ASoC: xlnx: Add i2s driver

I2S IP instance can work in transmitter/playback or receiver/capture mode
exclusively. The patch registers corresponding instance as ASoC component
with audio framework.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/xilinx/xlnx_i2s.c b/sound/soc/xilinx/xlnx_i2s.c
new file mode 100644 (file)
index 0000000..d4ae9ef
--- /dev/null
+++ b/sound/soc/xilinx/xlnx_i2s.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx ASoC I2S audio support
+ *
+ * Copyright (C) 2018 Xilinx, Inc.
+ *
+ * Author: Praveen Vuppala <praveenv@xilinx.com>
+ * Author: Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define DRV_NAME "xlnx_i2s"
+
+#define I2S_CORE_CTRL_OFFSET           0x08
+#define I2S_I2STIM_OFFSET              0x20
+#define I2S_CH0_OFFSET                 0x30
+#define I2S_I2STIM_VALID_MASK          GENMASK(7, 0)
+
+static int xlnx_i2s_set_sclkout_div(struct snd_soc_dai *cpu_dai,
+                                   int div_id, int div)
+{
+       void __iomem *base = snd_soc_dai_get_drvdata(cpu_dai);
+
+       if (!div || (div & ~I2S_I2STIM_VALID_MASK))
+               return -EINVAL;
+
+       writel(div, base + I2S_I2STIM_OFFSET);
+
+       return 0;
+}
+
+static int xlnx_i2s_hw_params(struct snd_pcm_substream *substream,
+                             struct snd_pcm_hw_params *params,
+                             struct snd_soc_dai *i2s_dai)
+{
+       u32 reg_off, chan_id;
+       void __iomem *base = snd_soc_dai_get_drvdata(i2s_dai);
+
+       chan_id = params_channels(params) / 2;
+
+       while (chan_id > 0) {
+               reg_off = I2S_CH0_OFFSET + ((chan_id - 1) * 4);
+               writel(chan_id, base + reg_off);
+               chan_id--;
+       }
+
+       return 0;
+}
+
+static int xlnx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
+                           struct snd_soc_dai *i2s_dai)
+{
+       void __iomem *base = snd_soc_dai_get_drvdata(i2s_dai);
+
+       switch (cmd) {
+       case SNDRV_PCM_TRIGGER_START:
+       case SNDRV_PCM_TRIGGER_RESUME:
+       case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+               writel(1, base + I2S_CORE_CTRL_OFFSET);
+               break;
+       case SNDRV_PCM_TRIGGER_STOP:
+       case SNDRV_PCM_TRIGGER_SUSPEND:
+       case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+               writel(0, base + I2S_CORE_CTRL_OFFSET);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static const struct snd_soc_dai_ops xlnx_i2s_dai_ops = {
+       .trigger = xlnx_i2s_trigger,
+       .set_clkdiv = xlnx_i2s_set_sclkout_div,
+       .hw_params = xlnx_i2s_hw_params
+};
+
+static const struct snd_soc_component_driver xlnx_i2s_component = {
+       .name = DRV_NAME,
+};
+
+static const struct of_device_id xlnx_i2s_of_match[] = {
+       { .compatible = "xlnx,i2s-transmitter-1.0", },
+       { .compatible = "xlnx,i2s-receiver-1.0", },
+       {},
+};
+MODULE_DEVICE_TABLE(of, xlnx_i2s_of_match);
+
+static int xlnx_i2s_probe(struct platform_device *pdev)
+{
+       struct resource *res;
+       void __iomem *base;
+       struct snd_soc_dai_driver *dai_drv;
+       int ret;
+       u32 ch, format, data_width;
+       struct device *dev = &pdev->dev;
+       struct device_node *node = dev->of_node;
+
+       dai_drv = devm_kzalloc(&pdev->dev, sizeof(*dai_drv), GFP_KERNEL);
+       if (!dai_drv)
+               return -ENOMEM;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(base))
+               return PTR_ERR(base);
+
+       ret = of_property_read_u32(node, "xlnx,num-channels", &ch);
+       if (ret < 0) {
+               dev_err(dev, "cannot get supported channels\n");
+               return ret;
+       }
+       ch = ch * 2;
+
+       ret = of_property_read_u32(node, "xlnx,dwidth", &data_width);
+       if (ret < 0) {
+               dev_err(dev, "cannot get data width\n");
+               return ret;
+       }
+       switch (data_width) {
+       case 16:
+               format = SNDRV_PCM_FMTBIT_S16_LE;
+               break;
+       case 24:
+               format = SNDRV_PCM_FMTBIT_S24_LE;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       if (of_device_is_compatible(node, "xlnx,i2s-transmitter-1.0")) {
+               dai_drv->name = "xlnx_i2s_playback";
+               dai_drv->playback.stream_name = "Playback";
+               dai_drv->playback.formats = format;
+               dai_drv->playback.channels_min = ch;
+               dai_drv->playback.channels_max = ch;
+               dai_drv->playback.rates = SNDRV_PCM_RATE_8000_192000;
+               dai_drv->ops = &xlnx_i2s_dai_ops;
+       } else if (of_device_is_compatible(node, "xlnx,i2s-receiver-1.0")) {
+               dai_drv->name = "xlnx_i2s_capture";
+               dai_drv->capture.stream_name = "Capture";
+               dai_drv->capture.formats = format;
+               dai_drv->capture.channels_min = ch;
+               dai_drv->capture.channels_max = ch;
+               dai_drv->capture.rates = SNDRV_PCM_RATE_8000_192000;
+               dai_drv->ops = &xlnx_i2s_dai_ops;
+       } else {
+               return -ENODEV;
+       }
+
+       dev_set_drvdata(&pdev->dev, base);
+
+       ret = devm_snd_soc_register_component(&pdev->dev, &xlnx_i2s_component,
+                                             dai_drv, 1);
+       if (ret) {
+               dev_err(&pdev->dev, "i2s component registration failed\n");
+               return ret;
+       }
+
+       dev_info(&pdev->dev, "%s DAI registered\n", dai_drv->name);
+
+       return ret;
+}
+
+static struct platform_driver xlnx_i2s_aud_driver = {
+       .driver = {
+               .name = DRV_NAME,
+               .of_match_table = xlnx_i2s_of_match,
+       },
+       .probe = xlnx_i2s_probe,
+};
+
+module_platform_driver(xlnx_i2s_aud_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Praveen Vuppala  <praveenv@xilinx.com>");
+MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");