From: Michal Lukaszek <michal.lukaszek@displaylink.com>
To: Daniel Vetter <daniel@ffwll.ch>,
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        <stephane.marchesin@gmail.com>
CC: Dave Airlie <airlied@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        Dawid Kurek <dawid.kurek@displaylink.com>
Subject: RE: [PATCH] drm/udl: Make page_flip asynchronous
Thread-Topic: [PATCH] drm/udl: Make page_flip asynchronous
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Date: Thu, 20 Jul 2017 08:54:35 +0000
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On Thursday, July 13, 2017 7:11 PM, Daniel Vetter wrote:

>>> Can't we roll this driver over to the atomic helpers instead? There
>>> you get nonblocking pretty much for free ... I'm not sure extending
>>> the old modeset code has all that much benefit really.

>> This code certainly has value by itself; it makes the driver more
>> efficient. I think the best can sometimes be the enemy of the good --
>> this code is here and written, but I don't think any of us is going to
>> tackle atomic for udl.

> Sure, I guess I should have clarified this with "If you want me to
> review and merge this, then pls look into atomic, since that seems
> actually beneficial for my own interest". I'm not paid by intel to
> review driver patches at random, but to keep overall drm in nice
> shape. Moving drivers to atomic and using more shared infrastructure
> is in that interest, reviewing random driver patches isn't.

So, what's the next step here then? This code makes udl work better, without investing a lot of effort to move everything to atomics.

Btw, this is already causing modesetting not to support page flips (while Chrome OS, having this code uses page flips with udl):
https://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/drivers/modesetting/driver.c#n1198 

Regards,
Michal Lukaszek