Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * ALSA sequencer Ports |
| 3 | * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl> |
| 4 | * Jaroslav Kysela <perex@suse.cz> |
| 5 | * |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <sound/driver.h> |
| 24 | #include <sound/core.h> |
| 25 | #include <linux/slab.h> |
| 26 | #include "seq_system.h" |
| 27 | #include "seq_ports.h" |
| 28 | #include "seq_clientmgr.h" |
| 29 | |
| 30 | /* |
| 31 | |
| 32 | registration of client ports |
| 33 | |
| 34 | */ |
| 35 | |
| 36 | |
| 37 | /* |
| 38 | |
| 39 | NOTE: the current implementation of the port structure as a linked list is |
| 40 | not optimal for clients that have many ports. For sending messages to all |
| 41 | subscribers of a port we first need to find the address of the port |
| 42 | structure, which means we have to traverse the list. A direct access table |
| 43 | (array) would be better, but big preallocated arrays waste memory. |
| 44 | |
| 45 | Possible actions: |
| 46 | |
| 47 | 1) leave it this way, a client does normaly does not have more than a few |
| 48 | ports |
| 49 | |
| 50 | 2) replace the linked list of ports by a array of pointers which is |
| 51 | dynamicly kmalloced. When a port is added or deleted we can simply allocate |
| 52 | a new array, copy the corresponding pointers, and delete the old one. We |
| 53 | then only need a pointer to this array, and an integer that tells us how |
| 54 | much elements are in array. |
| 55 | |
| 56 | */ |
| 57 | |
| 58 | /* return pointer to port structure - port is locked if found */ |
| 59 | client_port_t *snd_seq_port_use_ptr(client_t *client, int num) |
| 60 | { |
| 61 | struct list_head *p; |
| 62 | client_port_t *port; |
| 63 | |
| 64 | if (client == NULL) |
| 65 | return NULL; |
| 66 | read_lock(&client->ports_lock); |
| 67 | list_for_each(p, &client->ports_list_head) { |
| 68 | port = list_entry(p, client_port_t, list); |
| 69 | if (port->addr.port == num) { |
| 70 | if (port->closing) |
| 71 | break; /* deleting now */ |
| 72 | snd_use_lock_use(&port->use_lock); |
| 73 | read_unlock(&client->ports_lock); |
| 74 | return port; |
| 75 | } |
| 76 | } |
| 77 | read_unlock(&client->ports_lock); |
| 78 | return NULL; /* not found */ |
| 79 | } |
| 80 | |
| 81 | |
| 82 | /* search for the next port - port is locked if found */ |
| 83 | client_port_t *snd_seq_port_query_nearest(client_t *client, snd_seq_port_info_t *pinfo) |
| 84 | { |
| 85 | int num; |
| 86 | struct list_head *p; |
| 87 | client_port_t *port, *found; |
| 88 | |
| 89 | num = pinfo->addr.port; |
| 90 | found = NULL; |
| 91 | read_lock(&client->ports_lock); |
| 92 | list_for_each(p, &client->ports_list_head) { |
| 93 | port = list_entry(p, client_port_t, list); |
| 94 | if (port->addr.port < num) |
| 95 | continue; |
| 96 | if (port->addr.port == num) { |
| 97 | found = port; |
| 98 | break; |
| 99 | } |
| 100 | if (found == NULL || port->addr.port < found->addr.port) |
| 101 | found = port; |
| 102 | } |
| 103 | if (found) { |
| 104 | if (found->closing) |
| 105 | found = NULL; |
| 106 | else |
| 107 | snd_use_lock_use(&found->use_lock); |
| 108 | } |
| 109 | read_unlock(&client->ports_lock); |
| 110 | return found; |
| 111 | } |
| 112 | |
| 113 | |
| 114 | /* initialize port_subs_info_t */ |
| 115 | static void port_subs_info_init(port_subs_info_t *grp) |
| 116 | { |
| 117 | INIT_LIST_HEAD(&grp->list_head); |
| 118 | grp->count = 0; |
| 119 | grp->exclusive = 0; |
| 120 | rwlock_init(&grp->list_lock); |
| 121 | init_rwsem(&grp->list_mutex); |
| 122 | grp->open = NULL; |
| 123 | grp->close = NULL; |
| 124 | } |
| 125 | |
| 126 | |
| 127 | /* create a port, port number is returned (-1 on failure) */ |
| 128 | client_port_t *snd_seq_create_port(client_t *client, int port) |
| 129 | { |
| 130 | unsigned long flags; |
| 131 | client_port_t *new_port; |
| 132 | struct list_head *l; |
| 133 | int num = -1; |
| 134 | |
| 135 | /* sanity check */ |
| 136 | snd_assert(client, return NULL); |
| 137 | |
| 138 | if (client->num_ports >= SNDRV_SEQ_MAX_PORTS - 1) { |
| 139 | snd_printk(KERN_WARNING "too many ports for client %d\n", client->number); |
| 140 | return NULL; |
| 141 | } |
| 142 | |
| 143 | /* create a new port */ |
Takashi Iwai | ecca82b | 2005-09-09 14:20:49 +0200 | [diff] [blame^] | 144 | new_port = kzalloc(sizeof(*new_port), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | if (! new_port) { |
| 146 | snd_printd("malloc failed for registering client port\n"); |
| 147 | return NULL; /* failure, out of memory */ |
| 148 | } |
| 149 | /* init port data */ |
| 150 | new_port->addr.client = client->number; |
| 151 | new_port->addr.port = -1; |
| 152 | new_port->owner = THIS_MODULE; |
| 153 | sprintf(new_port->name, "port-%d", num); |
| 154 | snd_use_lock_init(&new_port->use_lock); |
| 155 | port_subs_info_init(&new_port->c_src); |
| 156 | port_subs_info_init(&new_port->c_dest); |
| 157 | |
| 158 | num = port >= 0 ? port : 0; |
| 159 | down(&client->ports_mutex); |
| 160 | write_lock_irqsave(&client->ports_lock, flags); |
| 161 | list_for_each(l, &client->ports_list_head) { |
| 162 | client_port_t *p = list_entry(l, client_port_t, list); |
| 163 | if (p->addr.port > num) |
| 164 | break; |
| 165 | if (port < 0) /* auto-probe mode */ |
| 166 | num = p->addr.port + 1; |
| 167 | } |
| 168 | /* insert the new port */ |
| 169 | list_add_tail(&new_port->list, l); |
| 170 | client->num_ports++; |
| 171 | new_port->addr.port = num; /* store the port number in the port */ |
| 172 | write_unlock_irqrestore(&client->ports_lock, flags); |
| 173 | up(&client->ports_mutex); |
| 174 | sprintf(new_port->name, "port-%d", num); |
| 175 | |
| 176 | return new_port; |
| 177 | } |
| 178 | |
| 179 | /* */ |
| 180 | enum group_type_t { |
| 181 | SRC_LIST, DEST_LIST |
| 182 | }; |
| 183 | |
| 184 | static int subscribe_port(client_t *client, client_port_t *port, port_subs_info_t *grp, snd_seq_port_subscribe_t *info, int send_ack); |
| 185 | static int unsubscribe_port(client_t *client, client_port_t *port, port_subs_info_t *grp, snd_seq_port_subscribe_t *info, int send_ack); |
| 186 | |
| 187 | |
| 188 | static client_port_t *get_client_port(snd_seq_addr_t *addr, client_t **cp) |
| 189 | { |
| 190 | client_port_t *p; |
| 191 | *cp = snd_seq_client_use_ptr(addr->client); |
| 192 | if (*cp) { |
| 193 | p = snd_seq_port_use_ptr(*cp, addr->port); |
| 194 | if (! p) { |
| 195 | snd_seq_client_unlock(*cp); |
| 196 | *cp = NULL; |
| 197 | } |
| 198 | return p; |
| 199 | } |
| 200 | return NULL; |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * remove all subscribers on the list |
| 205 | * this is called from port_delete, for each src and dest list. |
| 206 | */ |
| 207 | static void clear_subscriber_list(client_t *client, client_port_t *port, |
| 208 | port_subs_info_t *grp, int grptype) |
| 209 | { |
| 210 | struct list_head *p, *n; |
| 211 | |
| 212 | down_write(&grp->list_mutex); |
| 213 | list_for_each_safe(p, n, &grp->list_head) { |
| 214 | subscribers_t *subs; |
| 215 | client_t *c; |
| 216 | client_port_t *aport; |
| 217 | |
| 218 | if (grptype == SRC_LIST) { |
| 219 | subs = list_entry(p, subscribers_t, src_list); |
| 220 | aport = get_client_port(&subs->info.dest, &c); |
| 221 | } else { |
| 222 | subs = list_entry(p, subscribers_t, dest_list); |
| 223 | aport = get_client_port(&subs->info.sender, &c); |
| 224 | } |
| 225 | list_del(p); |
| 226 | unsubscribe_port(client, port, grp, &subs->info, 0); |
| 227 | if (!aport) { |
| 228 | /* looks like the connected port is being deleted. |
| 229 | * we decrease the counter, and when both ports are deleted |
| 230 | * remove the subscriber info |
| 231 | */ |
| 232 | if (atomic_dec_and_test(&subs->ref_count)) |
| 233 | kfree(subs); |
| 234 | } else { |
| 235 | /* ok we got the connected port */ |
| 236 | port_subs_info_t *agrp; |
| 237 | agrp = (grptype == SRC_LIST) ? &aport->c_dest : &aport->c_src; |
| 238 | down_write(&agrp->list_mutex); |
| 239 | if (grptype == SRC_LIST) |
| 240 | list_del(&subs->dest_list); |
| 241 | else |
| 242 | list_del(&subs->src_list); |
| 243 | unsubscribe_port(c, aport, agrp, &subs->info, 1); |
| 244 | kfree(subs); |
| 245 | up_write(&agrp->list_mutex); |
| 246 | snd_seq_port_unlock(aport); |
| 247 | snd_seq_client_unlock(c); |
| 248 | } |
| 249 | } |
| 250 | up_write(&grp->list_mutex); |
| 251 | } |
| 252 | |
| 253 | /* delete port data */ |
| 254 | static int port_delete(client_t *client, client_port_t *port) |
| 255 | { |
| 256 | /* set closing flag and wait for all port access are gone */ |
| 257 | port->closing = 1; |
| 258 | snd_use_lock_sync(&port->use_lock); |
| 259 | |
| 260 | /* clear subscribers info */ |
| 261 | clear_subscriber_list(client, port, &port->c_src, SRC_LIST); |
| 262 | clear_subscriber_list(client, port, &port->c_dest, DEST_LIST); |
| 263 | |
| 264 | if (port->private_free) |
| 265 | port->private_free(port->private_data); |
| 266 | |
| 267 | snd_assert(port->c_src.count == 0,); |
| 268 | snd_assert(port->c_dest.count == 0,); |
| 269 | |
| 270 | kfree(port); |
| 271 | return 0; |
| 272 | } |
| 273 | |
| 274 | |
| 275 | /* delete a port with the given port id */ |
| 276 | int snd_seq_delete_port(client_t *client, int port) |
| 277 | { |
| 278 | unsigned long flags; |
| 279 | struct list_head *l; |
| 280 | client_port_t *found = NULL; |
| 281 | |
| 282 | down(&client->ports_mutex); |
| 283 | write_lock_irqsave(&client->ports_lock, flags); |
| 284 | list_for_each(l, &client->ports_list_head) { |
| 285 | client_port_t *p = list_entry(l, client_port_t, list); |
| 286 | if (p->addr.port == port) { |
| 287 | /* ok found. delete from the list at first */ |
| 288 | list_del(l); |
| 289 | client->num_ports--; |
| 290 | found = p; |
| 291 | break; |
| 292 | } |
| 293 | } |
| 294 | write_unlock_irqrestore(&client->ports_lock, flags); |
| 295 | up(&client->ports_mutex); |
| 296 | if (found) |
| 297 | return port_delete(client, found); |
| 298 | else |
| 299 | return -ENOENT; |
| 300 | } |
| 301 | |
| 302 | /* delete the all ports belonging to the given client */ |
| 303 | int snd_seq_delete_all_ports(client_t *client) |
| 304 | { |
| 305 | unsigned long flags; |
| 306 | struct list_head deleted_list, *p, *n; |
| 307 | |
| 308 | /* move the port list to deleted_list, and |
| 309 | * clear the port list in the client data. |
| 310 | */ |
| 311 | down(&client->ports_mutex); |
| 312 | write_lock_irqsave(&client->ports_lock, flags); |
| 313 | if (! list_empty(&client->ports_list_head)) { |
| 314 | __list_add(&deleted_list, |
| 315 | client->ports_list_head.prev, |
| 316 | client->ports_list_head.next); |
| 317 | INIT_LIST_HEAD(&client->ports_list_head); |
| 318 | } else { |
| 319 | INIT_LIST_HEAD(&deleted_list); |
| 320 | } |
| 321 | client->num_ports = 0; |
| 322 | write_unlock_irqrestore(&client->ports_lock, flags); |
| 323 | |
| 324 | /* remove each port in deleted_list */ |
| 325 | list_for_each_safe(p, n, &deleted_list) { |
| 326 | client_port_t *port = list_entry(p, client_port_t, list); |
| 327 | list_del(p); |
| 328 | snd_seq_system_client_ev_port_exit(port->addr.client, port->addr.port); |
| 329 | port_delete(client, port); |
| 330 | } |
| 331 | up(&client->ports_mutex); |
| 332 | return 0; |
| 333 | } |
| 334 | |
| 335 | /* set port info fields */ |
| 336 | int snd_seq_set_port_info(client_port_t * port, snd_seq_port_info_t * info) |
| 337 | { |
| 338 | snd_assert(port && info, return -EINVAL); |
| 339 | |
| 340 | /* set port name */ |
| 341 | if (info->name[0]) |
| 342 | strlcpy(port->name, info->name, sizeof(port->name)); |
| 343 | |
| 344 | /* set capabilities */ |
| 345 | port->capability = info->capability; |
| 346 | |
| 347 | /* get port type */ |
| 348 | port->type = info->type; |
| 349 | |
| 350 | /* information about supported channels/voices */ |
| 351 | port->midi_channels = info->midi_channels; |
| 352 | port->midi_voices = info->midi_voices; |
| 353 | port->synth_voices = info->synth_voices; |
| 354 | |
| 355 | /* timestamping */ |
| 356 | port->timestamping = (info->flags & SNDRV_SEQ_PORT_FLG_TIMESTAMP) ? 1 : 0; |
| 357 | port->time_real = (info->flags & SNDRV_SEQ_PORT_FLG_TIME_REAL) ? 1 : 0; |
| 358 | port->time_queue = info->time_queue; |
| 359 | |
| 360 | return 0; |
| 361 | } |
| 362 | |
| 363 | /* get port info fields */ |
| 364 | int snd_seq_get_port_info(client_port_t * port, snd_seq_port_info_t * info) |
| 365 | { |
| 366 | snd_assert(port && info, return -EINVAL); |
| 367 | |
| 368 | /* get port name */ |
| 369 | strlcpy(info->name, port->name, sizeof(info->name)); |
| 370 | |
| 371 | /* get capabilities */ |
| 372 | info->capability = port->capability; |
| 373 | |
| 374 | /* get port type */ |
| 375 | info->type = port->type; |
| 376 | |
| 377 | /* information about supported channels/voices */ |
| 378 | info->midi_channels = port->midi_channels; |
| 379 | info->midi_voices = port->midi_voices; |
| 380 | info->synth_voices = port->synth_voices; |
| 381 | |
| 382 | /* get subscriber counts */ |
| 383 | info->read_use = port->c_src.count; |
| 384 | info->write_use = port->c_dest.count; |
| 385 | |
| 386 | /* timestamping */ |
| 387 | info->flags = 0; |
| 388 | if (port->timestamping) { |
| 389 | info->flags |= SNDRV_SEQ_PORT_FLG_TIMESTAMP; |
| 390 | if (port->time_real) |
| 391 | info->flags |= SNDRV_SEQ_PORT_FLG_TIME_REAL; |
| 392 | info->time_queue = port->time_queue; |
| 393 | } |
| 394 | |
| 395 | return 0; |
| 396 | } |
| 397 | |
| 398 | |
| 399 | |
| 400 | /* |
| 401 | * call callback functions (if any): |
| 402 | * the callbacks are invoked only when the first (for connection) or |
| 403 | * the last subscription (for disconnection) is done. Second or later |
| 404 | * subscription results in increment of counter, but no callback is |
| 405 | * invoked. |
| 406 | * This feature is useful if these callbacks are associated with |
| 407 | * initialization or termination of devices (see seq_midi.c). |
| 408 | * |
| 409 | * If callback_all option is set, the callback function is invoked |
| 410 | * at each connnection/disconnection. |
| 411 | */ |
| 412 | |
| 413 | static int subscribe_port(client_t *client, client_port_t *port, port_subs_info_t *grp, |
| 414 | snd_seq_port_subscribe_t *info, int send_ack) |
| 415 | { |
| 416 | int err = 0; |
| 417 | |
| 418 | if (!try_module_get(port->owner)) |
| 419 | return -EFAULT; |
| 420 | grp->count++; |
| 421 | if (grp->open && (port->callback_all || grp->count == 1)) { |
| 422 | err = grp->open(port->private_data, info); |
| 423 | if (err < 0) { |
| 424 | module_put(port->owner); |
| 425 | grp->count--; |
| 426 | } |
| 427 | } |
| 428 | if (err >= 0 && send_ack && client->type == USER_CLIENT) |
| 429 | snd_seq_client_notify_subscription(port->addr.client, port->addr.port, |
| 430 | info, SNDRV_SEQ_EVENT_PORT_SUBSCRIBED); |
| 431 | |
| 432 | return err; |
| 433 | } |
| 434 | |
| 435 | static int unsubscribe_port(client_t *client, client_port_t *port, |
| 436 | port_subs_info_t *grp, |
| 437 | snd_seq_port_subscribe_t *info, int send_ack) |
| 438 | { |
| 439 | int err = 0; |
| 440 | |
| 441 | if (! grp->count) |
| 442 | return -EINVAL; |
| 443 | grp->count--; |
| 444 | if (grp->close && (port->callback_all || grp->count == 0)) |
| 445 | err = grp->close(port->private_data, info); |
| 446 | if (send_ack && client->type == USER_CLIENT) |
| 447 | snd_seq_client_notify_subscription(port->addr.client, port->addr.port, |
| 448 | info, SNDRV_SEQ_EVENT_PORT_UNSUBSCRIBED); |
| 449 | module_put(port->owner); |
| 450 | return err; |
| 451 | } |
| 452 | |
| 453 | |
| 454 | |
| 455 | /* check if both addresses are identical */ |
| 456 | static inline int addr_match(snd_seq_addr_t *r, snd_seq_addr_t *s) |
| 457 | { |
| 458 | return (r->client == s->client) && (r->port == s->port); |
| 459 | } |
| 460 | |
| 461 | /* check the two subscribe info match */ |
| 462 | /* if flags is zero, checks only sender and destination addresses */ |
| 463 | static int match_subs_info(snd_seq_port_subscribe_t *r, |
| 464 | snd_seq_port_subscribe_t *s) |
| 465 | { |
| 466 | if (addr_match(&r->sender, &s->sender) && |
| 467 | addr_match(&r->dest, &s->dest)) { |
| 468 | if (r->flags && r->flags == s->flags) |
| 469 | return r->queue == s->queue; |
| 470 | else if (! r->flags) |
| 471 | return 1; |
| 472 | } |
| 473 | return 0; |
| 474 | } |
| 475 | |
| 476 | |
| 477 | /* connect two ports */ |
| 478 | int snd_seq_port_connect(client_t *connector, |
| 479 | client_t *src_client, client_port_t *src_port, |
| 480 | client_t *dest_client, client_port_t *dest_port, |
| 481 | snd_seq_port_subscribe_t *info) |
| 482 | { |
| 483 | port_subs_info_t *src = &src_port->c_src; |
| 484 | port_subs_info_t *dest = &dest_port->c_dest; |
| 485 | subscribers_t *subs; |
| 486 | struct list_head *p; |
| 487 | int err, src_called = 0; |
| 488 | unsigned long flags; |
| 489 | int exclusive; |
| 490 | |
Takashi Iwai | ecca82b | 2005-09-09 14:20:49 +0200 | [diff] [blame^] | 491 | subs = kzalloc(sizeof(*subs), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 492 | if (! subs) |
| 493 | return -ENOMEM; |
| 494 | |
| 495 | subs->info = *info; |
| 496 | atomic_set(&subs->ref_count, 2); |
| 497 | |
| 498 | down_write(&src->list_mutex); |
| 499 | down_write(&dest->list_mutex); |
| 500 | |
| 501 | exclusive = info->flags & SNDRV_SEQ_PORT_SUBS_EXCLUSIVE ? 1 : 0; |
| 502 | err = -EBUSY; |
| 503 | if (exclusive) { |
| 504 | if (! list_empty(&src->list_head) || ! list_empty(&dest->list_head)) |
| 505 | goto __error; |
| 506 | } else { |
| 507 | if (src->exclusive || dest->exclusive) |
| 508 | goto __error; |
| 509 | /* check whether already exists */ |
| 510 | list_for_each(p, &src->list_head) { |
| 511 | subscribers_t *s = list_entry(p, subscribers_t, src_list); |
| 512 | if (match_subs_info(info, &s->info)) |
| 513 | goto __error; |
| 514 | } |
| 515 | list_for_each(p, &dest->list_head) { |
| 516 | subscribers_t *s = list_entry(p, subscribers_t, dest_list); |
| 517 | if (match_subs_info(info, &s->info)) |
| 518 | goto __error; |
| 519 | } |
| 520 | } |
| 521 | |
| 522 | if ((err = subscribe_port(src_client, src_port, src, info, |
| 523 | connector->number != src_client->number)) < 0) |
| 524 | goto __error; |
| 525 | src_called = 1; |
| 526 | |
| 527 | if ((err = subscribe_port(dest_client, dest_port, dest, info, |
| 528 | connector->number != dest_client->number)) < 0) |
| 529 | goto __error; |
| 530 | |
| 531 | /* add to list */ |
| 532 | write_lock_irqsave(&src->list_lock, flags); |
| 533 | // write_lock(&dest->list_lock); // no other lock yet |
| 534 | list_add_tail(&subs->src_list, &src->list_head); |
| 535 | list_add_tail(&subs->dest_list, &dest->list_head); |
| 536 | // write_unlock(&dest->list_lock); // no other lock yet |
| 537 | write_unlock_irqrestore(&src->list_lock, flags); |
| 538 | |
| 539 | src->exclusive = dest->exclusive = exclusive; |
| 540 | |
| 541 | up_write(&dest->list_mutex); |
| 542 | up_write(&src->list_mutex); |
| 543 | return 0; |
| 544 | |
| 545 | __error: |
| 546 | if (src_called) |
| 547 | unsubscribe_port(src_client, src_port, src, info, |
| 548 | connector->number != src_client->number); |
| 549 | kfree(subs); |
| 550 | up_write(&dest->list_mutex); |
| 551 | up_write(&src->list_mutex); |
| 552 | return err; |
| 553 | } |
| 554 | |
| 555 | |
| 556 | /* remove the connection */ |
| 557 | int snd_seq_port_disconnect(client_t *connector, |
| 558 | client_t *src_client, client_port_t *src_port, |
| 559 | client_t *dest_client, client_port_t *dest_port, |
| 560 | snd_seq_port_subscribe_t *info) |
| 561 | { |
| 562 | port_subs_info_t *src = &src_port->c_src; |
| 563 | port_subs_info_t *dest = &dest_port->c_dest; |
| 564 | subscribers_t *subs; |
| 565 | struct list_head *p; |
| 566 | int err = -ENOENT; |
| 567 | unsigned long flags; |
| 568 | |
| 569 | down_write(&src->list_mutex); |
| 570 | down_write(&dest->list_mutex); |
| 571 | |
| 572 | /* look for the connection */ |
| 573 | list_for_each(p, &src->list_head) { |
| 574 | subs = list_entry(p, subscribers_t, src_list); |
| 575 | if (match_subs_info(info, &subs->info)) { |
| 576 | write_lock_irqsave(&src->list_lock, flags); |
| 577 | // write_lock(&dest->list_lock); // no lock yet |
| 578 | list_del(&subs->src_list); |
| 579 | list_del(&subs->dest_list); |
| 580 | // write_unlock(&dest->list_lock); |
| 581 | write_unlock_irqrestore(&src->list_lock, flags); |
| 582 | src->exclusive = dest->exclusive = 0; |
| 583 | unsubscribe_port(src_client, src_port, src, info, |
| 584 | connector->number != src_client->number); |
| 585 | unsubscribe_port(dest_client, dest_port, dest, info, |
| 586 | connector->number != dest_client->number); |
| 587 | kfree(subs); |
| 588 | err = 0; |
| 589 | break; |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | up_write(&dest->list_mutex); |
| 594 | up_write(&src->list_mutex); |
| 595 | return err; |
| 596 | } |
| 597 | |
| 598 | |
| 599 | /* get matched subscriber */ |
| 600 | subscribers_t *snd_seq_port_get_subscription(port_subs_info_t *src_grp, |
| 601 | snd_seq_addr_t *dest_addr) |
| 602 | { |
| 603 | struct list_head *p; |
| 604 | subscribers_t *s, *found = NULL; |
| 605 | |
| 606 | down_read(&src_grp->list_mutex); |
| 607 | list_for_each(p, &src_grp->list_head) { |
| 608 | s = list_entry(p, subscribers_t, src_list); |
| 609 | if (addr_match(dest_addr, &s->info.dest)) { |
| 610 | found = s; |
| 611 | break; |
| 612 | } |
| 613 | } |
| 614 | up_read(&src_grp->list_mutex); |
| 615 | return found; |
| 616 | } |
| 617 | |
| 618 | /* |
| 619 | * Attach a device driver that wants to receive events from the |
| 620 | * sequencer. Returns the new port number on success. |
| 621 | * A driver that wants to receive the events converted to midi, will |
| 622 | * use snd_seq_midisynth_register_port(). |
| 623 | */ |
| 624 | /* exported */ |
| 625 | int snd_seq_event_port_attach(int client, |
| 626 | snd_seq_port_callback_t *pcbp, |
| 627 | int cap, int type, int midi_channels, |
| 628 | int midi_voices, char *portname) |
| 629 | { |
| 630 | snd_seq_port_info_t portinfo; |
| 631 | int ret; |
| 632 | |
| 633 | /* Set up the port */ |
| 634 | memset(&portinfo, 0, sizeof(portinfo)); |
| 635 | portinfo.addr.client = client; |
| 636 | strlcpy(portinfo.name, portname ? portname : "Unamed port", |
| 637 | sizeof(portinfo.name)); |
| 638 | |
| 639 | portinfo.capability = cap; |
| 640 | portinfo.type = type; |
| 641 | portinfo.kernel = pcbp; |
| 642 | portinfo.midi_channels = midi_channels; |
| 643 | portinfo.midi_voices = midi_voices; |
| 644 | |
| 645 | /* Create it */ |
| 646 | ret = snd_seq_kernel_client_ctl(client, |
| 647 | SNDRV_SEQ_IOCTL_CREATE_PORT, |
| 648 | &portinfo); |
| 649 | |
| 650 | if (ret >= 0) |
| 651 | ret = portinfo.addr.port; |
| 652 | |
| 653 | return ret; |
| 654 | } |
| 655 | |
| 656 | |
| 657 | /* |
| 658 | * Detach the driver from a port. |
| 659 | */ |
| 660 | /* exported */ |
| 661 | int snd_seq_event_port_detach(int client, int port) |
| 662 | { |
| 663 | snd_seq_port_info_t portinfo; |
| 664 | int err; |
| 665 | |
| 666 | memset(&portinfo, 0, sizeof(portinfo)); |
| 667 | portinfo.addr.client = client; |
| 668 | portinfo.addr.port = port; |
| 669 | err = snd_seq_kernel_client_ctl(client, |
| 670 | SNDRV_SEQ_IOCTL_DELETE_PORT, |
| 671 | &portinfo); |
| 672 | |
| 673 | return err; |
| 674 | } |