Re: [PATCH] leds: gpio: support multi-level brightness

[Bjorn Andersson <bjorn@xxxxxxx>]

On Fri, Oct 4, 2019 at 8:35 AM Akinobu Mita <akinobu.mita@xxxxxxxxx> wrote:
>
> Currently, GPIO LED driver allows the GPIO properties to contain one GPIO
> phandle.  This enables to contain more than one GPIO phandle and the
> brightness of the LEDs is proportional to the number of active GPIOs.
>
> Describing multi-level brightness GPIO LED is only supported in DT.  It is
> not supported in ACPI and platform data.
>

This looks interesting.

I have a half-baked driver for the NXP PCA9956B; which is a 24-channel
LED driver, each channel with brightness control. With these LEDs
mounted in a line (like on my devboard), an interface for setting e.g.
a percentage and have the appropriate number of LEDs light up seems
like an interesting thing to pursue.

So I think this would be better represented in some more generic form,
perhaps a trigger?

Regards,
Bjorn