sony-laptop: report failures on setting LCD brightness

Check if we were successful in setting the requested brightness and
report failure in that case.

Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/platform/x86/sony-laptop.c b/drivers/platform/x86/sony-laptop.c
index 8f709aec4da0..9d80ae4e6be6 100644
--- a/drivers/platform/x86/sony-laptop.c
+++ b/drivers/platform/x86/sony-laptop.c
@@ -966,9 +966,10 @@ static int sony_nc_update_status_ng(struct backlight_device *bd)
         int *handle = (int *)bl_get_data(bd);
 
         value = bd->props.brightness;
-        sony_call_snc_handle(*handle, 0x0100 | (value << 16), &result);
+        if (sony_call_snc_handle(*handle, 0x0100 | (value << 16), &result))
+                return -EIO;
 
-        return sony_nc_get_brightness_ng(bd);
+        return value;
 }
 
 static const struct backlight_ops sony_backlight_ops = {