nuttx/wireless/ieee802154/mac802154_device.c
2017-04-05 13:28:35 -06:00

578 lines
16 KiB
C

/****************************************************************************
* drivers/ieee802154/mac802154_device.c
*
* Copyright (C) 2017 Verge Inc. All rights reserved.
* Author: Anthony Merlino <anthony@vergeaero.com>
*
* 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 NuttX 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 OWNER 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 <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <time.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include <nuttx/wireless/ieee802154/ieee802154_mac.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Device naming ************************************************************/
#define DEVNAME_FMT "/dev/ieee%d"
#define DEVNAME_FMTLEN (9 + 3 + 1)
/****************************************************************************
* Private Types
****************************************************************************/
struct mac802154_devwrapper_s
{
FAR struct ieee802154_mac_s *md_mac; /* Saved binding to the mac layer */
sem_t md_exclsem; /* Exclusive device access */
/* The following is a singly linked list of open references to the
* MAC device.
*/
FAR struct mac802154_open_s *md_open;
FAR struct mac802154dev_dwait_s *md_dwait;
};
/* This structure describes the state of one open mac driver instance */
struct mac802154_open_s
{
/* Supports a singly linked list */
FAR struct mac802154_open_s *md_flink;
/* The following will be true if we are closing */
volatile bool md_closing;
};
struct mac802154dev_dwait_s
{
uint8_t mw_handle; /* The msdu handle identifying the frame */
sem_t mw_sem; /* The semaphore used to signal the completion */
int status; /* The success/error of the transaction */
/* Supports a singly linked list */
FAR struct mac802154dev_dwait_s *mw_flink;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Semaphore helpers */
static inline int mac802154dev_takesem(sem_t *sem);
#define mac802154dev_givesem(s) sem_post(s);
static int mac802154dev_open(FAR struct file *filep);
static int mac802154dev_close(FAR struct file *filep);
static ssize_t mac802154dev_read(FAR struct file *filep, FAR char *buffer,
size_t len);
static ssize_t mac802154dev_write(FAR struct file *filep,
FAR const char *buffer, size_t len);
static int mac802154dev_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations mac802154dev_fops =
{
mac802154dev_open , /* open */
mac802154dev_close, /* close */
mac802154dev_read , /* read */
mac802154dev_write, /* write */
NULL, /* seek */
mac802154dev_ioctl /* ioctl */
#ifndef CONFIG_DISABLE_POLL
, NULL /* poll */
#endif
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
, NULL /* unlink */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: mac802154dev_semtake
*
* Description:
* Acquire the semaphore used for access serialization.
*
****************************************************************************/
static inline int mac802154dev_takesem(sem_t *sem)
{
/* Take a count from the semaphore, possibly waiting */
if (sem_wait(sem) < 0)
{
/* EINTR is the only error that we expect */
int errcode = get_errno();
DEBUGASSERT(errcode == EINTR);
return -errcode;
}
return OK;
}
/****************************************************************************
* Name: mac802154dev_open
*
* Description:
* Open the 802.15.4 MAC character device.
*
****************************************************************************/
static int mac802154dev_open(FAR struct file *filep)
{
FAR struct inode *inode;
FAR struct mac802154_devwrapper_s *dev;
FAR struct mac802154_open_s *opriv;
int ret;
DEBUGASSERT(filep != NULL && filep->f_inode != NULL);
inode = filep->f_inode;
dev = inode->i_private;
DEBUGASSERT(dev != NULL);
/* Get exclusive access to the MAC driver data structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret);
return ret;
}
/* Allocate a new open struct */
opriv = (FAR struct mac802154_open_s *)
kmm_zalloc(sizeof(struct mac802154_open_s));
if (!opriv)
{
wlerr("ERROR: Failed to allocate new open struct\n");
ret = -ENOMEM;
goto errout_with_sem;
}
/* Attach the open struct to the device */
opriv->md_flink = dev->md_open;
dev->md_open = opriv;
/* Attach the open struct to the file structure */
filep->f_priv = (FAR void *)opriv;
ret = OK;
errout_with_sem:
mac802154dev_givesem(&dev->md_exclsem);
return ret;
}
/****************************************************************************
* Name: mac802154dev_close
*
* Description:
* Close the 802.15.4 MAC character device.
*
****************************************************************************/
static int mac802154dev_close(FAR struct file *filep)
{
FAR struct inode *inode;
FAR struct mac802154_devwrapper_s *dev;
FAR struct mac802154_open_s *opriv;
FAR struct mac802154_open_s *curr;
FAR struct mac802154_open_s *prev;
irqstate_t flags;
bool closing;
int ret;
DEBUGASSERT(filep && filep->f_priv && filep->f_inode);
opriv = filep->f_priv;
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
dev = (FAR struct mac802154_devwrapper_s *)inode->i_private;
/* Handle an improbable race conditions with the following atomic test
* and set.
*
* This is actually a pretty feeble attempt to handle this. The
* improbable race condition occurs if two different threads try to
* close the joystick driver at the same time. The rule: don't do
* that! It is feeble because we do not really enforce stale pointer
* detection anyway.
*/
flags = enter_critical_section();
closing = opriv->md_closing;
opriv->md_closing = true;
leave_critical_section(flags);
if (closing)
{
/* Another thread is doing the close */
return OK;
}
/* Get exclusive access to the driver structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154_takesem failed: %d\n", ret);
return ret;
}
/* Find the open structure in the list of open structures for the device */
for (prev = NULL, curr = dev->md_open;
curr && curr != opriv;
prev = curr, curr = curr->md_flink);
DEBUGASSERT(curr);
if (!curr)
{
wlerr("ERROR: Failed to find open entry\n");
ret = -ENOENT;
goto errout_with_exclsem;
}
/* Remove the structure from the device */
if (prev)
{
prev->md_flink = opriv->md_flink;
}
else
{
dev->md_open = opriv->md_flink;
}
/* And free the open structure */
kmm_free(opriv);
ret = OK;
errout_with_exclsem:
mac802154dev_givesem(&dev->md_exclsem);
return ret;
}
/****************************************************************************
* Name: mac802154dev_read
*
* Description:
* Return the last received packet.
*
****************************************************************************/
static ssize_t mac802154dev_read(FAR struct file *filep, FAR char *buffer,
size_t len)
{
FAR struct inode *inode;
FAR struct mac802154_devwrapper_s *dev;
int ret;
DEBUGASSERT(filep && filep->f_inode);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
dev = (FAR struct mac802154_devwrapper_s *)inode->i_private;
/* Check to make sure that the buffer is big enough to hold at least one
* packet.
*/
if (len < sizeof(struct ieee802154_frame_s))
{
wlerr("ERROR: buffer too small: %lu\n", (unsigned long)len);
return -EINVAL;
}
/* Get exclusive access to the driver structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret);
return ret;
}
/* TODO: Add code to read a packet and return it */
ret = -ENOTSUP;
mac802154dev_givesem(&dev->md_exclsem);
return ret;
}
/****************************************************************************
* Name: mac802154dev_write
*
* Description:
* Send a packet over the IEEE802.15.4 network.
*
****************************************************************************/
static ssize_t mac802154dev_write(FAR struct file *filep,
FAR const char *buffer, size_t len)
{
FAR struct inode *inode;
FAR struct mac802154_devwrapper_s *dev;
FAR struct ieee802154_data_req_s *req;
struct mac802154dev_dwait_s dwait;
int ret;
DEBUGASSERT(filep && filep->f_inode);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
dev = (FAR struct mac802154_devwrapper_s *)inode->i_private;
/* Check to make sure that the buffer is big enough to hold at least one
* packet.
*/
if (len < sizeof(struct ieee802154_frame_s))
{
wlerr("ERROR: buffer too small: %lu\n", (unsigned long)len);
return -EINVAL;
}
DEBUGASSERT(buffer != NULL);
frame = *(FAR struct ieee802154_frame_s *)buffer;
/* Get exclusive access to the driver structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret);
return ret;
}
/* Setup the wait struct */
dwait.mw_handle = req->msdu_handle;
/* Link the wait struct */
dwait.mw_flink = dev->md_dwait;
dev->md_wait = &dwait;
/* Pass the request to the MAC layer */
ret = dev->md_mac->ops.req_data(dev->md_mac, req);
mac802154dev_givesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: req_data failed %d\n", ret);
return ret;
}
/* Wait for the DATA.confirm callback to be called for our handle */
sem_wait(dwait.mw_sem);
/* The unlinking of the wait struct happens inside the callback. This
* is more efficient since it will already have to find the struct in
* the list in order to perform the sem_post.
*/
return dwait.status;
}
/****************************************************************************
* Name: mac802154dev_ioctl
*
* Description:
* Control the MAC layer via MLME IOCTL commands.
*
****************************************************************************/
static int mac802154dev_ioctl(FAR struct file *filep, int cmd,
unsigned long arg)
{
FAR struct inode *inode;
FAR struct mac802154_devwrapper_s *dev;
FAR struct ieee802154_mac_s *mac;
int ret;
DEBUGASSERT(filep != NULL && filep->f_priv != NULL &&
filep->f_inode != NULL);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
dev = (FAR struct mac802154_devwrapper_s *)inode->i_private;
/* Get exclusive access to the driver structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret);
return ret;
}
/* Handle the ioctl command */
switch (cmd)
{
default:
wlerr("ERROR: Unrecognized command %ld\n", cmd);
ret = -EINVAL;
break;
}
mac802154dev_givesem(&dev->md_exclsem);
return ret;
}
void mac802154dev_conf_data(FAR struct ieee802154_mac_s *mac,
FAR struct ieee802154_data_conf_s *conf)
{
FAR struct mac802154_devwrapper_s *dev;
FAR struct mac802154dev_dwait_s *curr;
FAR struct mac802154dev_dwait_s *prev;
int ret;
/* Get the dev from the callback context. This should have been set when
* the char driver was registered.
*/
dev = mac->cbs.cb_context;
/* Get exclusive access to the driver structure */
ret = mac802154dev_takesem(&dev->md_exclsem);
if (ret < 0)
{
wlerr("ERROR: mac802154dev_takesem failed: %d\n", ret);
return ret;
}
/* Search to see if there is a dwait pending for this transaction */
for (prev = NULL, curr = dev->md_dwait;
curr && curr->mw_handle != conf->msdu_handle;
prev = curr, curr = curr->mw_flink);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mac802154dev_register
*
* Description:
* Register a character driver to access the IEEE 802.15.4 MAC layer from
* user-space
*
* Input Parameters:
* mac - Pointer to the mac layer struct to be registerd.
* minor - The device minor number. The IEEE802.15.4 MAC character device
* will be registered as /dev/ieeeN where N is the minor number
*
* Returned Values:
* Zero (OK) is returned on success. Otherwise a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int mac802154dev_register(FAR struct ieee802154_mac_s *mac, int minor)
{
FAR struct mac802154_devwrapper_s *dev;
char devname[DEVNAME_FMTLEN];
int ret;
dev = kmm_zalloc(sizeof(struct mac802154_devwrapper_s));
if (!dev)
{
wlerr("ERROR: Failed to allocate device structure\n");
return -ENOMEM;
}
/* Initialize the new mac driver instance */
dev->md_mac = mac;
sem_init(&dev->md_exclsem, 0, 1); /* Allow the device to be opened once
* before blocking */
/* Create the character device name */
snprintf(devname, DEVNAME_FMTLEN, DEVNAME_FMT, minor);
/* Register the mac character driver */
ret = register_driver(devname, &mac802154dev_fops, 0666, dev);
if (ret < 0)
{
wlerr("ERROR: register_driver failed: %d\n", ret);
goto errout_with_priv;
}
return OK;
errout_with_priv:
sem_destroy(&dev->md_exclsem);
kmm_free(dev);
return ret;
}