[PATCH v2 11/12] drm/sun4i: backend: Make sure we don't have a commit pending

[Chen-Yu Tsai]

On Mon, Dec 18, 2017 at 10:57 PM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> If we try to read the backend registers while it fetches the new values, we
> end up with the value of some random register instead of the one we asked
> for.
>
> In order to prevent that, let's make sure that the very first thing we do
> during our atomic modesetting is to let the commit bit come to a rest.
>
> We don't have to worry about anything else since the only time we will
> trigger a new transaction is during the atomic_commit which comes much
> later.
>
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>

Reviewed-by: Chen-Yu Tsai <wens at csie.org>