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.
Cc: stable@vger.kernel.org Signed-off-by: Lyude cpaul@redhat.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c index cb07da4..ff0b55a 100644 --- 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_device *adev, 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_device *adev, }
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;