[ALSA] ymfpci: change timer resolution to 48 kHz

Modules: YMFPCI driver

We better pretend that the ymfpci timer runs at 48 kHz because the
interrupt frequency cannot be higher, and clients that would try to
use 96 kHz would run at half their desired speed.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
This commit is contained in:
Clemens Ladisch 2005-10-19 14:39:48 +02:00 committed by Jaroslav Kysela
parent 87ef7779be
commit d44c39acaf

View file

@ -1851,9 +1851,7 @@ static int snd_ymfpci_timer_start(snd_timer_t *timer)
unsigned int count; unsigned int count;
chip = snd_timer_chip(timer); chip = snd_timer_chip(timer);
count = timer->sticks - 1; count = (timer->sticks << 1) - 1;
if (count == 0) /* minimum time is 20.8 us */
count = 1;
spin_lock_irqsave(&chip->reg_lock, flags); spin_lock_irqsave(&chip->reg_lock, flags);
snd_ymfpci_writew(chip, YDSXGR_TIMERCOUNT, count); snd_ymfpci_writew(chip, YDSXGR_TIMERCOUNT, count);
snd_ymfpci_writeb(chip, YDSXGR_TIMERCTRL, 0x03); snd_ymfpci_writeb(chip, YDSXGR_TIMERCTRL, 0x03);
@ -1877,14 +1875,14 @@ static int snd_ymfpci_timer_precise_resolution(snd_timer_t *timer,
unsigned long *num, unsigned long *den) unsigned long *num, unsigned long *den)
{ {
*num = 1; *num = 1;
*den = 96000; *den = 48000;
return 0; return 0;
} }
static struct _snd_timer_hardware snd_ymfpci_timer_hw = { static struct _snd_timer_hardware snd_ymfpci_timer_hw = {
.flags = SNDRV_TIMER_HW_AUTO, .flags = SNDRV_TIMER_HW_AUTO,
.resolution = 10417, /* 1/2fs = 10.41666...us */ .resolution = 20833, /* 1/fs = 20.8333...us */
.ticks = 65536, .ticks = 0x8000,
.start = snd_ymfpci_timer_start, .start = snd_ymfpci_timer_start,
.stop = snd_ymfpci_timer_stop, .stop = snd_ymfpci_timer_stop,
.precise_resolution = snd_ymfpci_timer_precise_resolution, .precise_resolution = snd_ymfpci_timer_precise_resolution,