From: Alexander Sverdlin Date: Mon, 7 Mar 2011 17:29:53 +0000 (+0300) Subject: ASoC: EDB93xx: Manage I2S rates according to datasheet for CS4271 CODEC. X-Git-Tag: firefly_0821_release~3680^2~2691^2~1145^2~14 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6d33cd771b779abd8faeaf63821c200ba36a63b1;p=firefly-linux-kernel-4.4.55.git 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 Acked-by: Liam Girdwood Signed-off-by: Mark Brown --- diff --git a/sound/soc/ep93xx/edb93xx.c b/sound/soc/ep93xx/edb93xx.c index b270085227f3..d3aa15119d26 100644 --- a/sound/soc/ep93xx/edb93xx.c +++ b/sound/soc/ep93xx/edb93xx.c @@ -41,17 +41,17 @@ static int edb93xx_hw_params(struct snd_pcm_substream *substream, struct snd_soc_dai *codec_dai = rtd->codec_dai; struct snd_soc_dai *cpu_dai = rtd->cpu_dai; int err; + unsigned int mclk_rate; unsigned int rate = params_rate(params); + /* - * We set LRCLK equal to `rate' and SCLK = LRCLK * 64, - * because our sample size is 32 bit * 2 channels. - * I2S standard permits us to transmit more bits than - * the codec uses. - * MCLK = SCLK * 4 is the best recommended value, - * but we have to fall back to ratio 2 for higher - * sample rates. + * According to CS4271 datasheet we use MCLK/LRCK=256 for + * rates below 50kHz and 128 for higher sample rates */ - unsigned int mclk_rate = rate * 64 * ((rate <= 48000) ? 4 : 2); + if (rate < 50000) + mclk_rate = rate * 64 * 4; + else + mclk_rate = rate * 64 * 2; err = snd_soc_dai_set_fmt(codec_dai, SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_IF |