ACPI: thinkpad-acpi: do not arm fan watchdog if it would not work

Do not enable/rearm the fan control safety watchdog if we would not be able
to do anything to the fan anyway.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 7dc3a220619..f824259fa61 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -3197,6 +3197,9 @@ static void fan_watchdog_reset(void)
 {
         static int fan_watchdog_active = 0;
 
+        if (fan_control_access_mode == TPACPI_FAN_WR_NONE)
+                return;
+
         if (fan_watchdog_active)
                 cancel_delayed_work(&fan_watchdog_task);