LXR linux/sound/core/seq/oss/seq_oss

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * OSS compatible sequencer driver
   4 *
   5 * read/write/select interface to device file
   6 *
   7 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>
   8 */
   9
  10#include "seq_oss_device.h"
  11#include "seq_oss_readq.h"
  12#include "seq_oss_writeq.h"
  13#include "seq_oss_synth.h"
  14#include <sound/seq_oss_legacy.h>
  15#include "seq_oss_event.h"
  16#include "seq_oss_timer.h"
  17#include "../seq_clientmgr.h"
  18
  19
  20/*
  21 * protoypes
  22 */
  23static int insert_queue(struct seq_oss_devinfo *dp, union evrec *rec, struct file *opt);
  24
  25
  26/*
  27 * read interface
  28 */
  29
  30int
  31snd_seq_oss_read(struct seq_oss_devinfo *dp, char __user *buf, int count)
  32{
  33        struct seq_oss_readq *readq = dp->readq;
  34        int result = 0, err = 0;
  35        int ev_len;
  36        union evrec rec;
  37        unsigned long flags;
  38
  39        if (readq == NULL || ! is_read_mode(dp->file_mode))
  40                return -ENXIO;
  41
  42        while (count >= SHORT_EVENT_SIZE) {
  43                snd_seq_oss_readq_lock(readq, flags);
  44                err = snd_seq_oss_readq_pick(readq, &rec);
  45                if (err == -EAGAIN &&
  46                    !is_nonblock_mode(dp->file_mode) && result == 0) {
  47                        snd_seq_oss_readq_unlock(readq, flags);
  48                        snd_seq_oss_readq_wait(readq);
  49                        snd_seq_oss_readq_lock(readq, flags);
  50                        if (signal_pending(current))
  51                                err = -ERESTARTSYS;
  52                        else
  53                                err = snd_seq_oss_readq_pick(readq, &rec);
  54                }
  55                if (err < 0) {
  56                        snd_seq_oss_readq_unlock(readq, flags);
  57                        break;
  58                }
  59                ev_len = ev_length(&rec);
  60                if (ev_len < count) {
  61                        snd_seq_oss_readq_unlock(readq, flags);
  62                        break;
  63                }
  64                snd_seq_oss_readq_free(readq);
  65                snd_seq_oss_readq_unlock(readq, flags);
  66                if (copy_to_user(buf, &rec, ev_len)) {
  67                        err = -EFAULT;
  68                        break;
  69                }
  70                result += ev_len;
  71                buf += ev_len;
  72                count -= ev_len;
  73        }
  74        return result > 0 ? result : err;
  75}
  76
  77
  78/*
  79 * write interface
  80 */
  81
  82int
  83snd_seq_oss_write(struct seq_oss_devinfo *dp, const char __user *buf, int count, struct file *opt)
  84{
  85        int result = 0, err = 0;
  86        int ev_size, fmt;
  87        union evrec rec;
  88
  89        if (! is_write_mode(dp->file_mode) || dp->writeq == NULL)
  90                return -ENXIO;
  91
  92        while (count >= SHORT_EVENT_SIZE) {
  93                if (copy_from_user(&rec, buf, SHORT_EVENT_SIZE)) {
  94                        err = -EFAULT;
  95                        break;
  96                }
  97                if (rec.s.code == SEQ_FULLSIZE) {
  98                        /* load patch */
  99                        if (result > 0) {
 100                                err = -EINVAL;
 101                                break;
 102                        }
 103                        fmt = (*(unsigned short *)rec.c) & 0xffff;
 104                        /* FIXME the return value isn't correct */
 105                        return snd_seq_oss_synth_load_patch(dp, rec.s.dev,
 106                                                            fmt, buf, 0, count);
 107                }
 108                if (ev_is_long(&rec)) {
 109                        /* extended code */
 110                        if (rec.s.code == SEQ_EXTENDED &&
 111                            dp->seq_mode == SNDRV_SEQ_OSS_MODE_MUSIC) {
 112                                err = -EINVAL;
 113                                break;
 114                        }
 115                        ev_size = LONG_EVENT_SIZE;
 116                        if (count < ev_size)
 117                                break;
 118                        /* copy the reset 4 bytes */
 119                        if (copy_from_user(rec.c + SHORT_EVENT_SIZE,
 120                                           buf + SHORT_EVENT_SIZE,
 121                                           LONG_EVENT_SIZE - SHORT_EVENT_SIZE)) {
 122                                err = -EFAULT;
 123                                break;
 124                        }
 125                } else {
 126                        /* old-type code */
 127                        if (dp->seq_mode == SNDRV_SEQ_OSS_MODE_MUSIC) {
 128                                err = -EINVAL;
 129                                break;
 130                        }
 131                        ev_size = SHORT_EVENT_SIZE;
 132                }
 133
 134                /* insert queue */
 135                err = insert_queue(dp, &rec, opt);
 136                if (err < 0)
 137                        break;
 138
 139                result += ev_size;
 140                buf += ev_size;
 141                count -= ev_size;
 142        }
 143        return result > 0 ? result : err;
 144}
 145
 146
 147/*
 148 * insert event record to write queue
 149 * return: 0 = OK, non-zero = NG
 150 */
 151static int
 152insert_queue(struct seq_oss_devinfo *dp, union evrec *rec, struct file *opt)
 153{
 154        int rc = 0;
 155        struct snd_seq_event event;
 156
 157        /* if this is a timing event, process the current time */
 158        if (snd_seq_oss_process_timer_event(dp->timer, rec))
 159                return 0; /* no need to insert queue */
 160
 161        /* parse this event */
 162        memset(&event, 0, sizeof(event));
 163        /* set dummy -- to be sure */
 164        event.type = SNDRV_SEQ_EVENT_NOTEOFF;
 165        snd_seq_oss_fill_addr(dp, &event, dp->addr.client, dp->addr.port);
 166
 167        if (snd_seq_oss_process_event(dp, rec, &event))
 168                return 0; /* invalid event - no need to insert queue */
 169
 170        event.time.tick = snd_seq_oss_timer_cur_tick(dp->timer);
 171        if (dp->timer->realtime || !dp->timer->running)
 172                snd_seq_oss_dispatch(dp, &event, 0, 0);
 173        else
 174                rc = snd_seq_kernel_client_enqueue(dp->cseq, &event, opt,
 175                                                   !is_nonblock_mode(dp->file_mode));
 176        return rc;
 177}
 178                
 179
 180/*
 181 * select / poll
 182 */
 183  
 184__poll_t
 185snd_seq_oss_poll(struct seq_oss_devinfo *dp, struct file *file, poll_table * wait)
 186{
 187        __poll_t mask = 0;
 188
 189        /* input */
 190        if (dp->readq && is_read_mode(dp->file_mode)) {
 191                if (snd_seq_oss_readq_poll(dp->readq, file, wait))
 192                        mask |= EPOLLIN | EPOLLRDNORM;
 193        }
 194
 195        /* output */
 196        if (dp->writeq && is_write_mode(dp->file_mode)) {
 197                if (snd_seq_kernel_client_write_poll(dp->cseq, file, wait))
 198                        mask |= EPOLLOUT | EPOLLWRNORM;
 199        }
 200        return mask;
 201}
 202