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 <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>
  33
  34 #include "cs4270.h"
  35
  36 /*
  37  * The codec isn't really big-endian or little-endian, since the I2S
  38  * interface requires data to be sent serially with the MSbit first.
  39  * However, to support BE and LE I2S devices, we specify both here.  That
  40  * way, ALSA will always match the bit patterns.
  41  */
  42 #define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8      | \
  43                         SNDRV_PCM_FMTBIT_S16_LE  | SNDRV_PCM_FMTBIT_S16_BE  | \
  44                         SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S18_3BE | \
  45                         SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S20_3BE | \
  46                         SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | \
  47                         SNDRV_PCM_FMTBIT_S24_LE  | SNDRV_PCM_FMTBIT_S24_BE)
  48
  49 /* CS4270 registers addresses */
  50 #define CS4270_CHIPID   0x01    /* Chip ID */
  51 #define CS4270_PWRCTL   0x02    /* Power Control */
  52 #define CS4270_MODE     0x03    /* Mode Control */
  53 #define CS4270_FORMAT   0x04    /* Serial Format, ADC/DAC Control */
  54 #define CS4270_TRANS    0x05    /* Transition Control */
  55 #define CS4270_MUTE     0x06    /* Mute Control */
  56 #define CS4270_VOLA     0x07    /* DAC Channel A Volume Control */
  57 #define CS4270_VOLB     0x08    /* DAC Channel B Volume Control */
  58
  59 #define CS4270_FIRSTREG 0x01
  60 #define CS4270_LASTREG  0x08
  61 #define CS4270_NUMREGS  (CS4270_LASTREG - CS4270_FIRSTREG + 1)
  62 #define CS4270_I2C_INCR 0x80
  63
  64 /* Bit masks for the CS4270 registers */
  65 #define CS4270_CHIPID_ID        0xF0
  66 #define CS4270_CHIPID_REV       0x0F
  67 #define CS4270_PWRCTL_FREEZE    0x80
  68 #define CS4270_PWRCTL_PDN_ADC   0x20
  69 #define CS4270_PWRCTL_PDN_DAC   0x02
  70 #define CS4270_PWRCTL_PDN       0x01
  71 #define CS4270_PWRCTL_PDN_ALL   \
  72         (CS4270_PWRCTL_PDN_ADC | CS4270_PWRCTL_PDN_DAC | CS4270_PWRCTL_PDN)
  73 #define CS4270_MODE_SPEED_MASK  0x30
  74 #define CS4270_MODE_1X          0x00
  75 #define CS4270_MODE_2X          0x10
  76 #define CS4270_MODE_4X          0x20
  77 #define CS4270_MODE_SLAVE       0x30
  78 #define CS4270_MODE_DIV_MASK    0x0E
  79 #define CS4270_MODE_DIV1        0x00
  80 #define CS4270_MODE_DIV15       0x02
  81 #define CS4270_MODE_DIV2        0x04
  82 #define CS4270_MODE_DIV3        0x06
  83 #define CS4270_MODE_DIV4        0x08
  84 #define CS4270_MODE_POPGUARD    0x01
  85 #define CS4270_FORMAT_FREEZE_A  0x80
  86 #define CS4270_FORMAT_FREEZE_B  0x40
  87 #define CS4270_FORMAT_LOOPBACK  0x20
  88 #define CS4270_FORMAT_DAC_MASK  0x18
  89 #define CS4270_FORMAT_DAC_LJ    0x00
  90 #define CS4270_FORMAT_DAC_I2S   0x08
  91 #define CS4270_FORMAT_DAC_RJ16  0x18
  92 #define CS4270_FORMAT_DAC_RJ24  0x10
  93 #define CS4270_FORMAT_ADC_MASK  0x01
  94 #define CS4270_FORMAT_ADC_LJ    0x00
  95 #define CS4270_FORMAT_ADC_I2S   0x01
  96 #define CS4270_TRANS_ONE_VOL    0x80
  97 #define CS4270_TRANS_SOFT       0x40
  98 #define CS4270_TRANS_ZERO       0x20
  99 #define CS4270_TRANS_INV_ADC_A  0x08
 100 #define CS4270_TRANS_INV_ADC_B  0x10
 101 #define CS4270_TRANS_INV_DAC_A  0x02
 102 #define CS4270_TRANS_INV_DAC_B  0x04
 103 #define CS4270_TRANS_DEEMPH     0x01
 104 #define CS4270_MUTE_AUTO        0x20
 105 #define CS4270_MUTE_ADC_A       0x08
 106 #define CS4270_MUTE_ADC_B       0x10
 107 #define CS4270_MUTE_POLARITY    0x04
 108 #define CS4270_MUTE_DAC_A       0x01
 109 #define CS4270_MUTE_DAC_B       0x02
 110
 111 static const char *supply_names[] = {
 112         "va", "vd", "vlc"
 113 };
 114
 115 /* Private data for the CS4270 */
 116 struct cs4270_private {
 117         struct snd_soc_codec codec;
 118         u8 reg_cache[CS4270_NUMREGS];
 119         unsigned int mclk; /* Input frequency of the MCLK pin */
 120         unsigned int mode; /* The mode (I2S or left-justified) */
 121         unsigned int slave_mode;
 122         unsigned int manual_mute;
 123
 124         /* power domain regulators */
 125         struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
 126 };
 127
 128 /**
 129  * struct cs4270_mode_ratios - clock ratio tables
 130  * @ratio: the ratio of MCLK to the sample rate
 131  * @speed_mode: the Speed Mode bits to set in the Mode Control register for
 132  *              this ratio
 133  * @mclk: the Ratio Select bits to set in the Mode Control register for this
 134  *        ratio
 135  *
 136  * The data for this chart is taken from Table 5 of the CS4270 reference
 137  * manual.
 138  *
 139  * This table is used to determine how to program the Mode Control register.
 140  * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
 141  * rates the CS4270 currently supports.
 142  *
 143  * @speed_mode is the corresponding bit pattern to be written to the
 144  * MODE bits of the Mode Control Register
 145  *
 146  * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
 147  * the Mode Control Register.
 148  *
 149  * In situations where a single ratio is represented by multiple speed
 150  * modes, we favor the slowest speed.  E.g, for a ratio of 128, we pick
 151  * double-speed instead of quad-speed.  However, the CS4270 errata states
 152  * that divide-By-1.5 can cause failures, so we avoid that mode where
 153  * possible.
 154  *
 155  * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
 156  * work if Vd is 3.3V.  If this effects you, select the
 157  * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
 158  * never select any sample rates that require divide-by-1.5.
 159  */
 160 struct cs4270_mode_ratios {
 161         unsigned int ratio;
 162         u8 speed_mode;
 163         u8 mclk;
 164 };
 165
 166 static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
 167         {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
 168 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
 169         {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
 170 #endif
 171         {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
 172         {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
 173         {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
 174         {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
 175         {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
 176         {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
 177         {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
 178 };
 179
 180 /* The number of MCLK/LRCK ratios supported by the CS4270 */
 181 #define NUM_MCLK_RATIOS         ARRAY_SIZE(cs4270_mode_ratios)
 182
 183 /**
 184  * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
 185  * @codec_dai: the codec DAI
 186  * @clk_id: the clock ID (ignored)
 187  * @freq: the MCLK input frequency
 188  * @dir: the clock direction (ignored)
 189  *
 190  * This function is used to tell the codec driver what the input MCLK
 191  * frequency is.
 192  *
 193  * The value of MCLK is used to determine which sample rates are supported
 194  * by the CS4270.  The ratio of MCLK / Fs must be equal to one of nine
 195  * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
 196  *
 197  * This function calculates the nine ratios and determines which ones match
 198  * a standard sample rate.  If there's a match, then it is added to the list
 199  * of supported sample rates.
 200  *
 201  * This function must be called by the machine driver's 'startup' function,
 202  * otherwise the list of supported sample rates will not be available in
 203  * time for ALSA.
 204  *
 205  * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
 206  * theoretically possible sample rates to be enabled. Call it again with a
 207  * proper value set one the external clock is set (most probably you would do
 208  * that from a machine's driver 'hw_param' hook.
 209  */
 210 static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 211                                  int clk_id, unsigned int freq, int dir)
 212 {
 213         struct snd_soc_codec *codec = codec_dai->codec;
 214         struct cs4270_private *cs4270 = codec->private_data;
 215         unsigned int rates = 0;
 216         unsigned int rate_min = -1;
 217         unsigned int rate_max = 0;
 218         unsigned int i;
 219
 220         cs4270->mclk = freq;
 221
 222         if (cs4270->mclk) {
 223                 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
 224                         unsigned int rate = freq / cs4270_mode_ratios[i].ratio;
 225                         rates |= snd_pcm_rate_to_rate_bit(rate);
 226                         if (rate < rate_min)
 227                                 rate_min = rate;
 228                         if (rate > rate_max)
 229                                 rate_max = rate;
 230                 }
 231                 /* FIXME: soc should support a rate list */
 232                 rates &= ~SNDRV_PCM_RATE_KNOT;
 233
 234                 if (!rates) {
 235                         dev_err(codec->dev, "could not find a valid sample rate\n");
 236                         return -EINVAL;
 237                 }
 238         } else {
 239                 /* enable all possible rates */
 240                 rates = SNDRV_PCM_RATE_8000_192000;
 241                 rate_min = 8000;
 242                 rate_max = 192000;
 243         }
 244
 245         codec_dai->playback.rates = rates;
 246         codec_dai->playback.rate_min = rate_min;
 247         codec_dai->playback.rate_max = rate_max;
 248
 249         codec_dai->capture.rates = rates;
 250         codec_dai->capture.rate_min = rate_min;
 251         codec_dai->capture.rate_max = rate_max;
 252
 253         return 0;
 254 }
 255
 256 /**
 257  * cs4270_set_dai_fmt - configure the codec for the selected audio format
 258  * @codec_dai: the codec DAI
 259  * @format: a SND_SOC_DAIFMT_x value indicating the data format
 260  *
 261  * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
 262  * codec accordingly.
 263  *
 264  * Currently, this function only supports SND_SOC_DAIFMT_I2S and
 265  * SND_SOC_DAIFMT_LEFT_J.  The CS4270 codec also supports right-justified
 266  * data for playback only, but ASoC currently does not support different
 267  * formats for playback vs. record.
 268  */
 269 static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
 270                               unsigned int format)
 271 {
 272         struct snd_soc_codec *codec = codec_dai->codec;
 273         struct cs4270_private *cs4270 = codec->private_data;
 274         int ret = 0;
 275
 276         /* set DAI format */
 277         switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
 278         case SND_SOC_DAIFMT_I2S:
 279         case SND_SOC_DAIFMT_LEFT_J:
 280                 cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
 281                 break;
 282         default:
 283                 dev_err(codec->dev, "invalid dai format\n");
 284                 ret = -EINVAL;
 285         }
 286
 287         /* set master/slave audio interface */
 288         switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
 289         case SND_SOC_DAIFMT_CBS_CFS:
 290                 cs4270->slave_mode = 1;
 291                 break;
 292         case SND_SOC_DAIFMT_CBM_CFM:
 293                 cs4270->slave_mode = 0;
 294                 break;
 295         default:
 296                 /* all other modes are unsupported by the hardware */
 297                 ret = -EINVAL;
 298         }
 299
 300         return ret;
 301 }
 302
 303 /**
 304  * cs4270_fill_cache - pre-fill the CS4270 register cache.
 305  * @codec: the codec for this CS4270
 306  *
 307  * This function fills in the CS4270 register cache by reading the register
 308  * values from the hardware.
 309  *
 310  * This CS4270 registers are cached to avoid excessive I2C I/O operations.
 311  * After the initial read to pre-fill the cache, the CS4270 never updates
 312  * the register values, so we won't have a cache coherency problem.
 313  *
 314  * We use the auto-increment feature of the CS4270 to read all registers in
 315  * one shot.
 316  */
 317 static int cs4270_fill_cache(struct snd_soc_codec *codec)
 318 {
 319         u8 *cache = codec->reg_cache;
 320         struct i2c_client *i2c_client = codec->control_data;
 321         s32 length;
 322
 323         length = i2c_smbus_read_i2c_block_data(i2c_client,
 324                 CS4270_FIRSTREG | CS4270_I2C_INCR, CS4270_NUMREGS, cache);
 325
 326         if (length != CS4270_NUMREGS) {
 327                 dev_err(codec->dev, "i2c read failure, addr=0x%x\n",
 328                        i2c_client->addr);
 329                 return -EIO;
 330         }
 331
 332         return 0;
 333 }
 334
 335 /**
 336  * cs4270_read_reg_cache - read from the CS4270 register cache.
 337  * @codec: the codec for this CS4270
 338  * @reg: the register to read
 339  *
 340  * This function returns the value for a given register.  It reads only from
 341  * the register cache, not the hardware itself.
 342  *
 343  * This CS4270 registers are cached to avoid excessive I2C I/O operations.
 344  * After the initial read to pre-fill the cache, the CS4270 never updates
 345  * the register values, so we won't have a cache coherency problem.
 346  */
 347 static unsigned int cs4270_read_reg_cache(struct snd_soc_codec *codec,
 348         unsigned int reg)
 349 {
 350         u8 *cache = codec->reg_cache;
 351
 352         if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
 353                 return -EIO;
 354
 355         return cache[reg - CS4270_FIRSTREG];
 356 }
 357
 358 /**
 359  * cs4270_i2c_write - write to a CS4270 register via the I2C bus.
 360  * @codec: the codec for this CS4270
 361  * @reg: the register to write
 362  * @value: the value to write to the register
 363  *
 364  * This function writes the given value to the given CS4270 register, and
 365  * also updates the register cache.
 366  *
 367  * Note that we don't use the hw_write function pointer of snd_soc_codec.
 368  * That's because it's too clunky: the hw_write_t prototype does not match
 369  * i2c_smbus_write_byte_data(), and it's just another layer of overhead.
 370  */
 371 static int cs4270_i2c_write(struct snd_soc_codec *codec, unsigned int reg,
 372                             unsigned int value)
 373 {
 374         u8 *cache = codec->reg_cache;
 375
 376         if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
 377                 return -EIO;
 378
 379         /* Only perform an I2C operation if the new value is different */
 380         if (cache[reg - CS4270_FIRSTREG] != value) {
 381                 struct i2c_client *client = codec->control_data;
 382                 if (i2c_smbus_write_byte_data(client, reg, value)) {
 383                         dev_err(codec->dev, "i2c write failed\n");
 384                         return -EIO;
 385                 }
 386
 387                 /* We've written to the hardware, so update the cache */
 388                 cache[reg - CS4270_FIRSTREG] = value;
 389         }
 390
 391         return 0;
 392 }
 393
 394 /**
 395  * cs4270_hw_params - program the CS4270 with the given hardware parameters.
 396  * @substream: the audio stream
 397  * @params: the hardware parameters to set
 398  * @dai: the SOC DAI (ignored)
 399  *
 400  * This function programs the hardware with the values provided.
 401  * Specifically, the sample rate and the data format.
 402  *
 403  * The .ops functions are used to provide board-specific data, like input
 404  * frequencies, to this driver.  This function takes that information,
 405  * combines it with the hardware parameters provided, and programs the
 406  * hardware accordingly.
 407  */
 408 static int cs4270_hw_params(struct snd_pcm_substream *substream,
 409                             struct snd_pcm_hw_params *params,
 410                             struct snd_soc_dai *dai)
 411 {
 412         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 413         struct snd_soc_device *socdev = rtd->socdev;
 414         struct snd_soc_codec *codec = socdev->card->codec;
 415         struct cs4270_private *cs4270 = codec->private_data;
 416         int ret;
 417         unsigned int i;
 418         unsigned int rate;
 419         unsigned int ratio;
 420         int reg;
 421
 422         /* Figure out which MCLK/LRCK ratio to use */
 423
 424         rate = params_rate(params);     /* Sampling rate, in Hz */
 425         ratio = cs4270->mclk / rate;    /* MCLK/LRCK ratio */
 426
 427         for (i = 0; i < NUM_MCLK_RATIOS; i++) {
 428                 if (cs4270_mode_ratios[i].ratio == ratio)
 429                         break;
 430         }
 431
 432         if (i == NUM_MCLK_RATIOS) {
 433                 /* We did not find a matching ratio */
 434                 dev_err(codec->dev, "could not find matching ratio\n");
 435                 return -EINVAL;
 436         }
 437
 438         /* Set the sample rate */
 439
 440         reg = snd_soc_read(codec, CS4270_MODE);
 441         reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
 442         reg |= cs4270_mode_ratios[i].mclk;
 443
 444         if (cs4270->slave_mode)
 445                 reg |= CS4270_MODE_SLAVE;
 446         else
 447                 reg |= cs4270_mode_ratios[i].speed_mode;
 448
 449         ret = snd_soc_write(codec, CS4270_MODE, reg);
 450         if (ret < 0) {
 451                 dev_err(codec->dev, "i2c write failed\n");
 452                 return ret;
 453         }
 454
 455         /* Set the DAI format */
 456
 457         reg = snd_soc_read(codec, CS4270_FORMAT);
 458         reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
 459
 460         switch (cs4270->mode) {
 461         case SND_SOC_DAIFMT_I2S:
 462                 reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
 463                 break;
 464         case SND_SOC_DAIFMT_LEFT_J:
 465                 reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
 466                 break;
 467         default:
 468                 dev_err(codec->dev, "unknown dai format\n");
 469                 return -EINVAL;
 470         }
 471
 472         ret = snd_soc_write(codec, CS4270_FORMAT, reg);
 473         if (ret < 0) {
 474                 dev_err(codec->dev, "i2c write failed\n");
 475                 return ret;
 476         }
 477
 478         return ret;
 479 }
 480
 481 /**
 482  * cs4270_dai_mute - enable/disable the CS4270 external mute
 483  * @dai: the SOC DAI
 484  * @mute: 0 = disable mute, 1 = enable mute
 485  *
 486  * This function toggles the mute bits in the MUTE register.  The CS4270's
 487  * mute capability is intended for external muting circuitry, so if the
 488  * board does not have the MUTEA or MUTEB pins connected to such circuitry,
 489  * then this function will do nothing.
 490  */
 491 static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
 492 {
 493         struct snd_soc_codec *codec = dai->codec;
 494         struct cs4270_private *cs4270 = codec->private_data;
 495         int reg6;
 496
 497         reg6 = snd_soc_read(codec, CS4270_MUTE);
 498
 499         if (mute)
 500                 reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
 501         else {
 502                 reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
 503                 reg6 |= cs4270->manual_mute;
 504         }
 505
 506         return snd_soc_write(codec, CS4270_MUTE, reg6);
 507 }
 508
 509 /**
 510  * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
 511  *                       alsa control.
 512  * @kcontrol: mixer control
 513  * @ucontrol: control element information
 514  *
 515  * This function basically passes the arguments on to the generic
 516  * snd_soc_put_volsw() function and saves the mute information in
 517  * our private data structure. This is because we want to prevent
 518  * cs4270_dai_mute() neglecting the user's decision to manually
 519  * mute the codec's output.
 520  *
 521  * Returns 0 for success.
 522  */
 523 static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
 524                                 struct snd_ctl_elem_value *ucontrol)
 525 {
 526         struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
 527         struct cs4270_private *cs4270 = codec->private_data;
 528         int left = !ucontrol->value.integer.value[0];
 529         int right = !ucontrol->value.integer.value[1];
 530
 531         cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
 532                               (right ? CS4270_MUTE_DAC_B : 0);
 533
 534         return snd_soc_put_volsw(kcontrol, ucontrol);
 535 }
 536
 537 /* A list of non-DAPM controls that the CS4270 supports */
 538 static const struct snd_kcontrol_new cs4270_snd_controls[] = {
 539         SOC_DOUBLE_R("Master Playback Volume",
 540                 CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
 541         SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
 542         SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
 543         SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
 544         SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
 545         SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
 546         SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
 547         SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
 548         SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
 549                 snd_soc_get_volsw, cs4270_soc_put_mute),
 550 };
 551
 552 /*
 553  * cs4270_codec - global variable to store codec for the ASoC probe function
 554  *
 555  * If struct i2c_driver had a private_data field, we wouldn't need to use
 556  * cs4270_codec.  This is the only way to pass the codec structure from
 557  * cs4270_i2c_probe() to cs4270_probe().  Unfortunately, there is no good
 558  * way to synchronize these two functions.  cs4270_i2c_probe() can be called
 559  * multiple times before cs4270_probe() is called even once.  So for now, we
 560  * also only allow cs4270_i2c_probe() to be run once.  That means that we do
 561  * not support more than one cs4270 device in the system, at least for now.
 562  */
 563 static struct snd_soc_codec *cs4270_codec;
 564
 565 static struct snd_soc_dai_ops cs4270_dai_ops = {
 566         .hw_params      = cs4270_hw_params,
 567         .set_sysclk     = cs4270_set_dai_sysclk,
 568         .set_fmt        = cs4270_set_dai_fmt,
 569         .digital_mute   = cs4270_dai_mute,
 570 };
 571
 572 struct snd_soc_dai cs4270_dai = {
 573         .name = "cs4270",
 574         .playback = {
 575                 .stream_name = "Playback",
 576                 .channels_min = 1,
 577                 .channels_max = 2,
 578                 .rates = 0,
 579                 .formats = CS4270_FORMATS,
 580         },
 581         .capture = {
 582                 .stream_name = "Capture",
 583                 .channels_min = 1,
 584                 .channels_max = 2,
 585                 .rates = 0,
 586                 .formats = CS4270_FORMATS,
 587         },
 588         .ops = &cs4270_dai_ops,
 589 };
 590 EXPORT_SYMBOL_GPL(cs4270_dai);
 591
 592 /**
 593  * cs4270_probe - ASoC probe function
 594  * @pdev: platform device
 595  *
 596  * This function is called when ASoC has all the pieces it needs to
 597  * instantiate a sound driver.
 598  */
 599 static int cs4270_probe(struct platform_device *pdev)
 600 {
 601         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 602         struct snd_soc_codec *codec = cs4270_codec;
 603         struct cs4270_private *cs4270 = codec->private_data;
 604         int i, ret;
 605
 606         /* Connect the codec to the socdev.  snd_soc_new_pcms() needs this. */
 607         socdev->card->codec = codec;
 608
 609         /* Register PCMs */
 610         ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
 611         if (ret < 0) {
 612                 dev_err(codec->dev, "failed to create pcms\n");
 613                 return ret;
 614         }
 615
 616         /* Add the non-DAPM controls */
 617         ret = snd_soc_add_controls(codec, cs4270_snd_controls,
 618                                 ARRAY_SIZE(cs4270_snd_controls));
 619         if (ret < 0) {
 620                 dev_err(codec->dev, "failed to add controls\n");
 621                 goto error_free_pcms;
 622         }
 623
 624         /* get the power supply regulators */
 625         for (i = 0; i < ARRAY_SIZE(supply_names); i++)
 626                 cs4270->supplies[i].supply = supply_names[i];
 627
 628         ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(cs4270->supplies),
 629                                  cs4270->supplies);
 630         if (ret < 0)
 631                 goto error_free_pcms;
 632
 633         ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 634                                     cs4270->supplies);
 635         if (ret < 0)
 636                 goto error_free_regulators;
 637
 638         return 0;
 639
 640 error_free_regulators:
 641         regulator_bulk_free(ARRAY_SIZE(cs4270->supplies),
 642                             cs4270->supplies);
 643
 644 error_free_pcms:
 645         snd_soc_free_pcms(socdev);
 646
 647         return ret;
 648 }
 649
 650 /**
 651  * cs4270_remove - ASoC remove function
 652  * @pdev: platform device
 653  *
 654  * This function is the counterpart to cs4270_probe().
 655  */
 656 static int cs4270_remove(struct platform_device *pdev)
 657 {
 658         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 659         struct snd_soc_codec *codec = cs4270_codec;
 660         struct cs4270_private *cs4270 = codec->private_data;
 661
 662         snd_soc_free_pcms(socdev);
 663         regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
 664         regulator_bulk_free(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
 665
 666         return 0;
 667 };
 668
 669 /**
 670  * cs4270_i2c_probe - initialize the I2C interface of the CS4270
 671  * @i2c_client: the I2C client object
 672  * @id: the I2C device ID (ignored)
 673  *
 674  * This function is called whenever the I2C subsystem finds a device that
 675  * matches the device ID given via a prior call to i2c_add_driver().
 676  */
 677 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
 678         const struct i2c_device_id *id)
 679 {
 680         struct snd_soc_codec *codec;
 681         struct cs4270_private *cs4270;
 682         unsigned int reg;
 683         int ret;
 684
 685         /* For now, we only support one cs4270 device in the system.  See the
 686          * comment for cs4270_codec.
 687          */
 688         if (cs4270_codec) {
 689                 dev_err(&i2c_client->dev, "ignoring CS4270 at addr %X\n",
 690                        i2c_client->addr);
 691                 dev_err(&i2c_client->dev, "only one per board allowed\n");
 692                 /* Should we return something other than ENODEV here? */
 693                 return -ENODEV;
 694         }
 695
 696         /* Verify that we have a CS4270 */
 697
 698         ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);
 699         if (ret < 0) {
 700                 dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
 701                        i2c_client->addr);
 702                 return ret;
 703         }
 704         /* The top four bits of the chip ID should be 1100. */
 705         if ((ret & 0xF0) != 0xC0) {
 706                 dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
 707                        i2c_client->addr);
 708                 return -ENODEV;
 709         }
 710
 711         dev_info(&i2c_client->dev, "found device at i2c address %X\n",
 712                 i2c_client->addr);
 713         dev_info(&i2c_client->dev, "hardware revision %X\n", ret & 0xF);
 714
 715         /* Allocate enough space for the snd_soc_codec structure
 716            and our private data together. */
 717         cs4270 = kzalloc(sizeof(struct cs4270_private), GFP_KERNEL);
 718         if (!cs4270) {
 719                 dev_err(&i2c_client->dev, "could not allocate codec\n");
 720                 return -ENOMEM;
 721         }
 722         codec = &cs4270->codec;
 723
 724         mutex_init(&codec->mutex);
 725         INIT_LIST_HEAD(&codec->dapm_widgets);
 726         INIT_LIST_HEAD(&codec->dapm_paths);
 727
 728         codec->dev = &i2c_client->dev;
 729         codec->name = "CS4270";
 730         codec->owner = THIS_MODULE;
 731         codec->dai = &cs4270_dai;
 732         codec->num_dai = 1;
 733         codec->private_data = cs4270;
 734         codec->control_data = i2c_client;
 735         codec->read = cs4270_read_reg_cache;
 736         codec->write = cs4270_i2c_write;
 737         codec->reg_cache = cs4270->reg_cache;
 738         codec->reg_cache_size = CS4270_NUMREGS;
 739
 740         /* The I2C interface is set up, so pre-fill our register cache */
 741
 742         ret = cs4270_fill_cache(codec);
 743         if (ret < 0) {
 744                 dev_err(&i2c_client->dev, "failed to fill register cache\n");
 745                 goto error_free_codec;
 746         }
 747
 748         /* Disable auto-mute.  This feature appears to be buggy.  In some
 749          * situations, auto-mute will not deactivate when it should, so we want
 750          * this feature disabled by default.  An application (e.g. alsactl) can
 751          * re-enabled it by using the controls.
 752          */
 753
 754         reg = cs4270_read_reg_cache(codec, CS4270_MUTE);
 755         reg &= ~CS4270_MUTE_AUTO;
 756         ret = cs4270_i2c_write(codec, CS4270_MUTE, reg);
 757         if (ret < 0) {
 758                 dev_err(&i2c_client->dev, "i2c write failed\n");
 759                 return ret;
 760         }
 761
 762         /* Disable automatic volume control.  The hardware enables, and it
 763          * causes volume change commands to be delayed, sometimes until after
 764          * playback has started.  An application (e.g. alsactl) can
 765          * re-enabled it by using the controls.
 766          */
 767
 768         reg = cs4270_read_reg_cache(codec, CS4270_TRANS);
 769         reg &= ~(CS4270_TRANS_SOFT | CS4270_TRANS_ZERO);
 770         ret = cs4270_i2c_write(codec, CS4270_TRANS, reg);
 771         if (ret < 0) {
 772                 dev_err(&i2c_client->dev, "i2c write failed\n");
 773                 return ret;
 774         }
 775
 776         /* Initialize the DAI. Normally, we'd prefer to have a kmalloc'd DAI
 777          * structure for each CS4270 device, but the machine driver needs to
 778          * have a pointer to the DAI structure, so for now it must be a global
 779          * variable.
 780          */
 781         cs4270_dai.dev = &i2c_client->dev;
 782
 783         /* Register the DAI.  If all the other ASoC driver have already
 784          * registered, then this will call our probe function, so
 785          * cs4270_codec needs to be ready.
 786          */
 787         cs4270_codec = codec;
 788         ret = snd_soc_register_dai(&cs4270_dai);
 789         if (ret < 0) {
 790                 dev_err(&i2c_client->dev, "failed to register DAIe\n");
 791                 goto error_free_codec;
 792         }
 793
 794         i2c_set_clientdata(i2c_client, cs4270);
 795
 796         return 0;
 797
 798 error_free_codec:
 799         kfree(cs4270);
 800         cs4270_codec = NULL;
 801         cs4270_dai.dev = NULL;
 802
 803         return ret;
 804 }
 805
 806 /**
 807  * cs4270_i2c_remove - remove an I2C device
 808  * @i2c_client: the I2C client object
 809  *
 810  * This function is the counterpart to cs4270_i2c_probe().
 811  */
 812 static int cs4270_i2c_remove(struct i2c_client *i2c_client)
 813 {
 814         struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
 815
 816         kfree(cs4270);
 817         cs4270_codec = NULL;
 818         cs4270_dai.dev = NULL;
 819
 820         return 0;
 821 }
 822
 823 /*
 824  * cs4270_id - I2C device IDs supported by this driver
 825  */
 826 static struct i2c_device_id cs4270_id[] = {
 827         {"cs4270", 0},
 828         {}
 829 };
 830 MODULE_DEVICE_TABLE(i2c, cs4270_id);
 831
 832 #ifdef CONFIG_PM
 833
 834 /* This suspend/resume implementation can handle both - a simple standby
 835  * where the codec remains powered, and a full suspend, where the voltage
 836  * domain the codec is connected to is teared down and/or any other hardware
 837  * reset condition is asserted.
 838  *
 839  * The codec's own power saving features are enabled in the suspend callback,
 840  * and all registers are written back to the hardware when resuming.
 841  */
 842
 843 static int cs4270_soc_suspend(struct platform_device *pdev, pm_message_t mesg)
 844 {
 845         struct snd_soc_codec *codec = cs4270_codec;
 846         struct cs4270_private *cs4270 = codec->private_data;
 847         int reg, ret;
 848
 849         reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
 850         if (reg < 0)
 851                 return reg;
 852
 853         ret = snd_soc_write(codec, CS4270_PWRCTL, reg);
 854         if (ret < 0)
 855                 return ret;
 856
 857         regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
 858                                cs4270->supplies);
 859
 860         return 0;
 861 }
 862
 863 static int cs4270_soc_resume(struct platform_device *pdev)
 864 {
 865         struct snd_soc_codec *codec = cs4270_codec;
 866         struct cs4270_private *cs4270 = codec->private_data;
 867         struct i2c_client *i2c_client = codec->control_data;
 868         int reg;
 869
 870         regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
 871                               cs4270->supplies);
 872
 873         /* In case the device was put to hard reset during sleep, we need to
 874          * wait 500ns here before any I2C communication. */
 875         ndelay(500);
 876
 877         /* first restore the entire register cache ... */
 878         for (reg = CS4270_FIRSTREG; reg <= CS4270_LASTREG; reg++) {
 879                 u8 val = snd_soc_read(codec, reg);
 880
 881                 if (i2c_smbus_write_byte_data(i2c_client, reg, val)) {
 882                         dev_err(codec->dev, "i2c write failed\n");
 883                         return -EIO;
 884                 }
 885         }
 886
 887         /* ... then disable the power-down bits */
 888         reg = snd_soc_read(codec, CS4270_PWRCTL);
 889         reg &= ~CS4270_PWRCTL_PDN_ALL;
 890
 891         return snd_soc_write(codec, CS4270_PWRCTL, reg);
 892 }
 893 #else
 894 #define cs4270_soc_suspend      NULL
 895 #define cs4270_soc_resume       NULL
 896 #endif /* CONFIG_PM */
 897
 898 /*
 899  * cs4270_i2c_driver - I2C device identification
 900  *
 901  * This structure tells the I2C subsystem how to identify and support a
 902  * given I2C device type.
 903  */
 904 static struct i2c_driver cs4270_i2c_driver = {
 905         .driver = {
 906                 .name = "cs4270",
 907                 .owner = THIS_MODULE,
 908         },
 909         .id_table = cs4270_id,
 910         .probe = cs4270_i2c_probe,
 911         .remove = cs4270_i2c_remove,
 912 };
 913
 914 /*
 915  * ASoC codec device structure
 916  *
 917  * Assign this variable to the codec_dev field of the machine driver's
 918  * snd_soc_device structure.
 919  */
 920 struct snd_soc_codec_device soc_codec_device_cs4270 = {
 921         .probe =        cs4270_probe,
 922         .remove =       cs4270_remove,
 923         .suspend =      cs4270_soc_suspend,
 924         .resume =       cs4270_soc_resume,
 925 };
 926 EXPORT_SYMBOL_GPL(soc_codec_device_cs4270);
 927
 928 static int __init cs4270_init(void)
 929 {
 930         pr_info("Cirrus Logic CS4270 ALSA SoC Codec Driver\n");
 931
 932         return i2c_add_driver(&cs4270_i2c_driver);
 933 }
 934 module_init(cs4270_init);
 935
 936 static void __exit cs4270_exit(void)
 937 {
 938         i2c_del_driver(&cs4270_i2c_driver);
 939 }
 940 module_exit(cs4270_exit);
 941
 942 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
 943 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
 944 MODULE_LICENSE("GPL");