ASoC: amd: add acp6x pdm platform driver

PDM platform driver binds to the platform device created by
ACP6x PCI device. PDM driver registers ALSA DMA and CPU DAI
components with ASoC framework.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Link: https://lore.kernel.org/r/20211018112044.1705805-6-Vijendar.Mukunda@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/yc/acp6x-pdm-dma.c

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AMD ALSA SoC Yellow Carp PDM Driver
+ *
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+#include "acp6x.h"
+
+#define DRV_NAME "acp_yc_pdm_dma"
+
+static struct snd_soc_dai_driver acp6x_pdm_dai_driver = {
+	.capture = {
+		.rates = SNDRV_PCM_RATE_48000,
+		.formats = SNDRV_PCM_FMTBIT_S32_LE,
+		.channels_min = 2,
+		.channels_max = 2,
+		.rate_min = 48000,
+		.rate_max = 48000,
+	},
+};
+
+static const struct snd_soc_component_driver acp6x_pdm_component = {
+	.name		= DRV_NAME,
+};
+
+static int acp6x_pdm_audio_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct pdm_dev_data *adata;
+	int status;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "IORESOURCE_MEM FAILED\n");
+		return -ENODEV;
+	}
+
+	adata = devm_kzalloc(&pdev->dev, sizeof(*adata), GFP_KERNEL);
+	if (!adata)
+		return -ENOMEM;
+
+	adata->acp6x_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!adata->acp6x_base)
+		return -ENOMEM;
+
+	adata->capture_stream = NULL;
+
+	dev_set_drvdata(&pdev->dev, adata);
+	status = devm_snd_soc_register_component(&pdev->dev,
+						 &acp6x_pdm_component,
+						 &acp6x_pdm_dai_driver, 1);
+	if (status) {
+		dev_err(&pdev->dev, "Fail to register acp pdm dai\n");
+
+		return -ENODEV;
+	}
+	return 0;
+}
+
+static struct platform_driver acp6x_pdm_dma_driver = {
+	.probe = acp6x_pdm_audio_probe,
+	.driver = {
+		.name = "acp_yc_pdm_dma",
+	},
+};
+
+module_platform_driver(acp6x_pdm_dma_driver);
+
+MODULE_AUTHOR("Vijendar.Mukunda@amd.com");
+MODULE_DESCRIPTION("AMD ACP6x YC PDM Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRV_NAME);

sound/soc/amd/yc/acp6x.h

@@ -45,6 +45,11 @@ enum acp_config {
 	ACP_CONFIG_15,
 };
 
+struct pdm_dev_data {
+	void __iomem *acp6x_base;
+	struct snd_pcm_substream *capture_stream;
+};
+
 static inline u32 acp6x_readl(void __iomem *base_addr)
 {
 	return readl(base_addr - ACP6x_PHY_BASE_ADDRESS);