Re: [alsa-devel] [PATCH 3/3] ALSA: pcm: Unify delay calculation in snd_pcm_status() and snd_pcm_delay()

Hi,

On Apr 17 2018 14:20, Takashi Iwai wrote:

Subject: [PATCH v2 3/3] ALSA: pcm: Unify delay calculation in snd_pcm_status() and snd_pcm_delay()

Yet another slight code cleanup: there are two places where calculating the PCM delay, and they can be unified in a single helper. It reduces the multiple open codes.

Signed-off-by: Takashi Iwai tiwai@suse.de

sound/core/pcm_native.c | 37 ++++++++++++++++--------------------- 1 file changed, 16 insertions(+), 21 deletions(-)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index eddb0cd6d1eb..7585444352df 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -857,6 +857,18 @@ static int snd_pcm_sw_params_user(struct snd_pcm_substream *substream, return err; }

+static inline snd_pcm_uframes_t +snd_pcm_calc_delay(struct snd_pcm_substream *substream) +{

• snd_pcm_uframes_t delay;
• if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)

• delay = snd_pcm_playback_hw_avail(substream->runtime);
  

• else

• delay = snd_pcm_capture_avail(substream->runtime);
  

• return delay + substream->runtime->delay;

+}

• int snd_pcm_status(struct snd_pcm_substream *substream, struct snd_pcm_status *status) {

@@ -909,19 +921,8 @@ int snd_pcm_status(struct snd_pcm_substream *substream, status->appl_ptr = runtime->control->appl_ptr; status->hw_ptr = runtime->status->hw_ptr; status->avail = snd_pcm_avail(substream);

• if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {

• if (runtime->status->state == SNDRV_PCM_STATE_RUNNING ||
  

•     runtime->status->state == SNDRV_PCM_STATE_DRAINING) {
  

• 	status->delay = runtime->buffer_size - status->avail;
  

• 	status->delay += runtime->delay;
  

• } else
  

• 	status->delay = 0;
  

• } else {

• if (runtime->status->state == SNDRV_PCM_STATE_RUNNING)
  

• 	status->delay = status->avail + runtime->delay;
  

• else
  

• 	status->delay = 0;
  

• }

• status->delay = snd_pcm_running(substream) ?

• snd_pcm_calc_delay(substream) : 0;
  

  status->avail_max = runtime->avail_max; status->overrange = runtime->overrange; runtime->avail_max = 0;

@@ -2655,19 +2656,13 @@ static int snd_pcm_hwsync(struct snd_pcm_substream *substream) static snd_pcm_sframes_t snd_pcm_delay(struct snd_pcm_substream *substream) {

• struct snd_pcm_runtime *runtime = substream->runtime; int err; snd_pcm_sframes_t n = 0;

  snd_pcm_stream_lock_irq(substream); err = do_pcm_hwsync(substream);

• if (!err) {

• if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  

• 	n = snd_pcm_playback_hw_avail(runtime);
  

• else
  

• 	n = snd_pcm_capture_avail(runtime);
  

• n += runtime->delay;
  

• }

• if (!err)

• n = snd_pcm_calc_delay(substream);
  

  snd_pcm_stream_unlock_irq(substream); return err < 0 ? err : n; }

Oh, 'snd_pcm_running()' is exactly suitable for this case ;)

Reviewed-by: Takashi Sakamoto o-takashi@sakamocchi.jp

Thanks

Takashi Sakamoto