seq_oss_rw.c (4586B)
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}