From 129ff8f8d58297b04f47b5d6fad81aa2d08404e1 Mon Sep 17 00:00:00 2001
From: Zhang Rui <rui.zhang@intel.com>
Date: Tue, 4 Dec 2012 23:30:19 +0100
Subject: [PATCH] ACPI / video: ignore BIOS initial backlight value for HP
 Folio 13-2000

Or else the laptop will boot with a dimmed screen.

References: https://bugzilla.kernel.org/show_bug.cgi?id=51141
Tested-by: Stefan Nagy <public@stefan-nagy.at>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/video.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 0230cb6cbb3a..ac9a69cd45f5 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -389,6 +389,12 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d)
 	return 0;
 }
 
+static int video_ignore_initial_backlight(const struct dmi_system_id *d)
+{
+	use_bios_initial_backlight = 0;
+	return 0;
+}
+
 static struct dmi_system_id video_dmi_table[] __initdata = {
 	/*
 	 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@@ -433,6 +439,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 		},
 	},
+	{
+	 .callback = video_ignore_initial_backlight,
+	 .ident = "HP Folio 13-2000",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
+		},
+	},
 	{}
 };
 
-- 
GitLab