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 <ja...@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);
--
2.25.1
