On the Yoga 13 the backlight control doesn't work via ACPI. (And doesn't work either with the low-level platform driver ideapad_laptop; but works correctly via the intel video driver). This patch hence adds the Yoga 13 to the ACPI video detect blacklist, to make sure the broken ACPI backlight device is never exposed to userspace. Note that this appears unrelated to the Windows 8 backlight issues tracked here: https://bugzilla.kernel.org/show_bug.cgi?id=51231 https://bugzilla.kernel.org/show_bug.cgi?id=60682 The Yoga's ACPI backlight controls work neither with nor without acpi_osi="!Windows 2012" on the kernel command line. It appears that backlight control via the EC simply is not available at all, regardless whether done via ACPI or via the vendor driver. Signed-off-by: Lennart Poettering <lennart@xxxxxxxxxxxxxx> --- drivers/acpi/video_detect.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 940edbf..a88e8f7 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -168,6 +168,14 @@ static struct dmi_system_id video_detect_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"), }, }, + { + .callback = video_detect_force_vendor, + .ident = "Lenovo Yoga 13", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"), + }, + }, { }, }; -- 1.8.3.1 Lennart -- Lennart Poettering - Red Hat, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html