% ls -l /sys/class/backlight
total 0
lrwxrwxrwx 1 root root 0 Jan 28 18:21 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight
lrwxrwxrwx 1 root root 0 Jan 28 18:24 sony -> ../../devices/virtual/backlight/sony
% ls -lR /sys/class/backlight/*/
/sys/class/backlight/intel_backlight/:
total 0
-r--r--r-- 1 root root 4096 Jan 28 18:21 actual_brightness
-rw-r--r-- 1 root root 4096 Jan 28 18:27 bl_power
-rw-r--r-- 1 root root 4096 Jan 28 18:21 brightness
lrwxrwxrwx 1 root root    0 Jan 28 18:27 device -> ../../card0-LVDS-1
-r--r--r-- 1 root root 4096 Jan 28 18:21 max_brightness
drwxr-xr-x 2 root root    0 Jan 28 18:27 power
lrwxrwxrwx 1 root root    0 Jan 28 18:21 subsystem -> ../../../../../../../class/backlight
-r--r--r-- 1 root root 4096 Jan 28 18:27 type
-rw-r--r-- 1 root root 4096 Jan 28 18:21 uevent

/sys/class/backlight/intel_backlight/power:
total 0
-rw-r--r-- 1 root root 4096 Jan 28 18:27 async
-rw-r--r-- 1 root root 4096 Jan 28 18:27 autosuspend_delay_ms
-rw-r--r-- 1 root root 4096 Jan 28 18:27 control
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_active_kids
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_active_time
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_enabled
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_status
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_suspended_time
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_usage

/sys/class/backlight/sony/:
total 0
-r--r--r-- 1 root root 4096 Jan 28 18:24 actual_brightness
-rw-r--r-- 1 root root 4096 Jan 28 18:25 bl_power
-rw-r--r-- 1 root root 4096 Jan 28 18:25 brightness
-r--r--r-- 1 root root 4096 Jan 28 18:24 max_brightness
drwxr-xr-x 2 root root    0 Jan 28 18:25 power
lrwxrwxrwx 1 root root    0 Jan 28 18:25 subsystem -> ../../../../class/backlight
-r--r--r-- 1 root root 4096 Jan 28 18:25 type
-rw-r--r-- 1 root root 4096 Jan 28 18:25 uevent

/sys/class/backlight/sony/power:
total 0
-rw-r--r-- 1 root root 4096 Jan 28 18:27 async
-rw-r--r-- 1 root root 4096 Jan 28 18:27 autosuspend_delay_ms
-rw-r--r-- 1 root root 4096 Jan 28 18:27 control
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_active_kids
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_active_time
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_enabled
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_status
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_suspended_time
-r--r--r-- 1 root root 4096 Jan 28 18:27 runtime_usage
% for file in $(find /sys/class/backlight/*/ -type f); do echo $file; cat $file; echo; done
/sys/class/backlight/intel_backlight/uevent

/sys/class/backlight/intel_backlight/bl_power
817965056

/sys/class/backlight/intel_backlight/brightness
4638

/sys/class/backlight/intel_backlight/actual_brightness
4638

/sys/class/backlight/intel_backlight/max_brightness
4882

/sys/class/backlight/intel_backlight/type
raw

/sys/class/backlight/intel_backlight/power/async
disabled

/sys/class/backlight/intel_backlight/power/runtime_status
unsupported

/sys/class/backlight/intel_backlight/power/runtime_usage
0

/sys/class/backlight/intel_backlight/power/runtime_active_kids
0

/sys/class/backlight/intel_backlight/power/runtime_enabled
disabled

/sys/class/backlight/intel_backlight/power/control
auto

/sys/class/backlight/intel_backlight/power/runtime_suspended_time
0

/sys/class/backlight/intel_backlight/power/runtime_active_time
0

/sys/class/backlight/intel_backlight/power/autosuspend_delay_ms
cat: /sys/class/backlight/intel_backlight/power/autosuspend_delay_ms: Input/output error

/sys/class/backlight/sony/uevent

/sys/class/backlight/sony/bl_power
0

/sys/class/backlight/sony/brightness
-1

/sys/class/backlight/sony/actual_brightness
-1

/sys/class/backlight/sony/max_brightness
7

/sys/class/backlight/sony/type
platform

/sys/class/backlight/sony/power/async
disabled

/sys/class/backlight/sony/power/runtime_status
unsupported

/sys/class/backlight/sony/power/runtime_usage
0

/sys/class/backlight/sony/power/runtime_active_kids
0

/sys/class/backlight/sony/power/runtime_enabled
disabled

/sys/class/backlight/sony/power/control
auto

/sys/class/backlight/sony/power/runtime_suspended_time
0

/sys/class/backlight/sony/power/runtime_active_time
0

/sys/class/backlight/sony/power/autosuspend_delay_ms
cat: /sys/class/backlight/sony/power/autosuspend_delay_ms: Input/output error

% ls -lR /sys/class/dmi/id/
/sys/class/dmi/id/:
total 0
-r--r--r-- 1 root root 4096 Jan 28 18:28 bios_date
-r--r--r-- 1 root root 4096 Jan 28 18:21 bios_vendor
-r--r--r-- 1 root root 4096 Jan 28 18:28 bios_version
-r--r--r-- 1 root root 4096 Jan 28 18:28 board_asset_tag
-r--r--r-- 1 root root 4096 Jan 28 18:28 board_name
-r-------- 1 root root 4096 Jan 28 18:28 board_serial
-r--r--r-- 1 root root 4096 Jan 28 18:21 board_vendor
-r--r--r-- 1 root root 4096 Jan 28 18:28 board_version
-r--r--r-- 1 root root 4096 Jan 28 18:28 chassis_asset_tag
-r-------- 1 root root 4096 Jan 28 18:28 chassis_serial
-r--r--r-- 1 root root 4096 Jan 28 18:21 chassis_type
-r--r--r-- 1 root root 4096 Jan 28 18:28 chassis_vendor
-r--r--r-- 1 root root 4096 Jan 28 18:28 chassis_version
-r--r--r-- 1 root root 4096 Jan 28 18:28 modalias
drwxr-xr-x 2 root root    0 Jan 28 18:28 power
-r--r--r-- 1 root root 4096 Jan 28 18:20 product_name
-r-------- 1 root root 4096 Jan 28 18:28 product_serial
-r-------- 1 root root 4096 Jan 28 18:28 product_uuid
-r--r--r-- 1 root root 4096 Jan 28 18:21 product_version
lrwxrwxrwx 1 root root    0 Jan 28 18:28 subsystem -> ../../../../class/dmi
-r--r--r-- 1 root root 4096 Jan 28 18:20 sys_vendor
-rw-r--r-- 1 root root 4096 Jan 28 18:20 uevent

/sys/class/dmi/id/power:
total 0
-rw-r--r-- 1 root root 4096 Jan 28 18:28 async
-rw-r--r-- 1 root root 4096 Jan 28 18:28 autosuspend_delay_ms
-rw-r--r-- 1 root root 4096 Jan 28 18:28 control
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_active_kids
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_active_time
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_enabled
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_status
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_suspended_time
-r--r--r-- 1 root root 4096 Jan 28 18:28 runtime_usage
% for file in $(find /sys/class/dmi/id/ -type f); do echo $file; cat $file; echo; done
/sys/class/dmi/id/uevent
MODALIAS=dmi:bvnINSYDE:bvrR0070Z6:bd11/02/2010:svnSonyCorporation:pnVPCYA1V9E:pvrC9006WUT:rvnSonyCorporation:rnVAIO:rvrN/A:cvnSonyCorporation:ct10:cvrN/A:

/sys/class/dmi/id/bios_vendor
INSYDE

/sys/class/dmi/id/bios_version
R0070Z6

/sys/class/dmi/id/bios_date
11/02/2010

/sys/class/dmi/id/sys_vendor
Sony Corporation

/sys/class/dmi/id/product_name
VPCYA1V9E

/sys/class/dmi/id/product_version
C9006WUT

/sys/class/dmi/id/product_serial
cat: /sys/class/dmi/id/product_serial: Permission denied

/sys/class/dmi/id/product_uuid
cat: /sys/class/dmi/id/product_uuid: Permission denied

/sys/class/dmi/id/board_vendor
Sony Corporation

/sys/class/dmi/id/board_name
VAIO

/sys/class/dmi/id/board_version
N/A

/sys/class/dmi/id/board_serial
cat: /sys/class/dmi/id/board_serial: Permission denied

/sys/class/dmi/id/board_asset_tag
N/A

/sys/class/dmi/id/chassis_vendor
Sony Corporation

/sys/class/dmi/id/chassis_type
10

/sys/class/dmi/id/chassis_version
N/A

/sys/class/dmi/id/chassis_serial
cat: /sys/class/dmi/id/chassis_serial: Permission denied

/sys/class/dmi/id/chassis_asset_tag
N/A

/sys/class/dmi/id/modalias
dmi:bvnINSYDE:bvrR0070Z6:bd11/02/2010:svnSonyCorporation:pnVPCYA1V9E:pvrC9006WUT:rvnSonyCorporation:rnVAIO:rvrN/A:cvnSonyCorporation:ct10:cvrN/A:

/sys/class/dmi/id/power/async
disabled

/sys/class/dmi/id/power/runtime_status
unsupported

/sys/class/dmi/id/power/runtime_usage
0

/sys/class/dmi/id/power/runtime_active_kids
0

/sys/class/dmi/id/power/runtime_enabled
disabled

/sys/class/dmi/id/power/control
auto

/sys/class/dmi/id/power/runtime_suspended_time
0

/sys/class/dmi/id/power/runtime_active_time
0

/sys/class/dmi/id/power/autosuspend_delay_ms
cat: /sys/class/dmi/id/power/autosuspend_delay_ms: Input/output error

% uname -a
Linux Niukka 3.1.0-1-amd64 #1 SMP Tue Jan 10 05:01:58 UTC 2012 x86_64 GNU/Linux
% cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-3.1.0-1-amd64 root=/dev/mapper/Niukka-root ro no_console_suspend acpi_backlight=vendor
%