In the MAX9275 and other Maxim SerDes products, dual function pins are read on power up and then reprogrammed to their operating function. For example, the GPO pin on some devices is read as HIM on power up to set this mode and then reprogrammed as an output.
Maxim datasheets recommend 30kohm pull up on these pins if the mode (such as HIM) needs to be set high ("1"). This resistor is sufficient to ensure a "1" is correctly read in all cases where there is no other external circuitry connected to the pin. External circuitry can pull the pin low and cause it to be read incorrectly. In cases where external circuitry is connected to these pins, a better choice for pull up resistor is 4.7kohm to allow for small leakage in the circuitry. An analysis to ensure the pin is not pulled low ("0") is recommended.