diff options
Diffstat (limited to 'sound/oss/sys_timer.c')
| -rw-r--r-- | sound/oss/sys_timer.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/sound/oss/sys_timer.c b/sound/oss/sys_timer.c new file mode 100644 index 000000000..2226dda0e --- /dev/null +++ b/sound/oss/sys_timer.c @@ -0,0 +1,280 @@ +/* + * sound/oss/sys_timer.c + * + * The default timer for the Level 2 sequencer interface + * Uses the (1/HZ sec) timer of kernel. + */ +/* + * 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) + * Andrew Veliath : adapted tmr2ticks from level 1 sequencer (avoid overflow) + */ +#include <linux/spinlock.h> +#include "sound_config.h" + +static volatile int 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 void poll_def_tmr(unsigned long dummy); +static DEFINE_SPINLOCK(lock); +static DEFINE_TIMER(def_tmr, poll_def_tmr, 0, 0); + +static unsigned long +tmr2ticks(int tmr_value) +{ + /* + * Convert timer ticks to MIDI ticks + */ + + unsigned long tmp; + unsigned long scale; + + /* tmr_value (ticks per sec) * + 1000000 (usecs per sec) / HZ (ticks per sec) -=> usecs */ + tmp = tmr_value * (1000000 / HZ); + scale = (60 * 1000000) / (curr_tempo * curr_timebase); /* usecs per MIDI tick */ + return (tmp + scale / 2) / scale; +} + +static void +poll_def_tmr(unsigned long dummy) +{ + if (!opened) + return; + def_tmr.expires = (1) + jiffies; + add_timer(&def_tmr); + + if (!tmr_running) + return; + + spin_lock(&lock); + 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(&lock); +} + +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 +def_tmr_open(int dev, int mode) +{ + if (opened) + return -EBUSY; + + tmr_reset(); + curr_tempo = 60; + curr_timebase = 100; + opened = 1; + { + def_tmr.expires = (1) + jiffies; + add_timer(&def_tmr); + } + + return 0; +} + +static void +def_tmr_close(int dev) +{ + opened = tmr_running = 0; + del_timer(&def_tmr); +} + +static int +def_tmr_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; + break; + + case TMR_STOP: + tmr_running = 0; + break; + + case TMR_CONTINUE: + tmr_running = 1; + break; + + case TMR_TEMPO: + if (parm) + { + if (parm < 8) + parm = 8; + if (parm > 360) + parm = 360; + tmr_offs = tmr_ctr; + ticks_offs += tmr2ticks(tmr_ctr); + tmr_ctr = 0; + curr_tempo = parm; + } + break; + + case TMR_ECHO: + seq_copy_to_input(event, 8); + break; + + default:; + } + + return TIMER_NOT_ARMED; +} + +static unsigned long +def_tmr_get_time(int dev) +{ + if (!opened) + return 0; + + return curr_ticks; +} + +/* same as sound_timer.c:timer_ioctl!? */ +static int def_tmr_ioctl(int dev, unsigned int cmd, void __user *arg) +{ + int __user *p = arg; + int val; + + switch (cmd) { + case SNDCTL_TMR_SOURCE: + return __put_user(TMR_INTERNAL, p); + + 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; + } + return __put_user(curr_timebase, p); + + 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(); + } + return __put_user(curr_tempo, p); + + 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; + return __put_user(val, p); + + case SNDCTL_SEQ_GETTIME: + return __put_user(curr_ticks, p); + + case SNDCTL_TMR_METRONOME: + /* NOP */ + break; + + default:; + } + return -EINVAL; +} + +static void +def_tmr_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; +} + +struct sound_timer_operations default_sound_timer = +{ + .owner = THIS_MODULE, + .info = {"System clock", 0}, + .priority = 0, /* Priority */ + .devlink = 0, /* Local device link */ + .open = def_tmr_open, + .close = def_tmr_close, + .event = def_tmr_event, + .get_time = def_tmr_get_time, + .ioctl = def_tmr_ioctl, + .arm_timer = def_tmr_arm +}; |