sound/soc/adi/axi-i2s.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012-2013, Analog Devices Inc.
   4  * Author: Lars-Peter Clausen <lars@metafoo.de>
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/init.h>
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/of.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/regmap.h>
  14 #include <linux/slab.h>
  15
  16 #include <sound/core.h>
  17 #include <sound/pcm.h>
  18 #include <sound/pcm_params.h>
  19 #include <sound/soc.h>
  20 #include <sound/dmaengine_pcm.h>
  21
  22 #define AXI_I2S_REG_RESET       0x00
  23 #define AXI_I2S_REG_CTRL        0x04
  24 #define AXI_I2S_REG_CLK_CTRL    0x08
  25 #define AXI_I2S_REG_STATUS      0x10
  26
  27 #define AXI_I2S_REG_RX_FIFO     0x28
  28 #define AXI_I2S_REG_TX_FIFO     0x2C
  29
  30 #define AXI_I2S_RESET_GLOBAL    BIT(0)
  31 #define AXI_I2S_RESET_TX_FIFO   BIT(1)
  32 #define AXI_I2S_RESET_RX_FIFO   BIT(2)
  33
  34 #define AXI_I2S_CTRL_TX_EN      BIT(0)
  35 #define AXI_I2S_CTRL_RX_EN      BIT(1)
  36
  37 /* The frame size is configurable, but for now we always set it 64 bit */
  38 #define AXI_I2S_BITS_PER_FRAME 64
  39
  40 struct axi_i2s {
  41         struct regmap *regmap;
  42         struct clk *clk;
  43         struct clk *clk_ref;
  44
  45         bool   has_capture;
  46         bool   has_playback;
  47
  48         struct snd_soc_dai_driver dai_driver;
  49
  50         struct snd_dmaengine_dai_dma_data capture_dma_data;
  51         struct snd_dmaengine_dai_dma_data playback_dma_data;
  52
  53         struct snd_ratnum ratnum;
  54         struct snd_pcm_hw_constraint_ratnums rate_constraints;
  55 };
  56
  57 static int axi_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
  58         struct snd_soc_dai *dai)
  59 {
  60         struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
  61         unsigned int mask, val;
  62
  63         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
  64                 mask = AXI_I2S_CTRL_RX_EN;
  65         else
  66                 mask = AXI_I2S_CTRL_TX_EN;
  67
  68         switch (cmd) {
  69         case SNDRV_PCM_TRIGGER_START:
  70         case SNDRV_PCM_TRIGGER_RESUME:
  71         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
  72                 val = mask;
  73                 break;
  74         case SNDRV_PCM_TRIGGER_STOP:
  75         case SNDRV_PCM_TRIGGER_SUSPEND:
  76         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
  77                 val = 0;
  78                 break;
  79         default:
  80                 return -EINVAL;
  81         }
  82
  83         regmap_update_bits(i2s->regmap, AXI_I2S_REG_CTRL, mask, val);
  84
  85         return 0;
  86 }
  87
  88 static int axi_i2s_hw_params(struct snd_pcm_substream *substream,
  89         struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
  90 {
  91         struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
  92         unsigned int bclk_div, word_size;
  93         unsigned int bclk_rate;
  94
  95         bclk_rate = params_rate(params) * AXI_I2S_BITS_PER_FRAME;
  96
  97         word_size = AXI_I2S_BITS_PER_FRAME / 2 - 1;
  98         bclk_div = DIV_ROUND_UP(clk_get_rate(i2s->clk_ref), bclk_rate) / 2 - 1;
  99
 100         regmap_write(i2s->regmap, AXI_I2S_REG_CLK_CTRL, (word_size << 16) |
 101                 bclk_div);
 102
 103         return 0;
 104 }
 105
 106 static int axi_i2s_startup(struct snd_pcm_substream *substream,
 107         struct snd_soc_dai *dai)
 108 {
 109         struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
 110         uint32_t mask;
 111         int ret;
 112
 113         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 114                 mask = AXI_I2S_RESET_RX_FIFO;
 115         else
 116                 mask = AXI_I2S_RESET_TX_FIFO;
 117
 118         regmap_write(i2s->regmap, AXI_I2S_REG_RESET, mask);
 119
 120         ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
 121                            SNDRV_PCM_HW_PARAM_RATE,
 122                            &i2s->rate_constraints);
 123         if (ret)
 124                 return ret;
 125
 126         return clk_prepare_enable(i2s->clk_ref);
 127 }
 128
 129 static void axi_i2s_shutdown(struct snd_pcm_substream *substream,
 130         struct snd_soc_dai *dai)
 131 {
 132         struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
 133
 134         clk_disable_unprepare(i2s->clk_ref);
 135 }
 136
 137 static int axi_i2s_dai_probe(struct snd_soc_dai *dai)
 138 {
 139         struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
 140
 141         snd_soc_dai_init_dma_data(
 142                 dai,
 143                 i2s->has_playback ? &i2s->playback_dma_data : NULL,
 144                 i2s->has_capture  ? &i2s->capture_dma_data  : NULL);
 145
 146         return 0;
 147 }
 148
 149 static const struct snd_soc_dai_ops axi_i2s_dai_ops = {
 150         .startup = axi_i2s_startup,
 151         .shutdown = axi_i2s_shutdown,
 152         .trigger = axi_i2s_trigger,
 153         .hw_params = axi_i2s_hw_params,
 154 };
 155
 156 static struct snd_soc_dai_driver axi_i2s_dai = {
 157         .probe = axi_i2s_dai_probe,
 158         .ops = &axi_i2s_dai_ops,
 159         .symmetric_rates = 1,
 160 };
 161
 162 static const struct snd_soc_component_driver axi_i2s_component = {
 163         .name = "axi-i2s",
 164 };
 165
 166 static const struct regmap_config axi_i2s_regmap_config = {
 167         .reg_bits = 32,
 168         .reg_stride = 4,
 169         .val_bits = 32,
 170         .max_register = AXI_I2S_REG_STATUS,
 171 };
 172
 173 static void axi_i2s_parse_of(struct axi_i2s *i2s, const struct device_node *np)
 174 {
 175         struct property *dma_names;
 176         const char *dma_name;
 177
 178         of_property_for_each_string(np, "dma-names", dma_names, dma_name) {
 179                 if (strcmp(dma_name, "rx") == 0)
 180                         i2s->has_capture = true;
 181                 if (strcmp(dma_name, "tx") == 0)
 182                         i2s->has_playback = true;
 183         }
 184 }
 185
 186 static int axi_i2s_probe(struct platform_device *pdev)
 187 {
 188         struct resource *res;
 189         struct axi_i2s *i2s;
 190         void __iomem *base;
 191         int ret;
 192
 193         i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
 194         if (!i2s)
 195                 return -ENOMEM;
 196
 197         platform_set_drvdata(pdev, i2s);
 198
 199         axi_i2s_parse_of(i2s, pdev->dev.of_node);
 200
 201         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 202         base = devm_ioremap_resource(&pdev->dev, res);
 203         if (IS_ERR(base))
 204                 return PTR_ERR(base);
 205
 206         i2s->regmap = devm_regmap_init_mmio(&pdev->dev, base,
 207                 &axi_i2s_regmap_config);
 208         if (IS_ERR(i2s->regmap))
 209                 return PTR_ERR(i2s->regmap);
 210
 211         i2s->clk = devm_clk_get(&pdev->dev, "axi");
 212         if (IS_ERR(i2s->clk))
 213                 return PTR_ERR(i2s->clk);
 214
 215         i2s->clk_ref = devm_clk_get(&pdev->dev, "ref");
 216         if (IS_ERR(i2s->clk_ref))
 217                 return PTR_ERR(i2s->clk_ref);
 218
 219         ret = clk_prepare_enable(i2s->clk);
 220         if (ret)
 221                 return ret;
 222
 223         if (i2s->has_playback) {
 224                 axi_i2s_dai.playback.channels_min = 2;
 225                 axi_i2s_dai.playback.channels_max = 2;
 226                 axi_i2s_dai.playback.rates = SNDRV_PCM_RATE_KNOT;
 227                 axi_i2s_dai.playback.formats =
 228                         SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE;
 229
 230                 i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
 231                 i2s->playback_dma_data.addr_width = 4;
 232                 i2s->playback_dma_data.maxburst = 1;
 233         }
 234
 235         if (i2s->has_capture) {
 236                 axi_i2s_dai.capture.channels_min = 2;
 237                 axi_i2s_dai.capture.channels_max = 2;
 238                 axi_i2s_dai.capture.rates = SNDRV_PCM_RATE_KNOT;
 239                 axi_i2s_dai.capture.formats =
 240                         SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE;
 241
 242                 i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
 243                 i2s->capture_dma_data.addr_width = 4;
 244                 i2s->capture_dma_data.maxburst = 1;
 245         }
 246
 247         i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME;
 248         i2s->ratnum.den_step = 1;
 249         i2s->ratnum.den_min = 1;
 250         i2s->ratnum.den_max = 64;
 251
 252         i2s->rate_constraints.rats = &i2s->ratnum;
 253         i2s->rate_constraints.nrats = 1;
 254
 255         regmap_write(i2s->regmap, AXI_I2S_REG_RESET, AXI_I2S_RESET_GLOBAL);
 256
 257         ret = devm_snd_soc_register_component(&pdev->dev, &axi_i2s_component,
 258                                          &axi_i2s_dai, 1);
 259         if (ret)
 260                 goto err_clk_disable;
 261
 262         ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
 263         if (ret)
 264                 goto err_clk_disable;
 265
 266         dev_info(&pdev->dev, "probed, capture %s, playback %s\n",
 267                  i2s->has_capture ? "enabled" : "disabled",
 268                  i2s->has_playback ? "enabled" : "disabled");
 269
 270         return 0;
 271
 272 err_clk_disable:
 273         clk_disable_unprepare(i2s->clk);
 274         return ret;
 275 }
 276
 277 static int axi_i2s_dev_remove(struct platform_device *pdev)
 278 {
 279         struct axi_i2s *i2s = platform_get_drvdata(pdev);
 280
 281         clk_disable_unprepare(i2s->clk);
 282
 283         return 0;
 284 }
 285
 286 static const struct of_device_id axi_i2s_of_match[] = {
 287         { .compatible = "adi,axi-i2s-1.00.a", },
 288         {},
 289 };
 290 MODULE_DEVICE_TABLE(of, axi_i2s_of_match);
 291
 292 static struct platform_driver axi_i2s_driver = {
 293         .driver = {
 294                 .name = "axi-i2s",
 295                 .of_match_table = axi_i2s_of_match,
 296         },
 297         .probe = axi_i2s_probe,
 298         .remove = axi_i2s_dev_remove,
 299 };
 300 module_platform_driver(axi_i2s_driver);
 301
 302 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 303 MODULE_DESCRIPTION("AXI I2S driver");
 304 MODULE_LICENSE("GPL");