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authorDanny Baumann <dannybaumann@web.de>2013-03-19 16:22:52 +0000
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2013-03-25 00:26:55 +0100
commit994fa63c5b126df6e9f31ef4e09000e2e243234b (patch)
treeb6214bc68418cae8935248c4d997318702c98daf /drivers/acpi/video.c
parent2d4128a25206685aaccaf14220c8436b11c6dc01 (diff)
ACPI / video: Fix applying indexed initial brightness value.
The value initially read via _BQC also needs to be offset by 2 to compensate for the first 2 special items in _BCL. Introduce a helper function that does the BQC-value-to-level conversion in order to not needlessly duplicate code. Signed-off-by: Danny Baumann <dannybaumann@web.de> Reviewed-by: Aaron Lu <aaron.lu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/video.c')
-rw-r--r--drivers/acpi/video.c60
1 files changed, 37 insertions, 23 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 8522d14972cf..3cdd0471bc63 100644
--- a/drivers/acpi/video.c
+++ b/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: