Re: [PATCH] Platform: add Samsung Laptop platform driver

[Richard SchÃtz]

> Every time I execute this in the /sys/class/backlight/samsung directory:
> sudo bash -c 'echo 1 > brightness'
> brightness is reduced a little until it reaches the minimum.
>
> After that, every time I execute this:
> sudo bash -c 'echo 8 > brightness'
> it increases a little until it reaches the maximum.
>
> And each time a message appears in dmesg: "ACPI: Failed to switch the
> brightness", until the brightness stops changing.
>
> At the same time, the little Gnome brightness adjustment window appears,
> showing the percentage of the brightness, which drops/raises to
> minimum/maximum in only four executions of these commands. After that,
> while
> brightness drops/raises with each execution, the percentage stays at
> minimum/maximum.
>
> Is this all normal?

That sounds like the driver is interfering with the ACPI video driver. 
Add "acpi_backlight=vendor" to your kernel boot parameters and try again.

--
Regards,
Richard SchÃtz
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