xref: /openbmc/linux/sound/soc/soc-utils.c (revision 9cfc5c90)
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 	/* Random values to keep userspace happy when checking constraints */
63 	.info			= SNDRV_PCM_INFO_INTERLEAVED |
64 				  SNDRV_PCM_INFO_BLOCK_TRANSFER,
65 	.buffer_bytes_max	= 128*1024,
66 	.period_bytes_min	= PAGE_SIZE,
67 	.period_bytes_max	= PAGE_SIZE*2,
68 	.periods_min		= 2,
69 	.periods_max		= 128,
70 };
71 
72 static int dummy_dma_open(struct snd_pcm_substream *substream)
73 {
74 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
75 
76 	/* BE's dont need dummy params */
77 	if (!rtd->dai_link->no_pcm)
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 struct snd_soc_codec_driver dummy_codec;
93 
94 #define STUB_RATES	SNDRV_PCM_RATE_8000_192000
95 #define STUB_FORMATS	(SNDRV_PCM_FMTBIT_S8 | \
96 			SNDRV_PCM_FMTBIT_U8 | \
97 			SNDRV_PCM_FMTBIT_S16_LE | \
98 			SNDRV_PCM_FMTBIT_U16_LE | \
99 			SNDRV_PCM_FMTBIT_S24_LE | \
100 			SNDRV_PCM_FMTBIT_U24_LE | \
101 			SNDRV_PCM_FMTBIT_S32_LE | \
102 			SNDRV_PCM_FMTBIT_U32_LE | \
103 			SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
104 /*
105  * The dummy CODEC is only meant to be used in situations where there is no
106  * actual hardware.
107  *
108  * If there is actual hardware even if it does not have a control bus
109  * the hardware will still have constraints like supported samplerates, etc.
110  * which should be modelled. And the data flow graph also should be modelled
111  * using DAPM.
112  */
113 static struct snd_soc_dai_driver dummy_dai = {
114 	.name = "snd-soc-dummy-dai",
115 	.playback = {
116 		.stream_name	= "Playback",
117 		.channels_min	= 1,
118 		.channels_max	= 384,
119 		.rates		= STUB_RATES,
120 		.formats	= STUB_FORMATS,
121 	},
122 	.capture = {
123 		.stream_name	= "Capture",
124 		.channels_min	= 1,
125 		.channels_max	= 384,
126 		.rates = STUB_RATES,
127 		.formats = STUB_FORMATS,
128 	 },
129 };
130 
131 int snd_soc_dai_is_dummy(struct snd_soc_dai *dai)
132 {
133 	if (dai->driver == &dummy_dai)
134 		return 1;
135 	return 0;
136 }
137 
138 static int snd_soc_dummy_probe(struct platform_device *pdev)
139 {
140 	int ret;
141 
142 	ret = snd_soc_register_codec(&pdev->dev, &dummy_codec, &dummy_dai, 1);
143 	if (ret < 0)
144 		return ret;
145 
146 	ret = snd_soc_register_platform(&pdev->dev, &dummy_platform);
147 	if (ret < 0) {
148 		snd_soc_unregister_codec(&pdev->dev);
149 		return ret;
150 	}
151 
152 	return ret;
153 }
154 
155 static int snd_soc_dummy_remove(struct platform_device *pdev)
156 {
157 	snd_soc_unregister_platform(&pdev->dev);
158 	snd_soc_unregister_codec(&pdev->dev);
159 
160 	return 0;
161 }
162 
163 static struct platform_driver soc_dummy_driver = {
164 	.driver = {
165 		.name = "snd-soc-dummy",
166 	},
167 	.probe = snd_soc_dummy_probe,
168 	.remove = snd_soc_dummy_remove,
169 };
170 
171 static struct platform_device *soc_dummy_dev;
172 
173 int __init snd_soc_util_init(void)
174 {
175 	int ret;
176 
177 	soc_dummy_dev =
178 		platform_device_register_simple("snd-soc-dummy", -1, NULL, 0);
179 	if (IS_ERR(soc_dummy_dev))
180 		return PTR_ERR(soc_dummy_dev);
181 
182 	ret = platform_driver_register(&soc_dummy_driver);
183 	if (ret != 0)
184 		platform_device_unregister(soc_dummy_dev);
185 
186 	return ret;
187 }
188 
189 void __exit snd_soc_util_exit(void)
190 {
191 	platform_device_unregister(soc_dummy_dev);
192 	platform_driver_unregister(&soc_dummy_driver);
193 }
194