linux/sound/core/init.c
<<
>>
Prefs
   1/*
   2 *  Initialization routines
   3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   4 *
   5 *
   6 *   This program is free software; you can redistribute it and/or modify
   7 *   it under the terms of the GNU General Public License as published by
   8 *   the Free Software Foundation; either version 2 of the License, or
   9 *   (at your option) any later version.
  10 *
  11 *   This program is distributed in the hope that it will be useful,
  12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *   GNU General Public License for more details.
  15 *
  16 *   You should have received a copy of the GNU General Public License
  17 *   along with this program; if not, write to the Free Software
  18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19 *
  20 */
  21
  22#include <linux/init.h>
  23#include <linux/sched.h>
  24#include <linux/module.h>
  25#include <linux/device.h>
  26#include <linux/file.h>
  27#include <linux/slab.h>
  28#include <linux/time.h>
  29#include <linux/ctype.h>
  30#include <linux/pm.h>
  31
  32#include <sound/core.h>
  33#include <sound/control.h>
  34#include <sound/info.h>
  35
  36/* monitor files for graceful shutdown (hotplug) */
  37struct snd_monitor_file {
  38        struct file *file;
  39        const struct file_operations *disconnected_f_op;
  40        struct list_head shutdown_list; /* still need to shutdown */
  41        struct list_head list;  /* link of monitor files */
  42};
  43
  44static DEFINE_SPINLOCK(shutdown_lock);
  45static LIST_HEAD(shutdown_files);
  46
  47static const struct file_operations snd_shutdown_f_ops;
  48
  49static unsigned int snd_cards_lock;     /* locked for registering/using */
  50struct snd_card *snd_cards[SNDRV_CARDS];
  51EXPORT_SYMBOL(snd_cards);
  52
  53static DEFINE_MUTEX(snd_card_mutex);
  54
  55static char *slots[SNDRV_CARDS];
  56module_param_array(slots, charp, NULL, 0444);
  57MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
  58
  59/* return non-zero if the given index is reserved for the given
  60 * module via slots option
  61 */
  62static int module_slot_match(struct module *module, int idx)
  63{
  64        int match = 1;
  65#ifdef MODULE
  66        const char *s1, *s2;
  67
  68        if (!module || !module->name || !slots[idx])
  69                return 0;
  70
  71        s1 = module->name;
  72        s2 = slots[idx];
  73        if (*s2 == '!') {
  74                match = 0; /* negative match */
  75                s2++;
  76        }
  77        /* compare module name strings
  78         * hyphens are handled as equivalent with underscore
  79         */
  80        for (;;) {
  81                char c1 = *s1++;
  82                char c2 = *s2++;
  83                if (c1 == '-')
  84                        c1 = '_';
  85                if (c2 == '-')
  86                        c2 = '_';
  87                if (c1 != c2)
  88                        return !match;
  89                if (!c1)
  90                        break;
  91        }
  92#endif /* MODULE */
  93        return match;
  94}
  95
  96#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
  97int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
  98EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
  99#endif
 100
 101#ifdef CONFIG_PROC_FS
 102static void snd_card_id_read(struct snd_info_entry *entry,
 103                             struct snd_info_buffer *buffer)
 104{
 105        snd_iprintf(buffer, "%s\n", entry->card->id);
 106}
 107
 108static inline int init_info_for_card(struct snd_card *card)
 109{
 110        int err;
 111        struct snd_info_entry *entry;
 112
 113        if ((err = snd_info_card_register(card)) < 0) {
 114                snd_printd("unable to create card info\n");
 115                return err;
 116        }
 117        if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
 118                snd_printd("unable to create card entry\n");
 119                return err;
 120        }
 121        entry->c.text.read = snd_card_id_read;
 122        if (snd_info_register(entry) < 0) {
 123                snd_info_free_entry(entry);
 124                entry = NULL;
 125        }
 126        card->proc_id = entry;
 127        return 0;
 128}
 129#else /* !CONFIG_PROC_FS */
 130#define init_info_for_card(card)
 131#endif
 132
 133/**
 134 *  snd_card_create - create and initialize a soundcard structure
 135 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
 136 *  @xid: card identification (ASCII string)
 137 *  @module: top level module for locking
 138 *  @extra_size: allocate this extra size after the main soundcard structure
 139 *  @card_ret: the pointer to store the created card instance
 140 *
 141 *  Creates and initializes a soundcard structure.
 142 *
 143 *  The function allocates snd_card instance via kzalloc with the given
 144 *  space for the driver to use freely.  The allocated struct is stored
 145 *  in the given card_ret pointer.
 146 *
 147 *  Returns zero if successful or a negative error code.
 148 */
 149int snd_card_create(int idx, const char *xid,
 150                    struct module *module, int extra_size,
 151                    struct snd_card **card_ret)
 152{
 153        struct snd_card *card;
 154        int err, idx2;
 155
 156        if (snd_BUG_ON(!card_ret))
 157                return -EINVAL;
 158        *card_ret = NULL;
 159
 160        if (extra_size < 0)
 161                extra_size = 0;
 162        card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
 163        if (!card)
 164                return -ENOMEM;
 165        if (xid)
 166                strlcpy(card->id, xid, sizeof(card->id));
 167        err = 0;
 168        mutex_lock(&snd_card_mutex);
 169        if (idx < 0) {
 170                for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
 171                        /* idx == -1 == 0xffff means: take any free slot */
 172                        if (~snd_cards_lock & idx & 1<<idx2) {
 173                                if (module_slot_match(module, idx2)) {
 174                                        idx = idx2;
 175                                        break;
 176                                }
 177                        }
 178        }
 179        if (idx < 0) {
 180                for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
 181                        /* idx == -1 == 0xffff means: take any free slot */
 182                        if (~snd_cards_lock & idx & 1<<idx2) {
 183                                if (!slots[idx2] || !*slots[idx2]) {
 184                                        idx = idx2;
 185                                        break;
 186                                }
 187                        }
 188        }
 189        if (idx < 0)
 190                err = -ENODEV;
 191        else if (idx < snd_ecards_limit) {
 192                if (snd_cards_lock & (1 << idx))
 193                        err = -EBUSY;   /* invalid */
 194        } else if (idx >= SNDRV_CARDS)
 195                err = -ENODEV;
 196        if (err < 0) {
 197                mutex_unlock(&snd_card_mutex);
 198                snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
 199                         idx, snd_ecards_limit - 1, err);
 200                goto __error;
 201        }
 202        snd_cards_lock |= 1 << idx;             /* lock it */
 203        if (idx >= snd_ecards_limit)
 204                snd_ecards_limit = idx + 1; /* increase the limit */
 205        mutex_unlock(&snd_card_mutex);
 206        card->number = idx;
 207        card->module = module;
 208        INIT_LIST_HEAD(&card->devices);
 209        init_rwsem(&card->controls_rwsem);
 210        rwlock_init(&card->ctl_files_rwlock);
 211        INIT_LIST_HEAD(&card->controls);
 212        INIT_LIST_HEAD(&card->ctl_files);
 213        spin_lock_init(&card->files_lock);
 214        INIT_LIST_HEAD(&card->files_list);
 215        init_waitqueue_head(&card->shutdown_sleep);
 216        atomic_set(&card->refcount, 0);
 217#ifdef CONFIG_PM
 218        mutex_init(&card->power_lock);
 219        init_waitqueue_head(&card->power_sleep);
 220#endif
 221        /* the control interface cannot be accessed from the user space until */
 222        /* snd_cards_bitmask and snd_cards are set with snd_card_register */
 223        err = snd_ctl_create(card);
 224        if (err < 0) {
 225                snd_printk(KERN_ERR "unable to register control minors\n");
 226                goto __error;
 227        }
 228        err = snd_info_card_create(card);
 229        if (err < 0) {
 230                snd_printk(KERN_ERR "unable to create card info\n");
 231                goto __error_ctl;
 232        }
 233        if (extra_size > 0)
 234                card->private_data = (char *)card + sizeof(struct snd_card);
 235        *card_ret = card;
 236        return 0;
 237
 238      __error_ctl:
 239        snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
 240      __error:
 241        kfree(card);
 242        return err;
 243}
 244EXPORT_SYMBOL(snd_card_create);
 245
 246/* return non-zero if a card is already locked */
 247int snd_card_locked(int card)
 248{
 249        int locked;
 250
 251        mutex_lock(&snd_card_mutex);
 252        locked = snd_cards_lock & (1 << card);
 253        mutex_unlock(&snd_card_mutex);
 254        return locked;
 255}
 256
 257static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
 258{
 259        return -ENODEV;
 260}
 261
 262static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
 263                                   size_t count, loff_t *offset)
 264{
 265        return -ENODEV;
 266}
 267
 268static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
 269                                    size_t count, loff_t *offset)
 270{
 271        return -ENODEV;
 272}
 273
 274static int snd_disconnect_release(struct inode *inode, struct file *file)
 275{
 276        struct snd_monitor_file *df = NULL, *_df;
 277
 278        spin_lock(&shutdown_lock);
 279        list_for_each_entry(_df, &shutdown_files, shutdown_list) {
 280                if (_df->file == file) {
 281                        df = _df;
 282                        list_del_init(&df->shutdown_list);
 283                        break;
 284                }
 285        }
 286        spin_unlock(&shutdown_lock);
 287
 288        if (likely(df)) {
 289                if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
 290                        df->disconnected_f_op->fasync(-1, file, 0);
 291                return df->disconnected_f_op->release(inode, file);
 292        }
 293
 294        panic("%s(%p, %p) failed!", __func__, inode, file);
 295}
 296
 297static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 298{
 299        return POLLERR | POLLNVAL;
 300}
 301
 302static long snd_disconnect_ioctl(struct file *file,
 303                                 unsigned int cmd, unsigned long arg)
 304{
 305        return -ENODEV;
 306}
 307
 308static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
 309{
 310        return -ENODEV;
 311}
 312
 313static int snd_disconnect_fasync(int fd, struct file *file, int on)
 314{
 315        return -ENODEV;
 316}
 317
 318static const struct file_operations snd_shutdown_f_ops =
 319{
 320        .owner =        THIS_MODULE,
 321        .llseek =       snd_disconnect_llseek,
 322        .read =         snd_disconnect_read,
 323        .write =        snd_disconnect_write,
 324        .release =      snd_disconnect_release,
 325        .poll =         snd_disconnect_poll,
 326        .unlocked_ioctl = snd_disconnect_ioctl,
 327#ifdef CONFIG_COMPAT
 328        .compat_ioctl = snd_disconnect_ioctl,
 329#endif
 330        .mmap =         snd_disconnect_mmap,
 331        .fasync =       snd_disconnect_fasync
 332};
 333
 334/**
 335 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 336 *  @card: soundcard structure
 337 *
 338 *  Disconnects all APIs from the file-operations (user space).
 339 *
 340 *  Returns zero, otherwise a negative error code.
 341 *
 342 *  Note: The current implementation replaces all active file->f_op with special
 343 *        dummy file operations (they do nothing except release).
 344 */
 345int snd_card_disconnect(struct snd_card *card)
 346{
 347        struct snd_monitor_file *mfile;
 348        int err;
 349
 350        if (!card)
 351                return -EINVAL;
 352
 353        spin_lock(&card->files_lock);
 354        if (card->shutdown) {
 355                spin_unlock(&card->files_lock);
 356                return 0;
 357        }
 358        card->shutdown = 1;
 359        spin_unlock(&card->files_lock);
 360
 361        /* phase 1: disable fops (user space) operations for ALSA API */
 362        mutex_lock(&snd_card_mutex);
 363        snd_cards[card->number] = NULL;
 364        snd_cards_lock &= ~(1 << card->number);
 365        mutex_unlock(&snd_card_mutex);
 366        
 367        /* phase 2: replace file->f_op with special dummy operations */
 368        
 369        spin_lock(&card->files_lock);
 370        list_for_each_entry(mfile, &card->files_list, list) {
 371                /* it's critical part, use endless loop */
 372                /* we have no room to fail */
 373                mfile->disconnected_f_op = mfile->file->f_op;
 374
 375                spin_lock(&shutdown_lock);
 376                list_add(&mfile->shutdown_list, &shutdown_files);
 377                spin_unlock(&shutdown_lock);
 378
 379                mfile->file->f_op = &snd_shutdown_f_ops;
 380                fops_get(mfile->file->f_op);
 381        }
 382        spin_unlock(&card->files_lock); 
 383
 384        /* phase 3: notify all connected devices about disconnection */
 385        /* at this point, they cannot respond to any calls except release() */
 386
 387#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 388        if (snd_mixer_oss_notify_callback)
 389                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
 390#endif
 391
 392        /* notify all devices that we are disconnected */
 393        err = snd_device_disconnect_all(card);
 394        if (err < 0)
 395                snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
 396
 397        snd_info_card_disconnect(card);
 398        if (card->card_dev) {
 399                device_unregister(card->card_dev);
 400                card->card_dev = NULL;
 401        }
 402#ifdef CONFIG_PM
 403        wake_up(&card->power_sleep);
 404#endif
 405        return 0;       
 406}
 407
 408EXPORT_SYMBOL(snd_card_disconnect);
 409
 410/**
 411 *  snd_card_free - frees given soundcard structure
 412 *  @card: soundcard structure
 413 *
 414 *  This function releases the soundcard structure and the all assigned
 415 *  devices automatically.  That is, you don't have to release the devices
 416 *  by yourself.
 417 *
 418 *  Returns zero. Frees all associated devices and frees the control
 419 *  interface associated to given soundcard.
 420 */
 421static int snd_card_do_free(struct snd_card *card)
 422{
 423#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 424        if (snd_mixer_oss_notify_callback)
 425                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
 426#endif
 427        if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
 428                snd_printk(KERN_ERR "unable to free all devices (pre)\n");
 429                /* Fatal, but this situation should never occur */
 430        }
 431        if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
 432                snd_printk(KERN_ERR "unable to free all devices (normal)\n");
 433                /* Fatal, but this situation should never occur */
 434        }
 435        if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
 436                snd_printk(KERN_ERR "unable to free all devices (post)\n");
 437                /* Fatal, but this situation should never occur */
 438        }
 439        if (card->private_free)
 440                card->private_free(card);
 441        snd_info_free_entry(card->proc_id);
 442        if (snd_info_card_free(card) < 0) {
 443                snd_printk(KERN_WARNING "unable to free card info\n");
 444                /* Not fatal error */
 445        }
 446        kfree(card);
 447        return 0;
 448}
 449
 450/**
 451 * snd_card_unref - release the reference counter
 452 * @card: the card instance
 453 *
 454 * Decrements the reference counter.  When it reaches to zero, wake up
 455 * the sleeper and call the destructor if needed.
 456 */
 457void snd_card_unref(struct snd_card *card)
 458{
 459        if (atomic_dec_and_test(&card->refcount)) {
 460                wake_up(&card->shutdown_sleep);
 461                if (card->free_on_last_close)
 462                        snd_card_do_free(card);
 463        }
 464}
 465EXPORT_SYMBOL(snd_card_unref);
 466
 467int snd_card_free_when_closed(struct snd_card *card)
 468{
 469        int ret;
 470
 471        atomic_inc(&card->refcount);
 472        ret = snd_card_disconnect(card);
 473        if (ret) {
 474                atomic_dec(&card->refcount);
 475                return ret;
 476        }
 477
 478        card->free_on_last_close = 1;
 479        if (atomic_dec_and_test(&card->refcount))
 480                snd_card_do_free(card);
 481        return 0;
 482}
 483
 484EXPORT_SYMBOL(snd_card_free_when_closed);
 485
 486int snd_card_free(struct snd_card *card)
 487{
 488        int ret = snd_card_disconnect(card);
 489        if (ret)
 490                return ret;
 491
 492        /* wait, until all devices are ready for the free operation */
 493        wait_event(card->shutdown_sleep, !atomic_read(&card->refcount));
 494        snd_card_do_free(card);
 495        return 0;
 496}
 497
 498EXPORT_SYMBOL(snd_card_free);
 499
 500/* retrieve the last word of shortname or longname */
 501static const char *retrieve_id_from_card_name(const char *name)
 502{
 503        const char *spos = name;
 504
 505        while (*name) {
 506                if (isspace(*name) && isalnum(name[1]))
 507                        spos = name + 1;
 508                name++;
 509        }
 510        return spos;
 511}
 512
 513/* return true if the given id string doesn't conflict any other card ids */
 514static bool card_id_ok(struct snd_card *card, const char *id)
 515{
 516        int i;
 517        if (!snd_info_check_reserved_words(id))
 518                return false;
 519        for (i = 0; i < snd_ecards_limit; i++) {
 520                if (snd_cards[i] && snd_cards[i] != card &&
 521                    !strcmp(snd_cards[i]->id, id))
 522                        return false;
 523        }
 524        return true;
 525}
 526
 527/* copy to card->id only with valid letters from nid */
 528static void copy_valid_id_string(struct snd_card *card, const char *src,
 529                                 const char *nid)
 530{
 531        char *id = card->id;
 532
 533        while (*nid && !isalnum(*nid))
 534                nid++;
 535        if (isdigit(*nid))
 536                *id++ = isalpha(*src) ? *src : 'D';
 537        while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
 538                if (isalnum(*nid))
 539                        *id++ = *nid;
 540                nid++;
 541        }
 542        *id = 0;
 543}
 544
 545/* Set card->id from the given string
 546 * If the string conflicts with other ids, add a suffix to make it unique.
 547 */
 548static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
 549                                    const char *nid)
 550{
 551        int len, loops;
 552        bool with_suffix;
 553        bool is_default = false;
 554        char *id;
 555        
 556        copy_valid_id_string(card, src, nid);
 557        id = card->id;
 558
 559 again:
 560        /* use "Default" for obviously invalid strings
 561         * ("card" conflicts with proc directories)
 562         */
 563        if (!*id || !strncmp(id, "card", 4)) {
 564                strcpy(id, "Default");
 565                is_default = true;
 566        }
 567
 568        with_suffix = false;
 569        for (loops = 0; loops < SNDRV_CARDS; loops++) {
 570                if (card_id_ok(card, id))
 571                        return; /* OK */
 572
 573                len = strlen(id);
 574                if (!with_suffix) {
 575                        /* add the "_X" suffix */
 576                        char *spos = id + len;
 577                        if (len >  sizeof(card->id) - 3)
 578                                spos = id + sizeof(card->id) - 3;
 579                        strcpy(spos, "_1");
 580                        with_suffix = true;
 581                } else {
 582                        /* modify the existing suffix */
 583                        if (id[len - 1] != '9')
 584                                id[len - 1]++;
 585                        else
 586                                id[len - 1] = 'A';
 587                }
 588        }
 589        /* fallback to the default id */
 590        if (!is_default) {
 591                *id = 0;
 592                goto again;
 593        }
 594        /* last resort... */
 595        snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
 596        if (card->proc_root->name)
 597                strcpy(card->id, card->proc_root->name);
 598}
 599
 600/**
 601 *  snd_card_set_id - set card identification name
 602 *  @card: soundcard structure
 603 *  @nid: new identification string
 604 *
 605 *  This function sets the card identification and checks for name
 606 *  collisions.
 607 */
 608void snd_card_set_id(struct snd_card *card, const char *nid)
 609{
 610        /* check if user specified own card->id */
 611        if (card->id[0] != '\0')
 612                return;
 613        mutex_lock(&snd_card_mutex);
 614        snd_card_set_id_no_lock(card, nid, nid);
 615        mutex_unlock(&snd_card_mutex);
 616}
 617EXPORT_SYMBOL(snd_card_set_id);
 618
 619static ssize_t
 620card_id_show_attr(struct device *dev,
 621                  struct device_attribute *attr, char *buf)
 622{
 623        struct snd_card *card = dev_get_drvdata(dev);
 624        return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
 625}
 626
 627static ssize_t
 628card_id_store_attr(struct device *dev, struct device_attribute *attr,
 629                   const char *buf, size_t count)
 630{
 631        struct snd_card *card = dev_get_drvdata(dev);
 632        char buf1[sizeof(card->id)];
 633        size_t copy = count > sizeof(card->id) - 1 ?
 634                                        sizeof(card->id) - 1 : count;
 635        size_t idx;
 636        int c;
 637
 638        for (idx = 0; idx < copy; idx++) {
 639                c = buf[idx];
 640                if (!isalnum(c) && c != '_' && c != '-')
 641                        return -EINVAL;
 642        }
 643        memcpy(buf1, buf, copy);
 644        buf1[copy] = '\0';
 645        mutex_lock(&snd_card_mutex);
 646        if (!card_id_ok(NULL, buf1)) {
 647                mutex_unlock(&snd_card_mutex);
 648                return -EEXIST;
 649        }
 650        strcpy(card->id, buf1);
 651        snd_info_card_id_change(card);
 652        mutex_unlock(&snd_card_mutex);
 653
 654        return count;
 655}
 656
 657static struct device_attribute card_id_attrs =
 658        __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
 659
 660static ssize_t
 661card_number_show_attr(struct device *dev,
 662                     struct device_attribute *attr, char *buf)
 663{
 664        struct snd_card *card = dev_get_drvdata(dev);
 665        return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
 666}
 667
 668static struct device_attribute card_number_attrs =
 669        __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 670
 671/**
 672 *  snd_card_register - register the soundcard
 673 *  @card: soundcard structure
 674 *
 675 *  This function registers all the devices assigned to the soundcard.
 676 *  Until calling this, the ALSA control interface is blocked from the
 677 *  external accesses.  Thus, you should call this function at the end
 678 *  of the initialization of the card.
 679 *
 680 *  Returns zero otherwise a negative error code if the registration failed.
 681 */
 682int snd_card_register(struct snd_card *card)
 683{
 684        int err;
 685
 686        if (snd_BUG_ON(!card))
 687                return -EINVAL;
 688
 689        if (!card->card_dev) {
 690                card->card_dev = device_create(sound_class, card->dev,
 691                                               MKDEV(0, 0), card,
 692                                               "card%i", card->number);
 693                if (IS_ERR(card->card_dev))
 694                        card->card_dev = NULL;
 695        }
 696
 697        if ((err = snd_device_register_all(card)) < 0)
 698                return err;
 699        mutex_lock(&snd_card_mutex);
 700        if (snd_cards[card->number]) {
 701                /* already registered */
 702                mutex_unlock(&snd_card_mutex);
 703                return 0;
 704        }
 705        if (*card->id) {
 706                /* make a unique id name from the given string */
 707                char tmpid[sizeof(card->id)];
 708                memcpy(tmpid, card->id, sizeof(card->id));
 709                snd_card_set_id_no_lock(card, tmpid, tmpid);
 710        } else {
 711                /* create an id from either shortname or longname */
 712                const char *src;
 713                src = *card->shortname ? card->shortname : card->longname;
 714                snd_card_set_id_no_lock(card, src,
 715                                        retrieve_id_from_card_name(src));
 716        }
 717        snd_cards[card->number] = card;
 718        mutex_unlock(&snd_card_mutex);
 719        init_info_for_card(card);
 720#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 721        if (snd_mixer_oss_notify_callback)
 722                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
 723#endif
 724        if (card->card_dev) {
 725                err = device_create_file(card->card_dev, &card_id_attrs);
 726                if (err < 0)
 727                        return err;
 728                err = device_create_file(card->card_dev, &card_number_attrs);
 729                if (err < 0)
 730                        return err;
 731        }
 732
 733        return 0;
 734}
 735
 736EXPORT_SYMBOL(snd_card_register);
 737
 738#ifdef CONFIG_PROC_FS
 739static struct snd_info_entry *snd_card_info_entry;
 740
 741static void snd_card_info_read(struct snd_info_entry *entry,
 742                               struct snd_info_buffer *buffer)
 743{
 744        int idx, count;
 745        struct snd_card *card;
 746
 747        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 748                mutex_lock(&snd_card_mutex);
 749                if ((card = snd_cards[idx]) != NULL) {
 750                        count++;
 751                        snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
 752                                        idx,
 753                                        card->id,
 754                                        card->driver,
 755                                        card->shortname);
 756                        snd_iprintf(buffer, "                      %s\n",
 757                                        card->longname);
 758                }
 759                mutex_unlock(&snd_card_mutex);
 760        }
 761        if (!count)
 762                snd_iprintf(buffer, "--- no soundcards ---\n");
 763}
 764
 765#ifdef CONFIG_SND_OSSEMUL
 766
 767void snd_card_info_read_oss(struct snd_info_buffer *buffer)
 768{
 769        int idx, count;
 770        struct snd_card *card;
 771
 772        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 773                mutex_lock(&snd_card_mutex);
 774                if ((card = snd_cards[idx]) != NULL) {
 775                        count++;
 776                        snd_iprintf(buffer, "%s\n", card->longname);
 777                }
 778                mutex_unlock(&snd_card_mutex);
 779        }
 780        if (!count) {
 781                snd_iprintf(buffer, "--- no soundcards ---\n");
 782        }
 783}
 784
 785#endif
 786
 787#ifdef MODULE
 788static struct snd_info_entry *snd_card_module_info_entry;
 789static void snd_card_module_info_read(struct snd_info_entry *entry,
 790                                      struct snd_info_buffer *buffer)
 791{
 792        int idx;
 793        struct snd_card *card;
 794
 795        for (idx = 0; idx < SNDRV_CARDS; idx++) {
 796                mutex_lock(&snd_card_mutex);
 797                if ((card = snd_cards[idx]) != NULL)
 798                        snd_iprintf(buffer, "%2i %s\n",
 799                                    idx, card->module->name);
 800                mutex_unlock(&snd_card_mutex);
 801        }
 802}
 803#endif
 804
 805int __init snd_card_info_init(void)
 806{
 807        struct snd_info_entry *entry;
 808
 809        entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
 810        if (! entry)
 811                return -ENOMEM;
 812        entry->c.text.read = snd_card_info_read;
 813        if (snd_info_register(entry) < 0) {
 814                snd_info_free_entry(entry);
 815                return -ENOMEM;
 816        }
 817        snd_card_info_entry = entry;
 818
 819#ifdef MODULE
 820        entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
 821        if (entry) {
 822                entry->c.text.read = snd_card_module_info_read;
 823                if (snd_info_register(entry) < 0)
 824                        snd_info_free_entry(entry);
 825                else
 826                        snd_card_module_info_entry = entry;
 827        }
 828#endif
 829
 830        return 0;
 831}
 832
 833int __exit snd_card_info_done(void)
 834{
 835        snd_info_free_entry(snd_card_info_entry);
 836#ifdef MODULE
 837        snd_info_free_entry(snd_card_module_info_entry);
 838#endif
 839        return 0;
 840}
 841
 842#endif /* CONFIG_PROC_FS */
 843
 844/**
 845 *  snd_component_add - add a component string
 846 *  @card: soundcard structure
 847 *  @component: the component id string
 848 *
 849 *  This function adds the component id string to the supported list.
 850 *  The component can be referred from the alsa-lib.
 851 *
 852 *  Returns zero otherwise a negative error code.
 853 */
 854  
 855int snd_component_add(struct snd_card *card, const char *component)
 856{
 857        char *ptr;
 858        int len = strlen(component);
 859
 860        ptr = strstr(card->components, component);
 861        if (ptr != NULL) {
 862                if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
 863                        return 1;
 864        }
 865        if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
 866                snd_BUG();
 867                return -ENOMEM;
 868        }
 869        if (card->components[0] != '\0')
 870                strcat(card->components, " ");
 871        strcat(card->components, component);
 872        return 0;
 873}
 874
 875EXPORT_SYMBOL(snd_component_add);
 876
 877/**
 878 *  snd_card_file_add - add the file to the file list of the card
 879 *  @card: soundcard structure
 880 *  @file: file pointer
 881 *
 882 *  This function adds the file to the file linked-list of the card.
 883 *  This linked-list is used to keep tracking the connection state,
 884 *  and to avoid the release of busy resources by hotplug.
 885 *
 886 *  Returns zero or a negative error code.
 887 */
 888int snd_card_file_add(struct snd_card *card, struct file *file)
 889{
 890        struct snd_monitor_file *mfile;
 891
 892        mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
 893        if (mfile == NULL)
 894                return -ENOMEM;
 895        mfile->file = file;
 896        mfile->disconnected_f_op = NULL;
 897        INIT_LIST_HEAD(&mfile->shutdown_list);
 898        spin_lock(&card->files_lock);
 899        if (card->shutdown) {
 900                spin_unlock(&card->files_lock);
 901                kfree(mfile);
 902                return -ENODEV;
 903        }
 904        list_add(&mfile->list, &card->files_list);
 905        atomic_inc(&card->refcount);
 906        spin_unlock(&card->files_lock);
 907        return 0;
 908}
 909
 910EXPORT_SYMBOL(snd_card_file_add);
 911
 912/**
 913 *  snd_card_file_remove - remove the file from the file list
 914 *  @card: soundcard structure
 915 *  @file: file pointer
 916 *
 917 *  This function removes the file formerly added to the card via
 918 *  snd_card_file_add() function.
 919 *  If all files are removed and snd_card_free_when_closed() was
 920 *  called beforehand, it processes the pending release of
 921 *  resources.
 922 *
 923 *  Returns zero or a negative error code.
 924 */
 925int snd_card_file_remove(struct snd_card *card, struct file *file)
 926{
 927        struct snd_monitor_file *mfile, *found = NULL;
 928
 929        spin_lock(&card->files_lock);
 930        list_for_each_entry(mfile, &card->files_list, list) {
 931                if (mfile->file == file) {
 932                        list_del(&mfile->list);
 933                        spin_lock(&shutdown_lock);
 934                        list_del(&mfile->shutdown_list);
 935                        spin_unlock(&shutdown_lock);
 936                        if (mfile->disconnected_f_op)
 937                                fops_put(mfile->disconnected_f_op);
 938                        found = mfile;
 939                        break;
 940                }
 941        }
 942        spin_unlock(&card->files_lock);
 943        if (!found) {
 944                snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
 945                return -ENOENT;
 946        }
 947        kfree(found);
 948        snd_card_unref(card);
 949        return 0;
 950}
 951
 952EXPORT_SYMBOL(snd_card_file_remove);
 953
 954#ifdef CONFIG_PM
 955/**
 956 *  snd_power_wait - wait until the power-state is changed.
 957 *  @card: soundcard structure
 958 *  @power_state: expected power state
 959 *
 960 *  Waits until the power-state is changed.
 961 *
 962 *  Note: the power lock must be active before call.
 963 */
 964int snd_power_wait(struct snd_card *card, unsigned int power_state)
 965{
 966        wait_queue_t wait;
 967        int result = 0;
 968
 969        /* fastpath */
 970        if (snd_power_get_state(card) == power_state)
 971                return 0;
 972        init_waitqueue_entry(&wait, current);
 973        add_wait_queue(&card->power_sleep, &wait);
 974        while (1) {
 975                if (card->shutdown) {
 976                        result = -ENODEV;
 977                        break;
 978                }
 979                if (snd_power_get_state(card) == power_state)
 980                        break;
 981                set_current_state(TASK_UNINTERRUPTIBLE);
 982                snd_power_unlock(card);
 983                schedule_timeout(30 * HZ);
 984                snd_power_lock(card);
 985        }
 986        remove_wait_queue(&card->power_sleep, &wait);
 987        return result;
 988}
 989
 990EXPORT_SYMBOL(snd_power_wait);
 991#endif /* CONFIG_PM */
 992
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.