pwm: stm32: Prepare removing pwm_chip from driver data

This prepares the driver for further changes that will drop struct
pwm_chip chip from struct stm32_pwm. Use the pwm_chip as driver
data instead of the stm32_pwm to get access to the pwm_chip in
stm32_pwm_suspend() without using priv->chip.

Link: https://lore.kernel.org/r/3db96cd915d9d8fc350a7193c0d55dd109b1f035.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-stm32.c

@@ -630,6 +630,7 @@ static int stm32_pwm_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
+	struct pwm_chip *chip;
 	struct stm32_pwm *priv;
 	unsigned int num_enabled;
 	unsigned int i;
@@ -638,6 +639,7 @@ static int stm32_pwm_probe(struct platform_device *pdev)
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
+	chip = &priv->chip;
 
 	mutex_init(&priv->lock);
 	priv->regmap = ddata->regmap;
@@ -653,37 +655,38 @@ static int stm32_pwm_probe(struct platform_device *pdev)
 
 	stm32_pwm_detect_complementary(priv);
 
-	priv->chip.dev = dev;
-	priv->chip.ops = &stm32pwm_ops;
-	priv->chip.npwm = stm32_pwm_detect_channels(priv, &num_enabled);
+	chip->dev = dev;
+	chip->ops = &stm32pwm_ops;
+	chip->npwm = stm32_pwm_detect_channels(priv, &num_enabled);
 
 	/* Initialize clock refcount to number of enabled PWM channels. */
 	for (i = 0; i < num_enabled; i++)
 		clk_enable(priv->clk);
 
-	ret = devm_pwmchip_add(dev, &priv->chip);
+	ret = devm_pwmchip_add(dev, chip);
 	if (ret < 0)
 		return ret;
 
-	platform_set_drvdata(pdev, priv);
+	platform_set_drvdata(pdev, chip);
 
 	return 0;
 }
 
 static int stm32_pwm_suspend(struct device *dev)
 {
-	struct stm32_pwm *priv = dev_get_drvdata(dev);
+	struct pwm_chip *chip = dev_get_drvdata(dev);
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
 	unsigned int i;
 	u32 ccer, mask;
 
 	/* Look for active channels */
 	ccer = active_channels(priv);
 
-	for (i = 0; i < priv->chip.npwm; i++) {
+	for (i = 0; i < chip->npwm; i++) {
 		mask = TIM_CCER_CC1E << (i * 4);
 		if (ccer & mask) {
 			dev_err(dev, "PWM %u still in use by consumer %s\n",
-				i, priv->chip.pwms[i].label);
+				i, chip->pwms[i].label);
 			return -EBUSY;
 		}
 	}
@@ -693,7 +696,8 @@ static int stm32_pwm_suspend(struct device *dev)
 
 static int stm32_pwm_resume(struct device *dev)
 {
-	struct stm32_pwm *priv = dev_get_drvdata(dev);
+	struct pwm_chip *chip = dev_get_drvdata(dev);
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
 	int ret;
 
 	ret = pinctrl_pm_select_default_state(dev);