@@ -295,6 +295,17 @@ void intel_panel_disable_backlight(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
+ /*
+ * Do not disable backlight on the vgaswitcheroo path. When switching
+ * away from i915, the other client may depend on i915 to handle the
+ * backlight. This will leave the backlight on unnecessarily when
+ * another client is not activated.
+ */
+ if (dev->switch_power_state == DRM_SWITCH_POWER_CHANGING) {
+ DRM_DEBUG_DRIVER("Skipping backlight disable on vga switch\n");
+ return;
+ }
+
dev_priv->backlight_enabled = false;
intel_panel_actually_set_backlight(dev, 0);
This is a note to let you know that I have just added a patch titled drm/i915: do not disable backlight on vgaswitcheroo switch off to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.7. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From aefeee9d8628035ad8fb0918b772c061f2824aa4 Mon Sep 17 00:00:00 2001 From: Jani Nikula <jani.nikula@intel.com> Date: Thu, 25 Jul 2013 14:31:30 +0300 Subject: drm/i915: do not disable backlight on vgaswitcheroo switch off commit 3f577573cd5482a32f85bd131e52f7cb4b9ac518 upstream. On muxed systems, the other vgaswitcheroo client may depend on i915 to handle the backlight. We began switching off the backlight since commit a261b246ebd552fd5d5a8ed84cc931bb821c427f Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Thu Jul 26 19:21:47 2012 +0200 drm/i915: disable all crtcs at suspend time breaking backlight on discreet graphics in (some) muxed systems. Keep the backlight on when the state is changed through vgaswitcheroo. Note: The alternative would be to add a quirk table to achieve the same based on system identifiers, but AFAICS it would asymptotically approach effectively the same as this patch as more IDs are added, but with the maintenance burden of the quirk table. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=55311 Tested-by: Fede <fedevx@yahoo.com> Tested-by: Aximab <laurent.debian@gmail.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59785 Tested-by: sfievet <sebastien.fievet@free.fr> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> [ kamal: backport to 3.8 (context) ] Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/gpu/drm/i915/intel_panel.c | 11 +++++++++++ 1 file changed, 11 insertions(+) -- 1.8.1.2