thermal: intel: int340x: Improve int340x_thermal_set_trip_temp()

Instead of using snprintf() to populate the ACPI object name in
int340x_thermal_set_trip_temp(), use an appropriate initializer
and make the function fail if its trip argument is greater than 9,
because ACPI object names can only be 4 characters long and it does
not make sense to even try to evaluate objects with longer names (that
argument is guaranteed to be non-negative, because it comes from the
thermal code that will not pass negative trip numbers to zone
callbacks).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>

diff --git a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
index 0e622bb..0066596 100644 (file)
--- a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
+++ b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
@@ -42,10 +42,12 @@ static int int340x_thermal_set_trip_temp(struct thermal_zone_device *zone,
                                         int trip, int temp)
 {
        struct int34x_thermal_zone *d = zone->devdata;
+       char name[] = {'P', 'A', 'T', '0' + trip, '\0'};
        acpi_status status;
-       char name[10];
 
-       snprintf(name, sizeof(name), "PAT%d", trip);
+       if (trip > 9)
+               return -EINVAL;
+
        status = acpi_execute_simple_method(d->adev->handle, name,
                                            millicelsius_to_deci_kelvin(temp));
        if (ACPI_FAILURE(status))