[PATCH RESEND 3/3] phy: rockchip: samsung-hdptx: Prevent Inter-Pair Skew from exceeding the limits

Cristian Ciocaltea cristian.ciocaltea at collabora.com
Tue Oct 28 01:00:56 PDT 2025


Fixup PHY deskew FIFO to prevent the phase of D2 lane going ahead of
other lanes.  It's worth noting this might only happen when dealing with
HDMI 2.0 rates.

Fixes: 553be2830c5f ("phy: rockchip: Add Samsung HDMI/eDP Combo PHY driver")
Co-developed-by: Algea Cao <algea.cao at rock-chips.com>
Signed-off-by: Algea Cao <algea.cao at rock-chips.com>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
---
 drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
index 8ba9b53c2309..29de2f7bdae8 100644
--- a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
+++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
@@ -668,13 +668,9 @@ static const struct reg_sequence rk_hdtpx_common_lane_init_seq[] = {
 
 static const struct reg_sequence rk_hdtpx_tmds_lane_init_seq[] = {
 	REG_SEQ0(LANE_REG(0312), 0x00),
-	REG_SEQ0(LANE_REG(031e), 0x00),
 	REG_SEQ0(LANE_REG(0412), 0x00),
-	REG_SEQ0(LANE_REG(041e), 0x00),
 	REG_SEQ0(LANE_REG(0512), 0x00),
-	REG_SEQ0(LANE_REG(051e), 0x00),
 	REG_SEQ0(LANE_REG(0612), 0x00),
-	REG_SEQ0(LANE_REG(061e), 0x08),
 	REG_SEQ0(LANE_REG(0303), 0x2f),
 	REG_SEQ0(LANE_REG(0403), 0x2f),
 	REG_SEQ0(LANE_REG(0503), 0x2f),
@@ -687,6 +683,11 @@ static const struct reg_sequence rk_hdtpx_tmds_lane_init_seq[] = {
 	REG_SEQ0(LANE_REG(0406), 0x1c),
 	REG_SEQ0(LANE_REG(0506), 0x1c),
 	REG_SEQ0(LANE_REG(0606), 0x1c),
+	/* Keep Inter-Pair Skew in the limits */
+	REG_SEQ0(LANE_REG(031e), 0x02),
+	REG_SEQ0(LANE_REG(041e), 0x02),
+	REG_SEQ0(LANE_REG(051e), 0x02),
+	REG_SEQ0(LANE_REG(061e), 0x0a),
 };
 
 static struct tx_drv_ctrl tx_drv_ctrl_rbr[4][4] = {

-- 
2.51.0




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