linux-sg2042/sound
Takashi Iwai f8ff2f28ba ALSA: pcm: Skip ack callback without actual appl_ptr update
We call ack callback whenever appl_ptr gets updated via
pcm_lib_apply_appl_ptr().  There are various code paths to call this
function.  A part of them are for read/write/forward/rewind, where the
appl_ptr is always changed and thus the call of ack is mandatory.
OTOH, another part of code paths are from the explicit user call,
e.g. via SYNC_PTR ioctl.  There, we may receive the same appl_ptr
value, and in such a case, calling ack is obviously superfluous.

This patch adds the check of the given appl_ptr value, and returns
immediately if it's no real update.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-06-14 07:44:27 +02:00
..
aoa ALSA: declare snd_kcontrol_new structures as const 2017-05-30 10:29:25 +02:00
arm ALSA: arm: Fix empty menuconfig SND_ARM 2016-08-01 16:07:53 +02:00
atmel ALSA: atmel: Remove AVR32 bits from the driver 2017-05-15 17:07:00 +02:00
core ALSA: pcm: Skip ack callback without actual appl_ptr update 2017-06-14 07:44:27 +02:00
drivers ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
firewire ALSA: firewire: arrange common PCM info/constraints for AMDTP engine applications 2017-06-08 09:15:44 +02:00
hda ALSA: hda: Fix cpu lockup when stopping the cmd dmas 2017-05-10 08:47:17 +02:00
i2c ALSA: ak411x: Use array instead of offsetof() 2017-05-17 07:13:03 +02:00
isa ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
mips ALSA: declare snd_kcontrol_new structures as const 2017-05-30 10:29:25 +02:00
oss Annotate hardware config module parameters in sound/oss/ 2017-04-20 12:02:32 +01:00
parisc ALSA: parisc: Constify hw_constraints 2017-06-09 10:42:48 +02:00
pci ALSA: seq: Allow the modular sequencer registration 2017-06-12 08:43:33 +02:00
pcmcia ALSA: declare snd_kcontrol_new structures as const 2017-05-30 10:29:25 +02:00
ppc ALSA: declare snd_kcontrol_new structures as const 2017-05-30 10:29:25 +02:00
sh ALSA: sh: Convert to the new PCM ops 2017-06-02 19:38:03 +02:00
soc Merge branch 'for-linus' into for-next 2017-06-07 10:25:30 +02:00
sparc ALSA: sparc: Constify hw_constraints 2017-06-09 10:42:56 +02:00
spi ALSA: at73c213: manage SSC clock 2016-01-20 09:59:27 +01:00
synth ALSA: synth: Select snd-emux-synth explicitly 2017-06-09 22:10:06 +02:00
usb Merge branch 'for-linus' into for-next 2017-06-07 10:25:30 +02:00
x86 drm/i915: Fix runtime PM for LPE audio 2017-05-15 14:44:11 +03:00
Kconfig ALSA: synth: Select snd-emux-synth explicitly 2017-06-09 22:10:06 +02:00
Makefile ALSA: add Intel HDMI LPE audio driver for BYT/CHT-T 2017-01-25 14:23:46 +01:00
ac97_bus.c ASoC: Updates for v4.3 2015-08-31 16:25:22 +02:00
last.c
sound_core.c sound: fix check for error condition of register_chrdev() 2015-11-07 11:14:30 +01:00