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
  27 static 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
  61 static const struct snd_soc_ops storm_soc_ops = {
  62         .hw_params      = storm_ops_hw_params,
  63 };
  64
  65 static 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
  72 static 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
  95 static 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
 134 static const struct of_device_id storm_device_id[]  = {
 135         { .compatible = "google,storm-audio" },
 136         {},
 137 };
 138 MODULE_DEVICE_TABLE(of, storm_device_id);
 139 #endif
 140
 141 static 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 };
 149 module_platform_driver(storm_platform_driver);
 150
 151 MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver");
 152 MODULE_LICENSE("GPL v2");