On Fri, Nov 11, 2022 at 10:30 AM Jim Liu <jim.t90615@xxxxxxxxx> wrote: > -D_out: > the output data is the serial data needed to connect to hc595 and the > data will output to hc595 parallel pins. > you can use dts nout_gpios to create the number of pins. > > -D_in > this pin need to connect to hc165 and get the serial data from hc165. > you can use dts nin_gpios to create the number of pins. In the example it seems you enable d_out and d_in for *all* 64 pins, correct? So they are all either input or output. That in effect turns them into GPIOs, so I don't see the problem with simply always doing this? Just that things are configurable doesn't mean we always need to provide means to configure them. If you have a use case where the user wants to control this, then that is another thing. Otherwise just make all pins input and output and wait for a usecase that needs more control, maybe it will never appear. Yours, Linus Walleij
