1/*
  2 * SoC audio for EDB93xx
  3 *
  4 * Copyright (c) 2010 Alexander Sverdlin <subaparts@yandex.ru>
  5 *
  6 * This program is free software; you can redistribute it and/or
  7 * modify it under the terms of the GNU General Public License
  8 * as published by the Free Software Foundation; either version 2
  9 * of the License, or (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * This driver support CS4271 codec being master or slave, working
 17 * in control port mode, connected either via SPI or I2C.
 18 * The data format accepted is I2S or left-justified.
 19 * DAPM support not implemented.
 20 */
 21
 22#include <linux/platform_device.h>
 23#include <linux/gpio.h>
 24#include <linux/module.h>
 25#include <sound/core.h>
 26#include <sound/pcm.h>
 27#include <sound/soc.h>
 28#include <asm/mach-types.h>
 29#include <mach/hardware.h>
 30
 31static int edb93xx_hw_params(struct snd_pcm_substream *substream,
 32			     struct snd_pcm_hw_params *params)
 33{
 34	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 35	struct snd_soc_dai *codec_dai = rtd->codec_dai;
 36	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 37	int err;
 38	unsigned int mclk_rate;
 39	unsigned int rate = params_rate(params);
 40
 41	/*
 42	 * According to CS4271 datasheet we use MCLK/LRCK=256 for
 43	 * rates below 50kHz and 128 for higher sample rates
 44	 */
 45	if (rate < 50000)
 46		mclk_rate = rate * 64 * 4;
 47	else
 48		mclk_rate = rate * 64 * 2;
 49
 50	err = snd_soc_dai_set_sysclk(codec_dai, 0, mclk_rate,
 51				     SND_SOC_CLOCK_IN);
 52	if (err)
 53		return err;
 54
 55	return snd_soc_dai_set_sysclk(cpu_dai, 0, mclk_rate,
 56				      SND_SOC_CLOCK_OUT);
 57}
 58
 59static struct snd_soc_ops edb93xx_ops = {
 60	.hw_params	= edb93xx_hw_params,
 61};
 62
 63static struct snd_soc_dai_link edb93xx_dai = {
 64	.name		= "CS4271",
 65	.stream_name	= "CS4271 HiFi",
 66	.platform_name	= "ep93xx-i2s",
 67	.cpu_dai_name	= "ep93xx-i2s",
 68	.codec_name	= "spi0.0",
 69	.codec_dai_name	= "cs4271-hifi",
 70	.dai_fmt	= SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_IF |
 71			  SND_SOC_DAIFMT_CBS_CFS,
 72	.ops		= &edb93xx_ops,
 73};
 74
 75static struct snd_soc_card snd_soc_edb93xx = {
 76	.name		= "EDB93XX",
 77	.owner		= THIS_MODULE,
 78	.dai_link	= &edb93xx_dai,
 79	.num_links	= 1,
 80};
 81
 82static int edb93xx_probe(struct platform_device *pdev)
 83{
 84	struct snd_soc_card *card = &snd_soc_edb93xx;
 85	int ret;
 86
 87	ret = ep93xx_i2s_acquire();
 88	if (ret)
 89		return ret;
 90
 91	card->dev = &pdev->dev;
 92
 93	ret = snd_soc_register_card(card);
 94	if (ret) {
 95		dev_err(&pdev->dev, "snd_soc_register_card() failed: %d\n",
 96			ret);
 97		ep93xx_i2s_release();
 98	}
 99
100	return ret;
101}
102
103static int edb93xx_remove(struct platform_device *pdev)
104{
105	struct snd_soc_card *card = platform_get_drvdata(pdev);
106
107	snd_soc_unregister_card(card);
108	ep93xx_i2s_release();
109
110	return 0;
111}
112
113static struct platform_driver edb93xx_driver = {
114	.driver		= {
115		.name	= "edb93xx-audio",
116	},
117	.probe		= edb93xx_probe,
118	.remove		= edb93xx_remove,
119};
120
121module_platform_driver(edb93xx_driver);
122
123MODULE_AUTHOR("Alexander Sverdlin <subaparts@yandex.ru>");
124MODULE_DESCRIPTION("ALSA SoC EDB93xx");
125MODULE_LICENSE("GPL");
126MODULE_ALIAS("platform:edb93xx-audio");