pwm: rcar: Prepare removing pwm_chip from driver data

This prepares the driver for further changes that will drop struct
pwm_chip chip from struct rcar_pwm_chip. Use the pwm_chip as driver
data instead of the rcar_pwm_chip to get access to the pwm_chip in
the .remove() callbacks without using rcar_pwm->chip.

Link: https://lore.kernel.org/r/e588e3ccdd0ac1c9c3f3a79b3e52112f83f9d71c.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-rcar.c

@@ -202,6 +202,7 @@ static const struct pwm_ops rcar_pwm_ops = {
 
 static int rcar_pwm_probe(struct platform_device *pdev)
 {
+	struct pwm_chip *chip;
 	struct rcar_pwm_chip *rcar_pwm;
 	int ret;
 
@@ -219,15 +220,16 @@ static int rcar_pwm_probe(struct platform_device *pdev)
 		return PTR_ERR(rcar_pwm->clk);
 	}
 
-	platform_set_drvdata(pdev, rcar_pwm);
+	chip = &rcar_pwm->chip;
+	chip->dev = &pdev->dev;
+	chip->ops = &rcar_pwm_ops;
+	chip->npwm = 1;
 
-	rcar_pwm->chip.dev = &pdev->dev;
-	rcar_pwm->chip.ops = &rcar_pwm_ops;
-	rcar_pwm->chip.npwm = 1;
+	platform_set_drvdata(pdev, chip);
 
 	pm_runtime_enable(&pdev->dev);
 
-	ret = pwmchip_add(&rcar_pwm->chip);
+	ret = pwmchip_add(chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed to register PWM chip: %d\n", ret);
 		pm_runtime_disable(&pdev->dev);
@@ -239,9 +241,9 @@ static int rcar_pwm_probe(struct platform_device *pdev)
 
 static void rcar_pwm_remove(struct platform_device *pdev)
 {
-	struct rcar_pwm_chip *rcar_pwm = platform_get_drvdata(pdev);
+	struct pwm_chip *chip = platform_get_drvdata(pdev);
 
-	pwmchip_remove(&rcar_pwm->chip);
+	pwmchip_remove(chip);
 
 	pm_runtime_disable(&pdev->dev);
 }