linux/sound/soc/xilinx/xlnx_spdif.c
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   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
  46struct 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
  55static 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
  77static 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
  97static 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
 105static 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
 149static 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
 168static 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
 198static 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
 205static 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
 216static 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
 227static const struct snd_soc_component_driver xlnx_spdif_component = {
 228        .name = "xlnx-spdif",
 229};
 230
 231static const struct of_device_id xlnx_spdif_of_match[] = {
 232        { .compatible = "xlnx,spdif-2.0", },
 233        {},
 234};
 235MODULE_DEVICE_TABLE(of, xlnx_spdif_of_match);
 236
 237static 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
 313clk_err:
 314        clk_disable_unprepare(ctx->axi_clk);
 315        return ret;
 316}
 317
 318static 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
 326static 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};
 334module_platform_driver(xlnx_spdif_driver);
 335
 336MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");
 337MODULE_DESCRIPTION("XILINX SPDIF driver");
 338MODULE_LICENSE("GPL v2");
 339