ACPI: blacklist win8 OSI for buggy laptops
authorFelipe Contreras <felipe.contreras@gmail.com>
Sun, 25 Aug 2013 17:37:33 +0000 (12:37 -0500)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Sun, 25 Aug 2013 19:31:12 +0000 (21:31 +0200)
commit94fb9823a7c478bf88b99b8da4fc3e540608ece5
treeca96e5e955350b2669515a97767f5ae807ebc2f2
parentcb7a386c6c25e85c2710cdb1a498a73794cda660
ACPI: blacklist win8 OSI for buggy laptops

Since v3.7 the acpi backlight driver doesn't work correctly in several
machines because ACPI code has different code for Windows 8, and the
rest.

The commit ea45ea7 (in v3.11-rc2) tried to fix this problem by using the
intel backlight driver, however it introduced several other issues in
different machines.

This patch fixes both regressions by blacklisting the win8 OSI, so we
are back to v3.6 behavior, and it should remain that way until the intel
backlight driver is fixed.

Since v3.7, users have been forced to fix the initial regression by
modifying the boot arguments (acpi_osi="!Windows 2012").

Once the Intel backlight driver works correctly for all machines, this
blacklist can be removed and that driver can be used instead.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60682
Reported-by: Danny Baumann <dannybaumann@web.de>
Reported-by: Philipp Richter <richterphilipp.pops@gmail.com>
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/blacklist.c