[PATCH] soundwire: cadence: do not extend reset delay

From: Bard Liao
Date: Tue Aug 17 2021 - 23:01:57 EST


From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>

The duration of the hw_reset is defined as 4096 cycles. The Cadence IP
allows for an additional delay which doesn't seem necessary in
practice: the actual reset sequence duration is defined by the sync_go
mechanism, not by the IP itself.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
drivers/soundwire/cadence_master.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 0b7f037e6cd0..4fcc3ba93004 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -1032,10 +1032,7 @@ EXPORT_SYMBOL(sdw_cdns_check_self_clearing_bits);
*/
int sdw_cdns_exit_reset(struct sdw_cdns *cdns)
{
- /* program maximum length reset to be safe */
- cdns_updatel(cdns, CDNS_MCP_CONTROL,
- CDNS_MCP_CONTROL_RST_DELAY,
- CDNS_MCP_CONTROL_RST_DELAY);
+ /* keep reset delay unchanged to 4096 cycles */

/* use hardware generated reset */
cdns_updatel(cdns, CDNS_MCP_CONTROL,
--
2.17.1