ALSA: hda - Manage power well properly for resume
BugLink: http://bugs.launchpad.net/bugs/1621113 commit a52ff34e upstream. For SKL and later Intel chips, we control the power well per codec basis via link_power callback since the commit [03b135ce: ALSA: hda - remove dependency on i915 power well for SKL]. However, there are a few exceptional cases where the gfx registers are accessed from the audio driver: namely the wakeup override bit toggling at (both system and runtime) resume. This seems causing a kernel warning when accessed during the power well down (and likely resulting in the bogus register accesses). This patch puts the proper power up / down sequence around the resume code so that the wakeup bit is fiddled properly while the power is up. (The other callback, sync_audio_rate, is used only in the PCM callback, so it's guaranteed in the power-on.) Also, by this proper power up/down, the instantaneous flip of wakeup bit in the resume callback that was introduced by the commit [033ea349: ALSA: hda - Fix Skylake codec timeout] becomes superfluous, as snd_hdac_display_power() already does it. So we can clean it up together. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96214 Fixes: 03b135ce ('ALSA: hda - remove dependency on i915 power well for SKL') Cc: <stable@vger.kernel.org> # v4.2+ Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com>
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