[PATCH 1/1] drm/panel: st7703: Fix vertical refresh rate of XBD599

From: Frank Oltmanns
Date: Sun Feb 19 2023 - 06:46:34 EST


Fix the XBD599 panel's slight visual stutter by correcting the pixel
clock speed so that the panel's 60Hz vertical refresh rate is met.

Set the clock speed using the underlying formula instead of a magic
number. To have a consistent procedure for both panels, set the JH057N
panel's clock also as a formula.
---
drivers/gpu/drm/panel/panel-sitronix-st7703.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7703.c b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
index 6747ca237ced..cd7d631f7573 100644
--- a/drivers/gpu/drm/panel/panel-sitronix-st7703.c
+++ b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
@@ -139,7 +139,7 @@ static const struct drm_display_mode jh057n00900_mode = {
.vsync_start = 1440 + 20,
.vsync_end = 1440 + 20 + 4,
.vtotal = 1440 + 20 + 4 + 12,
- .clock = 75276,
+ .clock = (720 + 90 + 20 + 20) * (1440 + 20 + 4 + 12) * 60 / 1000,
.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
.width_mm = 65,
.height_mm = 130,
@@ -324,7 +324,7 @@ static const struct drm_display_mode xbd599_mode = {
.vsync_start = 1440 + 18,
.vsync_end = 1440 + 18 + 10,
.vtotal = 1440 + 18 + 10 + 17,
- .clock = 69000,
+ .clock = (720 + 40 + 40 + 40) * (1440 + 18 + 10 + 17) * 60 / 1000,
.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
.width_mm = 68,
.height_mm = 136,
--
2.39.1