Re: [PATCH v2 04/10] media: imx: interweave only for sequential input/interlaced output fields

[khalasa@piap.pl (Krzysztof Hałasa)]

Philipp Zabel <p.zabel@pengutronix.de> writes:

> This is ok in this patch, but we can't use this check in the following
> TRY_FMT patch as there is no way to interweave
> SEQ_TB -> INTERLACED_BT (because in SEQ_TB the B field is newer than T,
> but in INTERLACED_BT it has to be older) or SEQ_BT -> INTERLACED_TB (the
> other way around).

Actually we can do SEQ_TB -> INTERLACED_BT and SEQ_BT -> INTERLACED_TB
rather easily. We only need to skip a single field at start :-)
That's what CCIR_CODE_* registers do.

To be honest, SEQ_TB and SEQ_BT are precisely the same thing
(i.e., SEQUENTIAL). It's up to the user to say which field is the first.
There is the progressive sensor exception, though, and the TB/BT could
be a hint for downstream elements (i.e., setting the default field
order).

But I think we should be able to request INTERLACED_TB or INTERLACED_BT
(with any analog signal on input) and the CCIR_CODE registers should be
set accordingly. This should all magically work fine.
-- 
Krzysztof Halasa

Industrial Research Institute for Automation and Measurements PIAP
Al. Jerozolimskie 202, 02-486 Warsaw, Poland