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 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 struct snd_soc_card storm_soc_card = { 73 .name = "ipq806x-storm", 74 .dev = NULL, 75 }; 76 77 static int storm_parse_of(struct snd_soc_card *card) 78 { 79 struct snd_soc_dai_link *dai_link = card->dai_link; 80 struct device_node *np = card->dev->of_node; 81 82 dai_link->cpu_of_node = of_parse_phandle(np, "cpu", 0); 83 if (!dai_link->cpu_of_node) { 84 dev_err(card->dev, "%s() error getting cpu phandle\n", 85 __func__); 86 return -EINVAL; 87 } 88 dai_link->platform_of_node = dai_link->cpu_of_node; 89 90 dai_link->codec_of_node = of_parse_phandle(np, "codec", 0); 91 if (!dai_link->codec_of_node) { 92 dev_err(card->dev, "%s() error getting codec phandle\n", 93 __func__); 94 return -EINVAL; 95 } 96 97 return 0; 98 } 99 100 static int storm_platform_probe(struct platform_device *pdev) 101 { 102 struct snd_soc_card *card = &storm_soc_card; 103 int ret; 104 105 if (card->dev) { 106 dev_err(&pdev->dev, "%s() error, existing soundcard\n", 107 __func__); 108 return -ENODEV; 109 } 110 card->dev = &pdev->dev; 111 platform_set_drvdata(pdev, card); 112 113 ret = snd_soc_of_parse_card_name(card, "qcom,model"); 114 if (ret) { 115 dev_err(&pdev->dev, "%s() error parsing card name: %d\n", 116 __func__, ret); 117 return ret; 118 } 119 120 card->dai_link = &storm_dai_link; 121 card->num_links = 1; 122 123 ret = storm_parse_of(card); 124 if (ret) { 125 dev_err(&pdev->dev, "%s() error resolving dai links: %d\n", 126 __func__, ret); 127 return ret; 128 } 129 130 ret = devm_snd_soc_register_card(&pdev->dev, card); 131 if (ret == -EPROBE_DEFER) { 132 card->dev = NULL; 133 return ret; 134 } else if (ret) { 135 dev_err(&pdev->dev, "%s() error registering soundcard: %d\n", 136 __func__, ret); 137 return ret; 138 } 139 140 return 0; 141 } 142 143 #ifdef CONFIG_OF 144 static const struct of_device_id storm_device_id[] = { 145 { .compatible = "google,storm-audio" }, 146 {}, 147 }; 148 MODULE_DEVICE_TABLE(of, storm_device_id); 149 #endif 150 151 static struct platform_driver storm_platform_driver = { 152 .driver = { 153 .name = "storm-audio", 154 .of_match_table = 155 of_match_ptr(storm_device_id), 156 }, 157 .probe = storm_platform_probe, 158 }; 159 module_platform_driver(storm_platform_driver); 160 161 MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver"); 162 MODULE_LICENSE("GPL v2"); 163