ASoC: qcom: Add Storm machine driver

/*

 * Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 and

 * only 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.

 *

 * storm.c -- ALSA SoC machine driver for QTi ipq806x-based Storm board

 */

#include <linux/device.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/mod_devicetable.h>

#include <linux/platform_device.h>

#include <sound/pcm.h>

#include <sound/pcm_params.h>

#include <sound/soc.h>

#define STORM_SYSCLK_MULT			4

static int storm_ops_hw_params(struct snd_pcm_substream *substream,

		struct snd_pcm_hw_params *params)

{

	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;

	struct snd_soc_card *card = soc_runtime->card;

	snd_pcm_format_t format = params_format(params);

	unsigned int rate = params_rate(params);

	unsigned int sysclk_freq;

	int bitwidth, ret;

	bitwidth = snd_pcm_format_width(format);

	if (bitwidth < 0) {

		dev_err(card->dev, "%s() invalid bit width given: %d\n",

				__func__, bitwidth);

		return bitwidth;

	}

	/*

	 * as the CPU DAI is the I2S bus master and no system clock is needed by

	 * the MAX98357a DAC, simply set the system clock to be a constant

	 * multiple of the bit clock for the clock divider

	 */

	sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;

	ret = snd_soc_dai_set_sysclk(soc_runtime->cpu_dai, 0, sysclk_freq, 0);

	if (ret) {

		dev_err(card->dev, "%s() error setting sysclk to %u: %d\n",

				__func__, sysclk_freq, ret);

		return ret;

	}

	return 0;

}

static struct snd_soc_ops storm_soc_ops = {

	.hw_params	= storm_ops_hw_params,

};

static struct snd_soc_dai_link storm_dai_link = {

	.name		= "Primary",

	.stream_name	= "Primary",

	.codec_dai_name	= "HiFi",

	.ops		= &storm_soc_ops,

};

static struct snd_soc_card storm_soc_card = {

	.name	= "ipq806x-storm",

	.dev	= NULL,

};

static int storm_parse_of(struct snd_soc_card *card)

{

	struct snd_soc_dai_link *dai_link = card->dai_link;

	struct device_node *np = card->dev->of_node;

	dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0);

	if (!dai_link->cpu_of_node) {

		dev_err(card->dev, "%s() error getting cpu phandle\n",

				__func__);

		return -EINVAL;

	}

	dai_link->platform_of_node = dai_link->cpu_of_node;

	dai_link->codec_of_node = of_parse_phandle(np, "codec", 0);

	if (!dai_link->codec_of_node) {

		dev_err(card->dev, "%s() error getting codec phandle\n",

				__func__);

		return -EINVAL;

	}

	return 0;

}

static int storm_platform_probe(struct platform_device *pdev)

{

	struct snd_soc_card *card = &storm_soc_card;

	int ret;

	if (card->dev) {

		dev_err(&pdev->dev, "%s() error, existing soundcard\n",

				__func__);

		return -ENODEV;

	}

	card->dev = &pdev->dev;

	platform_set_drvdata(pdev, card);

	ret = snd_soc_of_parse_card_name(card, "qcom,model");

	if (ret) {

		dev_err(&pdev->dev, "%s() error parsing card name: %d\n",

				__func__, ret);

		return ret;

	}

	card->dai_link	= &storm_dai_link;

	card->num_links	= 1;

	ret = storm_parse_of(card);

	if (ret) {

		dev_err(&pdev->dev, "%s() error resolving dai links: %d\n",

				__func__, ret);

		return ret;

	}

	ret = devm_snd_soc_register_card(&pdev->dev, card);

	if (ret == -EPROBE_DEFER) {

		card->dev = NULL;

		return ret;

	} else if (ret) {

		dev_err(&pdev->dev, "%s() error registering soundcard: %d\n",

				__func__, ret);

		return ret;

	}

	return 0;

}

#ifdef CONFIG_OF

static const struct of_device_id storm_device_id[]  = {

	{ .compatible = "google,storm-audio" },

	{},

};

MODULE_DEVICE_TABLE(of, storm_device_id);

#endif

static struct platform_driver storm_platform_driver = {

	.driver = {

		.name = "storm-audio",

		.of_match_table =

			of_match_ptr(storm_device_id),

	},

	.probe = storm_platform_probe,

};

module_platform_driver(storm_platform_driver);

MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");

MODULE_LICENSE("GPL v2");