linux/drivers/staging/sm750fb/ddk750_hwi2c.c

// SPDX-License-Identifier: GPL-2.0
#define USE_HW_I2C
#ifdef USE_HW_I2C
#include "ddk750_chip.h"
#include "ddk750_reg.h"
#include "ddk750_hwi2c.h"
#include "ddk750_power.h"

#define MAX_HWI2C_FIFO …
#define HWI2C_WAIT_TIMEOUT …

int sm750_hw_i2c_init(unsigned char bus_speed_mode)
{ … }

void sm750_hw_i2c_close(void)
{ … }

static long hw_i2c_wait_tx_done(void)
{ … }

/*
 *  This function writes data to the i2c slave device registers.
 *
 *  Parameters:
 *      addr            - i2c Slave device address
 *      length          - Total number of bytes to be written to the device
 *      buf             - The buffer that contains the data to be written to the
 *                     i2c device.
 *
 *  Return Value:
 *      Total number of bytes those are actually written.
 */
static unsigned int hw_i2c_write_data(unsigned char addr,
				      unsigned int length,
				      unsigned char *buf)
{ … }

/*
 *  This function reads data from the slave device and stores them
 *  in the given buffer
 *
 *  Parameters:
 *      addr            - i2c Slave device address
 *      length          - Total number of bytes to be read
 *      buf             - Pointer to a buffer to be filled with the data read
 *                     from the slave device. It has to be the same size as the
 *                     length to make sure that it can keep all the data read.
 *
 *  Return Value:
 *      Total number of actual bytes read from the slave device
 */
static unsigned int hw_i2c_read_data(unsigned char addr,
				     unsigned int length,
				     unsigned char *buf)
{ … }

/*
 *  This function reads the slave device's register
 *
 *  Parameters:
 *      deviceAddress   - i2c Slave device address which register
 *                        to be read from
 *      registerIndex   - Slave device's register to be read
 *
 *  Return Value:
 *      Register value
 */
unsigned char sm750_hw_i2c_read_reg(unsigned char addr, unsigned char reg)
{ … }

/*
 *  This function writes a value to the slave device's register
 *
 *  Parameters:
 *      deviceAddress   - i2c Slave device address which register
 *                        to be written
 *      registerIndex   - Slave device's register to be written
 *      data            - Data to be written to the register
 *
 *  Result:
 *          0   - Success
 *         -1   - Fail
 */
int sm750_hw_i2c_write_reg(unsigned char addr,
			   unsigned char reg,
			   unsigned char data)
{ … }

#endif