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, "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 60 static const struct snd_soc_ops storm_soc_ops = { 61 .hw_params = storm_ops_hw_params, 62 }; 63 64 static 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 71 static 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 92 static 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 128 static const struct of_device_id storm_device_id[] = { 129 { .compatible = "google,storm-audio" }, 130 {}, 131 }; 132 MODULE_DEVICE_TABLE(of, storm_device_id); 133 #endif 134 135 static 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 }; 143 module_platform_driver(storm_platform_driver); 144 145 MODULE_DESCRIPTION("QTi IPQ806x-based Storm Machine Driver"); 146 MODULE_LICENSE("GPL v2"); 147