diff options
Diffstat (limited to 'sound/core/pcm_lib.c')
| -rw-r--r-- | sound/core/pcm_lib.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 11446a1506d..a82e3756a72 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -373,6 +373,27 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, (unsigned long)new_hw_ptr, (unsigned long)runtime->hw_ptr_base); } + + if (runtime->no_period_wakeup) { + /* + * Without regular period interrupts, we have to check + * the elapsed time to detect xruns. + */ + jdelta = jiffies - runtime->hw_ptr_jiffies; + if (jdelta < runtime->hw_ptr_buffer_jiffies / 2) + goto no_delta_check; + hdelta = jdelta - delta * HZ / runtime->rate; + while (hdelta > runtime->hw_ptr_buffer_jiffies / 2 + 1) { + delta += runtime->buffer_size; + hw_base += runtime->buffer_size; + if (hw_base >= runtime->boundary) + hw_base = 0; + new_hw_ptr = hw_base + pos; + hdelta -= runtime->hw_ptr_buffer_jiffies; + } + goto no_delta_check; + } + /* something must be really wrong */ if (delta >= runtime->buffer_size + runtime->period_size) { hw_ptr_error(substream, @@ -442,6 +463,7 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, (long)old_hw_ptr); } + no_delta_check: if (runtime->status->hw_ptr == new_hw_ptr) return 0; |