Bluetooth: Add LE connect support

Bluetooth V4.0 adds support for Low Energy (LE) connections.
Specification introduces new set of hci commands to control LE
connection. This patch adds logic to create, cancel and disconnect
LE connections.

Signed-off-by: Ville Tervo <ville.tervo@nokia.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

4 files changed, 164 insertions, 7 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 802d2505f138..e756f82a29e5 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -168,6 +168,8 @@ enum {
 #define SCO_LINK        0x00
 #define ACL_LINK        0x01
 #define ESCO_LINK       0x02
+/* Low Energy links do not have defined link type. Use invented one */
+#define LE_LINK         0x80
 
 /* LMP features */
 #define LMP_3SLOT       0x01
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6163bff6fa91..f434e96ce020 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -60,6 +60,7 @@ struct hci_conn_hash {
         spinlock_t       lock;
         unsigned int     acl_num;
         unsigned int     sco_num;
+        unsigned int     le_num;
 };
 
 struct bdaddr_list {
@@ -309,20 +310,36 @@ static inline void hci_conn_hash_add(struct hci_dev *hdev, struct hci_conn *c)
 {
         struct hci_conn_hash *h = &hdev->conn_hash;
         list_add(&c->list, &h->list);
-        if (c->type == ACL_LINK)
+        switch (c->type) {
+        case ACL_LINK:
                 h->acl_num++;
-        else
+                break;
+        case LE_LINK:
+                h->le_num++;
+                break;
+        case SCO_LINK:
+        case ESCO_LINK:
                 h->sco_num++;
+                break;
+        }
 }
 
 static inline void hci_conn_hash_del(struct hci_dev *hdev, struct hci_conn *c)
 {
         struct hci_conn_hash *h = &hdev->conn_hash;
         list_del(&c->list);
-        if (c->type == ACL_LINK)
+        switch (c->type) {
+        case ACL_LINK:
                 h->acl_num--;
-        else
+                break;
+        case LE_LINK:
+                h->le_num--;
+                break;
+        case SCO_LINK:
+        case ESCO_LINK:
                 h->sco_num--;
+                break;
+        }
 }
 
 static inline struct hci_conn *hci_conn_hash_lookup_handle(struct hci_dev *hdev,
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 42dc39f25b72..d0c470c18f9d 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -45,6 +45,32 @@
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
 
+static void hci_le_connect(struct hci_conn *conn)
+{
+        struct hci_dev *hdev = conn->hdev;
+        struct hci_cp_le_create_conn cp;
+
+        conn->state = BT_CONNECT;
+        conn->out = 1;
+
+        memset(&cp, 0, sizeof(cp));
+        cp.scan_interval = cpu_to_le16(0x0004);
+        cp.scan_window = cpu_to_le16(0x0004);
+        bacpy(&cp.peer_addr, &conn->dst);
+        cp.conn_interval_min = cpu_to_le16(0x0008);
+        cp.conn_interval_max = cpu_to_le16(0x0100);
+        cp.supervision_timeout = cpu_to_le16(0x0064);
+        cp.min_ce_len = cpu_to_le16(0x0001);
+        cp.max_ce_len = cpu_to_le16(0x0001);
+
+        hci_send_cmd(hdev, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
+}
+
+static void hci_le_connect_cancel(struct hci_conn *conn)
+{
+        hci_send_cmd(conn->hdev, HCI_OP_LE_CREATE_CONN_CANCEL, 0, NULL);
+}
+
 void hci_acl_connect(struct hci_conn *conn)
 {
         struct hci_dev *hdev = conn->hdev;
@@ -193,8 +219,12 @@ static void hci_conn_timeout(unsigned long arg)
         switch (conn->state) {
         case BT_CONNECT:
         case BT_CONNECT2:
-                if (conn->type == ACL_LINK && conn->out)
-                        hci_acl_connect_cancel(conn);
+                if (conn->out) {
+                        if (conn->type == ACL_LINK)
+                                hci_acl_connect_cancel(conn);
+                        else if (conn->type == LE_LINK)
+                                hci_le_connect_cancel(conn);
+                }
                 break;
         case BT_CONFIG:
         case BT_CONNECTED:
@@ -361,15 +391,30 @@ struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src)
 }
 EXPORT_SYMBOL(hci_get_route);
 
-/* Create SCO or ACL connection.
+/* Create SCO, ACL or LE connection.
  * Device _must_ be locked */
 struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8 sec_level, __u8 auth_type)
 {
         struct hci_conn *acl;
         struct hci_conn *sco;
+        struct hci_conn *le;
 
         BT_DBG("%s dst %s", hdev->name, batostr(dst));
 
+        if (type == LE_LINK) {
+                le = hci_conn_hash_lookup_ba(hdev, LE_LINK, dst);
+                if (!le)
+                        le = hci_conn_add(hdev, LE_LINK, dst);
+                if (!le)
+                        return NULL;
+                if (le->state == BT_OPEN)
+                        hci_le_connect(le);
+
+                hci_conn_hold(le);
+
+                return le;
+        }
+
         acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
         if (!acl) {
                 acl = hci_conn_add(hdev, ACL_LINK, dst);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index cee46cbe7aeb..47c6e9316ce8 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1107,6 +1107,43 @@ static void hci_cs_exit_sniff_mode(struct hci_dev *hdev, __u8 status)
         hci_dev_unlock(hdev);
 }
 
+static void hci_cs_le_create_conn(struct hci_dev *hdev, __u8 status)
+{
+        struct hci_cp_le_create_conn *cp;
+        struct hci_conn *conn;
+
+        BT_DBG("%s status 0x%x", hdev->name, status);
+
+        cp = hci_sent_cmd_data(hdev, HCI_OP_LE_CREATE_CONN);
+        if (!cp)
+                return;
+
+        hci_dev_lock(hdev);
+
+        conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, &cp->peer_addr);
+
+        BT_DBG("%s bdaddr %s conn %p", hdev->name, batostr(&cp->peer_addr),
+                conn);
+
+        if (status) {