Multifunction device with register space for individually enabling or disabling a function of plurality of functions in response to function configuration

A computer system comprising:

• at least one system processor;
• a computer bus, the at least one system processor operably coupled to the computer bus;
• a multifunction device operably coupled to the computer bus, the multifunction device including a plurality of functions, the multifunction device including a register space including a predefined header region and a device dependent region, the predefined header region including fields that uniquely identify a function of the functions and allow the function to be generically controlled, the device dependent region including an enable/disable byte register;
• and
• a memory for storing code whose execution writes an indication to a location in the register space to enable or disable a function of the plurality of functions in response to a function configuration.

A method for disabling a function of a multifunction device operably coupled to a computer bus comprising:

• writing to a location in a register space of the multifunction device an indication to enable or disable a function in response to a function configuration, the register space including a predefined header region and a device dependent region, the predefined header region including fields that uniquely identify the function and allow the function to be generically controlled, the device dependent region including an enable/disable byte register;
• generating a bus command on the computer bus addressed to the function;
• and
• reading the indication in the location in the register space wherein the function is not responsive to the generated command in response to the reading that the function is disabled.

A computer system comprising:

• at least one system processor;
• a computer bus, the at least one system processor operably coupled to the computer bus;
• a multifunction device located on the computer bus, the multifunction device including a plurality of functions, the multifunction device includes a register space, the multifunction device including a first circuit, wherein in response to a bus command addressed to a function of the multifunction device, the first circuit reads a location in the register space of the multifunction device to determine whether the function is configured as enabled or disabled and if enabled, then to be responsive to the bus command and if disabled, then to be non-responsive to the bus command;
• and
• the register space including a predefined header region and a device dependent region, the predefined header region including fields that uniquely identify the function and allow the function to be generically controlled, the device dependent region including an enable/disable byte register.