Bluetooth: Interleaved discovery support

This patch adds interleaved discovery support to MGMT Start
Discovery command.

In case interleaved discovery is not supported (not a dual mode
device), we perform BR/EDR or LE-only discovery according to the
device capabilities.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

3 files changed, 57 insertions, 5 deletions

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 942de7764278..2aafeb3a8793 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -716,6 +716,7 @@ void hci_conn_del_sysfs(struct hci_conn *conn);
 #define lmp_ssp_capable(dev)       ((dev)->features[6] & LMP_SIMPLE_PAIR)
 #define lmp_no_flush_capable(dev)  ((dev)->features[6] & LMP_NO_FLUSH)
 #define lmp_le_capable(dev)        ((dev)->features[4] & LMP_LE)
+#define lmp_bredr_capable(dev)     (!((dev)->features[4] & LMP_NO_BREDR))
 
 /* ----- Extended LMP capabilities ----- */
 #define lmp_host_le_capable(dev)   ((dev)->host_features[0] & LMP_HOST_LE)
@@ -1019,6 +1020,7 @@ int mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 int mgmt_start_discovery_failed(struct hci_dev *hdev, u8 status);
 int mgmt_stop_discovery_failed(struct hci_dev *hdev, u8 status);
 int mgmt_discovering(struct hci_dev *hdev, u8 discovering);
+int mgmt_interleaved_discovery(struct hci_dev *hdev);
 int mgmt_device_blocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type);
 int mgmt_device_unblocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type);
 
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 9aea7b898821..04fb1f02dfcc 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1090,11 +1090,16 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
 
                 clear_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
-                hci_dev_lock(hdev);
-                hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
-                hci_dev_unlock(hdev);
-
                 schedule_delayed_work(&hdev->adv_work, ADV_CLEAR_TIMEOUT);
+
+                if (hdev->discovery.type == DISCOV_TYPE_INTERLEAVED) {
+                        mgmt_interleaved_discovery(hdev);
+                } else {
+                        hci_dev_lock(hdev);
+                        hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
+                        hci_dev_unlock(hdev);
+                }
+
                 break;
 
         default:
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a9cd38dc2cab..89754bbcd02b 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -108,8 +108,10 @@ static const u16 mgmt_events[] = {
 #define LE_SCAN_WIN                     0x12
 #define LE_SCAN_INT                     0x12
 #define LE_SCAN_TIMEOUT_LE_ONLY         10240   /* TGAP(gen_disc_scan_min) */
+#define LE_SCAN_TIMEOUT_BREDR_LE        5120    /* TGAP(100)/2 */
 
 #define INQUIRY_LEN_BREDR               0x08    /* TGAP(100) */
+#define INQUIRY_LEN_BREDR_LE            0x04    /* TGAP(100)/2 */
 
 #define SERVICE_CACHE_TIMEOUT (5 * 1000)
 
@@ -2153,6 +2155,46 @@ static int remove_remote_oob_data(struct sock *sk, u16 index,
         return err;
 }
 
+static int discovery(struct hci_dev *hdev)
+{
+        int err;
+
+        if (lmp_host_le_capable(hdev)) {
+                if (lmp_bredr_capable(hdev)) {
+                        err = hci_le_scan(hdev, LE_SCAN_TYPE,
+                                                LE_SCAN_INT, LE_SCAN_WIN,
+                                                LE_SCAN_TIMEOUT_BREDR_LE);
+                } else {
+                        hdev->discovery.type = DISCOV_TYPE_LE;
+                        err = hci_le_scan(hdev, LE_SCAN_TYPE,
+                                                LE_SCAN_INT, LE_SCAN_WIN,
+                                                LE_SCAN_TIMEOUT_LE_ONLY);
+                }
+        } else {
+                hdev->discovery.type = DISCOV_TYPE_BREDR;
+                err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR);
+        }
+
+        return err;
+}
+
+int mgmt_interleaved_discovery(struct hci_dev *hdev)
+{
+        int err;
+
+        BT_DBG("%s", hdev->name);
+
+        hci_dev_lock(hdev);
+
+        err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR_LE);
+        if (err < 0)
+                hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
+
+        hci_dev_unlock(hdev);
+
+        return err;
+}
+
 static int start_discovery(struct sock *sk, u16 index,
                                                 void *data, u16 len)
 {
@@ -2196,7 +2238,6 @@ static int start_discovery(struct sock *sk, u16 index,
 
         switch (hdev->discovery.type) {
         case DISCOV_TYPE_BREDR:
-        case DISCOV_TYPE_INTERLEAVED:
                 err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR);
                 break;
 
@@ -2205,6 +2246,10 @@ static int start_discovery(struct sock *sk, u16 index,
                                         LE_SCAN_WIN, LE_SCAN_TIMEOUT_LE_ONLY);
                 break;
 
+        case DISCOV_TYPE_INTERLEAVED:
+                err = discovery(hdev);
+                break;
+
         default:
                 err = -EINVAL;
         }