On Fri, Feb 28, 2014 at 06:15:05PM +0200, Tomi Valkeinen wrote:
> On 28/02/14 18:06, Russell King - ARM Linux wrote:
>
> >> +hdmi0: connector@1 {
> >> + compatible = "hdmi-connector";
> >> + label = "hdmi";
> >> +
> >> + hdmi_connector_in: endpoint {
> >> + remote-endpoint = <&tpd12s015_out>;
> >> + };
> >> +};
> >
> > It seems rather weird to have DVI connectors having an optional I2C
> > property, but HDMI (which augments DVI) not having that as at least an
> > optional property.
>
> I have added only the properties that I have used. I did think about the
> i2c for HDMI also, but thought that I don't use it, and so can't test
> it, and so I could well create a bad binding.
>
> And, as I don't see any issue in adding it later, when someone uses it,
> I decided to leave it out.
>
> > I can quite well see the iMX HDMI support needing an i2c bus here.
> >
> > Also, HDMI has two connector standards - type A and type B, much like
> > the single vs dual link of DVI. Again, DRM exposes this to userspace.
>
> True, but isn't that just a form factor? No functional differences? But
> I agree, we can add the two types here also to the compatible string.
HDMI A is 19 pins carrying TMDS channels 0-2. HDMI B is 29 pins
carrying TMDS channels 0-5. So, the difference is the same as the
single vs dual link on DVI-D/I connectors.
There's actually three HDMI connectors:
All three connectors carry all required HDMI signals, including a TMDS
link. The Type B connector is slightly larger and carries a second TMDS
link, which is necessary to support very high resolution displays using
dual link. The Type C connector carries the same signals as the Type A
but is more compact and intended for mobile applications.
So, Type C and Type A are electrically the same.
--
FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly
improving, and getting towards what was expected from it.
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
