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Date: Sat, 18 Feb 2017 09:23:35 +0000
From: Russell King - ARM Linux <linux@armlinux.org.uk>
To: Steve Longerbeam <slongerbeam@gmail.com>
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Subject: Re: [PATCH v4 29/36] media: imx: mipi-csi2: enable setting and
 getting of frame rates
Message-ID: <20170218092335.GI21222@n2100.armlinux.org.uk>
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On Fri, Feb 17, 2017 at 05:12:44PM -0800, Steve Longerbeam wrote:
> Hi Russell,
> 
> I signed-off on this but after more review I'm not sure this is right.
> 
> The CSI-2 receiver really has no control over frame rate. It's output
> frame rate is the same as the rate that is delivered to it.
> 
> So this subdev should either not implement these ops, or it should
> refer them to the attached source subdev.

Where in the V4L2 documentation does it say that is permissible?

If you don't implement these, media-ctl fails to propagate _anything_
to the next sink pad if you specify a frame rate, because media-ctl
throws an error and exits immediately.

-- 
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