Bluetooth: btrtl: HCI reset on close for Realtek BT chip

Realtek RTL8822BE BT chip on ASUS X420FA cannot be turned on correctly
after on-off several times. Bluetooth daemon sets BT mode failed when
this issue happens. Scanning must be active while turning off for this
bug to be hit.

bluetoothd[1576]: Failed to set mode: Failed (0x03)

If BT is turned off, then turned on again, it works correctly again.

According to the vendor driver, the HCI_QUIRK_RESET_ON_CLOSE flag is set
during probing. So, this patch makes Realtek's BT reset on close to fix
this issue.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=203429
Signed-off-by: Jian-Hong Pan <jian-hong@endlessm.com>
Reviewed-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/drivers/bluetooth/btrtl.h b/drivers/bluetooth/btrtl.h
index f167614..10ad40c 100644
--- a/drivers/bluetooth/btrtl.h
+++ b/drivers/bluetooth/btrtl.h
@@ -55,6 +55,7 @@ void btrtl_free(struct btrtl_device_info *btrtl_dev);
 int btrtl_download_firmware(struct hci_dev *hdev,
 			    struct btrtl_device_info *btrtl_dev);
 int btrtl_setup_realtek(struct hci_dev *hdev);
+int btrtl_shutdown_realtek(struct hci_dev *hdev);
 int btrtl_get_uart_settings(struct hci_dev *hdev,
 			    struct btrtl_device_info *btrtl_dev,
 			    unsigned int *controller_baudrate,
@@ -83,6 +84,11 @@ static inline int btrtl_setup_realtek(struct hci_dev *hdev)
 	return -EOPNOTSUPP;
 }
 
+static inline int btrtl_shutdown_realtek(struct hci_dev *hdev)
+{
+	return -EOPNOTSUPP;
+}
+
 static inline int btrtl_get_uart_settings(struct hci_dev *hdev,
 					  struct btrtl_device_info *btrtl_dev,
 					  unsigned int *controller_baudrate,