drm/bridge: sii902x: Set input_bus_flags in atomic_check

input_bus_flags are specified in drm_bridge_timings (legacy) as well
as drm_bridge_state->input_bus_cfg.flags

The flags from the timings will be deprecated. Bridges are supposed
to validate and set the bridge state flags from atomic_check.

Implement atomic_check hook for the same.

Signed-off-by: Aradhya Bhatia <[e-mail]>
Reviewed-by: Neil Armstrong <[e-mail]>
Reviewed-by: Tomi Valkeinen <[e-mail]>
Signed-off-by: Javier Martinez Canillas <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/bridge/sii902x.c

···
 	return input_fmts;
 }
 
+static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
+				       struct drm_bridge_state *bridge_state,
+				       struct drm_crtc_state *crtc_state,
+				       struct drm_connector_state *conn_state)
+{
+	/*
+	 * There might be flags negotiation supported in future but
+	 * set the bus flags in atomic_check statically for now.
+	 */
+	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;
+
+	return 0;
+}
+
 static const struct drm_bridge_funcs sii902x_bridge_funcs = {
 	.attach = sii902x_bridge_attach,
 	.mode_set = sii902x_bridge_mode_set,
···
 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 	.atomic_get_input_bus_fmts = sii902x_bridge_atomic_get_input_bus_fmts,
+	.atomic_check = sii902x_bridge_atomic_check,
 };
 
 static int sii902x_mute(struct sii902x *sii902x, bool mute)