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 32 33 /* 34 * create a write queue record 35 */ 36 struct seq_oss_writeq * 37 snd_seq_oss_writeq_new(struct seq_oss_devinfo *dp, int maxlen) 38 { 39 struct seq_oss_writeq *q; 40 struct snd_seq_client_pool pool; 41 42 if ((q = kzalloc(sizeof(*q), GFP_KERNEL)) == NULL) 43 return NULL; 44 q->dp = dp; 45 q->maxlen = maxlen; 46 spin_lock_init(&q->sync_lock); 47 q->sync_event_put = 0; 48 q->sync_time = 0; 49 init_waitqueue_head(&q->sync_sleep); 50 51 memset(&pool, 0, sizeof(pool)); 52 pool.client = dp->cseq; 53 pool.output_pool = maxlen; 54 pool.output_room = maxlen / 2; 55 56 snd_seq_oss_control(dp, SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, &pool); 57 58 return q; 59 } 60 61 /* 62 * delete the write queue 63 */ 64 void 65 snd_seq_oss_writeq_delete(struct seq_oss_writeq *q) 66 { 67 if (q) { 68 snd_seq_oss_writeq_clear(q); /* to be sure */ 69 kfree(q); 70 } 71 } 72 73 74 /* 75 * reset the write queue 76 */ 77 void 78 snd_seq_oss_writeq_clear(struct seq_oss_writeq *q) 79 { 80 struct snd_seq_remove_events reset; 81 82 memset(&reset, 0, sizeof(reset)); 83 reset.remove_mode = SNDRV_SEQ_REMOVE_OUTPUT; /* remove all */ 84 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_REMOVE_EVENTS, &reset); 85 86 /* wake up sleepers if any */ 87 snd_seq_oss_writeq_wakeup(q, 0); 88 } 89 90 /* 91 * wait until the write buffer has enough room 92 */ 93 int 94 snd_seq_oss_writeq_sync(struct seq_oss_writeq *q) 95 { 96 struct seq_oss_devinfo *dp = q->dp; 97 abstime_t time; 98 99 time = snd_seq_oss_timer_cur_tick(dp->timer); 100 if (q->sync_time >= time) 101 return 0; /* already finished */ 102 103 if (! q->sync_event_put) { 104 struct snd_seq_event ev; 105 union evrec *rec; 106 107 /* put echoback event */ 108 memset(&ev, 0, sizeof(ev)); 109 ev.flags = 0; 110 ev.type = SNDRV_SEQ_EVENT_ECHO; 111 ev.time.tick = time; 112 /* echo back to itself */ 113 snd_seq_oss_fill_addr(dp, &ev, dp->addr.client, dp->addr.port); 114 rec = (union evrec *)&ev.data; 115 rec->t.code = SEQ_SYNCTIMER; 116 rec->t.time = time; 117 q->sync_event_put = 1; 118 snd_seq_kernel_client_enqueue_blocking(dp->cseq, &ev, NULL, 0, 0); 119 } 120 121 wait_event_interruptible_timeout(q->sync_sleep, ! q->sync_event_put, HZ); 122 if (signal_pending(current)) 123 /* interrupted - return 0 to finish sync */ 124 q->sync_event_put = 0; 125 if (! q->sync_event_put || q->sync_time >= time) 126 return 0; 127 return 1; 128 } 129 130 /* 131 * wake up sync - echo event was catched 132 */ 133 void 134 snd_seq_oss_writeq_wakeup(struct seq_oss_writeq *q, abstime_t time) 135 { 136 unsigned long flags; 137 138 spin_lock_irqsave(&q->sync_lock, flags); 139 q->sync_time = time; 140 q->sync_event_put = 0; 141 wake_up(&q->sync_sleep); 142 spin_unlock_irqrestore(&q->sync_lock, flags); 143 } 144 145 146 /* 147 * return the unused pool size 148 */ 149 int 150 snd_seq_oss_writeq_get_free_size(struct seq_oss_writeq *q) 151 { 152 struct snd_seq_client_pool pool; 153 pool.client = q->dp->cseq; 154 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, &pool); 155 return pool.output_free; 156 } 157 158 159 /* 160 * set output threshold size from ioctl 161 */ 162 void 163 snd_seq_oss_writeq_set_output(struct seq_oss_writeq *q, int val) 164 { 165 struct snd_seq_client_pool pool; 166 pool.client = q->dp->cseq; 167 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_GET_CLIENT_POOL, &pool); 168 pool.output_room = val; 169 snd_seq_oss_control(q->dp, SNDRV_SEQ_IOCTL_SET_CLIENT_POOL, &pool); 170 } 171 172