incubator-nuttx/include/nuttx/sensors/mpu60x0.h

115 lines
3.8 KiB
C

/****************************************************************************
* include/nuttx/sensors/mpu60x0.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_MPU60X0_H
#define __INCLUDE_NUTTX_SENSORS_MPU60X0_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
/****************************************************************************
* Public Types
****************************************************************************/
/* These structures are defined elsewhere, and we don't need their
* definitions here.
*/
#ifdef CONFIG_MPU60X0_SPI
struct spi_dev_s;
#else
struct i2c_master_s;
#endif
/* Specifies the initial chip configuration and location.
*
* The chip supports both SPI and I2C interfaces, but you wouldn't use
* both at the same time on the same chip. It isn't an error to have
* one chip of each flavor in the system, though, so it's not an
* either-or configuration item.
*
* Important note :
*
* The driver determines which interface type to use according to
* which of the two groups of fields is non-NULL. Since support for
* I2C and SPI are individually configurable, however, users should
* let the compiler clear unused fields instead of setting unused
* fields to NULL directly. For example, if using SPI and a
* stack-allocated instance:
*
* struct mpu_config_s mpuc;
* memset(&mpuc, 0, sizeof(mpuc)); * sets i2c to NULL, if present *
* mpuc.spi = ...;
*
* Or, if using dynamic memory allocation and I2C:
*
* struct mpu_config_s* mpuc;
* mpuc = kmm_malloc(sizeof(*mpuc));
* memset(mpuc, 0, sizeof(*mpuc)); * sets spi to NULL, if present *
* mpuc.i2c = ...;
*
* The above examples will avoid compile-time errors unless the user
* forgets to enable their preferred interface type, and will allow
* them to disable or enable the unused interface type without
* changing their code.
*
*/
struct mpu_config_s
{
#ifdef CONFIG_MPU60X0_SPI
/* For users on SPI.
*
* spi_devid : the SPI master's slave-select number
* for the chip, as used in SPI_SELECT(..., dev_id, ...)
* spi : the SPI master device, as used in SPI_SELECT(spi, ..., ...)
*/
FAR struct spi_dev_s *spi;
int spi_devid;
#else
/* For users on I2C.
*
* i2c : the I2C master device
* addr : the I2C address.
*/
FAR struct i2c_master_s *i2c;
int addr;
#endif
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/* Declares the existence of an mpu60x0 chip, wired according to
* config; creates an interface to it at path.
*
* Returns 0 on success, or negative errno.
*/
int mpu60x0_register(FAR const char *path, FAR struct mpu_config_s *config);
#endif /* __INCLUDE_NUTTX_SENSORS_MPU60X0_H */