Re: [PATCH] arm64: dts: imx8mp: Enable HDMI on i.MX8MP DHCOM PDK2 and PDK3

[Marek Vasut]

On 5/16/24 1:36 PM, Ahmad Fatoum wrote:
> Hello Marek,

Hi,

> On 16.05.24 13:14, Marek Vasut wrote:
> > On 5/16/24 10:00 AM, Francesco Dolcini wrote:
> > > Hello Marek,
> >
> > Hi,
> >
> > > On Tue, May 14, 2024 at 03:06:42AM +0200, Marek Vasut wrote:
> > > > Enable HDMI output on i.MX8MP DHCOM PDK2 and PDK3. The I2C5 on PDK2 and
> > > > I2C mux port 1 on PDK3 respectively are used in regular I2C mode instead
> > > > of HDMI DDC mode to permit connection of other I2C devices on those buses.
> > >
> > > Are you able to read the HDMI EDID with such configuration? I have the
> > > patch ready for verdin imx8mp, I just did not have time to figure out
> > > this last details.
> >
> > Yes with ddc-i2c-bus in hdmi_tx{} node, no with ddc-i2c-bus in connector node. Maybe that's what you're running into ? The DW HDMI core needs the ddc-i2c-bus property in hdmi_tx{} node if you use non-native I2C bus for the DDC channel.
>
> What benefit does the hdmi-connector provide over just omitting it?
> Just for documentation purposes?

I was under the impression describing the hardware in DT in full was the 
best practice (TM), hence it is in full here.