1 /* 2 * OSS compatible sequencer driver 3 * 4 * seq_oss_writeq.c - write queue and sync 5 * 6 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 #include "seq_oss_writeq.h" 24 #include "seq_oss_event.h" 25 #include "seq_oss_timer.h" 26 #include <sound/seq_oss_legacy.h> 27 #include "../seq_lock.h" 28 #include "../seq_clientmgr.h" 29 #include <linux/wait.h> 30 #include <linux/slab.h> 31 #include <linux/sched/signal.h> 32 33 34 /* 35 * create a write queue record 36 */ 37 struct seq_oss_writeq * 38 snd_seq_oss_writeq_new(struct seq_oss_devinfo *dp, int maxlen) 39 { 40 struct seq_oss_writeq *q; 41 struct snd_seq_client_pool pool; 42 43 if ((q = kzalloc(sizeof(*q), GFP_KERNEL)) == NULL) 44 return NULL; 45 q->dp = dp; 46 q->maxlen = maxlen; 47 spin_lock_init(&q->sync_lock); 48 q->sync_event_put = 0; 49 q->sync_time = 0; 50 init_waitqueue_head(&q->sync_sleep); 51 52 memset(&pool, 0, sizeof(pool)); 53 pool.client = dp->cseq; 54 pool.output_pool = maxlen; 55 pool.output_room = maxlen / 2; 56 57 snd_seq_oss_control(dp, SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, &pool); 58 59 return q; 60 } 61 62 /* 63 * delete the write queue 64 */ 65 void 66 snd_seq_oss_writeq_delete(struct seq_oss_writeq *q) 67 { 68 if (q) { 69 snd_seq_oss_writeq_clear(q); /* to be sure */ 70 kfree(q); 71 } 72 } 73 74 75 /* 76 * reset the write queue 77 */ 78 void 79 snd_seq_oss_writeq_clear(struct seq_oss_writeq *q) 80 { 81 struct snd_seq_remove_events reset; 82 83 memset(&reset, 0, sizeof(reset)); 84 reset.remove_mode = SNDRV_SEQ_REMOVE_OUTPUT; /* remove all */ 85 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_REMOVE_EVENTS, &reset); 86 87 /* wake up sleepers if any */ 88 snd_seq_oss_writeq_wakeup(q, 0); 89 } 90 91 /* 92 * wait until the write buffer has enough room 93 */ 94 int 95 snd_seq_oss_writeq_sync(struct seq_oss_writeq *q) 96 { 97 struct seq_oss_devinfo *dp = q->dp; 98 abstime_t time; 99 100 time = snd_seq_oss_timer_cur_tick(dp->timer); 101 if (q->sync_time >= time) 102 return 0; /* already finished */ 103 104 if (! q->sync_event_put) { 105 struct snd_seq_event ev; 106 union evrec *rec; 107 108 /* put echoback event */ 109 memset(&ev, 0, sizeof(ev)); 110 ev.flags = 0; 111 ev.type = SNDRV_SEQ_EVENT_ECHO; 112 ev.time.tick = time; 113 /* echo back to itself */ 114 snd_seq_oss_fill_addr(dp, &ev, dp->addr.client, dp->addr.port); 115 rec = (union evrec *)&ev.data; 116 rec->t.code = SEQ_SYNCTIMER; 117 rec->t.time = time; 118 q->sync_event_put = 1; 119 snd_seq_kernel_client_enqueue_blocking(dp->cseq, &ev, NULL, 0, 0); 120 } 121 122 wait_event_interruptible_timeout(q->sync_sleep, ! q->sync_event_put, HZ); 123 if (signal_pending(current)) 124 /* interrupted - return 0 to finish sync */ 125 q->sync_event_put = 0; 126 if (! q->sync_event_put || q->sync_time >= time) 127 return 0; 128 return 1; 129 } 130 131 /* 132 * wake up sync - echo event was catched 133 */ 134 void 135 snd_seq_oss_writeq_wakeup(struct seq_oss_writeq *q, abstime_t time) 136 { 137 unsigned long flags; 138 139 spin_lock_irqsave(&q->sync_lock, flags); 140 q->sync_time = time; 141 q->sync_event_put = 0; 142 wake_up(&q->sync_sleep); 143 spin_unlock_irqrestore(&q->sync_lock, flags); 144 } 145 146 147 /* 148 * return the unused pool size 149 */ 150 int 151 snd_seq_oss_writeq_get_free_size(struct seq_oss_writeq *q) 152 { 153 struct snd_seq_client_pool pool; 154 pool.client = q->dp->cseq; 155 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, &pool); 156 return pool.output_free; 157 } 158 159 160 /* 161 * set output threshold size from ioctl 162 */ 163 void 164 snd_seq_oss_writeq_set_output(struct seq_oss_writeq *q, int val) 165 { 166 struct snd_seq_client_pool pool; 167 pool.client = q->dp->cseq; 168 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, &pool); 169 pool.output_room = val; 170 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, &pool); 171 } 172 173