Re: [RFC 00/17] OMAPDSS: Change way of passing timings from panel driver to interface

Tomi Valkeinen
2012-08-08T08:13:09Z

[-- Attachment #1: Type: text/plain, Size: 1252 bytes --]

On Wed, 2012-08-08 at 13:29 +0530, Archit Taneja wrote:

> Okay, one thing which I want to align on is that most of these functions
> don't really do the actual configurations. That is, they'll just update
> the private data, and the actual configuration will only happen on enable.
>
> We would want set_timings() op to have a direct impact. But we wouldn't
> want the same for setting the data lines, that could be clubbed with
> other configurations at enable. That's okay, right?

I'm not sure we want/need set_timings to have direct impact. Changing
the timings on the fly has some problems, like the output size changing
to smaller than the overlays, and we perhaps may need to adjust the
clock dividers (dispc's, DSI PLL's or PRCM's).

It feels just much easier and safer to require that the mgr is disabled
when these changes are made. And as far as I can see, there shouldn't be
any need to change the timings via the shadow registers, as quickly as
possible and during vblank...

This makes me also think that if the output related settings can only be
changed when the output is off, the apply mechanism is not really needed
at all for these. Not that it causes any harm, but just a point I
realized.

Tomi

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 836 bytes --]