xref: /openbmc/linux/sound/soc/soc-utils.c (revision 12cecbf9)
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 
18 int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots)
19 {
20 	return sample_size * channels * tdm_slots;
21 }
22 EXPORT_SYMBOL_GPL(snd_soc_calc_frame_size);
23 
24 int 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(params_format(params));
29 	if (sample_size < 0)
30 		return sample_size;
31 
32 	return snd_soc_calc_frame_size(sample_size, params_channels(params),
33 				       1);
34 }
35 EXPORT_SYMBOL_GPL(snd_soc_params_to_frame_size);
36 
37 int 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 }
41 EXPORT_SYMBOL_GPL(snd_soc_calc_bclk);
42 
43 int 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(params);
51 	else
52 		return ret;
53 }
54 EXPORT_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 and the tdm slot count and
60  * tdm slot width. Either or both of tdm_width and tdm_slots can be 0.
61  *
62  * If tdm_width == 0 and tdm_slots > 0:	the params_width will be used.
63  * If tdm_width > 0 and tdm_slots == 0:	the params_channels will be used
64  *					as the slot count.
65  * Both tdm_width and tdm_slots are 0:	this is equivalent to calling
66  *					snd_soc_params_to_bclk().
67  *
68  * If slot_multiple > 1 the slot count (or params_channels if tdm_slots == 0)
69  * will be rounded up to a multiple of this value. This is mainly useful for
70  * I2S mode, which has a left and right phase so the number of slots is always
71  * a multiple of 2.
72  *
73  * @params:        Pointer to struct_pcm_hw_params.
74  * @tdm_width:     Width in bits of the tdm slots.
75  * @tdm_slots:     Number of tdm slots per frame.
76  * @slot_multiple: If >1 roundup slot count to a multiple of this value.
77  *
78  * Return: bclk frequency in Hz, else a negative error code if params format
79  *	   is invalid.
80  */
81 int snd_soc_tdm_params_to_bclk(struct snd_pcm_hw_params *params,
82 			       int tdm_width, int tdm_slots, int slot_multiple)
83 {
84 	if (!tdm_slots)
85 		tdm_slots = params_channels(params);
86 
87 	if (slot_multiple > 1)
88 		tdm_slots = roundup(tdm_slots, slot_multiple);
89 
90 	if (!tdm_width) {
91 		tdm_width = snd_pcm_format_width(params_format(params));
92 		if (tdm_width < 0)
93 			return tdm_width;
94 	}
95 
96 	return snd_soc_calc_bclk(params_rate(params), tdm_width, 1, tdm_slots);
97 }
98 EXPORT_SYMBOL_GPL(snd_soc_tdm_params_to_bclk);
99 
100 static const struct snd_pcm_hardware dummy_dma_hardware = {
101 	/* Random values to keep userspace happy when checking constraints */
102 	.info			= SNDRV_PCM_INFO_INTERLEAVED |
103 				  SNDRV_PCM_INFO_BLOCK_TRANSFER,
104 	.buffer_bytes_max	= 128*1024,
105 	.period_bytes_min	= PAGE_SIZE,
106 	.period_bytes_max	= PAGE_SIZE*2,
107 	.periods_min		= 2,
108 	.periods_max		= 128,
109 };
110 
111 
112 static const struct snd_soc_component_driver dummy_platform;
113 
114 static int dummy_dma_open(struct snd_soc_component *component,
115 			  struct snd_pcm_substream *substream)
116 {
117 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
118 	int i;
119 
120 	/*
121 	 * If there are other components associated with rtd, we shouldn't
122 	 * override their hwparams
123 	 */
124 	for_each_rtd_components(rtd, i, component) {
125 		if (component->driver == &dummy_platform)
126 			return 0;
127 	}
128 
129 	/* BE's dont need dummy params */
130 	if (!rtd->dai_link->no_pcm)
131 		snd_soc_set_runtime_hwparams(substream, &dummy_dma_hardware);
132 
133 	return 0;
134 }
135 
136 static const struct snd_soc_component_driver dummy_platform = {
137 	.open		= dummy_dma_open,
138 };
139 
140 static const struct snd_soc_component_driver dummy_codec = {
141 	.idle_bias_on		= 1,
142 	.use_pmdown_time	= 1,
143 	.endianness		= 1,
144 };
145 
146 #define STUB_RATES	SNDRV_PCM_RATE_8000_384000
147 #define STUB_FORMATS	(SNDRV_PCM_FMTBIT_S8 | \
148 			SNDRV_PCM_FMTBIT_U8 | \
149 			SNDRV_PCM_FMTBIT_S16_LE | \
150 			SNDRV_PCM_FMTBIT_U16_LE | \
151 			SNDRV_PCM_FMTBIT_S24_LE | \
152 			SNDRV_PCM_FMTBIT_S24_3LE | \
153 			SNDRV_PCM_FMTBIT_U24_LE | \
154 			SNDRV_PCM_FMTBIT_S32_LE | \
155 			SNDRV_PCM_FMTBIT_U32_LE | \
156 			SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE)
157 
158 /*
159  * Select these from Sound Card Manually
160  *	SND_SOC_POSSIBLE_DAIFMT_CBP_CFP
161  *	SND_SOC_POSSIBLE_DAIFMT_CBP_CFC
162  *	SND_SOC_POSSIBLE_DAIFMT_CBC_CFP
163  *	SND_SOC_POSSIBLE_DAIFMT_CBC_CFC
164  */
165 static u64 dummy_dai_formats =
166 	SND_SOC_POSSIBLE_DAIFMT_I2S	|
167 	SND_SOC_POSSIBLE_DAIFMT_RIGHT_J	|
168 	SND_SOC_POSSIBLE_DAIFMT_LEFT_J	|
169 	SND_SOC_POSSIBLE_DAIFMT_DSP_A	|
170 	SND_SOC_POSSIBLE_DAIFMT_DSP_B	|
171 	SND_SOC_POSSIBLE_DAIFMT_AC97	|
172 	SND_SOC_POSSIBLE_DAIFMT_PDM	|
173 	SND_SOC_POSSIBLE_DAIFMT_GATED	|
174 	SND_SOC_POSSIBLE_DAIFMT_CONT	|
175 	SND_SOC_POSSIBLE_DAIFMT_NB_NF	|
176 	SND_SOC_POSSIBLE_DAIFMT_NB_IF	|
177 	SND_SOC_POSSIBLE_DAIFMT_IB_NF	|
178 	SND_SOC_POSSIBLE_DAIFMT_IB_IF;
179 
180 static const struct snd_soc_dai_ops dummy_dai_ops = {
181 	.auto_selectable_formats	= &dummy_dai_formats,
182 	.num_auto_selectable_formats	= 1,
183 };
184 
185 /*
186  * The dummy CODEC is only meant to be used in situations where there is no
187  * actual hardware.
188  *
189  * If there is actual hardware even if it does not have a control bus
190  * the hardware will still have constraints like supported samplerates, etc.
191  * which should be modelled. And the data flow graph also should be modelled
192  * using DAPM.
193  */
194 static struct snd_soc_dai_driver dummy_dai = {
195 	.name = "snd-soc-dummy-dai",
196 	.playback = {
197 		.stream_name	= "Playback",
198 		.channels_min	= 1,
199 		.channels_max	= 384,
200 		.rates		= STUB_RATES,
201 		.formats	= STUB_FORMATS,
202 	},
203 	.capture = {
204 		.stream_name	= "Capture",
205 		.channels_min	= 1,
206 		.channels_max	= 384,
207 		.rates = STUB_RATES,
208 		.formats = STUB_FORMATS,
209 	 },
210 	.ops = &dummy_dai_ops,
211 };
212 
213 int snd_soc_dai_is_dummy(struct snd_soc_dai *dai)
214 {
215 	if (dai->driver == &dummy_dai)
216 		return 1;
217 	return 0;
218 }
219 
220 int snd_soc_component_is_dummy(struct snd_soc_component *component)
221 {
222 	return ((component->driver == &dummy_platform) ||
223 		(component->driver == &dummy_codec));
224 }
225 
226 static int snd_soc_dummy_probe(struct platform_device *pdev)
227 {
228 	int ret;
229 
230 	ret = devm_snd_soc_register_component(&pdev->dev,
231 					      &dummy_codec, &dummy_dai, 1);
232 	if (ret < 0)
233 		return ret;
234 
235 	ret = devm_snd_soc_register_component(&pdev->dev, &dummy_platform,
236 					      NULL, 0);
237 
238 	return ret;
239 }
240 
241 static struct platform_driver soc_dummy_driver = {
242 	.driver = {
243 		.name = "snd-soc-dummy",
244 	},
245 	.probe = snd_soc_dummy_probe,
246 };
247 
248 static struct platform_device *soc_dummy_dev;
249 
250 int __init snd_soc_util_init(void)
251 {
252 	int ret;
253 
254 	soc_dummy_dev =
255 		platform_device_register_simple("snd-soc-dummy", -1, NULL, 0);
256 	if (IS_ERR(soc_dummy_dev))
257 		return PTR_ERR(soc_dummy_dev);
258 
259 	ret = platform_driver_register(&soc_dummy_driver);
260 	if (ret != 0)
261 		platform_device_unregister(soc_dummy_dev);
262 
263 	return ret;
264 }
265 
266 void __exit snd_soc_util_exit(void)
267 {
268 	platform_driver_unregister(&soc_dummy_driver);
269 	platform_device_unregister(soc_dummy_dev);
270 }
271