On 12/6/24 11:46 AM, Sverdlin, Alexander wrote:
Hi Andrew,
On Fri, 2024-12-06 at 11:43 -0600, Andrew Davis wrote:
Are you sure this is a correct thing to do? The lp8860-q1 product link
cites it as being a 4-channel device. Even if the kernel only ever
supports it as a single-channel device, the binding should reflect what
it is capable of doing.
Agree, the driver today just checks the first child node, but it could
be extended for all 4 supported LED channels, and we shouldn't have
to change the binding for that new support.
but the channels are (in my understanding) for power-balancing only, there
are no separate controls for them. What do I miss?
I'm not very familiar with this part either, but looking at the datasheet
I see:
Supports Display Mode (Global Dimming) and
Cluster Mode (Independent Dimming)
In Cluster mode LED strings have independent control but fewer features enabled than in Display Mode.
And one channel controlling the others is only in this "Display Mode",
but the currents to the others can be independently controlled in a
different mode (seems these modes have less features which is probably
why the driver doesn't make use of that today).
Andrew
