drm_of_find_panel_or_bridge can lookup panel or bridge for a given node based on the OF graph port and endpoint and it fails to use if the given node has a child panel or bridge.
This patch add support to lookup that given node has child panel or bridge however that child node cannot be a 'port'.
Examples OF graph representation of DSI host, which doesn't have 'ports'
dsi { compatible = "allwinner,sun6i-a31-mipi-dsi"; #address-cells = <1>; #size-cells = <0>;
port { dsi_in_tcon0: endpoint { remote-endpoint = <tcon0_out_dsi>; };
panel@0 { reg = <0>; }; };
dsi { compatible = "allwinner,sun6i-a31-mipi-dsi"; #address-cells = <1>; #size-cells = <0>;
port { dsi_in_tcon0: endpoint { remote-endpoint = <tcon0_out_dsi>; };
bridge@0 { reg = <0>;
ports { #address-cells = <1>; #size-cells = <0>;
bridge_out: port@1 { reg = <1>;
bridge_out_panel: endpoint { remote-endpoint = <&panel_out_bridge>; }; }; }; }; };
dsi0 { compatible = "ste,mcde-dsi"; #address-cells = <1>; #size-cells = <0>;
panel@0 { reg = <0>; }; };
Signed-off-by: Jagan Teki jagan@amarulasolutions.com --- drivers/gpu/drm/drm_of.c | 36 ++++++++++++++++++++++++++---------- 1 file changed, 26 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c index 59d368ea006b..1c4cb809d7bc 100644 --- a/drivers/gpu/drm/drm_of.c +++ b/drivers/gpu/drm/drm_of.c @@ -249,18 +249,34 @@ int drm_of_find_panel_or_bridge(const struct device_node *np, if (panel) *panel = NULL;
- /* - * of_graph_get_remote_node() produces a noisy error message if port - * node isn't found and the absence of the port is a legit case here, - * so at first we silently check whether graph presents in the - * device-tree node. + /** + * Some OF graphs don't require 'ports' to represent the next output + * instead, it simply adds a child node on a given parent node. + * Lookup that child node for a given parent however that child + * cannot be a 'port'. + * + * Add precedence to lookup non port child as of_graph_get_remote_node() + * returns valid even if OF graph has 'port' but that OF graph remote + * node is not register panel or bridge. */ - if (!of_graph_is_present(np)) - return -ENODEV; + if (!of_get_child_by_name(np, "ports")) { + remote = of_get_non_port_child(np); + if (!remote) + return -ENODEV; + } else { + /* + * of_graph_get_remote_node() produces a noisy error message if port + * node isn't found and the absence of the port is a legit case here, + * so at first we silently check whether graph presents in the + * device-tree node. + */ + if (!of_graph_is_present(np)) + return -ENODEV;
- remote = of_graph_get_remote_node(np, port, endpoint); - if (!remote) - return -ENODEV; + remote = of_graph_get_remote_node(np, port, endpoint); + if (!remote) + return -ENODEV; + }
if (panel) { *panel = of_drm_find_panel(remote);