commit 718be4aaf3 upstream.
It turns out that there is a bit in the _CST for Intel FFH C3
that tells the OS if we should be checking BM_STS or not.
Linux has been unconditionally checking BM_STS.
If the chip-set is configured to enable BM_STS,
it can retard or completely prevent entry into
deep C-states -- as illustrated by turbostat:
http://userweb.kernel.org/~lenb/acpi/utils/pmtools/turbostat/
ref: Intel Processor Vendor-Specific ACPI Interface Specification
table 4 "_CST FFH GAS Field Encoding"
Bit 1: Set to 1 if OSPM should use Bus Master avoidance for this C-state
https://bugzilla.kernel.org/show_bug.cgi?id=15886
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Every acpi_device has at least one ID (if there's no _HID or _CID, we
give it a synthetic or default ID). So there's no longer a need to
check whether an ID exists; we can just use it.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We now keep a single list of IDs that includes both the _HID and any
_CIDs. We no longer need to keep track of whether the device has a _CID.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
There's no need to treat _HID and _CID differently. Keeping them in
a single list makes code that uses the IDs a little simpler because it
can just traverse the list rather than checking "do we have a HID?",
"do we have any CIDs?"
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add acpi_bus_get_status_handle() so we can get the status of a namespace
object before building a struct acpi_device.
This removes a use of "device->flags.dynamic_status", a cached indicator of
whether _STA exists. It seems simpler and more reliable to just evaluate
_STA and catch AE_NOT_FOUND errors.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We can identify the root of the ACPI device tree by the fact that it
has no parent. This is simpler than passing around ACPI_BUS_TYPE_SYSTEM
and will help remove special treatment of the device tree root.
Currently, we add the root by hand with ACPI_BUS_TYPE_SYSTEM. If we
traverse the tree treating the root as just another device and use
acpi_get_type(), the root shows up as ACPI_TYPE_DEVICE.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Most uses of the ACPI bus device_type (ACPI_BUS_TYPE_DEVICE,
ACPI_BUS_TYPE_POWER, etc) are during device initialization, but
we do need it later for notify handler installation, since that
is different for fixed hardware devices vs. namespace devices.
This patch saves the device_type in the acpi_device structure,
so we can check that rather than comparing against the _HID string.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel: (57 commits)
drm/i915: Handle ERESTARTSYS during page fault
drm/i915: Warn before mmaping a purgeable buffer.
drm/i915: Track purged state.
drm/i915: Remove eviction debug spam
drm/i915: Immediately discard any backing storage for uneeded objects
drm/i915: Do not mis-classify clean objects as purgeable
drm/i915: Whitespace correction for madv
drm/i915: BUG_ON page refleak during unbind
drm/i915: Search harder for a reusable object
drm/i915: Clean up evict from list.
drm/i915: Add tracepoints
drm/i915: framebuffer compression for GM45+
drm/i915: split display functions by chip type
drm/i915: Skip the sanity checks if the current relocation is valid
drm/i915: Check that the relocation points to within the target
drm/i915: correct FBC update when pipe base update occurs
drm/i915: blacklist Acer AspireOne lid status
ACPI: make ACPI button funcs no-ops if not built in
drm/i915: prevent FIFO calculation overflows on 32 bits with high dotclocks
drm/i915: intel_display.c handle latency variable efficiently
...
Fix up trivial conflicts in drivers/gpu/drm/i915/{i915_dma.c|i915_drv.h}
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (119 commits)
ACPI: don't pass handle for fixed hardware notifications
ACPI: remove null pointer checks in deferred execution path
ACPI: simplify deferred execution path
acerhdf: additional BIOS versions
acerhdf: convert to dev_pm_ops
acerhdf: fix fan control for AOA150 model
thermal: add missing Kconfig dependency
acpi: switch /proc/acpi/{debug_layer,debug_level} to seq_file
hp-wmi: fix rfkill memory leak on unload
ACPI: remove unnecessary #ifdef CONFIG_DMI
ACPI: linux/acpi.h should not include linux/dmi.h
hwmon driver for ACPI 4.0 power meters
topstar-laptop: add new driver for hotkeys support on Topstar N01
thinkpad_acpi: fix rfkill memory leak on unload
thinkpad-acpi: report brightness events when required
thinkpad-acpi: don't poll by default any of the reserved hotkeys
thinkpad-acpi: Fix procfs hotkey reset command
thinkpad-acpi: deprecate hotkey_bios_mask
thinkpad-acpi: hotkey poll fixes
thinkpad-acpi: be more strict when detecting a ThinkPad
...
Yakui pointed out that we don't properly no-op the ACPI button routines
if the button driver isn't built in. This will cause problems if ACPI
is disabled, so provide stub functions in that case.
Reported-by: ykzhao <yakui.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some drivers need to know when a lid event occurs and get the current
status. This can be useful for when a platform firmware clobbers some
hardware state at lid time, and a driver needs to restore things when
the lid is opened again.
Acked-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
The wakeup.prepared flag is used for marking devices that have the
wake-up power already enabled, so that the wake-up power is not
enabled twice in a row for the same device. This assumes, however,
that device wake-up power will only be enabled once, while the device
is being prepared for a system-wide sleep transition, and the second
attempt is made by acpi_enable_wakeup_device_prep().
With the upcoming PCI wake-up rework this assumption will not hold
any more for PCI bridges and the root bridge whose wake-up power
may be enabled as a result of wake-up enable propagation from other
devices (eg. add-on devices that are not associated with any GPEs).
Thus, there may be many attempts to enable wake-up power on a PCI
bridge or the root bridge during a system power state transition
and it's better to replace wakeup.prepared with a reference counter.
Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We can simplify ACPI drivers if we can tell whether a handle is an
ACPI PCI root or not.
Reviewed-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Linux/ACPI core files using internal.h all PREFIX "ACPI: ",
however, not all ACPI drivers use/want it -- and they
should not have to #undef PREFIX to define their own.
Add GPL commment to internal.h while we are there.
This does not change any actual console output,
asside from a whitespace fix.
Signed-off-by: Len Brown <len.brown@intel.com>
