incubator-nuttx/include/nuttx/sensors/zerocross.h

130 lines
4.5 KiB
C

/****************************************************************************
* include/nuttx/zerocross.h
*
* 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_SENSORS_ZEROCROSS_H
#define __INCLUDE_NUTTX_SENSORS_ZEROCROSS_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/fs/ioctl.h>
#include <signal.h>
#ifdef CONFIG_SENSORS_ZEROCROSS
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************
* CONFIG_SENSORS_ZEROCROSS - Enables support for the zero cross AC detection
* upper half
*/
/* Command: ZCIOC_REGISTER
* Description: Register to receive a signal whenever there is zero cross
* interrupt event.
* Argument: A read-only pointer to an instance of struct sigevent
* Return: Zero (OK) on success. Minus one will be returned on failure
* with the errno value set appropriately.
*/
#define ZCIOC_REGISTER _ZCIOC(0x0001)
/****************************************************************************
* Public Types
****************************************************************************/
/* This is the vtable that is used to by the upper half of the zero cross
* to call back into the lower half of the zero cross driver.
*/
struct zc_lowerhalf_s;
/* This is the type of the discrete zero cross interrupt handler used with
* the struct zc_lowerhalf_s enable() method.
*/
typedef CODE void (*zc_interrupt_t)
(FAR const struct zc_lowerhalf_s *lower, FAR void *arg);
/* This is the interface between the lower half zero cross detection driver
* and the upper half zero cross detection driver. A (device-specific)
* instance of this structure is passed to the upper-half driver when the
* zero cross driver is registered.
*
* Normally that lower half logic will have its own, custom state structure
* that is simply cast to struct zc_lowerhalf_s. In order to perform such
* casts, the initial fields of the custom state structure match the initial
* fields of the following generic lower half state structure.
*/
struct zc_lowerhalf_s
{
/* Enable interrupt on the defined pin used to zero cross detection */
CODE void (*zc_enable)(FAR const struct zc_lowerhalf_s *lower,
zc_interrupt_t handler, FAR void *arg);
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: zc_register
*
* Description:
* Register the Zero Cross lower half device as 'devpath'
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/zc0"
* lower - An instance of the lower half interface
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int zc_register(FAR const char *devpath, FAR struct zc_lowerhalf_s *lower);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_SENSORS_ZEROCROSS */
#endif /* __INCLUDE_NUTTX_SENSORS_ZEROCROSS_H */