/* * Copyright 2018 Ettus Research, a National Instruments Company * * SPDX-License-Identifier: GPL-3.0-or-later */ #ifndef _I2CDEV_H_FOUND_ #define _I2CDEV_H_FOUND_ #ifdef __cplusplus extern "C" { #endif #include #include /* * This API provides access to i2c devices. It uses the character device API * from the Linux kernel and i2c-tools * * The kernel documentation can be found at * https://www.kernel.org/doc/Documentation/i2c/dev-interface */ /*! Initialize a i2cdev interface * * \param fd Return value of the file descriptor * \param device Path of i2cdev device, e.g. "/dev/i2c0" * \param timeout_ms Timeout to wait for ACK in ms * * \returns 0 if all is good, or an error code otherwise */ int i2cdev_open(int *fd, const char *device, const unsigned int timeout_ms); /*! Do an i2c transaction over i2cdev * If both tx and rx are to be done in one transaction, first tx data is * transmitted, followed by a repeated start condition, then the rx data is * read. * * \param fd File descriptor for the i2cdev bus segment * \param addr i2c device address * \param ten_bit_addr Nonzero if true (typically 0) * \param tx Buffer of data to be written to device * \param tx_len Total number of non-addr bytes to be written * \param rx Buffer where read data can be stored * \param rx_len Total number of bytes to be read * * Assumption: spidev was configured properly beforehand. * * \returns 0 if all is golden */ int i2cdev_transfer(int fd, uint16_t addr, int ten_bit_addr, uint8_t *tx, size_t tx_len, uint8_t *rx, size_t rx_len); #ifdef __cplusplus } #endif #endif /* _I2CDEV_H_FOUND_ */