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>

3 files changed, 127 insertions, 0 deletions

diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 421d7633a91f..7347df800a2e 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -354,6 +354,8 @@ struct mgmt_cp_set_device_id {
 
 #define MGMT_OP_SET_ADVERTISING         0x0029
 
+#define MGMT_OP_SET_BREDR               0x002A
+
 #define MGMT_EV_CMD_COMPLETE            0x0001
 struct mgmt_ev_cmd_complete {
         __le16  opcode;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index d171c04bddbd..4785ab0795f5 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -297,6 +297,11 @@ static void hci_cc_write_scan_enable(struct hci_dev *hdev, struct sk_buff *skb)
                 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);
 
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index e1c41b0b7a75..dcce0cf1d7cc 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -75,6 +75,7 @@ static const u16 mgmt_commands[] = {
         MGMT_OP_UNBLOCK_DEVICE,
         MGMT_OP_SET_DEVICE_ID,
         MGMT_OP_SET_ADVERTISING,
+        MGMT_OP_SET_BREDR,
 };
 
 static const u16 mgmt_events[] = {
@@ -3337,6 +3338,121 @@ unlock:
         return err;
 }
 
+static void set_bredr_complete(struct hci_dev *hdev, u8 status)
+{
+        struct pending_cmd *cmd;
+
+        BT_DBG("status 0x%02x", status);
+
+        hci_dev_lock(hdev);
+
+        cmd = mgmt_pending_find(MGMT_OP_SET_BREDR, hdev);
+        if (!cmd)
+                goto unlock;
+
+        if (status) {
+                u8 mgmt_err = mgmt_status(status);
+
+                /* We need to restore the flag if related HCI commands
+                 * failed.
+                 */
+                clear_bit(HCI_BREDR_ENABLED, &hdev->dev_flags);
+
+                cmd_status(cmd->sk, cmd->index, cmd->opcode, mgmt_err);
+        } else {
+                send_settings_rsp(cmd->sk, MGMT_OP_SET_BREDR, hdev);
+                new_settings(hdev, cmd->sk);
+        }
+
+        mgmt_pending_remove(cmd);
+
+unlock:
+        hci_dev_unlock(hdev);
+}
+
+static int set_bredr(struct sock *sk, struct hci_dev *hdev, void *data, u16 len)
+{
+        struct mgmt_mode *cp = data;
+        struct pending_cmd *cmd;
+        struct hci_request req;
+        int err;
+
+        BT_DBG("request for %s", hdev->name);
+
+        if (!lmp_bredr_capable(hdev) || !lmp_le_capable(hdev))
+                return cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                  MGMT_STATUS_NOT_SUPPORTED);
+
+        if (!test_bit(HCI_LE_ENABLED, &hdev->dev_flags))
+                return cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                  MGMT_STATUS_REJECTED);
+
+        if (cp->val != 0x00 && cp->val != 0x01)
+                return cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                  MGMT_STATUS_INVALID_PARAMS);
+
+        hci_dev_lock(hdev);
+
+        if (cp->val == test_bit(HCI_BREDR_ENABLED, &hdev->dev_flags)) {
+                err = send_settings_rsp(sk, MGMT_OP_SET_BREDR, hdev);
+                goto unlock;
+        }
+
+        if (!hdev_is_powered(hdev)) {
+                if (!cp->val) {
+                        clear_bit(HCI_CONNECTABLE, &hdev->dev_flags);
+                        clear_bit(HCI_DISCOVERABLE, &hdev->dev_flags);
+                        clear_bit(HCI_SSP_ENABLED, &hdev->dev_flags);
+                        clear_bit(HCI_LINK_SECURITY, &hdev->dev_flags);
+                        clear_bit(HCI_FAST_CONNECTABLE, &hdev->dev_flags);
+                        clear_bit(HCI_HS_ENABLED, &hdev->dev_flags);
+                }
+
+                change_bit(HCI_BREDR_ENABLED, &hdev->dev_flags);
+
+                err = send_settings_rsp(sk, MGMT_OP_SET_BREDR, hdev);
+                if (err < 0)
+                        goto unlock;
+
+                err = new_settings(hdev, sk);
+                goto unlock;
+        }
+
+        /* Reject disabling when powered on */
+        if (!cp->val) {
+                err = cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                 MGMT_STATUS_REJECTED);
+                goto unlock;
+        }
+
+        if (mgmt_pending_find(MGMT_OP_SET_BREDR, hdev)) {
+                err = cmd_status(sk, hdev->id, MGMT_OP_SET_BREDR,
+                                 MGMT_STATUS_BUSY);
+                goto unlock;
+        }
+
+        cmd = mgmt_pending_add(sk, MGMT_OP_SET_BREDR, hdev, data, len);
+        if (!cmd) {
+                err = -ENOMEM;
+                goto unlock;
+        }
+
+        /* We need to flip the bit already here so that hci_update_ad
+         * generates the correct flags.
+         */
+        set_bit(HCI_BREDR_ENABLED, &hdev->dev_flags);
+
+        hci_req_init(&req, hdev);
+        hci_update_ad(&req);
+        err = hci_req_run(&req, set_bredr_complete);
+        if (err < 0)
+                mgmt_pending_remove(cmd);
+
+unlock:
+        hci_dev_unlock(hdev);
+        return err;
+}
+
 static bool ltk_is_valid(struct mgmt_ltk_info *key)
 {
         if (key->authenticated != 0x00 && key->authenticated != 0x01)
@@ -3452,6 +3568,7 @@ static const struct mgmt_handler {
         { unblock_device,         false, MGMT_UNBLOCK_DEVICE_SIZE },
         { set_device_id,          false, MGMT_SET_DEVICE_ID_SIZE },
         { set_advertising,        false, MGMT_SETTING_SIZE },
+        { set_bredr,              false, MGMT_SETTING_SIZE },
 };
 
 
@@ -3633,6 +3750,9 @@ static int powered_update_hci(struct hci_dev *hdev)
                     cp.simul != lmp_host_le_br_capable(hdev))
                         hci_req_add(&req, HCI_OP_WRITE_LE_HOST_SUPPORTED,
                                     sizeof(cp), &cp);
+
+                /* In case BR/EDR was toggled during the AUTO_OFF phase */
+                hci_update_ad(&req);
         }
 
         if (test_bit(HCI_LE_PERIPHERAL, &hdev->dev_flags)) {