Bluetooth: Add hci_do_le_scan()

This patch adds to hci_core the hci_do_le_scan function which
should be used to scan LE devices.

In order to enable LE scan, hci_do_le_scan() sends commands (Set
LE Scan Parameters and Set LE Scan Enable) to the controller and
waits for its results. If commands were executed successfully a
delayed work is scheduled to disable the ongoing scanning after
some amount of time. This function blocks.

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, 92 insertions, 3 deletions

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index bf2ef5667887..3e70872bffea 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -122,6 +122,12 @@ struct adv_entry {
         u8 bdaddr_type;
 };
 
+struct le_scan_params {
+        u8 type;
+        u16 interval;
+        u16 window;
+};
+
 #define NUM_REASSEMBLY 4
 struct hci_dev {
         struct list_head list;
@@ -261,6 +267,8 @@ struct hci_dev {
 
         unsigned long           dev_flags;
 
+        struct delayed_work     le_scan_disable;
+
         int (*open)(struct hci_dev *hdev);
         int (*close)(struct hci_dev *hdev);
         int (*flush)(struct hci_dev *hdev);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 1175f27bd445..ae86cdd80ac0 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -759,6 +759,8 @@ static int hci_dev_do_close(struct hci_dev *hdev)
         if (test_and_clear_bit(HCI_SERVICE_CACHE, &hdev->dev_flags))
                 cancel_delayed_work(&hdev->service_cache);
 
+        cancel_delayed_work_sync(&hdev->le_scan_disable);
+
         hci_dev_lock(hdev);
         inquiry_cache_flush(hdev);
         hci_conn_hash_flush(hdev);
@@ -1596,6 +1598,76 @@ int hci_add_adv_entry(struct hci_dev *hdev,
         return 0;
 }
 
+static void le_scan_param_req(struct hci_dev *hdev, unsigned long opt)
+{
+        struct le_scan_params *param =  (struct le_scan_params *) opt;
+        struct hci_cp_le_set_scan_param cp;
+
+        memset(&cp, 0, sizeof(cp));
+        cp.type = param->type;
+        cp.interval = cpu_to_le16(param->interval);
+        cp.window = cpu_to_le16(param->window);
+
+        hci_send_cmd(hdev, HCI_OP_LE_SET_SCAN_PARAM, sizeof(cp), &cp);
+}
+
+static void le_scan_enable_req(struct hci_dev *hdev, unsigned long opt)
+{
+        struct hci_cp_le_set_scan_enable cp;
+
+        memset(&cp, 0, sizeof(cp));
+        cp.enable = 1;
+
+        hci_send_cmd(hdev, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(cp), &cp);
+}
+
+static int hci_do_le_scan(struct hci_dev *hdev, u8 type, u16 interval,
+                                                u16 window, int timeout)
+{
+        long timeo = msecs_to_jiffies(3000);
+        struct le_scan_params param;
+        int err;
+
+        BT_DBG("%s", hdev->name);
+
+        if (test_bit(HCI_LE_SCAN, &hdev->dev_flags))
+                return -EINPROGRESS;
+
+        param.type = type;
+        param.interval = interval;
+        param.window = window;
+
+        hci_req_lock(hdev);
+
+        err = __hci_request(hdev, le_scan_param_req, (unsigned long) &param,
+                                                                        timeo);
+        if (!err)
+                err = __hci_request(hdev, le_scan_enable_req, 0, timeo);
+
+        hci_req_unlock(hdev);
+
+        if (err < 0)
+                return err;
+
+        schedule_delayed_work(&hdev->le_scan_disable,
+                                                msecs_to_jiffies(timeout));
+
+        return 0;
+}
+
+static void le_scan_disable_work(struct work_struct *work)
+{
+        struct hci_dev *hdev = container_of(work, struct hci_dev,
+                                                le_scan_disable.work);
+        struct hci_cp_le_set_scan_enable cp;
+
+        BT_DBG("%s", hdev->name);
+
+        memset(&cp, 0, sizeof(cp));
+
+        hci_send_cmd(hdev, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(cp), &cp);
+}
+
 /* Register HCI device */
 int hci_register_dev(struct hci_dev *hdev)
 {
@@ -1682,6 +1754,8 @@ int hci_register_dev(struct hci_dev *hdev)
 
         atomic_set(&hdev->promisc, 0);
 
+        INIT_DELAYED_WORK(&hdev->le_scan_disable, le_scan_disable_work);
+
         write_unlock(&hci_dev_list_lock);
 
         hdev->workqueue = alloc_workqueue(hdev->name, WQ_HIGHPRI | WQ_UNBOUND |
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 8971c18205c0..97152d9d7116 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1031,6 +1031,8 @@ static void hci_cc_le_set_scan_param(struct hci_dev *hdev, struct sk_buff *skb)
         __u8 status = *((__u8 *) skb->data);
 
         BT_DBG("%s status 0x%x", hdev->name, status);
+
+        hci_req_complete(hdev, HCI_OP_LE_SET_SCAN_PARAM, status);
 }
 
 static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
@@ -1041,15 +1043,17 @@ 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;
 
         switch (cp->enable) {
         case LE_SCANNING_ENABLED:
+                hci_req_complete(hdev, HCI_OP_LE_SET_SCAN_ENABLE, status);
+
+                if (status)
+                        return;
+
                 set_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
                 cancel_delayed_work_sync(&hdev->adv_work);
@@ -1061,6 +1065,9 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
                 break;
 
         case LE_SCANNING_DISABLED:
+                if (status)
+                        return;
+
                 clear_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
                 hci_dev_lock(hdev);