xref: /openbmc/linux/sound/soc/soc-utils.c (revision 1edd0337)
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, 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  */
82 int 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(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(params_format(params));
93 		if (tdm_width < 0)
94 			return tdm_width;
95 	}
96 
97 	return snd_soc_calc_bclk(params_rate(params), tdm_width, 1, tdm_slots);
98 }
99 EXPORT_SYMBOL_GPL(snd_soc_tdm_params_to_bclk);
100 
101 static 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 
113 static const struct snd_soc_component_driver dummy_platform;
114 
115 static int dummy_dma_open(struct snd_soc_component *component,
116 			  struct snd_pcm_substream *substream)
117 {
118 	struct snd_soc_pcm_runtime *rtd = asoc_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, &dummy_dma_hardware);
133 
134 	return 0;
135 }
136 
137 static const struct snd_soc_component_driver dummy_platform = {
138 	.open		= dummy_dma_open,
139 };
140 
141 static 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  */
166 static 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 
181 static 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  */
195 static 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 
214 int snd_soc_dai_is_dummy(struct snd_soc_dai *dai)
215 {
216 	if (dai->driver == &dummy_dai)
217 		return 1;
218 	return 0;
219 }
220 
221 int snd_soc_component_is_dummy(struct snd_soc_component *component)
222 {
223 	return ((component->driver == &dummy_platform) ||
224 		(component->driver == &dummy_codec));
225 }
226 
227 static int snd_soc_dummy_probe(struct platform_device *pdev)
228 {
229 	int ret;
230 
231 	ret = devm_snd_soc_register_component(&pdev->dev,
232 					      &dummy_codec, &dummy_dai, 1);
233 	if (ret < 0)
234 		return ret;
235 
236 	ret = devm_snd_soc_register_component(&pdev->dev, &dummy_platform,
237 					      NULL, 0);
238 
239 	return ret;
240 }
241 
242 static struct platform_driver soc_dummy_driver = {
243 	.driver = {
244 		.name = "snd-soc-dummy",
245 	},
246 	.probe = snd_soc_dummy_probe,
247 };
248 
249 static struct platform_device *soc_dummy_dev;
250 
251 int __init snd_soc_util_init(void)
252 {
253 	int ret;
254 
255 	soc_dummy_dev =
256 		platform_device_register_simple("snd-soc-dummy", -1, NULL, 0);
257 	if (IS_ERR(soc_dummy_dev))
258 		return PTR_ERR(soc_dummy_dev);
259 
260 	ret = platform_driver_register(&soc_dummy_driver);
261 	if (ret != 0)
262 		platform_device_unregister(soc_dummy_dev);
263 
264 	return ret;
265 }
266 
267 void snd_soc_util_exit(void)
268 {
269 	platform_driver_unregister(&soc_dummy_driver);
270 	platform_device_unregister(soc_dummy_dev);
271 }
272