Vendors often ship machines with a choice of integrated or discrete
graphics, and use the same DSDT for both. As a result, the ACPI video
module will locate devices that may not exist on this specific platform.
Attempt to determine whether the device exists or not, and abort the
device creation if it do not exist.
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Some machines seem to need the backlight brightness to be reset on resume.
Add support for doing so to the video module.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Call notifier chain for display/brightness switch events.
The kernel mode graphics driver is interested in this.
Sign-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Kernel mode graphics drivers need this ACPI notifier chaine
so that they can get notified upon hotkey events.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Display switching via ACPI control methods are
not known to work on any platforms.
Further, the X community wants to control the display
switching all by themselves without BIOS/AML involvement.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Introduce new module parameter for brightness control.
"brightness_switch_enabled" is set by default which means
nothing changes upon brightness switch events.
When "brightness_switch_enabled" is cleared via
"echo 0 > /sys/module/video/parameters/brightness_switch_enabled",
ACPI will not try to change the brightness level any more.
Either X will take charge of this or users can change the brightness level
by poking /sys/class/backlight/acpi_videoX/...
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add a default poll idle state with 0 latency. Provides an option to users
to use poll_idle by using 0 as the latency requirement.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Show C1 idle time in /sysfs cpuidle interface. C1 idle time may not
be entirely accurate in all cases. It includes the time spent
in the interrupt handler after wakeup with "hlt" based C1. But, it will
be accurate with "mwait" based C1.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add MWAIT idle for C1 state instead of halt, on platforms that support
C1 state with MWAIT.
Renames cx->space_id to something more appropriate.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Len Brown
Matthew Garrett
Zhang Rui
venkatesh.pallipadi@intel.com