ASoC: meson: gx: add sound card support

Add support for the sound card used on the amlogic GX SoC family

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200213155159.3235792-10-jbrunet@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/meson/Kconfig

@@ -101,6 +101,13 @@ config SND_MESON_CARD_UTILS
 config SND_MESON_CODEC_GLUE
 	tristate
 
+config SND_MESON_GX_SOUND_CARD
+	tristate "Amlogic GX Sound Card Support"
+	select SND_MESON_CARD_UTILS
+	imply SND_MESON_AIU
+	help
+	  Select Y or M to add support for the GXBB/GXL SoC sound card
+
 config SND_MESON_G12A_TOHDMITX
 	tristate "Amlogic G12A To HDMI TX Control Support"
 	select REGMAP_MMIO

sound/soc/meson/Makefile

@@ -21,6 +21,7 @@ snd-soc-meson-axg-spdifout-objs := axg-spdifout.o
 snd-soc-meson-axg-pdm-objs := axg-pdm.o
 snd-soc-meson-card-utils-objs := meson-card-utils.o
 snd-soc-meson-codec-glue-objs := meson-codec-glue.o
+snd-soc-meson-gx-sound-card-objs := gx-card.o
 snd-soc-meson-g12a-tohdmitx-objs := g12a-tohdmitx.o
 
 obj-$(CONFIG_SND_MESON_AIU) += snd-soc-meson-aiu.o
@@ -37,4 +38,5 @@ obj-$(CONFIG_SND_MESON_AXG_SPDIFOUT) += snd-soc-meson-axg-spdifout.o
 obj-$(CONFIG_SND_MESON_AXG_PDM) += snd-soc-meson-axg-pdm.o
 obj-$(CONFIG_SND_MESON_CARD_UTILS) += snd-soc-meson-card-utils.o
 obj-$(CONFIG_SND_MESON_CODEC_GLUE) += snd-soc-meson-codec-glue.o
+obj-$(CONFIG_SND_MESON_GX_SOUND_CARD) += snd-soc-meson-gx-sound-card.o
 obj-$(CONFIG_SND_MESON_G12A_TOHDMITX) += snd-soc-meson-g12a-tohdmitx.o

sound/soc/meson/gx-card.c

@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+//
+// Copyright (c) 2020 BayLibre, SAS.
+// Author: Jerome Brunet <jbrunet@baylibre.com>
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+
+#include "meson-card.h"
+
+struct gx_dai_link_i2s_data {
+	unsigned int mclk_fs;
+};
+
+/*
+ * Base params for the codec to codec links
+ * Those will be over-written by the CPU side of the link
+ */
+static const struct snd_soc_pcm_stream codec_params = {
+	.formats = SNDRV_PCM_FMTBIT_S24_LE,
+	.rate_min = 5525,
+	.rate_max = 192000,
+	.channels_min = 1,
+	.channels_max = 8,
+};
+
+static int gx_card_i2s_be_hw_params(struct snd_pcm_substream *substream,
+				    struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct meson_card *priv = snd_soc_card_get_drvdata(rtd->card);
+	struct gx_dai_link_i2s_data *be =
+		(struct gx_dai_link_i2s_data *)priv->link_data[rtd->num];
+
+	return meson_card_i2s_set_sysclk(substream, params, be->mclk_fs);
+}
+
+static const struct snd_soc_ops gx_card_i2s_be_ops = {
+	.hw_params = gx_card_i2s_be_hw_params,
+};
+
+static int gx_card_parse_i2s(struct snd_soc_card *card,
+			     struct device_node *node,
+			     int *index)
+{
+	struct meson_card *priv = snd_soc_card_get_drvdata(card);
+	struct snd_soc_dai_link *link = &card->dai_link[*index];
+	struct gx_dai_link_i2s_data *be;
+
+	/* Allocate i2s link parameters */
+	be = devm_kzalloc(card->dev, sizeof(*be), GFP_KERNEL);
+	if (!be)
+		return -ENOMEM;
+	priv->link_data[*index] = be;
+
+	/* Setup i2s link */
+	link->ops = &gx_card_i2s_be_ops;
+	link->dai_fmt = meson_card_parse_daifmt(node, link->cpus->of_node);
+
+	of_property_read_u32(node, "mclk-fs", &be->mclk_fs);
+
+	return 0;
+}
+
+static int gx_card_cpu_identify(struct snd_soc_dai_link_component *c,
+				char *match)
+{
+	if (of_device_is_compatible(c->of_node, DT_PREFIX "aiu")) {
+		if (strstr(c->dai_name, match))
+			return 1;
+	}
+
+	/* dai not matched */
+	return 0;
+}
+
+static int gx_card_add_link(struct snd_soc_card *card, struct device_node *np,
+			    int *index)
+{
+	struct snd_soc_dai_link *dai_link = &card->dai_link[*index];
+	struct snd_soc_dai_link_component *cpu;
+	int ret;
+
+	cpu = devm_kzalloc(card->dev, sizeof(*cpu), GFP_KERNEL);
+	if (!cpu)
+		return -ENOMEM;
+
+	dai_link->cpus = cpu;
+	dai_link->num_cpus = 1;
+
+	ret = meson_card_parse_dai(card, np, &dai_link->cpus->of_node,
+				   &dai_link->cpus->dai_name);
+	if (ret)
+		return ret;
+
+	if (gx_card_cpu_identify(dai_link->cpus, "FIFO"))
+		ret = meson_card_set_fe_link(card, dai_link, np, true);
+	else
+		ret = meson_card_set_be_link(card, dai_link, np);
+
+	if (ret)
+		return ret;
+
+	/* Check if the cpu is the i2s encoder and parse i2s data */
+	if (gx_card_cpu_identify(dai_link->cpus, "I2S Encoder"))
+		ret = gx_card_parse_i2s(card, np, index);
+
+	/* Or apply codec to codec params if necessary */
+	else if (gx_card_cpu_identify(dai_link->cpus, "CODEC CTRL"))
+		dai_link->params = &codec_params;
+
+	return ret;
+}
+
+static const struct meson_card_match_data gx_card_match_data = {
+	.add_link = gx_card_add_link,
+};
+
+static const struct of_device_id gx_card_of_match[] = {
+	{
+		.compatible = "amlogic,gx-sound-card",
+		.data = &gx_card_match_data,
+	}, {}
+};
+MODULE_DEVICE_TABLE(of, gx_card_of_match);
+
+static struct platform_driver gx_card_pdrv = {
+	.probe = meson_card_probe,
+	.remove = meson_card_remove,
+	.driver = {
+		.name = "gx-sound-card",
+		.of_match_table = gx_card_of_match,
+	},
+};
+module_platform_driver(gx_card_pdrv);
+
+MODULE_DESCRIPTION("Amlogic GX ALSA machine driver");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL v2");