On Tue, 22 Dec 2015 17:38:00 +0000
Liviu Dudau [off-list ref] wrote:

quoted

On Fri, Nov 20, 2015 at 02:22:03PM +0000, Liviu Dudau wrote:

quoted

Hello,

This is v2 of the patchset trying to make drm_of_component_probe() cope with finding
both local crtc ports and remote encoder ones. Heiko St?bner was nice enough to test
an earlier version that was patched following Russell's suggestions on rk3288, but
I haven't seen any reports from iMX or Armada users.

Changelog:
 v2: Updated the drm_of_component_probe() comment to explain why the reference count
     is not dropped. Fixed the compare_port() function for rockchip as described by
     Russell.
 v1: Original submission. http://lists.freedesktop.org/archives/dri-devel/2015-November/094546.html

Gentle ping, this has now been tested by Rockchip people and fixes the earlier version
that had to be reverted in mainline. Can it be included in the -next somewhere?

Hi Liviu,

Sorry for being a bit late.

I wanted to use drm_of_component_probe() for a new DRM driver, but I
could not find any way to do it: you add the "ports" nodes as
components while, usually, the components are the device nodes
themselves.

With this simple patch:

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 493c05c..dbd2921 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c

@@ -101,7 +101,7 @@ int drm_of_component_probe(struct device *dev,
 			continue;
 		}
 
-		component_match_add(dev, &match, compare_of, port);
+		component_match_add(dev, &match, compare_of, port->parent);
 		of_node_put(port);
 	}
 

everything is easy, my DT being like:

	de_controller {
		...
		ports = <&lcd0_p>;
	};

	lcd_controller {
		...
		lcd0_p: port {
			lcd0_ep: endpoint {
				remote-endpoint = <&hdmi_ep>;
			};
		};
	};

What was the reason to keep the "ports" node instead of the device?