Hi! > > >> By the way I just realized that the DT binding in this driver seems > > >> incorrect to me. > > >> > > >> The controller logically supports 3 LED strings, each having > > >> configurable control bank. > > > > There are two control banks. You can connect the HVLED outputs to either > > control bank A or B there is no individual control of the LED strings. > > > > > > >> But the DT binding supports 2 DT nodes, one for each control bank > > >> (identified by the `reg` property) and then `led-sources` says which > > >> string should be controlled by given bank. > > >> > > >> But taking in mind that DT should describe how devices are connected to > > >> each other, I think the child nodes in the binding should instead > > >> describe the 3 supported LED strings... > > > > The outputs in this case are virtual outputs which are the banks (A and B). > > > > Since the device is bank controlled the actual current sinks are not > > defined thus making the the banks the actual outputs. > > > > This is why the 'reg' property defines the control bank either A or B > > and the led-sources indicates the strings associated with the control bank.
> Dan, I looked at the datasheet, I understand this.
>
> Nonetheless, device tree should describe how devices are connected to
> each other. The chip has 3 pins for 3 LED strings.
Well, device tree is not a device schematics...
> If this controller should be able to support 3 LED strings via 3
> outputs, the device tree binding nodes should, in my opinion, describe
> each pin connected string. The nodes should maybe even be called
> 'led-string@N' where N is from [0, 1, 2].
>
> The fact that the device is bank controlled and there are only two
> banks (and it is configurable by which bank each LED string is
> controlled) is more relevant to the driver, not as much to device tree
> binding.
Seems to me like two independend LEDs, and I'd describe it as
such. The fact that it goes over 3 wires is just a implementation
detail. Lets keep it simple...
Best regards,
Pavel
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