[PATCH v2 17/17] soundwire: cadence: clear FIFO to avoid pop noise issue on playback start

[Pierre-Louis Bossart]

From: randerwang <rander.wang at linux.intel.com>

Driver should clear FIFO in PDI, or the previously stored sample data
in FIFO will generate pop noise when stream is started. The soft reset
bit will clear all the FIFO to zero and is self-cleared after that.

Signed-off-by: randerwang <rander.wang at linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
---
 drivers/soundwire/cadence_master.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index eedc4cefdab0..ecd357d1c63d 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -1503,6 +1503,7 @@ void sdw_cdns_config_stream(struct sdw_cdns *cdns,
 	cdns_updatel(cdns, offset, CDNS_PORTCTRL_DIRN, val);
 
 	val = pdi->num;
+	val |= CDNS_PDI_CONFIG_SOFT_RESET;
 	val |= ((1 << ch) - 1) << SDW_REG_SHIFT(CDNS_PDI_CONFIG_CHANNEL);
 	cdns_writel(cdns, CDNS_PDI_CONFIG(pdi->num), val);
 }
-- 
2.20.1