HID: hid-sony.c: Use devm_ api to simplify sony_register_sensors()

[PATCH 2/5] HID: hid-sony.c: Use devm_ api to simplify sony_register_sensors()

Using devm_ calls, the resources of the Sony game devices's features are
tied to the main device handle, making it easier to handle errors and
teardown inside the device driver. Altogether, this reduces complexity
of the driver source.
Signed-off-by: Hanno Zulla <kontakt@hanno.de>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-sony.c

@@ -1417,7 +1417,7 @@ static int sony_register_sensors(struct sony_sc *sc)
 	int ret;
 	int range;
 
-	sc->sensor_dev = input_allocate_device();
+	sc->sensor_dev = devm_input_allocate_device(&sc->hdev->dev);
 	if (!sc->sensor_dev)
 		return -ENOMEM;
 
@@ -1434,11 +1434,9 @@ static int sony_register_sensors(struct sony_sc *sc)
 	 * DS4 compatible non-Sony devices with different names.
 	 */
 	name_sz = strlen(sc->hdev->name) + sizeof(SENSOR_SUFFIX);
-	name = kzalloc(name_sz, GFP_KERNEL);
-	if (!name) {
-		ret = -ENOMEM;
-		goto err;
-	}
+	name = devm_kzalloc(&sc->hdev->dev, name_sz, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
 	snprintf(name, name_sz, "%s" SENSOR_SUFFIX, sc->hdev->name);
 	sc->sensor_dev->name = name;
 
@@ -1480,33 +1478,11 @@ static int sony_register_sensors(struct sony_sc *sc)
 
 	ret = input_register_device(sc->sensor_dev);
 	if (ret < 0)
-		goto err;
-
-	return 0;
-
-err:
-	kfree(sc->sensor_dev->name);
-	sc->sensor_dev->name = NULL;
-
-	input_free_device(sc->sensor_dev);
-	sc->sensor_dev = NULL;
-
 		return ret;
-}
-
-static void sony_unregister_sensors(struct sony_sc *sc)
-{
-	if (!sc->sensor_dev)
-		return;
 
-	kfree(sc->sensor_dev->name);
-	sc->sensor_dev->name = NULL;
-
-	input_unregister_device(sc->sensor_dev);
-	sc->sensor_dev = NULL;
+	return 0;
 }
 
-
 /*
  * Sending HID_REQ_GET_REPORT changes the operation mode of the ps3 controller
  * to "operational".  Without this, the ps3 controller will not report any
@@ -2860,8 +2836,6 @@ static int sony_input_configured(struct hid_device *hdev,
 		sony_leds_remove(sc);
 	if (sc->quirks & SONY_BATTERY_SUPPORT)
 		sony_battery_remove(sc);
-	if (sc->sensor_dev)
-		sony_unregister_sensors(sc);
 	sony_cancel_work_sync(sc);
 	kfree(sc->output_report_dmabuf);
 	sony_remove_dev_list(sc);
@@ -2946,9 +2920,6 @@ static void sony_remove(struct hid_device *hdev)
 	if (sc->quirks & SONY_BATTERY_SUPPORT)
 		sony_battery_remove(sc);
 
-	if (sc->sensor_dev)
-		sony_unregister_sensors(sc);
-
 	if (sc->quirks & DUALSHOCK4_CONTROLLER_BT)
 		device_remove_file(&sc->hdev->dev, &dev_attr_bt_poll_interval);