OrgApache/incubator-nuttx
OrgApache
/
incubator-nuttx
mirror of https://github.com/apache/incubator-nuttx.git
1
0
Fork 0
Code Issues Releases Wiki Activity
incubator-nuttx/drivers/timers/capture.c

481 lines
13 KiB
C
Raw Blame History

/****************************************************************************
* drivers/timers/capture.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 <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
#include <nuttx/arch.h>
#include <nuttx/mutex.h>
#include <nuttx/timers/capture.h>
#include <arch/irq.h>
#ifdef CONFIG_CAPTURE
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Debug ********************************************************************/
/****************************************************************************
* Private Type Definitions
****************************************************************************/
/* This structure describes the state of the upper half driver */
struct cap_upperhalf_s
{
uint8_t crefs; /* The number of times the device has been opened */
uint8_t nchan; /* The number of channels, only invalid for multi channels */
mutex_t lock; /* Supports mutual exclusion */
FAR struct cap_lowerhalf_s **lower; /* lower-half state */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int cap_open(FAR struct file *filep);
static int cap_close(FAR struct file *filep);
static ssize_t cap_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t cap_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
static int cap_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_capops =
{
cap_open, /* open */
cap_close, /* close */
cap_read, /* read */
cap_write, /* write */
NULL, /* seek */
cap_ioctl, /* ioctl */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: cap_open
*
* Description:
* This function is called whenever the PWM Capture device is opened.
*
****************************************************************************/
static int cap_open(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct cap_upperhalf_s *upper = inode->i_private;
uint8_t tmp;
int ret;
/* Get exclusive access to the device structures */
ret = nxmutex_lock(&upper->lock);
if (ret < 0)
{
goto errout;
}
/* Increment the count of references to the device. If this is the first
* time that the driver has been opened for this device, then initialize
* the device.
*/
tmp = upper->crefs + 1;
if (tmp == 0)
{
/* More than 255 opens; uint8_t overflows to zero */
ret = -EMFILE;
goto errout_with_lock;
}
/* Check if this is the first time that the driver has been opened. */
if (tmp == 1)
{
FAR struct cap_lowerhalf_s **lower = upper->lower;
uint8_t i;
for (i = 0; i < upper->nchan; i++)
{
ret = lower[i]->ops->start(lower[i]);
if (ret < 0)
{
while (i-- > 0)
{
lower[i]->ops->stop(lower[i]);
}
goto errout_with_lock;
}
}
}
/* Save the new open count on success */
upper->crefs = tmp;
ret = OK;
errout_with_lock:
nxmutex_unlock(&upper->lock);
errout:
return ret;
}
/****************************************************************************
* Name: cap_close
*
* Description:
* This function is called when the PWM Capture device is closed.
*
****************************************************************************/
static int cap_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct cap_upperhalf_s *upper = inode->i_private;
int ret;
/* Get exclusive access to the device structures */
ret = nxmutex_lock(&upper->lock);
if (ret < 0)
{
goto errout;
}
/* Decrement the references to the driver. If the reference count will
* decrement to 0, then uninitialize the driver.
*/
if (upper->crefs > 1)
{
upper->crefs--;
}
else
{
FAR struct cap_lowerhalf_s **lower = upper->lower;
uint8_t i;
/* There are no more references to the port */
upper->crefs = 0;
for (i = 0; i < upper->nchan; i++)
{
/* Disable the PWM Capture device */
lower[i]->ops->stop(lower[i]);
}
}
nxmutex_unlock(&upper->lock);
ret = OK;
errout:
return ret;
}
/****************************************************************************
* Name: cap_read
*
* Description:
* A dummy read method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t cap_read(FAR struct file *filep,
FAR char *buffer,
size_t buflen)
{
/* Return zero -- usually meaning end-of-file */
return 0;
}
/****************************************************************************
* Name: cap_write
*
* Description:
* A dummy write method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t cap_write(FAR struct file *filep,
FAR const char *buffer,
size_t buflen)
{
/* Return a failure */
return -EPERM;
}
/****************************************************************************
* Name: cap_ioctl
*
* Description:
* The standard ioctl method.
* This is where ALL of the PWM Capture work is done.
*
****************************************************************************/
static int cap_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode = filep->f_inode;
FAR struct cap_upperhalf_s *upper;
FAR struct cap_lowerhalf_s **lower;
int ret;
uint8_t i;
cpinfo("cmd: %d arg: %ld\n", cmd, arg);
upper = inode->i_private;
DEBUGASSERT(upper != NULL);
lower = upper->lower;
DEBUGASSERT(lower != NULL);
/* Get exclusive access to the device structures */
ret = nxmutex_lock(&upper->lock);
if (ret < 0)
{
return ret;
}
/* Handle built-in ioctl commands */
switch (cmd)
{
/* CAPIOC_DUTYCYCLE - Get the pwm duty from the capture.
* Argument: int8_t pointer to the location to return the duty.
*/
case CAPIOC_DUTYCYCLE:
{
FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg);
DEBUGASSERT(ptr);
for (i = 0; i < upper->nchan; i++)
{
DEBUGASSERT(lower[i]->ops->getduty != NULL);
ret = lower[i]->ops->getduty(lower[i], &ptr[i]);
if (ret < 0)
{
break;
}
}
}
break;
/* CAPIOC_FREQUENCE - Get the pulse frequence from the capture.
* Argument: int32_t pointer to the location to return the frequence.
*/
case CAPIOC_FREQUENCE:
{
FAR uint32_t *ptr = (FAR uint32_t *)((uintptr_t)arg);
DEBUGASSERT(ptr);
for (i = 0; i < upper->nchan; i++)
{
DEBUGASSERT(lower[i]->ops->getfreq != NULL);
ret = lower[i]->ops->getfreq(lower[i], &ptr[i]);
if (ret < 0)
{
break;
}
}
}
break;
/* CAPIOC_EDGES - Get the pwm edges from the capture.
* Argument: int32_t pointer to the location to return the edges.
*/
case CAPIOC_EDGES:
{
FAR uint32_t *ptr = (FAR uint32_t *)((uintptr_t)arg);
DEBUGASSERT(ptr);
for (i = 0; i < upper->nchan; i++)
{
DEBUGASSERT(lower[i]->ops->getedges != NULL);
ret = lower[i]->ops->getedges(lower[i], &ptr[i]);
if (ret < 0)
{
break;
}
}
}
break;
/* CAPIOC_ALL - Get the pwm duty, pulse frequence, pwm edges, from
* the capture.
* Argument: A reference to struct cap_all_s.
*/
case CAPIOC_ALL:
{
FAR struct cap_all_s *ptr =
(FAR struct cap_all_s *)((uintptr_t)arg);
DEBUGASSERT(ptr);
for (i = 0 ; i < upper->nchan ; i++)
{
ret = lower[i]->ops->getduty(lower[i], &ptr[i].duty);
if (ret < 0)
{
break;
}
ret = lower[i]->ops->getfreq(lower[i], &ptr[i].freq);
if (ret < 0)
{
break;
}
ret = lower[i]->ops->getedges(lower[i], &ptr[i].edges);
if (ret < 0)
{
break;
}
}
}
break;
/* Any unrecognized IOCTL commands might be platform-specific ioctl
* commands
*/
default:
{
cperr("Forwarding unrecognized cmd: %d arg: %ld\n", cmd, arg);
}
break;
}
nxmutex_unlock(&upper->lock);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: cap_register
*
* Description:
* Register the PWM Capture lower half device as 'devpath'
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/cap0"
* lower - An instance of the lower half interface
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure. The following
* possible error values may be returned (most are returned by
* register_driver()):
*
* EINVAL - 'path' is invalid for this operation
* EEXIST - An inode already exists at 'path'
* ENOMEM - Failed to allocate in-memory resources for the operation
*
****************************************************************************/
int cap_register(FAR const char *devpath, FAR struct cap_lowerhalf_s *lower)
{
FAR struct cap_upperhalf_s *upper;
/* Allocate the upper-half data structure */
upper = (FAR struct cap_upperhalf_s *)
kmm_zalloc(sizeof(struct cap_upperhalf_s) +
sizeof(FAR struct cap_lowerhalf_s *));
if (!upper)
{
return -ENOMEM;
}
/* Initialize the PWM Capture device structure
* (it was already zeroed by kmm_zalloc())
*/
nxmutex_init(&upper->lock);
upper->lower = (FAR struct cap_lowerhalf_s **)(upper + 1);
upper->lower[0] = lower;
upper->nchan = 1;
/* Register the PWM Capture device */
return register_driver(devpath, &g_capops, 0666, upper);
}
int cap_register_multiple(FAR const char *devpath,
FAR struct cap_lowerhalf_s **lower, int n)
{
FAR struct cap_upperhalf_s *upper;
/* Allocate the upper-half data structure */
upper = (FAR struct cap_upperhalf_s *)
kmm_zalloc(sizeof(struct cap_upperhalf_s));
if (!upper)
{
return -ENOMEM;
}
/* Initialize the PWM Capture device structure
* (it was already zeroed by kmm_zalloc())
*/
nxmutex_init(&upper->lock);
upper->lower = lower;
upper->nchan = n;
/* Register the PWM Capture device */
return register_driver(devpath, &g_capops, 0666, upper);
}
#endif /* CONFIG_CAPTURE */
Reference in New Issue View Git Blame Copy Permalink