Keep track of boundary crossing when hw_ptr exceeds boundary limit and wraps-around. This will help keep track of total number of frames played/received at the kernel level
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- include/sound/pcm.h | 1 + sound/core/pcm_lib.c | 25 ++++++++++++++++++++----- 2 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/include/sound/pcm.h b/include/sound/pcm.h index 6268a41..28fd9f9 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -281,6 +281,7 @@ struct snd_pcm_runtime { unsigned long hw_ptr_jiffies; /* Time when hw_ptr is updated */ unsigned long hw_ptr_buffer_jiffies; /* buffer time in jiffies */ snd_pcm_sframes_t delay; /* extra delay; typically FIFO size */ + u64 hw_ptr_wrap; /* offset for hw_ptr due to boundary wrap-around */
/* -- HW params -- */ snd_pcm_access_t access; /* access mode */ diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index f42c10a..3dc029e 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -316,6 +316,7 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, unsigned long jdelta; unsigned long curr_jiffies; struct timespec curr_tstamp; + int crossed_boundary = 0;
old_hw_ptr = runtime->status->hw_ptr;
@@ -360,8 +361,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, hdelta = curr_jiffies - runtime->hw_ptr_jiffies; if (hdelta > runtime->hw_ptr_buffer_jiffies/2) { hw_base += runtime->buffer_size; - if (hw_base >= runtime->boundary) + if (hw_base >= runtime->boundary) { hw_base = 0; + crossed_boundary++; + } new_hw_ptr = hw_base + pos; goto __delta; } @@ -371,8 +374,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, /* pointer crosses the end of the ring buffer */ if (new_hw_ptr < old_hw_ptr) { hw_base += runtime->buffer_size; - if (hw_base >= runtime->boundary) + if (hw_base >= runtime->boundary) { hw_base = 0; + crossed_boundary++; + } new_hw_ptr = hw_base + pos; } __delta: @@ -410,8 +415,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, while (hdelta > xrun_threshold) { delta += runtime->buffer_size; hw_base += runtime->buffer_size; - if (hw_base >= runtime->boundary) + if (hw_base >= runtime->boundary) { hw_base = 0; + crossed_boundary++; + } new_hw_ptr = hw_base + pos; hdelta -= runtime->hw_ptr_buffer_jiffies; } @@ -456,8 +463,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, /* the delta value is small or zero in most cases */ while (delta > 0) { new_hw_ptr += runtime->period_size; - if (new_hw_ptr >= runtime->boundary) + if (new_hw_ptr >= runtime->boundary) { new_hw_ptr -= runtime->boundary; + crossed_boundary--; + } delta--; } /* align hw_base to buffer_size */ @@ -507,6 +516,10 @@ static int snd_pcm_update_hw_ptr0(struct snd_pcm_substream *substream, runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; runtime->hw_ptr_jiffies = curr_jiffies; + if (crossed_boundary) { + snd_BUG_ON(crossed_boundary != 1); + runtime->hw_ptr_wrap += runtime->boundary; + } if (runtime->tstamp_mode == SNDRV_PCM_TSTAMP_ENABLE) runtime->status->tstamp = curr_tstamp;
@@ -1661,8 +1674,10 @@ static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream, if (snd_pcm_running(substream) && snd_pcm_update_hw_ptr(substream) >= 0) runtime->status->hw_ptr %= runtime->buffer_size; - else + else { runtime->status->hw_ptr = 0; + runtime->hw_ptr_wrap = 0; + } snd_pcm_stream_unlock_irqrestore(substream, flags); return 0; }