diff options
Diffstat (limited to 'sound/pci/emu10k1/timer.c')
-rw-r--r-- | sound/pci/emu10k1/timer.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/sound/pci/emu10k1/timer.c b/sound/pci/emu10k1/timer.c new file mode 100644 index 000000000..2435d3ba6 --- /dev/null +++ b/sound/pci/emu10k1/timer.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) by Lee Revell <rlrevell@joe-job.com> + * Clemens Ladisch <clemens@ladisch.de> + * Routines for control of EMU10K1 chips + * + * BUGS: + * -- + * + * TODO: + * -- + */ + +#include <linux/time.h> +#include <sound/core.h> +#include <sound/emu10k1.h> + +static int snd_emu10k1_timer_start(struct snd_timer *timer) +{ + struct snd_emu10k1 *emu; + unsigned long flags; + unsigned int delay; + + emu = snd_timer_chip(timer); + delay = timer->sticks - 1; + if (delay < 5 ) /* minimum time is 5 ticks */ + delay = 5; + spin_lock_irqsave(&emu->reg_lock, flags); + snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB); + outw(delay & TIMER_RATE_MASK, emu->port + TIMER); + spin_unlock_irqrestore(&emu->reg_lock, flags); + return 0; +} + +static int snd_emu10k1_timer_stop(struct snd_timer *timer) +{ + struct snd_emu10k1 *emu; + unsigned long flags; + + emu = snd_timer_chip(timer); + spin_lock_irqsave(&emu->reg_lock, flags); + snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB); + spin_unlock_irqrestore(&emu->reg_lock, flags); + return 0; +} + +static int snd_emu10k1_timer_precise_resolution(struct snd_timer *timer, + unsigned long *num, unsigned long *den) +{ + *num = 1; + *den = 48000; + return 0; +} + +static const struct snd_timer_hardware snd_emu10k1_timer_hw = { + .flags = SNDRV_TIMER_HW_AUTO, + .resolution = 20833, /* 1 sample @ 48KHZ = 20.833...us */ + .ticks = 1024, + .start = snd_emu10k1_timer_start, + .stop = snd_emu10k1_timer_stop, + .precise_resolution = snd_emu10k1_timer_precise_resolution, +}; + +int snd_emu10k1_timer(struct snd_emu10k1 *emu, int device) +{ + struct snd_timer *timer = NULL; + struct snd_timer_id tid; + int err; + + tid.dev_class = SNDRV_TIMER_CLASS_CARD; + tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; + tid.card = emu->card->number; + tid.device = device; + tid.subdevice = 0; + err = snd_timer_new(emu->card, "EMU10K1", &tid, &timer); + if (err >= 0) { + strcpy(timer->name, "EMU10K1 timer"); + timer->private_data = emu; + timer->hw = snd_emu10k1_timer_hw; + } + emu->timer = timer; + return err; +} |