drm/bridge: lt9611: fix sync polarity for DVI output

Attaching DVI sink to the lt9611 requires different setup. Fix the
register write to make the DVI displays sync onto the correct sync
pulse.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230118081658.2198520-10-dmitry.baryshkov@linaro.org

diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index ab411e4..1ea6436 100644 (file)
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -353,13 +353,16 @@ end:
        return temp;
 }
 
-static void lt9611_hdmi_tx_digital(struct lt9611 *lt9611)
+static void lt9611_hdmi_tx_digital(struct lt9611 *lt9611, bool is_hdmi)
 {
        regmap_write(lt9611->regmap, 0x8443, 0x46 - lt9611->vic);
        regmap_write(lt9611->regmap, 0x8447, lt9611->vic);
        regmap_write(lt9611->regmap, 0x843d, 0x0a); /* UD1 infoframe */
 
-       regmap_write(lt9611->regmap, 0x82d6, 0x8c);
+       if (is_hdmi)
+               regmap_write(lt9611->regmap, 0x82d6, 0x8c);
+       else
+               regmap_write(lt9611->regmap, 0x82d6, 0x0c);
        regmap_write(lt9611->regmap, 0x82d7, 0x04);
 }
 
@@ -720,7 +723,7 @@ lt9611_bridge_atomic_enable(struct drm_bridge *bridge,
        }
 
        lt9611_mipi_input_analog(lt9611);
-       lt9611_hdmi_tx_digital(lt9611);
+       lt9611_hdmi_tx_digital(lt9611, connector->display_info.is_hdmi);
        lt9611_hdmi_tx_phy(lt9611);
 
        msleep(500);