drm/tegra: dsi: Calculate packet parameters for video mode

Calculate packet parameters for video mode same way it is done for
command mode, by halving timings plugged into equations.

Signed-off-by: Svyatoslav Ryhel <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>
Link: https://patch.msgid.link/[e-mail]

drivers/gpu/drm/tegra/dsi.c

···
 		/* horizontal back porch */
 		hbp = (mode->htotal - mode->hsync_end) * mul / div;
 
-		if ((dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) == 0)
-			hbp += hsw;
-
 		/* horizontal front porch */
 		hfp = (mode->hsync_start - mode->hdisplay) * mul / div;
+
+		if (dsi->master || dsi->slave) {
+			hact /= 2;
+			hsw /= 2;
+			hbp /= 2;
+			hfp /= 2;
+		}
+
+		if ((dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) == 0)
+			hbp += hsw;
 
 		/* subtract packet overhead */
 		hsw -= 10;