On Sun, 3 Oct 2021 at 01:35, Dmitry Osipenko <digetx@xxxxxxxxx> wrote: > > Calculate video start delay based on the display timing instead > of hardcoding it to a default value. This fixes "trembling" display > output on Asus Transformer TF700T which uses Panasonic VVX10F004B00 > display panel. > > Tested-by: Andreas Westman Dorcsak <hedmoo@xxxxxxxxx> # Asus TF700T > Tested-by: Maxim Schwalm <maxim.schwalm@xxxxxxxxx> #TF700T > Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> > --- > drivers/gpu/drm/bridge/tc358768.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c > index 10ebd0621ad3..5b3f8723bd3d 100644 > --- a/drivers/gpu/drm/bridge/tc358768.c > +++ b/drivers/gpu/drm/bridge/tc358768.c > @@ -634,7 +634,8 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) > u32 val, val2, lptxcnt, hact, data_type; > const struct drm_display_mode *mode; > u32 dsibclk_nsk, dsiclk_nsk, ui_nsk, phy_delay_nsk; > - u32 dsiclk, dsibclk; > + u32 dsiclk, dsibclk, video_start; > + const u32 internal_delay = 40; > int ret, i; > > tc358768_hw_enable(priv); > @@ -663,23 +664,27 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) > case MIPI_DSI_FMT_RGB888: > val |= (0x3 << 4); > hact = mode->hdisplay * 3; > + video_start = (mode->htotal - mode->hsync_start) * 3; > data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24; > break; > case MIPI_DSI_FMT_RGB666: > val |= (0x4 << 4); > hact = mode->hdisplay * 3; > + video_start = (mode->htotal - mode->hsync_start) * 3; > data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18; > break; > > case MIPI_DSI_FMT_RGB666_PACKED: > val |= (0x4 << 4) | BIT(3); > hact = mode->hdisplay * 18 / 8; > + video_start = (mode->htotal - mode->hsync_start) * 18 / 8; > data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18; > break; > > case MIPI_DSI_FMT_RGB565: > val |= (0x5 << 4); > hact = mode->hdisplay * 2; > + video_start = (mode->htotal - mode->hsync_start) * 2; > data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16; > break; > default: > @@ -690,7 +695,8 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) > } > > /* VSDly[9:0] */ > - tc358768_write(priv, TC358768_VSDLY, 1); > + video_start = max(video_start, internal_delay + 1) - internal_delay; > + tc358768_write(priv, TC358768_VSDLY, video_start); > > tc358768_write(priv, TC358768_DATAFMT, val); > tc358768_write(priv, TC358768_DSITX_DT, data_type); > -- > 2.32.0 > Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>
