Re: Problems with the omap3isp

Laurent Pinchart
2014-08-28T12:02:38Z

Hi Stefan,

On Wednesday 27 August 2014 12:24:46 Stefan Herbrechtsmeier wrote:
> Am 04.08.2014 um 17:25 schrieb Laurent Pinchart:
> > On Monday 04 August 2014 11:24:13 Stefan Herbrechtsmeier wrote:
> >> Hi Laurent,
> >>
> >> thank you very much for your help.
> >>
> >> The problem is cross talk on the camera flex cable of the Gumstix Overo.
> >> The XCLKA signal is beside PCLK and VS.
> >
> > Right, I should have mentioned that. It's a know issue, and there's not
> > much that can be done about it without a hardware redesign. A ground (or
> > power supply) signal should really have been inserted on each side of the
> > XCLKA and PCLK signals.
>
> Exists a list about knowing issues with the Gumstix Overo? Because I
> have some problems with the MMC3 too.

Not to my knowledge. This crosstalk issue is something I've discovered and
reported to Gumstix a couple of years ago.

> >> Additionally the OV5647 camera tristate all outputs by default. This
> >> leads to HS_VS_IRQ interrupts.
> >
> > This should be taken care of by pull-up or pull-down resistors on the
> > camera signals. I've disabled them with the Caspa camera given the low
> > drive strength of the buffer on the camera board, but you could enable
> > them on your system.
>
> I have manually rework my camera adapter and change the camera clock
> from XCLKA to XCLKB. Additionally I have enable the pull-ups in my
> device tree. Now the camera sensor from the Raspberry Pi camera module
> works together with the Gumstix Overo.

Great. Any chance to see a driver for the ov5647 being submitted to the linux-
media mailing list ? :-)