LXR linux/sound/soc/qcom/storm.c

   1/*
   2 * Copyright (c) 2010-2011,2013-2015 The Linux Foundation. All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 and
   6 * only version 2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 *
  13 * storm.c -- ALSA SoC machine driver for QTi ipq806x-based Storm board
  14 */
  15
  16#include <linux/device.h>
  17#include <linux/module.h>
  18#include <linux/of.h>
  19#include <linux/mod_devicetable.h>
  20#include <linux/platform_device.h>
  21#include <sound/pcm.h>
  22#include <sound/pcm_params.h>
  23#include <sound/soc.h>
  24
  25#define STORM_SYSCLK_MULT                       4
  26
  27static int storm_ops_hw_params(struct snd_pcm_substream *substream,
  28                struct snd_pcm_hw_params *params)
  29{
  30        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
  31        struct snd_soc_card *card = soc_runtime->card;
  32        snd_pcm_format_t format = params_format(params);
  33        unsigned int rate = params_rate(params);
  34        unsigned int sysclk_freq;
  35        int bitwidth, ret;
  36
  37        bitwidth = snd_pcm_format_width(format);
  38        if (bitwidth < 0) {
  39                dev_err(card->dev, "invalid bit width given: %d\n", bitwidth);
  40                return bitwidth;
  41        }
  42
  43        /*
  44         * as the CPU DAI is the I2S bus master and no system clock is needed by
  45         * the MAX98357a DAC, simply set the system clock to be a constant
  46         * multiple of the bit clock for the clock divider
  47         */
  48        sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;
  49
  50        ret = snd_soc_dai_set_sysclk(soc_runtime->cpu_dai, 0, sysclk_freq, 0);
  51        if (ret) {
  52                dev_err(card->dev, "error setting sysclk to %u: %d\n",
  53                        sysclk_freq, ret);
  54                return ret;
  55        }
  56
  57        return 0;
  58}
  59
  60static const struct snd_soc_ops storm_soc_ops = {
  61        .hw_params      = storm_ops_hw_params,
  62};
  63
  64static struct snd_soc_dai_link storm_dai_link = {
  65        .name           = "Primary",
  66        .stream_name    = "Primary",
  67        .codec_dai_name = "HiFi",
  68        .ops            = &storm_soc_ops,
  69};
  70
  71static int storm_parse_of(struct snd_soc_card *card)
  72{
  73        struct snd_soc_dai_link *dai_link = card->dai_link;
  74        struct device_node *np = card->dev->of_node;
  75
  76        dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0);
  77        if (!dai_link->cpu_of_node) {
  78                dev_err(card->dev, "error getting cpu phandle\n");
  79                return -EINVAL;
  80        }
  81        dai_link->platform_of_node = dai_link->cpu_of_node;
  82
  83        dai_link->codec_of_node = of_parse_phandle(np, "codec", 0);
  84        if (!dai_link->codec_of_node) {
  85                dev_err(card->dev, "error getting codec phandle\n");
  86                return -EINVAL;
  87        }
  88
  89        return 0;
  90}
  91
  92static int storm_platform_probe(struct platform_device *pdev)
  93{
  94        struct snd_soc_card *card;
  95        int ret;
  96
  97        card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
  98        if (!card)
  99                return -ENOMEM;
 100
 101        card->dev = &pdev->dev;
 102        platform_set_drvdata(pdev, card);
 103
 104        ret = snd_soc_of_parse_card_name(card, "qcom,model");
 105        if (ret) {
 106                dev_err(&pdev->dev, "error parsing card name: %d\n", ret);
 107                return ret;
 108        }
 109
 110        card->dai_link  = &storm_dai_link;
 111        card->num_links = 1;
 112
 113        ret = storm_parse_of(card);
 114        if (ret) {
 115                dev_err(&pdev->dev, "error resolving dai links: %d\n", ret);
 116                return ret;
 117        }
 118
 119        ret = devm_snd_soc_register_card(&pdev->dev, card);
 120        if (ret)
 121                dev_err(&pdev->dev, "error registering soundcard: %d\n", ret);
 122
 123        return ret;
 124
 125}
 126
 127#ifdef CONFIG_OF
 128static const struct of_device_id storm_device_id[]  = {
 129        { .compatible = "google,storm-audio" },
 130        {},
 131};
 132MODULE_DEVICE_TABLE(of, storm_device_id);
 133#endif
 134
 135static struct platform_driver storm_platform_driver = {
 136        .driver = {
 137                .name = "storm-audio",
 138                .of_match_table =
 139                        of_match_ptr(storm_device_id),
 140        },
 141        .probe = storm_platform_probe,
 142};
 143module_platform_driver(storm_platform_driver);
 144
 145MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
 146MODULE_LICENSE("GPL v2");
 147