Bluetooth: Create basic LE scan interface

Adds needed data structures.
Adds basic HCI interface to start/stop LE scan.

Change-Id: I69790b11d191078952ce05da386961c5c55a7172
Signed-off-by: Arkadiusz Lichwa <arkadiusz.lichwa@tieto.com>

include/bluetooth/bluetooth.h

@@ -87,5 +87,7 @@ struct bt_eir {
 
 int bt_start_advertising(uint8_t type, const struct bt_eir *ad,
 			 const struct bt_eir *sd);
+int bt_start_scanning(uint8_t scan_type, uint8_t scan_filter);
+int bt_stop_scanning();
 
 #endif /* __BT_BLUETOOTH_H */

include/bluetooth/hci.h

@@ -202,6 +202,30 @@ struct bt_hci_cp_le_set_adv_enable {
 	uint8_t  enable;
 } PACK_STRUCT;
 
+/* Scan types */
+#define BT_HCI_OP_LE_SET_SCAN_PARAMS		BT_OP(BT_OGF_LE, 0x000b)
+#define BT_LE_SCAN_PASSIVE			0x00
+#define BT_LE_SCAN_ACTIVE			0x01
+
+struct bt_hci_cp_le_set_scan_params {
+	uint8_t  scan_type;
+	uint16_t interval;
+	uint16_t window;
+	uint8_t  addr_type;
+	uint8_t  filter_policy;
+} PACK_STRUCT;
+
+#define BT_HCI_OP_LE_SET_SCAN_ENABLE		BT_OP(BT_OGF_LE, 0x000c)
+#define BT_LE_SCAN_DISABLE			0x00
+#define BT_LE_SCAN_ENABLE			0x01
+#define BT_LE_SCAN_FILTER_DUP_DISABLE		0x00
+#define BT_LE_SCAN_FILTER_DUP_ENABLE		0x01
+
+struct bt_hci_cp_le_set_scan_enable {
+	uint8_t  enable;
+	uint8_t  filter_dup;
+} PACK_STRUCT;
+
 #define BT_HCI_OP_LE_ENCRYPT			BT_OP(BT_OGF_LE, 0x0017)
 struct bt_hci_cp_le_encrypt {
 	uint8_t  key[16];

net/bluetooth/hci_core.c

@@ -828,3 +828,92 @@ send_set_param:
 
 	return bt_hci_cmd_send_sync(BT_HCI_OP_LE_SET_ADV_ENABLE, buf, NULL);
 }
+
+int bt_start_scanning(uint8_t scan_type, uint8_t scan_filter)
+{
+	struct bt_buf *buf, *rsp;
+	struct bt_hci_cp_le_set_scan_params *set_param;
+	struct bt_hci_cp_le_set_scan_enable *scan_enable;
+	int err;
+
+	if (dev.scan_enable == BT_LE_SCAN_ENABLE) {
+		return -EALREADY;
+	}
+
+	buf = bt_hci_cmd_create(BT_HCI_OP_LE_SET_SCAN_PARAMS, sizeof(*set_param));
+	if (!buf) {
+		return -ENOBUFS;
+	}
+
+	set_param = (void *)bt_buf_add(buf, sizeof(*set_param));
+	memset(set_param, 0, sizeof(*set_param));
+	set_param->scan_type = scan_type;
+
+	/* for the rest parameters apply default values according to
+	 *  spec 4.2, vol2, part E, 7.8.10
+	 */
+	set_param->interval = sys_cpu_to_le16(0x0010);
+	set_param->window = sys_cpu_to_le16(0x0010);
+	set_param->filter_policy = 0x00;
+	set_param->addr_type = 0x00;
+
+	bt_hci_cmd_send(BT_HCI_OP_LE_SET_SCAN_PARAMS, buf);
+	buf = bt_hci_cmd_create(BT_HCI_OP_LE_SET_SCAN_ENABLE, sizeof(*scan_enable));
+	if (!buf) {
+		return -ENOBUFS;
+	}
+
+	scan_enable = (void *)bt_buf_add(buf, sizeof(*scan_enable));
+	memset(scan_enable, 0, sizeof(*scan_enable));
+	scan_enable->filter_dup = scan_filter;
+	scan_enable->enable = BT_LE_SCAN_ENABLE;
+
+	err = bt_hci_cmd_send_sync(BT_HCI_OP_LE_SET_SCAN_ENABLE, buf, &rsp);
+	if (err) {
+		return err;
+	}
+
+	/* Update scan state in case of success (0) status */
+	if (!rsp->data[0]) {
+		dev.scan_enable = BT_LE_SCAN_ENABLE;
+	}
+
+	bt_buf_put(rsp);
+
+	return 0;
+}
+
+int bt_stop_scanning()
+{
+	struct bt_buf *buf, *rsp;
+	struct bt_hci_cp_le_set_scan_enable *scan_enable;
+	int err;
+
+	if (dev.scan_enable == BT_LE_SCAN_DISABLE) {
+		return -EALREADY;
+	}
+
+	buf = bt_hci_cmd_create(BT_HCI_OP_LE_SET_SCAN_ENABLE, sizeof(*scan_enable));
+	if (!buf) {
+		return -ENOBUFS;
+	}
+
+	scan_enable = (void *)bt_buf_add(buf, sizeof(*scan_enable));
+	memset(scan_enable, 0x0, sizeof(*scan_enable));
+	scan_enable->filter_dup = 0x00;
+	scan_enable->enable = BT_LE_SCAN_DISABLE;
+
+	err =  bt_hci_cmd_send_sync(BT_HCI_OP_LE_SET_SCAN_ENABLE, buf, &rsp);
+	if (err) {
+		return err;
+	}
+
+	/* Update scan state in case of success (0) status */
+	if (!rsp->data[0]) {
+		dev.scan_enable = BT_LE_SCAN_DISABLE;
+	}
+
+	bt_buf_put(rsp);
+
+	return 0;
+}

net/bluetooth/hci_core.h

@@ -53,6 +53,9 @@ struct bt_dev {
 	/* Advertising state */
 	uint8_t                 adv_enable;
 
+	/* Scanning state */
+	uint8_t			scan_enable;
+
 	/* Controller buffer information */
 	uint8_t			le_pkts;
 	uint16_t		le_mtu;