asus-wmi: handle "unknown status" bit
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index d0f0931e..39ce3c1 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -92,6 +92,7 @@
/* DSTS masks */
#define ASUS_WMI_DSTS_STATUS_BIT 0x00000001
+#define ASUS_WMI_DSTS_UNKNOWN_BIT 0x00000002
#define ASUS_WMI_DSTS_PRESENCE_BIT 0x00010000
#define ASUS_WMI_DSTS_BRIGHTNESS_MASK 0x000000FF
#define ASUS_WMI_DSTS_MAX_BRIGTH_MASK 0x0000FF00
@@ -270,6 +271,11 @@
if (!(retval & ASUS_WMI_DSTS_PRESENCE_BIT))
return -ENODEV;
+ if (mask == ASUS_WMI_DSTS_STATUS_BIT) {
+ if (retval & ASUS_WMI_DSTS_UNKNOWN_BIT)
+ return -ENODEV;
+ }
+
return retval & mask;
}