1 /* 2 * soc-util.c -- ALSA SoC Audio Layer utility functions 3 * 4 * Copyright 2009 Wolfson Microelectronics PLC. 5 * 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 7 * Liam Girdwood <lrg@slimlogic.co.uk> 8 * 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the 12 * Free Software Foundation; either version 2 of the License, or (at your 13 * option) any later version. 14 */ 15 16 #include <linux/platform_device.h> 17 #include <linux/export.h> 18 #include <sound/core.h> 19 #include <sound/pcm.h> 20 #include <sound/pcm_params.h> 21 #include <sound/soc.h> 22 23 int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots) 24 { 25 return sample_size * channels * tdm_slots; 26 } 27 EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size); 28 29 int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params) 30 { 31 int sample_size; 32 33 sample_size = snd_pcm_format_width(params_format(params)); 34 if (sample_size < 0) 35 return sample_size; 36 37 return snd_soc_calc_frame_size(sample_size, params_channels(params), 38 1); 39 } 40 EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size); 41 42 int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots) 43 { 44 return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots); 45 } 46 EXPORT_SYMBOL_GPL(snd_soc_calc_bclk); 47 48 int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params) 49 { 50 int ret; 51 52 ret = snd_soc_params_to_frame_size(params); 53 54 if (ret > 0) 55 return ret * params_rate(params); 56 else 57 return ret; 58 } 59 EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk); 60 61 static const struct snd_pcm_hardware dummy_dma_hardware = { 62 .formats = 0xffffffff, 63 .channels_min = 1, 64 .channels_max = UINT_MAX, 65 66 /* Random values to keep userspace happy when checking constraints */ 67 .info = SNDRV_PCM_INFO_INTERLEAVED | 68 SNDRV_PCM_INFO_BLOCK_TRANSFER, 69 .buffer_bytes_max = 128*1024, 70 .period_bytes_min = PAGE_SIZE, 71 .period_bytes_max = PAGE_SIZE*2, 72 .periods_min = 2, 73 .periods_max = 128, 74 }; 75 76 static int dummy_dma_open(struct snd_pcm_substream *substream) 77 { 78 snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware); 79 80 return 0; 81 } 82 83 static struct snd_pcm_ops dummy_dma_ops = { 84 .open = dummy_dma_open, 85 .ioctl = snd_pcm_lib_ioctl, 86 }; 87 88 static struct snd_soc_platform_driver dummy_platform = { 89 .ops = &dummy_dma_ops, 90 }; 91 92 static __devinit int snd_soc_dummy_probe(struct platform_device *pdev) 93 { 94 return snd_soc_register_platform(&pdev->dev, &dummy_platform); 95 } 96 97 static __devexit int snd_soc_dummy_remove(struct platform_device *pdev) 98 { 99 snd_soc_unregister_platform(&pdev->dev); 100 101 return 0; 102 } 103 104 static struct platform_driver soc_dummy_driver = { 105 .driver = { 106 .name = "snd-soc-dummy", 107 .owner = THIS_MODULE, 108 }, 109 .probe = snd_soc_dummy_probe, 110 .remove = __devexit_p(snd_soc_dummy_remove), 111 }; 112 113 static struct platform_device *soc_dummy_dev; 114 115 int __init snd_soc_util_init(void) 116 { 117 int ret; 118 119 soc_dummy_dev = platform_device_alloc("snd-soc-dummy", -1); 120 if (!soc_dummy_dev) 121 return -ENOMEM; 122 123 ret = platform_device_add(soc_dummy_dev); 124 if (ret != 0) { 125 platform_device_put(soc_dummy_dev); 126 return ret; 127 } 128 129 ret = platform_driver_register(&soc_dummy_driver); 130 if (ret != 0) 131 platform_device_unregister(soc_dummy_dev); 132 133 return ret; 134 } 135 136 void __exit snd_soc_util_exit(void) 137 { 138 platform_device_unregister(soc_dummy_dev); 139 platform_driver_unregister(&soc_dummy_driver); 140 } 141