/*
* This function reads one byte from the slave device
*
* Parameters:
* ack - Flag to indicate either to send the acknowledge
* message to the slave device or not
*
* Return Value:
* One byte data read from the Slave device
*/
static unsigned char sw_i2c_read_byte(unsigned char ack)
{
int i;
unsigned char data = 0;
for (i = 7; i >= 0; i--) {
/* Set the SCL to Low and SDA to High (Input) */
sw_i2c_scl(0);
sw_i2c_sda(1);
sw_i2c_wait();
/* Set the SCL High */
sw_i2c_scl(1);
sw_i2c_wait();
/* Read data bits from SDA */
data |= (sw_i2c_read_sda() << i);
}
if (ack)
sw_i2c_ack();
/* Set the SCL Low and SDA High */
sw_i2c_scl(0);
sw_i2c_sda(1);
return data;
}
int sw_i2c_read(unsigned char chip, unsigned char location, unsigned char* buf, int count)
{
int i;
#ifdef MROBE_100 /* does not use register addressing */
(void) location;
#else
sw_i2c_start();
sw_i2c_outb((chip & 0xfe) | SW_I2C_WRITE);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -1;
}
sw_i2c_outb(location);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -2;
}
#endif
sw_i2c_start();
sw_i2c_outb((chip & 0xfe) | SW_I2C_READ);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -3;
}
for (i=0; i<count-1; i++)
{
buf[i] = sw_i2c_inb();
sw_i2c_ack();
}
/* 1byte min */
buf[i] = sw_i2c_inb();
sw_i2c_nack();
sw_i2c_stop();
return 0;
}
