diff options
| author | Danny Baumann <dannybaumann@web.de> | 2013-03-19 16:22:52 +0000 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-03-25 00:26:55 +0100 |
| commit | 994fa63c5b126df6e9f31ef4e09000e2e243234b (patch) | |
| tree | b6214bc68418cae8935248c4d997318702c98daf /drivers | |
| parent | 2d4128a25206685aaccaf14220c8436b11c6dc01 (diff) | |
| download | linux-994fa63c5b126df6e9f31ef4e09000e2e243234b.tar.bz2 | |
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')
| -rw-r--r-- | drivers/acpi/video.c | 60 |
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: |