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Date:   Mon, 17 Jan 2022 14:15:48 +0900
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Subject: Re: [RFC PATCH v3 2/3] drm: add support modifiers for drivers whose
 planes only support linear layout
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To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     dri-devel@lists.freedesktop.org,
        Alex Deucher <alexander.deucher@amd.com>,
        =?UTF-8?Q?Christian_K=c3=b6nig?= <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>,
        =?UTF-8?Q?Michel_D=c3=a4nzer?= <mdaenzer@redhat.com>,
        Simon Ser <contact@emersion.fr>,
        Qingqing Zhuo <qingqing.zhuo@amd.com>,
        Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>,
        Mark Yacoub <markyacoub@chromium.org>,
        Sean Paul <seanpaul@chromium.org>,
        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>,
        amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        nouveau@lists.freedesktop.org, Daniel Stone <daniel@fooishbar.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Damian Hobson-Garcia <dhobsong@igel.co.jp>,
        Takanari Hayama <taki@igel.co.jp>
References: <20220114101753.24996-1-etom@igel.co.jp>
 <20220114101753.24996-3-etom@igel.co.jp>
 <YeGFugZvwbF7l2I/@smile.fi.intel.com>
From:   Esaki Tomohito <etom@igel.co.jp>
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Thank you for your reviews.

On 2022/01/14 23:16, Andy Shevchenko wrote:
> On Fri, Jan 14, 2022 at 07:17:52PM +0900, Tomohito Esaki wrote:
>> The LINEAR modifier is advertised as default if a driver doesn't specify
>> modifiers.
> 
> ...
> 
>> +	const uint64_t default_modifiers[] = {
>> +		DRM_FORMAT_MOD_LINEAR,
>> +		DRM_FORMAT_MOD_INVALID
> 
> + Comma?

There is no mention in the coding style about adding/removing a comma to 
the last element of an array. Is there a policy in drm driver?

I think the advantage of adding a comma to the last element of an array 
is that diff is only one line when an element is added to the end.
However since INVALID is always the last element in the modifiers array, 
I think it can be either in this case.
If there is a policy, I will match it.

Thanks,
Tomohito Esaki