pwm: lpss: Make use of pwmchip_parent() accessor

struct pwm_chip::dev is about to change. To not have to touch this
driver in the same commit as struct pwm_chip::dev, use the accessor
function provided for exactly this purpose.

Link: https://lore.kernel.org/r/77617ba84bed7807a05779109432a292dd79f72f.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-lpss.c

@@ -106,7 +106,7 @@ static int pwm_lpss_wait_for_update(struct pwm_device *pwm)
 	 */
 	err = readl_poll_timeout(addr, val, !(val & PWM_SW_UPDATE), 40, ms);
 	if (err)
-		dev_err(pwm->chip->dev, "PWM_SW_UPDATE was not cleared\n");
+		dev_err(pwmchip_parent(pwm->chip), "PWM_SW_UPDATE was not cleared\n");
 
 	return err;
 }
@@ -114,7 +114,7 @@ static int pwm_lpss_wait_for_update(struct pwm_device *pwm)
 static inline int pwm_lpss_is_updating(struct pwm_device *pwm)
 {
 	if (pwm_lpss_read(pwm) & PWM_SW_UPDATE) {
-		dev_err(pwm->chip->dev, "PWM_SW_UPDATE is still set, skipping update\n");
+		dev_err(pwmchip_parent(pwm->chip), "PWM_SW_UPDATE is still set, skipping update\n");
 		return -EBUSY;
 	}
 
@@ -190,16 +190,16 @@ static int pwm_lpss_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	if (state->enabled) {
 		if (!pwm_is_enabled(pwm)) {
-			pm_runtime_get_sync(chip->dev);
+			pm_runtime_get_sync(pwmchip_parent(chip));
 			ret = pwm_lpss_prepare_enable(lpwm, pwm, state);
 			if (ret)
-				pm_runtime_put(chip->dev);
+				pm_runtime_put(pwmchip_parent(chip));
 		} else {
 			ret = pwm_lpss_prepare_enable(lpwm, pwm, state);
 		}
 	} else if (pwm_is_enabled(pwm)) {
 		pwm_lpss_write(pwm, pwm_lpss_read(pwm) & ~PWM_ENABLE);
-		pm_runtime_put(chip->dev);
+		pm_runtime_put(pwmchip_parent(chip));
 	}
 
 	return ret;
@@ -213,7 +213,7 @@ static int pwm_lpss_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 	unsigned long long base_unit, freq, on_time_div;
 	u32 ctrl;
 
-	pm_runtime_get_sync(chip->dev);
+	pm_runtime_get_sync(pwmchip_parent(chip));
 
 	base_unit_range = BIT(lpwm->info->base_unit_bits);
 
@@ -235,7 +235,7 @@ static int pwm_lpss_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 	state->polarity = PWM_POLARITY_NORMAL;
 	state->enabled = !!(ctrl & PWM_ENABLE);
 
-	pm_runtime_put(chip->dev);
+	pm_runtime_put(pwmchip_parent(chip));
 
 	return 0;
 }