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-rmi.c b/drivers/hid/hid-rmi.c
index 2c14812..67cd059 100644
--- a/drivers/hid/hid-rmi.c
+++ b/drivers/hid/hid-rmi.c
@@ -1173,7 +1173,7 @@
 	return 0;
 }
 
-static void rmi_input_configured(struct hid_device *hdev, struct hid_input *hi)
+static int rmi_input_configured(struct hid_device *hdev, struct hid_input *hi)
 {
 	struct rmi_data *data = hid_get_drvdata(hdev);
 	struct input_dev *input = hi->input;
@@ -1185,10 +1185,10 @@
 	hid_dbg(hdev, "Opening low level driver\n");
 	ret = hid_hw_open(hdev);
 	if (ret)
-		return;
+		return ret;
 
 	if (!(data->device_flags & RMI_DEVICE))
-		return;
+		return 0;
 
 	/* Allow incoming hid reports */
 	hid_device_io_start(hdev);
@@ -1228,7 +1228,9 @@
 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 0x0f, 0, 0);
 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 0x0f, 0, 0);
 
-	input_mt_init_slots(input, data->max_fingers, INPUT_MT_POINTER);
+	ret = input_mt_init_slots(input, data->max_fingers, INPUT_MT_POINTER);
+	if (ret < 0)
+		goto exit;
 
 	if (data->button_count) {
 		__set_bit(EV_KEY, input->evbit);
@@ -1244,6 +1246,7 @@
 exit:
 	hid_device_io_stop(hdev);
 	hid_hw_close(hdev);
+	return ret;
 }
 
 static int rmi_input_mapping(struct hid_device *hdev,