Re: [PATCH] [media] imx: csi: retain current field order and colorimetry setting as default

From: Russell King - ARM Linux
Date: Thu Apr 06 2017 - 11:11:53 EST


On Thu, Apr 06, 2017 at 05:01:52PM +0200, Philipp Zabel wrote:
> On Thu, 2017-04-06 at 15:05 +0100, Russell King - ARM Linux wrote:
> > On Thu, Apr 06, 2017 at 03:55:29PM +0200, Philipp Zabel wrote:
> > > +
> > > + /* Retain current field setting as default */
> > > + if (sdformat->format.field == V4L2_FIELD_ANY)
> > > + sdformat->format.field = fmt->field;
> > > +
> > > + /* Retain current colorspace setting as default */
> > > + if (sdformat->format.colorspace == V4L2_COLORSPACE_DEFAULT) {
> > > + sdformat->format.colorspace = fmt->colorspace;
> > > + if (sdformat->format.xfer_func == V4L2_XFER_FUNC_DEFAULT)
> > > + sdformat->format.xfer_func = fmt->xfer_func;
> > > + if (sdformat->format.ycbcr_enc == V4L2_YCBCR_ENC_DEFAULT)
> > > + sdformat->format.ycbcr_enc = fmt->ycbcr_enc;
> > > + if (sdformat->format.quantization == V4L2_QUANTIZATION_DEFAULT)
> > > + sdformat->format.quantization = fmt->quantization;
> > > + } else {
> > > + if (sdformat->format.xfer_func == V4L2_XFER_FUNC_DEFAULT) {
> > > + sdformat->format.xfer_func =
> > > + V4L2_MAP_XFER_FUNC_DEFAULT(
> > > + sdformat->format.colorspace);
> > > + }
> > > + if (sdformat->format.ycbcr_enc == V4L2_YCBCR_ENC_DEFAULT) {
> > > + sdformat->format.ycbcr_enc =
> > > + V4L2_MAP_YCBCR_ENC_DEFAULT(
> > > + sdformat->format.colorspace);
> > > + }
> > > + if (sdformat->format.quantization == V4L2_QUANTIZATION_DEFAULT) {
> > > + sdformat->format.quantization =
> > > + V4L2_MAP_QUANTIZATION_DEFAULT(
> > > + cc->cs != IPUV3_COLORSPACE_YUV,
> > > + sdformat->format.colorspace,
> > > + sdformat->format.ycbcr_enc);
> > > + }
> > > + }
> >
> > Would it make sense for this to be a helper function?
>
> Quite possible, the next subdev that has to set frame_interval on both
> pads manually because its upstream source pad doesn't suport
> frame_interval might want to do the same.

Hmm. I'm not sure I agree with this approach. If a subdev hardware
does not support any modification of the colourspace or field, then
it should not be modifyable at the source pad - it should retain the
propagated settings from the sink pad.

I thought I had already sent a patch doing exactly that.

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