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, "%s() invalid bit width given: %d\n",
  40                                __func__, bitwidth);
  41                return bitwidth;
  42        }
  43
  44        /*
  45         * as the CPU DAI is the I2S bus master and no system clock is needed by
  46         * the MAX98357a DAC, simply set the system clock to be a constant
  47         * multiple of the bit clock for the clock divider
  48         */
  49        sysclk_freq = rate * bitwidth * 2 * STORM_SYSCLK_MULT;
  50
  51        ret = snd_soc_dai_set_sysclk(soc_runtime->cpu_dai, 0, sysclk_freq, 0);
  52        if (ret) {
  53                dev_err(card->dev, "%s() error setting sysclk to %u: %d\n",
  54                                __func__, sysclk_freq, ret);
  55                return ret;
  56        }
  57
  58        return 0;
  59}
  60
  61static struct snd_soc_ops storm_soc_ops = {
  62        .hw_params      = storm_ops_hw_params,
  63};
  64
  65static struct snd_soc_dai_link storm_dai_link = {
  66        .name           = "Primary",
  67        .stream_name    = "Primary",
  68        .codec_dai_name = "HiFi",
  69        .ops            = &storm_soc_ops,
  70};
  71
  72static int storm_parse_of(struct snd_soc_card *card)
  73{
  74        struct snd_soc_dai_link *dai_link = card->dai_link;
  75        struct device_node *np = card->dev->of_node;
  76
  77        dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0);
  78        if (!dai_link->cpu_of_node) {
  79                dev_err(card->dev, "%s() error getting cpu phandle\n",
  80                                __func__);
  81                return -EINVAL;
  82        }
  83        dai_link->platform_of_node = dai_link->cpu_of_node;
  84
  85        dai_link->codec_of_node = of_parse_phandle(np, "codec", 0);
  86        if (!dai_link->codec_of_node) {
  87                dev_err(card->dev, "%s() error getting codec phandle\n",
  88                                __func__);
  89                return -EINVAL;
  90        }
  91
  92        return 0;
  93}
  94
  95static int storm_platform_probe(struct platform_device *pdev)
  96{
  97        struct snd_soc_card *card;
  98        int ret;
  99
 100        card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
 101        if (!card)
 102                return -ENOMEM;
 103
 104        card->dev = &pdev->dev;
 105        platform_set_drvdata(pdev, card);
 106
 107        ret = snd_soc_of_parse_card_name(card, "qcom,model");
 108        if (ret) {
 109                dev_err(&pdev->dev, "%s() error parsing card name: %d\n",
 110                                __func__, ret);
 111                return ret;
 112        }
 113
 114        card->dai_link  = &storm_dai_link;
 115        card->num_links = 1;
 116
 117        ret = storm_parse_of(card);
 118        if (ret) {
 119                dev_err(&pdev->dev, "%s() error resolving dai links: %d\n",
 120                                __func__, ret);
 121                return ret;
 122        }
 123
 124        ret = devm_snd_soc_register_card(&pdev->dev, card);
 125        if (ret)
 126                dev_err(&pdev->dev, "%s() error registering soundcard: %d\n",
 127                                __func__, ret);
 128
 129        return ret;
 130
 131}
 132
 133#ifdef CONFIG_OF
 134static const struct of_device_id storm_device_id[]  = {
 135        { .compatible = "google,storm-audio" },
 136        {},
 137};
 138MODULE_DEVICE_TABLE(of, storm_device_id);
 139#endif
 140
 141static struct platform_driver storm_platform_driver = {
 142        .driver = {
 143                .name = "storm-audio",
 144                .of_match_table =
 145                        of_match_ptr(storm_device_id),
 146        },
 147        .probe = storm_platform_probe,
 148};
 149module_platform_driver(storm_platform_driver);
 150
 151MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
 152MODULE_LICENSE("GPL v2");
 153