diff options
authorVille Syrjälä <>2016-09-13 12:22:19 +0300
committerJani Nikula <>2016-09-14 11:25:05 +0300
commitea54ff4008892b46c7a3e6bc8ab8aaec9d198639 (patch)
parent86dfb76cba284114cf586005cd943eeb6e4f328d (diff)
drm/i915: Ignore OpRegion panel type except on select machinesdrm-intel-fixes-2016-09-15
Turns out commit a05628195a0d ("drm/i915: Get panel_type from OpRegion panel details") has regressed quite a few machines. So it looks like we can't use the panel type from OpRegion on all systems, and yet we absolutely must use it on some specific systems. Despite trying, I was unable to find any automagic way to determine if the OpRegion panel type is respectable or not. The only glimmer of hope I had was bit 8 in the SCIC response, but that turned out to not work either (it was always 0 on both types of systems). So, to fix the regressions without breaking the machine we know to need the OpRegion panel type, let's just add a quirk for this. Only specific machines known to require the OpRegion panel type will therefore use it. Everyone else will fall bck to the VBT panel type. The only known machine so far is a "Conrac GmbH IX45GM2". The PCI subsystem ID on this machine is just a generic 8086:2a42, so of no use. Instead we'll go with a DMI match. I suspect we can now also revert commit aeddda06c1a7 ("drm/i915: Ignore panel type from OpRegion on SKL") but let's leave that to a separate patch. v2: Do the DMI match in the opregion code directly, as dev_priv->quirks gets populated too late Cc: Rob Kramer <> Cc: Martin van Es <> Cc: Andrea Arcangeli <> Cc: Dave Airlie <> Cc: Marco Krüger <> Cc: Sean Greenslade <> Cc: Trudy Tective <> Cc: Robin Müller <> Cc: Alexander Kobel <> Cc: Alexey Shumitsky <> Cc: Emil Andersen Lauridsen <> Cc: Cc: James Hogan <> Cc: James Bottomley <> Cc: References: References: References: Bugzilla: Bugzilla: Bugzilla: Bugzilla: Fixes: a05628195a0d ("drm/i915: Get panel_type from OpRegion panel details") Tested-by: Marco Krüger <> Tested-by: Alexey Shumitsky <> Tested-by: Sean Greenslade <> Tested-by: Emil Andersen Lauridsen <> Tested-by: Robin Müller <> Tested-by: Tested-by: Rob Kramer <> Signed-off-by: Ville Syrjälä <> Link: References: Acked-by: Jani Nikula <> (cherry picked from commit c8ebfad7a063fe665417fa0eeb0da7cfe987d8ed) Signed-off-by: Jani Nikula <>
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index adca262d591a..7acbbbf97833 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -1047,6 +1047,23 @@ err_out:
return err;
+static int intel_use_opregion_panel_type_callback(const struct dmi_system_id *id)
+ DRM_INFO("Using panel type from OpRegion on %s\n", id->ident);
+ return 1;
+static const struct dmi_system_id intel_use_opregion_panel_type[] = {
+ {
+ .callback = intel_use_opregion_panel_type_callback,
+ .ident = "Conrac GmbH IX45GM2",
+ .matches = {DMI_MATCH(DMI_SYS_VENDOR, "Conrac GmbH"),
+ },
+ },
+ { }
intel_opregion_get_panel_type(struct drm_i915_private *dev_priv)
@@ -1073,6 +1090,16 @@ intel_opregion_get_panel_type(struct drm_i915_private *dev_priv)
+ * So far we know that some machined must use it, others must not use it.
+ * There doesn't seem to be any way to determine which way to go, except
+ * via a quirk list :(
+ */
+ if (!dmi_check_system(intel_use_opregion_panel_type)) {
+ DRM_DEBUG_KMS("Ignoring OpRegion panel type (%d)\n", ret - 1);
+ return -ENODEV;
+ }
+ /*
* FIXME On Dell XPS 13 9350 the OpRegion panel type (0) gives us
* low vswing for eDP, whereas the VBT panel type (2) gives us normal
* vswing instead. Low vswing results in some display flickers, so