Delay the read of the EC status register until
after the event that caused it occurs -- otherwise
it is possible to read and act on stale status that was
associated with the previous event.
Do this with a perpetually incrementing "event_count" to detect
when a new event occurs and it is safe to read status.
There is no workaround for polling mode -- it is inherently
exposed to reading and acting on stale status, since it
doesn't have an interrupt to tell it the event completed.
http://bugzilla.kernel.org/show_bug.cgi?id=8110
Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
It is useful to know whether your laptop is docked or not,
but it is even more useful to know which docking station it's
docked to. Attached patch adds "uid" file to sysfs.
Tested on Dell Latitude D600 with D/Dock.
Patch is against official 2.6.20 release.
Signed-off-by: Len Brown <len.brown@intel.com>
Correct some of the most obvious spelling and grammar
mistakes in drivers/acpi/video.c (comments and printk output).
Signed-off-by: Julius Volz <juliusrv@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>
IMHO, ACPI disabled due to DMI failure or blacklisted year should be noted,
as is done with other ACPI blacklisting.
This will help people troubleshoot when ACPI isn't working. Status quo is
a mysterious "ACPI Disabled" message without explanation on BIOS that
implements ACPI but not DMI. This is actually fairly common on embedded
x86 boards.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Improve the backlight code to emulate as much as possible the power
management events, as we are unable to really power on or power off the
backlight.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Len Brown <len.brown@intel.com>
This is a workaround to handle a BIOS bug where the
programmer exchanged the name and index fields of
a _PRT entry. Apparently this BIOS error does not
confuse Windows and thus it lurks in the field
on various machines.
boot with "acpi=strict" to disable this workaround
http://bugzilla.kernel.org/show_bug.cgi?id=6859
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
/proc exports _BST in a single file, and _BST is re-evaulated
whenever that file is read.
Sometimes user-space reads this file frequently, and on some
systems _BST takes a long time to evaluate due to a slow EC.
Further, when we move to sysfs, the values returned from _BST
will be in multiple files, and evaluating _BST for each
file read would make matters worse.
Here code is added to support caching the results of _BST.
A new module parameter "update_time" tells how many seconds the
cached _BST should be used before it is re-evaluated.
Currently, update_time defaults to 0, and so the
existing behaviour of re-evaluating on each read retained.
Signed-off-by: Vladimir Lebedev <vladimir.p.lebedev@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Cleanup -- No functional changes.
Battery state is currently exported in a proc "state" file.
Update associated #defines and routines to be consistent.
Signed-off-by: Vladimir Lebedev <vladimir.p.lebedev@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The brightness class core does not update the initial status of the
device's brightness at register time. Do it by ourselves.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Per device data such as brightness belongs to the indivdual device
and should therefore be separate from the the backlight operation
function pointers. This patch splits the two types of data and
allows simplifcation of some code.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Remove uneeded owner field from backlight_properties structure.
Nothing uses it and it is unlikely that it will ever be used. The
backlight class uses other means to ensure that nothing references
unloaded code.
Based on a patch from Dmitry Torokhov <dtor@insightbb.com>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>