On Mon, Dec 7, 2020 at 4:48 PM Johan Hovold <johan@xxxxxxxxxx> wrote: > On Mon, Dec 07, 2020 at 03:34:23PM +0000, Marc Zyngier wrote: > > If they claim that their lines are available, and then refuse to > > let the user play with it, that's just a bug willing to be fixed. > > My point was that this is how *all* gpio drivers work, and that muxing > is somewhat orthogonal to the gpio controller implementation. This is true. It's because it is orthogonal that the separate subsystem for pin control including pin muxing exists. Should I be really overly picky, the drivers that can mux lines like this should be implementing the pin control mux driver side as well just to make Linux aware of this. But if the muxing cannot be changed by the kernel (albeit with special tools) then it would be pretty overengineered for this case. Things would be much easier if this wasn't some flashing configuration but more of a runtime thing (which is kind of the implicit assumption in pin control land). We don't really have many drivers that are "muxable by (intrusive) flashing" as opposed to "muxable by setting some bits" so in that way these FTDI drivers and siblings are special. So this needs some special considerations to become user friendly I think. Yours, Linus Walleij
