Re: [PATCH 1/2] ARM64: dts: meson-gxm: Add R-Box Pro

From: Kevin Hilman
Date: Wed Jan 18 2017 - 17:20:44 EST


Andreas FÃrber <afaerber@xxxxxxx> writes:

> Am 17.01.2017 um 04:06 schrieb Andreas FÃrber:
>> + leds {
>> + compatible = "gpio-leds";
>> +
>> + blue {
>> + label = "rbox-pro:blue:on";
>> + gpios = <&gpio_ao GPIOAO_9 GPIO_ACTIVE_HIGH>;
>> + default-state = "on";
>> + };
>> +
>> + red {
>> + label = "rbox-pro:red:standby";
>> + gpios = <&gpio GPIODV_28 GPIO_ACTIVE_HIGH>;
>> + default-state = "off";
>> + retain-state-suspended;
>> + panic-indicator;
>> + };
>> + };
>
> The original property names for these two were led and red. If anyone
> has better label names than the above, please speak up. Ditto for
> vega-s95. On the odroidc2 it's called alive but uses heartbeat there.
>
> The vendor device tree had a third "mcu" GPIO in the sysled node,
> GPIOAO_6, which leads to immediate power-off. I tried using
> "gpio-poweroff" to configure this pin, but that driver fails to
> initialize because some pm callback is already registered - I assume
> from psci, which apparently succeeds to power-off the system, too. For
> comparison, the S905 based Vega S95 Telos has no such mcu property. Any
> thoughts?
>
> Also, any ideas how best to switch from blue to red for suspend? Add
> pinctrl properties above? systemd service doing echo from userspace? I
> assume in Android the Amlogic sysled driver handles all that logic -
> didn't find any suspend equivalent to gpio-poweroff.

in leds-gpio, when retain-state-suspended is not set, the LED is
automatically set to value 0. I wonder if leds-gpio should grow support
to make the suspend value configurable? Or a property like
"toggle-state-suspended" ?

Kevin