Bluetooth: Introduce driver specific post init callback

Some drivers might have to restore certain settings after the init
procedure has been completed. This driver callback allows them to hook
into that stage. This callback is run just before the controller is
declared as powered up.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

include/net/bluetooth/hci_core.h

@@ -398,6 +398,7 @@ struct hci_dev {
 	int (*send)(struct hci_dev *hdev, struct sk_buff *skb);
 	void (*notify)(struct hci_dev *hdev, unsigned int evt);
 	void (*hw_error)(struct hci_dev *hdev, u8 code);
+	int (*post_init)(struct hci_dev *hdev);
 	int (*set_diag)(struct hci_dev *hdev, bool enable);
 	int (*set_bdaddr)(struct hci_dev *hdev, const bdaddr_t *bdaddr);
 };

net/bluetooth/hci_core.c

@@ -1503,8 +1503,11 @@ static int hci_dev_do_open(struct hci_dev *hdev)
 
 	if (!ret) {
 		if (!hci_dev_test_flag(hdev, HCI_UNCONFIGURED) &&
-		    !hci_dev_test_flag(hdev, HCI_USER_CHANNEL))
+		    !hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) {
 			ret = __hci_init(hdev);
+			if (!ret && hdev->post_init)
+				ret = hdev->post_init(hdev);
+		}
 	}
 
 	/* If the HCI Reset command is clearing all diagnostic settings,