1// SPDX-License-Identifier: GPL-2.0+
2//
3// soc-util.c -- ALSA SoC Audio Layer utility functions
4//
5// Copyright 2009 Wolfson Microelectronics PLC.
6//
7// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8// Liam Girdwood <lrg@slimlogic.co.uk>
9
10#include <linux/platform_device.h>
11#include <linux/export.h>
12#include <linux/math.h>
13#include <sound/core.h>
14#include <sound/pcm.h>
15#include <sound/pcm_params.h>
16#include <sound/soc.h>
17
18int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
19{
20 return sample_size * channels * tdm_slots;
21}
22EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
23
24int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params)
25{
26 int sample_size;
27
28 sample_size = snd_pcm_format_width(format: params_format(p: params));
29 if (sample_size < 0)
30 return sample_size;
31
32 return snd_soc_calc_frame_size(sample_size, params_channels(p: params),
33 1);
34}
35EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
36
37int snd_soc_calc_bclk(int fs, int sample_size, int channels, int tdm_slots)
38{
39 return fs * snd_soc_calc_frame_size(sample_size, channels, tdm_slots);
40}
41EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
42
43int snd_soc_params_to_bclk(struct snd_pcm_hw_params *params)
44{
45 int ret;
46
47 ret = snd_soc_params_to_frame_size(params);
48
49 if (ret > 0)
50 return ret * params_rate(p: params);
51 else
52 return ret;
53}
54EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk);
55
56/**
57 * snd_soc_tdm_params_to_bclk - calculate bclk from params and tdm slot info.
58 *
59 * Calculate the bclk from the params sample rate, the tdm slot count and the
60 * tdm slot width. Optionally round-up the slot count to a given multiple.
61 * Either or both of tdm_width and tdm_slots can be 0.
62 *
63 * If tdm_width == 0: use params_width() as the slot width.
64 * If tdm_slots == 0: use params_channels() as the slot count.
65 *
66 * If slot_multiple > 1 the slot count (or params_channels() if tdm_slots == 0)
67 * will be rounded up to a multiple of slot_multiple. This is mainly useful for
68 * I2S mode, which has a left and right phase so the number of slots is always
69 * a multiple of 2.
70 *
71 * If tdm_width == 0 && tdm_slots == 0 && slot_multiple < 2, this is equivalent
72 * to calling snd_soc_params_to_bclk().
73 *
74 * @params: Pointer to struct_pcm_hw_params.
75 * @tdm_width: Width in bits of the tdm slots. Must be >= 0.
76 * @tdm_slots: Number of tdm slots per frame. Must be >= 0.
77 * @slot_multiple: If >1 roundup slot count to a multiple of this value.
78 *
79 * Return: bclk frequency in Hz, else a negative error code if params format
80 * is invalid.
81 */
82int snd_soc_tdm_params_to_bclk(struct snd_pcm_hw_params *params,
83 int tdm_width, int tdm_slots, int slot_multiple)
84{
85 if (!tdm_slots)
86 tdm_slots = params_channels(p: params);
87
88 if (slot_multiple > 1)
89 tdm_slots = roundup(tdm_slots, slot_multiple);
90
91 if (!tdm_width) {
92 tdm_width = snd_pcm_format_width(format: params_format(p: params));
93 if (tdm_width < 0)
94 return tdm_width;
95 }
96
97 return snd_soc_calc_bclk(params_rate(p: params), tdm_width, 1, tdm_slots);
98}
99EXPORT_SYMBOL_GPL(snd_soc_tdm_params_to_bclk);
100
101static const struct snd_pcm_hardware dummy_dma_hardware = {
102 /* Random values to keep userspace happy when checking constraints */
103 .info = SNDRV_PCM_INFO_INTERLEAVED |
104 SNDRV_PCM_INFO_BLOCK_TRANSFER,
105 .buffer_bytes_max = 128*1024,
106 .period_bytes_min = PAGE_SIZE,
107 .period_bytes_max = PAGE_SIZE*2,
108 .periods_min = 2,
109 .periods_max = 128,
110};
111
112
113static const struct snd_soc_component_driver dummy_platform;
114
115static int dummy_dma_open(struct snd_soc_component *component,
116 struct snd_pcm_substream *substream)
117{
118 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
119 int i;
120
121 /*
122 * If there are other components associated with rtd, we shouldn't
123 * override their hwparams
124 */
125 for_each_rtd_components(rtd, i, component) {
126 if (component->driver == &dummy_platform)
127 return 0;
128 }
129
130 /* BE's dont need dummy params */
131 if (!rtd->dai_link->no_pcm)
132 snd_soc_set_runtime_hwparams(substream, hw: &dummy_dma_hardware);
133
134 return 0;
135}
136
137static const struct snd_soc_component_driver dummy_platform = {
138 .open = dummy_dma_open,
139};
140
141static const struct snd_soc_component_driver dummy_codec = {
142 .idle_bias_on = 1,
143 .use_pmdown_time = 1,
144 .endianness = 1,
145};
146
147#define STUB_RATES SNDRV_PCM_RATE_8000_384000
148#define STUB_FORMATS (SNDRV_PCM_FMTBIT_S8 | \
149 SNDRV_PCM_FMTBIT_U8 | \
150 SNDRV_PCM_FMTBIT_S16_LE | \
151 SNDRV_PCM_FMTBIT_U16_LE | \
152 SNDRV_PCM_FMTBIT_S24_LE | \
153 SNDRV_PCM_FMTBIT_S24_3LE | \
154 SNDRV_PCM_FMTBIT_U24_LE | \
155 SNDRV_PCM_FMTBIT_S32_LE | \
156 SNDRV_PCM_FMTBIT_U32_LE | \
157 SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
158
159/*
160 * Select these from Sound Card Manually
161 * SND_SOC_POSSIBLE_DAIFMT_CBP_CFP
162 * SND_SOC_POSSIBLE_DAIFMT_CBP_CFC
163 * SND_SOC_POSSIBLE_DAIFMT_CBC_CFP
164 * SND_SOC_POSSIBLE_DAIFMT_CBC_CFC
165 */
166static u64 dummy_dai_formats =
167 SND_SOC_POSSIBLE_DAIFMT_I2S |
168 SND_SOC_POSSIBLE_DAIFMT_RIGHT_J |
169 SND_SOC_POSSIBLE_DAIFMT_LEFT_J |
170 SND_SOC_POSSIBLE_DAIFMT_DSP_A |
171 SND_SOC_POSSIBLE_DAIFMT_DSP_B |
172 SND_SOC_POSSIBLE_DAIFMT_AC97 |
173 SND_SOC_POSSIBLE_DAIFMT_PDM |
174 SND_SOC_POSSIBLE_DAIFMT_GATED |
175 SND_SOC_POSSIBLE_DAIFMT_CONT |
176 SND_SOC_POSSIBLE_DAIFMT_NB_NF |
177 SND_SOC_POSSIBLE_DAIFMT_NB_IF |
178 SND_SOC_POSSIBLE_DAIFMT_IB_NF |
179 SND_SOC_POSSIBLE_DAIFMT_IB_IF;
180
181static const struct snd_soc_dai_ops dummy_dai_ops = {
182 .auto_selectable_formats = &dummy_dai_formats,
183 .num_auto_selectable_formats = 1,
184};
185
186/*
187 * The dummy CODEC is only meant to be used in situations where there is no
188 * actual hardware.
189 *
190 * If there is actual hardware even if it does not have a control bus
191 * the hardware will still have constraints like supported samplerates, etc.
192 * which should be modelled. And the data flow graph also should be modelled
193 * using DAPM.
194 */
195static struct snd_soc_dai_driver dummy_dai = {
196 .name = "snd-soc-dummy-dai",
197 .playback = {
198 .stream_name = "Playback",
199 .channels_min = 1,
200 .channels_max = 384,
201 .rates = STUB_RATES,
202 .formats = STUB_FORMATS,
203 },
204 .capture = {
205 .stream_name = "Capture",
206 .channels_min = 1,
207 .channels_max = 384,
208 .rates = STUB_RATES,
209 .formats = STUB_FORMATS,
210 },
211 .ops = &dummy_dai_ops,
212};
213
214int snd_soc_dai_is_dummy(struct snd_soc_dai *dai)
215{
216 if (dai->driver == &dummy_dai)
217 return 1;
218 return 0;
219}
220EXPORT_SYMBOL_GPL(snd_soc_dai_is_dummy);
221
222int snd_soc_component_is_dummy(struct snd_soc_component *component)
223{
224 return ((component->driver == &dummy_platform) ||
225 (component->driver == &dummy_codec));
226}
227
228struct snd_soc_dai_link_component snd_soc_dummy_dlc = {
229 .of_node = NULL,
230 .dai_name = "snd-soc-dummy-dai",
231 .name = "snd-soc-dummy",
232};
233EXPORT_SYMBOL_GPL(snd_soc_dummy_dlc);
234
235static int snd_soc_dummy_probe(struct platform_device *pdev)
236{
237 int ret;
238
239 ret = devm_snd_soc_register_component(dev: &pdev->dev,
240 component_driver: &dummy_codec, dai_drv: &dummy_dai, num_dai: 1);
241 if (ret < 0)
242 return ret;
243
244 ret = devm_snd_soc_register_component(dev: &pdev->dev, component_driver: &dummy_platform,
245 NULL, num_dai: 0);
246
247 return ret;
248}
249
250static struct platform_driver soc_dummy_driver = {
251 .driver = {
252 .name = "snd-soc-dummy",
253 },
254 .probe = snd_soc_dummy_probe,
255};
256
257static struct platform_device *soc_dummy_dev;
258
259int __init snd_soc_util_init(void)
260{
261 int ret;
262
263 soc_dummy_dev =
264 platform_device_register_simple(name: "snd-soc-dummy", id: -1, NULL, num: 0);
265 if (IS_ERR(ptr: soc_dummy_dev))
266 return PTR_ERR(ptr: soc_dummy_dev);
267
268 ret = platform_driver_register(&soc_dummy_driver);
269 if (ret != 0)
270 platform_device_unregister(soc_dummy_dev);
271
272 return ret;
273}
274
275void snd_soc_util_exit(void)
276{
277 platform_driver_unregister(&soc_dummy_driver);
278 platform_device_unregister(soc_dummy_dev);
279}
280

source code of linux/sound/soc/soc-utils.c