linux-stable/sound
Mengdong Lin 795614dde4 ALSA: hda - divide controller and codec dependency on i915 gfx power well
This patch can improve power saving for Intel platforms on which only the
display audio codec is in the shared i915 power well:

- Add a flag "need_i915_power" to indicate whether the controller needs the
  i915 power well.

- The driver will always request the i915 power when probing the controller
  and codecs if AZX_DCAPS_I915_POWERWELL is set (either the controller or a
  codec needs this power).

- If the controller needs the i915 power, the power will be held after probe
  until the controller is runtime suspended or S3. If the controller doesn't
  need the power, the power will be released the after probe, and a codec
  that needs the power can request/release the power via bus link_power ops.

Background:
- For Haswell/Broadwell, which has a separate HD-A controller for display audio,
  both the controller and the display codec are in the i915 power well.

- For Baytrail/Braswell, the display and analog audio share the same HDA
  controller and link, and only the display codec is in the i915 power well.

- For Skylake, the display and analog audio share the same HDA controller but
  use separate links. Only the display codec is in the i915 power well. And in
  legacy mode we take the two links as one. So it can follow Baytrail/Braswell.

Signed-off-by: Mengdong Lin <mengdong.lin@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-04-29 12:27:53 +02:00
..
aoa ALSA: aoa: constify of_device_id array 2015-03-19 12:11:13 +01:00
arm
atmel
core ALSA: ctl: fix to handle several elements added by one operation for userspace element 2015-04-13 10:31:49 +02:00
drivers Merge branch 'for-linus' into for-next 2015-03-09 08:42:00 +01:00
firewire Merge branch 'for-next' into for-linus 2015-04-13 10:23:18 +02:00
hda ALSA: hda - allow a codec to control the link power 2015-04-29 12:27:52 +02:00
i2c ALSA: ak411x: simplify snd_ak4113_create() a bit 2015-03-23 13:58:59 +01:00
isa sound: Deparenthesize negative error returns 2015-03-24 11:41:37 +01:00
mips ALSA: au1x00: fix error return code 2015-04-05 18:04:27 +02:00
oss sound: Deparenthesize negative error returns 2015-03-24 11:41:37 +01:00
parisc
pci ALSA: hda - divide controller and codec dependency on i915 gfx power well 2015-04-29 12:27:53 +02:00
pcmcia
ppc
sh
soc Merge remote-tracking branches 'asoc/topic/wm2200', 'asoc/topic/wm5100', 'asoc/topic/wm8731', 'asoc/topic/wm8804' and 'asoc/topic/wm8996' into asoc-next 2015-04-12 19:49:22 +01:00
sparc
spi
synth
usb Merge branch 'for-next' into for-linus 2015-04-13 10:23:18 +02:00
ac97_bus.c
Kconfig ALSA: hda - Make snd_hda_bus_type public 2015-03-23 13:15:51 +01:00
last.c
Makefile ALSA: hda - Make snd_hda_bus_type public 2015-03-23 13:15:51 +01:00
sound_core.c
sound_firmware.c