diff options
| author | Takashi Iwai <tiwai@suse.de> | 2009-04-28 12:07:08 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2009-04-28 15:10:16 +0200 |
| commit | 3e5b50165fd0be080044586f43fcdd460ed27610 (patch) | |
| tree | 54e6ed455de1f011b7da25234553c4b61f4a3f08 /sound | |
| parent | 2008f137e92220b98120c4803499cdddb2b0fb06 (diff) | |
| download | linux-next-3e5b50165fd0be080044586f43fcdd460ed27610.tar.gz | |
ALSA: pcm core - Avoid jiffies check for devices with BATCH flag
The hardware devices with SNDRV_PCM_INFO_BATCH flag can't give the
precise current position. And such hardwares have often big FIFO
in addition to the ring buffer, and it screws up the jiffies check
in pcm_lib.c.
This patch adds a simple check of info flag so that the driver skips
the jiffies check in snd_pcm_period_elapsed() when BATCH flag is set.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/core/pcm_lib.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 63d088f2265f..a2a792c18c40 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -249,6 +249,12 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; } } + /* Skip the jiffies check for hardwares with BATCH flag. + * Such hardware usually just increases the position at each IRQ, + * thus it can't give any strange position. + */ + if (runtime->hw.info & SNDRV_PCM_INFO_BATCH) + goto no_jiffies_check; hdelta = new_hw_ptr - old_hw_ptr; jdelta = jiffies - runtime->hw_ptr_jiffies; if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) { @@ -272,6 +278,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) hw_base -= hw_base % runtime->buffer_size; delta = 0; } + no_jiffies_check: if (delta > runtime->period_size + runtime->period_size / 2) { hw_ptr_error(substream, "Lost interrupts? " |