GL520_REG_FAN_DIV
val = gl520_read_value(client, GL520_REG_FAN_DIV);
gl520_write_value(client, GL520_REG_FAN_DIV,
(gl520_read_value(client, GL520_REG_FAN_DIV)
gl520_write_value(client, GL520_REG_FAN_DIV,
(gl520_read_value(client, GL520_REG_FAN_DIV)
#define GL520_REG_FAN_OFF GL520_REG_FAN_DIV