Re: [PATCH v2 2/4] media: dt-bindings: Add bindings for TDA1997X

From: Rob Herring
Date: Mon Oct 23 2017 - 18:22:20 EST


On Wed, Oct 11, 2017 at 09:45:04PM -0700, Tim Harvey wrote:
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Signed-off-by: Tim Harvey <tharvey@xxxxxxxxxxxxx>
> ---
> v2:
> - add vendor prefix and remove _ from vidout-portcfg
> - remove _ from labels
> - remove max-pixel-rate property
> - describe and provide example for single output port
> - use new audio port bindings
>
> ---
> .../devicetree/bindings/media/i2c/tda1997x.txt | 179 +++++++++++++++++++++
> 1 file changed, 179 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/media/i2c/tda1997x.txt
>
> diff --git a/Documentation/devicetree/bindings/media/i2c/tda1997x.txt b/Documentation/devicetree/bindings/media/i2c/tda1997x.txt
> new file mode 100644
> index 0000000..269d7f0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/tda1997x.txt
> @@ -0,0 +1,179 @@
> +Device-Tree bindings for the NXP TDA1997x HDMI receiver
> +
> +The TDA19971/73 are HDMI video receivers.
> +
> +The TDA19971 Video port output pins can be used as follows:
> + - RGB 8bit per color (24 bits total): R[11:4] B[11:4] G[11:4]
> + - YUV444 8bit per color (24 bits total): Y[11:4] Cr[11:4] Cb[11:4]
> + - YUV422 semi-planar 8bit per component (16 bits total): Y[11:4] CbCr[11:4]
> + - YUV422 semi-planar 10bit per component (20 bits total): Y[11:2] CbCr[11:2]
> + - YUV422 semi-planar 12bit per component (24 bits total): - Y[11:0] CbCr[11:0]
> + - YUV422 BT656 8bit per component (8 bits total): YCbCr[11:4] (2-cycles)
> + - YUV422 BT656 10bit per component (10 bits total): YCbCr[11:2] (2-cycles)
> + - YUV422 BT656 12bit per component (12 bits total): YCbCr[11:0] (2-cycles)
> +
> +The TDA19973 Video port output pins can be used as follows:
> + - RGB 12bit per color (36 bits total): R[11:0] B[11:0] G[11:0]
> + - YUV444 12bit per color (36 bits total): Y[11:0] Cb[11:0] Cr[11:0]
> + - YUV422 semi-planar 12bit per component (24 bits total): Y[11:0] CbCr[11:0]
> + - YUV422 BT656 12bit per component (12 bits total): YCbCr[11:0] (2-cycles)
> +
> +The Video port output pins are mapped via 4-bit 'pin groups' allowing
> +for a variety fo connection possibilities including swapping pin order within

s/fo /of /

> +pin groups. The video_portcfg device-tree property consists of register mapping
> +pairs which map a chip-specific VP output register to a 4-bit pin group. If
> +the pin group needs to be bit-swapped you can use the *_S pin-group defines.

The rest of the binding looks fine, but I have some reservations about
this. I think this should be common probably. There's been a few
bindings for display recently that deal with the interface format. Maybe
some vendor property is needed here to map a standard interface format
back to pin configuration.

Rob