// SPDX-License-Identifier: GPL-2.0-or-later/* * OSS compatible sequencer driver * * Timer control routines * * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de> */ #include "seq_oss_timer.h"#include "seq_oss_event.h"#include <sound/seq_oss_legacy.h>#include <linux/slab.h> /* */#define MIN_OSS_TEMPO		8#define MAX_OSS_TEMPO		360#define MIN_OSS_TIMEBASE	1#define MAX_OSS_TIMEBASE	1000 /* */static void calc_alsa_tempo(struct seq_oss_timer *timer);static int send_timer_event(struct seq_oss_devinfo *dp, int type, int value);  /* * create and register a new timer. * if queue is not started yet, start it. */struct seq_oss_timer *snd_seq_oss_timer_new(struct seq_oss_devinfo *dp){	struct seq_oss_timer *rec; 	rec = kzalloc_obj(*rec);	if (rec == NULL)		return NULL; 	rec->dp = dp;	rec->cur_tick = 0;	rec->realtime = 0;	rec->running = 0;	rec->oss_tempo = 60;	rec->oss_timebase = 100;	calc_alsa_tempo(rec); 	return rec;}  /* * delete timer. * if no more timer exists, stop the queue. */voidsnd_seq_oss_timer_delete(struct seq_oss_timer *rec){	if (rec) {		snd_seq_oss_timer_stop(rec);		kfree(rec);	}}  /* * process one timing event * return 1 : event proceseed -- skip this event *        0 : not a timer event -- enqueue this event */intsnd_seq_oss_process_timer_event(struct seq_oss_timer *rec, union evrec *ev){	abstime_t parm = ev->t.time; 	if (ev->t.code == EV_TIMING) {		switch (ev->t.cmd) {		case TMR_WAIT_REL:			parm += rec->cur_tick;			rec->realtime = 0;			fallthrough;		case TMR_WAIT_ABS:			if (parm == 0) {				rec->realtime = 1;			} else if (parm >= rec->cur_tick) {				rec->realtime = 0;				rec->cur_tick = parm;			}			return 1;	/* skip this event */					case TMR_START:			snd_seq_oss_timer_start(rec);			return 1; 		}	} else if (ev->s.code == SEQ_WAIT) {		/* time = from 1 to 3 bytes */		parm = (ev->echo >> 8) & 0xffffff;		if (parm > rec->cur_tick) {			/* set next event time */			rec->cur_tick = parm;			rec->realtime = 0;		}		return 1;	} 	return 0;}  /* * convert tempo units */static voidcalc_alsa_tempo(struct seq_oss_timer *timer){	timer->tempo = (60 * 1000000) / timer->oss_tempo;	timer->ppq = timer->oss_timebase;}  /* * dispatch a timer event */static intsend_timer_event(struct seq_oss_devinfo *dp, int type, int value){	struct snd_seq_event ev; 	memset(&ev, 0, sizeof(ev));	ev.type = type;	ev.source.client = dp->cseq;	ev.source.port = 0;	ev.dest.client = SNDRV_SEQ_CLIENT_SYSTEM;	ev.dest.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;	ev.queue = dp->queue;	ev.data.queue.queue = dp->queue;	ev.data.queue.param.value = value;	return snd_seq_kernel_client_dispatch(dp->cseq, &ev, 1, 0);} /* * set queue tempo and start queue */intsnd_seq_oss_timer_start(struct seq_oss_timer *timer){	struct seq_oss_devinfo *dp = timer->dp;	struct snd_seq_queue_tempo tmprec; 	if (timer->running)		snd_seq_oss_timer_stop(timer); 	memset(&tmprec, 0, sizeof(tmprec));	tmprec.queue = dp->queue;	tmprec.ppq = timer->ppq;	tmprec.tempo = timer->tempo;	snd_seq_set_queue_tempo(dp->cseq, &tmprec); 	send_timer_event(dp, SNDRV_SEQ_EVENT_START, 0);	timer->running = 1;	timer->cur_tick = 0;	return 0;}  /* * stop queue */intsnd_seq_oss_timer_stop(struct seq_oss_timer *timer){	if (! timer->running)		return 0;	send_timer_event(timer->dp, SNDRV_SEQ_EVENT_STOP, 0);	timer->running = 0;	return 0;}  /* * continue queue */intsnd_seq_oss_timer_continue(struct seq_oss_timer *timer){	if (timer->running)		return 0;	send_timer_event(timer->dp, SNDRV_SEQ_EVENT_CONTINUE, 0);	timer->running = 1;	return 0;}  /* * change queue tempo */intsnd_seq_oss_timer_tempo(struct seq_oss_timer *timer, int value){	if (value < MIN_OSS_TEMPO)		value = MIN_OSS_TEMPO;	else if (value > MAX_OSS_TEMPO)		value = MAX_OSS_TEMPO;	timer->oss_tempo = value;	calc_alsa_tempo(timer);	if (timer->running)		send_timer_event(timer->dp, SNDRV_SEQ_EVENT_TEMPO, timer->tempo);	return 0;}  /* * ioctls */intsnd_seq_oss_timer_ioctl(struct seq_oss_timer *timer, unsigned int cmd, int __user *arg){	int value; 	if (cmd == SNDCTL_SEQ_CTRLRATE) {		/* if *arg == 0, just return the current rate */		if (get_user(value, arg))			return -EFAULT;		if (value)			return -EINVAL;		value = ((timer->oss_tempo * timer->oss_timebase) + 30) / 60;		return put_user(value, arg) ? -EFAULT : 0;	} 	if (timer->dp->seq_mode == SNDRV_SEQ_OSS_MODE_SYNTH)		return 0; 	switch (cmd) {	case SNDCTL_TMR_START:		return snd_seq_oss_timer_start(timer);	case SNDCTL_TMR_STOP:		return snd_seq_oss_timer_stop(timer);	case SNDCTL_TMR_CONTINUE:		return snd_seq_oss_timer_continue(timer);	case SNDCTL_TMR_TEMPO:		if (get_user(value, arg))			return -EFAULT;		return snd_seq_oss_timer_tempo(timer, value);	case SNDCTL_TMR_TIMEBASE:		if (get_user(value, arg))			return -EFAULT;		if (value < MIN_OSS_TIMEBASE)			value = MIN_OSS_TIMEBASE;		else if (value > MAX_OSS_TIMEBASE)			value = MAX_OSS_TIMEBASE;		timer->oss_timebase = value;		calc_alsa_tempo(timer);		return 0; 	case SNDCTL_TMR_METRONOME:	case SNDCTL_TMR_SELECT:	case SNDCTL_TMR_SOURCE:		/* not supported */		return 0;	}	return 0;}