On Wed, 26 Feb 2025 at 14:47, Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > On Wed, Feb 26, 2025 at 03:37:47PM +0200, Andy Shevchenko wrote: > > On Tue, Feb 25, 2025 at 10:25:00PM +0100, Linus Walleij wrote: > > > On Mon, Feb 24, 2025 at 9:51 AM <brgl@xxxxxxxx> wrote: > > > > > > > In any case: Linus: what should be our policy here? There are some pinctrl > > > > drivers which return EINVAL if the pin in question is not in GPIO mode. I don't > > > > think this is an error. Returning errors should be reserved for read failures > > > > and so on. Are you fine with changing the logic here to explicitly default to > > > > INPUT as until recently all errors would be interpreted as such anyway? > > > > > > Oh hm I guess. There was no defined semantic until now anyway. Maybe > > > Andy has something to say about it though, it's very much his pin controller. > > > > Driver is doing correct things. If you want to be pedantic, we need to return > > all possible pin states (which are currently absent from GPIO get_direction() > > perspective) and even though it's not possible to tell from the pin muxer > > p.o.v. If function is I2C, it's open-drain, if some other, it may be completely > > different, but pin muxer might only guesstimate the state of the particular > > function is and I do not think guesstimation is a right approach. > > > > We may use the specific error code, though. and document that semantics. > > Brief looking at the error descriptions and the practical use the best (and > unique enough) choice may be EBADSLT. > In any case, I proposed to revert to the previous behavior in gpiochip_add_data() in my follow-up series so the issue should soon go away. Bart
