pwm: Add a device-managed function to add PWM chips

This potentially simplifies low-level PWM drivers.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/core.c

@@ -335,6 +335,25 @@ int pwmchip_remove(struct pwm_chip *chip)
 }
 EXPORT_SYMBOL_GPL(pwmchip_remove);
 
+static void devm_pwmchip_remove(void *data)
+{
+	struct pwm_chip *chip = data;
+
+	pwmchip_remove(chip);
+}
+
+int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip)
+{
+	int ret;
+
+	ret = pwmchip_add(chip);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, devm_pwmchip_remove, chip);
+}
+EXPORT_SYMBOL_GPL(devm_pwmchip_add);
+
 /**
  * pwm_request() - request a PWM device
  * @pwm: global PWM device index

include/linux/pwm.h

@@ -405,6 +405,9 @@ void *pwm_get_chip_data(struct pwm_device *pwm);
 
 int pwmchip_add(struct pwm_chip *chip);
 int pwmchip_remove(struct pwm_chip *chip);
+
+int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip);
+
 struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
 					 unsigned int index,
 					 const char *label);