drm/bridge: cdns-dsi: Add input format negotiation

Add support for the input format negotiation hook, that uses the helper
drm_mipi_dsi_get_input_bus_fmt() for dsi hosts, to figure out the
required input format.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@linux.dev>
Link: https://lore.kernel.org/r/20250329113925.68204-9-aradhya.bhatia@linux.dev
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
index 89a3f3efc522a6d23c9228a85a5b3176551ebea7..c333b5c025d9680c13839aa8655b2f7dc952996e 100644 (file)
--- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
@@ -936,6 +936,33 @@ static void cdns_dsi_bridge_atomic_pre_enable(struct drm_bridge *bridge,
        cdns_dsi_hs_init(dsi);
 }
 
+static u32 *cdns_dsi_bridge_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 cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge);
+       struct cdns_dsi *dsi = input_to_dsi(input);
+       struct cdns_dsi_output *output = &dsi->output;
+       u32 *input_fmts;
+
+       *num_input_fmts = 0;
+
+       input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
+       if (!input_fmts)
+               return NULL;
+
+       input_fmts[0] = drm_mipi_dsi_get_input_bus_fmt(output->dev->format);
+       if (!input_fmts[0])
+               return NULL;
+
+       *num_input_fmts = 1;
+
+       return input_fmts;
+}
+
 static const struct drm_bridge_funcs cdns_dsi_bridge_funcs = {
        .attach = cdns_dsi_bridge_attach,
        .mode_valid = cdns_dsi_bridge_mode_valid,
@@ -946,6 +973,7 @@ static const struct drm_bridge_funcs cdns_dsi_bridge_funcs = {
        .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 = cdns_dsi_bridge_get_input_bus_fmts,
 };
 
 static int cdns_dsi_attach(struct mipi_dsi_host *host,