diff options
Diffstat (limited to 'sound/pci/es1968.c')
| -rw-r--r-- | sound/pci/es1968.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/sound/pci/es1968.c b/sound/pci/es1968.c index 67f03264f87..f8f3bb662d1 100644 --- a/sound/pci/es1968.c +++ b/sound/pci/es1968.c @@ -1827,6 +1827,23 @@ snd_es1968_pcm(struct es1968 *chip, int device) return 0; } +/* + * suppress jitter on some maestros when playing stereo + */ +static void snd_es1968_suppress_jitter(struct es1968 *chip, struct esschan *es) +{ + unsigned int cp1; + unsigned int cp2; + unsigned int diff; + + cp1 = __apu_get_register(chip, 0, 5); + cp2 = __apu_get_register(chip, 1, 5); + diff = (cp1 > cp2 ? cp1 - cp2 : cp2 - cp1); + + if (diff > 1) { + __maestro_write(chip, IDR0_DATA_PORT, cp1); + } +} /* * update pointer @@ -1948,8 +1965,11 @@ static irqreturn_t snd_es1968_interrupt(int irq, void *dev_id) struct esschan *es; spin_lock(&chip->substream_lock); list_for_each_entry(es, &chip->substream_list, list) { - if (es->running) + if (es->running) { snd_es1968_update_pcm(chip, es); + if (es->fmt & ESS_FMT_STEREO) + snd_es1968_suppress_jitter(chip, es); + } } spin_unlock(&chip->substream_lock); if (chip->in_measurement) { |