pwm: core: Reuse fwnode_to_pwmchip() in ACPI case

In ACPI case we may use matching by fwnode as provided via
fwnode_to_pwmchip(). This makes device_to_pwmchip() not needed
anymore.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/core.c

@@ -827,28 +827,6 @@ struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np,
 }
 EXPORT_SYMBOL_GPL(of_pwm_get);
 
-#if IS_ENABLED(CONFIG_ACPI)
-static struct pwm_chip *device_to_pwmchip(struct device *dev)
-{
-	struct pwm_chip *chip;
-
-	mutex_lock(&pwm_lock);
-
-	list_for_each_entry(chip, &pwm_chips, list) {
-		struct acpi_device *adev = ACPI_COMPANION(chip->dev);
-
-		if ((chip->dev == dev) || (adev && &adev->dev == dev)) {
-			mutex_unlock(&pwm_lock);
-			return chip;
-		}
-	}
-
-	mutex_unlock(&pwm_lock);
-
-	return ERR_PTR(-EPROBE_DEFER);
-}
-#endif
-
 /**
  * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI
  * @fwnode: firmware node to get the "pwm" property from
@@ -869,9 +847,7 @@ static struct pwm_chip *device_to_pwmchip(struct device *dev)
 static struct pwm_device *acpi_pwm_get(struct fwnode_handle *fwnode)
 {
 	struct pwm_device *pwm = ERR_PTR(-ENODEV);
-#if IS_ENABLED(CONFIG_ACPI)
 	struct fwnode_reference_args args;
-	struct acpi_device *acpi;
 	struct pwm_chip *chip;
 	int ret;
 
@@ -881,14 +857,10 @@ static struct pwm_device *acpi_pwm_get(struct fwnode_handle *fwnode)
 	if (ret < 0)
 		return ERR_PTR(ret);
 
-	acpi = to_acpi_device_node(args.fwnode);
-	if (!acpi)
-		return ERR_PTR(-EINVAL);
-
 	if (args.nargs < 2)
 		return ERR_PTR(-EPROTO);
 
-	chip = device_to_pwmchip(&acpi->dev);
+	chip = fwnode_to_pwmchip(args.fwnode);
 	if (IS_ERR(chip))
 		return ERR_CAST(chip);
 
@@ -901,7 +873,6 @@ static struct pwm_device *acpi_pwm_get(struct fwnode_handle *fwnode)
 
 	if (args.nargs > 2 && args.args[2] & PWM_POLARITY_INVERTED)
 		pwm->args.polarity = PWM_POLARITY_INVERSED;
-#endif
 
 	return pwm;
 }