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So module parameter is used. >>>> >>>> But so what happens if user loads driver with default setting and >>>> then unloads driver and loads with a different setting as module >>>> option? >>>> >>>> Does this flow fall apart because the driver initially programmed 30ms? >>> >>> Reloading with new setting will overwrite the default setting. After the >>> module is loaded, it is not supposed to change before unloading the >>> module. >>> >> >> + Greg >> >> Greg, >> >> How do you feel about a module parameter for this purpose? Any other >> suggestions if you don't like it? > > module parameters should almost never never never be added to the > kernel, ESPECIALLY if it is for a device-specific thing (like in a > driver like this.) Please don't do that. > >> I was thinking a debugfs file still makes sense, but either the debugfs file >> can do unbind/rebind internally or user using debugfs file can do the >> unbind/bind sequence in sysfs after touching the debugfs file. > > debugfs is for debugging, don't require it for functionality that a > user/admin actually wants to do for a device as many distros and systems > disable it entirely due to all of the security holes it exposes to > admins. It was for tuning purposes. Max and team decided to make it a compile time macro. Any tuning can be done by developers recompiling.