From 8675b979b9a4bf86f7bf3b8ed1290391b0b1d593 Mon Sep 17 00:00:00 2001
From: Danny Baumann <dannybaumann@web.de>
Date: Tue, 19 Mar 2013 16:22:52 +0000
Subject: [PATCH] --- yaml --- r: 367607 b: refs/heads/master c:
 994fa63c5b126df6e9f31ef4e09000e2e243234b h: refs/heads/master i:   367605:
 1e06b081696747caa82e15b6636eb4a9844d3bbb   367603:
 1d26946db9701b373f0a458cfde4fc3e27e57035   367599:
 014658f9ce28c213a201e96d3b094e6f42dce769 v: v3

---
 [refs]                     |  2 +-
 trunk/drivers/acpi/video.c | 60 +++++++++++++++++++++++---------------
 2 files changed, 38 insertions(+), 24 deletions(-)

diff --git a/[refs] b/[refs]
index 1517e451aa76..41a64204d680 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2d4128a25206685aaccaf14220c8436b11c6dc01
+refs/heads/master: 994fa63c5b126df6e9f31ef4e09000e2e243234b
diff --git a/trunk/drivers/acpi/video.c b/trunk/drivers/acpi/video.c
index 8522d14972cf..3cdd0471bc63 100644
--- a/trunk/drivers/acpi/video.c
+++ b/trunk/drivers/acpi/video.c
@@ -458,6 +458,31 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 	{}
 };
 
+static unsigned long long
+acpi_video_bqc_value_to_level(struct acpi_video_device *device,
+			      unsigned long long bqc_value)
+{
+	unsigned long long level;
+
+	if (device->brightness->flags._BQC_use_index) {
+		/*
+		 * _BQC returns an index that doesn't account for
+		 * the first 2 items with special meaning, so we need
+		 * to compensate for that by offsetting ourselves
+		 */
+		if (device->brightness->flags._BCL_reversed)
+			bqc_value = device->brightness->count - 3 - bqc_value;
+
+		level = device->brightness->levels[bqc_value + 2];
+	} else {
+		level = bqc_value;
+	}
+
+	level += bqc_offset_aml_bug_workaround;
+
+	return level;
+}
+
 static int
 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 					unsigned long long *level, bool raw)
@@ -480,14 +505,8 @@ acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 				return 0;
 			}
 
-			if (device->brightness->flags._BQC_use_index) {
-				if (device->brightness->flags._BCL_reversed)
-					*level = device->brightness->count
-								 - 3 - (*level);
-				*level = device->brightness->levels[*level + 2];
+			*level = acpi_video_bqc_value_to_level(device, *level);
 
-			}
-			*level += bqc_offset_aml_bug_workaround;
 			for (i = 2; i < device->brightness->count; i++)
 				if (device->brightness->levels[i] == *level) {
 					device->brightness->curr = *level;
@@ -736,24 +755,19 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 
 	br->flags._BQC_use_index = (level == max_level ? 0 : 1);
 
-	if (!br->flags._BQC_use_index) {
+	if (use_bios_initial_backlight) {
+		level = acpi_video_bqc_value_to_level(device, level_old);
 		/*
-		 * Set the backlight to the initial state.
-		 * On some buggy laptops, _BQC returns an uninitialized value
-		 * when invoked for the first time, i.e. level_old is invalid.
-		 * set the backlight to max_level in this case
+		 * On some buggy laptops, _BQC returns an uninitialized
+		 * value when invoked for the first time, i.e.
+		 * level_old is invalid (no matter whether it's a level
+		 * or an index). Set the backlight to max_level in this case.
 		 */
-		if (use_bios_initial_backlight) {
-			for (i = 2; i < br->count; i++)
-				if (level_old == br->levels[i]) {
-					level = level_old;
-					break;
-				}
-		}
-	} else {
-		if (br->flags._BCL_reversed)
-			level_old = (br->count - 1) - level_old;
-		level = br->levels[level_old];
+		for (i = 2; i < br->count; i++)
+			if (level_old == br->levels[i])
+				break;
+		if (i == br->count)
+			level = max_level;
 	}
 
 set_level: