HID: hid-input: allow input_configured callback return errors

When configuring input device via input_configured callback we may
encounter errors (for example input_mt_init_slots() may fail). Instead
of continuing with half-initialized input device let's allow driver
indicate failures.

Signed-off-by: Jaikumar Ganesh <jaikumarg@android.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Nikolai Kondrashov <Nikolai.Kondrashov@redhat.com>
Acked-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-magicmouse.c b/drivers/hid/hid-magicmouse.c
index 29a74c1..d6fa496 100644
--- a/drivers/hid/hid-magicmouse.c
+++ b/drivers/hid/hid-magicmouse.c
@@ -471,18 +471,22 @@
 	return 0;
 }
 
-static void magicmouse_input_configured(struct hid_device *hdev,
+static int magicmouse_input_configured(struct hid_device *hdev,
 		struct hid_input *hi)
 
 {
 	struct magicmouse_sc *msc = hid_get_drvdata(hdev);
+	int ret;
 
-	int ret = magicmouse_setup_input(msc->input, hdev);
+	ret = magicmouse_setup_input(msc->input, hdev);
 	if (ret) {
 		hid_err(hdev, "magicmouse setup input failed (%d)\n", ret);
 		/* clean msc->input to notify probe() of the failure */
 		msc->input = NULL;
+		return ret;
 	}
+
+	return 0;
 }