Re: [PATCH v2 1/2] drm: bridge: samsung-dsim: Initialize bridge on attach

["Michael Walle" <mwalle@kernel.org>]

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Hi,

> with more and more patches for TC9595 support got meged into linux-next,
> only a few remain on my patch stack.
>
> This is one of them and is necessary for DP support:
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>

As mentioned in [1] I expect a new version of this series with a
proper documentation update that will then (hopefully) be acked by
the maintainers.

Apart from that, I'm still not convinced that the .attach() callback
is the correct place to put the lanes into LP-11 mode. E.g. the
MediaTek DSI host needs to already know the HS clock rate before
configuring the D-PHY. Something which isn't available at the time
.attach() is called. Marek mentioned, that one should start with
lowest possible clock rate and later reconfigure it to the correct
rate. I'm not sure this is possible without taking the clock lanes
out of LP-11 mode again (i.e. disabling the PHY altogether to change
its PLL). But doing so will violate the bridge requirements again.

-michael

[1] https://lore.kernel.org/dri-devel/D2R83VFPUWE3.3MBX3LQOCDFWA@kernel.org/

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