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Date:   Wed, 7 Dec 2022 11:55:50 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Kent Gibson <warthog618@gmail.com>, Marc Zyngier <maz@kernel.org>,
        linux-gpio@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, Bartosz Golaszewski <brgl@bgdev.pl>,
        Jonathan Corbet <corbet@lwn.net>,
        Hans de Goede <hdegoede@redhat.com>
Subject: Re: [PATCH v1 2/3] Documentation: gpio: Add a section on what to
 return in ->get() callback
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On Wed, Dec 07, 2022 at 01:06:46AM +0100, Linus Walleij wrote:
> On Mon, Dec 5, 2022 at 2:43 AM Kent Gibson <warthog618@gmail.com> wrote:
> 
> > My preference would be for the driver API to be extended with a new
> > callback for the output buffer, say get_output(), and have the existing
> > get() always return the input buffer.
> 
> This has a certain elegance to it, as it cuts to the bone of the
> problem and partition it in two halves, reflecting the two pieces
> of hardware: input and output buffer. Also follows Rusty Russells
> API hierarchy.

The (one of) problem is that not all hardware may support input and output
be enabled at the same time. What would that new API return in that case
and how it would be better with get() returning the value depending on
direction?

-- 
With Best Regards,
Andy Shevchenko