pwm: hack: ignore duty and period caching

We used to have problem with not properly working failsafe when caching
duty and period values. Because the ardupilot was sending the same
value, the RCIO stopped outputting constant PWM because of failsafe
feature. Therefore we do not cache the values so that this does not happen.

drivers/pwm/core.c

@@ -581,12 +581,6 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
 
 	chip = pwm->chip;
 
-	if (state->period == pwm->state.period &&
-	    state->duty_cycle == pwm->state.duty_cycle &&
-	    state->polarity == pwm->state.polarity &&
-	    state->enabled == pwm->state.enabled)
-		return 0;
-
 	if (chip->ops->apply) {
 		err = chip->ops->apply(chip, pwm, state);
 		if (err)
@@ -627,17 +621,14 @@ int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
 			pwm->state.polarity = state->polarity;
 		}
 
-		if (state->period != pwm->state.period ||
-		    state->duty_cycle != pwm->state.duty_cycle) {
-			err = chip->ops->config(pwm->chip, pwm,
-						state->duty_cycle,
-						state->period);
-			if (err)
-				return err;
+		err = chip->ops->config(pwm->chip, pwm,
+					     state->duty_cycle,
+					     state->period);
+		if (err)
+			return err;
 
-			pwm->state.duty_cycle = state->duty_cycle;
-			pwm->state.period = state->period;
-		}
+		pwm->state.duty_cycle = state->duty_cycle;
+		pwm->state.period = state->period;
 
 		if (state->enabled != pwm->state.enabled) {
 			if (state->enabled) {