Re: Fw: [3.18.3] poll() on gpio pins broken

[Alexandre Courbot <gnurou@gmail.com>]

On Tue, Mar 3, 2015 at 7:31 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
> On Tue, Mar 3, 2015 at 9:27 AM, Alexandre Courbot <gnurou@gmail.com> wrote:
>
>> It really comes down to how user-space wants to access GPIOs. I
>> suspect the majority of sysfs accesses is done by scripts and other
>> simple programs. If we introduce a char device that takes requires
>> ioctls, it is then customary to add a small user-space library to
>> abstract that (for both convenience and safety - think libdrm). Do we
>> want to maintain libgpio?
>
> Good point.
>
> We have no clue about how the majority out there use the GPIO
> sysfs, but I have heard of mission-critical systems just hammering
> GPIOs from userspace.
>
> Sadly many of these industrial users are "I just want it to work, now"
> types and they don't step forward much on these mailing lists.
> (Learned from private conversations...)
>
> Maybe if noone voice their opinion and offer to help with this, we can
> assume they don't exist (well obviously a community does not exist)
> and their specific needs be ignored until they put their money where
> their mouth is.

That's the only way we can handle the situation if people don't
manifest their needs. But does this mean that you would agree with a
cleaner, multi-GPIO friendly sysfs-based solution, or I am
misunderstanding you?