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ASoC: EDB93xx: Manage I2S rates according to datasheet for CS4271 CODEC.
Manage I2S rates according to datasheet for CS4271 CODEC in EDB93xx
machine driver.
Signed-off-by: Alexander Sverdlin <subaparts@yandex.ru>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
authored by
Alexander Sverdlin
and committed by
Mark Brown
6d33cd77
5c3a12e9
+8
-8
sound/soc/ep93xx/edb93xx.c
+8
-8
sound/soc/ep93xx/edb93xx.c
···
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struct snd_soc_dai *codec_dai = rtd->codec_dai;
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struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
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int err;
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unsigned int mclk_rate;
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unsigned int rate = params_rate(params);
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/*
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* We set LRCLK equal to `rate' and SCLK = LRCLK * 64,
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* because our sample size is 32 bit * 2 channels.
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* I2S standard permits us to transmit more bits than
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* the codec uses.
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* MCLK = SCLK * 4 is the best recommended value,
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* but we have to fall back to ratio 2 for higher
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* sample rates.
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* According to CS4271 datasheet we use MCLK/LRCK=256 for
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* rates below 50kHz and 128 for higher sample rates
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*/
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unsigned int mclk_rate = rate * 64 * ((rate <= 48000) ? 4 : 2);
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if (rate < 50000)
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mclk_rate = rate * 64 * 4;
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else
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mclk_rate = rate * 64 * 2;
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err = snd_soc_dai_set_fmt(codec_dai, SND_SOC_DAIFMT_I2S |
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SND_SOC_DAIFMT_NB_IF |