linux-stable/include
Clemens Ladisch ab69a4904b ALSA: pcm: support for period wakeup disabling
This patch allows to disable period interrupts which are
not needed when the application relies on a system timer
to wake-up and refill the ring buffer. The behavior of
the driver is left unchanged, and interrupts are only
disabled if the application requests this configuration.
The behavior in case of underruns is slightly different,
instead of being detected during the period interrupts the
underruns are detected when the application calls
snd_pcm_update_avail, which in turns forces a refresh of the
hw pointer and shows the buffer is empty.

More specifically this patch makes a lot of sense when
PulseAudio relies on timer-based scheduling to access audio
devices such as HDAudio or Intel SST. Disabling interrupts
removes two unwanted wake-ups due to period elapsed events
in low-power playback modes. It also simplifies PulseAudio
voice modules used for speech calls.

To quote Lennart "This patch looks very interesting and
desirable. This is something have long been waiting for."

Support for this in hardware drivers is optional.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@intel.com>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-11-22 08:13:16 +01:00
..
acpi Merge branch 'misc' into release 2010-10-26 14:51:00 -04:00
asm-generic audit: make link()/linkat() match "attribute change" predicate 2010-10-30 08:45:43 -04:00
crypto Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-10-24 13:41:39 -07:00
drm Merge remote branch 'intel/drm-intel-next' of ../drm-next into drm-core-next 2010-10-26 09:23:22 +10:00
keys
linux Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6 2010-11-01 07:50:43 -04:00
math-emu
media Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2010-10-28 09:35:11 -07:00
mtd mtd: Define MLC Flash as a different flash type 2010-10-25 00:50:20 +01:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2010-10-29 14:17:12 -07:00
pcmcia pcmcia: IOCARD is also required for using IRQs 2010-10-22 08:46:36 +02:00
rdma IB/core: Add VLAN support for IBoE 2010-10-25 10:20:39 -07:00
rxrpc
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2010-10-31 20:43:12 -04:00
sound ALSA: pcm: support for period wakeup disabling 2010-11-22 08:13:16 +01:00
trace Merge branch 'next' into upstream-merge 2010-10-27 23:44:47 -04:00
video Merge master.kernel.org:/pub/scm/linux/kernel/git/lethal/genesis-2.6 into devel-stable 2010-10-28 20:14:38 +01:00
xen Merge branch 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen 2010-10-28 17:11:17 -07:00
Kbuild