It turns out that the hblk calculation actually follows a similar pattern than the other packets. Rework a bit the calculation and add a comment. Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> --- drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c index 8e6392831e9d..e0288e7dc64e 100644 --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c @@ -488,9 +488,13 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi, (mode->hsync_start - mode->hdisplay) * Bpp - HFP_PACKET_OVERHEAD); /* - * hblk seems to be the line + porches length. + * The blanking is set using a sync event (4 bytes) and a + * blanking packet (4 bytes + payload + 2 bytes). Its minimal + * size is therefore 10 bytes. */ - hblk = mode->htotal * Bpp - hsa; +#define HBLK_PACKET_OVERHEAD 10 + hblk = max((unsigned int)HBLK_PACKET_OVERHEAD, + (mode->htotal - (mode->hsync_end - mode->hsync_start)) * Bpp - HBLK_PACKET_OVERHEAD); /* * And I'm not entirely sure what vblk is about. The driver in -- git-series 0.9.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel