path: root/target/linux/bcm27xx/patches-5.4/950-0070-Add-support-for-Allo-Boss-DAC-add-on-board-for-Raspb.patch

From 7a13759deeaae55840571574e32e00f0e5902661 Mon Sep 17 00:00:00 2001
From: BabuSubashChandar <babuenir@gmail.com>
Date: Tue, 28 Mar 2017 20:04:42 +0530
Subject: [PATCH] Add support for Allo Boss DAC add-on board for
 Raspberry Pi. (#1924)

Signed-off-by: Baswaraj K <jaikumar@cem-solutions.net>
Reviewed-by: Deepak <deepak@zilogic.com>
Reviewed-by: BabuSubashChandar <babusubashchandar@zilogic.com>

Add support for new clock rate and mute gpios.

Signed-off-by: Baswaraj K <jaikumar@cem-solutions.net>
Reviewed-by: Deepak <deepak@zilogic.com>
Reviewed-by: BabuSubashChandar <babusubashchandar@zilogic.com>

ASoC: allo-boss-dac: fix S24_LE format

Remove set_bclk_ratio call so 24-bit data is transmitted in
24 bclk cycles.

Signed-off-by: Matthias Reichl <hias@horus.com>

ASoC: allo-boss-dac: transmit S24_LE with 64 BCLK cycles

Signed-off-by: Matthias Reichl <hias@horus.com>

allo-boss-dac: switch to snd_soc_dai_set_bclk_ratio

Signed-off-by: Matthias Reichl <hias@horus.com>

ASoC: allo-boss-dac: use modern dai_link style

Signed-off-by: Hui Wang <hui.wang@canonical.com>
---
 drivers/clk/Makefile          |   1 +
 drivers/clk/clk-allo-dac.c    | 161 ++++++++++++
 sound/soc/bcm/allo-boss-dac.c | 456 ++++++++++++++++++++++++++++++++++
 3 files changed, 618 insertions(+)
 create mode 100644 drivers/clk/clk-allo-dac.c
 create mode 100644 sound/soc/bcm/allo-boss-dac.c

--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -18,6 +18,7 @@ endif
 
 # hardware specific clock types
 # please keep this section sorted lexicographically by file path name
+obj-$(CONFIG_SND_BCM2708_SOC_ALLO_BOSS_DAC)	+= clk-allo-dac.o
 obj-$(CONFIG_MACH_ASM9260)		+= clk-asm9260.o
 obj-$(CONFIG_COMMON_CLK_AXI_CLKGEN)	+= clk-axi-clkgen.o
 obj-$(CONFIG_ARCH_AXXIA)		+= clk-axm5516.o
--- /dev/null
+++ b/drivers/clk/clk-allo-dac.c
@@ -0,0 +1,161 @@
+/*
+ * Clock Driver for Allo DAC
+ *
+ * Author:	Baswaraj K <jaikumar@cem-solutions.net>
+ *		Copyright 2016
+ *		based on code by Stuart MacLean
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+
+/* Clock rate of CLK44EN attached to GPIO6 pin */
+#define CLK_44EN_RATE 45158400UL
+/* Clock rate of CLK48EN attached to GPIO3 pin */
+#define CLK_48EN_RATE 49152000UL
+
+/**
+ * struct allo_dac_clk - Common struct to the Allo DAC
+ * @hw: clk_hw for the common clk framework
+ * @mode: 0 => CLK44EN, 1 => CLK48EN
+ */
+struct clk_allo_hw {
+	struct clk_hw hw;
+	uint8_t mode;
+};
+
+#define to_allo_clk(_hw) container_of(_hw, struct clk_allo_hw, hw)
+
+static const struct of_device_id clk_allo_dac_dt_ids[] = {
+	{ .compatible = "allo,dac-clk",},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, clk_allo_dac_dt_ids);
+
+static unsigned long clk_allo_dac_recalc_rate(struct clk_hw *hw,
+	unsigned long parent_rate)
+{
+	return (to_allo_clk(hw)->mode == 0) ? CLK_44EN_RATE :
+		CLK_48EN_RATE;
+}
+
+static long clk_allo_dac_round_rate(struct clk_hw *hw,
+	unsigned long rate, unsigned long *parent_rate)
+{
+	long actual_rate;
+
+	if (rate <= CLK_44EN_RATE) {
+		actual_rate = (long)CLK_44EN_RATE;
+	} else if (rate >= CLK_48EN_RATE) {
+		actual_rate = (long)CLK_48EN_RATE;
+	} else {
+		long diff44Rate = (long)(rate - CLK_44EN_RATE);
+		long diff48Rate = (long)(CLK_48EN_RATE - rate);
+
+		if (diff44Rate < diff48Rate)
+			actual_rate = (long)CLK_44EN_RATE;
+		else
+			actual_rate = (long)CLK_48EN_RATE;
+	}
+	return actual_rate;
+}
+
+
+static int clk_allo_dac_set_rate(struct clk_hw *hw,
+	unsigned long rate, unsigned long parent_rate)
+{
+	unsigned long actual_rate;
+	struct clk_allo_hw *clk = to_allo_clk(hw);
+
+	actual_rate = (unsigned long)clk_allo_dac_round_rate(hw, rate,
+		&parent_rate);
+	clk->mode = (actual_rate == CLK_44EN_RATE) ? 0 : 1;
+	return 0;
+}
+
+
+const struct clk_ops clk_allo_dac_rate_ops = {
+	.recalc_rate = clk_allo_dac_recalc_rate,
+	.round_rate = clk_allo_dac_round_rate,
+	.set_rate = clk_allo_dac_set_rate,
+};
+
+static int clk_allo_dac_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct clk_allo_hw *proclk;
+	struct clk *clk;
+	struct device *dev;
+	struct clk_init_data init;
+
+	dev = &pdev->dev;
+
+	proclk = kzalloc(sizeof(struct clk_allo_hw), GFP_KERNEL);
+	if (!proclk)
+		return -ENOMEM;
+
+	init.name = "clk-allo-dac";
+	init.ops = &clk_allo_dac_rate_ops;
+	init.flags = 0;
+	init.parent_names = NULL;
+	init.num_parents = 0;
+
+	proclk->mode = 0;
+	proclk->hw.init = &init;
+
+	clk = devm_clk_register(dev, &proclk->hw);
+	if (!IS_ERR(clk)) {
+		ret = of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
+			clk);
+	} else {
+		dev_err(dev, "Fail to register clock driver\n");
+		kfree(proclk);
+		ret = PTR_ERR(clk);
+	}
+	return ret;
+}
+
+static int clk_allo_dac_remove(struct platform_device *pdev)
+{
+	of_clk_del_provider(pdev->dev.of_node);
+	return 0;
+}
+
+static struct platform_driver clk_allo_dac_driver = {
+	.probe = clk_allo_dac_probe,
+	.remove = clk_allo_dac_remove,
+	.driver = {
+		.name = "clk-allo-dac",
+		.of_match_table = clk_allo_dac_dt_ids,
+	},
+};
+
+static int __init clk_allo_dac_init(void)
+{
+	return platform_driver_register(&clk_allo_dac_driver);
+}
+core_initcall(clk_allo_dac_init);
+
+static void __exit clk_allo_dac_exit(void)
+{
+	platform_driver_unregister(&clk_allo_dac_driver);
+}
+module_exit(clk_allo_dac_exit);
+
+MODULE_DESCRIPTION("Allo DAC clock driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:clk-allo-dac");
--- /dev/null
+++ b/sound/soc/bcm/allo-boss-dac.c
@@ -0,0 +1,456 @@
+/*
+ * ALSA ASoC Machine Driver for Allo Boss DAC
+ *
+ * Author:	Baswaraj K <jaikumar@cem-solutions.net>
+ *		Copyright 2017
+ *		based on code by Daniel Matuschek,
+ *				 Stuart MacLean <stuart@hifiberry.com>
+ *		based on code by Florian Meier <florian.meier@koalo.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include "../codecs/pcm512x.h"
+
+#define ALLO_BOSS_NOCLOCK 0
+#define ALLO_BOSS_CLK44EN 1
+#define ALLO_BOSS_CLK48EN 2
+
+struct pcm512x_priv {
+	struct regmap *regmap;
+	struct clk *sclk;
+};
+
+static struct gpio_desc *mute_gpio;
+
+/* Clock rate of CLK44EN attached to GPIO6 pin */
+#define CLK_44EN_RATE 45158400UL
+/* Clock rate of CLK48EN attached to GPIO3 pin */
+#define CLK_48EN_RATE 49152000UL
+
+static bool slave;
+static bool snd_soc_allo_boss_master;
+static bool digital_gain_0db_limit = true;
+
+static void snd_allo_boss_select_clk(struct snd_soc_component *component,
+	int clk_id)
+{
+	switch (clk_id) {
+	case ALLO_BOSS_NOCLOCK:
+		snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x24, 0x00);
+		break;
+	case ALLO_BOSS_CLK44EN:
+		snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x24, 0x20);
+		break;
+	case ALLO_BOSS_CLK48EN:
+		snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x24, 0x04);
+		break;
+	}
+}
+
+static void snd_allo_boss_clk_gpio(struct snd_soc_component *component)
+{
+	snd_soc_component_update_bits(component, PCM512x_GPIO_EN, 0x24, 0x24);
+	snd_soc_component_update_bits(component, PCM512x_GPIO_OUTPUT_3, 0x0f, 0x02);
+	snd_soc_component_update_bits(component, PCM512x_GPIO_OUTPUT_6, 0x0f, 0x02);
+}
+
+static bool snd_allo_boss_is_sclk(struct snd_soc_component *component)
+{
+	unsigned int sck;
+
+	snd_soc_component_read(component, PCM512x_RATE_DET_4, &sck);
+	return (!(sck & 0x40));
+}
+
+static bool snd_allo_boss_is_sclk_sleep(
+	struct snd_soc_component *component)
+{
+	msleep(2);
+	return snd_allo_boss_is_sclk(component);
+}
+
+static bool snd_allo_boss_is_master_card(struct snd_soc_component *component)
+{
+	bool isClk44EN, isClk48En, isNoClk;
+
+	snd_allo_boss_clk_gpio(component);
+
+	snd_allo_boss_select_clk(component, ALLO_BOSS_CLK44EN);
+	isClk44EN = snd_allo_boss_is_sclk_sleep(component);
+
+	snd_allo_boss_select_clk(component, ALLO_BOSS_NOCLOCK);
+	isNoClk = snd_allo_boss_is_sclk_sleep(component);
+
+	snd_allo_boss_select_clk(component, ALLO_BOSS_CLK48EN);
+	isClk48En = snd_allo_boss_is_sclk_sleep(component);
+
+	return (isClk44EN && isClk48En && !isNoClk);
+}
+
+static int snd_allo_boss_clk_for_rate(int sample_rate)
+{
+	int type;
+
+	switch (sample_rate) {
+	case 11025:
+	case 22050:
+	case 44100:
+	case 88200:
+	case 176400:
+	case 352800:
+		type = ALLO_BOSS_CLK44EN;
+		break;
+	default:
+		type = ALLO_BOSS_CLK48EN;
+		break;
+	}
+	return type;
+}
+
+static void snd_allo_boss_set_sclk(struct snd_soc_component *component,
+	int sample_rate)
+{
+	struct pcm512x_priv *pcm512x = snd_soc_component_get_drvdata(component);
+
+	if (!IS_ERR(pcm512x->sclk)) {
+		int ctype;
+
+		ctype =	snd_allo_boss_clk_for_rate(sample_rate);
+		clk_set_rate(pcm512x->sclk, (ctype == ALLO_BOSS_CLK44EN)
+				? CLK_44EN_RATE : CLK_48EN_RATE);
+		snd_allo_boss_select_clk(component, ctype);
+	}
+}
+
+static int snd_allo_boss_init(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	struct pcm512x_priv *priv = snd_soc_component_get_drvdata(component);
+
+	if (slave)
+		snd_soc_allo_boss_master = false;
+	else
+		snd_soc_allo_boss_master =
+			snd_allo_boss_is_master_card(component);
+
+	if (snd_soc_allo_boss_master) {
+		struct snd_soc_dai_link *dai = rtd->dai_link;
+
+		dai->name = "BossDAC";
+		dai->stream_name = "Boss DAC HiFi [Master]";
+		dai->dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF
+			| SND_SOC_DAIFMT_CBM_CFM;
+
+		snd_soc_component_update_bits(component, PCM512x_BCLK_LRCLK_CFG, 0x31, 0x11);
+		snd_soc_component_update_bits(component, PCM512x_MASTER_MODE, 0x03, 0x03);
+		snd_soc_component_update_bits(component, PCM512x_MASTER_CLKDIV_2, 0x7f, 63);
+		/*
+		* Default sclk to CLK_48EN_RATE, otherwise codec
+		*  pcm512x_dai_startup_master method could call
+		*  snd_pcm_hw_constraint_ratnums using CLK_44EN/64
+		*  which will mask 384k sample rate.
+		*/
+		if (!IS_ERR(priv->sclk))
+			clk_set_rate(priv->sclk, CLK_48EN_RATE);
+	} else {
+		priv->sclk = ERR_PTR(-ENOENT);
+	}
+
+	snd_soc_component_update_bits(component, PCM512x_GPIO_EN, 0x08, 0x08);
+	snd_soc_component_update_bits(component, PCM512x_GPIO_OUTPUT_4, 0x0f, 0x02);
+	snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x08, 0x08);
+
+	if (digital_gain_0db_limit) {
+		int ret;
+		struct snd_soc_card *card = rtd->card;
+
+		ret = snd_soc_limit_volume(card, "Digital Playback Volume",
+				207);
+		if (ret < 0)
+			dev_warn(card->dev, "Failed to set volume limit: %d\n",
+					ret);
+	}
+
+	return 0;
+}
+
+static int snd_allo_boss_update_rate_den(
+	struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	struct pcm512x_priv *pcm512x = snd_soc_component_get_drvdata(component);
+	struct snd_ratnum *rats_no_pll;
+	unsigned int num = 0, den = 0;
+	int err;
+
+	rats_no_pll = devm_kzalloc(rtd->dev, sizeof(*rats_no_pll), GFP_KERNEL);
+	if (!rats_no_pll)
+		return -ENOMEM;
+
+	rats_no_pll->num = clk_get_rate(pcm512x->sclk) / 64;
+	rats_no_pll->den_min = 1;
+	rats_no_pll->den_max = 128;
+	rats_no_pll->den_step = 1;
+
+	err = snd_interval_ratnum(hw_param_interval(params,
+		SNDRV_PCM_HW_PARAM_RATE), 1, rats_no_pll, &num, &den);
+	if (err >= 0 && den) {
+		params->rate_num = num;
+		params->rate_den = den;
+	}
+
+	devm_kfree(rtd->dev, rats_no_pll);
+	return 0;
+}
+
+static void snd_allo_boss_gpio_mute(struct snd_soc_card *card)
+{
+	if (mute_gpio)
+		gpiod_set_value_cansleep(mute_gpio, 1);
+}
+
+static void snd_allo_boss_gpio_unmute(struct snd_soc_card *card)
+{
+	if (mute_gpio)
+		gpiod_set_value_cansleep(mute_gpio, 0);
+}
+
+static int snd_allo_boss_set_bias_level(struct snd_soc_card *card,
+	struct snd_soc_dapm_context *dapm, enum snd_soc_bias_level level)
+{
+	struct snd_soc_pcm_runtime *rtd;
+	struct snd_soc_dai *codec_dai;
+
+	rtd = snd_soc_get_pcm_runtime(card, card->dai_link[0].name);
+	codec_dai = rtd->codec_dai;
+
+	if (dapm->dev != codec_dai->dev)
+		return 0;
+
+	switch (level) {
+	case SND_SOC_BIAS_PREPARE:
+		if (dapm->bias_level != SND_SOC_BIAS_STANDBY)
+			break;
+		/* UNMUTE DAC */
+		snd_allo_boss_gpio_unmute(card);
+		break;
+
+	case SND_SOC_BIAS_STANDBY:
+		if (dapm->bias_level != SND_SOC_BIAS_PREPARE)
+			break;
+		/* MUTE DAC */
+		snd_allo_boss_gpio_mute(card);
+		break;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int snd_allo_boss_hw_params(
+	struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params)
+{
+	int ret = 0;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	int channels = params_channels(params);
+	int width = snd_pcm_format_physical_width(params_format(params));
+
+	if (snd_soc_allo_boss_master) {
+		struct snd_soc_component *component = rtd->codec_dai->component;
+
+		snd_allo_boss_set_sclk(component,
+			params_rate(params));
+
+		ret = snd_allo_boss_update_rate_den(
+			substream, params);
+		if (ret)
+			return ret;
+	}
+
+	ret = snd_soc_dai_set_bclk_ratio(rtd->cpu_dai, channels * width);
+	if (ret)
+		return ret;
+	ret = snd_soc_dai_set_bclk_ratio(rtd->codec_dai, channels * width);
+	return ret;
+}
+
+static int snd_allo_boss_startup(
+	struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+	struct snd_soc_card *card = rtd->card;
+
+	snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x08, 0x08);
+	snd_allo_boss_gpio_mute(card);
+
+	if (snd_soc_allo_boss_master) {
+		struct pcm512x_priv *priv = snd_soc_component_get_drvdata(component);
+		/*
+		 * Default sclk to CLK_48EN_RATE, otherwise codec
+		 * pcm512x_dai_startup_master method could call
+		 * snd_pcm_hw_constraint_ratnums using CLK_44EN/64
+		 * which will mask 384k sample rate.
+		 */
+		if (!IS_ERR(priv->sclk))
+			clk_set_rate(priv->sclk, CLK_48EN_RATE);
+	}
+
+	return 0;
+}
+
+static void snd_allo_boss_shutdown(
+	struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_component *component = rtd->codec_dai->component;
+
+	snd_soc_component_update_bits(component, PCM512x_GPIO_CONTROL_1, 0x08, 0x00);
+}
+
+static int snd_allo_boss_prepare(
+	struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_card *card = rtd->card;
+
+	snd_allo_boss_gpio_unmute(card);
+	return 0;
+}
+/* machine stream operations */
+static struct snd_soc_ops snd_allo_boss_ops = {
+	.hw_params = snd_allo_boss_hw_params,
+	.startup = snd_allo_boss_startup,
+	.shutdown = snd_allo_boss_shutdown,
+	.prepare = snd_allo_boss_prepare,
+};
+
+SND_SOC_DAILINK_DEFS(allo_boss,
+	DAILINK_COMP_ARRAY(COMP_CPU("bcm2708-i2s.0")),
+	DAILINK_COMP_ARRAY(COMP_CODEC("pcm512x.1-004d", "pcm512x-hifi")),
+	DAILINK_COMP_ARRAY(COMP_PLATFORM("bcm2708-i2s.0")));
+
+static struct snd_soc_dai_link snd_allo_boss_dai[] = {
+{
+	.name		= "Boss DAC",
+	.stream_name	= "Boss DAC HiFi",
+	.dai_fmt	= SND_SOC_DAIFMT_I2S |
+			  SND_SOC_DAIFMT_NB_NF |
+			  SND_SOC_DAIFMT_CBS_CFS,
+	.ops		= &snd_allo_boss_ops,
+	.init		= snd_allo_boss_init,
+	SND_SOC_DAILINK_REG(allo_boss),
+},
+};
+
+/* audio machine driver */
+static struct snd_soc_card snd_allo_boss = {
+	.name         = "BossDAC",
+	.owner        = THIS_MODULE,
+	.dai_link     = snd_allo_boss_dai,
+	.num_links    = ARRAY_SIZE(snd_allo_boss_dai),
+};
+
+static int snd_allo_boss_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+
+	snd_allo_boss.dev = &pdev->dev;
+
+	if (pdev->dev.of_node) {
+		struct device_node *i2s_node;
+		struct snd_soc_dai_link *dai;
+
+		dai = &snd_allo_boss_dai[0];
+		i2s_node = of_parse_phandle(pdev->dev.of_node,
+					    "i2s-controller", 0);
+
+		if (i2s_node) {
+			dai->cpus->dai_name = NULL;
+			dai->cpus->of_node = i2s_node;
+			dai->platforms->name = NULL;
+			dai->platforms->of_node = i2s_node;
+		}
+
+		digital_gain_0db_limit = !of_property_read_bool(
+			pdev->dev.of_node, "allo,24db_digital_gain");
+		slave = of_property_read_bool(pdev->dev.of_node,
+						"allo,slave");
+
+		mute_gpio = devm_gpiod_get_optional(&pdev->dev, "mute",
+							GPIOD_OUT_LOW);
+		if (IS_ERR(mute_gpio)) {
+			ret = PTR_ERR(mute_gpio);
+			dev_err(&pdev->dev,
+				"failed to get mute gpio: %d\n", ret);
+			return ret;
+		}
+
+		if (mute_gpio)
+			snd_allo_boss.set_bias_level =
+				snd_allo_boss_set_bias_level;
+
+		ret = snd_soc_register_card(&snd_allo_boss);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"snd_soc_register_card() failed: %d\n", ret);
+			return ret;
+		}
+
+		if (mute_gpio)
+			snd_allo_boss_gpio_mute(&snd_allo_boss);
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int snd_allo_boss_remove(struct platform_device *pdev)
+{
+	snd_allo_boss_gpio_mute(&snd_allo_boss);
+	return snd_soc_unregister_card(&snd_allo_boss);
+}
+
+static const struct of_device_id snd_allo_boss_of_match[] = {
+	{ .compatible = "allo,boss-dac", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, snd_allo_boss_of_match);
+
+static struct platform_driver snd_allo_boss_driver = {
+	.driver = {
+		.name   = "snd-allo-boss-dac",
+		.owner  = THIS_MODULE,
+		.of_match_table = snd_allo_boss_of_match,
+	},
+	.probe          = snd_allo_boss_probe,
+	.remove         = snd_allo_boss_remove,
+};
+
+module_platform_driver(snd_allo_boss_driver);
+
+MODULE_AUTHOR("Baswaraj K <jaikumar@cem-solutions.net>");
+MODULE_DESCRIPTION("ALSA ASoC Machine Driver for Allo Boss DAC");
+MODULE_LICENSE("GPL v2");