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