Acer-WMI: fingers off backlight if video.ko is serving this functionality

Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/misc/acer-wmi.c b/drivers/misc/acer-wmi.c
index 0532a2de2ce4..94c9f911824e 100644
--- a/drivers/misc/acer-wmi.c
+++ b/drivers/misc/acer-wmi.c
@@ -1297,6 +1297,12 @@ static int __init acer_wmi_init(void)
 
         set_quirks();
 
+        if (!acpi_video_backlight_support() && has_cap(ACER_CAP_BRIGHTNESS)) {
+                interface->capability &= ~ACER_CAP_BRIGHTNESS;
+                printk(ACER_INFO "Brightness must be controlled by "
+                       "generic video driver\n");
+        }
+
         if (platform_driver_register(&acer_platform_driver)) {
                 printk(ACER_ERR "Unable to register platform driver.\n");
                 goto error_platform_register;