MLK-16929-2: sound: soc: fsl: imx pdm mic driver over SAI

i.MX Sound SoC Audio support for PDM mics on SAI
Set audio recording hardware constrains, support
Sample rates: 8000, 16000, 32000, 48000, 64000
PDM decimation factor property fixed to 64
Number of channels: 1

Signed-off-by: Adrian Alonso <adrian.alonso@nxp.com>
Reviewed-by: Shengjiu Wang <shengjiu.wang@nxp.com>

diff --git a/sound/soc/fsl/Kconfig b/sound/soc/fsl/Kconfig
index 893194e..0781565 100644 (file)
--- a/sound/soc/fsl/Kconfig
+++ b/sound/soc/fsl/Kconfig
@@ -488,6 +488,16 @@ config SND_SOC_IMX_CDNHDMI
          Say Y if you want to add support for SoC audio on an i.MX board with
          IMX CDN HDMI.
 
+config SND_SOC_IMX_PDM_MIC
+       tristate "SoC Audio support for i.MX boards with PDM mic on SAI"
+       depends on OF
+       select SND_SOC_IMX_PDM_DMA
+       select SND_SOC_FSL_SAI
+       help
+         SoC Audio support for i.MX boards with PDM microphones on SAI
+         Say Y if you want to add support for SoC Audio support for i.MX boards
+         with PDM microphones on SAI.
+
 endif # SND_IMX_SOC
 
 endmenu

diff --git a/sound/soc/fsl/Makefile b/sound/soc/fsl/Makefile
index ea1a501..b35dd17 100644 (file)
--- a/sound/soc/fsl/Makefile
+++ b/sound/soc/fsl/Makefile
@@ -82,6 +82,7 @@ snd-soc-imx-hdmi-objs := imx-hdmi.o
 snd-soc-imx-cdnhdmi-objs := imx-cdnhdmi.o
 snd-soc-imx-rpmsg-objs := imx-rpmsg.o
 snd-soc-imx-amix-objs := imx-amix.o
+snd-soc-imx-pdm-objs := imx-pdm.o
 
 obj-$(CONFIG_SND_SOC_EUKREA_TLV320) += snd-soc-eukrea-tlv320.o
 obj-$(CONFIG_SND_SOC_PHYCORE_AC97) += snd-soc-phycore-ac97.o
@@ -104,5 +105,6 @@ obj-$(CONFIG_SND_SOC_IMX_SI476X) += snd-soc-imx-si476x.o
 obj-$(CONFIG_SND_SOC_IMX_HDMI) += snd-soc-imx-hdmi.o
 obj-$(CONFIG_SND_SOC_IMX_AMIX) += snd-soc-imx-amix.o
 obj-$(CONFIG_SND_SOC_IMX_CDNHDMI) += snd-soc-imx-cdnhdmi.o
+obj-$(CONFIG_SND_SOC_IMX_PDM_MIC) += snd-soc-imx-pdm.o
 
 AFLAGS_hdmi_pcm.o := -march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp

diff --git a/sound/soc/fsl/imx-pdm.c b/sound/soc/fsl/imx-pdm.c
new file mode 100644 (file)
index 0000000..eea0830
--- /dev/null
+++ b/sound/soc/fsl/imx-pdm.c
@@ -0,0 +1,197 @@
+/*
+ * Copyright 2017 NXP.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <sound/soc.h>
+
+#include "fsl_sai.h"
+
+struct imx_pdm_data {
+       struct snd_soc_dai_link dai;
+       struct snd_soc_card card;
+       unsigned int decimation;
+};
+
+static u32 imx_pdm_mic_rates[] = { 8000, 16000, 32000, 48000, 64000 };
+static struct snd_pcm_hw_constraint_list imx_pdm_mic_rate_constrains = {
+       .count = ARRAY_SIZE(imx_pdm_mic_rates),
+       .list = imx_pdm_mic_rates,
+};
+static u32 imx_pdm_mic_channels[] = { 1 };
+static struct snd_pcm_hw_constraint_list imx_pdm_mic_channels_constrains = {
+       .count = ARRAY_SIZE(imx_pdm_mic_channels),
+       .list = imx_pdm_mic_channels,
+};
+
+static int imx_pdm_mic_startup(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct snd_pcm_runtime *runtime = substream->runtime;
+       struct snd_soc_card *card = rtd->card;
+       int ret;
+
+       ret = snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+                       &imx_pdm_mic_rate_constrains);
+       if (ret) {
+               dev_err(card->dev,
+                       "fail to set pcm hw rate constrains: %d\n", ret);
+               return ret;
+       }
+
+       ret = snd_pcm_hw_constraint_list(runtime, 0,
+               SNDRV_PCM_HW_PARAM_CHANNELS, &imx_pdm_mic_channels_constrains);
+       if (ret) {
+               dev_err(card->dev,
+                       "fail to set pcm hw channels constrains: %d", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int imx_pdm_mic_hw_params(struct snd_pcm_substream *substream,
+               struct snd_pcm_hw_params *params)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
+       struct snd_soc_card *card = rtd->card;
+       struct imx_pdm_data *data = snd_soc_card_get_drvdata(card);
+       unsigned int bitclk = params_rate(params) * data->decimation;
+       int ret;
+
+       /* set cpu dai format configuration */
+       ret = snd_soc_dai_set_fmt(cpu_dai, SND_SOC_DAIFMT_DSP_A |
+                       SND_SOC_DAIFMT_NB_NF | SND_SOC_DAIFMT_CBS_CFS);
+       if (ret) {
+               dev_err(card->dev, "fail to set cpu dai fmt: %d\n", ret);
+               return ret;
+       }
+       /* set tdm slots only one for now */
+       snd_soc_dai_set_tdm_slot(cpu_dai, 0, 0, 1, 32);
+       /* Set clock out */
+       ret = snd_soc_dai_set_sysclk(cpu_dai, FSL_SAI_CLK_MAST1,
+                       bitclk, SND_SOC_CLOCK_OUT);
+       if (ret) {
+               dev_err(card->dev, "fail to set cpu sysclk: %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static const struct snd_soc_ops imx_pdm_mic_ops = {
+       .startup = imx_pdm_mic_startup,
+       .hw_params = imx_pdm_mic_hw_params,
+};
+
+static int imx_pdm_mic_probe(struct platform_device *pdev)
+{
+       struct device_node *cpu_np = NULL;
+       struct device_node *np = pdev->dev.of_node;
+       struct platform_device *cpu_pdev;
+       struct imx_pdm_data *data;
+       int ret;
+
+       cpu_np = of_parse_phandle(np, "audio-cpu", 0);
+       if (!cpu_np) {
+               dev_err(&pdev->dev, "cpu dai phandle missing or invalid\n");
+               ret = -EINVAL;
+               goto fail;
+       }
+
+       cpu_pdev = of_find_device_by_node(cpu_np);
+       if (!cpu_pdev) {
+               dev_err(&pdev->dev, "fail to find SAI platform device\n");
+               ret = -EINVAL;
+               goto fail;
+       }
+
+       data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+       if (!data) {
+               ret = -ENOMEM;
+               goto fail;
+       }
+
+       ret = of_property_read_u32(np, "decimation", &data->decimation);
+       if (ret < 0) {
+               ret = -EINVAL;
+               goto fail;
+       }
+
+       data->dai.name = "pdm hifi";
+       data->dai.stream_name = "pdm hifi";
+       data->dai.codec_dai_name = "snd-soc-dummy-dai";
+       data->dai.codec_name = "snd-soc-dummy";
+       data->dai.cpu_dai_name = dev_name(&cpu_pdev->dev);
+       data->dai.platform_of_node = cpu_np;
+       data->dai.capture_only = "true";
+       data->dai.ops = &imx_pdm_mic_ops;
+
+       data->card.dev = &pdev->dev;
+       data->card.owner = THIS_MODULE;
+
+       ret = snd_soc_of_parse_card_name(&data->card, "model");
+       if (ret) {
+               dev_err(&pdev->dev, "fail to find card model name\n");
+               goto fail;
+       }
+
+       data->card.num_links = 1;
+       data->card.dai_link = &data->dai;
+
+       platform_set_drvdata(pdev, &data->card);
+       snd_soc_card_set_drvdata(&data->card, data);
+
+       ret = devm_snd_soc_register_card(&pdev->dev, &data->card);
+       if (ret) {
+               dev_err(&pdev->dev, "snd soc register card failed: %d\n", ret);
+               goto fail;
+       }
+
+       ret = 0;
+fail:
+       if (cpu_np)
+               of_node_put(cpu_np);
+
+       return ret;
+}
+
+static int imx_pdm_mic_remove(struct platform_device *pdev)
+{
+       struct imx_pdm_data *data = platform_get_drvdata(pdev);
+       /* unregister card */
+       snd_soc_unregister_card(&data->card);
+       return 0;
+}
+
+static const struct of_device_id imx_pdm_mic_dt_ids[] = {
+       { .compatible = "fsl,imx-pdm-mic", },
+       { /* sentinel*/ }
+};
+MODULE_DEVICE_TABLE(of, imx_pdm_mic_dt_ids);
+
+static struct platform_driver imx_pdm_mic_driver = {
+       .driver = {
+               .name = "imx-pdm-mic",
+               .pm = &snd_soc_pm_ops,
+               .of_match_table = imx_pdm_mic_dt_ids,
+       },
+       .probe = imx_pdm_mic_probe,
+       .remove = imx_pdm_mic_remove,
+};
+module_platform_driver(imx_pdm_mic_driver);
+
+MODULE_DESCRIPTION("NXP i.MX PDM mic ASoC machine driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:imx-pdm-mic");