/*
* 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
*/
long swI2CWriteReg(
unsigned char deviceAddress,
unsigned char registerIndex,
unsigned char data
)
{
long returnValue = 0;
/* Send the Start signal */
swI2CStart();
/* Send the device address and read the data. All should return success
in order for the writing processed to be successful
*/
if ((swI2CWriteByte(deviceAddress) != 0) ||
(swI2CWriteByte(registerIndex) != 0) ||
(swI2CWriteByte(data) != 0))
{
returnValue = -1;
}
/* Stop i2c and release the bus */
swI2CStop();
return returnValue;
}
/*
* 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 swI2CReadReg(
unsigned char deviceAddress,
unsigned char registerIndex
)
{
unsigned char data;
/* Send the Start signal */
swI2CStart();
/* Send the device address */
swI2CWriteByte(deviceAddress);
/* Send the register index */
swI2CWriteByte(registerIndex);
/* Get the bus again and get the data from the device read address */
swI2CStart();
swI2CWriteByte(deviceAddress + 1);
data = swI2CReadByte(1);
/* Stop swI2C and release the bus */
swI2CStop();
return data;
}
/*
* This function initializes GPIO port for SW I2C communication.
*
* Parameters:
* i2cClkGPIO - The GPIO pin to be used as i2c SCL
* i2cDataGPIO - The GPIO pin to be used as i2c SDA
*
* Return Value:
* -1 - Fail to initialize the i2c
* 0 - Success
*/
static long swI2CInit_SM750LE(unsigned char i2cClkGPIO,
unsigned char i2cDataGPIO)
{
int i;
/* Initialize the GPIO pin for the i2c Clock Register */
g_i2cClkGPIODataReg = GPIO_DATA_SM750LE;
g_i2cClkGPIODataDirReg = GPIO_DATA_DIRECTION_SM750LE;
/* Initialize the Clock GPIO Offset */
g_i2cClockGPIO = i2cClkGPIO;
/* Initialize the GPIO pin for the i2c Data Register */
g_i2cDataGPIODataReg = GPIO_DATA_SM750LE;
g_i2cDataGPIODataDirReg = GPIO_DATA_DIRECTION_SM750LE;
/* Initialize the Data GPIO Offset */
g_i2cDataGPIO = i2cDataGPIO;
/* Note that SM750LE don't have GPIO MUX and power is always on */
/* Clear the i2c lines. */
for(i=0; i<9; i++)
swI2CStop();
return 0;
}
/*******************************************************************************
swI2CInit
This function initializes the i2c attributes and bus
Parameters:
i2cClkGPIO - The GPIO pin to be used as i2c SCL
i2cDataGPIO - The GPIO pin to be used as i2c SDA
Return Value:
-1 - Fail to initialize the i2c
0 - Success
*******************************************************************************/
int32_t swI2CInit(unsigned char i2cClkGPIO, unsigned char i2cDataGPIO,swI2C_wait_proc function)
{
int i;
uint32_t value;
uint32_t gate;
/* Return 0 if the GPIO pins to be used is out of range. The range is only from [0..63] */
if ((i2cClkGPIO > 31) || (i2cDataGPIO > 31))
return (-1);
/* initialize the function pointer */
pfn_swI2C_wait = function;
if(pfn_swI2C_wait == NULL)
pfn_swI2C_wait = swI2CWait;
/* Initialize the GPIO pin for the i2c Clock Register */
g_i2cClkGPIOMuxReg = GPIO_MUX;
g_i2cClkGPIODataReg = GPIO_DATA;
g_i2cClkGPIODataDirReg = GPIO_DATA_DIRECTION;
/* Initialize the Clock GPIO Offset */
g_i2cClockGPIO = i2cClkGPIO;
/* Initialize the GPIO pin for the i2c Data Register */
g_i2cDataGPIOMuxReg = GPIO_MUX;
g_i2cDataGPIODataReg = GPIO_DATA;
g_i2cDataGPIODataDirReg = GPIO_DATA_DIRECTION;
/* Initialize the Data GPIO Offset */
g_i2cDataGPIO = i2cDataGPIO;
/* Enable the GPIO pins for the i2c Clock and Data (GPIO MUX) */
pokeRegisterDWord(g_i2cClkGPIOMuxReg,
peekRegisterDWord(g_i2cClkGPIOMuxReg) & ~(1 << g_i2cClockGPIO));
pokeRegisterDWord(g_i2cDataGPIOMuxReg,
peekRegisterDWord(g_i2cDataGPIOMuxReg) & ~(1 << g_i2cDataGPIO));
/* Enable GPIO power */
enableGPIO(1);
/* Clear the i2c lines. */
for(i=0; i<9; i++)
swI2CStop();
return 0;
}
/*
* This function initializes the i2c attributes and bus
*
* Parameters:
* i2cClkGPIO - The GPIO pin to be used as i2c SCL
* i2cDataGPIO - The GPIO pin to be used as i2c SDA
*
* Return Value:
* -1 - Fail to initialize the i2c
* 0 - Success
*/
long swI2CInit(
unsigned char i2cClkGPIO,
unsigned char i2cDataGPIO
)
{
int i;
/* Return 0 if the GPIO pins to be used is out of range. The range is only from [0..63] */
if ((i2cClkGPIO > 31) || (i2cDataGPIO > 31))
return -1;
if (getChipType() == SM750LE)
return swI2CInit_SM750LE(i2cClkGPIO, i2cDataGPIO);
/* Initialize the GPIO pin for the i2c Clock Register */
g_i2cClkGPIOMuxReg = GPIO_MUX;
g_i2cClkGPIODataReg = GPIO_DATA;
g_i2cClkGPIODataDirReg = GPIO_DATA_DIRECTION;
/* Initialize the Clock GPIO Offset */
g_i2cClockGPIO = i2cClkGPIO;
/* Initialize the GPIO pin for the i2c Data Register */
g_i2cDataGPIOMuxReg = GPIO_MUX;
g_i2cDataGPIODataReg = GPIO_DATA;
g_i2cDataGPIODataDirReg = GPIO_DATA_DIRECTION;
/* Initialize the Data GPIO Offset */
g_i2cDataGPIO = i2cDataGPIO;
/* Enable the GPIO pins for the i2c Clock and Data (GPIO MUX) */
POKE32(g_i2cClkGPIOMuxReg,
PEEK32(g_i2cClkGPIOMuxReg) & ~(1 << g_i2cClockGPIO));
POKE32(g_i2cDataGPIOMuxReg,
PEEK32(g_i2cDataGPIOMuxReg) & ~(1 << g_i2cDataGPIO));
/* Enable GPIO power */
enableGPIO(1);
/* Clear the i2c lines. */
for(i=0; i<9; i++)
swI2CStop();
return 0;
}
