This is a note to let you know that I've just added the patch titled
ACPI / i915: Update the condition to ignore firmware backlight change request
to the 3.16-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:
acpi-i915-update-the-condition-to-ignore-firmware-backlight-change-request.patch
and it can be found in the queue-3.16 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 77076c7aac0184cae2d8a358cf6e6ed1f195fe3f Mon Sep 17 00:00:00 2001
From: Aaron Lu <aaron.lu@xxxxxxxxx>
Date: Fri, 26 Sep 2014 10:30:08 +0800
Subject: ACPI / i915: Update the condition to ignore firmware backlight change request
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Aaron Lu <aaron.lu@xxxxxxxxx>
commit 77076c7aac0184cae2d8a358cf6e6ed1f195fe3f upstream.
Some of the Thinkpads' firmware will issue a backlight change request
through i915 operation region unconditionally on AC plug/unplug, the
backlight level used is arbitrary and thus should be ignored. This is
handled by commit 0b9f7d93ca61 (ACPI / i915: ignore firmware requests
for backlight change). Then there is a Dell laptop whose vendor backlight
interface also makes use of operation region to change backlight level
and with the above commit, that interface no long works. The condition
used to ignore the backlight change request from firmware is thus
changed to: if the vendor backlight interface is not in use and the ACPI
backlight interface is broken, we ignore the requests; oterwise, we keep
processing them.
Fixes: 0b9f7d93ca61 (ACPI / i915: ignore firmware requests for backlight change)
Link: https://lkml.org/lkml/2014/9/23/854
Reported-and-tested-by: Pali Rohár <pali.rohar@xxxxxxxxx>
Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx>
Acked-by: Daniel Vetter <daniel@xxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/intel_opregion.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -395,6 +395,16 @@ int intel_opregion_notify_adapter(struct
return -EINVAL;
}
+/*
+ * If the vendor backlight interface is not in use and ACPI backlight interface
+ * is broken, do not bother processing backlight change requests from firmware.
+ */
+static bool should_ignore_backlight_request(void)
+{
+ return acpi_video_backlight_support() &&
+ !acpi_video_verify_backlight_support();
+}
+
static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -403,11 +413,7 @@ static u32 asle_set_backlight(struct drm
DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
- /*
- * If the acpi_video interface is not supposed to be used, don't
- * bother processing backlight level change requests from firmware.
- */
- if (!acpi_video_verify_backlight_support()) {
+ if (should_ignore_backlight_request()) {
DRM_DEBUG_KMS("opregion backlight request ignored\n");
return 0;
}
Patches currently in stable-queue which might be from aaron.lu@xxxxxxxxx are
queue-3.16/acpi-i915-update-the-condition-to-ignore-firmware-backlight-change-request.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html