incubator-nuttx/include/nuttx/rf/dat-31r5-sp.h

82 lines
2.9 KiB
C

/****************************************************************************
* include/nuttx/rf/dat-31r5-sp.h
* Character driver for the Mini-Circuits DAT-31R5-SP+ digital step
* attenuator.
*
* Licensed 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_RF_DAT_31R5_SP_H
#define __INCLUDE_NUTTX_RF_DAT_31R5_SP_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/irq.h>
#include <nuttx/config.h>
#include <nuttx/rf/ioctl.h>
#include <nuttx/spi/spi.h>
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: dat31r5sp_register
*
* Description:
* Register the dat31r5sp character device as 'devpath'. WARNING:
* the DAT-31R5-SP+ is not spi compatible because it hasn't a proper
* chip-select input, but it can coexist with other devices on the
* spi bus assuming that the LE (Latch Enable) is always 0 when the
* device isn't selected. With LE=0 the internal shift-register will
* store the last 6 bits sent through the bus, but it will only
* change the attenuation level when LE=1. This driver sends the
* attenuation bitstream and gives a small positive pulse to LE.
*
* Remember when implementing the corresponding spi select function
* when selected == true LE should be 1, and when selected == false
* LE should be 0.
*
* Input Parameters:
* devpath - The full path to the driver to register. E.g., "/dev/att0"
* spi - An instance of the SPI interface to use to communicate with
* spidev - Number of the spi device (used to drive the Latch Enable pin).
*
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int dat31r5sp_register(FAR const char *devpath,
FAR struct spi_dev_s *spi,
int spidev);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_RF_DAT_31R5_SP_H */