In the DTs, the OLDIs are not modeled at all. Since the DSS only has aEven in DT, the dss port (for OLDI) connects to the panel port's
endpoint directly. Even in cases of dual link or cloning, it's only a
singular remote-to-endpoint connection between the (OLDI) VP and the
panel port. Hence the requirement of the properties in the earlier
patches of the series.
Sorry, I don't follow. If you use cloning, you have two TX outputs, going to two panels, right? So you need two panel DT nodes, and those would connect to two OLDI TX ports in the DSS.
> Afaics the existing dual link bridge/panel drivers also use two ports
for the connection, so to use the dual link you need two ports in the DSS.
I admit I'm not familiar with LVDS dual link, but it's not clear to me how you see the dual OLDI TX being used with other drivers if you have only one port. What kind of setups have you tested?
single VP for OLDI, the DT dss port (for OLDI) is connected to a single
simple-panel node for dual link, bypassing the OLDI TX in DT. I have
this same OLDI setup and have been testing on this.
I do not have a cloning display setup with me, but I have seen DT DSS
port connected to one of 2 panel nodes while the other panel (remains as
a companion panel to the first) without any endpoint connections. Since,
the OLDI TXes (0 and 1), receive the same clocks and inputs from DSS
OLDI VP, this 'method' has worked too.
The drm_of.c helpers use DT properties to ascertain the presence of aThe use of lvds helper functions does not seem feasible in this case,
because even they read DT properties to determine the dual link
connection and those properties need to be a part of a lvds bridge
device.
Can you elaborate a bit more why the DRM helpers couldn't be used here?
dual-link connection. While there wasn't a specific helper to determine
dual-link or not, the drivers use the odd/even pixel order helper which
is based on the properties "dual-lvds-odd-pixels" and "dual-lvds-odd-
pixels". If either of the properties are absent, the helper returns an
error making the driver to use single link.
These properties are LVDS specific, but they could not be added in the
DT because there is no OLDI TX DT node for our case.
Okay...I have also been considering the idea of implementing a new device
driver for the OLDI TXes, not unlike the renesas' one. That way the
driver could have the properties and the lvds helper functions at their
disposal. I am just slightly unsure if that would allow space for any
conflicts because of the shared register space.
No, I don't think new devices are needed here.
I am not quite sure I understand completely what you are recommending
the OLDI to be. It seems to me that you want the OLDI TXes to be modeled
as nodes, right? Wouldn't that automatically require some sort of
standalone driver arrangement for them? Or am I missing something
important here?