video/lcd: document sysfs interface

Date and KernelVersion may be wrong because the lcd
interface was introduced before git initial import.

Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-lcd b/Documentation/ABI/testing/sysfs-class-lcd
new file mode 100644
index 000000000000..35906bf7aa70
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-lcd
@@ -0,0 +1,23 @@
+What:           /sys/class/lcd/<lcd>/lcd_power
+Date:           April 2005
+KernelVersion:  2.6.12
+Contact:        Richard Purdie <rpurdie@rpsys.net>
+Description:
+                Control LCD power, values are FB_BLANK_* from fb.h
+                 - FB_BLANK_UNBLANK (0)   : power on.
+                 - FB_BLANK_POWERDOWN (4) : power off
+
+What:           /sys/class/lcd/<lcd>/contrast
+Date:           April 2005
+KernelVersion:  2.6.12
+Contact:        Richard Purdie <rpurdie@rpsys.net>
+Description:
+                Current contrast of this LCD device. Value is between 0 and
+                /sys/class/lcd/<lcd>/max_contrast.
+
+What:           /sys/class/lcd/<lcd>/max_contrast
+Date:           April 2005
+KernelVersion:  2.6.12
+Contact:        Richard Purdie <rpurdie@rpsys.net>
+Description:
+                Maximum contrast for this LCD device.