HID: wiimote: Add wiimote device structure

Allocate wiimote device structure with all wiimote related data
when registering new wiimote devices.
Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-wiimote.c

@@ -17,6 +17,10 @@
 #define WIIMOTE_VERSION "0.1"
 #define WIIMOTE_NAME "Nintendo Wii Remote"
 
+struct wiimote_data {
+	struct hid_device *hdev;
+};
+
 static int wiimote_hid_event(struct hid_device *hdev, struct hid_report *report,
 							u8 *raw_data, int size)
 {
@@ -26,31 +30,64 @@ static int wiimote_hid_event(struct hid_device *hdev, struct hid_report *report,
 	return 0;
 }
 
+static struct wiimote_data *wiimote_create(struct hid_device *hdev)
+{
+	struct wiimote_data *wdata;
+
+	wdata = kzalloc(sizeof(*wdata), GFP_KERNEL);
+	if (!wdata)
+		return NULL;
+
+	wdata->hdev = hdev;
+	hid_set_drvdata(hdev, wdata);
+
+	return wdata;
+}
+
+static void wiimote_destroy(struct wiimote_data *wdata)
+{
+	kfree(wdata);
+}
+
 static int wiimote_hid_probe(struct hid_device *hdev,
 				const struct hid_device_id *id)
 {
+	struct wiimote_data *wdata;
 	int ret;
 
+	wdata = wiimote_create(hdev);
+	if (!wdata) {
+		hid_err(hdev, "Can't alloc device\n");
+		return -ENOMEM;
+	}
+
 	ret = hid_parse(hdev);
 	if (ret) {
 		hid_err(hdev, "HID parse failed\n");
-		return ret;
+		goto err;
 	}
 
 	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
 	if (ret) {
 		hid_err(hdev, "HW start failed\n");
-		return ret;
+		goto err;
 	}
 
 	hid_info(hdev, "New device registered\n");
 	return 0;
+
+err:
+	wiimote_destroy(wdata);
+	return ret;
 }
 
 static void wiimote_hid_remove(struct hid_device *hdev)
 {
+	struct wiimote_data *wdata = hid_get_drvdata(hdev);
+
 	hid_info(hdev, "Device removed\n");
 	hid_hw_stop(hdev);
+	wiimote_destroy(wdata);
 }
 
 static const struct hid_device_id wiimote_hid_devices[] = {