[PATCH 4.4 265/268] ASoC: samsung: i2s: Ensure the RCLK rate is properly determined

From: Greg Kroah-Hartman
Date: Mon May 28 2018 - 06:26:10 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>

[ Upstream commit 647d04f8e07afc7c3b7a42b3ee01a8b28db29631 ]

If the RCLK mux clock configuration is specified in DT and no set_sysclk()
callback is used in the sound card driver the sclk_srcrate field will remain
set to 0, leading to an incorrect PSR divider setting.
To fix this the frequency value is retrieved from the CLK_I2S_RCLK_SRC clock,
so the actual RCLK mux selection is taken into account.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx>
Acked-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/soc/samsung/i2s.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

--- a/sound/soc/samsung/i2s.c
+++ b/sound/soc/samsung/i2s.c
@@ -640,8 +640,12 @@ static int i2s_set_fmt(struct snd_soc_da
tmp |= mod_slave;
break;
case SND_SOC_DAIFMT_CBS_CFS:
- /* Set default source clock in Master mode */
- if (i2s->rclk_srcrate == 0)
+ /*
+ * Set default source clock in Master mode, only when the
+ * CLK_I2S_RCLK_SRC clock is not exposed so we ensure any
+ * clock configuration assigned in DT is not overwritten.
+ */
+ if (i2s->rclk_srcrate == 0 && i2s->clk_data.clks == NULL)
i2s_set_sysclk(dai, SAMSUNG_I2S_RCLKSRC_0,
0, SND_SOC_CLOCK_IN);
break;
@@ -856,6 +860,11 @@ static int config_setup(struct i2s_dai *
return 0;

if (!(i2s->quirks & QUIRK_NO_MUXPSR)) {
+ struct clk *rclksrc = i2s->clk_table[CLK_I2S_RCLK_SRC];
+
+ if (i2s->rclk_srcrate == 0 && rclksrc && !IS_ERR(rclksrc))
+ i2s->rclk_srcrate = clk_get_rate(rclksrc);
+
psr = i2s->rclk_srcrate / i2s->frmclk / rfs;
writel(((psr - 1) << 8) | PSR_PSREN, i2s->addr + I2SPSR);
dev_dbg(&i2s->pdev->dev,