sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
7e05d5e9c7
nuttx/drivers/wireless/bluetooth/bt_uart.c

420 lines
11 KiB
C
Raw Blame History

/****************************************************************************
* drivers/wireless/bluetooth/btuart.c
* UART based Bluetooth driver
*
* Copyright (C) 2018 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Ported from the Intel/Zephyr arduino101_firmware_source-v1.tar package
* where the code was released with a compatible 3-clause BSD license:
*
* Copyright (c) 2016, Intel Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stddef.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/kmalloc.h>
#include <nuttx/wireless/bt_core.h>
#include <nuttx/wireless/bt_hci.h>
#include <nuttx/wireless/bt_driver.h>
#include <nuttx/wireless/bt_uart.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define H4_HEADER_SIZE 1
#define H4_CMD 0x01
#define H4_ACL 0x02
#define H4_SCO 0x03
#define H4_EVT 0x04
/****************************************************************************
* Private Types
****************************************************************************/
struct btuart_upperhalf_s
{
/* This structure must appear first in the structure so that this structure
* is cast compatible with struct bt_driver_s.
*/
struct bt_driver_s dev;
/* The cached lower half interface */
FAR const struct btuart_lowerhalf_s *lower;
};
/****************************************************************************
* Private Functions
****************************************************************************/
static ssize_t btuart_read(FAR struct btuart_upperhalf_s *upper,
FAR uint8_t *buffer, size_t buflen,
size_t minread)
{
FAR const struct btuart_lowerhalf_s *lower;
ssize_t nread;
ssize_t ntotal = 0;
DEBUGASSERT(upper != NULL && upper->lower != NULL);
lower = upper->lower;
DEBUGASSERT(lower->read != NULL);
while (buflen > 0)
{
nread = lower->read(lower, buffer, buflen);
if (nread == 0)
{
wlinfo("Got zero bytes from UART\n");
if (ntotal < minread)
{
continue;
}
break;
}
else if (nread < 0)
{
return nread;
}
wlinfo("read %ld remaining %lu\n",
(long)nread, (unsigned long)(buflen - nread));
buflen -= nread;
ntotal += nread;
buffer += nread;
}
return ntotal;
}
static FAR struct bt_buf_s *btuart_evt_recv(FAR struct btuart_upperhalf_s *upper,
FAR int *remaining)
{
FAR struct bt_buf_s *buf;
struct bt_hci_evt_hdr_s hdr;
ssize_t nread;
/* We can ignore the return value since we pass buflen == minread */
nread = btuart_read(upper, (FAR uint8_t *)&hdr,
sizeof(struct bt_hci_evt_hdr_s),
sizeof(struct bt_hci_evt_hdr_s));
if (nread < 0)
{
return NULL;
}
*remaining = hdr.len;
buf = bt_buf_alloc(BT_EVT, NULL, 0);
if (buf != NULL)
{
memcpy(bt_buf_extend(buf, sizeof(struct bt_hci_evt_hdr_s)), &hdr,
sizeof(struct bt_hci_evt_hdr_s));
}
else
{
wlerr("ERROR: No available event buffers!\n");
}
wlinfo("len %u\n", hdr.len);
return buf;
}
static FAR struct bt_buf_s *btuart_acl_recv(FAR struct btuart_upperhalf_s *upper,
FAR int *remaining)
{
FAR struct bt_buf_s *buf;
struct bt_hci_acl_hdr_s hdr;
ssize_t nread;
/* We can ignore the return value since we pass buflen == minread */
nread = btuart_read(upper, (FAR uint8_t *)&hdr,
sizeof(struct bt_hci_acl_hdr_s),
sizeof(struct bt_hci_acl_hdr_s));
if (nread < 0)
{
return NULL;
}
buf = bt_buf_alloc(BT_ACL_IN, NULL, 0);
if (buf)
{
memcpy(bt_buf_extend(buf, sizeof(struct bt_hci_acl_hdr_s)), &hdr,
sizeof(struct bt_hci_acl_hdr_s));
}
else
{
wlerr("ERROR: No available ACL buffers!\n");
}
*remaining = BT_LE162HOST(hdr.len);
wlinfo("len %u\n", *remaining);
return buf;
}
static void btuart_interrupt(FAR const struct btuart_lowerhalf_s *lower,
FAR void *arg)
{
FAR struct btuart_upperhalf_s *upper;
static FAR struct bt_buf_s *buf;
static int remaining;
ssize_t nread;
DEBUGASSERT(lower != NULL && lower->rxdrain != NULL && arg != NULL);
upper = (FAR struct btuart_upperhalf_s *)arg;
/* Beginning of a new packet */
while (remaining > 0)
{
uint8_t type;
/* Get packet type */
nread = btuart_read(upper, &type, 1, 0);
if (nread != sizeof(type))
{
wlwarn("WARNING: Unable to read H4 packet type\n");
continue;
}
switch (type)
{
case H4_EVT:
buf = btuart_evt_recv(upper, &remaining);
break;
case H4_ACL:
buf = btuart_acl_recv(upper, &remaining);
break;
default:
wlerr("ERROR: Unknown H4 type %u\n", type);
return;
}
if (buf != NULL && remaining > bt_buf_tailroom(buf))
{
wlerr("ERROR: Not enough space in buffer\n");
goto failed;
}
wlinfo("Need to get %u bytes\n", remaining);
}
if (buf == NULL)
{
nread = lower->rxdrain(lower);
wlwarn("WARNING: Discarded %ld bytes\n", (long)nread);
remaining -= nread;
}
nread = btuart_read(upper, bt_buf_tail(buf), remaining, 0);
buf->len += nread;
remaining -= nread;
wlinfo("Received %ld bytes\n", (long)nread);
if (remaining == 0)
{
wlinfo("Full packet received\n");
/* Pass buffer to the stack */
bt_hci_receive(buf);
buf = NULL;
}
return;
failed:
bt_buf_release(buf);
remaining = 0;
buf = NULL;
return;
}
static int btuart_send(FAR const struct bt_driver_s *dev,
FAR struct bt_buf_s *buf)
{
FAR struct btuart_upperhalf_s *upper;
FAR const struct btuart_lowerhalf_s *lower;
FAR uint8_t *type;
ssize_t nwritten;
upper = (FAR struct btuart_upperhalf_s *)dev;
DEBUGASSERT(upper != NULL && upper->lower != NULL);
lower = upper->lower;
if (bt_buf_headroom(buf) < H4_HEADER_SIZE)
{
wlerr("Not enough headroom in buffer\n");
return -EINVAL;
}
type = bt_buf_provide(buf, 1);
switch (buf->type)
{
case BT_CMD:
*type = H4_CMD;
break;
case BT_ACL_OUT:
*type = H4_ACL;
break;
case BT_EVT:
*type = H4_EVT;
break;
default:
wlerr("Unknown buf type %u\n", buf->type);
return -EINVAL;
}
nwritten = lower->write(lower, buf->data, buf->len);
if (nwritten == buf->len)
{
return OK;
}
if (nwritten < 0)
{
return (int)nwritten;
}
return -EIO;
}
static int btuart_open(FAR const struct bt_driver_s *dev)
{
FAR struct btuart_upperhalf_s *upper;
FAR const struct btuart_lowerhalf_s *lower;
upper = (FAR struct btuart_upperhalf_s *)dev;
DEBUGASSERT(upper != NULL && upper->lower != NULL);
lower = upper->lower;
/* Disable Tx and Rx interrupts */
lower->txenable(lower, false);
lower->rxenable(lower, false);
/* Drain any cached Rx data */
(void)lower->rxdrain(lower);
/* Enable Rx interrupts */
lower->rxenable(lower, true);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: btuart_register
*
* Description:
* Create the UART-based Bluetooth device and register it with the
* Bluetooth stack.
*
* Input Parameters:
* lower - an instance of the lower half driver interface
*
* Returned Value:
* Zero is returned on success; a negated errno value is returned on any
* failure.
*
****************************************************************************/
int btuart_register(FAR const struct btuart_lowerhalf_s *lower)
{
FAR struct btuart_upperhalf_s *upper;
int ret;
DEBUGASSERT(lower != NULL);
/* Allocate a new instance of the upper half driver state structure */
upper = (FAR struct btuart_upperhalf_s *)
kmm_zalloc(sizeof(struct btuart_upperhalf_s));
if (upper == NULL)
{
wlerr("ERROR: Failed to allocate upper-half state\n");
return -ENOMEM;
}
/* Initialize the upper half driver state */
upper->dev.head_reserve = H4_HEADER_SIZE;
upper->dev.open = btuart_open;
upper->dev.send = btuart_send;
upper->lower = lower;
/* Attach the interrupt handler */
lower->attach(lower, btuart_interrupt, upper);
/* And register the driver with the Bluetooth stack */
ret = bt_driver_register(&upper->dev);
if (ret < 0)
{
kmm_free(upper);
}
return ret;
}
Reference in New Issue View Git Blame Copy Permalink