pwm: jz4740: Make use of devm_pwmchip_alloc() function

This prepares the pwm-jz4740 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.
Acked-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/14a081c097b4e7c7f346ca6557ece8d16ad5749d.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-jz4740.c

@@ -25,14 +25,13 @@ struct soc_info {
 };
 
 struct jz4740_pwm_chip {
-	struct pwm_chip chip;
 	struct regmap *map;
 	struct clk *clk[];
 };
 
 static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip)
 {
-	return container_of(chip, struct jz4740_pwm_chip, chip);
+	return pwmchip_get_drvdata(chip);
 }
 
 static bool jz4740_pwm_can_use_chn(struct pwm_chip *chip, unsigned int channel)
@@ -224,6 +223,7 @@ static const struct pwm_ops jz4740_pwm_ops = {
 static int jz4740_pwm_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct pwm_chip *chip;
 	struct jz4740_pwm_chip *jz;
 	const struct soc_info *info;
 
@@ -231,10 +231,10 @@ static int jz4740_pwm_probe(struct platform_device *pdev)
 	if (!info)
 		return -EINVAL;
 
-	jz = devm_kzalloc(dev, struct_size(jz, clk, info->num_pwms),
-			      GFP_KERNEL);
-	if (!jz)
-		return -ENOMEM;
+	chip = devm_pwmchip_alloc(dev, info->num_pwms, struct_size(jz, clk, info->num_pwms));
+	if (IS_ERR(chip))
+		return PTR_ERR(chip);
+	jz = to_jz4740(chip);
 
 	jz->map = device_node_to_regmap(dev->parent->of_node);
 	if (IS_ERR(jz->map)) {
@@ -242,11 +242,9 @@ static int jz4740_pwm_probe(struct platform_device *pdev)
 		return PTR_ERR(jz->map);
 	}
 
-	jz->chip.dev = dev;
-	jz->chip.ops = &jz4740_pwm_ops;
-	jz->chip.npwm = info->num_pwms;
+	chip->ops = &jz4740_pwm_ops;
 
-	return devm_pwmchip_add(dev, &jz->chip);
+	return devm_pwmchip_add(dev, chip);
 }
 
 static const struct soc_info jz4740_soc_info = {