[PATCH V2 3/3] arm64: dts: rockchip: Enable HDMI0 on Indiedroid Nova

[Heiko Stübner]

Am Donnerstag, 31. Oktober 2024, 01:49:07 CET schrieb Jimmy Hon:
> On Wed, Oct 30, 2024 at 2:25 PM Chris Morgan <macroalpha82 at gmail.com> wrote:
> >
> > From: Chris Morgan <macromorgan at hotmail.com>
> >
> > Enable the HDMI0 port for the Indiedroid Nova. The schematics available
> > show the hdmim0_rx_hpdin is connected, so this pinctrl is enabled in
> > contrast with the other rk3588 boards.
> 
> Which pin in the schematic [1] (page 24) does it refer to? It's not
> obvious how to match it up.
> The schematic looks the same as the Rock 5B schematic [2] (page 31)
> and the Rock 5B dts uses the default pinctrl [3]
> 
> Note: The vendor kernel DTS doesn't modify the pinctrl either. [4]
> 
> If you try using the default pinctrl (not overriding), does HDMI not work?

I stumbled over the same issue recently for our Theobroma boards too.

From the Indiedroid schematics, you can see that the hdmim0_rx_hpdin
pin is gpio4_b6, which in their board is connected to the hdmi0_tx_on_h
functionality, which controls the output functionality between hdmi2.0-tmds
and hdmi2.1-frl modes.

The hdmi-driver currently only does hdmi2.0 but normally, on most boards
I've seen so far, this pin has a default pull to set hdmi2.0 anyway, so other
boards don't need that.

So for one, please check if the nova can run without it, but if a pin
setting is needed, please define a new per-board one, labeling it correctly
for this hdmi0_tx_on_h functionality and do not re-use the hdmi-rx
pin-setting.


Heiko