[PATCH v2] gpio: gpiolib: fix refcount imbalance in gpiochip_setup_dev()

[Joe Hattori <joe@xxxxxxxxxxxxxxxxxxxxx>]

The refcount incremented by the device_initialize() call in
gpiochip_setup_dev() is not decremented in the error path. Fix it by
calling gpio_device_put(). Consequently, the gpio_device_put() call in
gpiochip_add_data_with_key() is not needed, therefore remove it.

Fixes: aab5c6f20023 ("gpio: set device type for GPIO chips")
Signed-off-by: Joe Hattori <joe@xxxxxxxxxxxxxxxxxxxxx>
---
Changes in v2:
- Use gpio_device_put() instead of put_device().
- Remove the gpio_device_put() call in gpiochip_add_data_with_key().
---
 drivers/gpio/gpiolib.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 679ed764cb14..b3a1a6b8fdff 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -800,7 +800,7 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
 
 	ret = gcdev_register(gdev, gpio_devt);
 	if (ret)
-		return ret;
+		goto err_put_device;
 
 	ret = gpiochip_sysfs_register(gdev);
 	if (ret)
@@ -813,6 +813,8 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
 
 err_remove_device:
 	gcdev_unregister(gdev);
+err_put_device:
+	gpio_device_put(gdev);
 	return ret;
 }
 
@@ -1124,11 +1126,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	scoped_guard(mutex, &gpio_devices_lock)
 		list_del_rcu(&gdev->list);
 	synchronize_srcu(&gpio_devices_srcu);
-	if (gdev->dev.release) {
-		/* release() has been registered by gpiochip_setup_dev() */
-		gpio_device_put(gdev);
-		goto err_print_message;
-	}
 err_free_label:
 	kfree_const(gdev->label);
 err_free_descs:
@@ -1139,7 +1136,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	ida_free(&gpio_ida, gdev->id);
 err_free_gdev:
 	kfree(gdev);
-err_print_message:
 	/* failures here can mean systems won't boot... */
 	if (ret != -EPROBE_DEFER) {
 		pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
-- 
2.34.1