ASoC: meson: axg-fifo: fix fifo threshold setup

On TODDR sm1, the fifo threshold register field is slightly different
compared to the other SoCs. This leads to the fifo A being flushed to
memory every 8kB. If the period is smaller than that, several periods
are pushed to memory and notified at once. This is not ideal.

Fix the register field update. With this, the fifos are flushed every
128B. We could still do better, like adapt the threshold depending on
the period size, but at least it consistent across the different
SoC/fifos

Fixes: 5ac825c3d85e ("ASoC: meson: axg-toddr: add sm1 support")
Reported-by: Alden DSouza <aldend@google.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20191218172420.1199117-2-jbrunet@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 9 insertions, 12 deletions

diff --git a/sound/soc/meson/axg-toddr.c b/sound/soc/meson/axg-toddr.c
index f6023397c8fe..e711abcf8c12 100644
--- a/sound/soc/meson/axg-toddr.c
+++ b/sound/soc/meson/axg-toddr.c
@@ -89,7 +89,6 @@ static int axg_toddr_dai_startup(struct snd_pcm_substream *substream,
 				 struct snd_soc_dai *dai)
 {
 	struct axg_fifo *fifo = snd_soc_dai_get_drvdata(dai);
-	unsigned int fifo_threshold;
 	int ret;
 
 	/* Enable pclk to access registers and clock the fifo ip */
@@ -107,11 +106,6 @@ static int axg_toddr_dai_startup(struct snd_pcm_substream *substream,
 	/* Apply single buffer mode to the interface */
 	regmap_update_bits(fifo->map, FIFO_CTRL0, CTRL0_TODDR_PP_MODE, 0);
 
-	/* TODDR does not have a configurable fifo depth */
-	fifo_threshold = AXG_FIFO_MIN_CNT - 1;
-	regmap_update_bits(fifo->map, FIFO_CTRL1, CTRL1_THRESHOLD_MASK,
-			   CTRL1_THRESHOLD(fifo_threshold));
-
 	return 0;
 }
 
@@ -190,8 +184,9 @@ static const struct snd_soc_component_driver axg_toddr_component_drv = {
 };
 
 static const struct axg_fifo_match_data axg_toddr_match_data = {
-	.component_drv	= &axg_toddr_component_drv,
-	.dai_drv	= &axg_toddr_dai_drv
+	.field_threshold	= REG_FIELD(FIFO_CTRL1, 16, 23),
+	.component_drv		= &axg_toddr_component_drv,
+	.dai_drv		= &axg_toddr_dai_drv
 };
 
 static const struct snd_soc_dai_ops g12a_toddr_ops = {
@@ -228,8 +223,9 @@ static const struct snd_soc_component_driver g12a_toddr_component_drv = {
 };
 
 static const struct axg_fifo_match_data g12a_toddr_match_data = {
-	.component_drv	= &g12a_toddr_component_drv,
-	.dai_drv	= &g12a_toddr_dai_drv
+	.field_threshold	= REG_FIELD(FIFO_CTRL1, 16, 23),
+	.component_drv		= &g12a_toddr_component_drv,
+	.dai_drv		= &g12a_toddr_dai_drv
 };
 
 static const char * const sm1_toddr_sel_texts[] = {
@@ -297,8 +293,9 @@ static const struct snd_soc_component_driver sm1_toddr_component_drv = {
 };
 
 static const struct axg_fifo_match_data sm1_toddr_match_data = {
-	.component_drv	= &sm1_toddr_component_drv,
-	.dai_drv	= &g12a_toddr_dai_drv
+	.field_threshold	= REG_FIELD(FIFO_CTRL1, 12, 23),
+	.component_drv		= &sm1_toddr_component_drv,
+	.dai_drv		= &g12a_toddr_dai_drv
 };
 
 static const struct of_device_id axg_toddr_of_match[] = {