incubator-nuttx/drivers/timers/watchdog.c

700 lines
19 KiB
C

/****************************************************************************
* drivers/timers/watchdog.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 <string.h>
#include <fcntl.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/fs/fs.h>
#include <nuttx/irq.h>
#include <nuttx/kmalloc.h>
#include <nuttx/power/pm.h>
#include <nuttx/semaphore.h>
#include <nuttx/wdog.h>
#include <nuttx/wqueue.h>
#include <nuttx/timers/watchdog.h>
#ifdef CONFIG_WATCHDOG
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
#define WATCHDOG_AUTOMONITOR_TIMEOUT_MSEC \
(1000 * CONFIG_WATCHDOG_AUTOMONITOR_TIMEOUT)
#if (CONFIG_WATCHDOG_AUTOMONITOR_TIMEOUT == \
CONFIG_WATCHDOG_AUTOMONITOR_PING_INTERVAL)
#define WATCHDOG_AUTOMONITOR_PING_INTERVAL \
SEC2TICK(CONFIG_WATCHDOG_AUTOMONITOR_TIMEOUT / 2)
#else
#define WATCHDOG_AUTOMONITOR_PING_INTERVAL \
SEC2TICK(CONFIG_WATCHDOG_AUTOMONITOR_PING_INTERVAL)
#endif
#endif
/****************************************************************************
* Private Type Definitions
****************************************************************************/
/* This structure describes the state of the upper half driver */
struct watchdog_upperhalf_s
{
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
#if defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_TIMER)
struct wdog_s wdog;
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_WORKER)
struct work_s work;
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_IDLE)
struct pm_callback_s idle;
#endif
bool monitor;
#endif
uint8_t crefs; /* The number of times the device has been opened */
sem_t exclsem; /* Supports mutual exclusion */
FAR char *path; /* Registration path */
/* The contained lower-half driver */
FAR struct watchdog_lowerhalf_s *lower;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int wdog_open(FAR struct file *filep);
static int wdog_close(FAR struct file *filep);
static ssize_t wdog_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t wdog_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
static int wdog_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_wdogops =
{
wdog_open, /* open */
wdog_close, /* close */
wdog_read, /* read */
wdog_write, /* write */
NULL, /* seek */
wdog_ioctl, /* ioctl */
NULL /* poll */
};
/****************************************************************************
* Private Functions
****************************************************************************/
#if defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_CAPTURE)
static int watchdog_automonitor_capture(int irq, FAR void *context,
FAR void *arg)
{
FAR struct watchdog_upperhalf_s *upper = arg;
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (upper->monitor)
{
lower->ops->keepalive(lower);
}
return 0;
}
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_TIMER)
static void watchdog_automonitor_timer(wdparm_t arg)
{
FAR struct watchdog_upperhalf_s *upper = (FAR void *)arg;
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (upper->monitor)
{
lower->ops->keepalive(lower);
wd_start(&upper->wdog, WATCHDOG_AUTOMONITOR_PING_INTERVAL,
watchdog_automonitor_timer, (wdparm_t)upper);
}
}
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_WORKER)
static void watchdog_automonitor_worker(FAR void *arg)
{
FAR struct watchdog_upperhalf_s *upper = arg;
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (upper->monitor)
{
lower->ops->keepalive(lower);
work_queue(LPWORK, &upper->work, watchdog_automonitor_worker,
upper, WATCHDOG_AUTOMONITOR_PING_INTERVAL);
}
}
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_IDLE)
static void watchdog_automonitor_idle(FAR struct pm_callback_s *cb,
int domain, enum pm_state_e pmstate)
{
FAR struct watchdog_upperhalf_s *upper = (FAR void *)cb;
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (upper->monitor)
{
lower->ops->keepalive(lower);
}
}
#endif
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
static void watchdog_automonitor_start(FAR struct watchdog_upperhalf_s
*upper)
{
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (!upper->monitor)
{
upper->monitor = true;
#if defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_CAPTURE)
lower->ops->capture(lower, watchdog_automonitor_capture);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_TIMER)
wd_start(&upper->wdog, WATCHDOG_AUTOMONITOR_PING_INTERVAL,
watchdog_automonitor_timer, (wdparm_t)upper);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_WORKER)
work_queue(LPWORK, &upper->work, watchdog_automonitor_worker,
upper, WATCHDOG_AUTOMONITOR_PING_INTERVAL);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_IDLE)
upper->idle.notify = watchdog_automonitor_idle;
pm_register(&upper->idle);
#endif
if (lower->ops->settimeout)
{
lower->ops->settimeout(lower, WATCHDOG_AUTOMONITOR_TIMEOUT_MSEC);
}
lower->ops->start(lower);
}
}
static void watchdog_automonitor_stop(FAR struct watchdog_upperhalf_s *upper)
{
FAR struct watchdog_lowerhalf_s *lower = upper->lower;
if (upper->monitor)
{
upper->monitor = false;
lower->ops->stop(lower);
#if defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_CAPTURE)
lower->ops->capture(lower, NULL);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_TIMER)
wd_cancel(&upper->wdog);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_WORKER)
work_cancel(LPWORK, &upper->work);
#elif defined(CONFIG_WATCHDOG_AUTOMONITOR_BY_IDLE)
pm_unregister(&upper->idle);
#endif
}
}
#endif
/****************************************************************************
* Name: wdog_open
*
* Description:
* This function is called whenever the watchdog timer device is opened.
*
****************************************************************************/
static int wdog_open(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct watchdog_upperhalf_s *upper = inode->i_private;
uint8_t tmp;
int ret;
wdinfo("crefs: %d\n", upper->crefs);
/* Get exclusive access to the device structures */
ret = nxsem_wait(&upper->exclsem);
if (ret < 0)
{
goto errout;
}
/* Increment the count of references to the device. If this 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_sem;
}
/* Save the new open count */
upper->crefs = tmp;
ret = OK;
errout_with_sem:
nxsem_post(&upper->exclsem);
errout:
return ret;
}
/****************************************************************************
* Name: wdog_close
*
* Description:
* This function is called when the watchdog timer device is closed.
*
****************************************************************************/
static int wdog_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct watchdog_upperhalf_s *upper = inode->i_private;
int ret;
wdinfo("crefs: %d\n", upper->crefs);
/* Get exclusive access to the device structures */
ret = nxsem_wait(&upper->exclsem);
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 > 0)
{
upper->crefs--;
}
nxsem_post(&upper->exclsem);
ret = OK;
errout:
return ret;
}
/****************************************************************************
* Name: wdog_read
*
* Description:
* A dummy read method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t wdog_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
/* Return zero -- usually meaning end-of-file */
return 0;
}
/****************************************************************************
* Name: wdog_write
*
* Description:
* A dummy write method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t wdog_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
return 0;
}
/****************************************************************************
* Name: wdog_ioctl
*
* Description:
* The standard ioctl method. This is where ALL of the watchdog timer
* work is done.
*
****************************************************************************/
static int wdog_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode = filep->f_inode;
FAR struct watchdog_upperhalf_s *upper;
FAR struct watchdog_lowerhalf_s *lower;
int ret;
wdinfo("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 = nxsem_wait(&upper->exclsem);
if (ret < 0)
{
return ret;
}
/* Handle built-in ioctl commands */
switch (cmd)
{
/* cmd: WDIOC_START
* Description: Start the watchdog timer
* Argument: Ignored
*/
case WDIOC_START:
{
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
watchdog_automonitor_stop(upper);
#endif
/* Start the watchdog timer, resetting the time to the current
* timeout
*/
DEBUGASSERT(lower->ops->start); /* Required */
ret = lower->ops->start(lower);
}
break;
/* cmd: WDIOC_STOP
* Description: Stop the watchdog timer
* Argument: Ignored
*/
case WDIOC_STOP:
{
/* Stop the watchdog timer */
DEBUGASSERT(lower->ops->stop); /* Required */
ret = lower->ops->stop(lower);
}
break;
/* cmd: WDIOC_GETSTATUS
* Description: Get the status of the watchdog timer.
* Argument: A writeable pointer to struct watchdog_status_s.
*/
case WDIOC_GETSTATUS:
{
FAR struct watchdog_status_s *status;
/* Get the current watchdog timer status */
if (lower->ops->getstatus) /* Optional */
{
status = (FAR struct watchdog_status_s *)((uintptr_t)arg);
if (status)
{
ret = lower->ops->getstatus(lower, status);
}
else
{
ret = -EINVAL;
}
}
else
{
ret = -ENOSYS;
}
}
break;
/* cmd: WDIOC_SETTIMEOUT
* Description: Reset the watchdog timeout to this value
* Argument: A 32-bit timeout value in milliseconds.
*/
case WDIOC_SETTIMEOUT:
{
/* Set a new timeout value (and reset the watchdog timer) */
if (lower->ops->settimeout) /* Optional */
{
ret = lower->ops->settimeout(lower, (uint32_t)arg);
}
else
{
ret = -ENOSYS;
}
}
break;
/* cmd: WDIOC_CAPTURE
* Description: Do not reset. Instead, called this handler.
* Argument: A pointer to struct watchdog_capture_s.
*/
case WDIOC_CAPTURE:
{
FAR struct watchdog_capture_s *capture;
/* Don't reset on watchdog timer timeout; instead, call this user
* provider timeout handler. NOTE: Providing handler==NULL will
* restore the reset behavior.
*/
if (lower->ops->capture) /* Optional */
{
capture = (FAR struct watchdog_capture_s *)((uintptr_t)arg);
if (capture)
{
capture->oldhandler =
lower->ops->capture(lower, capture->newhandler);
ret = OK;
}
else
{
ret = -EINVAL;
}
}
else
{
ret = -ENOSYS;
}
}
break;
/* cmd: WDIOC_KEEPALIVE
* Description: Reset the watchdog timer ("ping", "pet the dog")
* Argument: Argument: Ignored
*/
case WDIOC_KEEPALIVE:
{
/* Reset the watchdog timer to the current timeout value, prevent
* any imminent watchdog timeouts. This is sometimes referred as
* "pinging" the watchdog timer or "petting the dog".
*/
if (lower->ops->keepalive) /* Optional */
{
ret = lower->ops->keepalive(lower);
}
else
{
ret = -ENOSYS;
}
}
break;
/* Any unrecognized IOCTL commands might be platform-specific ioctl
* commands
*/
default:
{
wdinfo("Forwarding unrecognized cmd: %d arg: %ld\n", cmd, arg);
/* An ioctl commands that are not recognized by the "upper-half"
* driver are forwarded to the lower half driver through this
* method.
*/
if (lower->ops->ioctl) /* Optional */
{
ret = lower->ops->ioctl(lower, cmd, arg);
}
else
{
ret = -ENOTTY;
}
}
break;
}
nxsem_post(&upper->exclsem);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: watchdog_register
*
* Description:
* This function binds an instance of a "lower half" watchdog driver with
* the "upper half" watchdog device and registers that device so that can
* be usedby application code.
*
* When this function is called, the "lower half" driver should be in the
* disabled state (as if the stop() method had already been called).
*
* Input Parameters:
* dev path - The full path to the driver to be registers in the NuttX
* pseudo-filesystem. The recommended convention is to name all
* watchdogdrivers as "/dev/watchdog0", "/dev/watchdog1", etc. where
* the driverpath differs only in the "minor" number at the end of the
* device name.
* lower - A pointer to an instance of lower half watchdog driver. This
* instance is bound to the watchdog driver and must persists as long as
* the driver persists.
*
* Returned Value:
* On success, a non-NULL handle is returned to the caller. In the event
* of any failure, a NULL value is returned.
*
****************************************************************************/
FAR void *watchdog_register(FAR const char *path,
FAR struct watchdog_lowerhalf_s *lower)
{
FAR struct watchdog_upperhalf_s *upper;
int ret;
DEBUGASSERT(path && lower);
wdinfo("Entry: path=%s\n", path);
/* Allocate the upper-half data structure */
upper = (FAR struct watchdog_upperhalf_s *)
kmm_zalloc(sizeof(struct watchdog_upperhalf_s));
if (!upper)
{
wderr("Upper half allocation failed\n");
goto errout;
}
/* Initialize the watchdog timer device structure (it was already zeroed
* by kmm_zalloc()).
*/
nxsem_init(&upper->exclsem, 0, 1);
upper->lower = lower;
/* Copy the registration path */
upper->path = strdup(path);
if (!upper->path)
{
wderr("Path allocation failed\n");
goto errout_with_upper;
}
/* Register the watchdog timer device */
ret = register_driver(path, &g_wdogops, 0666, upper);
if (ret < 0)
{
wderr("register_driver failed: %d\n", ret);
goto errout_with_path;
}
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
watchdog_automonitor_start(upper);
#endif
return (FAR void *)upper;
errout_with_path:
kmm_free(upper->path);
errout_with_upper:
nxsem_destroy(&upper->exclsem);
kmm_free(upper);
errout:
return NULL;
}
/****************************************************************************
* Name: watchdog_unregister
*
* Description:
* This function can be called to disable and unregister the watchdog
* device driver.
*
* Input Parameters:
* handle - This is the handle that was returned by watchdog_register()
*
* Returned Value:
* None
*
****************************************************************************/
void watchdog_unregister(FAR void *handle)
{
FAR struct watchdog_upperhalf_s *upper;
FAR struct watchdog_lowerhalf_s *lower;
/* Recover the pointer to the upper-half driver state */
upper = (FAR struct watchdog_upperhalf_s *)handle;
DEBUGASSERT(upper != NULL);
lower = upper->lower;
DEBUGASSERT(lower != NULL);
wdinfo("Unregistering: %s\n", upper->path);
#ifdef CONFIG_WATCHDOG_AUTOMONITOR
watchdog_automonitor_stop(upper);
#endif
/* Disable the watchdog timer */
DEBUGASSERT(lower->ops->stop); /* Required */
lower->ops->stop(lower);
/* Unregister the watchdog timer device */
unregister_driver(upper->path);
/* Then free all of the driver resources */
kmm_free(upper->path);
nxsem_destroy(&upper->exclsem);
kmm_free(upper);
}
#endif /* CONFIG_WATCHDOG */