Re: [PATCH 2/5] media: dt-bindings: Add bindings for TDA1997X

From: Sakari Ailus
Date: Thu Nov 23 2017 - 03:25:49 EST


On Wed, Nov 22, 2017 at 08:37:04PM -0800, Tim Harvey wrote:
> On Tue, Nov 21, 2017 at 11:36 PM, Sakari Ailus <sakari.ailus@xxxxxx> wrote:
> > Hi Tim,
> >
> > On Thu, Nov 09, 2017 at 10:45:33AM -0800, Tim Harvey wrote:
> >> Cc: Rob Herring <robh@xxxxxxxxxx>
> >> Signed-off-by: Tim Harvey <tharvey@xxxxxxxxxxxxx>
> >> ---
> >> v3:
> >> - fix typo
> >>
> >> 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
> >> - update to 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..dd37f14
> >> --- /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 of connection possibilities including swapping pin order within
> >> +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.
> >> +
> >> +Required Properties:
> >> + - compatible :
> >> + - "nxp,tda19971" for the TDA19971
> >> + - "nxp,tda19973" for the TDA19973
> >> + - reg : I2C slave address
> >> + - interrupts : The interrupt number
> >> + - DOVDD-supply : Digital I/O supply
> >> + - DVDD-supply : Digital Core supply
> >> + - AVDD-supply : Analog supply
> >> + - nxp,vidout-portcfg : array of pairs mapping VP output pins to pin groups.
> >> +
> >> +Optional Properties:
> >> + - nxp,audout-format : DAI bus format: "i2s" or "spdif".
> >> + - nxp,audout-width : width of audio output data bus (1-4).
> >> + - nxp,audout-layout : data layout (0=AP0 used, 1=AP0/AP1/AP2/AP3 used).
> >> + - nxp,audout-mclk-fs : Multiplication factor between stream rate and codec
> >> + mclk.
> >> +
> >> +The device node must contain one 'port' child node for its digital output
> >> +video port, in accordance with the video interface bindings defined in
> >> +Documentation/devicetree/bindings/media/video-interfaces.txt.
> >
> > Could you add that this port has one endpoint node as well? (Unless you
> > support multiple, that is.)
>
> Sure... will clarify as:
>
> The device node must contain one endpoint 'port' child node for its
> digital output
> video port, in accordance with the video interface bindings defined in
> Documentation/devicetree/bindings/media/video-interfaces.txt.

I think it'd be clearer if you just add "The port node shall contain one
endpoint child node".

>
> >> +
> >> +Optional Endpoint Properties:
> >> + The following three properties are defined in video-interfaces.txt and
> >> + are valid for source endpoints only:
> >
> > Transmitters? Don't you have an endpoint only in the port representing the
> > transmitter?
>
> I'm not usre what you mean.
>
> The TDA1997x is an HDMI receiver meaning it receives HDMI and decodes
> it to a parallel video bus. HDMI transmitters are the opposite.

The parallel bus. If you mean that, then you could just say that. "Source
endpoint" is a bit vague, or requires knowing V4L2.

--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx