Unverified Commit 68a4f2ca authored by Samuel Holland's avatar Samuel Holland Committed by Mark Brown
Browse files

ASoC: sun8i-codec: Correct the BCLK divisor calculation 



Previously, the BCLK divisor calculation assumed zero padding and
exactly two slots. In order to support the TDM slot binding and
20/24-bit word sizes, those assumptions must be removed.

Due to hardware limitations, the BCLK/LRCK ratio is not as simple as
"slot_width * slots". However, the correct value is already calculated
elsewhere in this function, since it must also be programmed into the
hardware. Reuse that value to calculate the correct SYSCLK/BCLK divisor.

Acked-by: default avatarMaxime Ripard <mripard@kernel.org>
Signed-off-by: default avatarSamuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20201014061941.4306-7-samuel@sholland.org


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent e511aed7

sound/soc/sunxi/sun8i-codec.c

+9 −8
Original line number Diff line number Diff line
@@ -284,11 +284,11 @@ static const struct sun8i_codec_clk_div sun8i_codec_bclk_div[] = { 
};



static u8 sun8i_codec_get_bclk_div(struct sun8i_codec *scodec,

				   unsigned int rate,

				   unsigned int word_size)

				   unsigned int lrck_div_order,

				   unsigned int sample_rate)

{

	unsigned long clk_rate = clk_get_rate(scodec->clk_module);

	unsigned int div = clk_rate / rate / word_size / 2;

	unsigned int div = clk_rate / sample_rate >> lrck_div_order;

	unsigned int best_val = 0, best_diff = ~0;

	int i;
@@ -348,11 +348,6 @@ static int sun8i_codec_hw_params(struct snd_pcm_substream *substream, 
			   SUN8I_AIF1CLK_CTRL_AIF1_WORD_SIZ_MASK,

			   word_size << SUN8I_AIF1CLK_CTRL_AIF1_WORD_SIZ);



	bclk_div = sun8i_codec_get_bclk_div(scodec, params_rate(params), 16);

	regmap_update_bits(scodec->regmap, SUN8I_AIF1CLK_CTRL,

			   SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV_MASK,

			   bclk_div << SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV);



	/* LRCK divider (BCLK/LRCK ratio) */

	lrck_div_order = sun8i_codec_get_lrck_div_order(slots, slot_width);

	if (lrck_div_order < 0)
@@ -362,6 +357,12 @@ static int sun8i_codec_hw_params(struct snd_pcm_substream *substream, 
			   SUN8I_AIF1CLK_CTRL_AIF1_LRCK_DIV_MASK,

			   (lrck_div_order - 4) << SUN8I_AIF1CLK_CTRL_AIF1_LRCK_DIV);



	/* BCLK divider (SYSCLK/BCLK ratio) */

	bclk_div = sun8i_codec_get_bclk_div(scodec, lrck_div_order, params_rate(params));

	regmap_update_bits(scodec->regmap, SUN8I_AIF1CLK_CTRL,

			   SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV_MASK,

			   bclk_div << SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV);



	sample_rate = sun8i_codec_get_hw_rate(params);

	if (sample_rate < 0)

		return sample_rate;

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