SIM: Add support Linux HCI Socket as BLE adaptor

arch/sim/Kconfig

@@ -475,4 +475,14 @@ config SIM_QSPIFLASH_PAGESIZE
 		"wrap" causing the initial data sent to be overwritten.
 		This is consistent with standard SPI FLASH operation.
 
+config SIM_HCISOCKET
+	bool "Attach Host Bluetooth"
+	default false
+	depends on (WIRELESS_BLUETOOTH && HOST_LINUX)
+	---help---
+		Attached the local bluetooth device to the simulation
+		target via HCI_CHANNEL_USER. This gives NuttX full
+		control of the device, but is abstracted from the
+		physical interface which is still handled by Linux.
+
 endif # ARCH_SIM

arch/sim/src/Makefile

@@ -196,6 +196,11 @@ else ifeq ($(CONFIG_SIM_NETDEV_VPNKIT),y)
   HOSTSRCS += protocol.c negotiate.c
 endif
 
+ifeq ($(CONFIG_SIM_HCISOCKET),y)
+  HOSTSRCS += up_hcisocket_host.c
+  CSRCS += up_hcisocket.c
+endif 
+
 ifeq ($(CONFIG_RPTUN),y)
   CSRCS += up_rptun.c
 endif

arch/sim/src/sim/up_hcisocket.c

@@ -0,0 +1,247 @@
+/****************************************************************************
+ * arch/sim/src/sim/up_hcisocket.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <sys/types.h>
+
+#include <sys/socket.h>
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <nuttx/wireless/bluetooth/bt_driver.h>
+#include <nuttx/net/bluetooth.h>
+
+#include "up_internal.h"
+#include "up_hcisocket_host.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* HCI data types as defined by Linux Kernel */
+
+#define HCI_COMMAND_PKT   0x01
+#define HCI_ACLDATA_PKT   0x02
+#define HCI_SCODATA_PKT   0x03
+#define HCI_EVENT_PKT     0x04
+#define HCI_ISODATA_PKT   0x05
+#define HCI_DIAG_PKT      0xf0
+#define HCI_VENDOR_PKT    0xff
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static int bthcisock_send(FAR const struct bt_driver_s *dev,
+                          FAR struct bt_buf_s *buf);
+static int bthcisock_open(FAR const struct bt_driver_s *dev);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct bt_driver_s g_bt_hcisock =
+{
+  0,               /* head_reserve */
+  bthcisock_open,  /* open */
+  bthcisock_send   /* send */
+};
+
+static int bt_fd = -1;       /* Host HCI socket fd */
+static int host_dev_id = 0;  /* Host HCI interface number */
+
+/* Hold a receive frame buffer here. This allows us to not allocate and free
+ * on every socket read since most of the time there will be no data to
+ * actually process.
+ */
+
+struct bt_buf_s *read_buf = NULL;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+static int bthcisock_send(FAR const struct bt_driver_s *dev,
+                          FAR struct bt_buf_s *buf)
+{
+  uint8_t pkt_type;
+
+  switch (buf->type)
+    {
+      case BT_CMD:
+        {
+          pkt_type = HCI_COMMAND_PKT;
+          break;
+        }
+
+      case BT_ACL_OUT:
+        {
+          pkt_type = HCI_ACLDATA_PKT;
+          break;
+        }
+
+      default:
+        {
+          wlerr("Unexpected HCI packet type %d", buf->type);
+          return buf->len;
+        }
+    }
+
+  if (bthcisock_host_send(bt_fd, pkt_type, buf->data, buf->len) < 0)
+    {
+      return -1;
+    }
+
+  return buf->len;
+}
+
+static int bthcisock_open(FAR const struct bt_driver_s *dev)
+{
+  int fd = bthcisock_host_open(host_dev_id);
+  if (fd < 0)
+    {
+      return -1;
+    }
+
+  bt_fd = fd;
+  return OK;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: bthcisock_register
+ *
+ * Description:
+ *   Register the Linux HCI interface with the Bluetooth stack
+ *
+ * Input Parameters:
+ *   dev_id: This is the interface number known to the Linux Kernel
+ *
+ * Returned Value:
+ *   Zero is returned on success; a negated errno value is returned on any
+ *   failure.
+ *
+ ****************************************************************************/
+
+int bthcisock_register(int dev_id)
+{
+  /* Register the driver with the Bluetooth stack */
+
+  host_dev_id = dev_id;
+  return bt_netdev_register(&g_bt_hcisock);
+}
+
+/****************************************************************************
+ * Name: bthcisock_loop
+ *
+ * Description:
+ *   Feed pending packets on the host sockets into the Bluetooth stack.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   Zero is returned on success; a negated errno value is returned on any
+ *   failure.
+ *
+ ****************************************************************************/
+
+int bthcisock_loop()
+{
+  uint8_t type;
+  int len;
+
+  if (bt_fd < 0)
+    {
+      /* Internal socket has not yet been created */
+
+      return -EBADF;
+    }
+
+  if (read_buf == NULL)
+    {
+      /* NOTE: This shared allocation only works because the allocation size
+       * is currently the same for all frame types.  If this changes we will
+       * need to allocate for the largest frame or use an intermediate buffer
+       * to copy from
+       */
+
+      read_buf = bt_buf_alloc(BT_DUMMY, NULL, 0);
+      if (read_buf == NULL)
+        {
+          wlerr("ERROR: Failed to allocate buffer\n");
+          return -ENOMEM;
+        }
+    }
+
+  len = bthcisock_host_read(bt_fd, &type, read_buf->data,
+                            BLUETOOTH_MAX_FRAMELEN);
+  if (len < 0)
+    {
+      return OK;
+    }
+
+  read_buf->len = len;
+
+  switch (type)
+    {
+      case HCI_EVENT_PKT:
+        {
+          read_buf->type = BT_EVT;
+          break;
+        }
+
+      case HCI_ACLDATA_PKT:
+        {
+          read_buf->type = BT_ACL_IN;
+          break;
+        }
+
+      default:
+        {
+          wlerr("Unknown packet type %d\n", type);
+          return OK;
+        }
+    }
+
+    bt_hci_receive(read_buf);
+
+    /* Make sure to allocate a new buffer for the next read.  Bluetooth
+     * stack will clean up the allocation of this buffer when it has been
+     * handled.
+     */
+
+    read_buf = NULL;
+    return OK;
+}