--- /dev/null
+/*
+ * sound/oss/sound_timer.c
+ */
+/*
+ * Copyright (C) by Hannu Savolainen 1993-1997
+ *
+ * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
+ * Version 2 (June 1991). See the "COPYING" file distributed with this software
+ * for more info.
+ */
+/*
+ * Thomas Sailer : ioctl code reworked (vmalloc/vfree removed)
+ */
+#include <linux/string.h>
+#include <linux/spinlock.h>
+
+#include "sound_config.h"
+
+static volatile int initialized, opened, tmr_running;
+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 unsigned long usecs_per_tmr; /* Length of the current interval */
+
+static struct sound_lowlev_timer *tmr;
+static DEFINE_SPINLOCK(lock);
+
+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;
+}
+
+void reprogram_timer(void)
+{
+ unsigned long usecs_per_tick;
+
+ /*
+ * The user is changing the timer rate before setting a timer
+ * slap, bad bad not allowed.
+ */
+
+ if(!tmr)
+ return;
+
+ 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;
+
+ usecs_per_tmr = tmr->tmr_start(tmr->dev, usecs_per_tick);
+}
+
+void sound_timer_syncinterval(unsigned int new_usecs)
+{
+ /*
+ * This routine is called by the hardware level if
+ * the clock frequency has changed for some reason.
+ */
+ tmr_offs = tmr_ctr;
+ ticks_offs += tmr2ticks(tmr_ctr);
+ tmr_ctr = 0;
+ usecs_per_tmr = new_usecs;
+}
+EXPORT_SYMBOL(sound_timer_syncinterval);
+
+static void tmr_reset(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&lock,flags);
+ tmr_offs = 0;
+ ticks_offs = 0;
+ tmr_ctr = 0;
+ next_event_time = (unsigned long) -1;
+ prev_event_time = 0;
+ curr_ticks = 0;
+ spin_unlock_irqrestore(&lock,flags);
+}
+
+static int timer_open(int dev, int mode)
+{
+ if (opened)
+ return -EBUSY;
+ tmr_reset();
+ curr_tempo = 60;
+ curr_timebase = 100;
+ opened = 1;
+ reprogram_timer();
+ return 0;
+}
+
+static void timer_close(int dev)
+{
+ opened = tmr_running = 0;
+ tmr->tmr_disable(tmr->dev);
+}
+
+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, void __user *arg)
+{
+ int __user *p = arg;
+ int val;
+
+ switch (cmd)
+ {
+ case SNDCTL_TMR_SOURCE:
+ val = TMR_INTERNAL;
+ break;
+
+ case SNDCTL_TMR_START:
+ tmr_reset();
+ tmr_running = 1;
+ return 0;
+
+ case SNDCTL_TMR_STOP:
+ tmr_running = 0;
+ return 0;
+
+ case SNDCTL_TMR_CONTINUE:
+ tmr_running = 1;
+ return 0;
+
+ case SNDCTL_TMR_TIMEBASE:
+ if (get_user(val, p))
+ return -EFAULT;
+ if (val)
+ {
+ if (val < 1)
+ val = 1;
+ if (val > 1000)
+ val = 1000;
+ curr_timebase = val;
+ }
+ val = curr_timebase;
+ break;
+
+ case SNDCTL_TMR_TEMPO:
+ if (get_user(val, p))
+ return -EFAULT;
+ 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();
+ }
+ val = curr_tempo;
+ break;
+
+ case SNDCTL_SEQ_CTRLRATE:
+ if (get_user(val, p))
+ return -EFAULT;
+ if (val != 0) /* Can't change */
+ return -EINVAL;
+ val = ((curr_tempo * curr_timebase) + 30) / 60;
+ break;
+
+ case SNDCTL_SEQ_GETTIME:
+ val = curr_ticks;
+ break;
+
+ case SNDCTL_TMR_METRONOME:
+ default:
+ return -EINVAL;
+ }
+ return put_user(val, p);
+}
+
+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 =
+{
+ .owner = THIS_MODULE,
+ .info = {"Sound Timer", 0},
+ .priority = 1, /* Priority */
+ .devlink = 0, /* Local device link */
+ .open = timer_open,
+ .close = timer_close,
+ .event = timer_event,
+ .get_time = timer_get_time,
+ .ioctl = timer_ioctl,
+ .arm_timer = timer_arm
+};
+
+void sound_timer_interrupt(void)
+{
+ unsigned long flags;
+
+ if (!opened)
+ return;
+
+ tmr->tmr_restart(tmr->dev);
+
+ if (!tmr_running)
+ return;
+
+ spin_lock_irqsave(&lock,flags);
+ tmr_ctr++;
+ curr_ticks = ticks_offs + tmr2ticks(tmr_ctr);
+
+ if (curr_ticks >= next_event_time)
+ {
+ next_event_time = (unsigned long) -1;
+ sequencer_timer(0);
+ }
+ spin_unlock_irqrestore(&lock,flags);
+}
+EXPORT_SYMBOL(sound_timer_interrupt);
+
+void sound_timer_init(struct sound_lowlev_timer *t, char *name)
+{
+ int n;
+
+ if (initialized)
+ {
+ if (t->priority <= tmr->priority)
+ return; /* There is already a similar or better timer */
+ tmr = t;
+ return;
+ }
+ initialized = 1;
+ tmr = t;
+
+ n = sound_alloc_timerdev();
+ if (n == -1)
+ n = 0; /* Overwrite the system timer */
+ strlcpy(sound_timer.info.name, name, sizeof(sound_timer.info.name));
+ sound_timer_devs[n] = &sound_timer;
+}
+EXPORT_SYMBOL(sound_timer_init);
+
Code Review / kvmfornfv.git / blobdiff