diff options
| author | Zhao Yakui <yakui.zhao@intel.com> | 2008-10-17 02:16:41 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-10-22 14:13:28 -0700 |
| commit | 40e24cff25b9c5b12b7f2c8aefecb72bc9c6fd26 (patch) | |
| tree | 3360f5629fe35fccd2a3f6af1c88eacad41c1594 | |
| parent | 116018950eb5201c8e74d04b01b319c8d65d5c5b (diff) | |
ACPI: Ignore _BQC object when registering backlight device
upstream commmit: c2c789057f075022658b38b498755c29c1ba8055
According to acpi spec , the objectes of _BCL and _BCM are required if
integrated LCD is present and supports brightness level and the _BQC is
the optional object. So the _BQC object will be ignored when the backlight
device is registered.
At the same time when there is no _BQC object, the current brightness will be
set to the maximum.
http://bugzilla.kernel.org/show_bug.cgi?id=10206
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/acpi/video.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index d089c4519d4..004da4d0063 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -720,7 +720,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device) kfree(obj); - if (device->cap._BCL && device->cap._BCM && device->cap._BQC && max_level > 0){ + if (device->cap._BCL && device->cap._BCM && max_level > 0) { int result; static int count = 0; char *name; @@ -732,7 +732,17 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device) device->backlight = backlight_device_register(name, NULL, device, &acpi_backlight_ops); device->backlight->props.max_brightness = device->brightness->count-3; - device->backlight->props.brightness = acpi_video_get_brightness(device->backlight); + /* + * If there exists the _BQC object, the _BQC object will be + * called to get the current backlight brightness. Otherwise + * the brightness will be set to the maximum. + */ + if (device->cap._BQC) + device->backlight->props.brightness = + acpi_video_get_brightness(device->backlight); + else + device->backlight->props.brightness = + device->backlight->props.max_brightness; backlight_update_status(device->backlight); kfree(name); |