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/*
// Copyright (c) 2019 Intel Corporation
//
// 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.
*/
#pragma once
#include <errno.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <experimental/filesystem>
#include <phosphor-logging/log.hpp>
extern "C" {
#include <i2c/smbus.h>
#include <linux/i2c-dev.h>
}
namespace intel
{
namespace pfr
{
/** @class I2CFile
* @brief Responsible for handling file pointer
*/
class I2CFile
{
private:
/** @brief handler for operating on file */
int fd;
public:
I2CFile() = delete;
I2CFile(const I2CFile&) = delete;
I2CFile& operator=(const I2CFile&) = delete;
I2CFile(I2CFile&&) = delete;
I2CFile& operator=(I2CFile&&) = delete;
/** @brief Opens i2c device file and sets slave
*
* @param[in] i2cBus - I2C bus number
* @param[in] slaveAddr - I2C slave address
* @param[in] flags - Flags
*/
I2CFile(const int& i2cBus, const int& slaveAddr, const int& flags)
{
std::string i2cDev = "/dev/i2c-" + std::to_string(i2cBus);
fd = open(i2cDev.c_str(), flags);
if (fd < 0)
{
throw std::runtime_error("Unable to open i2c device.");
}
if (ioctl(fd, I2C_SLAVE_FORCE, slaveAddr) < 0)
{
close(fd);
fd = -1;
throw std::runtime_error("Unable to set i2c slave address.");
}
}
/** @brief Reads the byte data from I2C dev
*
* @param[in] Offset - Offset value
* @param[out] byte data - Offset value
*/
uint8_t i2cReadByteData(const uint8_t& offset)
{
uint8_t value = i2c_smbus_read_byte_data(fd, offset);
if (value < 0)
{
throw std::runtime_error("i2c_smbus_read_byte_data() failed");
}
return value;
}
/** @brief Writes the byte data to I2C dev
*
* @param[in] Offset - Offset value
* @param[in] Byte data - Data
*/
void i2cWriteByteData(const uint8_t offset, const uint8_t value)
{
int retries = 3;
while (i2c_smbus_write_byte_data(fd, offset, value) < 0)
{
if (!retries--)
{
throw std::runtime_error("i2c_smbus_write_byte_data() failed");
}
std::this_thread::sleep_for(std::chrono::milliseconds(10));
}
return;
}
~I2CFile()
{
if (!(fd < 0))
{
close(fd);
}
}
auto operator()()
{
return fd;
}
};
} // namespace pfr
} // namespace intel
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