[alsa-devel] [PATCH v5 03/15] ASoC: sun4i-i2s: Correct divider calculations

[codekipper at gmail.com]

From: Marcus Cooper <codekipper at gmail.com>

The clock division circuitry is different on the H3 and later SoCs.
The division of bclk is now based on pll2.

Signed-off-by: Marcus Cooper <codekipper at gmail.com>
---
 sound/soc/sunxi/sun4i-i2s.c | 73 +++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 24 deletions(-)

diff --git a/sound/soc/sunxi/sun4i-i2s.c b/sound/soc/sunxi/sun4i-i2s.c
index 7c37b6291df0..34f31439ae7b 100644
--- a/sound/soc/sunxi/sun4i-i2s.c
+++ b/sound/soc/sunxi/sun4i-i2s.c
@@ -127,8 +127,6 @@ struct sun4i_i2s;
  * @has_chsel_offset: SoC uses offset for selecting dai operational mode.
  * @reg_offset_txdata: offset of the tx fifo.
  * @sun4i_i2s_regmap: regmap config to use.
- * @mclk_offset: Value by which mclkdiv needs to be adjusted.
- * @bclk_offset: Value by which bclkdiv needs to be adjusted.
  * @field_clkdiv_mclk_en: regmap field to enable mclk output.
  * @field_fmt_wss: regmap field to set word select size.
  * @field_fmt_sr: regmap field to set sample resolution.
@@ -150,8 +148,6 @@ struct sun4i_i2s_quirks {
 	bool				has_chsel_offset;
 	unsigned int			reg_offset_txdata;	/* TX FIFO */
 	const struct regmap_config	*sun4i_i2s_regmap;
-	unsigned int			mclk_offset;
-	unsigned int			bclk_offset;
 
 	/* Register fields for i2s */
 	struct reg_field		field_clkdiv_mclk_en;
@@ -212,7 +208,25 @@ static const struct sun4i_i2s_clk_div sun4i_i2s_bclk_div[] = {
 	{ .div = 8, .val = 3 },
 	{ .div = 12, .val = 4 },
 	{ .div = 16, .val = 5 },
-	/* TODO - extend divide ratio supported by newer SoCs */
+};
+
+static const struct sun4i_i2s_clk_div sun8i_i2s_clk_div[] = {
+	{ .div = 0, .val = 0 },
+	{ .div = 1, .val = 1 },
+	{ .div = 2, .val = 2 },
+	{ .div = 4, .val = 3 },
+	{ .div = 6, .val = 4 },
+	{ .div = 8, .val = 5 },
+	{ .div = 12, .val = 6 },
+	{ .div = 16, .val = 7 },
+	{ .div = 24, .val = 8 },
+	{ .div = 32, .val = 9 },
+	{ .div = 48, .val = 10 },
+	{ .div = 64, .val = 11 },
+	{ .div = 96, .val = 12 },
+	{ .div = 128, .val = 13 },
+	{ .div = 176, .val = 14 },
+	{ .div = 192, .val = 15 },
 };
 
 static const struct sun4i_i2s_clk_div sun4i_i2s_mclk_div[] = {
@@ -224,21 +238,21 @@ static const struct sun4i_i2s_clk_div sun4i_i2s_mclk_div[] = {
 	{ .div = 12, .val = 5 },
 	{ .div = 16, .val = 6 },
 	{ .div = 24, .val = 7 },
-	/* TODO - extend divide ratio supported by newer SoCs */
 };
 
 static int sun4i_i2s_get_bclk_div(struct sun4i_i2s *i2s,
 				  unsigned int oversample_rate,
-				  unsigned int word_size)
+				  unsigned int word_size,
+				  const struct sun4i_i2s_clk_div *bdiv,
+				  unsigned int size)
 {
 	int div = oversample_rate / word_size / 2;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(sun4i_i2s_bclk_div); i++) {
-		const struct sun4i_i2s_clk_div *bdiv = &sun4i_i2s_bclk_div[i];
-
+	for (i = 0; i < size; i++) {
 		if (bdiv->div == div)
 			return bdiv->val;
+		bdiv++;
 	}
 
 	return -EINVAL;
@@ -247,16 +261,17 @@ 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 int sampling_rate,
+				  const struct sun4i_i2s_clk_div *mdiv,
+				  unsigned int size)
 {
 	int div = module_rate / sampling_rate / oversample_rate;
 	int i;
 
-	for (i = 0; i < ARRAY_SIZE(sun4i_i2s_mclk_div); i++) {
-		const struct sun4i_i2s_clk_div *mdiv = &sun4i_i2s_mclk_div[i];
-
+	for (i = 0; i < size; i++) {
 		if (mdiv->div == div)
 			return mdiv->val;
+		mdiv++;
 	}
 
 	return -EINVAL;
@@ -321,24 +336,36 @@ static int sun4i_i2s_set_clk_rate(struct snd_soc_dai *dai,
 		return -EINVAL;
 	}
 
-	bclk_div = sun4i_i2s_get_bclk_div(i2s, oversample_rate,
-					  word_size);
+	if (i2s->variant->has_fmt_set_lrck_period)
+		bclk_div = sun4i_i2s_get_bclk_div(i2s, clk_rate / rate,
+						  word_size,
+						  sun8i_i2s_clk_div,
+						  ARRAY_SIZE(sun8i_i2s_clk_div));
+	else
+		bclk_div = sun4i_i2s_get_bclk_div(i2s, oversample_rate,
+						  word_size,
+						  sun4i_i2s_bclk_div,
+						  ARRAY_SIZE(sun4i_i2s_bclk_div));
 	if (bclk_div < 0) {
 		dev_err(dai->dev, "Unsupported BCLK divider: %d\n", bclk_div);
 		return -EINVAL;
 	}
 
-	mclk_div = sun4i_i2s_get_mclk_div(i2s, oversample_rate,
-					  clk_rate, rate);
+	if (i2s->variant->has_fmt_set_lrck_period)
+		mclk_div = sun4i_i2s_get_mclk_div(i2s, oversample_rate,
+						  clk_rate, rate,
+						  sun8i_i2s_clk_div,
+						  ARRAY_SIZE(sun8i_i2s_clk_div));
+	else
+		mclk_div = sun4i_i2s_get_mclk_div(i2s, oversample_rate,
+						  clk_rate, rate,
+						  sun4i_i2s_mclk_div,
+						  ARRAY_SIZE(sun4i_i2s_mclk_div));
 	if (mclk_div < 0) {
 		dev_err(dai->dev, "Unsupported MCLK divider: %d\n", mclk_div);
 		return -EINVAL;
 	}
 
-	/* Adjust the clock division values if needed */
-	bclk_div += i2s->variant->bclk_offset;
-	mclk_div += i2s->variant->mclk_offset;
-
 	regmap_write(i2s->regmap, SUN4I_I2S_CLK_DIV_REG,
 		     SUN4I_I2S_CLK_DIV_BCLK(bclk_div) |
 		     SUN4I_I2S_CLK_DIV_MCLK(mclk_div));
@@ -994,8 +1021,6 @@ static const struct sun4i_i2s_quirks sun8i_h3_i2s_quirks = {
 	.has_reset		= true,
 	.reg_offset_txdata	= SUN8I_I2S_FIFO_TX_REG,
 	.sun4i_i2s_regmap	= &sun8i_i2s_regmap_config,
-	.mclk_offset		= 1,
-	.bclk_offset		= 2,
 	.has_fmt_set_lrck_period = true,
 	.has_chcfg		= true,
 	.has_chsel_tx_chen	= true,
-- 
2.22.0