From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Subject: Re: [RFC] libgpiod public API reviews needed
Date: Sun, 21 Jan 2018 23:18:59 +0100
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To: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Linus Walleij <linus.walleij@linaro.org>, linux-gpio@vger.kernel.org, Andy Shevchenko <andy.shevchenko@gmail.com>, Clemens Gruber <clemens.gruber@pqgruber.com>, Thierry Reding <thierry.reding@gmail.com>, Peter Rosin <peda@axentia.se>, Lars-Peter Clausen <lars@metafoo.de>

On Sun, Jan 21, 2018 at 10:30 PM, Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> 2018-01-21 16:49 GMT+01:00 Linus Walleij <linus.walleij@linaro.org>:
>> On Fri, Jan 19, 2018 at 2:28 PM, Bartosz Golaszewski <brgl@bgdev.pl> wrote:

> I was not aware of this, but it seems you're right! Nice catch, thanks.
>
> How about defining a local struct gpiod_timespec with both seconds and
> nanoseconds explicitly defined to uint64_t?

Where is that timestamp generated? Is this purely a user space interface
with the time read from gettimeofday(), or are we talking about  a new
kernel-to-user interface?

In a lot of cases, a simple 64-bit nanosecond counter using CLOCK_MONOTONIC
timestamps is the most robust and simple solution.

         Arnd