sound/soc/xilinx/xlnx_spdif.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Xilinx ASoC SPDIF audio support
   4 //
   5 // Copyright (C) 2018 Xilinx, Inc.
   6 //
   7 // Author: Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>
   8 //
   9
  10 #include <linux/clk.h>
  11 #include <linux/io.h>
  12 #include <linux/module.h>
  13 #include <linux/of.h>
  14 #include <linux/of_platform.h>
  15 #include <linux/platform_device.h>
  16 #include <sound/pcm_params.h>
  17 #include <sound/soc.h>
  18
  19 #define XLNX_SPDIF_RATES \
  20         (SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 | \
  21         SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 | \
  22         SNDRV_PCM_RATE_192000)
  23
  24 #define XLNX_SPDIF_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
  25
  26 #define XSPDIF_IRQ_STS_REG              0x20
  27 #define XSPDIF_IRQ_ENABLE_REG           0x28
  28 #define XSPDIF_SOFT_RESET_REG           0x40
  29 #define XSPDIF_CONTROL_REG              0x44
  30 #define XSPDIF_CHAN_0_STS_REG           0x4C
  31 #define XSPDIF_GLOBAL_IRQ_ENABLE_REG    0x1C
  32 #define XSPDIF_CH_A_USER_DATA_REG_0     0x64
  33
  34 #define XSPDIF_CORE_ENABLE_MASK         BIT(0)
  35 #define XSPDIF_FIFO_FLUSH_MASK          BIT(1)
  36 #define XSPDIF_CH_STS_MASK              BIT(5)
  37 #define XSPDIF_GLOBAL_IRQ_ENABLE        BIT(31)
  38 #define XSPDIF_CLOCK_CONFIG_BITS_MASK   GENMASK(5, 2)
  39 #define XSPDIF_CLOCK_CONFIG_BITS_SHIFT  2
  40 #define XSPDIF_SOFT_RESET_VALUE         0xA
  41
  42 #define MAX_CHANNELS                    2
  43 #define AES_SAMPLE_WIDTH                32
  44 #define CH_STATUS_UPDATE_TIMEOUT        40
  45
  46 struct spdif_dev_data {
  47         u32 mode;
  48         u32 aclk;
  49         bool rx_chsts_updated;
  50         void __iomem *base;
  51         struct clk *axi_clk;
  52         wait_queue_head_t chsts_q;
  53 };
  54
  55 static irqreturn_t xlnx_spdifrx_irq_handler(int irq, void *arg)
  56 {
  57         u32 val;
  58         struct spdif_dev_data *ctx = arg;
  59
  60         val = readl(ctx->base + XSPDIF_IRQ_STS_REG);
  61         if (val & XSPDIF_CH_STS_MASK) {
  62                 writel(val & XSPDIF_CH_STS_MASK,
  63                        ctx->base + XSPDIF_IRQ_STS_REG);
  64                 val = readl(ctx->base +
  65                             XSPDIF_IRQ_ENABLE_REG);
  66                 writel(val & ~XSPDIF_CH_STS_MASK,
  67                        ctx->base + XSPDIF_IRQ_ENABLE_REG);
  68
  69                 ctx->rx_chsts_updated = true;
  70                 wake_up_interruptible(&ctx->chsts_q);
  71                 return IRQ_HANDLED;
  72         }
  73
  74         return IRQ_NONE;
  75 }
  76
  77 static int xlnx_spdif_startup(struct snd_pcm_substream *substream,
  78                               struct snd_soc_dai *dai)
  79 {
  80         u32 val;
  81         struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
  82
  83         val = readl(ctx->base + XSPDIF_CONTROL_REG);
  84         val |= XSPDIF_FIFO_FLUSH_MASK;
  85         writel(val, ctx->base + XSPDIF_CONTROL_REG);
  86
  87         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
  88                 writel(XSPDIF_CH_STS_MASK,
  89                        ctx->base + XSPDIF_IRQ_ENABLE_REG);
  90                 writel(XSPDIF_GLOBAL_IRQ_ENABLE,
  91                        ctx->base + XSPDIF_GLOBAL_IRQ_ENABLE_REG);
  92         }
  93
  94         return 0;
  95 }
  96
  97 static void xlnx_spdif_shutdown(struct snd_pcm_substream *substream,
  98                                 struct snd_soc_dai *dai)
  99 {
 100         struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
 101
 102         writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
 103 }
 104
 105 static int xlnx_spdif_hw_params(struct snd_pcm_substream *substream,
 106                                 struct snd_pcm_hw_params *params,
 107                                 struct snd_soc_dai *dai)
 108 {
 109         u32 val, clk_div, clk_cfg;
 110         struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
 111
 112         clk_div = DIV_ROUND_CLOSEST(ctx->aclk, MAX_CHANNELS * AES_SAMPLE_WIDTH *
 113                                     params_rate(params));
 114
 115         switch (clk_div) {
 116         case 4:
 117                 clk_cfg = 0;
 118                 break;
 119         case 8:
 120                 clk_cfg = 1;
 121                 break;
 122         case 16:
 123                 clk_cfg = 2;
 124                 break;
 125         case 24:
 126                 clk_cfg = 3;
 127                 break;
 128         case 32:
 129                 clk_cfg = 4;
 130                 break;
 131         case 48:
 132                 clk_cfg = 5;
 133                 break;
 134         case 64:
 135                 clk_cfg = 6;
 136                 break;
 137         default:
 138                 return -EINVAL;
 139         }
 140
 141         val = readl(ctx->base + XSPDIF_CONTROL_REG);
 142         val &= ~XSPDIF_CLOCK_CONFIG_BITS_MASK;
 143         val |= clk_cfg << XSPDIF_CLOCK_CONFIG_BITS_SHIFT;
 144         writel(val, ctx->base + XSPDIF_CONTROL_REG);
 145
 146         return 0;
 147 }
 148
 149 static int rx_stream_detect(struct snd_soc_dai *dai)
 150 {
 151         int err;
 152         struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
 153         unsigned long jiffies = msecs_to_jiffies(CH_STATUS_UPDATE_TIMEOUT);
 154
 155         /* start capture only if stream is detected within 40ms timeout */
 156         err = wait_event_interruptible_timeout(ctx->chsts_q,
 157                                                ctx->rx_chsts_updated,
 158                                                jiffies);
 159         if (!err) {
 160                 dev_err(dai->dev, "No streaming audio detected!\n");
 161                 return -EINVAL;
 162         }
 163         ctx->rx_chsts_updated = false;
 164
 165         return 0;
 166 }
 167
 168 static int xlnx_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
 169                               struct snd_soc_dai *dai)
 170 {
 171         u32 val;
 172         int ret = 0;
 173         struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
 174
 175         val = readl(ctx->base + XSPDIF_CONTROL_REG);
 176         switch (cmd) {
 177         case SNDRV_PCM_TRIGGER_START:
 178         case SNDRV_PCM_TRIGGER_RESUME:
 179         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 180                 val |= XSPDIF_CORE_ENABLE_MASK;
 181                 writel(val, ctx->base + XSPDIF_CONTROL_REG);
 182                 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 183                         ret = rx_stream_detect(dai);
 184                 break;
 185         case SNDRV_PCM_TRIGGER_STOP:
 186         case SNDRV_PCM_TRIGGER_SUSPEND:
 187         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 188                 val &= ~XSPDIF_CORE_ENABLE_MASK;
 189                 writel(val, ctx->base + XSPDIF_CONTROL_REG);
 190                 break;
 191         default:
 192                 ret = -EINVAL;
 193         }
 194
 195         return ret;
 196 }
 197
 198 static const struct snd_soc_dai_ops xlnx_spdif_dai_ops = {
 199         .startup = xlnx_spdif_startup,
 200         .shutdown = xlnx_spdif_shutdown,
 201         .trigger = xlnx_spdif_trigger,
 202         .hw_params = xlnx_spdif_hw_params,
 203 };
 204
 205 static struct snd_soc_dai_driver xlnx_spdif_tx_dai = {
 206         .name = "xlnx_spdif_tx",
 207         .playback = {
 208                 .channels_min = 2,
 209                 .channels_max = 2,
 210                 .rates = XLNX_SPDIF_RATES,
 211                 .formats = XLNX_SPDIF_FORMATS,
 212         },
 213         .ops = &xlnx_spdif_dai_ops,
 214 };
 215
 216 static struct snd_soc_dai_driver xlnx_spdif_rx_dai = {
 217         .name = "xlnx_spdif_rx",
 218         .capture = {
 219                 .channels_min = 2,
 220                 .channels_max = 2,
 221                 .rates = XLNX_SPDIF_RATES,
 222                 .formats = XLNX_SPDIF_FORMATS,
 223         },
 224         .ops = &xlnx_spdif_dai_ops,
 225 };
 226
 227 static const struct snd_soc_component_driver xlnx_spdif_component = {
 228         .name = "xlnx-spdif",
 229 };
 230
 231 static const struct of_device_id xlnx_spdif_of_match[] = {
 232         { .compatible = "xlnx,spdif-2.0", },
 233         {},
 234 };
 235 MODULE_DEVICE_TABLE(of, xlnx_spdif_of_match);
 236
 237 static int xlnx_spdif_probe(struct platform_device *pdev)
 238 {
 239         int ret;
 240         struct resource *res;
 241         struct snd_soc_dai_driver *dai_drv;
 242         struct spdif_dev_data *ctx;
 243
 244         struct device *dev = &pdev->dev;
 245         struct device_node *node = dev->of_node;
 246
 247         ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
 248         if (!ctx)
 249                 return -ENOMEM;
 250
 251         ctx->axi_clk = devm_clk_get(dev, "s_axi_aclk");
 252         if (IS_ERR(ctx->axi_clk)) {
 253                 ret = PTR_ERR(ctx->axi_clk);
 254                 dev_err(dev, "failed to get s_axi_aclk(%d)\n", ret);
 255                 return ret;
 256         }
 257         ret = clk_prepare_enable(ctx->axi_clk);
 258         if (ret) {
 259                 dev_err(dev, "failed to enable s_axi_aclk(%d)\n", ret);
 260                 return ret;
 261         }
 262
 263         ctx->base = devm_platform_ioremap_resource(pdev, 0);
 264         if (IS_ERR(ctx->base)) {
 265                 ret = PTR_ERR(ctx->base);
 266                 goto clk_err;
 267         }
 268         ret = of_property_read_u32(node, "xlnx,spdif-mode", &ctx->mode);
 269         if (ret < 0) {
 270                 dev_err(dev, "cannot get SPDIF mode\n");
 271                 goto clk_err;
 272         }
 273         if (ctx->mode) {
 274                 dai_drv = &xlnx_spdif_tx_dai;
 275         } else {
 276                 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 277                 if (!res) {
 278                         dev_err(dev, "No IRQ resource found\n");
 279                         ret = -ENODEV;
 280                         goto clk_err;
 281                 }
 282                 ret = devm_request_irq(dev, res->start,
 283                                        xlnx_spdifrx_irq_handler,
 284                                        0, "XLNX_SPDIF_RX", ctx);
 285                 if (ret) {
 286                         dev_err(dev, "spdif rx irq request failed\n");
 287                         ret = -ENODEV;
 288                         goto clk_err;
 289                 }
 290
 291                 init_waitqueue_head(&ctx->chsts_q);
 292                 dai_drv = &xlnx_spdif_rx_dai;
 293         }
 294
 295         ret = of_property_read_u32(node, "xlnx,aud_clk_i", &ctx->aclk);
 296         if (ret < 0) {
 297                 dev_err(dev, "cannot get aud_clk_i value\n");
 298                 goto clk_err;
 299         }
 300
 301         dev_set_drvdata(dev, ctx);
 302
 303         ret = devm_snd_soc_register_component(dev, &xlnx_spdif_component,
 304                                               dai_drv, 1);
 305         if (ret) {
 306                 dev_err(dev, "SPDIF component registration failed\n");
 307                 goto clk_err;
 308         }
 309
 310         writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
 311         dev_info(dev, "%s DAI registered\n", dai_drv->name);
 312
 313 clk_err:
 314         clk_disable_unprepare(ctx->axi_clk);
 315         return ret;
 316 }
 317
 318 static int xlnx_spdif_remove(struct platform_device *pdev)
 319 {
 320         struct spdif_dev_data *ctx = dev_get_drvdata(&pdev->dev);
 321
 322         clk_disable_unprepare(ctx->axi_clk);
 323         return 0;
 324 }
 325
 326 static struct platform_driver xlnx_spdif_driver = {
 327         .driver = {
 328                 .name = "xlnx-spdif",
 329                 .of_match_table = xlnx_spdif_of_match,
 330         },
 331         .probe = xlnx_spdif_probe,
 332         .remove = xlnx_spdif_remove,
 333 };
 334 module_platform_driver(xlnx_spdif_driver);
 335
 336 MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");
 337 MODULE_DESCRIPTION("XILINX SPDIF driver");
 338 MODULE_LICENSE("GPL v2");