/* * 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 unsigned int 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 longtmr2ticks(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 voidpoll_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 voidtmr_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 intdef_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 voiddef_tmr_close(int dev){	opened = tmr_running = 0;	del_timer(&def_tmr);} static intdef_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 longdef_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 voiddef_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};