linux/sound/core
Koro Chen 13a988396c ALSA: pcm: Modify double acknowledged interrupts check condition
Currently in snd_pcm_update_hw_ptr0 during interrupt,
we consider there were double acknowledged interrupts when:
1. HW reported pointer is smaller than expected, and
2. Time from last update time (hdelta) is over half a buffer time.

However, when HW reported pointer is only a few bytes smaller than
expected, and when hdelta is just a little larger than half a buffer time
(e.g. ping-pong buffer), it wrongly treats this IRQ as double acknowledged.

The condition #2 uses jiffies, but jiffies is not high resolution
since it is integer. We should consider jiffies inaccuracy.

Signed-off-by: Koro Chen <koro.chen@mediatek.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-05-19 09:32:29 +02:00
..
oss
seq
Kconfig
Makefile
compress_offload.c
control.c
control_compat.c
ctljack.c
device.c
hrtimer.c
hwdep.c
hwdep_compat.c
info.c
info_oss.c
init.c
isadma.c
jack.c
memalloc.c
memory.c
misc.c
pcm.c
pcm_compat.c
pcm_dmaengine.c
pcm_lib.c
pcm_memory.c
pcm_misc.c
pcm_native.c
pcm_timer.c
pcm_trace.h
rawmidi.c
rawmidi_compat.c
rtctimer.c
sgbuf.c
sound.c
sound_oss.c
timer.c
timer_compat.c
vmaster.c