ALSA: PCM midlevel: lower jiffies check margin using runtime->delay value

When hardware has large FIFO, it is necessary to lower jiffies margin
by count of queued samples.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 0f299a5..dd9126b 100644 (file)
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -263,6 +263,9 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream)
        if (runtime->hw.info & SNDRV_PCM_INFO_BATCH)
                goto no_jiffies_check;
        hdelta = new_hw_ptr - old_hw_ptr;
+       if (hdelta < runtime->delay)
+               goto no_jiffies_check;
+       hdelta -= runtime->delay;
        jdelta = jiffies - runtime->hw_ptr_jiffies;
        if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) {
                delta = jdelta /
@@ -349,8 +352,12 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
                new_hw_ptr = hw_base + pos;
        }
        /* Do jiffies check only in xrun_debug mode */
-       if (xrun_debug(substream, 4) &&
-           ((delta * HZ) / runtime->rate) > jdelta + HZ/100) {
+       if (!xrun_debug(substream, 4))
+               goto no_jiffies_check;
+       if (delta < runtime->delay)
+               goto no_jiffies_check;
+       delta -= runtime->delay;
+       if (((delta * HZ) / runtime->rate) > jdelta + HZ/100) {
                hw_ptr_error(substream,
                             "hw_ptr skipping! "
                             "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu)\n",
@@ -359,6 +366,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream)
                             ((delta * HZ) / runtime->rate));
                return 0;
        }
+ no_jiffies_check:
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
            runtime->silence_size > 0)
                snd_pcm_playback_silence(substream, new_hw_ptr);