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Date: Fri, 16 Apr 2010 11:07:57 +0100
From: Jonathan Cameron <jic23@cam.ac.uk>
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To: Stefan Herbrechtsmeier <hbmeier@hni.uni-paderborn.de>
CC: Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
	Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: pxa_camera + ov9655: image shifted on first capture after reset
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On 04/16/10 09:25, Stefan Herbrechtsmeier wrote:
> Hi,
> 
> I have updated my ov9655 driver to kernel 2.6.33 and
> did some test regarding the image shift problem on pxa.
> (http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/10773/focus=11810)
> 
> 
> - The image was shifted 32 pixels (64 bytes) to the right
>  or rather the first 32 pixels belongs to the previous image.
> - The image was only shifted on the first capture after reset.
>   It doesn't matter whether I previous change the resolution with v4l2-ctl.
> - On big images (1280 x 1024) the shift disappears after some images,
>   but not on small images (320 x 240).
> 
> It looks like the FIFO was not cleared at start capture.
> 
Sounds reasonable.  Similar problem seen with ov7670 attached to pxa271.
I've never taken the time to try and track it down.