linux/include
Rafael J. Wysocki f244d8b623 ACPIPHP / radeon / nouveau: Fix VGA switcheroo problem related to hotplug
The changes in the ACPI-based PCI hotplug (ACPIPHP) subsystem made
during the 3.12 development cycle uncovered a problem with VGA
switcheroo that on some systems, when the device-specific method
(ATPX in the radeon case, _DSM in the nouveau case) is used to turn
off the discrete graphics, the BIOS generates ACPI hotplug events for
that device and those events cause ACPIPHP to attempt to remove the
device from the system (they are events for a device that was present
previously and is not present any more, so that's what should be done
according to the spec).  Then, the system stops functioning correctly.

Since the hotplug events in question were simply silently ignored
previously, the least intrusive way to address that problem is to
make ACPIPHP ignore them again.  For this purpose, introduce a new
ACPI device flag, no_hotplug, and modify ACPIPHP to ignore hotplug
events for PCI devices whose ACPI companions have that flag set.
Next, make the radeon and nouveau switcheroo detection code set the
no_hotplug flag for the discrete graphics' ACPI companion.

Fixes: bbd34fcdd1 (ACPI / hotplug / PCI: Register all devices under the given bridge)
References: https://bugzilla.kernel.org/show_bug.cgi?id=61891
References: https://bugzilla.kernel.org/show_bug.cgi?id=64891
Reported-and-tested-by: Mike Lothian <mike@fireburn.co.uk>
Reported-and-tested-by: <madcatx@atlas.cz>
Reported-and-tested-by: Joaquín Aramendía <samsagax@gmail.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.12+ <stable@vger.kernel.org> # 3.12+
2013-12-31 13:39:42 +01:00
..
acpi ACPIPHP / radeon / nouveau: Fix VGA switcheroo problem related to hotplug 2013-12-31 13:39:42 +01:00
asm-generic Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-15 16:47:22 -08:00
clocksource
crypto keys: change asymmetric keys to use common hash definitions 2013-10-25 17:15:18 -04:00
drm Merge branch 'ttm-fixes-3.13' of git://people.freedesktop.org/~thomash/linux into drm-fixes 2013-11-21 18:46:56 +10:00
dt-bindings For the 3.13 merge window we have a couple of new drivers for the AMS 2013-11-15 16:37:40 -08:00
keys
kvm
linux PCI updates for v3.13: 2013-11-22 10:53:47 -08:00
math-emu
media Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2013-11-18 15:50:07 -08:00
memory
misc
net genetlink: fix genl_set_err() group ID 2013-11-21 13:09:43 -05:00
pcmcia
ras
rdma Merge branches 'cma', 'cxgb4', 'flowsteer', 'ipoib', 'misc', 'mlx4', 'mlx5', 'nes', 'ocrdma', 'qib' and 'srp' into for-next 2013-11-17 08:22:19 -08:00
rxrpc
scsi Main batch of InfiniBand/RDMA changes for 3.13: 2013-11-18 15:36:04 -08:00
sound Merge remote-tracking branch 'asoc/topic/twl4030' into asoc-next 2013-11-08 10:43:40 +00:00
target target_core_alua: Store supported ALUA states 2013-11-20 11:26:37 -08:00
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2013-11-22 08:38:55 -08:00
uapi Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-11-22 10:56:11 -08:00
video fbdev changes for 3.13 2013-11-14 14:44:20 +09:00
xen Features: 2013-11-15 13:34:37 +09:00
Kbuild