static int
i2c_start(device_t dev, u_char slave, int timeout)
{
struct i2c_softc *sc;
int error;
sc = device_get_softc(dev);
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN);
DELAY(10); /* Delay for controller to sample bus state. */
if (i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB) {
return (i2c_error_handler(sc, IIC_EBUSERR));
}
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN | I2CCR_MSTA | I2CCR_MTX);
if ((error = wait_for_busbusy(sc, true)) != IIC_NOERR)
return (i2c_error_handler(sc, error));
i2c_write_reg(sc, I2C_STATUS_REG, 0);
i2c_write_reg(sc, I2C_DATA_REG, slave);
error = wait_for_xfer(sc, true);
return (i2c_error_handler(sc, error));
}
static int
i2c_read(device_t dev, char *buf, int len, int *read, int last, int delay)
{
struct i2c_softc *sc;
int error, reg;
sc = device_get_softc(dev);
*read = 0;
if (len) {
if (len == 1)
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN |
I2CCR_MSTA | I2CCR_TXAK);
else
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN |
I2CCR_MSTA);
/* Dummy read to prime the receiver. */
i2c_write_reg(sc, I2C_STATUS_REG, 0x0);
i2c_read_reg(sc, I2C_DATA_REG);
}
error = 0;
*read = 0;
while (*read < len) {
if ((error = wait_for_xfer(sc, false)) != IIC_NOERR)
break;
i2c_write_reg(sc, I2C_STATUS_REG, 0x0);
if (last) {
if (*read == len - 2) {
/* NO ACK on last byte */
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN |
I2CCR_MSTA | I2CCR_TXAK);
} else if (*read == len - 1) {
/* Transfer done, signal stop. */
i2c_write_reg(sc, I2C_CONTROL_REG, I2CCR_MEN |
I2CCR_TXAK);
wait_for_busbusy(sc, false);
}
}
reg = i2c_read_reg(sc, I2C_DATA_REG);
*buf++ = reg;
(*read)++;
}
return (i2c_error_handler(sc, error));
}
static int
i2c_write(device_t dev, const char *buf, int len, int *sent, int timeout)
{
struct i2c_softc *sc;
int error;
sc = device_get_softc(dev);
error = 0;
*sent = 0;
while (*sent < len) {
i2c_write_reg(sc, I2C_STATUS_REG, 0x0);
i2c_write_reg(sc, I2C_DATA_REG, *buf++);
if ((error = wait_for_xfer(sc, true)) != IIC_NOERR)
break;
(*sent)++;
}
return (i2c_error_handler(sc, error));
}
static int
i2c_repeated_start(device_t dev, u_char slave, int timeout)
{
struct i2c_softc *sc;
int error;
sc = device_get_softc(dev);
if ((i2c_read_reg(sc, I2C_STATUS_REG) & I2CSR_MBB) == 0) {
return (IIC_EBUSERR);
}
/*
* Set repeated start condition, delay (per reference manual, min 156nS)
* before writing slave address, wait for ack after write.
*/
i2c_flag_set(sc, I2C_CONTROL_REG, I2CCR_RSTA);
DELAY(1);
i2c_write_reg(sc, I2C_STATUS_REG, 0x0);
i2c_write_reg(sc, I2C_DATA_REG, slave);
error = wait_for_xfer(sc, true);
return (i2c_error_handler(sc, error));
}
void i2c2_error_interrupt(void) { i2c_error_handler(I2C2); }