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From:   Bartosz Golaszewski <bgolaszewski@baylibre.com>
Date:   Tue, 4 Aug 2020 19:47:43 +0200
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Subject: Re: [PATCH v2 05/18] gpiolib: cdev: support GPIO_GET_LINE_IOCTL and GPIOLINE_GET_VALUES_IOCTL
To:     Kent Gibson <warthog618@gmail.com>
Cc:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>
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On Tue, Aug 4, 2020 at 1:01 AM Kent Gibson <warthog618@gmail.com> wrote:
>

[snip]

>
> > Also: I just started going through the patches - nice idea with the
> > GPIO attributes, I really like it. Although I need to give it a longer
> > thought tomorrow - I'm wondering if we can maybe unify them and the
> > flags.
> >
>
> I had an earlier draft that did just that - and that is partially why
> the loop is last in wins - I was using slot 0 as the default flags.
> But the default flags cover a lot of use cases, including all of v1, and
> it was simple and cheap to provide a default - and it simplified the
> initial port of libgpiod to v2...
>

If porting libgpiod to v2 is the only concern then I wouldn't stress
about it. At the same time I'm wondering - is there any use-case where
we wouldn't need the flags attribute for at least some lines? Because
if it's always required than maybe having a default isn't that bad.

Bartosz