Re: [RFC] adp1653: Add device tree bindings for LED controller

Pavel Machek
2014-11-18T16:51:54Z

Hi!

> >If the hardware LED changes with one that needs different current, the
> >block for the adp1653 stays the same, but white LED block should be
> >updated with different value.
>
> I think that you are talking about sub nodes. Indeed I am leaning
> towards this type of design.

I think I am :-).

> >>I agree that flash-timeout should be per led - an array, similarly
> >>as in case of iout's.
> >
> >Agreed about per-led, disagreed about the array. As all the fields
> >would need arrays, and as LED system currently does not use arrays for
> >label and linux,default-trigger, I believe we should follow existing
> >design and model it as three devices. (It _is_ physically three devices.)
>
> Right, I missed that the leds/common.txt describes child node.
>
> I propose following modifications to the binding:
>
> Optional properties for child nodes:
> - iout-mode-led : maximum intensity in microamperes of the LED
> (torch LED for flash devices)
> - iout-mode-flash : initial intensity in microamperes of the
> flash LED; it is required to enable support
> for the flash led
> - iout-mode-indicator : initial intensity in microamperes of the
> indicator LED; it is required to enable support
> for the indicator led
> - max-iout-mode-led : maximum intensity in microamperes of the LED
> (torch LED for flash devices)
> - max-iout-mode-flash : maximum intensity in microamperes of the
> flash LED
> - max-iout-mode-indicator : maximum intensity in microamperes of the
> indicator LED
> - flash-timeout : timeout in microseconds after which flash
> led is turned off

Ok, I took a look, and "iout" is notation I understand, but people may
have trouble with and I don't see it used anywhere else.

Also... do we need both "current" and "max-current" properties?

But regulators already have "regulator-max-microamp" property. So what
about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support
for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

...would do?

> I propose to avoid name "torch", as for ordinary leds it would
> be misleading.

Agreed.

Thanks,
Pavel
--
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