pwm: sunplus: Make use of devm_pwmchip_alloc() function

This prepares the pwm-sunplus driver to further changes of the pwm core
outlined in the commit introducing devm_pwmchip_alloc(). There is no
intended semantical change and the driver should behave as before.

Link: https://lore.kernel.org/r/192be7e428eff17dd922c9c0d0d168225b89bb34.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-sunplus.c

@@ -43,14 +43,13 @@
 #define SP7021_PWM_NUM			4
 
 struct sunplus_pwm {
-	struct pwm_chip chip;
 	void __iomem *base;
 	struct clk *clk;
 };
 
 static inline struct sunplus_pwm *to_sunplus_pwm(struct pwm_chip *chip)
 {
-	return container_of(chip, struct sunplus_pwm, chip);
+	return pwmchip_get_drvdata(chip);
 }
 
 static int sunplus_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -175,12 +174,14 @@ static void sunplus_pwm_clk_release(void *data)
 static int sunplus_pwm_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct pwm_chip *chip;
 	struct sunplus_pwm *priv;
 	int ret;
 
-	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
+	chip = devm_pwmchip_alloc(dev, SP7021_PWM_NUM, sizeof(*priv));
+	if (IS_ERR(chip))
+		return PTR_ERR(chip);
+	priv = to_sunplus_pwm(chip);
 
 	priv->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->base))
@@ -203,11 +204,9 @@ static int sunplus_pwm_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	priv->chip.dev = dev;
-	priv->chip.ops = &sunplus_pwm_ops;
-	priv->chip.npwm = SP7021_PWM_NUM;
+	chip->ops = &sunplus_pwm_ops;
 
-	ret = devm_pwmchip_add(dev, &priv->chip);
+	ret = devm_pwmchip_add(dev, chip);
 	if (ret < 0)
 		return dev_err_probe(dev, ret, "Cannot register sunplus PWM\n");