Dell Latitude 3160 does not have keyboard backlight, but there is a sysfs interface for it, which does nothing at all. KBD_LED_OFF_TOKEN is the only token can be found. Since it doesn't have KBD_LED_ON_TOKEN or KBD_LED_AUTO_*_TOKEN, it should be safe to assume it does not support keyboard backlight. Reports keyboard backlight is supported only when tokens other than KBD_LED_OFF_TOKEN can be found. Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> --- drivers/platform/x86/dell-laptop.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c index ec202094bd50..743d7ce8c0c8 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -1510,7 +1510,11 @@ static void kbd_init(void) ret = kbd_init_info(); kbd_init_tokens(); - if (kbd_token_bits != 0 || ret == 0) + /* + * If KBD_LED_OFF_TOKEN is the only token, + * consider there is no keyboard backlight. + */ + if ((kbd_token_bits & ~BIT(5)) != 0 || ret == 0) kbd_led_present = true; } -- 2.13.1
