The output port endpoints can be connected to USB-C connectors.
Running drm_of_find_panel_or_bridge() with such endpoints leads to
a continuous return value of -EPROBE_DEFER, even though there is
no panel present.
To avoid this, check for the existence of a "mode-switch" property in
the port endpoint, and skip panel registration completely if so.
Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
Changes in v15:
- Collect review tag
Changes in v14:
- Collect review tag
Changes in v13:
- Use the new typec_mode_switch_node_count helper
Changes in v12:
- Updated to use fwnode_for_each_typec_mode_switch macro
- Dropped collected tags
Changes in v10:
- Collected Reviewed-by and Tested-by tags
Changes in v6:
- New in v6
drivers/gpu/drm/bridge/analogix/anx7625.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 6846199a2ee1..3f6bf7674d32 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1648,7 +1648,8 @@ static int anx7625_get_swing_setting(struct device *dev,
static int anx7625_parse_dt(struct device *dev,
struct anx7625_platform_data *pdata)
{
- struct device_node *np = dev->of_node, *ep0;
+ struct device_node *np = dev->of_node, *ep0, *port_node;
+ unsigned int count;
int bus_type, mipi_lanes;
anx7625_get_swing_setting(dev, pdata);
@@ -1687,6 +1688,15 @@ static int anx7625_parse_dt(struct device *dev,
if (of_property_read_bool(np, "analogix,audio-enable"))
pdata->audio_en = 1;
+ /*
+ * Don't bother finding a panel if a Type-C `mode-switch` property is
+ * present in one of the endpoints in the output port.
+ */
+ port_node = of_graph_get_port_by_id(np, 1);
+ count = typec_mode_switch_node_count(&port_node->fwnode);
+ if (count)
+ return 0;
+
pdata->panel_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
if (IS_ERR(pdata->panel_bridge)) {
if (PTR_ERR(pdata->panel_bridge) == -ENODEV) {
--
2.40.0.348.gf938b09366-goog
