Bluetooth: Add a new mgmt_set_bredr command

This patch introduces a new mgmt command for enabling/disabling BR/EDR
functionality. This can be convenient when one wants to make a dual-mode
controller behave like a single-mode one. The command is only available
for dual-mode controllers and requires that LE is enabled before using
it. The BR/EDR setting can be enabled at any point, however disabling it
requires the controller to be powered off (otherwise a "rejected"
response will be sent).

Disabling the BR/EDR setting will automatically disable all other BR/EDR
related settings.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index d171c04b..4785ab0 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -297,6 +297,11 @@
 		goto done;
 	}
 
+	/* We need to ensure that we set this back on if someone changed
+	 * the scan mode through a raw HCI socket.
+	 */
+	set_bit(HCI_BREDR_ENABLED, &hdev->dev_flags);
+
 	old_pscan = test_and_clear_bit(HCI_PSCAN, &hdev->flags);
 	old_iscan = test_and_clear_bit(HCI_ISCAN, &hdev->flags);