sound/soc/meson/aiu-encoder-i2s.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Copyright (c) 2020 BayLibre, SAS.
   4 // Author: Jerome Brunet <jbrunet@baylibre.com>
   5
   6 #include <linux/bitfield.h>
   7 #include <linux/clk.h>
   8 #include <sound/pcm_params.h>
   9 #include <sound/soc.h>
  10 #include <sound/soc-dai.h>
  11
  12 #include "aiu.h"
  13
  14 #define AIU_I2S_SOURCE_DESC_MODE_8CH    BIT(0)
  15 #define AIU_I2S_SOURCE_DESC_MODE_24BIT  BIT(5)
  16 #define AIU_I2S_SOURCE_DESC_MODE_32BIT  BIT(9)
  17 #define AIU_I2S_SOURCE_DESC_MODE_SPLIT  BIT(11)
  18 #define AIU_RST_SOFT_I2S_FAST           BIT(0)
  19
  20 #define AIU_I2S_DAC_CFG_MSB_FIRST       BIT(2)
  21 #define AIU_I2S_MISC_HOLD_EN            BIT(2)
  22 #define AIU_CLK_CTRL_I2S_DIV_EN         BIT(0)
  23 #define AIU_CLK_CTRL_I2S_DIV            GENMASK(3, 2)
  24 #define AIU_CLK_CTRL_AOCLK_INVERT       BIT(6)
  25 #define AIU_CLK_CTRL_LRCLK_INVERT       BIT(7)
  26 #define AIU_CLK_CTRL_LRCLK_SKEW         GENMASK(9, 8)
  27 #define AIU_CLK_CTRL_MORE_HDMI_AMCLK    BIT(6)
  28 #define AIU_CLK_CTRL_MORE_I2S_DIV       GENMASK(5, 0)
  29 #define AIU_CODEC_DAC_LRCLK_CTRL_DIV    GENMASK(11, 0)
  30
  31 static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component,
  32                                            bool enable)
  33 {
  34         snd_soc_component_update_bits(component, AIU_CLK_CTRL,
  35                                       AIU_CLK_CTRL_I2S_DIV_EN,
  36                                       enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0);
  37 }
  38
  39 static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
  40                                  bool enable)
  41 {
  42         snd_soc_component_update_bits(component, AIU_I2S_MISC,
  43                                       AIU_I2S_MISC_HOLD_EN,
  44                                       enable ? AIU_I2S_MISC_HOLD_EN : 0);
  45 }
  46
  47 static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
  48                                    struct snd_soc_dai *dai)
  49 {
  50         struct snd_soc_component *component = dai->component;
  51
  52         switch (cmd) {
  53         case SNDRV_PCM_TRIGGER_START:
  54         case SNDRV_PCM_TRIGGER_RESUME:
  55         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
  56                 aiu_encoder_i2s_hold(component, false);
  57                 return 0;
  58
  59         case SNDRV_PCM_TRIGGER_STOP:
  60         case SNDRV_PCM_TRIGGER_SUSPEND:
  61         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
  62                 aiu_encoder_i2s_hold(component, true);
  63                 return 0;
  64
  65         default:
  66                 return -EINVAL;
  67         }
  68 }
  69
  70 static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component,
  71                                       struct snd_pcm_hw_params *params)
  72 {
  73         /* Always operate in split (classic interleaved) mode */
  74         unsigned int desc = AIU_I2S_SOURCE_DESC_MODE_SPLIT;
  75         unsigned int val;
  76
  77         /* Reset required to update the pipeline */
  78         snd_soc_component_write(component, AIU_RST_SOFT, AIU_RST_SOFT_I2S_FAST);
  79         snd_soc_component_read(component, AIU_I2S_SYNC, &val);
  80
  81         switch (params_physical_width(params)) {
  82         case 16: /* Nothing to do */
  83                 break;
  84
  85         case 32:
  86                 desc |= (AIU_I2S_SOURCE_DESC_MODE_24BIT |
  87                          AIU_I2S_SOURCE_DESC_MODE_32BIT);
  88                 break;
  89
  90         default:
  91                 return -EINVAL;
  92         }
  93
  94         switch (params_channels(params)) {
  95         case 2: /* Nothing to do */
  96                 break;
  97         case 8:
  98                 desc |= AIU_I2S_SOURCE_DESC_MODE_8CH;
  99                 break;
 100         default:
 101                 return -EINVAL;
 102         }
 103
 104         snd_soc_component_update_bits(component, AIU_I2S_SOURCE_DESC,
 105                                       AIU_I2S_SOURCE_DESC_MODE_8CH |
 106                                       AIU_I2S_SOURCE_DESC_MODE_24BIT |
 107                                       AIU_I2S_SOURCE_DESC_MODE_32BIT |
 108                                       AIU_I2S_SOURCE_DESC_MODE_SPLIT,
 109                                       desc);
 110
 111         return 0;
 112 }
 113
 114 static int aiu_encoder_i2s_set_clocks(struct snd_soc_component *component,
 115                                       struct snd_pcm_hw_params *params)
 116 {
 117         struct aiu *aiu = snd_soc_component_get_drvdata(component);
 118         unsigned int srate = params_rate(params);
 119         unsigned int fs, bs;
 120
 121         /* Get the oversampling factor */
 122         fs = DIV_ROUND_CLOSEST(clk_get_rate(aiu->i2s.clks[MCLK].clk), srate);
 123
 124         if (fs % 64)
 125                 return -EINVAL;
 126
 127         /* Send data MSB first */
 128         snd_soc_component_update_bits(component, AIU_I2S_DAC_CFG,
 129                                       AIU_I2S_DAC_CFG_MSB_FIRST,
 130                                       AIU_I2S_DAC_CFG_MSB_FIRST);
 131
 132         /* Set bclk to lrlck ratio */
 133         snd_soc_component_update_bits(component, AIU_CODEC_DAC_LRCLK_CTRL,
 134                                       AIU_CODEC_DAC_LRCLK_CTRL_DIV,
 135                                       FIELD_PREP(AIU_CODEC_DAC_LRCLK_CTRL_DIV,
 136                                                  64 - 1));
 137
 138         /* Use CLK_MORE for mclk to bclk divider */
 139         snd_soc_component_update_bits(component, AIU_CLK_CTRL,
 140                                       AIU_CLK_CTRL_I2S_DIV, 0);
 141
 142         /*
 143          * NOTE: this HW is odd.
 144          * In most configuration, the i2s divider is 'mclk / blck'.
 145          * However, in 16 bits - 8ch mode, this factor needs to be
 146          * increased by 50% to get the correct output rate.
 147          * No idea why !
 148          */
 149         bs = fs / 64;
 150         if (params_width(params) == 16 && params_channels(params) == 8) {
 151                 if (bs % 2) {
 152                         dev_err(component->dev,
 153                                 "Cannot increase i2s divider by 50%%\n");
 154                         return -EINVAL;
 155                 }
 156                 bs += bs / 2;
 157         }
 158
 159         snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
 160                                       AIU_CLK_CTRL_MORE_I2S_DIV,
 161                                       FIELD_PREP(AIU_CLK_CTRL_MORE_I2S_DIV,
 162                                                  bs - 1));
 163
 164         /* Make sure amclk is used for HDMI i2s as well */
 165         snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
 166                                       AIU_CLK_CTRL_MORE_HDMI_AMCLK,
 167                                       AIU_CLK_CTRL_MORE_HDMI_AMCLK);
 168
 169         return 0;
 170 }
 171
 172 static int aiu_encoder_i2s_hw_params(struct snd_pcm_substream *substream,
 173                                      struct snd_pcm_hw_params *params,
 174                                      struct snd_soc_dai *dai)
 175 {
 176         struct snd_soc_component *component = dai->component;
 177         int ret;
 178
 179         /* Disable the clock while changing the settings */
 180         aiu_encoder_i2s_divider_enable(component, false);
 181
 182         ret = aiu_encoder_i2s_setup_desc(component, params);
 183         if (ret) {
 184                 dev_err(dai->dev, "setting i2s desc failed\n");
 185                 return ret;
 186         }
 187
 188         ret = aiu_encoder_i2s_set_clocks(component, params);
 189         if (ret) {
 190                 dev_err(dai->dev, "setting i2s clocks failed\n");
 191                 return ret;
 192         }
 193
 194         aiu_encoder_i2s_divider_enable(component, true);
 195
 196         return 0;
 197 }
 198
 199 static int aiu_encoder_i2s_hw_free(struct snd_pcm_substream *substream,
 200                                    struct snd_soc_dai *dai)
 201 {
 202         struct snd_soc_component *component = dai->component;
 203
 204         aiu_encoder_i2s_divider_enable(component, false);
 205
 206         return 0;
 207 }
 208
 209 static int aiu_encoder_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
 210 {
 211         struct snd_soc_component *component = dai->component;
 212         unsigned int inv = fmt & SND_SOC_DAIFMT_INV_MASK;
 213         unsigned int val = 0;
 214         unsigned int skew;
 215
 216         /* Only CPU Master / Codec Slave supported ATM */
 217         if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS)
 218                 return -EINVAL;
 219
 220         if (inv == SND_SOC_DAIFMT_NB_IF ||
 221             inv == SND_SOC_DAIFMT_IB_IF)
 222                 val |= AIU_CLK_CTRL_LRCLK_INVERT;
 223
 224         if (inv == SND_SOC_DAIFMT_IB_NF ||
 225             inv == SND_SOC_DAIFMT_IB_IF)
 226                 val |= AIU_CLK_CTRL_AOCLK_INVERT;
 227
 228         /* Signal skew */
 229         switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 230         case SND_SOC_DAIFMT_I2S:
 231                 /* Invert sample clock for i2s */
 232                 val ^= AIU_CLK_CTRL_LRCLK_INVERT;
 233                 skew = 1;
 234                 break;
 235         case SND_SOC_DAIFMT_LEFT_J:
 236                 skew = 0;
 237                 break;
 238         default:
 239                 return -EINVAL;
 240         }
 241
 242         val |= FIELD_PREP(AIU_CLK_CTRL_LRCLK_SKEW, skew);
 243         snd_soc_component_update_bits(component, AIU_CLK_CTRL,
 244                                       AIU_CLK_CTRL_LRCLK_INVERT |
 245                                       AIU_CLK_CTRL_AOCLK_INVERT |
 246                                       AIU_CLK_CTRL_LRCLK_SKEW,
 247                                       val);
 248
 249         return 0;
 250 }
 251
 252 static int aiu_encoder_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
 253                                       unsigned int freq, int dir)
 254 {
 255         struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
 256         int ret;
 257
 258         if (WARN_ON(clk_id != 0))
 259                 return -EINVAL;
 260
 261         if (dir == SND_SOC_CLOCK_IN)
 262                 return 0;
 263
 264         ret = clk_set_rate(aiu->i2s.clks[MCLK].clk, freq);
 265         if (ret)
 266                 dev_err(dai->dev, "Failed to set sysclk to %uHz", freq);
 267
 268         return ret;
 269 }
 270
 271 static const unsigned int hw_channels[] = {2, 8};
 272 static const struct snd_pcm_hw_constraint_list hw_channel_constraints = {
 273         .list = hw_channels,
 274         .count = ARRAY_SIZE(hw_channels),
 275         .mask = 0,
 276 };
 277
 278 static int aiu_encoder_i2s_startup(struct snd_pcm_substream *substream,
 279                                    struct snd_soc_dai *dai)
 280 {
 281         struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
 282         int ret;
 283
 284         /* Make sure the encoder gets either 2 or 8 channels */
 285         ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
 286                                          SNDRV_PCM_HW_PARAM_CHANNELS,
 287                                          &hw_channel_constraints);
 288         if (ret) {
 289                 dev_err(dai->dev, "adding channels constraints failed\n");
 290                 return ret;
 291         }
 292
 293         ret = clk_bulk_prepare_enable(aiu->i2s.clk_num, aiu->i2s.clks);
 294         if (ret)
 295                 dev_err(dai->dev, "failed to enable i2s clocks\n");
 296
 297         return ret;
 298 }
 299
 300 static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream,
 301                                      struct snd_soc_dai *dai)
 302 {
 303         struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
 304
 305         clk_bulk_disable_unprepare(aiu->i2s.clk_num, aiu->i2s.clks);
 306 }
 307
 308 const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
 309         .trigger        = aiu_encoder_i2s_trigger,
 310         .hw_params      = aiu_encoder_i2s_hw_params,
 311         .hw_free        = aiu_encoder_i2s_hw_free,
 312         .set_fmt        = aiu_encoder_i2s_set_fmt,
 313         .set_sysclk     = aiu_encoder_i2s_set_sysclk,
 314         .startup        = aiu_encoder_i2s_startup,
 315         .shutdown       = aiu_encoder_i2s_shutdown,
 316 };
 317