5 * Copyright (C) by Hannu Savolainen 1993-1997
7 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
8 * Version 2 (June 1991). See the "COPYING" file distributed with this software
12 * Thomas Sailer : ioctl code reworked (vmalloc/vfree removed)
14 #include <linux/string.h>
15 #include <linux/spinlock.h>
17 #include "sound_config.h"
19 static volatile int initialized, opened, tmr_running;
20 static volatile time_t tmr_offs, tmr_ctr;
21 static volatile unsigned long ticks_offs;
22 static volatile int curr_tempo, curr_timebase;
23 static volatile unsigned long curr_ticks;
24 static volatile unsigned long next_event_time;
25 static unsigned long prev_event_time;
26 static volatile unsigned long usecs_per_tmr; /* Length of the current interval */
28 static struct sound_lowlev_timer *tmr;
29 static spinlock_t lock;
31 static unsigned long tmr2ticks(int tmr_value)
34 * Convert timer ticks to MIDI ticks
40 tmp = tmr_value * usecs_per_tmr; /* Convert to usecs */
41 scale = (60 * 1000000) / (curr_tempo * curr_timebase); /* usecs per MIDI tick */
42 return (tmp + (scale / 2)) / scale;
45 void reprogram_timer(void)
47 unsigned long usecs_per_tick;
50 * The user is changing the timer rate before setting a timer
51 * slap, bad bad not allowed.
57 usecs_per_tick = (60 * 1000000) / (curr_tempo * curr_timebase);
60 * Don't kill the system by setting too high timer rate
62 if (usecs_per_tick < 2000)
63 usecs_per_tick = 2000;
65 usecs_per_tmr = tmr->tmr_start(tmr->dev, usecs_per_tick);
68 void sound_timer_syncinterval(unsigned int new_usecs)
71 * This routine is called by the hardware level if
72 * the clock frequency has changed for some reason.
75 ticks_offs += tmr2ticks(tmr_ctr);
77 usecs_per_tmr = new_usecs;
80 static void tmr_reset(void)
84 spin_lock_irqsave(&lock,flags);
88 next_event_time = (unsigned long) -1;
91 spin_unlock_irqrestore(&lock,flags);
94 static int timer_open(int dev, int mode)
106 static void timer_close(int dev)
108 opened = tmr_running = 0;
109 tmr->tmr_disable(tmr->dev);
112 static int timer_event(int dev, unsigned char *event)
114 unsigned char cmd = event[1];
115 unsigned long parm = *(int *) &event[4];
120 parm += prev_event_time;
126 if (parm <= curr_ticks) /* It's the time */
127 return TIMER_NOT_ARMED;
129 next_event_time = prev_event_time = time;
157 ticks_offs += tmr2ticks(tmr_ctr);
165 seq_copy_to_input(event, 8);
170 return TIMER_NOT_ARMED;
173 static unsigned long timer_get_time(int dev)
180 static int timer_ioctl(int dev, unsigned int cmd, caddr_t arg)
186 case SNDCTL_TMR_SOURCE:
190 case SNDCTL_TMR_START:
195 case SNDCTL_TMR_STOP:
199 case SNDCTL_TMR_CONTINUE:
203 case SNDCTL_TMR_TIMEBASE:
204 if (get_user(val, (int *)arg))
217 case SNDCTL_TMR_TEMPO:
218 if (get_user(val, (int *)arg))
227 ticks_offs += tmr2ticks(tmr_ctr);
235 case SNDCTL_SEQ_CTRLRATE:
236 if (get_user(val, (int *)arg))
238 if (val != 0) /* Can't change */
240 val = ((curr_tempo * curr_timebase) + 30) / 60;
243 case SNDCTL_SEQ_GETTIME:
247 case SNDCTL_TMR_METRONOME:
251 return put_user(val, (int *)arg);
254 static void timer_arm(int dev, long time)
257 time = curr_ticks + 1;
258 else if (time <= curr_ticks) /* It's the time */
261 next_event_time = prev_event_time = time;
265 static struct sound_timer_operations sound_timer =
267 .owner = THIS_MODULE,
268 .info = {"Sound Timer", 0},
269 .priority = 1, /* Priority */
270 .devlink = 0, /* Local device link */
272 .close = timer_close,
273 .event = timer_event,
274 .get_time = timer_get_time,
275 .ioctl = timer_ioctl,
276 .arm_timer = timer_arm
279 void sound_timer_interrupt(void)
286 tmr->tmr_restart(tmr->dev);
291 spin_lock_irqsave(&lock,flags);
293 curr_ticks = ticks_offs + tmr2ticks(tmr_ctr);
295 if (curr_ticks >= next_event_time)
297 next_event_time = (unsigned long) -1;
300 spin_unlock_irqrestore(&lock,flags);
303 void sound_timer_init(struct sound_lowlev_timer *t, char *name)
309 if (t->priority <= tmr->priority)
310 return; /* There is already a similar or better timer */
317 n = sound_alloc_timerdev();
319 n = 0; /* Overwrite the system timer */
320 strcpy(sound_timer.info.name, name);
321 sound_timer_devs[n] = &sound_timer;