[RFC PATCH 10/17] drm: bridge: samsung-dsim: Update the of_node for port(s)

[Jagan Teki]

Existing bridge driver is able to find the panel or bridge
if of_node isn't a port(s). This is how the exynos dsi
node handling has been done so far.

However in order to make use of this bridge in other or
new supported platforms like i.MX8MM it is required to
have a port based of_node.

So, this patch will check if node is a port based and
then update of_node.

This way we can support the platforms which are using
legacy or new DSI bindings.

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
 drivers/gpu/drm/bridge/samsung-dsim.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 627580abd6df..2222c27feffd 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -226,6 +226,11 @@ enum samsung_dsim_transfer_type {
 	EXYNOS_DSI_RX,
 };
 
+enum {
+	DSI_PORT_IN,
+	DSI_PORT_OUT
+};
+
 struct samsung_dsim_transfer {
 	struct list_head list;
 	struct completion completed;
@@ -1436,6 +1441,15 @@ static int samsung_dsim_panel_or_bridge(struct samsung_dsim *dsi,
 {
 	struct drm_bridge *panel_bridge;
 	struct drm_panel *panel;
+	struct device_node *remote;
+
+	if (of_graph_is_present(node)) {
+		remote = of_graph_get_remote_node(node, DSI_PORT_OUT, 0);
+		if (!remote)
+			return -ENODEV;
+
+		node = remote;
+	}
 
 	panel_bridge = of_drm_find_bridge(node);
 	if (!panel_bridge) {
@@ -1579,11 +1593,6 @@ static int samsung_dsim_of_read_u32(const struct device_node *np,
 	return ret;
 }
 
-enum {
-	DSI_PORT_IN,
-	DSI_PORT_OUT
-};
-
 static int samsung_dsim_parse_dt(struct samsung_dsim *dsi)
 {
 	struct device *dev = dsi->dev;
-- 
2.25.1