From b468a785bd3e0a0591c84cbde5787f58be38c3e4 Mon Sep 17 00:00:00 2001
From: randerwang <rander.wang@linux.intel.com>
Date: Tue, 17 Mar 2020 11:33:29 -0500
Subject: [PATCH] soundwire: cadence: clear FIFO to avoid pop noise issue on playback start
Git-commit: b468a785bd3e0a0591c84cbde5787f58be38c3e4
Patch-mainline: v5.7-rc1
References: jsc#SLE-16518

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@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200317163329.25501-18-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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);
 }
-- 
2.16.4