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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * OSS compatible sequencer driver4 *5 * Timer control routines6 *7 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>8 */9 10#include "seq_oss_timer.h"11#include "seq_oss_event.h"12#include <sound/seq_oss_legacy.h>13#include <linux/slab.h>14 15/*16 */17#define MIN_OSS_TEMPO 818#define MAX_OSS_TEMPO 36019#define MIN_OSS_TIMEBASE 120#define MAX_OSS_TIMEBASE 100021 22/*23 */24static void calc_alsa_tempo(struct seq_oss_timer *timer);25static int send_timer_event(struct seq_oss_devinfo *dp, int type, int value);26 27 28/*29 * create and register a new timer.30 * if queue is not started yet, start it.31 */32struct seq_oss_timer *33snd_seq_oss_timer_new(struct seq_oss_devinfo *dp)34{35 struct seq_oss_timer *rec;36 37 rec = kzalloc(sizeof(*rec), GFP_KERNEL);38 if (rec == NULL)39 return NULL;40 41 rec->dp = dp;42 rec->cur_tick = 0;43 rec->realtime = 0;44 rec->running = 0;45 rec->oss_tempo = 60;46 rec->oss_timebase = 100;47 calc_alsa_tempo(rec);48 49 return rec;50}51 52 53/*54 * delete timer.55 * if no more timer exists, stop the queue.56 */57void58snd_seq_oss_timer_delete(struct seq_oss_timer *rec)59{60 if (rec) {61 snd_seq_oss_timer_stop(rec);62 kfree(rec);63 }64}65 66 67/*68 * process one timing event69 * return 1 : event proceseed -- skip this event70 * 0 : not a timer event -- enqueue this event71 */72int73snd_seq_oss_process_timer_event(struct seq_oss_timer *rec, union evrec *ev)74{75 abstime_t parm = ev->t.time;76 77 if (ev->t.code == EV_TIMING) {78 switch (ev->t.cmd) {79 case TMR_WAIT_REL:80 parm += rec->cur_tick;81 rec->realtime = 0;82 fallthrough;83 case TMR_WAIT_ABS:84 if (parm == 0) {85 rec->realtime = 1;86 } else if (parm >= rec->cur_tick) {87 rec->realtime = 0;88 rec->cur_tick = parm;89 }90 return 1; /* skip this event */91 92 case TMR_START:93 snd_seq_oss_timer_start(rec);94 return 1;95 96 }97 } else if (ev->s.code == SEQ_WAIT) {98 /* time = from 1 to 3 bytes */99 parm = (ev->echo >> 8) & 0xffffff;100 if (parm > rec->cur_tick) {101 /* set next event time */102 rec->cur_tick = parm;103 rec->realtime = 0;104 }105 return 1;106 }107 108 return 0;109}110 111 112/*113 * convert tempo units114 */115static void116calc_alsa_tempo(struct seq_oss_timer *timer)117{118 timer->tempo = (60 * 1000000) / timer->oss_tempo;119 timer->ppq = timer->oss_timebase;120}121 122 123/*124 * dispatch a timer event125 */126static int127send_timer_event(struct seq_oss_devinfo *dp, int type, int value)128{129 struct snd_seq_event ev;130 131 memset(&ev, 0, sizeof(ev));132 ev.type = type;133 ev.source.client = dp->cseq;134 ev.source.port = 0;135 ev.dest.client = SNDRV_SEQ_CLIENT_SYSTEM;136 ev.dest.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;137 ev.queue = dp->queue;138 ev.data.queue.queue = dp->queue;139 ev.data.queue.param.value = value;140 return snd_seq_kernel_client_dispatch(dp->cseq, &ev, 1, 0);141}142 143/*144 * set queue tempo and start queue145 */146int147snd_seq_oss_timer_start(struct seq_oss_timer *timer)148{149 struct seq_oss_devinfo *dp = timer->dp;150 struct snd_seq_queue_tempo tmprec;151 152 if (timer->running)153 snd_seq_oss_timer_stop(timer);154 155 memset(&tmprec, 0, sizeof(tmprec));156 tmprec.queue = dp->queue;157 tmprec.ppq = timer->ppq;158 tmprec.tempo = timer->tempo;159 snd_seq_set_queue_tempo(dp->cseq, &tmprec);160 161 send_timer_event(dp, SNDRV_SEQ_EVENT_START, 0);162 timer->running = 1;163 timer->cur_tick = 0;164 return 0;165}166 167 168/*169 * stop queue170 */171int172snd_seq_oss_timer_stop(struct seq_oss_timer *timer)173{174 if (! timer->running)175 return 0;176 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_STOP, 0);177 timer->running = 0;178 return 0;179}180 181 182/*183 * continue queue184 */185int186snd_seq_oss_timer_continue(struct seq_oss_timer *timer)187{188 if (timer->running)189 return 0;190 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_CONTINUE, 0);191 timer->running = 1;192 return 0;193}194 195 196/*197 * change queue tempo198 */199int200snd_seq_oss_timer_tempo(struct seq_oss_timer *timer, int value)201{202 if (value < MIN_OSS_TEMPO)203 value = MIN_OSS_TEMPO;204 else if (value > MAX_OSS_TEMPO)205 value = MAX_OSS_TEMPO;206 timer->oss_tempo = value;207 calc_alsa_tempo(timer);208 if (timer->running)209 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_TEMPO, timer->tempo);210 return 0;211}212 213 214/*215 * ioctls216 */217int218snd_seq_oss_timer_ioctl(struct seq_oss_timer *timer, unsigned int cmd, int __user *arg)219{220 int value;221 222 if (cmd == SNDCTL_SEQ_CTRLRATE) {223 /* if *arg == 0, just return the current rate */224 if (get_user(value, arg))225 return -EFAULT;226 if (value)227 return -EINVAL;228 value = ((timer->oss_tempo * timer->oss_timebase) + 30) / 60;229 return put_user(value, arg) ? -EFAULT : 0;230 }231 232 if (timer->dp->seq_mode == SNDRV_SEQ_OSS_MODE_SYNTH)233 return 0;234 235 switch (cmd) {236 case SNDCTL_TMR_START:237 return snd_seq_oss_timer_start(timer);238 case SNDCTL_TMR_STOP:239 return snd_seq_oss_timer_stop(timer);240 case SNDCTL_TMR_CONTINUE:241 return snd_seq_oss_timer_continue(timer);242 case SNDCTL_TMR_TEMPO:243 if (get_user(value, arg))244 return -EFAULT;245 return snd_seq_oss_timer_tempo(timer, value);246 case SNDCTL_TMR_TIMEBASE:247 if (get_user(value, arg))248 return -EFAULT;249 if (value < MIN_OSS_TIMEBASE)250 value = MIN_OSS_TIMEBASE;251 else if (value > MAX_OSS_TIMEBASE)252 value = MAX_OSS_TIMEBASE;253 timer->oss_timebase = value;254 calc_alsa_tempo(timer);255 return 0;256 257 case SNDCTL_TMR_METRONOME:258 case SNDCTL_TMR_SELECT:259 case SNDCTL_TMR_SOURCE:260 /* not supported */261 return 0;262 }263 return 0;264}265