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Subject: Re: Proposal for a low-level Linux display framework
From: Tomi Valkeinen <tomi.valkeinen@ti.com>
To: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
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Date: Wed, 21 Sep 2011 09:01:15 +0300
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On Tue, 2011-09-20 at 23:20 +0200, Patrik Jakobsson wrote:

> Ok, not sure I understand the complexity of DSI. Can overlay composition
> occur after/at the DSI stage (through MCS perhaps)? Or is it a matter of
> panels requiring special scanout buffer formats that for instance V4L needs
> to know about in order to overlay stuff properly? Or am I getting it all wrong?

I don't know what MCS is. But DSI is just a bi-directional transfer
protocol between the SoC and the peripheral, you can send arbitrary data
over it.

Normally the SoC composes a pixel stream using overlays and whatnot,
which goes to the DSI hardware, which then serializes the data and sends
it to the peripheral.

But you can as well send any data, like commands, and the peripheral can
respond with any relevant data.

 Tomi