From a11d342fb89aedec5003d116e7427d43cbba714d Mon Sep 17 00:00:00 2001
From: Stepan Bujnak <stepanbujnak@fastmail.fm>
Date: Wed, 10 Sep 2014 17:44:43 +0200
Subject: [PATCH] ACPI / video: force vendor backlight on Lenovo Ideapad Z570

Lenovo Ideapad 570 is a pre-win8 laptop where not using vendor
backlight causes the backlight controls not to work.

Signed-off-by: Stepan Bujnak <stepanbujnak@fastmail.fm>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 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 c42feb2bacd0..27c43499977a 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -174,6 +174,14 @@ static struct dmi_system_id video_detect_dmi_table[] = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5737"),
 		},
 	},
+	{
+	.callback = video_detect_force_vendor,
+	.ident = "Lenovo IdeaPad Z570",
+	.matches = {
+		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+		DMI_MATCH(DMI_PRODUCT_VERSION, "Ideapad Z570"),
+		},
+	},
 	{ },
 };