octeon_i2c_reg_read
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL, NULL)
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA, error)
octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT, NULL)