[PATCH 6/6] Bluetooth: Support LE-Only discovery procedure

[Andre Guedes <andre.guedes@openbossa.org>]

This patch adds support for LE-Only discovery procedure through
management interface.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
---
 include/net/bluetooth/hci.h      |    1 +
 include/net/bluetooth/hci_core.h |    1 +
 net/bluetooth/hci_event.c        |   25 ++++++++++++++++++++++---
 net/bluetooth/mgmt.c             |   25 +++++++++++++++++++++++--
 4 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index bd3cecd..ca09998 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -210,6 +210,7 @@ enum {
 
 #define LMP_EV4		0x01
 #define LMP_EV5		0x02
+#define LMP_NO_BREDR	0x20
 #define LMP_LE		0x40
 
 #define LMP_SNIFF_SUBR	0x02
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 9da5b69..55b78ec 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -678,6 +678,7 @@ 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)->extfeatures[0] & LMP_HOST_LE)
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index dcbbffe..037c7c0 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -954,24 +954,43 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
 
 	BT_DBG("%s status 0x%x", hdev->name, status);
 
-	if (status)
-		return;
-
 	cp = hci_sent_cmd_data(hdev, HCI_OP_LE_SET_SCAN_ENABLE);
 	if (!cp)
 		return;
 
 	if (cp->enable == 0x01) {
+		if (status) {
+			hci_dev_lock(hdev);
+			mgmt_start_discovery_failed(hdev, status);
+			hci_dev_unlock(hdev);
+			return;
+		}
+
 		set_bit(HCI_LE_SCAN, &hdev->hci_flags);
 
 		del_timer(&hdev->adv_timer);
 
 		hci_dev_lock(hdev);
+
+		mgmt_discovering(hdev, 1);
+
 		hci_adv_entries_clear(hdev);
+
 		hci_dev_unlock(hdev);
 	} else if (cp->enable == 0x00) {
+		if (status) {
+			hci_dev_lock(hdev);
+			mgmt_stop_discovery_failed(hdev, status);
+			hci_dev_unlock(hdev);
+			return;
+		}
+
 		clear_bit(HCI_LE_SCAN, &hdev->hci_flags);
 
+		hci_dev_lock(hdev);
+		mgmt_discovering(hdev, 0);
+		hci_dev_unlock(hdev);
+
 		mod_timer(&hdev->adv_timer, jiffies + ADV_CLEAR_TIMEOUT);
 	}
 }
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index b63a7d0..6ca6e5d 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -32,7 +32,16 @@
 #define MGMT_VERSION	0
 #define MGMT_REVISION	1
 
-#define INQUIRY_LEN_BREDR 0x08 /* TGAP(100) */
+/*
+ * These LE scan and inquiry parameters were chosen according to LE General
+ * Discovery Procedure specification.
+ */
+#define LE_SCAN_TYPE 0x01
+#define LE_SCAN_WIN 0x12
+#define LE_SCAN_INT 0x12
+#define LE_SCAN_TIMEOUT_LE_ONLY 10240		/* TGAP(gen_disc_scan_min) */
+
+#define INQUIRY_LEN_BREDR 0x08			/* TGAP(100) */
 
 struct pending_cmd {
 	struct list_head list;
@@ -1669,7 +1678,16 @@ static int start_discovery(struct sock *sk, u16 index)
 		goto failed;
 	}
 
-	err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR);
+	if (lmp_host_le_capable(hdev)) {
+		if (lmp_bredr_capable(hdev))
+			err = -ENOSYS;
+		else
+			err = hci_do_le_scan(hdev, LE_SCAN_TYPE, LE_SCAN_INT,
+					LE_SCAN_WIN, LE_SCAN_TIMEOUT_LE_ONLY);
+	} else {
+		err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR);
+	}
+
 	if (err < 0)
 		mgmt_pending_remove(cmd);
 
@@ -1701,6 +1719,9 @@ static int stop_discovery(struct sock *sk, u16 index)
 	}
 
 	err = hci_cancel_inquiry(hdev);
+	if (err == -EPERM)
+		err = hci_cancel_le_scan(hdev);
+
 	if (err < 0)
 		mgmt_pending_remove(cmd);
 
-- 
1.7.7.1