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Date:   Fri, 14 Jan 2022 18:06:55 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Simon Ser <contact@emersion.fr>
Cc:     Tomohito Esaki <etom@igel.co.jp>, dri-devel@lists.freedesktop.org,
        Alex Deucher <alexander.deucher@amd.com>,
        Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>,
        "Pan, Xinhui" <Xinhui.Pan@amd.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Ben Skeggs <bskeggs@redhat.com>,
        Michel =?iso-8859-1?Q?D=E4nzer?= <mdaenzer@redhat.com>,
        Qingqing Zhuo <qingqing.zhuo@amd.com>,
        Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>,
        Mark Yacoub <markyacoub@chromium.org>,
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        Evan Quan <evan.quan@amd.com>, Petr Mladek <pmladek@suse.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Lee Jones <lee.jones@linaro.org>,
        Abhinav Kumar <abhinavk@codeaurora.org>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Rob Clark <robdclark@chromium.org>,
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        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Damian Hobson-Garcia <dhobsong@igel.co.jp>,
        Takanari Hayama <taki@igel.co.jp>
Subject: Re: [RFC PATCH v3 2/3] drm: add support modifiers for drivers whose
 planes only support linear layout
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On Fri, Jan 14, 2022 at 03:42:54PM +0000, Simon Ser wrote:
> On Friday, January 14th, 2022 at 16:17, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> 
> > On Fri, Jan 14, 2022 at 03:07:21PM +0000, Simon Ser wrote:
> > > On Friday, January 14th, 2022 at 15:16, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > >
> > > > Why not enum?
> > >
> > > There is no enum for DRM format modifiers.
> >
> > I'm not sure how this prevents to use enum in the code instead of const u64.
> > Any specific reason for that?
> 
> I'm not sure how one would use an enum as the array item type, when there is no
> defined enum type.
> 
> Moreover, all the rest of DRM uses uint64 for modifiers.

Ah, I see now. This is an array that filled by predefined values.
Thanks for explanation.

-- 
With Best Regards,
Andy Shevchenko