pwm: img: 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/bbea7e6e4c5412c6b0773faa9f165b6311cd53b6.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-img.c

@@ -98,7 +98,7 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	if (period_ns < imgchip->min_period_ns ||
 	    period_ns > imgchip->max_period_ns) {
-		dev_err(chip->dev, "configured period not in range\n");
+		dev_err(pwmchip_parent(chip), "configured period not in range\n");
 		return -ERANGE;
 	}
 
@@ -119,14 +119,14 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
 		timebase = DIV_ROUND_UP(mul, 512);
 	} else {
-		dev_err(chip->dev,
+		dev_err(pwmchip_parent(chip),
 			"failed to configure timebase steps/divider value\n");
 		return -EINVAL;
 	}
 
 	duty = DIV_ROUND_UP(timebase * duty_ns, period_ns);
 
-	ret = pm_runtime_resume_and_get(chip->dev);
+	ret = pm_runtime_resume_and_get(pwmchip_parent(chip));
 	if (ret < 0)
 		return ret;
 
@@ -140,8 +140,8 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	      (timebase << PWM_CH_CFG_TMBASE_SHIFT);
 	img_pwm_writel(imgchip, PWM_CH_CFG(pwm->hwpwm), val);
 
-	pm_runtime_mark_last_busy(chip->dev);
-	pm_runtime_put_autosuspend(chip->dev);
+	pm_runtime_mark_last_busy(pwmchip_parent(chip));
+	pm_runtime_put_autosuspend(pwmchip_parent(chip));
 
 	return 0;
 }
@@ -152,7 +152,7 @@ static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
 	int ret;
 
-	ret = pm_runtime_resume_and_get(chip->dev);
+	ret = pm_runtime_resume_and_get(pwmchip_parent(chip));
 	if (ret < 0)
 		return ret;
 
@@ -176,8 +176,8 @@ static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 	val &= ~BIT(pwm->hwpwm);
 	img_pwm_writel(imgchip, PWM_CTRL_CFG, val);
 
-	pm_runtime_mark_last_busy(chip->dev);
-	pm_runtime_put_autosuspend(chip->dev);
+	pm_runtime_mark_last_busy(pwmchip_parent(chip));
+	pm_runtime_put_autosuspend(pwmchip_parent(chip));
 }
 
 static int img_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,