Re: [PATCH] samsung-laptop: Set keyboard backlight initially

From: Corentin Chary
Date: Thu Jan 03 2013 - 15:46:04 EST

Sorry for the lag...

On Mon, Dec 24, 2012 at 12:55 PM, Roland Stigge <stigge@xxxxxxxxx> wrote:
> On 24/12/12 09:41, Corentin Chary wrote:
>> On Sun, Dec 23, 2012 at 6:21 PM, Roland Stigge <stigge@xxxxxxxxx> wrote:
>>> After boot, /sys/devices/platform/samsung/leds/samsung::kbd_backlight/brightness
>>> shows the maximum value (8) by readout, but the led is off. I need to manually
>>> set it to the respective value to have keyboard backlight.
>> If the led is set to 0, what's the value after reboot ? 0 or 8 ?
> Right - when writing 0 there before restart, the led value is actually 8
> after reboot, and the LED hardware is ON. This holds for both reboot and
> halt+poweron cycle.


> Maybe this is related to the "#define MAX_BRIGHT 0x07" (which is unused
> in samsung-laptop.c)? A bit confusing in the code - but your question
> hints for some other bug (to be solved differently). Tell me if I can
> help somehow, here.

I don't think this is really used.

>> What's the behavior on windows ?
> There is no windows available on this machine.

Too bad, let's assume your patch is the best behavior :). Will merge it soon.

Corentin Chary
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