ALSA: hda/i915 - fix list corruption with concurrent probes

Current hdac_i915 uses a static completion instance to wait
for i915 driver to complete the component bind.

This design is not safe if multiple HDA controllers are active and
communicating with different i915 instances, and can lead to list
corruption and failed audio driver probe.

Fix the design by moving completion mechanism to common acomp
code and remove the related code from hdac_i915.

Fixes: 7b882fe3e3e8 ("ALSA: hda - handle multiple i915 device instances")
Co-developed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20201006161722.500256-1-kai.vehmanen@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: hda: Update kernel-doc function parameter descriptions

Make W=1 throws a lot of warnings, with multiple misalignments between
function params and their descriptions.

Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200113205638.27338-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: hda: Fix racy display power access

snd_hdac_display_power() doesn't handle the concurrent calls carefully
enough, and it may lead to the doubly get_power or put_power calls,
when a runtime PM and an async work get called in racy way.

This patch addresses it by reusing the bus->lock mutex that has been
used for protecting the link state change in ext bus code, so that it
can protect against racy display state changes. The initialization of
bus->lock was moved from snd_hdac_ext_bus_init() to
snd_hdac_bus_init() as well accordingly.

Testcase: igt/i915_pm_rpm/module-reload #glk-dsi
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: hda: Fix racy display power access

snd_hdac_display_power() doesn't handle the concurrent calls carefully
enough, and it may lead to the doubly get_power or put_power calls,
when a runtime PM and an async work get called in racy way.

This patch addresses it by reusing the bus->lock mutex that has been
used for protecting the link state change in ext bus code, so that it
can protect against racy display state changes. The initialization of
bus->lock was moved from snd_hdac_ext_bus_init() to
snd_hdac_bus_init() as well accordingly.

Testcase: igt/i915_pm_rpm/module-reload #glk-dsi
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/s5h8swiunph.wl-tiwai@suse.de

snd/hda, drm/i915: Track the display_power_status using a cookie

drm/i915 is tracking all wakeref owners with a cookie in order to
identify leaks. To that end, each rpm acquisition ops->get_power is
assigned a cookie which should be passed to ops->put_power to signify
its release (and removal from the list of wakeref owners). As snd/hda is
already using a bool to track current status of display_power extending
that to an unsigned long to hold the boolean cookie is a trivial
extension, and will quell all doubt that snd/hda is the cause of the
device runtime pm leaks.

v2: Keep using the power abstraction for local wakeref tracking.
v3: BUILD_BUG_ON impedance mismatch

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jani Nikula <jani.nikula@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190213152109.16997-1-chris@chris-wilson.co.uk

i915/snd_hdac: I915 subcomponent for the snd_hdac

Since we need multiple components for I915 for different purposes
(Audio & Mei_hdcp), we adopt the subcomponents methodology introduced
by the previous patch (mentioned below).

Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Mon Jan 28 17:08:20 2019 +0530

components: multiple components for a device

Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by-by: Ramalingam C <ramalinagm.c@intel.com> (commit message)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> (code)
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Russell King <rmk+kernel@arm.linux.org.uk>
cc: Rafael J. Wysocki <rafael@kernel.org>
cc: Jaroslav Kysela <perex@perex.cz>
cc: Takashi Iwai <tiwai@suse.com>
cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
cc: Jani Nikula <jani.nikula@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207232759.14553-4-daniel.vetter@ffwll.ch

ALSA: hda: Make snd_hdac_display_power() void function

After the recent refactoring, snd_hdac_display_power() doesn't return
any error, hence it can be defined to return void.
This makes many error checks redundant and allows us to reduce them
gracefully.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: hda: Refactor display power management

The current HD-audio code manages the DRM audio power via too complex
redirections, and this seems even still unbalanced in a corner case as
Intel DRM CI has been intermittently reporting. This patch is a big
surgery for addressing the complexity and the possible unbalance.

Basically the patch changes the display PM in the following ways:

- Both HD-audio controller and codec drivers call a single helper,
snd_hdac_display_power(). (Formerly, the display power control from
a codec was done indirectly via link_power bus ops.)

- snd_hdac_display_power() receives the codec address index. For
turning on/off from the controller, pass HDA_CODEC_IDX_CONTROLLER.

- snd_hdac_display_power() doesn't manage refcounts any longer, but
keeps the power status in bitmap. If any of controller or codecs is
turned on, the function updates the DRM power state via get_power()
or put_power().

Also this refactor allows us more cleanup:

- The link_power bus ops is dropped, so there is no longer indirect
management, as mentioned in the above.

- hdac_device link_power_control flag is moved to hda_codec
display_power_control flag, as it's only for HDA legacy.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106525
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: hda: Make audio component support more generic

This is the final step for more generic support of DRM audio
component. The generic audio component code is now moved to its own
file, and the symbols are renamed from snd_hac_i915_* to
snd_hdac_acomp_*, respectively. The generic code is enabled via the
new kconfig, CONFIG_SND_HDA_COMPONENT, while CONFIG_SND_HDA_I915 is
kept as the super-class.

Along with the split, three new callbacks are added to audio_ops:
pin2port is for providing the conversion between the pin number and
the widget id, and master_bind/master_unbin are called at binding /
unbinding the master component, respectively. All these are optional,
but used in i915 implementation and also other later implementations.

A note about the new snd_hdac_acomp_init() function: there is a slight
difference between this and the old snd_hdac_i915_init(). The latter
(still) synchronizes with the master component binding, i.e. it
assures that the relevant DRM component gets bound when it returns, or
gives a negative error. Meanwhile the new function doesn't
synchronize but just leaves as is. It's the responsibility by the
caller's side to synchronize, or the caller may accept the
asynchronous binding on the fly.

v1->v2: Fix missing NULL check in master_bind/unbind

Signed-off-by: Takashi Iwai <tiwai@suse.de>