Patch "drm/amdgpu: Poll for both connect/disconnect on analog connectors" has been added to the 4.4-stable tree

Patch "drm/amdgpu: Poll for both connect/disconnect on analog connectors" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    drm/amdgpu: Poll for both connect/disconnect on analog connectors

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-amdgpu-poll-for-both-connect-disconnect-on-analog-connectors.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From b636a1b3d624b49b23cc1be2f9f6bcbb89aca855 Mon Sep 17 00:00:00 2001
From: Lyude <cpaul@redhat.com>
Date: Fri, 24 Jun 2016 17:54:32 -0400
Subject: drm/amdgpu: Poll for both connect/disconnect on analog connectors

From: Lyude <cpaul@redhat.com>

commit b636a1b3d624b49b23cc1be2f9f6bcbb89aca855 upstream.

DRM_CONNECTOR_POLL_CONNECT only enables polling for connections, not
disconnections. Because of this, we end up losing hotplug polling for
analog connectors once they get connected.

Easy way to reproduce:
 - Grab a machine with an AMD GPU and a VGA port
 - Plug a monitor into the VGA port, wait for it to update the connector
   from disconnected to connected
 - Disconnect the monitor on VGA, a hotplug event is never sent for the
   removal of the connector.

Originally, only using DRM_CONNECTOR_POLL_CONNECT might have been a good
idea since doing VGA polling can sometimes result in having to mess with
the DAC voltages to figure out whether or not there's actually something
there since VGA doesn't have HPD. Doing this would have the potential of
showing visible artifacts on the screen every time we ran a poll while a
VGA display was connected. Luckily, amdgpu_vga_detect() only resorts to
this sort of polling if the poll is forced, and DRM's polling helper
doesn't force it's polls.

Additionally, this removes some assignments to connector->polled that
weren't actually doing anything.

Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
@@ -1690,7 +1690,6 @@ amdgpu_connector_add(struct amdgpu_devic
 						   DRM_MODE_SCALE_NONE);
 			/* no HPD on analog connectors */
 			amdgpu_connector->hpd.hpd = AMDGPU_HPD_NONE;
-			connector->polled = DRM_CONNECTOR_POLL_CONNECT;
 			connector->interlace_allowed = true;
 			connector->doublescan_allowed = true;
 			break;
@@ -1893,8 +1892,10 @@ amdgpu_connector_add(struct amdgpu_devic
 	}
 
 	if (amdgpu_connector->hpd.hpd == AMDGPU_HPD_NONE) {
-		if (i2c_bus->valid)
-			connector->polled = DRM_CONNECTOR_POLL_CONNECT;
+		if (i2c_bus->valid) {
+			connector->polled = DRM_CONNECTOR_POLL_CONNECT |
+			                    DRM_CONNECTOR_POLL_DISCONNECT;
+		}
 	} else
 		connector->polled = DRM_CONNECTOR_POLL_HPD;
 


Patches currently in stable-queue which might be from cpaul@redhat.com are

queue-4.4/drm-amdgpu-poll-for-both-connect-disconnect-on-analog-connectors.patch
queue-4.4/drm-radeon-poll-for-both-connect-disconnect-on-analog-connectors.patch
queue-4.4/drm-amdgpu-disable-rpm-helpers-while-reprobing-connectors-on-resume.patch