diff options
| -rw-r--r-- | sound/firewire/amdtp.c | 8 | ||||
| -rw-r--r-- | sound/firewire/amdtp.h | 1 |
2 files changed, 8 insertions, 1 deletions
diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c index c2685fbd736..ea995af6d04 100644 --- a/sound/firewire/amdtp.c +++ b/sound/firewire/amdtp.c @@ -178,6 +178,7 @@ void amdtp_out_stream_pcm_prepare(struct amdtp_out_stream *s) tasklet_kill(&s->period_tasklet); s->pcm_buffer_pointer = 0; s->pcm_period_pointer = 0; + s->pointer_flush = true; } EXPORT_SYMBOL(amdtp_out_stream_pcm_prepare); @@ -393,6 +394,7 @@ static void queue_out_packet(struct amdtp_out_stream *s, unsigned int cycle) s->pcm_period_pointer += data_blocks; if (s->pcm_period_pointer >= pcm->runtime->period_size) { s->pcm_period_pointer -= pcm->runtime->period_size; + s->pointer_flush = false; tasklet_hi_schedule(&s->period_tasklet); } } @@ -539,7 +541,11 @@ EXPORT_SYMBOL(amdtp_out_stream_start); */ unsigned long amdtp_out_stream_pcm_pointer(struct amdtp_out_stream *s) { - fw_iso_context_flush_completions(s->context); + /* this optimization is allowed to be racy */ + if (s->pointer_flush) + fw_iso_context_flush_completions(s->context); + else + s->pointer_flush = true; return ACCESS_ONCE(s->pcm_buffer_pointer); } diff --git a/sound/firewire/amdtp.h b/sound/firewire/amdtp.h index 3f13ff63c5d..b680c5ef01d 100644 --- a/sound/firewire/amdtp.h +++ b/sound/firewire/amdtp.h @@ -68,6 +68,7 @@ struct amdtp_out_stream { unsigned int pcm_buffer_pointer; unsigned int pcm_period_pointer; + bool pointer_flush; }; int amdtp_out_stream_init(struct amdtp_out_stream *s, struct fw_unit *unit, |