drm/bridge: tfp410: Support format negotiation hooks

With new connector model, tfp410 will not create the connector and
SoC driver will rely on format negotiation to setup the encoder format.

Support format negotiations hooks in the drm_bridge_funcs.
Use helper functions for state management.

Input format is the one selected by the bridge from DT properties.

Signed-off-by: Nikhil Devshatwar <[email protected]>
[a-bhatia1: Removed output fmt condition check]
Signed-off-by: Aradhya Bhatia <[email protected]>
Reviewed-by: Neil Armstrong <[email protected]>
Reviewed-by: Tomi Valkeinen <[email protected]>
Signed-off-by: Javier Martinez Canillas <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: nikhildevshatwar

drivers/gpu/drm/bridge/ti-tfp410.c

@@ -206,12 +206,38 @@ static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
 	return MODE_OK;
 }
 
+static u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge,
+				      struct drm_bridge_state *bridge_state,
+				      struct drm_crtc_state *crtc_state,
+				      struct drm_connector_state *conn_state,
+				      u32 output_fmt,
+				      unsigned int *num_input_fmts)
+{
+	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
+	u32 *input_fmts;
+
+	*num_input_fmts = 0;
+
+	input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
+	if (!input_fmts)
+		return NULL;
+
+	*num_input_fmts = 1;
+	input_fmts[0] = dvi->bus_format;
+
+	return input_fmts;
+}
+
 static const struct drm_bridge_funcs tfp410_bridge_funcs = {
 	.attach		= tfp410_attach,
 	.detach		= tfp410_detach,
 	.enable		= tfp410_enable,
 	.disable	= tfp410_disable,
 	.mode_valid	= tfp410_mode_valid,
+	.atomic_reset = drm_atomic_helper_bridge_reset,
+	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+	.atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts,
 };
 
 static const struct drm_bridge_timings tfp410_default_timings = {