Bug 43051

Summary:	Inverted values for actual_brightness
Product:	ACPI	Reporter:	Manuel Razola (mrazola)
Component:	Power-Video	Assignee:	acpi_power-video
Status:	CLOSED INSUFFICIENT_DATA
Severity:	normal	CC:	lenb, rui.zhang, tianyu.lan
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	3.0.0-17	Subsystem:
Regression:	No	Bisected commit-id:
Attachments:	acpi dump debug.patch debug.patch

Description Manuel Razola 2012-04-05 13:49:36 UTC

/sys/class/backlight/acpi_video0/actual_brightness

has inverted values that doesn't correspond with what we can write in /sys/class/backlight/acpi_video0/brightness


For example, when doing:
"echo 8 > /sys/class/backlight/acpi_video0/brightness"

and then:
"cat /sys/class/backlight/acpi_video0/actual_brightness",

it outputs 2. It should output 8.

Comment 1 Lan Tianyu 2012-04-09 14:09:33 UTC

Please attach the output of acpidump.

Comment 2 Manuel Razola 2012-04-09 14:55:34 UTC

Created attachment 72862 [details]
acpi dump

Comment 3 Lan Tianyu 2012-04-11 02:55:50 UTC

Does the problems still exist in the latest upstream kernel?

Comment 4 Lan Tianyu 2012-04-11 06:27:19 UTC

Created attachment 72876 [details]
debug.patch

Please try this patch and update driver since the acpi video driver is only available as driver module. Attach the output of dmesg.

Comment 5 Manuel Razola 2012-04-11 09:30:10 UTC

Couldn't compile new video.c file:

~/video.c: In function ‘acpi_video_get_brightness’:
~/video.c:247:5: error: ‘device’ undeclared (first use in this function)

Comment 6 Lan Tianyu 2012-04-11 12:41:29 UTC

Created attachment 72885 [details]
debug.patch

oh. Sorry. Please try this one.

Comment 7 Lan Tianyu 2012-04-17 03:07:54 UTC

ping ...

Comment 8 Zhang Rui 2012-11-13 07:51:16 UTC

bug closed as there is no response from the bug reporter.

Manuel, please feel free to reopen it if the problem still exist or you can provide the info requested in comment #6