W83792D_REG_FAN_CFG
reg_tmp = w83792d_read_value(client, W83792D_REG_FAN_CFG);
cfg4_tmp = w83792d_read_value(client, W83792D_REG_FAN_CFG) & 0xc0;
w83792d_write_value(client, W83792D_REG_FAN_CFG, fan_cfg_tmp);