On 9/25/25 2:48 PM, Sebastian Reichel wrote:
Hello Sebastian,
On Thu, Sep 25, 2025 at 02:15:41AM +0200, Marek Vasut wrote:
On 9/24/25 11:46 PM, Sebastian Reichel wrote:
From: Sebastian Reichel <sebastian.reic...@collabora.com>
I planned to set the polarity of horizontal and vertical sync, but
accidentally described vertical sync twice with different polarity
instead.
Note, that there is no functional change, because the driver only
makes use of DRM_MODE_FLAG_P[HV]SYNC to divert from the default
active-low polarity.
Reported-by: Laurent Pinchart <laurent.pinchart+rene...@ideasonboard.com>
Closes:
https://lore.kernel.org/all/20250923132616.gh20...@pendragon.ideasonboard.com/
Fixes: a411558cc143 ("drm/panel: sitronix-st7789v: add Inanbo T28CP45TN89
support")
Signed-off-by: Sebastian Reichel <sebastian.reic...@collabora.com>
---
drivers/gpu/drm/panel/panel-sitronix-st7789v.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
b/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
index
04d91929eedda092b966b8cffdef5b267748f190..dedf0a390a88dd45a8179e2d22e872128c87cfda
100644
--- a/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
+++ b/drivers/gpu/drm/panel/panel-sitronix-st7789v.c
@@ -261,7 +261,7 @@ static const struct drm_display_mode t28cp45tn89_mode = {
.vtotal = 320 + 8 + 4 + 4,
.width_mm = 43,
.height_mm = 57,
- .flags = DRM_MODE_FLAG_PVSYNC | DRM_MODE_FLAG_NVSYNC,
+ .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC,
Is this panel somehow special with its NHSYNC / PVSYNC , compared to the
other supported panels, which all use PHSYNC / PVSYNC ? I would expect all
of these DSI TCON to use the same polarity, how come this one needs NHSYNC ?
I wrote this based on reverse engineering incl. quite a bit try-and-error and
don't have very good data about the panel. Using DRM_MODE_FLAG_PHSYNC like all
the other panels results in garbage data on the display.
Interesting.
Can you please add that information as a code comment in V2 and also add
to V2 my
Reviewed-by: Marek Vasut <marek.vasut+rene...@mailbox.org>
Thank you
