[PATCH] drm/msm/mdp5: Always generate active-high sync signals for DSI

From: Hai Li
Date: Fri May 22 2015 - 10:17:13 EST


DSI video mode engine can only take active-high sync signals. This
change prevents MDP5 sending active-low sync signals to DSI in any
case.

Signed-off-by: Hai Li <hali@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
index 53bb1f7..2e98ce0 100644
--- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
+++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
@@ -144,10 +144,14 @@ static void mdp5_encoder_mode_set(struct drm_encoder *encoder,
mode->type, mode->flags);

ctrl_pol = 0;
- if (mode->flags & DRM_MODE_FLAG_NHSYNC)
- ctrl_pol |= MDP5_INTF_POLARITY_CTL_HSYNC_LOW;
- if (mode->flags & DRM_MODE_FLAG_NVSYNC)
- ctrl_pol |= MDP5_INTF_POLARITY_CTL_VSYNC_LOW;
+
+ /* DSI controller cannot handle active-low sync signals. */
+ if (mdp5_encoder->intf.type != INTF_DSI) {
+ if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+ ctrl_pol |= MDP5_INTF_POLARITY_CTL_HSYNC_LOW;
+ if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+ ctrl_pol |= MDP5_INTF_POLARITY_CTL_VSYNC_LOW;
+ }
/* probably need to get DATA_EN polarity from panel.. */

dtv_hsync_skew = 0; /* get this from panel? */
--
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