1/* 2 * OSS compatible sequencer driver 3 * 4 * seq_oss_readq.c - MIDI input queue 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_readq.h" 24#include "seq_oss_event.h" 25#include <sound/seq_oss_legacy.h> 26#include "../seq_lock.h" 27#include <linux/wait.h> 28#include <linux/slab.h> 29 30/* 31 * constants 32 */ 33//#define SNDRV_SEQ_OSS_MAX_TIMEOUT (unsigned long)(-1) 34#define SNDRV_SEQ_OSS_MAX_TIMEOUT (HZ * 3600) 35 36 37/* 38 * prototypes 39 */ 40 41 42/* 43 * create a read queue 44 */ 45struct seq_oss_readq * 46snd_seq_oss_readq_new(struct seq_oss_devinfo *dp, int maxlen) 47{ 48 struct seq_oss_readq *q; 49 50 if ((q = kzalloc(sizeof(*q), GFP_KERNEL)) == NULL) { 51 snd_printk(KERN_ERR "can't malloc read queue\n"); 52 return NULL; 53 } 54 55 if ((q->q = kcalloc(maxlen, sizeof(union evrec), GFP_KERNEL)) == NULL) { 56 snd_printk(KERN_ERR "can't malloc read queue buffer\n"); 57 kfree(q); 58 return NULL; 59 } 60 61 q->maxlen = maxlen; 62 q->qlen = 0; 63 q->head = q->tail = 0; 64 init_waitqueue_head(&q->midi_sleep); 65 spin_lock_init(&q->lock); 66 q->pre_event_timeout = SNDRV_SEQ_OSS_MAX_TIMEOUT; 67 q->input_time = (unsigned long)-1; 68 69 return q; 70} 71 72/* 73 * delete the read queue 74 */ 75void 76snd_seq_oss_readq_delete(struct seq_oss_readq *q) 77{ 78 if (q) { 79 kfree(q->q); 80 kfree(q); 81 } 82} 83 84/* 85 * reset the read queue 86 */ 87void 88snd_seq_oss_readq_clear(struct seq_oss_readq *q) 89{ 90 if (q->qlen) { 91 q->qlen = 0; 92 q->head = q->tail = 0; 93 } 94 /* if someone sleeping, wake'em up */ 95 if (waitqueue_active(&q->midi_sleep)) 96 wake_up(&q->midi_sleep); 97 q->input_time = (unsigned long)-1; 98} 99 100/* 101 * put a midi byte 102 */ 103int 104snd_seq_oss_readq_puts(struct seq_oss_readq *q, int dev, unsigned char *data, int len) 105{ 106 union evrec rec; 107 int result; 108 109 memset(&rec, 0, sizeof(rec)); 110 rec.c[0] = SEQ_MIDIPUTC; 111 rec.c[2] = dev; 112 113 while (len-- > 0) { 114 rec.c[1] = *data++; 115 result = snd_seq_oss_readq_put_event(q, &rec); 116 if (result < 0) 117 return result; 118 } 119 return 0; 120} 121 122/* 123 * copy an event to input queue: 124 * return zero if enqueued 125 */ 126int 127snd_seq_oss_readq_put_event(struct seq_oss_readq *q, union evrec *ev) 128{ 129 unsigned long flags; 130 131 spin_lock_irqsave(&q->lock, flags); 132 if (q->qlen >= q->maxlen - 1) { 133 spin_unlock_irqrestore(&q->lock, flags); 134 return -ENOMEM; 135 } 136 137 memcpy(&q->q[q->tail], ev, sizeof(*ev)); 138 q->tail = (q->tail + 1) % q->maxlen; 139 q->qlen++; 140 141 /* wake up sleeper */ 142 if (waitqueue_active(&q->midi_sleep)) 143 wake_up(&q->midi_sleep); 144 145 spin_unlock_irqrestore(&q->lock, flags); 146 147 return 0; 148} 149 150 151/* 152 * pop queue 153 * caller must hold lock 154 */ 155int 156snd_seq_oss_readq_pick(struct seq_oss_readq *q, union evrec *rec) 157{ 158 if (q->qlen == 0) 159 return -EAGAIN; 160 memcpy(rec, &q->q[q->head], sizeof(*rec)); 161 return 0; 162} 163 164/* 165 * sleep until ready 166 */ 167void 168snd_seq_oss_readq_wait(struct seq_oss_readq *q) 169{ 170 wait_event_interruptible_timeout(q->midi_sleep, 171 (q->qlen > 0 || q->head == q->tail), 172 q->pre_event_timeout); 173} 174 175/* 176 * drain one record 177 * caller must hold lock 178 */ 179void 180snd_seq_oss_readq_free(struct seq_oss_readq *q) 181{ 182 if (q->qlen > 0) { 183 q->head = (q->head + 1) % q->maxlen; 184 q->qlen--; 185 } 186} 187 188/* 189 * polling/select: 190 * return non-zero if readq is not empty. 191 */ 192unsigned int 193snd_seq_oss_readq_poll(struct seq_oss_readq *q, struct file *file, poll_table *wait) 194{ 195 poll_wait(file, &q->midi_sleep, wait); 196 return q->qlen; 197} 198 199/* 200 * put a timestamp 201 */ 202int 203snd_seq_oss_readq_put_timestamp(struct seq_oss_readq *q, unsigned long curt, int seq_mode) 204{ 205 if (curt != q->input_time) { 206 union evrec rec; 207 memset(&rec, 0, sizeof(rec)); 208 switch (seq_mode) { 209 case SNDRV_SEQ_OSS_MODE_SYNTH: 210 rec.echo = (curt << 8) | SEQ_WAIT; 211 snd_seq_oss_readq_put_event(q, &rec); 212 break; 213 case SNDRV_SEQ_OSS_MODE_MUSIC: 214 rec.t.code = EV_TIMING; 215 rec.t.cmd = TMR_WAIT_ABS; 216 rec.t.time = curt; 217 snd_seq_oss_readq_put_event(q, &rec); 218 break; 219 } 220 q->input_time = curt; 221 } 222 return 0; 223} 224 225 226#ifdef CONFIG_PROC_FS 227/* 228 * proc interface 229 */ 230void 231snd_seq_oss_readq_info_read(struct seq_oss_readq *q, struct snd_info_buffer *buf) 232{ 233 snd_iprintf(buf, " read queue [%s] length = %d : tick = %ld\n", 234 (waitqueue_active(&q->midi_sleep) ? "sleeping":"running"), 235 q->qlen, q->input_time); 236} 237#endif /* CONFIG_PROC_FS */ 238