ASoC: sun4i-i2s: Rework MCLK divider calculation (8bcf62b7) · Commits · 戴 / test

The MCLK divider calculation is currently computing the ideal divider using the oversample rate, the sample rate and the parent rate. However, since we have access to the frequency is supposed to be running at already, and as it turns out we're using it to compute the oversample rate, we can just use the ratio between the parent rate and the MCLK rate to simplify a bit the formula. Signed-off-by:

Maxime Ripard <maxime.ripard@bootlin.com> Link: https://lore.kernel.org/r/dcc5deb2eb650758d268bddd20f60ba58856d024.1566242458.git-series.maxime.ripard@bootlin.com Signed-off-by:

Mark Brown <broonie@kernel.org>

sound/soc/sunxi/sun4i-i2s.c

+4 −6

Original line number	Diff line number	Diff line
		@@ -240,11 +240,10 @@ static int sun4i_i2s_get_bclk_div(struct sun4i_i2s *i2s,
		}

		static int sun4i_i2s_get_mclk_div(struct sun4i_i2s *i2s,
		unsigned int oversample_rate,
		unsigned int module_rate,
		unsigned int sampling_rate)
		unsigned long parent_rate,
		unsigned long mclk_rate)
		{
		int div = module_rate / sampling_rate / oversample_rate;
		int div = parent_rate / mclk_rate;
		int i;

		for (i = 0; i < ARRAY_SIZE(sun4i_i2s_mclk_div); i++) {
		@@ -323,8 +322,7 @@ static int sun4i_i2s_set_clk_rate(struct snd_soc_dai *dai,
		return -EINVAL;
		}

		mclk_div = sun4i_i2s_get_mclk_div(i2s, oversample_rate,
		clk_rate, rate);
		mclk_div = sun4i_i2s_get_mclk_div(i2s, clk_rate, i2s->mclk_freq);
		if (mclk_div < 0) {
		dev_err(dai->dev, "Unsupported MCLK divider: %d\n", mclk_div);
		return -EINVAL;

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