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 * open/close and reset interface
   6 *
   7 * Copyright (C) 1998-1999 Takashi Iwai <tiwai@suse.de>
   8 */
   9
  10#include "seq_oss_device.h"
  11#include "seq_oss_synth.h"
  12#include "seq_oss_midi.h"
  13#include "seq_oss_writeq.h"
  14#include "seq_oss_readq.h"
  15#include "seq_oss_timer.h"
  16#include "seq_oss_event.h"
  17#include <linux/init.h>
  18#include <linux/export.h>
  19#include <linux/moduleparam.h>
  20#include <linux/slab.h>
  21#include <linux/workqueue.h>
  22
  23/*
  24 * common variables
  25 */
  26static int maxqlen = SNDRV_SEQ_OSS_MAX_QLEN;
  27module_param(maxqlen, int, 0444);
  28MODULE_PARM_DESC(maxqlen, "maximum queue length");
  29
  30static int system_client = -1; /* ALSA sequencer client number */
  31static int system_port = -1;
  32
  33static int num_clients;
  34static struct seq_oss_devinfo *client_table[SNDRV_SEQ_OSS_MAX_CLIENTS];
  35
  36
  37/*
  38 * prototypes
  39 */
  40static int receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop);
  41static int translate_mode(struct file *file);
  42static int create_port(struct seq_oss_devinfo *dp);
  43static int delete_port(struct seq_oss_devinfo *dp);
  44static int alloc_seq_queue(struct seq_oss_devinfo *dp);
  45static int delete_seq_queue(int queue);
  46static void free_devinfo(void *private);
  47
  48#define call_ctl(type,rec) snd_seq_kernel_client_ctl(system_client, type, rec)
  49
  50
  51/* call snd_seq_oss_midi_lookup_ports() asynchronously */
  52static void async_call_lookup_ports(struct work_struct *work)
  53{
  54        snd_seq_oss_midi_lookup_ports(system_client);
  55}
  56
  57static DECLARE_WORK(async_lookup_work, async_call_lookup_ports);
  58
  59/*
  60 * create sequencer client for OSS sequencer
  61 */
  62int __init
  63snd_seq_oss_create_client(void)
  64{
  65        int rc;
  66        struct snd_seq_port_info *port;
  67        struct snd_seq_port_callback port_callback;
  68
  69        port = kzalloc(sizeof(*port), GFP_KERNEL);
  70        if (!port) {
  71                rc = -ENOMEM;
  72                goto __error;
  73        }
  74
  75        /* create ALSA client */
  76        rc = snd_seq_create_kernel_client(NULL, SNDRV_SEQ_CLIENT_OSS,
  77                                          "OSS sequencer");
  78        if (rc < 0)
  79                goto __error;
  80
  81        system_client = rc;
  82
  83        /* create announcement receiver port */
  84        strcpy(port->name, "Receiver");
  85        port->addr.client = system_client;
  86        port->capability = SNDRV_SEQ_PORT_CAP_WRITE; /* receive only */
  87        port->type = 0;
  88
  89        memset(&port_callback, 0, sizeof(port_callback));
  90        /* don't set port_callback.owner here. otherwise the module counter
  91         * is incremented and we can no longer release the module..
  92         */
  93        port_callback.event_input = receive_announce;
  94        port->kernel = &port_callback;
  95        
  96        if (call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, port) >= 0) {
  97                struct snd_seq_port_subscribe subs;
  98
  99                system_port = port->addr.port;
 100                memset(&subs, 0, sizeof(subs));
 101                subs.sender.client = SNDRV_SEQ_CLIENT_SYSTEM;
 102                subs.sender.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
 103                subs.dest.client = system_client;
 104                subs.dest.port = system_port;
 105                call_ctl(SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, &subs);
 106        }
 107        rc = 0;
 108
 109        /* look up midi devices */
 110        schedule_work(&async_lookup_work);
 111
 112 __error:
 113        kfree(port);
 114        return rc;
 115}
 116
 117
 118/*
 119 * receive annoucement from system port, and check the midi device
 120 */
 121static int
 122receive_announce(struct snd_seq_event *ev, int direct, void *private, int atomic, int hop)
 123{
 124        struct snd_seq_port_info pinfo;
 125
 126        if (atomic)
 127                return 0; /* it must not happen */
 128
 129        switch (ev->type) {
 130        case SNDRV_SEQ_EVENT_PORT_START:
 131        case SNDRV_SEQ_EVENT_PORT_CHANGE:
 132                if (ev->data.addr.client == system_client)
 133                        break; /* ignore myself */
 134                memset(&pinfo, 0, sizeof(pinfo));
 135                pinfo.addr = ev->data.addr;
 136                if (call_ctl(SNDRV_SEQ_IOCTL_GET_PORT_INFO, &pinfo) >= 0)
 137                        snd_seq_oss_midi_check_new_port(&pinfo);
 138                break;
 139
 140        case SNDRV_SEQ_EVENT_PORT_EXIT:
 141                if (ev->data.addr.client == system_client)
 142                        break; /* ignore myself */
 143                snd_seq_oss_midi_check_exit_port(ev->data.addr.client,
 144                                                ev->data.addr.port);
 145                break;
 146        }
 147        return 0;
 148}
 149
 150
 151/*
 152 * delete OSS sequencer client
 153 */
 154int
 155snd_seq_oss_delete_client(void)
 156{
 157        cancel_work_sync(&async_lookup_work);
 158        if (system_client >= 0)
 159                snd_seq_delete_kernel_client(system_client);
 160
 161        snd_seq_oss_midi_clear_all();
 162
 163        return 0;
 164}
 165
 166
 167/*
 168 * open sequencer device
 169 */
 170int
 171snd_seq_oss_open(struct file *file, int level)
 172{
 173        int i, rc;
 174        struct seq_oss_devinfo *dp;
 175
 176        dp = kzalloc(sizeof(*dp), GFP_KERNEL);
 177        if (!dp)
 178                return -ENOMEM;
 179
 180        dp->cseq = system_client;
 181        dp->port = -1;
 182        dp->queue = -1;
 183
 184        for (i = 0; i < SNDRV_SEQ_OSS_MAX_CLIENTS; i++) {
 185                if (client_table[i] == NULL)
 186                        break;
 187        }
 188
 189        dp->index = i;
 190        if (i >= SNDRV_SEQ_OSS_MAX_CLIENTS) {
 191                pr_debug("ALSA: seq_oss: too many applications\n");
 192                rc = -ENOMEM;
 193                goto _error;
 194        }
 195
 196        /* look up synth and midi devices */
 197        snd_seq_oss_synth_setup(dp);
 198        snd_seq_oss_midi_setup(dp);
 199
 200        if (dp->synth_opened == 0 && dp->max_mididev == 0) {
 201                /* pr_err("ALSA: seq_oss: no device found\n"); */
 202                rc = -ENODEV;
 203                goto _error;
 204        }
 205
 206        /* create port */
 207        rc = create_port(dp);
 208        if (rc < 0) {
 209                pr_err("ALSA: seq_oss: can't create port\n");
 210                goto _error;
 211        }
 212
 213        /* allocate queue */
 214        rc = alloc_seq_queue(dp);
 215        if (rc < 0)
 216                goto _error;
 217
 218        /* set address */
 219        dp->addr.client = dp->cseq;
 220        dp->addr.port = dp->port;
 221        /*dp->addr.queue = dp->queue;*/
 222        /*dp->addr.channel = 0;*/
 223
 224        dp->seq_mode = level;
 225
 226        /* set up file mode */
 227        dp->file_mode = translate_mode(file);
 228
 229        /* initialize read queue */
 230        if (is_read_mode(dp->file_mode)) {
 231                dp->readq = snd_seq_oss_readq_new(dp, maxqlen);
 232                if (!dp->readq) {
 233                        rc = -ENOMEM;
 234                        goto _error;
 235                }
 236        }
 237
 238        /* initialize write queue */
 239        if (is_write_mode(dp->file_mode)) {
 240                dp->writeq = snd_seq_oss_writeq_new(dp, maxqlen);
 241                if (!dp->writeq) {
 242                        rc = -ENOMEM;
 243                        goto _error;
 244                }
 245        }
 246
 247        /* initialize timer */
 248        dp->timer = snd_seq_oss_timer_new(dp);
 249        if (!dp->timer) {
 250                pr_err("ALSA: seq_oss: can't alloc timer\n");
 251                rc = -ENOMEM;
 252                goto _error;
 253        }
 254
 255        /* set private data pointer */
 256        file->private_data = dp;
 257
 258        /* set up for mode2 */
 259        if (level == SNDRV_SEQ_OSS_MODE_MUSIC)
 260                snd_seq_oss_synth_setup_midi(dp);
 261        else if (is_read_mode(dp->file_mode))
 262                snd_seq_oss_midi_open_all(dp, SNDRV_SEQ_OSS_FILE_READ);
 263
 264        client_table[dp->index] = dp;
 265        num_clients++;
 266
 267        return 0;
 268
 269 _error:
 270        snd_seq_oss_synth_cleanup(dp);
 271        snd_seq_oss_midi_cleanup(dp);
 272        delete_seq_queue(dp->queue);
 273        delete_port(dp);
 274
 275        return rc;
 276}
 277
 278/*
 279 * translate file flags to private mode
 280 */
 281static int
 282translate_mode(struct file *file)
 283{
 284        int file_mode = 0;
 285        if ((file->f_flags & O_ACCMODE) != O_RDONLY)
 286                file_mode |= SNDRV_SEQ_OSS_FILE_WRITE;
 287        if ((file->f_flags & O_ACCMODE) != O_WRONLY)
 288                file_mode |= SNDRV_SEQ_OSS_FILE_READ;
 289        if (file->f_flags & O_NONBLOCK)
 290                file_mode |= SNDRV_SEQ_OSS_FILE_NONBLOCK;
 291        return file_mode;
 292}
 293
 294
 295/*
 296 * create sequencer port
 297 */
 298static int
 299create_port(struct seq_oss_devinfo *dp)
 300{
 301        int rc;
 302        struct snd_seq_port_info port;
 303        struct snd_seq_port_callback callback;
 304
 305        memset(&port, 0, sizeof(port));
 306        port.addr.client = dp->cseq;
 307        sprintf(port.name, "Sequencer-%d", dp->index);
 308        port.capability = SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_WRITE; /* no subscription */
 309        port.type = SNDRV_SEQ_PORT_TYPE_SPECIFIC;
 310        port.midi_channels = 128;
 311        port.synth_voices = 128;
 312
 313        memset(&callback, 0, sizeof(callback));
 314        callback.owner = THIS_MODULE;
 315        callback.private_data = dp;
 316        callback.event_input = snd_seq_oss_event_input;
 317        callback.private_free = free_devinfo;
 318        port.kernel = &callback;
 319
 320        rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, &port);
 321        if (rc < 0)
 322                return rc;
 323
 324        dp->port = port.addr.port;
 325
 326        return 0;
 327}
 328
 329/*
 330 * delete ALSA port
 331 */
 332static int
 333delete_port(struct seq_oss_devinfo *dp)
 334{
 335        if (dp->port < 0) {
 336                kfree(dp);
 337                return 0;
 338        }
 339
 340        return snd_seq_event_port_detach(dp->cseq, dp->port);
 341}
 342
 343/*
 344 * allocate a queue
 345 */
 346static int
 347alloc_seq_queue(struct seq_oss_devinfo *dp)
 348{
 349        struct snd_seq_queue_info qinfo;
 350        int rc;
 351
 352        memset(&qinfo, 0, sizeof(qinfo));
 353        qinfo.owner = system_client;
 354        qinfo.locked = 1;
 355        strcpy(qinfo.name, "OSS Sequencer Emulation");
 356        rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_QUEUE, &qinfo);
 357        if (rc < 0)
 358                return rc;
 359        dp->queue = qinfo.queue;
 360        return 0;
 361}
 362
 363/*
 364 * release queue
 365 */
 366static int
 367delete_seq_queue(int queue)
 368{
 369        struct snd_seq_queue_info qinfo;
 370        int rc;
 371
 372        if (queue < 0)
 373                return 0;
 374        memset(&qinfo, 0, sizeof(qinfo));
 375        qinfo.queue = queue;
 376        rc = call_ctl(SNDRV_SEQ_IOCTL_DELETE_QUEUE, &qinfo);
 377        if (rc < 0)
 378                pr_err("ALSA: seq_oss: unable to delete queue %d (%d)\n", queue, rc);
 379        return rc;
 380}
 381
 382
 383/*
 384 * free device informations - private_free callback of port
 385 */
 386static void
 387free_devinfo(void *private)
 388{
 389        struct seq_oss_devinfo *dp = (struct seq_oss_devinfo *)private;
 390
 391        snd_seq_oss_timer_delete(dp->timer);
 392                
 393        snd_seq_oss_writeq_delete(dp->writeq);
 394
 395        snd_seq_oss_readq_delete(dp->readq);
 396        
 397        kfree(dp);
 398}
 399
 400
 401/*
 402 * close sequencer device
 403 */
 404void
 405snd_seq_oss_release(struct seq_oss_devinfo *dp)
 406{
 407        int queue;
 408
 409        client_table[dp->index] = NULL;
 410        num_clients--;
 411
 412        snd_seq_oss_reset(dp);
 413
 414        snd_seq_oss_synth_cleanup(dp);
 415        snd_seq_oss_midi_cleanup(dp);
 416
 417        /* clear slot */
 418        queue = dp->queue;
 419        if (dp->port >= 0)
 420                delete_port(dp);
 421        delete_seq_queue(queue);
 422}
 423
 424
 425/*
 426 * reset sequencer devices
 427 */
 428void
 429snd_seq_oss_reset(struct seq_oss_devinfo *dp)
 430{
 431        int i;
 432
 433        /* reset all synth devices */
 434        for (i = 0; i < dp->max_synthdev; i++)
 435                snd_seq_oss_synth_reset(dp, i);
 436
 437        /* reset all midi devices */
 438        if (dp->seq_mode != SNDRV_SEQ_OSS_MODE_MUSIC) {
 439                for (i = 0; i < dp->max_mididev; i++)
 440                        snd_seq_oss_midi_reset(dp, i);
 441        }
 442
 443        /* remove queues */
 444        if (dp->readq)
 445                snd_seq_oss_readq_clear(dp->readq);
 446        if (dp->writeq)
 447                snd_seq_oss_writeq_clear(dp->writeq);
 448
 449        /* reset timer */
 450        snd_seq_oss_timer_stop(dp->timer);
 451}
 452
 453#ifdef CONFIG_SND_PROC_FS
 454/*
 455 * misc. functions for proc interface
 456 */
 457char *
 458enabled_str(int bool)
 459{
 460        return bool ? "enabled" : "disabled";
 461}
 462
 463static const char *
 464filemode_str(int val)
 465{
 466        static const char * const str[] = {
 467                "none", "read", "write", "read/write",
 468        };
 469        return str[val & SNDRV_SEQ_OSS_FILE_ACMODE];
 470}
 471
 472
 473/*
 474 * proc interface
 475 */
 476void
 477snd_seq_oss_system_info_read(struct snd_info_buffer *buf)
 478{
 479        int i;
 480        struct seq_oss_devinfo *dp;
 481
 482        snd_iprintf(buf, "ALSA client number %d\n", system_client);
 483        snd_iprintf(buf, "ALSA receiver port %d\n", system_port);
 484
 485        snd_iprintf(buf, "\nNumber of applications: %d\n", num_clients);
 486        for (i = 0; i < num_clients; i++) {
 487                snd_iprintf(buf, "\nApplication %d: ", i);
 488                dp = client_table[i];
 489                if (!dp) {
 490                        snd_iprintf(buf, "*empty*\n");
 491                        continue;
 492                }
 493                snd_iprintf(buf, "port %d : queue %d\n", dp->port, dp->queue);
 494                snd_iprintf(buf, "  sequencer mode = %s : file open mode = %s\n",
 495                            (dp->seq_mode ? "music" : "synth"),
 496                            filemode_str(dp->file_mode));
 497                if (dp->seq_mode)
 498                        snd_iprintf(buf, "  timer tempo = %d, timebase = %d\n",
 499                                    dp->timer->oss_tempo, dp->timer->oss_timebase);
 500                snd_iprintf(buf, "  max queue length %d\n", maxqlen);
 501                if (is_read_mode(dp->file_mode) && dp->readq)
 502                        snd_seq_oss_readq_info_read(dp->readq, buf);
 503        }
 504}
 505#endif /* CONFIG_SND_PROC_FS */
 506