freebsd-dev/sys/i386/isa/sound/sound_timer.c

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/*
* sound/sound_timer.c
*
* Timer for the level 2 interface of the /dev/sequencer. Uses the
* 80 and 320 usec timers of OPL-3 (PAS16 only) and GUS.
*
* Copyright by Hannu Savolainen 1993
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer. 2.
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#define SEQUENCER_C
#include "sound_config.h"
#ifdef CONFIGURE_SOUNDCARD
#if !defined(EXCLUDE_SEQUENCER) && (!defined(EXCLUDE_GUS) || (!defined(EXCLUDE_PAS) && !defined(EXCLUDE_YM3812)))
static volatile int initialized = 0, opened = 0, tmr_running = 0;
static volatile time_t tmr_offs, tmr_ctr;
static volatile unsigned long ticks_offs;
static volatile int curr_tempo, curr_timebase;
static volatile unsigned long curr_ticks;
static volatile unsigned long next_event_time;
static unsigned long prev_event_time;
static volatile int select_addr, data_addr;
static volatile int curr_timer = 0;
static volatile unsigned long usecs_per_tmr; /* Length of the current interval */
static void
timer_command (unsigned int addr, unsigned int val)
{
int i;
OUTB ((unsigned char) (addr & 0xff), select_addr);
for (i = 0; i < 2; i++)
INB (select_addr);
OUTB ((unsigned char) (val & 0xff), data_addr);
for (i = 0; i < 2; i++)
INB (select_addr);
}
static void
arm_timer (int timer, unsigned int interval)
{
curr_timer = timer;
if (timer == 1)
{
gus_write8 (0x46, 256 - interval); /* Set counter for timer 1 */
gus_write8 (0x45, 0x04); /* Enable timer 1 IRQ */
timer_command (0x04, 0x01); /* Start timer 1 */
}
else
{
gus_write8 (0x47, 256 - interval); /* Set counter for timer 2 */
gus_write8 (0x45, 0x08); /* Enable timer 2 IRQ */
timer_command (0x04, 0x02); /* Start timer 2 */
}
}
static unsigned long
tmr2ticks (int tmr_value)
{
/*
* Convert timer ticks to MIDI ticks
*/
unsigned long tmp;
unsigned long scale;
tmp = tmr_value * usecs_per_tmr; /* Convert to usecs */
scale = (60 * 1000000) / (curr_tempo * curr_timebase); /* usecs per MIDI tick */
return (tmp + (scale / 2)) / scale;
}
static void
reprogram_timer (void)
{
unsigned long usecs_per_tick;
int timer_no, resolution;
int divisor;
usecs_per_tick = (60 * 1000000) / (curr_tempo * curr_timebase);
/*
* Don't kill the system by setting too high timer rate
*/
if (usecs_per_tick < 2000)
usecs_per_tick = 2000;
if (usecs_per_tick > (256 * 80))
{
timer_no = 2;
resolution = 320; /* usec */
}
else
{
timer_no = 1;
resolution = 80; /* usec */
}
divisor = (usecs_per_tick + (resolution / 2)) / resolution;
usecs_per_tmr = divisor * resolution;
arm_timer (timer_no, divisor);
}
static void
tmr_reset (void)
{
unsigned long flags;
DISABLE_INTR (flags);
tmr_offs = 0;
ticks_offs = 0;
tmr_ctr = 0;
next_event_time = 0xffffffff;
prev_event_time = 0;
curr_ticks = 0;
RESTORE_INTR (flags);
}
static int
timer_open (int dev, int mode)
{
if (opened)
return RET_ERROR (EBUSY);
tmr_reset ();
curr_tempo = 60;
curr_timebase = HZ;
opened = 1;
reprogram_timer ();
return 0;
}
static void
timer_close (int dev)
{
opened = tmr_running = 0;
gus_write8 (0x45, 0); /* Disable both timers */
}
static int
timer_event (int dev, unsigned char *event)
{
unsigned char cmd = event[1];
unsigned long parm = *(int *) &event[4];
switch (cmd)
{
case TMR_WAIT_REL:
parm += prev_event_time;
case TMR_WAIT_ABS:
if (parm > 0)
{
long time;
if (parm <= curr_ticks) /* It's the time */
return TIMER_NOT_ARMED;
time = parm;
next_event_time = prev_event_time = time;
return TIMER_ARMED;
}
break;
case TMR_START:
tmr_reset ();
tmr_running = 1;
reprogram_timer ();
break;
case TMR_STOP:
tmr_running = 0;
break;
case TMR_CONTINUE:
tmr_running = 1;
reprogram_timer ();
break;
case TMR_TEMPO:
if (parm)
{
if (parm < 8)
parm = 8;
if (parm > 250)
parm = 250;
tmr_offs = tmr_ctr;
ticks_offs += tmr2ticks (tmr_ctr);
tmr_ctr = 0;
curr_tempo = parm;
reprogram_timer ();
}
break;
case TMR_ECHO:
seq_copy_to_input (event, 8);
break;
default:;
}
return TIMER_NOT_ARMED;
}
static unsigned long
timer_get_time (int dev)
{
if (!opened)
return 0;
return curr_ticks;
}
static int
timer_ioctl (int dev,
unsigned int cmd, unsigned int arg)
{
switch (cmd)
{
case SNDCTL_TMR_SOURCE:
return IOCTL_OUT (arg, TMR_INTERNAL);
break;
case SNDCTL_TMR_START:
tmr_reset ();
tmr_running = 1;
return 0;
break;
case SNDCTL_TMR_STOP:
tmr_running = 0;
return 0;
break;
case SNDCTL_TMR_CONTINUE:
tmr_running = 1;
return 0;
break;
case SNDCTL_TMR_TIMEBASE:
{
int val = IOCTL_IN (arg);
if (val)
{
if (val < 1)
val = 1;
if (val > 1000)
val = 1000;
curr_timebase = val;
}
return IOCTL_OUT (arg, curr_timebase);
}
break;
case SNDCTL_TMR_TEMPO:
{
int val = IOCTL_IN (arg);
if (val)
{
if (val < 8)
val = 8;
if (val > 250)
val = 250;
tmr_offs = tmr_ctr;
ticks_offs += tmr2ticks (tmr_ctr);
tmr_ctr = 0;
curr_tempo = val;
reprogram_timer ();
}
return IOCTL_OUT (arg, curr_tempo);
}
break;
case SNDCTL_SEQ_CTRLRATE:
if (IOCTL_IN (arg) != 0) /* Can't change */
return RET_ERROR (EINVAL);
return IOCTL_OUT (arg, ((curr_tempo * curr_timebase) + 30) / 60);
break;
case SNDCTL_TMR_METRONOME:
/* NOP */
break;
default:
}
return RET_ERROR (EINVAL);
}
static void
timer_arm (int dev, long time)
{
if (time < 0)
time = curr_ticks + 1;
else if (time <= curr_ticks) /* It's the time */
return;
next_event_time = prev_event_time = time;
return;
}
static struct sound_timer_operations sound_timer =
{
{"OPL-3/GUS Timer", 0},
1, /* Priority */
0, /* Local device link */
timer_open,
timer_close,
timer_event,
timer_get_time,
timer_ioctl,
timer_arm
};
void
sound_timer_interrupt (void)
{
gus_write8 (0x45, 0); /* Ack IRQ */
timer_command (4, 0x80); /* Reset IRQ flags */
if (!opened)
return;
if (curr_timer == 1)
gus_write8 (0x45, 0x04); /* Start timer 1 again */
else
gus_write8 (0x45, 0x08); /* Start timer 2 again */
if (!tmr_running)
return;
tmr_ctr++;
curr_ticks = ticks_offs + tmr2ticks (tmr_ctr);
if (curr_ticks >= next_event_time)
{
next_event_time = 0xffffffff;
sequencer_timer ();
}
}
void
sound_timer_init (int io_base)
{
int n;
if (initialized)
return; /* There is already a similar timer */
select_addr = io_base;
data_addr = io_base + 1;
initialized = 1;
#if 1
if (num_sound_timers >= MAX_TIMER_DEV)
n = 0; /* Overwrite the system timer */
else
n = num_sound_timers++;
#else
n = 0;
#endif
sound_timer_devs[n] = &sound_timer;
}
#endif
#endif