RE: [PATCH v1 2/2] media: atmel-isc: Update device tree binding documentation

[Ken Sloat <KSloat@aampglobal.com>]

> From: Hans Verkuil <hverkuil@xs4all.nl>
> Sent: Tuesday, January 8, 2019 8:46 AM
> To: Ken Sloat <KSloat@aampglobal.com>; eugen.hristev@microchip.com
> Cc: mchehab@kernel.org; nicolas.ferre@microchip.com;
> alexandre.belloni@bootlin.com; ludovic.desroches@microchip.com; linux-
> media@vger.kernel.org
> Subject: Re: [PATCH v1 2/2] media: atmel-isc: Update device tree binding
> documentation
> 
> On 01/08/19 14:44, Hans Verkuil wrote:
> > On 12/28/18 17:59, Ken Sloat wrote:
> >> From: Ken Sloat <ksloat@aampglobal.com>
> >>
> >> Update device tree binding documentation specifying how to enable
> >> BT656 with CRC decoding.
> >>
> >> Signed-off-by: Ken Sloat <ksloat@aampglobal.com>
> >> ---
> >>  Documentation/devicetree/bindings/media/atmel-isc.txt | 3 +++
> >>  1 file changed, 3 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/media/atmel-isc.txt
> >> b/Documentation/devicetree/bindings/media/atmel-isc.txt
> >> index bbe0e87c6188..e787edeea7da 100644
> >> --- a/Documentation/devicetree/bindings/media/atmel-isc.txt
> >> +++ b/Documentation/devicetree/bindings/media/atmel-isc.txt
> >> @@ -25,6 +25,9 @@ ISC supports a single port node with parallel bus.
> >> It should contain one  'port' child node with child 'endpoint' node.
> >> Please refer to the bindings  defined in
> Documentation/devicetree/bindings/media/video-interfaces.txt.
> >>
> >> +If all endpoint bus flags (i.e. hsync-active) are omitted, then
> >> +CCIR656 decoding (embedded sync) with CRC decoding is enabled.
> >
> > Sorry, this is wrong. There is a bus-type property defined in
> > video-interfaces.txt that you should use to determine whether this is a
> parallel or a Bt.656 bus.
> 
> Actually, that's what your code already does, so it seems this text in the
> bindings doc is just plain wrong.
> 
> 	Hans
> 
> >
> > BTW, for v2 also CC this to devicetree@vger.kernel.org, since it has
> > to be reviewed by the DT maintainers.
> >
> > Regards,
> >
> > 	Hans
> >
> >> +
> >>  Example:
> >>  isc: isc@f0008000 {
> >>  	compatible = "atmel,sama5d2-isc";
> >>
> >

Hi Hans,

My apologies you are correct. The way I documented it here was the old way of doing it in the kernel but still worked for my setup as it appears the v4l2 subsystem still makes the assumption of 656 mode if these flags are all omitted. I will update with the proper "bus-type" property and resubmit here copying the dt list as well.

Thanks,
Ken