3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aaron Lu <aaron.lu@xxxxxxxxx> commit 789eeea128925741e0a105357bebf8855d3bcdee upstream. The ThinkPad X201s has a working ACPI video backlight interface and is shipped before Win8; then there is BIOS update that starts to query _OSI("Windows 2012") and that would make our video module stop creating backlight interface and caused problem for the user. Add it to the DMI table to disable native backlight to fix this problem. Link: https://bugzilla.kernel.org/show_bug.cgi?id=81691 Link: https://bugzilla.kernel.org/show_bug.cgi?id=51231 Reported-and-tested-by: Yves-Alexis Perez <corsac@xxxxxxxxxx> Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/video.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -675,6 +675,14 @@ static struct dmi_system_id video_dmi_ta DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"), }, }, + { + .callback = video_disable_native_backlight, + .ident = "ThinkPad X201s", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"), + }, + }, /* The native backlight controls do not work on some older machines */ { -- 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