Re: [PATCH 2/3] ideapad: Add nodes in sysfs

From: Corentin Chary
Date: Thu Jun 02 2011 - 07:23:04 EST

On Thu, Jun 2, 2011 at 12:14 PM, Ike Panhc <ike.pan@xxxxxxxxxxxxx> wrote:
> On 06/02/2011 05:48 PM, Corentin Chary wrote:
>> Hi Ike,
>> Why do you want to add /sys/devices/platform/ideapad/brightness and
>> Â Â /sys/devices/platform/ideapad/backlight ?
>> Both of these files should be handled by the generic backlight class
>> (using brightness and bl_power).
> This is within VPC2004. In DSDT they are different device from generic
> backlight.
> and I try bl_power but can not turning off power of whole LCD. No idea
> how screensaver do it, looks like just cut off video signal.

What I wanted to say is that you should use the generic backlight
class (!=driver) to expose these. You can look at asus-wmi.c to see
how it's done.
Then users will be able to choose the backlight implementation using
acpi_backlight=vendor or acpi_backlight=video.

Corentin Chary
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