linux_dsm_epyc7002/sound
Ville Syrjälä 183c00350c drm/i915: Fix runtime PM for LPE audio
Not calling pm_runtime_enable() means that runtime PM can't be
enabled at all via sysfs. So we definitely need to call it
from somewhere.

Calling it from the driver seems like a bad idea because it
would have to be paired with a pm_runtime_disable() at driver
unload time, otherwise the core gets upset. Also if there's
no LPE audio driver loaded then we couldn't runtime suspend
i915 either.

So it looks like a better plan is to call it from i915 when
we register the platform device. That seems to match how
pci generally does things. I cargo culted the
pm_runtime_forbid() and pm_runtime_set_active() calls from
pci as well.

The exposed runtime PM API is massive an thorougly misleading, so
I don't actually know if this is how you're supposed to use the API
or not. But it seems to work. I can now runtime suspend i915 again
with or without the LPE audio driver loaded, and reloading the
LPE audio driver also seems to work.

Note that powertop won't auto-tune runtime PM for platform devices,
which is a little annoying. So I'm not sure that leaving runtime
PM in "on" mode by default is the best choice here. But I've left
it like that for now at least.

Also remove the comment about there not being much benefit from
LPE audio runtime PM. Not allowing runtime PM blocks i915 runtime
PM, which will also block s0ix, and that could have a measurable
impact on power consumption.

Cc: stable@vger.kernel.org
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Fixes: 0b6b524f39 ("ALSA: x86: Don't enable runtime PM as default")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170427160231.13337-2-ville.syrjala@linux.intel.com
Reviewed-by: Takashi Iwai <tiwai@suse.de>
2017-05-03 16:18:23 +03:00
..
aoa powerpc updates for 4.9 2016-10-07 20:19:31 -07:00
arm
atmel
core ALSA: seq: Fix race during FIFO resize 2017-03-24 17:11:00 +01:00
drivers ALSA: drivers: Constify snd_rawmidi_ops 2017-01-12 12:50:06 +01:00
firewire sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h> 2017-03-02 08:42:32 +01:00
hda Linux 4.10-rc1 2017-01-24 16:24:18 +00:00
i2c
isa sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h> 2017-03-02 08:42:32 +01:00
mips ALSA: mips: avoid potential uninitialized variable use 2017-01-16 14:33:42 +01:00
oss sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h> 2017-03-02 08:42:32 +01:00
parisc
pci ALSA: hda - fix a problem for lineout on a Dell AIO machine 2017-03-31 10:58:26 +02:00
pcmcia lib/vsprintf.c: remove %Z support 2017-02-27 18:43:47 -08:00
ppc scripts/spelling.txt: add "followings" pattern and fix typo instances 2017-02-27 18:43:47 -08:00
sh ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
soc ASoC: Fixes for v4.11 2017-03-30 20:03:25 +02:00
sparc dbri: move dereference after check for NULL 2016-12-06 12:18:22 -05:00
spi
synth ALSA: synth: use designated initializers 2016-12-28 16:06:16 +01:00
usb mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
x86 drm/i915: Fix runtime PM for LPE audio 2017-05-03 16:18:23 +03:00
ac97_bus.c
Kconfig ALSA: add Intel HDMI LPE audio driver for BYT/CHT-T 2017-01-25 14:23:46 +01:00
last.c
Makefile ALSA: add Intel HDMI LPE audio driver for BYT/CHT-T 2017-01-25 14:23:46 +01:00
sound_core.c