[PATCH v5 00/39] i.MX Media Driver

Russell King - ARM Linux linux at armlinux.org.uk
Sun Mar 19 11:51:33 PDT 2017

On Sun, Mar 19, 2017 at 11:37:15AM -0700, Steve Longerbeam wrote:
> On 03/19/2017 05:14 AM, Russell King - ARM Linux wrote:
> >Right now, CSI doesn't do that - it only looks at the width, height,
> >code, and field.
> Correct, there is currently no propagation of the colorimetry
> parameters (colorspace, ycbcr_enc, quantization, and xfer_func).
> For the most part, those are just ignored ATM. Philipp Zabel did
> do some work earlier to start propagating those, but that's still

> >
> >I think we've got other bugs though that haven't been picked up by any
> >review - csi_try_fmt() adjusts the format using the _current_
> >configuration of the sink pad, even when using V4L2_SUBDEV_FORMAT_TRY.
> >This seems wrong according to the docs: the purpose of the try
> >mechanism is to be able to setup the _entire_ pipeline using the TRY
> >mechanism to work out whether the configuration works, before then
> >setting for real.  If we're validating the TRY formats against the
> >live configuration, then we're not doing that.
> I don't believe that is correct. csi_try_fmt() for the source pads calls
> __csi_get_fmt(priv, cfg, CSI_SINK_PAD, sdformat->which) to get
> the sink format, and for the TRY trial-run from csi_set_fmt(),
> sdformat->which will be set to TRY, so the returned sink format
> is the TRY format.

Look at csi_try_fmt() - it validates the source pad against
priv->crop, which is the actively live cropping rectangle, not the
one which has been configured for the TRY trial-run.

Also, as I mention elsewhere, I believe the way we're doing scaling
is completely wrong...

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