified
 265  * data for playback only, but ASoC currently does not support different
 266  * formats for playback vs. record.
 267  */
 268 static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
 269                               unsigned int format)
 270 {
 271         struct snd_soc_codec *codec = codec_dai->codec;
 272         struct cs4270_private *cs4270 = codec->private_data;
 273         int ret = 0;
 274
 275         /* set DAI format */
 276         switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
 277         case SND_SOC_DAIFMT_I2S:
 278         case SND_SOC_DAIFMT_LEFT_J:
 279                 cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
 280                 break;
 281         default:
 282                 dev_err(codec->dev, "invalid dai format\n");
 283                 ret = -EINVAL;
 284         }
 285
 286         /* set master/slave audio interface */
 287         switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
 288         case SND_SOC_DAIFMT_CBS_CFS:
 289                 cs4270->slave_mode = 1;
 290                 break;
 291         case SND_SOC_DAIFMT_CBM_CFM:
 292                 cs4270->slave_mode = 0;
 293                 break;
 294         default:
 295                 /* all other modes are unsupported by the hardware */
 296                 ret = -EINVAL;
 297         }
 298
 299         return ret;
 300 }
 301
 302 /**
 303  * cs4270_fill_cache - pre-fill the CS4270 register cache.
 304  * @codec: the codec for this CS4270
 305  *
 306  * This function fills in the CS4270 register cache by reading the register
 307  * values from the hardware.
 308  *
 309  * This CS4270 registers are cached to avoid excessive I2C I/O operations.
 310  * After the initial read to pre-fill the cache, the CS4270 never updates
 311  * the register values, so we won't have a cache coherency problem.
 312  *
 313  * We use the auto-increment feature of the CS4270 to read all registers in
 314  * one shot.
 315  */
 316 static int cs4270_fill_cache(struct snd_soc_codec *codec)
 317 {
 318         u8 *cache = codec->reg_cache;
 319         struct i2c_client *i2c_client = codec->control_data;
 320         s32 length;
 321
 322         length = i2c_smbus_read_i2c_block_data(i2c_client,
 323                 CS4270_FIRSTREG | CS4270_I2C_INCR, CS4270_NUMREGS, cache);
 324
 325         if (length != CS4270_NUMREGS) {
 326                 dev_err(codec->dev, "i2c read failure, addr=0x%x\n",
 327                        i2c_client->addr);
 328                 return -EIO;
 329         }
 330
 331         return 0;
 332 }
 333
 334 /**
 335  * cs4270_read_reg_cache - read from the CS4270 register cache.
 336  * @codec: the codec for this CS4270
 337  * @reg: the register to read
 338  *
 339  * This function returns the value for a given register.  It reads only from
 340  * the register cache, not the hardware itself.
 341  *
 342  * This CS4270 registers are cached to avoid excessive I2C I/O operations.
 343  * After the initial read to pre-fill the cache, the CS4270 never updates
 344  * the register values, so we won't have a cache coherency problem.
 345  */
 346 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec *codec,
 347         unsigned int reg)
 348 {
 349         u8 *cache = codec->reg_cache;
 350
 351         if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
 352                 return -EIO;
 353
 354         return cache[reg - CS4270_FIRSTREG];
 355 }
 356
 357 /**
 358  * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
 359  * @codec: the codec for this CS4270
 360  * @reg: the register to write
 361  * @value: the value to write to the register
 362  *
 363  * This function writes the given value to the given CS4270 register, and
 364  * also updates the register cache.
 365  *
 366  * Note that we don't use the hw_write function pointer of snd_soc_codec.
 367  * That's because it's too clunky: the hw_write_t prototype does not match
 368  * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
 369  */
 370 static int cs4270_i2c_write(struct snd_soc_codec *codec, unsigned int reg,
 371                             unsigned int value)
 372 {
 373         u8 *cache = codec->reg_cache;
 374
 375         if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
 376                 return -EIO;
 377
 378         /* Only perform an I2C operation if the new value is different */
 379         if (cache[reg - CS4270_FIRSTREG] != value) {
 380                 struct i2c_client *client = codec->control_data;
 381                 if (i2c_smbus_write_byte_data(client, reg, value)) {
 382                         dev_err(codec->dev, "i2c write failed\n");
 383                         return -EIO;
 384                 }
 385
 386                 /* We've written to the hardware, so update the cache */
 387                 cache[reg - CS4270_FIRSTREG] = value;
 388         }
 389
 390         return 0;
 391 }
 392
 393 /**
 394  * cs4270_hw_params - program the CS4270 with the given hardware parameters.
 395  * @substream: the audio stream
 396  * @params: the hardware parameters to set
 397  * @dai: the SOC DAI (ignored)
 398  *
 399  * This function programs the hardware with the values provided.
 400  * Specifically, the sample rate and the data format.
 401  *
 402  * The .ops functions are used to provide board-specific data, like input
 403  * frequencies, to this driver.  This function takes that information,
 404  * combines it with the hardware parameters provided, and programs the
 405  * hardware accordingly.
 406  */
 407 static int cs4270_hw_params(struct snd_pcm_substream *substream,
 408                             struct snd_pcm_hw_params *params,
 409                             struct snd_soc_dai *dai)
 410 {
 411         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 412         struct snd_soc_device *socdev = rtd->socdev;
 413         struct snd_soc_codec *codec = socdev->card->codec;
 414         struct cs4270_private *cs4270 = codec->private_data;
 415         int ret;
 416         unsigned int i;
 417         unsigned int rate;
 418         unsigned int ratio;
 419         int reg;
 420
 421         /* Figure out which MCLK/LRCK ratio to use */
 422
 423         rate = params_rate(params);     /* Sampling rate, in Hz */
 424         ratio = cs4270->mclk / rate;    /* MCLK/LRCK ratio */
 425
 426         for (i = 0; i < NUM_MCLK_RATIOS; i++) {
 427                 if (cs4270_mode_ratios[i].ratio == ratio)
 428                         break;
 429         }
 430
 431         if (i == NUM_MCLK_RATIOS) {
 432                 /* We did not find a matching ratio */
 433                 dev_err(codec->dev, "could not find matching ratio\n");
 434                 return -EINVAL;
 435         }
 436
 437         /* Set the sample rate */
 438
 439         reg = snd_soc_read(codec, CS4270_MODE);
 440         reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
 441         reg |= cs4270_mode_ratios[i].mclk;
 442
 443         if (cs4270->slave_mode)
 444                 reg |= CS4270_MODE_SLAVE;
 445         else
 446                 reg |= cs4270_mode_ratios[i].speed_mode;
 447
 448         ret = snd_soc_write(codec, CS4270_MODE, reg);
 449         if (ret < 0) {
 450                 dev_err(codec->dev, "i2c write failed\n");
 451                 return ret;
 452         }
 453
 454         /* Set the DAI format */
 455
 456         reg = snd_soc_read(codec, CS4270_FORMAT);
 457         reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
 458
 459         switch (cs4270->mode) {
 460         case SND_SOC_DAIFMT_I2S:
 461                 reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
 462                 break;
 463         case SND_SOC_DAIFMT_LEFT_J:
 464                 reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
 465                 break;
 466         default:
 467                 dev_err(codec->dev, "unknown dai format\n");
 468                 return -EINVAL;
 469         }
 470
 471         ret = snd_soc_write(codec, CS4270_FORMAT, reg);
 472         if (ret < 0) {
 473                 dev_err(codec->dev, "i2c write failed\n");
 474                 return ret;
 475         }
 476
 477         return ret;
 478 }
 479
 480 /**
 481  * cs4270_dai_mute - enable/disable the CS4270 external mute
 482  * @dai: the SOC DAI
 483  * @mute: 0 = disable mute, 1 = enable mute
 484  *
 485  * This function toggles the mute bits in the MUTE register.  The CS4270's
 486  * mute capability is intended for external muting circuitry, so if the
 487  * board does not have the MUTEA or MUTEB pins connected to such circuitry,
 488  * then this function will do nothing.
 489  */
 490 static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
 491 {
 492         struct snd_soc_codec *codec = dai->codec;
 493         struct cs4270_private *cs4270 = codec->private_data;
 494         int reg6;
 495
 496         reg6 = snd_soc_read(codec, CS4270_MUTE);
 497
 498         if (mute)
 499                 reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
 500         else {
 501                 reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
 502                 reg6 |= cs4270->manual_mute;
 503         }
 504
 505         return snd_soc_write(codec, CS4270_MUTE, reg6);
 506 }
 507
 508 /**
 509  * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
 510  *                       alsa control.
 511  * @kcontrol: mixer control
 512  * @ucontrol: control element information
 513  *
 514  * This function basically passes the arguments on to the generic
 515  * snd_soc_put_volsw() function and saves the mute information in
 516  * our private data structure. This is because we want to prevent
 517  * cs4270_dai_mute() neglecting the user's decision to manually
 518  * mute the codec's output.
 519  *
 520  * Returns 0 for success.
 521  */
 522 static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
 523                                 struct snd_ctl_elem_value *ucontrol)
 524 {
 525         struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
 526         struct cs4270_private *cs4270 = codec->private_data;
 527         int left = !ucontrol->value.integer.value[0];
 528         int right = !ucontrol->value.integer.value[1];
 529
 530         cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
 531                               (right ? CS4270_MUTE_DAC_B : 0);
 532
 533         return snd_soc_put_volsw(kcontrol, ucontrol);
 534 }
 535
 536 /* A list of non-DAPM controls that the CS4270 supports */
 537 static const struct snd_kcontrol_new cs4270_snd_controls[] = {
 538         SOC_DOUBLE_R("Master Playback Volume",
 539                 CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
 540         SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
 541         SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
 542         SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
 543         SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
 544         SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
 545         SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
 546         SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
 547         SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
 548                 snd_soc_get_volsw, cs4270_soc_put_mute),
 549 };
 550
 551 /*
 552  * cs4270_codec - global variable to store codec for the ASoC probe function
 553  *
 554  * If struct i2c_driver had a private_data field, we wouldn't need to use
 555  * cs4270_codec.  This is the only way to pass the codec structure from
 556  * cs4270_i2c_probe() to cs4270_probe().  Unfortunately, there is no good
 557  * way to synchronize these two functions.  cs4270_i2c_probe() can be called
 558  * multiple times before cs4270_probe() is called even once.  So for now, we
 559  * also only allow cs4270_i2c_probe() to be run once.  That means that we do
 560  * not support more than one cs4270 device in the system, at least for now.
 561  */
 562 static struct snd_soc_codec *cs4270_codec;
 563
 564 static struct snd_soc_dai_ops cs4270_dai_ops = {
 565         .hw_params      = cs4270_hw_params,
 566         .set_sysclk     = cs4270_set_dai_sysclk,
 567         .set_fmt        = cs4270_set_dai_fmt,
 568         .digital_mute   = cs4270_dai_mute,
 569 };
 570
 571 struct snd_soc_dai cs4270_dai = {
 572         .name = "cs4270",
 573         .playback = {
 574                 .stream_name = "Playback",
 575                 .channels_min = 1,
 576                 .channels_max = 2,
 577                 .rates = 0,
 578                 .formats = CS4270_FORMATS,
 579         },
 580         .capture = {
 581                 .stream_name = "Capture",
 582                 .channels_min = 1,
 583                 .channels_max = 2,
 584                 .rates = 0,
 585                 .formats = CS4270_FORMATS,
 586         },
 587         .ops = &cs4270_dai_ops,
 588 };
 589 EXPORT_SYMBOL_GPL(cs4270_dai);
 590
 591 /**
 592  * cs4270_probe - ASoC probe function
 593  * @pdev: platform device
 594  *
 595  * This function is called when ASoC has all the pieces it needs to
 596  * instantiate a sound driver.
 597  */
 598 static int cs4270_probe(struct platform_device *pdev)
 599 {
 600         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 601         struct snd_soc_codec *codec = cs4270_codec;
 602         struct cs4270_private *cs4270 = codec->private_data;
 603         int i, ret;
 604
 605         /* Connect the codec to the socdev.  snd_soc_new_pcms() needs this. */
 606         socdev->card->codec = codec;
 607
 608         /* Register PCMs */
 609         ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
 610         if (ret < 0) {
 611                 dev_err(codec->dev, "failed to create pcms\n");
 612                 return ret;
 613         }
 614
 615         /* Add the non-DAPM controls */
 616         ret = snd_soc_add_controls(codec, cs4270_snd_controls,
 617                                 ARRAY_SIZE(cs4270_snd_controls));
 618         if (ret < 0) {
 619                 dev_err(codec->dev, "failed to add controls\n");
 620                 goto error_free_pcms;
 621         }
 622
 623         /* get the power supply regulators */
 624         for (i = 0; i < ARRAY_SIZE(supply_names); i++)
 625                 cs4270->supplies[i].supply = supply_names[i];
 626
 627         ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(cs4270->supplies),
 628                                  cs4270->supplies);
 629         if (ret < 0)
 630                 goto error_free_pcms;
 631
 632         ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 633                                     cs4270->supplies);
 634         if (ret < 0)
 635                 goto error_free_regulators;
 636
 637         return 0;
 638
 639 error_free_regulators:
 640         regulator_bulk_free(ARRAY_SIZE(cs4270->supplies),
 641                             cs4270->supplies);
 642
 643 error_free_pcms:
 644         snd_soc_free_pcms(socdev);
 645
 646         return ret;
 647 }
 648
 649 /**
 650  * cs4270_remove - ASoC remove function
 651  * @pdev: platform device
 652  *
 653  * This function is the counterpart to cs4270_probe().
 654  */
 655 static int cs4270_remove(struct platform_device *pdev)
 656 {
 657         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 658         struct snd_soc_codec *codec = cs4270_codec;
 659         struct cs4270_private *cs4270 = codec->private_data;
 660
 661         snd_soc_free_pcms(socdev);
 662         regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
 663         regulator_bulk_free(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
 664
 665         return 0;
 666 };
 667
 668 /**
 669  * cs4270_i2c_probe - initialize the I2C interface of the CS4270
 670  * @i2c_client: the I2C client object
 671  * @id: the I2C device ID (ignored)
 672  *
 673  * This function is called whenever the I2C subsystem finds a device that
 674  * matches the device ID given via a prior call to i2c_add_driver().
 675  */
 676 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 677         const struct i2c_device_id *id)
 678 {
 679         struct snd_soc_codec *codec;
 680         struct cs4270_private *cs4270;
 681         unsigned int reg;
 682         int ret;
 683
 684         /* For now, we only support one cs4270 device in the system.  See the
 685          * comment for cs4270_codec.
 686          */
 687         if (cs4270_codec) {
 688                 dev_err(&i2c_client->dev, "ignoring CS4270 at addr %X\n",
 689                        i2c_client->addr);
 690                 dev_err(&i2c_client->dev, "only one per board allowed\n");
 691                 /* Should we return something other than ENODEV here? */
 692                 return -ENODEV;
 693         }
 694
 695         /* Verify that we have a CS4270 */
 696
 697         ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);
 698         if (ret < 0) {
 699                 dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
 700                        i2c_client->addr);
 701                 return ret;
 702         }
 703         /* The top four bits of the chip ID should be 1100. */
 704         if ((ret & 0xF0) != 0xC0) {
 705                 dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
 706                        i2c_client->addr);
 707                 return -ENODEV;
 708         }
 709
 710         dev_info(&i2c_client->dev, "found device at i2c address %X\n",
 711                 i2c_client->addr);
 712         dev_info(&i2c_client->dev, "hardware revision %X\n", ret & 0xF);
 713
 714         /* Allocate enough space for the snd_soc_codec structure
 715            and our private data together. */
 716         cs4270 = kzalloc(sizeof(struct cs4270_private), GFP_KERNEL);
 717         if (!cs4270) {
 718                 dev_err(&i2c_client->dev, "could not allocate codec\n");
 719                 return -ENOMEM;
 720         }
 721         codec = &cs4270->codec;
 722
 723         mutex_init(&codec->mutex);
 724         INIT_LIST_HEAD(&codec->dapm_widgets);
 725         INIT_LIST_HEAD(&codec->dapm_paths);
 726
 727         codec->dev = &i2c_client->dev;
 728         codec->name = "CS4270";
 729         codec->owner = THIS_MODULE;
 730         codec->dai = &cs4270_dai;
 731         codec->num_dai = 1;
 732         codec->private_data = cs4270;
 733         codec->control_data = i2c_client;
 734         codec->read = cs4270_read_reg_cache;
 735         codec->write = cs4270_i2c_write;
 736         codec->reg_cache = cs4270->reg_cache;
 737         codec->reg_cache_size = CS4270_NUMREGS;
 738
 739         /* The I2C interface is set up, so pre-fill our register cache */
 740
 741         ret = cs4270_fill_cache(codec);
 742         if (ret < 0) {
 743                 dev_err(&i2c_client->dev, "failed to fill register cache\n");
 744                 goto error_free_codec;
 745         }
 746
 747         /* Disable auto-mute.  This feature appears to be buggy.  In some
 748          * situations, auto-mute will not deactivate when it should, so we want
 749          * this feature disabled by default.  An application (e.g. alsactl) can
 750          * re-enabled it by using the controls.
 751          */
 752
 753         reg = cs4270_read_reg_cache(codec, CS4270_MUTE);
 754         reg &= ~CS4270_MUTE_AUTO;
 755         ret = cs4270_i2c_write(codec, CS4270_MUTE, reg);
 756         if (ret < 0) {
 757                 dev_err(&i2c_client->dev, "i2c write failed\n");
 758                 return ret;
 759         }
 760
 761         /* Disable automatic volume control.  The hardware enables, and it
 762          * causes volume change commands to be delayed, sometimes until after
 763          * playback has started.  An application (e.g. alsactl) can
 764          * re-enabled it by using the controls.
 765          */
 766
 767         reg = cs4270_read_reg_cache(codec, CS4270_TRANS);
 768         reg &= ~(CS4270_TRANS_SOFT | CS4270_TRANS_ZERO);
 769         ret = cs4270_i2c_write(codec, CS4270_TRANS, reg);
 770         if (ret < 0) {
 771                 dev_err(&i2c_client->dev, "i2c write failed\n");
 772                 return ret;
 773         }
 774
 775         /* Initialize the DAI. Normally, we'd prefer to have a kmalloc'd DAI
 776          * structure for each CS4270 device, but the machine driver needs to
 777          * have a pointer to the DAI structure, so for now it must be a global
 778          * variable.
 779          */
 780         cs4270_dai.dev = &i2c_client->dev;
 781
 782         /* Register the DAI.  If all the other ASoC driver have already
 783          * registered, then this will call our probe function, so
 784          * cs4270_codec needs to be ready.
 785          */
 786         cs4270_codec = codec;
 787         ret = snd_soc_register_dai(&cs4270_dai);
 788         if (ret < 0) {
 789                 dev_err(&i2c_client->dev, "failed to register DAIe\n");
 790                 goto error_free_codec;
 791         }
 792
 793         i2c_set_clientdata(i2c_client, cs4270);
 794
 795         return 0;
 796
 797 error_free_codec:
 798         kfree(cs4270);
 799         cs4270_codec = NULL;
 800         cs4270_dai.dev = NULL;
 801
 802         return ret;
 803 }
 804
 805 /**
 806  * cs4270_i2c_remove - remove an I2C device
 807  * @i2c_client: the I2C client object
 808  *
 809  * This function is the counterpart to cs4270_i2c_probe().
 810  */
 811 static int cs4270_i2c_remove(struct i2c_client *i2c_client)
 812 {
 813         struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
 814
 815         kfree(cs4270);
 816         cs4270_codec = NULL;
 817         cs4270_dai.dev = NULL;
 818
 819         return 0;
 820 }
 821
 822 /*
 823  * cs4270_id - I2C device IDs supported by this driver
 824  */
 825 static struct i2c_device_id cs4270_id[] = {
 826         {"cs4270", 0},
 827         {}
 828 };
 829 MODULE_DEVICE_TABLE(i2c, cs4270_id);
 830
 831 #ifdef CONFIG_PM
 832
 833 /* This suspend/resume implementation can handle both - a simple standby
 834  * where the codec remains powered, and a full suspend, where the voltage
 835  * domain the codec is connected to is teared down and/or any other hardware
 836  * reset condition is asserted.
 837  *
 838  * The codec's own power saving features are enabled in the suspend callback,
 839  * and all registers are written back to the hardware when resuming.
 840  */
 841
 842 static int cs4270_soc_suspend(struct platform_device *pdev, pm_message_t mesg)
 843 {
 844         struct snd_soc_codec *codec = cs4270_codec;
 845         struct cs4270_private *cs4270 = codec->private_data;
 846         int reg, ret;
 847
 848         reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
 849         if (reg < 0)
 850                 return reg;
 851
 852         ret = snd_soc_write(codec, CS4270_PWRCTL, reg);
 853         if (ret < 0)
 854                 return ret;
 855
 856         regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
 857                                cs4270->supplies);
 858
 859         return 0;
 860 }
 861
 862 static int cs4270_soc_resume(struct platform_device *pdev)
 863 {
 864         struct snd_soc_codec *codec = cs4270_codec;
 865         struct cs4270_private *cs4270 = codec->private_data;
 866         struct i2c_client *i2c_client = codec->control_data;
 867         int reg;
 868
 869         regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 870                               cs4270->supplies);
 871
 872         /* In case the device was put to hard reset during sleep, we need to
 873          * wait 500ns here before any I2C communication. */
 874         ndelay(500);
 875
 876         /* first restore the entire register cache ... */
 877         for (reg = CS4270_FIRSTREG; reg <= CS4270_LASTREG; reg++) {
 878                 u8 val = snd_soc_read(codec, reg);
 879
 880                 if (i2c_smbus_write_byte_data(i2c_client, reg, val)) {
 881                         dev_err(codec->dev, "i2c write failed\n");
 882                         return -EIO;
 883                 }
 884         }
 885
 886         /* ... then disable the power-down bits */
 887         reg = snd_soc_read(codec, CS4270_PWRCTL);
 888         reg &= ~CS4270_PWRCTL_PDN_ALL;
 889
 890         return snd_soc_write(codec, CS4270_PWRCTL, reg);
 891 }
 892 #else
 893 #define cs4270_soc_suspend      NULL
 894 #define cs4270_soc_resume       NULL
 895 #endif /* CONFIG_PM */
 896
 897 /*
 898  * cs4270_i2c_driver - I2C device identification
 899  *
 900  * This structure tells the I2C subsystem how to identify and support a
 901  * given I2C device type.
 902  */
 903 static struct i2c_driver cs4270_i2c_driver = {
 904         .driver = {
 905                 .name = "cs4270",
 906                 .owner = THIS_MODULE,
 907         },
 908         .id_table = cs4270_id,
 909         .probe = cs4270_i2c_probe,
 910         .remove = cs4270_i2c_remove,
 911 };
 912
 913 /*
 914  * ASoC codec device structure
 915  *
 916  * Assign this variable to the codec_dev field of the machine driver's
 917  * snd_soc_device structure.
 918  */
 919 struct snd_soc_codec_device soc_codec_device_cs4270 = {
 920         .probe =        cs4270_probe,
 921         .remove =       cs4270_remove,
 922         .suspend =      cs4270_soc_suspend,
 923         .resume =       cs4270_soc_resume,
 924 };
 925 EXPORT_SYMBOL_GPL(soc_codec_device_cs4270);
 926
 927 static int __init cs4270_init(void)
 928 {
 929         pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
 930
 931         return i2c_add_driver(&cs4270_i2c_driver);
 932 }
 933 module_init(cs4270_init);
 934
 935 static void __exit cs4270_exit(void)
 936 {
 937         i2c_del_driver(&cs4270_i2c_driver);
 938 }
 939 module_exit(cs4270_exit);
 940
 941 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
 942 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
 943 MODULE_LICENSE("GPL");