/****************************************************************************
* arch/arm/src/stm32/stm32_wwdg.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <nuttx/arch.h>
#include <stdint.h>
#include <errno.h>
#include <nuttx/watchdog.h>
#include "up_arch.h"
#include "stm32_wdg.h"
#if defined(CONFIG_WATCHDOG) && defined(CONFIG_STM32_WWDG)
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure provides the private representation of the "lower-half"
* driver state structure. This structure must be cast-compatible with the
* well-known watchdog_lowerhalf_s structure.
*/
struct stm32_lowerhalf_s
{
FAR const struct watchdog_ops_s *ops; /* Lower half operations */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Register operations ******************************************************/
#if defined(CONFIG_STM32_WWDG_REGDEBUG) && defined(CONFIG_DEBUG)
static uint32_t stm32_getreg(uint32_t addr);
static void stm32_putreg(uint32_t val, uint32_t addr);
#else
# define stm32_getreg(addr) getreg32(addr)
# define stm32_putreg(val,addr) putreg32(val,addr)
#endif
/* "Lower half" driver methods **********************************************/
static int stm32_start(FAR struct watchdog_lowerhalf_s *lower);
static int stm32_stop(FAR struct watchdog_lowerhalf_s *lower);
static int stm32_keepalive(FAR struct watchdog_lowerhalf_s *lower);
static int stm32_getstatus(FAR struct watchdog_lowerhalf_s *lower,
FAR struct watchdog_status_s *status);
static int stm32_settimeout(FAR struct watchdog_lowerhalf_s *lower,
uint32_t timeout);
static xcpt_t stm32_capture(FAR struct watchdog_lowerhalf_s *lower,
xcpt_t handler);
static int stm32_ioctl(FAR struct watchdog_lowerhalf_s *lower, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
/* "Lower half" driver methods */
static const struct watchdog_ops_s g_wdgops =
{
.start = stm32_start,
.stop = stm32_stop,
.keepalive = stm32_keepalive,
.getstatus = stm32_getstatus,
.settimeout = stm32_settimeout,
.capture = stm32_capture,
.ioctl = stm32_ioctl,
};
/* "Lower half" driver state */
static struct stm32_lowerhalf_s g_wdgdev;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: stm32_getreg
*
* Description:
* Get the contents of an STM32 register
*
****************************************************************************/
#if defined(CONFIG_STM32_WWDG_REGDEBUG) && defined(CONFIG_DEBUG)
static uint32_t stm32_getreg(uint32_t addr)
{
static uint32_t prevaddr = 0;
static uint32_t preval = 0;
static uint32_t count = 0;
/* Read the value from the register */
uint32_t val = getreg32(addr);
/* Is this the same value that we read from the same registe last time? Are
* we polling the register? If so, suppress some of the output.
*/
if (addr == prevaddr && val == preval)
{
if (count == 0xffffffff || ++count > 3)
{
if (count == 4)
{
lldbg("...\n");
}
return val;
}
}
/* No this is a new address or value */
else
{
/* Did we print "..." for the previous value? */
if (count > 3)
{
/* Yes.. then show how many times the value repeated */
lldbg("[repeats %d more times]\n", count-3);
}
/* Save the new address, value, and count */
prevaddr = addr;
preval = val;
count = 1;
}
/* Show the register value read */
lldbg("%08x->%08x\n", addr, val);
return val;
}
#endif
/****************************************************************************
* Name: stm32_putreg
*
* Description:
* Set the contents of an STM32 register to a value
*
****************************************************************************/
#if defined(CONFIG_STM32_WWDG_REGDEBUG) && defined(CONFIG_DEBUG)
static void stm32_putreg(uint32_t val, uint32_t addr)
{
/* Show the register value being written */
lldbg("%08x<-%08x\n", addr, val);
/* Write the value */
putreg32(val, addr);
}
#endif
/****************************************************************************
* Name: stm32_start
*
* Description:
* Start the watchdog timer, resetting the time to the current timeout,
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_start(FAR struct watchdog_lowerhalf_s *lower)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: stm32_stop
*
* Description:
* Stop the watchdog timer
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_stop(FAR struct watchdog_lowerhalf_s *lower)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: stm32_keepalive
*
* Description:
* Reset the watchdog timer to the current timeout value, prevent any
* imminent watchdog timeouts. This is sometimes referred as "pinging"
* the atchdog timer or "petting the dog".
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_keepalive(FAR struct watchdog_lowerhalf_s *lower)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: stm32_getstatus
*
* Description:
* Get the current watchdog timer status
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
* stawtus - The location to return the watchdog status information.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_getstatus(FAR struct watchdog_lowerhalf_s *lower,
FAR struct watchdog_status_s *status)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: stm32_settimeout
*
* Description:
* Set a new timeout value (and reset the watchdog timer)
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
* timeout - The new timeout value in millisecnds.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_settimeout(FAR struct watchdog_lowerhalf_s *lower,
uint32_t timeout)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Name: stm32_capture
*
* Description:
* Don't reset on watchdog timer timeout; instead, call this user provider
* timeout handler. NOTE: Providing handler==NULL will restore the reset
* behavior.
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
* newhandler - The new watchdog expiration function pointer. If this
* function pointer is NULL, then the the reset-on-expiration
* behavior is restored,
*
* Returned Values:
* The previous watchdog expiration function pointer or NULL is there was
* no previous function pointer, i.e., if the previous behavior was
* reset-on-expiration (NULL is also returned if an error occurs).
*
****************************************************************************/
static xcpt_t stm32_capture(FAR struct watchdog_lowerhalf_s *lower,
xcpt_t handler)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return NULL;
}
/****************************************************************************
* Name: stm32_ioctl
*
* Description:
* Any ioctl commands that are not recognized by the "upper-half" driver
* are forwarded to the lower half driver through this method.
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower
* driver state structure.
* cmd - The ioctol command value
* arg - The optional argument that accompanies the 'cmd'. The
* interpretation of this argument depends on the particular
* command.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int stm32_ioctl(FAR struct watchdog_lowerhalf_s *lower, int cmd,
unsigned long arg)
{
FAR struct stm32_lowerhalf_s *priv = (FAR struct stm32_lowerhalf_s *)lower;
DEBUGASSERT(priv);
#warning "Missing logic"
return -ENOSYS;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stm32_wwdginitialize
*
* Description:
* Initialize the WWDG watchdog time. The watchdog timer is intialized and
* registers as 'devpath. The initial state of the watchdog time is
* disabled.
*
* Input Parameters:
* devpath - The full path to the watchdog. This should be of the form
* /dev/watchdog0
*
* Returned Values:
* None
*
****************************************************************************/
void stm32_wwdginitialize(FAR const char *devpath)
{
FAR struct stm32_lowerhalf_s *priv = &g_wdgdev;
/* Initialize the driver state structure. Here we assume: (1) the state
* structure lies in .bss and was zeroed at reset time. This function is
* only called once so it is never necessary to re-zero the structure.
*/
priv->ops = &g_wdgops;
/* Register the watchdog driver as /dev/watchdog0 */
(void)watchdog_register(devpath, (FAR struct watchdog_lowerhalf_s *)priv);
}
#endif /* CONFIG_WATCHDOG && CONFIG_STM32_WWDG */
