pwm: spear: Implement .apply() callback

Just using the previous callbacks to implment a similar procedure as the
legacy handling in the core.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-spear.c

@@ -75,7 +75,7 @@ static inline void spear_pwm_writel(struct spear_pwm_chip *chip,
 }
 
 static int spear_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
-			    int duty_ns, int period_ns)
+			    u64 duty_ns, u64 period_ns)
 {
 	struct spear_pwm_chip *pc = to_spear_pwm_chip(chip);
 	u64 val, div, clk_rate;
@@ -163,10 +163,35 @@ static void spear_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	clk_disable(pc->clk);
 }
 
+static int spear_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			   const struct pwm_state *state)
+{
+	int err;
+
+	if (state->polarity != PWM_POLARITY_NORMAL)
+		return -EINVAL;
+
+	if (!state->enabled) {
+		if (pwm->state.enabled)
+			spear_pwm_disable(chip, pwm);
+		return 0;
+	}
+
+	if (state->period != pwm->state.period ||
+	    state->duty_cycle != pwm->state.duty_cycle) {
+		err = spear_pwm_config(chip, pwm, state->duty_cycle, state->period);
+		if (err)
+			return err;
+	}
+
+	if (!pwm->state.enabled)
+		return spear_pwm_enable(chip, pwm);
+
+	return 0;
+}
+
 static const struct pwm_ops spear_pwm_ops = {
-	.config = spear_pwm_config,
-	.enable = spear_pwm_enable,
-	.disable = spear_pwm_disable,
+	.apply = spear_pwm_apply,
 	.owner = THIS_MODULE,
 };