HID: trivial devm conversion for special hid drivers

It is safe to use devres allocation within the hid subsystem:
- the devres release is called _after_ the call to .remove(), meaning
  that no freed pointers will exists while removing the device
- if a .probe() fails, devres releases all the allocated ressources
  before going to the next driver: there will not be ghost ressources
  attached to a hid device if several drivers are probed.

Given that, we can clean up a little some of the HID drivers. These ones
are trivial:
- there is only one kzalloc in the driver
- the .remove() callback contains only one kfree on top of hid_hw_stop()
- the error path in the probe is easy enough to be manually checked

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 4 insertions, 17 deletions

diff --git a/drivers/hid/hid-a4tech.c b/drivers/hid/hid-a4tech.c
index 7c5507e94820..9428ea7cdf8a 100644
--- a/drivers/hid/hid-a4tech.c
+++ b/drivers/hid/hid-a4tech.c
@@ -90,11 +90,10 @@ static int a4_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	struct a4tech_sc *a4;
 	int ret;
 
-	a4 = kzalloc(sizeof(*a4), GFP_KERNEL);
+	a4 = devm_kzalloc(&hdev->dev, sizeof(*a4), GFP_KERNEL);
 	if (a4 == NULL) {
 		hid_err(hdev, "can't alloc device descriptor\n");
-		ret = -ENOMEM;
-		goto err_free;
+		return -ENOMEM;
 	}
 
 	a4->quirks = id->driver_data;
@@ -104,27 +103,16 @@ static int a4_probe(struct hid_device *hdev, const struct hid_device_id *id)
 	ret = hid_parse(hdev);
 	if (ret) {
 		hid_err(hdev, "parse failed\n");
-		goto err_free;
+		return ret;
 	}
 
 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 	if (ret) {
 		hid_err(hdev, "hw start failed\n");
-		goto err_free;
+		return ret;
 	}
 
 	return 0;
-err_free:
-	kfree(a4);
-	return ret;
-}
-
-static void a4_remove(struct hid_device *hdev)
-{
-	struct a4tech_sc *a4 = hid_get_drvdata(hdev);
-
-	hid_hw_stop(hdev);
-	kfree(a4);
 }
 
 static const struct hid_device_id a4_devices[] = {
@@ -144,7 +132,6 @@ static struct hid_driver a4_driver = {
 	.input_mapped = a4_input_mapped,
 	.event = a4_event,
 	.probe = a4_probe,
-	.remove = a4_remove,
 };
 module_hid_driver(a4_driver);