pwm-backlight: Use devm_pwm_get() instead of pwm_get()

Managed versions of the pwm_get() and pwm_put() functions were recently
added to the PWM framework. They can be used to simplify cleanup in the
error paths and the device removal callback.

Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

drivers/video/backlight/pwm_bl.c

@@ -213,7 +213,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	pb->exit = data->exit;
 	pb->dev = &pdev->dev;
 
-	pb->pwm = pwm_get(&pdev->dev, NULL);
+	pb->pwm = devm_pwm_get(&pdev->dev, NULL);
 	if (IS_ERR(pb->pwm)) {
 		dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
 
@@ -246,7 +246,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	if (IS_ERR(bl)) {
 		dev_err(&pdev->dev, "failed to register backlight\n");
 		ret = PTR_ERR(bl);
-		goto err_bl;
+		goto err_alloc;
 	}
 
 	bl->props.brightness = data->dft_brightness;
@@ -255,8 +255,6 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, bl);
 	return 0;
 
-err_bl:
-	pwm_put(pb->pwm);
 err_alloc:
 	if (data->exit)
 		data->exit(&pdev->dev);
@@ -271,7 +269,6 @@ static int pwm_backlight_remove(struct platform_device *pdev)
 	backlight_device_unregister(bl);
 	pwm_config(pb->pwm, 0, pb->period);
 	pwm_disable(pb->pwm);
-	pwm_put(pb->pwm);
 	if (pb->exit)
 		pb->exit(&pdev->dev);
 	return 0;