On Fri, Dec 6, 2013 at 3:06 AM, Alexandre Courbot <acour...@nvidia.com> wrote:
> Some devices drivers make use of optional GPIO parameters. For such > drivers, it is important to discriminate between the case where no > GPIO mapping has been defined for the function they are requesting, and > the case where a mapping exists but an error occured while resolving it > or when acquiring the GPIO. > > This patch changes the family of gpiod_get() functions such that they > will return -ENOENT if and only if no GPIO mapping is defined for the > requested function. Other error codes are used when an actual error > occured during the GPIO resolution. > > Signed-off-by: Alexandre Courbot <acour...@nvidia.com> > --- > I think this change should be merged early as not having it may prevent > some users to switch to gpiod. I stumbled upon this issue while > considering porting a simple driver (pwm_bl) that has an optional GPIO > parameter. > > Mika, Andy: if Linus agrees with this change, could you take care of > having -ENOENT returned as well for the ACPI and SFI GPIOs lookup? > My understanding of ACPI was not sufficient to allow me to do it myself. > SFI OTOH should be trivial as it is a simple table. I'm aligned with this change, just waiting for a v2 with the fix requested by Andy to appear (maybe it's further up in the mail log I don't know...) Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
