[PATCH v2 1/1] drm/bridge: Silence error messages upon probe deferral

[Alexander Stein <alexander.stein@ew.tq-group.com>]

When -EPROBE_DEFER is returned do not raise an error, but silently return
this error instead. Fixes error like this:
[drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc@0/bus@30800000/mipi-dsi@30a00000 to encoder None-34: -517
[drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc@0/bus@30800000/mipi-dsi@30a00000 to encoder None-34: -517

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
---
Changes in v2:
* Adjust the indentation

Considering Laurent's input IMHO -517 should not occur when using component
framework, e.g. drivers/gpu/drm/mcde/mcde_drv.c. This should warrant to only
print an error if it is not deferred probe.
dev_err_probe() sounds reasonable, but this is something which should be done
in drivers. It is also arguable if this message is "hidden" within a debug
statement.

 drivers/gpu/drm/drm_bridge.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index 39e68e45bb124..132180a03c0eb 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -352,13 +352,15 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
 	bridge->encoder = NULL;
 	list_del(&bridge->chain_node);
 
+	if (ret != -EPROBE_DEFER) {
 #ifdef CONFIG_OF
-	DRM_ERROR("failed to attach bridge %pOF to encoder %s: %d\n",
-		  bridge->of_node, encoder->name, ret);
+		DRM_ERROR("failed to attach bridge %pOF to encoder %s: %d\n",
+			bridge->of_node, encoder->name, ret);
 #else
-	DRM_ERROR("failed to attach bridge to encoder %s: %d\n",
-		  encoder->name, ret);
+		DRM_ERROR("failed to attach bridge to encoder %s: %d\n",
+			encoder->name, ret);
 #endif
+	}
 
 	return ret;
 }
-- 
2.34.1