First slice of drm-misc-next for 4.12:
Core/subsystem-wide:
- link status core patch from Manasi, for signalling link train fail
to userspace. I also had the i915 patch in here, but that had a
small buglet in our CI, so reverted.
- more debugfs_remove removal from Noralf, almost there now (Noralf
said he'll try to follow up with the stragglers).
- drm todo moved into kerneldoc, for better visibility (see
Documentation/gpu/todo.rst), lots of starter tasks in there.
- devm_ of helpers + use it in sti (from Ben Gaignard, acked by Rob
Herring)
- extended framebuffer fbdev support (for fbdev flipping), and vblank
wait ioctl fbdev support (Maxime Ripard)
- misc small things all over, as usual
- add vblank callbacks to drm_crtc_funcs, plus make lots of good use
of this to simplify drivers (Shawn Guo)
- new atomic iterator macros to unconfuse old vs. new state
Small drivers:
- vc4 improvements from Eric
- vc4 kerneldocs (Eric)!
- tons of improvements for dw-mipi-dsi in rockchip from John Keeping
and Chris Zhong.
- MAINTAINERS entries for drivers managed in drm-misc. It's not yet
official, still an experiment, but definitely not complete fail and
better to avoid confusion. We kinda screwed that up with drm-misc a
bit when we started committers last year.
- qxl atomic conversion (Gabriel Krisman)
- bunch of virtual driver polish (qxl, virgl, ...)
- misc tiny patches all over
This is the first time we've done the same merge-window blackout for
drm-misc as we've done for drm-intel for ages, hence why we have a
_lot_ of stuff queued already. But it's still only half of drm-intel
(room to grow!), and the drivers in drm-misc experiment seems to work
at least insofar as that you also get lots of driver updates here
alredy.
* tag 'drm-misc-next-2017-03-06' of git://anongit.freedesktop.org/git/drm-misc: (141 commits)
drm/vc4: Fix OOPSes from trying to cache a partially constructed BO.
drm/vc4: Fulfill user BO creation requests from the kernel BO cache.
Revert "drm/i915: Implement Link Rate fallback on Link training failure"
drm/fb-helper: implement ioctl FBIO_WAITFORVSYNC
drm: Update drm_fbdev_cma_init documentation
drm/rockchip/dsi: add dw-mipi power domain support
drm/rockchip/dsi: fix insufficient bandwidth of some panel
dt-bindings: add power domain node for dw-mipi-rockchip
drm/rockchip/dsi: remove mode_valid function
drm/rockchip/dsi: dw-mipi: correct the coding style
drm/rockchip/dsi: dw-mipi: support RK3399 mipi dsi
dt-bindings: add rk3399 support for dw-mipi-rockchip
drm/rockchip: dw-mipi-dsi: add reset control
drm/rockchip: dw-mipi-dsi: support non-burst modes
drm/rockchip: dw-mipi-dsi: defer probe if panel is not loaded
drm/rockchip: vop: test for P{H,V}SYNC
drm/rockchip: dw-mipi-dsi: use positive check for N{H, V}SYNC
drm/rockchip: dw-mipi-dsi: use specific poll helper
drm/rockchip: dw-mipi-dsi: improve PLL configuration
drm/rockchip: dw-mipi-dsi: properly configure PHY timing
...
Fixed the following style issues
drivers/gpu/vga/vga_switcheroo.c:98: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:99: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:102: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:103: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:129: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:135: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:217: WARNING: line over 80 characters
drivers/gpu/vga/vga_switcheroo.c:218: WARNING: line over 80 characters
drivers/gpu/vga/vga_switcheroo.c:308: WARNING: please, no space before tabs
drivers/gpu/vga/vga_switcheroo.c:340: WARNING: line over 80 characters
drivers/gpu/vga/vga_switcheroo.c:1087: WARNING: Block comments use * on subsequent lines
drivers/gpu/vga/vga_switcheroo.c:1087: WARNING: Block comments use a trailing */ on a separate line
Signed-off-by: Joan Jani <igiann@hotmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/HE1PR1001MB1148F38207BC31C860FAF06DC9560@HE1PR1001MB1148.EURPRD10.PROD.OUTLOOK.COM
We now pass the device to the debug messages, but on non-x86,
this is an invalid pointer in vga_arb_device_init:
drivers/gpu/vga/vgaarb.c: In function 'vga_arb_device_init':
drivers/gpu/vga/vgaarb.c:1467:4: error: 'dev' may be used uninitialized in this function [-Werror=maybe-uninitialized]
This moves the initialization of the dev pointer outside of the
architecture #ifdef.
Fixes: a75d68f621 ("vgaarb: Use dev_printk() when possible")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161122143445.1896558-1-arnd@arndb.de
Use dev_printk() when possible. This makes messages more consistent with
other device-related messages and, in some cases, adds useful information.
This changes messages like this:
vgaarb: failed to allocate pci device
vgaarb: setting as boot device: PCI:0000:01:00.0
vgaarb: device added: PCI:0000:01:00.0,decodes=io+mem,owns=io+mem,locks=none
vgaarb: bridge control possible 0000:01:00.0
to this:
pci 0000:01:00.0: vgaarb: failed to allocate VGA arbiter data
pci 0000:01:00.0: vgaarb: setting as boot VGA device
pci 0000:01:00.0: vgaarb: VGA device added: decodes=io+mem,owns=io+mem,locks=none
pci 0000:01:00.0: vgaarb: bridge control possible
No functional change intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161117174758.16810.67625.stgit@bhelgaas-glaptop.roam.corp.google.com
Daniel Vetter pointed out that vga_switcheroo_client_probe_defer() could
be needed by audio clients as well. To avoid mistakes when someone adds
conditions for these in the future, constrain the single existing
condition to VGA clients by checking for PCI_BASE_CLASS_DISPLAY. This
encompasses both PCI_CLASS_DISPLAY_VGA as well as PCI_CLASS_DISPLAY_3D,
which is used by some Nvidia Optimus GPUs.
Any future checks for audio clients should then be constrained to
PCI_BASE_CLASS_MULTIMEDIA.
v6: Spun out from commit introducing vga_switcheroo_client_probe_defer()
to keep it a pure refactoring change. (Emil Velikov, Jani Nikula)
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/358d58490eb9dda5f270d844b0dce511a2a20828.1464685538.git.lukas@wunner.de
So far we've got one condition when DRM drivers need to defer probing
on a dual GPU system and it's coded separately into each of the relevant
drivers. As suggested by Daniel Vetter, deduplicate that code in the
drivers and move it to a new vga_switcheroo helper. This yields better
encapsulation of concepts and lets us add further checks in a central
place. (The existing check pertains to pre-retina MacBook Pros and an
additional check is expected to be needed for retinas.)
One might be tempted to check deferred probing conditions in
vga_switcheroo_register_client(), but this is usually called fairly late
during driver load. The GPU is fully brought up and ready for switching
at that point. On boot the ->probe hook is potentially called dozens of
times until it finally succeeds, and each time we'd repeat bringup and
teardown of the GPU, lengthening boot time considerably and cluttering
logfiles. A separate helper is therefore needed which can be called
right at the beginning of the ->probe hook.
Note that amdgpu currently does not call this helper as the AMD GPUs
built into MacBook Pros are only supported by radeon so far.
v2: This helper could eventually be used by audio clients as well,
so rephrase kerneldoc to refer to "client" instead of "GPU"
and move the single existing check in an if block specific
to PCI_CLASS_DISPLAY_VGA devices. Move documentation on
that check from kerneldoc to a comment. (Daniel Vetter)
v3: Mandate in kerneldoc that registration of client shall only
happen after calling this helper. (Daniel Vetter)
v4: Rebase on 412c8f7de0 ("drm/radeon: Return -EPROBE_DEFER when
amdkfd not loaded")
v5: Some Optimus GPUs use PCI_CLASS_DISPLAY_3D, make sure those are
matched as well. (Emil Velikov)
v6: The if-condition referring to PCI_BASE_CLASS_DISPLAY may be
considered a functional change. Move to a separate commit to
keep this a pure refactoring change. (Emil Velikov, Jani Nikula)
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/575885fd440c2b13c3f19ddf44360cfbbff35f50.1464685538.git.lukas@wunner.de
Originally by Seth Forshee <seth.forshee@canonical.com>, 2012-10-04:
During graphics driver initialization it's useful to be able to mux
only the DDC to the inactive client in order to read the EDID. Add
a switch_ddc callback to allow capable handlers to provide this
functionality, and add vga_switcheroo_switch_ddc() to allow DRM
to mux only the DDC.
Modified by Dave Airlie <airlied@gmail.com>, 2012-12-22:
I can't figure out why I didn't like this, but I rewrote this [...]
to lock/unlock the ddc lines [...]. I think I'd prefer something
like that otherwise the interface got really ugly.
Modified by Lukas Wunner <lukas@wunner.de>, 2015-04 - 2015-10:
Change semantics of ->switch_ddc handler callback to return previous
DDC owner. Original version tried to determine previous DDC owner
with find_active_client() but this fails if the inactive client
registers before the active client.
Don't lock vgasr_mutex in _lock_ddc() / _unlock_ddc(), it can cause
deadlocks because (a) during switch (with vgasr_mutex already held),
GPU is woken and probes its outputs, tries to re-acquire vgasr_mutex
to lock DDC lines; (b) Likewise during switch, GPU is suspended and
calls cancel_delayed_work_sync() to stop output polling, if poll
task is running at this moment we may wait forever for it to finish.
Instead, lock mux_hw_lock when unregistering the handler because
the only reason why we'd want to lock vgasr_mutex in _lock_ddc() /
_unlock_ddc() is to block the handler from disappearing while DDC
lines are switched.
Also acquire mux_hw_lock in stage2 to avoid race condition where
reading the EDID and switching happens simultaneously. Likewise on
MIGD / MDIS commands and on runtime suspend.
v2.1: Overhaul locking, squash commits (Daniel Vetter)
v2.2: Readability improvements (Thierry Reding)
v2.3: Overhaul locking once more
v2.4: Retain semantics of ->switchto handler callback to switch all
pins, including DDC (Daniel Vetter)
v5: Rename ddc_lock to mux_hw_lock: Since we acquire this both
when calling ->switch_ddc and ->switchto, it protects not just
access to the DDC lines but to the mux in general. This is in
line with the DRM convention to use low-level locks to avoid
concurrent hw access (e.g. i2c, dp_aux) which are often called
hw_lock (Daniel Vetter)
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115
Tested-by: Lukas Wunner <lukas@wunner.de>
[MBP 9,1 2012 intel IVB + nvidia GK107 pre-retina 15"]
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/e81ae9722b84c5ed591805fee3ea6dbf5dc6c4b3.1452525860.git.lukas@wunner.de
Allow handlers to declare their capabilities and allow clients to
obtain that information. So far we have these use cases:
* If the handler is able to switch DDC separately, clients need to
probe EDID with drm_get_edid_switcheroo(). We should allow them
to detect a capable handler to ensure this function only gets
called when needed.
* Likewise if the handler is unable to switch AUX separately, the active
client needs to communicate link training parameters to the inactive
client, which may then skip the AUX handshake and set up its output
with these pre-calibrated values (DisplayPort specification v1.1a,
section 2.5.3.3). Clients need a way to recognize such a situation.
The flags for the radeon_atpx_handler and amdgpu_atpx_handler are
initially set to 0, this can later on be amended with
handler_flags |= VGA_SWITCHEROO_CAN_SWITCH_DDC;
when a ->switch_ddc callback is added.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115
Tested-by: Lukas Wunner <lukas@wunner.de>
[MBP 9,1 2012 intel IVB + nvidia GK107 pre-retina 15"]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/2b0d93ed6e511ca09e95e45e0b35627f330fabce.1452525860.git.lukas@wunner.de
Pull more power management and ACPI updates from Rafael Wysocki:
"This includes fixes on top of the previous batch of PM+ACPI updates
and some new material as well.
From the new material perspective the most significant are the driver
core changes that should allow USB devices to stay suspended over
system suspend/resume cycles if they have been runtime-suspended
already beforehand. Apart from that, ACPICA is updated to upstream
revision 20160108 (cosmetic mostly, but including one fixup on top of
the previous ACPICA update) and there are some devfreq updates the
didn't make it before (due to timing).
A few recent regressions are fixed, most importantly in the cpuidle
menu governor and in the ACPI backlight driver and some x86 platform
drivers depending on it.
Some more bugs are fixed and cleanups are made on top of that.
Specifics:
- Modify the driver core and the USB subsystem to allow USB devices
to stay suspended over system suspend/resume cycles if they have
been runtime-suspended already beforehand and fix some bugs on top
of these changes (Tomeu Vizoso, Rafael Wysocki).
- Update ACPICA to upstream revision 20160108, including updates of
the ACPICA's copyright notices, a code fixup resulting from a
regression fix that was necessary in the upstream code only (the
regression fixed by it has never been present in Linux) and a
compiler warning fix (Bob Moore, Lv Zheng).
- Fix a recent regression in the cpuidle menu governor that broke it
on practically all architectures other than x86 and make a couple
of optimizations on top of that fix (Rafael Wysocki).
- Clean up the selection of cpuidle governors depending on whether or
not the kernel is configured for tickless systems (Jean Delvare).
- Revert a recent commit that introduced a regression in the ACPI
backlight driver, address the problem it attempted to fix in a
different way and revert one more cosmetic change depending on the
problematic commit (Hans de Goede).
- Add two more ACPI backlight quirks (Hans de Goede).
- Fix a few minor problems in the core devfreq code, clean it up a
bit and update the MAINTAINERS information related to it (Chanwoo
Choi, MyungJoo Ham).
- Improve an error message in the ACPI fan driver (Andy Lutomirski).
- Fix a recent build regression in the cpupower tool (Shreyas
Prabhu)"
* tag 'pm+acpi-4.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits)
cpuidle: menu: Avoid pointless checks in menu_select()
sched / idle: Drop default_idle_call() fallback from call_cpuidle()
cpupower: Fix build error in cpufreq-info
cpuidle: Don't enable all governors by default
cpuidle: Default to ladder governor on ticking systems
time: nohz: Expose tick_nohz_enabled
ACPICA: Update version to 20160108
ACPICA: Silence a -Wbad-function-cast warning when acpi_uintptr_t is 'uintptr_t'
ACPICA: Additional 2016 copyright changes
ACPICA: Reduce regression fix divergence from upstream ACPICA
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Satellite R830
ACPI / video: Revert "thinkpad_acpi: Use acpi_video_handles_brightness_key_presses()"
ACPI / video: Document acpi_video_handles_brightness_key_presses() a bit
ACPI / video: Fix using an uninitialized mutex / list_head in acpi_video_handles_brightness_key_presses()
ACPI / video: Revert "ACPI / video: driver must be registered before checking for keypresses"
ACPI / fan: Improve acpi_device_update_power error message
ACPI / video: Add disable_backlight_sysfs_if quirk for the Toshiba Portege R700
cpuidle: menu: Fix menu_select() for CPUIDLE_DRIVER_STATE_START == 0
MAINTAINERS: Add devfreq-event entry
MAINTAINERS: Add missing git repository and directory for devfreq
...
* pm-core:
driver core: Avoid NULL pointer dereferences in device_is_bound()
platform: Do not detach from PM domains on shutdown
USB / PM: Allow USB devices to remain runtime-suspended when sleeping
PM / sleep: Go direct_complete if driver has no callbacks
PM / Domains: add setter for dev.pm_domain
device core: add device_is_bound()
Pull drm updates from Dave Airlie:
"This is the main drm pull request for 4.5. I don't think I've missed
anything too major, I'm mostly back at work now but I'll probably get
some sleep in 5 years time.
Summary:
New drivers:
- etnaviv:
GPU driver for the 3D core on the Vivante core used in numerous
ARM boards.
Highlights:
Core:
- Atomic suspend/resume helpers
- Move the headers to using userspace friendlier types.
- Documentation updates
- Lots of struct_mutex removal.
- Bunch of DP MST fixes from AMD.
Panel:
- More DSI helpers
- Support for some new basic panels
i915:
- Basic Kabylake support
- DP link training and detect code refactoring
- fbc/psr fixes
- FIFO underrun fixes
- SDE interrupt handling fixes
- dma-buf/fence support in pageflip path.
- GPU side for MST audio support
radeon/amdgpu:
- Drop UMS support
- GPUVM/Scheduler optimisations
- Initial Powerplay support for Tonga/Fiji/CZ/ST
- ACP audio prerequisites
nouveau:
- GK20a instmem improvements
- PCIE link speed change support
msm:
- DSI support for msm8960/apq8064
tegra:
- Host1X support for Tegra210 SoC
vc4:
- 3D acceleration support
armada:
- Get rid of struct mutex
tda998x:
- Atomic modesetting support
- TMDS clock limitations
omapdrm:
- Atomic modesetting support
- improved TILER performance
rockchip:
- RK3036 VOP support
- Atomic modesetting support
- Synopsys DW MIPI DSI support
exynos:
- Runtime PM support
- of_graph binding for DP panels
- Cleanup of IPP code
- Configurable plane support
- Kernel panic fixes at release time"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (711 commits)
drm/fb_cma_helper: Remove implicit call to disable_unused_functions
drm/amdgpu: add missing irq.h include
drm/vmwgfx: Fix a width / pitch mismatch on framebuffer updates
drm/vmwgfx: Fix an incorrect lock check
drm: nouveau: fix nouveau_debugfs_init prototype
drm/nouveau/pci: fix check in nvkm_pcie_set_link
drm/amdgpu: validate duplicates first
drm/amdgpu: move VM page tables to the LRU end on CS v2
drm/ttm: add ttm_bo_move_to_lru_tail function v2
drm/ttm: fix adding foreign BOs to the swap LRU
drm/ttm: fix adding foreign BOs to the LRU during init v2
drm/radeon: use kobj_to_dev()
drm/amdgpu: use kobj_to_dev()
drm/amdgpu/cz: force vce clocks when sclks are forced
drm/amdgpu/cz: force uvd clocks when sclks are forced
drm/amdgpu/cz: add code to enable forcing VCE clocks
drm/amdgpu/cz: add code to enable forcing UVD clocks
drm/amdgpu: fix lost sync_to if scheduler is enabled.
drm/amd/powerplay: fix static checker warning for return meaningless value.
drm/sysfs: use kobj_to_dev()
...
Since your main drm-next pull isn't out of the door yet I figured I might
as well flush out drm-misc instead of delaying for 4.6. It's really just
random stuff all over, biggest thing probably connector_mask tracking from
Maarten.
* tag 'topic/drm-misc-2016-01-17' of git://anongit.freedesktop.org/drm-intel: (24 commits)
drm/fb_cma_helper: Remove implicit call to disable_unused_functions
drm/sysfs: use kobj_to_dev()
drm/i915: Init power domains early in driver load
drm: Do not set connector->encoder in drivers
apple-gmux: Add initial documentation
drm: move MODULE_PARM_DESC to other file
drm/edid: index CEA/HDMI mode tables using the VIC
drm/atomic: Remove drm_atomic_connectors_for_crtc.
drm/i915: Update connector_mask during readout, v2.
drm: Remove opencoded drm_gem_object_release_handle()
drm: Do not set outparam on error during GEM handle allocation
drm/docs: more leftovers from the big vtable documentation pile
drm/atomic-helper: Reject legacy flips on a disabled pipe
drm/atomic: add connector mask to drm_crtc_state.
drm/tegra: Use __drm_atomic_helper_reset_connector for subclassing connector state, v2.
drm/atomic: Add __drm_atomic_helper_connector_reset, v2.
drm/i915: Set connector_state->connector using the helper.
drm: Use a normal idr allocation for the obj->name
drm: Only bump object-reference count when adding first handle
drm: Balance error path for GEM handle allocation
...
Adds a function that sets the pointer to dev_pm_domain in struct device
and that warns if the device has already finished probing. The reason
why we want to enforce that is because in the general case that can
cause problems and also that we can simplify code quite a bit if we can
always assume that.
This patch also changes all current code that directly sets the
dev.pm_domain pointer.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Fix indentation of vga_switcheroo sections in gpu.tmpl.
Change section type of API documentation from "chapter" to "sect1"
so that the individual functions no longer clutter up the ToC.
Group together under a new "API" chapter.
Fix wording "heretoforth" -> "henceforth".
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There are few defects in vga_get() related to signal hadning:
- we shouldn't check for pending signals for TASK_UNINTERRUPTIBLE
case;
- if we found pending signal we must remove ourself from wait queue
and change task state back to running;
- -ERESTARTSYS is more appropriate, I guess.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: stable@vger.kernel.org
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
neither ->release() nor ->poll() can be called unless ->open()
has succeeded on the same struct file, so checking for "has
open() failed" is pointless. What's more, ->poll() doesn't
return -E... - it always returns a bitmap of POLL... values,
so the dead code in that one had been actively bogus.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
hda_intel.c:azx_probe() defers initialization of an audio controller
on the discrete GPU if the GPU is powered off. The power state of the
GPU is determined by calling vga_switcheroo_get_client_state().
vga_switcheroo_get_client_state() returns VGA_SWITCHEROO_INIT if
vga_switcheroo is not enabled, i.e. if no second GPU or no handler
has registered.
This can go wrong in the following scenario:
- Driver for the integrated GPU is not loaded.
- Driver for the discrete GPU registers with vga_switcheroo, uses driver
power control to power down the GPU, handler cuts power to the GPU.
- Driver for the audio controller gets loaded after the GPU was powered
down, calls vga_switcheroo_get_client_state() which returns
VGA_SWITCHEROO_INIT instead of VGA_SWITCHEROO_OFF.
- Consequence: azx_probe() tries to initialize the audio controller even
though the GPU is powered down.
The power state VGA_SWITCHEROO_INIT was introduced by c8e9cf7bb2
("vga_switcheroo: Add a helper function to get the client state").
It is not apparent what its benefit might be. The idea seems to
be to initialize the audio controller even if the power state is
VGA_SWITCHEROO_OFF (were vga_switcheroo enabled), but as shown
above this can fail.
Drop VGA_SWITCHEROO_INIT to solve this.
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Dave Airlie
Ingo Molnar
Joan Jani
Arnd Bergmann
Bjorn Helgaas
Dmitry Vyukov
Daniel Vetter
Lukas Wunner
Linus Torvalds
Rafael J. Wysocki
Tomeu Vizoso
Al Viro
Kirill A. Shutemov