/************************************************************************************
* arch/arm/src/stm32/stm32_qencoder.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 <stdint.h>
#include <errno.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include <nuttx/sensors/qencoder.h>
#include "up_arch.h"
#include "stm32_qencoder.h"
#ifdef CONFIG_QENCODER
/************************************************************************************
* Private Types
************************************************************************************/
struct stm32_lowerhalf_s
{
/* The first field of this state structure must be a pointer to the lower-
* half callback structure:
*/
FAR const struct qe_ops_s *ops; /* Lower half callback structure */
/* STM32 driver-specific fields: */
};
/************************************************************************************
* Private Function Prototypes
************************************************************************************/
/* Lower-half Quadrature Encoder Driver Methods */
static int stm32_setup(FAR struct qe_lowerhalf_s *lower);
static int stm32_shutdown(FAR struct qe_lowerhalf_s *lower);
static int stm32_position(FAR struct qe_lowerhalf_s *lower, int32_t *pos);
static int stm32_reset(FAR struct qe_lowerhalf_s *lower);
static int stm32_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd, unsigned long arg);
/************************************************************************************
* Private Data
************************************************************************************/
/* The lower half callback structure */
FAR const struct qe_ops_s g_qecallbacks =
{
.setup = stm32_setup,
.shutdown = stm32_shutdown,
.position = stm32_position,
.reset = stm32_reset,
.ioctl = stm32_ioctl,
};
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: stm32_setup
*
* Description:
* This method is called when the driver is opened. The lower half driver
* should configure and initialize the device so that it is ready for use.
* The initial position value should be zero. *
*
************************************************************************************/
static int stm32_setup(FAR struct qe_lowerhalf_s *lower)
{
#warning "Missing logic"
return -ENOSYS;
}
/************************************************************************************
* Name: stm32_shutdown
*
* Description:
* This method is called when the driver is closed. The lower half driver
* should stop data collection, free any resources, disable timer hardware, and
* put the system into the lowest possible power usage state *
*
************************************************************************************/
static int stm32_shutdown(FAR struct qe_lowerhalf_s *lower)
{
#warning "Missing logic"
return -ENOSYS;
}
/************************************************************************************
* Name: stm32_position
*
* Description:
* Return the current position measurement.
*
************************************************************************************/
static int stm32_position(FAR struct qe_lowerhalf_s *lower, int32_t *pos)
{
#warning "Missing logic"
return -ENOSYS;
}
/************************************************************************************
* Name: stm32_reset
*
* Description:
* Reset the position measurement to zero.
*
************************************************************************************/
static int stm32_reset(FAR struct qe_lowerhalf_s *lower)
{
#warning "Missing logic"
return -ENOSYS;
}
/************************************************************************************
* Name: stm32_ioctl
*
* Description:
* Lower-half logic may support platform-specific ioctl commands
*
************************************************************************************/
static int stm32_ioctl(FAR struct qe_lowerhalf_s *lower, int cmd, unsigned long arg)
{
/* No ioctl commands supported */
return -ENOTTY;
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: stm32_qeinitialize
*
* Description:
* Initialize a quadrature encoder interface. This function must be called from
* board-specific logic after input pins have been configured.
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/qe0"
*
* Returned Values:
* Zero on success; A negated errno value is returned on failure.
*
************************************************************************************/
int stm32_qeinitialize(FAR const char *devpath)
{
FAR struct stm32_lowerhalf_s *lower;
int ret;
/* Allocate an instance to the device-specific, lower-half state structure */
lower = (FAR struct stm32_lowerhalf_s *)kmalloc(sizeof(struct stm32_lowerhalf_s));
if (lower)
{
return -ENOMEM;
}
/* Initialize the allocated state structure */
lower->ops = &g_qecallbacks;
/* Register the lower-half driver */
ret = qe_register(devpath, (FAR struct qe_lowerhalf_s *)lower);
if (ret < 0)
{
kfree(lower);
return ret;
}
return OK;
}
#endif /* CONFIG_QENCODER */
