drm: bridge: ldb: Drop DE flip from Freescale i.MX8MP LDB bridge

The DE inversion is implemented in LCDIFv3 driver and is no longer
needed in the LDB bridge which does not invert the DE signal. Drop
the inversion.

Fixes: 463db5c2 ("drm: bridge: ldb: Implement simple Freescale i.MX8MP LDB bridge")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Robby Cai <robby.cai@nxp.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
To: dri-devel@lists.freedesktop.org
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220630174031.92354-1-marex@denx.de

drivers/gpu/drm/bridge/fsl-ldb.c

@@ -75,22 +75,6 @@ static int fsl_ldb_attach(struct drm_bridge *bridge,
 				 bridge, flags);
 }
 
-static int fsl_ldb_atomic_check(struct drm_bridge *bridge,
-				struct drm_bridge_state *bridge_state,
-				struct drm_crtc_state *crtc_state,
-				struct drm_connector_state *conn_state)
-{
-	/* Invert DE signal polarity. */
-	bridge_state->input_bus_cfg.flags &= ~(DRM_BUS_FLAG_DE_LOW |
-					       DRM_BUS_FLAG_DE_HIGH);
-	if (bridge_state->output_bus_cfg.flags & DRM_BUS_FLAG_DE_LOW)
-		bridge_state->input_bus_cfg.flags |= DRM_BUS_FLAG_DE_HIGH;
-	else if (bridge_state->output_bus_cfg.flags & DRM_BUS_FLAG_DE_HIGH)
-		bridge_state->input_bus_cfg.flags |= DRM_BUS_FLAG_DE_LOW;
-
-	return 0;
-}
-
 static void fsl_ldb_atomic_enable(struct drm_bridge *bridge,
 				  struct drm_bridge_state *old_bridge_state)
 {
@@ -242,7 +226,6 @@ fsl_ldb_mode_valid(struct drm_bridge *bridge,
 
 static const struct drm_bridge_funcs funcs = {
 	.attach = fsl_ldb_attach,
-	.atomic_check = fsl_ldb_atomic_check,
 	.atomic_enable = fsl_ldb_atomic_enable,
 	.atomic_disable = fsl_ldb_atomic_disable,
 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,