[PATCH v2 06/10] drm/bridge: tc358775: Get bridge data lanes instead of the DSI host lanes

[Tony Lindgren <tony@atomide.com>]

The current code assumes the data-lanes property is configured on the
DSI host side instead of the bridge side, and assumes DSI host endpoint 1.

Let's standardize on what the other bridge drivers are doing and parse the
data-lanes property for the bridge. Only if data-lanes property is not found,
let's be nice and also check the DSI host for old dtb in use and warn.

Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/gpu/drm/bridge/tc358775.c | 25 +++++++++++--------------
 1 file changed, 11 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/tc358775.c b/drivers/gpu/drm/bridge/tc358775.c
--- a/drivers/gpu/drm/bridge/tc358775.c
+++ b/drivers/gpu/drm/bridge/tc358775.c
@@ -525,27 +525,24 @@ tc_mode_valid(struct drm_bridge *bridge,
 static int tc358775_parse_dt(struct device_node *np, struct tc_data *tc)
 {
 	struct device_node *endpoint;
-	struct device_node *parent;
 	struct device_node *remote;
 	int dsi_lanes = -1;
 
-	/*
-	 * To get the data-lanes of dsi, we need to access the dsi0_out of port1
-	 *  of dsi0 endpoint from bridge port0 of d2l_in
-	 */
 	endpoint = of_graph_get_endpoint_by_regs(tc->dev->of_node,
 						 TC358775_DSI_IN, -1);
-	if (endpoint) {
-		/* dsi0_out node */
-		parent = of_graph_get_remote_port_parent(endpoint);
-		of_node_put(endpoint);
-		if (parent) {
-			/* dsi0 port 1 */
-			dsi_lanes = drm_of_get_data_lanes_count_ep(parent, 1, -1, 1, 4);
-			of_node_put(parent);
-		}
+	dsi_lanes = drm_of_get_data_lanes_count(endpoint, 1, 4);
+
+	/* Quirk old dtb: Use data lanes from the DSI host side instead of bridge */
+	if (dsi_lanes == -EINVAL || dsi_lanes == -ENODEV) {
+		remote = of_graph_get_remote_endpoint(endpoint);
+		dsi_lanes = drm_of_get_data_lanes_count(remote, 1, 4);
+		of_node_put(remote);
+		if (dsi_lanes >= 1)
+			dev_warn(tc->dev, "missing dsi-lanes property for the bridge\n");
 	}
 
+	of_node_put(endpoint);
+
 	if (dsi_lanes < 0)
 		return dsi_lanes;
 
-- 
2.43.0