linux/sound/core/init.c
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   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#ifdef CONFIG_PM
 217        mutex_init(&card->power_lock);
 218        init_waitqueue_head(&card->power_sleep);
 219#endif
 220        /* the control interface cannot be accessed from the user space until */
 221        /* snd_cards_bitmask and snd_cards are set with snd_card_register */
 222        err = snd_ctl_create(card);
 223        if (err < 0) {
 224                snd_printk(KERN_ERR "unable to register control minors\n");
 225                goto __error;
 226        }
 227        err = snd_info_card_create(card);
 228        if (err < 0) {
 229                snd_printk(KERN_ERR "unable to create card info\n");
 230                goto __error_ctl;
 231        }
 232        if (extra_size > 0)
 233                card->private_data = (char *)card + sizeof(struct snd_card);
 234        *card_ret = card;
 235        return 0;
 236
 237      __error_ctl:
 238        snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
 239      __error:
 240        kfree(card);
 241        return err;
 242}
 243EXPORT_SYMBOL(snd_card_create);
 244
 245/* return non-zero if a card is already locked */
 246int snd_card_locked(int card)
 247{
 248        int locked;
 249
 250        mutex_lock(&snd_card_mutex);
 251        locked = snd_cards_lock & (1 << card);
 252        mutex_unlock(&snd_card_mutex);
 253        return locked;
 254}
 255
 256static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
 257{
 258        return -ENODEV;
 259}
 260
 261static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
 262                                   size_t count, loff_t *offset)
 263{
 264        return -ENODEV;
 265}
 266
 267static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
 268                                    size_t count, loff_t *offset)
 269{
 270        return -ENODEV;
 271}
 272
 273static int snd_disconnect_release(struct inode *inode, struct file *file)
 274{
 275        struct snd_monitor_file *df = NULL, *_df;
 276
 277        spin_lock(&shutdown_lock);
 278        list_for_each_entry(_df, &shutdown_files, shutdown_list) {
 279                if (_df->file == file) {
 280                        df = _df;
 281                        list_del_init(&df->shutdown_list);
 282                        break;
 283                }
 284        }
 285        spin_unlock(&shutdown_lock);
 286
 287        if (likely(df)) {
 288                if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
 289                        df->disconnected_f_op->fasync(-1, file, 0);
 290                return df->disconnected_f_op->release(inode, file);
 291        }
 292
 293        panic("%s(%p, %p) failed!", __func__, inode, file);
 294}
 295
 296static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 297{
 298        return POLLERR | POLLNVAL;
 299}
 300
 301static long snd_disconnect_ioctl(struct file *file,
 302                                 unsigned int cmd, unsigned long arg)
 303{
 304        return -ENODEV;
 305}
 306
 307static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
 308{
 309        return -ENODEV;
 310}
 311
 312static int snd_disconnect_fasync(int fd, struct file *file, int on)
 313{
 314        return -ENODEV;
 315}
 316
 317static const struct file_operations snd_shutdown_f_ops =
 318{
 319        .owner =        THIS_MODULE,
 320        .llseek =       snd_disconnect_llseek,
 321        .read =         snd_disconnect_read,
 322        .write =        snd_disconnect_write,
 323        .release =      snd_disconnect_release,
 324        .poll =         snd_disconnect_poll,
 325        .unlocked_ioctl = snd_disconnect_ioctl,
 326#ifdef CONFIG_COMPAT
 327        .compat_ioctl = snd_disconnect_ioctl,
 328#endif
 329        .mmap =         snd_disconnect_mmap,
 330        .fasync =       snd_disconnect_fasync
 331};
 332
 333/**
 334 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 335 *  @card: soundcard structure
 336 *
 337 *  Disconnects all APIs from the file-operations (user space).
 338 *
 339 *  Returns zero, otherwise a negative error code.
 340 *
 341 *  Note: The current implementation replaces all active file->f_op with special
 342 *        dummy file operations (they do nothing except release).
 343 */
 344int snd_card_disconnect(struct snd_card *card)
 345{
 346        struct snd_monitor_file *mfile;
 347        int err;
 348
 349        if (!card)
 350                return -EINVAL;
 351
 352        spin_lock(&card->files_lock);
 353        if (card->shutdown) {
 354                spin_unlock(&card->files_lock);
 355                return 0;
 356        }
 357        card->shutdown = 1;
 358        spin_unlock(&card->files_lock);
 359
 360        /* phase 1: disable fops (user space) operations for ALSA API */
 361        mutex_lock(&snd_card_mutex);
 362        snd_cards[card->number] = NULL;
 363        snd_cards_lock &= ~(1 << card->number);
 364        mutex_unlock(&snd_card_mutex);
 365        
 366        /* phase 2: replace file->f_op with special dummy operations */
 367        
 368        spin_lock(&card->files_lock);
 369        list_for_each_entry(mfile, &card->files_list, list) {
 370                /* it's critical part, use endless loop */
 371                /* we have no room to fail */
 372                mfile->disconnected_f_op = mfile->file->f_op;
 373
 374                spin_lock(&shutdown_lock);
 375                list_add(&mfile->shutdown_list, &shutdown_files);
 376                spin_unlock(&shutdown_lock);
 377
 378                mfile->file->f_op = &snd_shutdown_f_ops;
 379                fops_get(mfile->file->f_op);
 380        }
 381        spin_unlock(&card->files_lock); 
 382
 383        /* phase 3: notify all connected devices about disconnection */
 384        /* at this point, they cannot respond to any calls except release() */
 385
 386#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 387        if (snd_mixer_oss_notify_callback)
 388                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
 389#endif
 390
 391        /* notify all devices that we are disconnected */
 392        err = snd_device_disconnect_all(card);
 393        if (err < 0)
 394                snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
 395
 396        snd_info_card_disconnect(card);
 397        if (card->card_dev) {
 398                device_unregister(card->card_dev);
 399                card->card_dev = NULL;
 400        }
 401#ifdef CONFIG_PM
 402        wake_up(&card->power_sleep);
 403#endif
 404        return 0;       
 405}
 406
 407EXPORT_SYMBOL(snd_card_disconnect);
 408
 409/**
 410 *  snd_card_free - frees given soundcard structure
 411 *  @card: soundcard structure
 412 *
 413 *  This function releases the soundcard structure and the all assigned
 414 *  devices automatically.  That is, you don't have to release the devices
 415 *  by yourself.
 416 *
 417 *  Returns zero. Frees all associated devices and frees the control
 418 *  interface associated to given soundcard.
 419 */
 420static int snd_card_do_free(struct snd_card *card)
 421{
 422#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 423        if (snd_mixer_oss_notify_callback)
 424                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
 425#endif
 426        if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
 427                snd_printk(KERN_ERR "unable to free all devices (pre)\n");
 428                /* Fatal, but this situation should never occur */
 429        }
 430        if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
 431                snd_printk(KERN_ERR "unable to free all devices (normal)\n");
 432                /* Fatal, but this situation should never occur */
 433        }
 434        if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
 435                snd_printk(KERN_ERR "unable to free all devices (post)\n");
 436                /* Fatal, but this situation should never occur */
 437        }
 438        if (card->private_free)
 439                card->private_free(card);
 440        snd_info_free_entry(card->proc_id);
 441        if (snd_info_card_free(card) < 0) {
 442                snd_printk(KERN_WARNING "unable to free card info\n");
 443                /* Not fatal error */
 444        }
 445        kfree(card);
 446        return 0;
 447}
 448
 449int snd_card_free_when_closed(struct snd_card *card)
 450{
 451        int free_now = 0;
 452        int ret = snd_card_disconnect(card);
 453        if (ret)
 454                return ret;
 455
 456        spin_lock(&card->files_lock);
 457        if (list_empty(&card->files_list))
 458                free_now = 1;
 459        else
 460                card->free_on_last_close = 1;
 461        spin_unlock(&card->files_lock);
 462
 463        if (free_now)
 464                snd_card_do_free(card);
 465        return 0;
 466}
 467
 468EXPORT_SYMBOL(snd_card_free_when_closed);
 469
 470int snd_card_free(struct snd_card *card)
 471{
 472        int ret = snd_card_disconnect(card);
 473        if (ret)
 474                return ret;
 475
 476        /* wait, until all devices are ready for the free operation */
 477        wait_event(card->shutdown_sleep, list_empty(&card->files_list));
 478        snd_card_do_free(card);
 479        return 0;
 480}
 481
 482EXPORT_SYMBOL(snd_card_free);
 483
 484/* retrieve the last word of shortname or longname */
 485static const char *retrieve_id_from_card_name(const char *name)
 486{
 487        const char *spos = name;
 488
 489        while (*name) {
 490                if (isspace(*name) && isalnum(name[1]))
 491                        spos = name + 1;
 492                name++;
 493        }
 494        return spos;
 495}
 496
 497/* return true if the given id string doesn't conflict any other card ids */
 498static bool card_id_ok(struct snd_card *card, const char *id)
 499{
 500        int i;
 501        if (!snd_info_check_reserved_words(id))
 502                return false;
 503        for (i = 0; i < snd_ecards_limit; i++) {
 504                if (snd_cards[i] && snd_cards[i] != card &&
 505                    !strcmp(snd_cards[i]->id, id))
 506                        return false;
 507        }
 508        return true;
 509}
 510
 511/* copy to card->id only with valid letters from nid */
 512static void copy_valid_id_string(struct snd_card *card, const char *src,
 513                                 const char *nid)
 514{
 515        char *id = card->id;
 516
 517        while (*nid && !isalnum(*nid))
 518                nid++;
 519        if (isdigit(*nid))
 520                *id++ = isalpha(*src) ? *src : 'D';
 521        while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
 522                if (isalnum(*nid))
 523                        *id++ = *nid;
 524                nid++;
 525        }
 526        *id = 0;
 527}
 528
 529/* Set card->id from the given string
 530 * If the string conflicts with other ids, add a suffix to make it unique.
 531 */
 532static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
 533                                    const char *nid)
 534{
 535        int len, loops;
 536        bool with_suffix;
 537        bool is_default = false;
 538        char *id;
 539        
 540        copy_valid_id_string(card, src, nid);
 541        id = card->id;
 542
 543 again:
 544        /* use "Default" for obviously invalid strings
 545         * ("card" conflicts with proc directories)
 546         */
 547        if (!*id || !strncmp(id, "card", 4)) {
 548                strcpy(id, "Default");
 549                is_default = true;
 550        }
 551
 552        with_suffix = false;
 553        for (loops = 0; loops < SNDRV_CARDS; loops++) {
 554                if (card_id_ok(card, id))
 555                        return; /* OK */
 556
 557                len = strlen(id);
 558                if (!with_suffix) {
 559                        /* add the "_X" suffix */
 560                        char *spos = id + len;
 561                        if (len >  sizeof(card->id) - 3)
 562                                spos = id + sizeof(card->id) - 3;
 563                        strcpy(spos, "_1");
 564                        with_suffix = true;
 565                } else {
 566                        /* modify the existing suffix */
 567                        if (id[len - 1] != '9')
 568                                id[len - 1]++;
 569                        else
 570                                id[len - 1] = 'A';
 571                }
 572        }
 573        /* fallback to the default id */
 574        if (!is_default) {
 575                *id = 0;
 576                goto again;
 577        }
 578        /* last resort... */
 579        snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
 580        if (card->proc_root->name)
 581                strcpy(card->id, card->proc_root->name);
 582}
 583
 584/**
 585 *  snd_card_set_id - set card identification name
 586 *  @card: soundcard structure
 587 *  @nid: new identification string
 588 *
 589 *  This function sets the card identification and checks for name
 590 *  collisions.
 591 */
 592void snd_card_set_id(struct snd_card *card, const char *nid)
 593{
 594        /* check if user specified own card->id */
 595        if (card->id[0] != '\0')
 596                return;
 597        mutex_lock(&snd_card_mutex);
 598        snd_card_set_id_no_lock(card, nid, nid);
 599        mutex_unlock(&snd_card_mutex);
 600}
 601EXPORT_SYMBOL(snd_card_set_id);
 602
 603static ssize_t
 604card_id_show_attr(struct device *dev,
 605                  struct device_attribute *attr, char *buf)
 606{
 607        struct snd_card *card = dev_get_drvdata(dev);
 608        return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
 609}
 610
 611static ssize_t
 612card_id_store_attr(struct device *dev, struct device_attribute *attr,
 613                   const char *buf, size_t count)
 614{
 615        struct snd_card *card = dev_get_drvdata(dev);
 616        char buf1[sizeof(card->id)];
 617        size_t copy = count > sizeof(card->id) - 1 ?
 618                                        sizeof(card->id) - 1 : count;
 619        size_t idx;
 620        int c;
 621
 622        for (idx = 0; idx < copy; idx++) {
 623                c = buf[idx];
 624                if (!isalnum(c) && c != '_' && c != '-')
 625                        return -EINVAL;
 626        }
 627        memcpy(buf1, buf, copy);
 628        buf1[copy] = '\0';
 629        mutex_lock(&snd_card_mutex);
 630        if (!card_id_ok(NULL, buf1)) {
 631                mutex_unlock(&snd_card_mutex);
 632                return -EEXIST;
 633        }
 634        strcpy(card->id, buf1);
 635        snd_info_card_id_change(card);
 636        mutex_unlock(&snd_card_mutex);
 637
 638        return count;
 639}
 640
 641static struct device_attribute card_id_attrs =
 642        __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
 643
 644static ssize_t
 645card_number_show_attr(struct device *dev,
 646                     struct device_attribute *attr, char *buf)
 647{
 648        struct snd_card *card = dev_get_drvdata(dev);
 649        return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
 650}
 651
 652static struct device_attribute card_number_attrs =
 653        __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 654
 655/**
 656 *  snd_card_register - register the soundcard
 657 *  @card: soundcard structure
 658 *
 659 *  This function registers all the devices assigned to the soundcard.
 660 *  Until calling this, the ALSA control interface is blocked from the
 661 *  external accesses.  Thus, you should call this function at the end
 662 *  of the initialization of the card.
 663 *
 664 *  Returns zero otherwise a negative error code if the registration failed.
 665 */
 666int snd_card_register(struct snd_card *card)
 667{
 668        int err;
 669
 670        if (snd_BUG_ON(!card))
 671                return -EINVAL;
 672
 673        if (!card->card_dev) {
 674                card->card_dev = device_create(sound_class, card->dev,
 675                                               MKDEV(0, 0), card,
 676                                               "card%i", card->number);
 677                if (IS_ERR(card->card_dev))
 678                        card->card_dev = NULL;
 679        }
 680
 681        if ((err = snd_device_register_all(card)) < 0)
 682                return err;
 683        mutex_lock(&snd_card_mutex);
 684        if (snd_cards[card->number]) {
 685                /* already registered */
 686                mutex_unlock(&snd_card_mutex);
 687                return 0;
 688        }
 689        if (*card->id) {
 690                /* make a unique id name from the given string */
 691                char tmpid[sizeof(card->id)];
 692                memcpy(tmpid, card->id, sizeof(card->id));
 693                snd_card_set_id_no_lock(card, tmpid, tmpid);
 694        } else {
 695                /* create an id from either shortname or longname */
 696                const char *src;
 697                src = *card->shortname ? card->shortname : card->longname;
 698                snd_card_set_id_no_lock(card, src,
 699                                        retrieve_id_from_card_name(src));
 700        }
 701        snd_cards[card->number] = card;
 702        mutex_unlock(&snd_card_mutex);
 703        init_info_for_card(card);
 704#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 705        if (snd_mixer_oss_notify_callback)
 706                snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
 707#endif
 708        if (card->card_dev) {
 709                err = device_create_file(card->card_dev, &card_id_attrs);
 710                if (err < 0)
 711                        return err;
 712                err = device_create_file(card->card_dev, &card_number_attrs);
 713                if (err < 0)
 714                        return err;
 715        }
 716
 717        return 0;
 718}
 719
 720EXPORT_SYMBOL(snd_card_register);
 721
 722#ifdef CONFIG_PROC_FS
 723static struct snd_info_entry *snd_card_info_entry;
 724
 725static void snd_card_info_read(struct snd_info_entry *entry,
 726                               struct snd_info_buffer *buffer)
 727{
 728        int idx, count;
 729        struct snd_card *card;
 730
 731        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 732                mutex_lock(&snd_card_mutex);
 733                if ((card = snd_cards[idx]) != NULL) {
 734                        count++;
 735                        snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
 736                                        idx,
 737                                        card->id,
 738                                        card->driver,
 739                                        card->shortname);
 740                        snd_iprintf(buffer, "                      %s\n",
 741                                        card->longname);
 742                }
 743                mutex_unlock(&snd_card_mutex);
 744        }
 745        if (!count)
 746                snd_iprintf(buffer, "--- no soundcards ---\n");
 747}
 748
 749#ifdef CONFIG_SND_OSSEMUL
 750
 751void snd_card_info_read_oss(struct snd_info_buffer *buffer)
 752{
 753        int idx, count;
 754        struct snd_card *card;
 755
 756        for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 757                mutex_lock(&snd_card_mutex);
 758                if ((card = snd_cards[idx]) != NULL) {
 759                        count++;
 760                        snd_iprintf(buffer, "%s\n", card->longname);
 761                }
 762                mutex_unlock(&snd_card_mutex);
 763        }
 764        if (!count) {
 765                snd_iprintf(buffer, "--- no soundcards ---\n");
 766        }
 767}
 768
 769#endif
 770
 771#ifdef MODULE
 772static struct snd_info_entry *snd_card_module_info_entry;
 773static void snd_card_module_info_read(struct snd_info_entry *entry,
 774                                      struct snd_info_buffer *buffer)
 775{
 776        int idx;
 777        struct snd_card *card;
 778
 779        for (idx = 0; idx < SNDRV_CARDS; idx++) {
 780                mutex_lock(&snd_card_mutex);
 781                if ((card = snd_cards[idx]) != NULL)
 782                        snd_iprintf(buffer, "%2i %s\n",
 783                                    idx, card->module->name);
 784                mutex_unlock(&snd_card_mutex);
 785        }
 786}
 787#endif
 788
 789int __init snd_card_info_init(void)
 790{
 791        struct snd_info_entry *entry;
 792
 793        entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
 794        if (! entry)
 795                return -ENOMEM;
 796        entry->c.text.read = snd_card_info_read;
 797        if (snd_info_register(entry) < 0) {
 798                snd_info_free_entry(entry);
 799                return -ENOMEM;
 800        }
 801        snd_card_info_entry = entry;
 802
 803#ifdef MODULE
 804        entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
 805        if (entry) {
 806                entry->c.text.read = snd_card_module_info_read;
 807                if (snd_info_register(entry) < 0)
 808                        snd_info_free_entry(entry);
 809                else
 810                        snd_card_module_info_entry = entry;
 811        }
 812#endif
 813
 814        return 0;
 815}
 816
 817int __exit snd_card_info_done(void)
 818{
 819        snd_info_free_entry(snd_card_info_entry);
 820#ifdef MODULE
 821        snd_info_free_entry(snd_card_module_info_entry);
 822#endif
 823        return 0;
 824}
 825
 826#endif /* CONFIG_PROC_FS */
 827
 828/**
 829 *  snd_component_add - add a component string
 830 *  @card: soundcard structure
 831 *  @component: the component id string
 832 *
 833 *  This function adds the component id string to the supported list.
 834 *  The component can be referred from the alsa-lib.
 835 *
 836 *  Returns zero otherwise a negative error code.
 837 */
 838  
 839int snd_component_add(struct snd_card *card, const char *component)
 840{
 841        char *ptr;
 842        int len = strlen(component);
 843
 844        ptr = strstr(card->components, component);
 845        if (ptr != NULL) {
 846                if (ptr[len] == '\0' || ptr[len] == ' ')        /* already there */
 847                        return 1;
 848        }
 849        if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
 850                snd_BUG();
 851                return -ENOMEM;
 852        }
 853        if (card->components[0] != '\0')
 854                strcat(card->components, " ");
 855        strcat(card->components, component);
 856        return 0;
 857}
 858
 859EXPORT_SYMBOL(snd_component_add);
 860
 861/**
 862 *  snd_card_file_add - add the file to the file list of the card
 863 *  @card: soundcard structure
 864 *  @file: file pointer
 865 *
 866 *  This function adds the file to the file linked-list of the card.
 867 *  This linked-list is used to keep tracking the connection state,
 868 *  and to avoid the release of busy resources by hotplug.
 869 *
 870 *  Returns zero or a negative error code.
 871 */
 872int snd_card_file_add(struct snd_card *card, struct file *file)
 873{
 874        struct snd_monitor_file *mfile;
 875
 876        mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
 877        if (mfile == NULL)
 878                return -ENOMEM;
 879        mfile->file = file;
 880        mfile->disconnected_f_op = NULL;
 881        INIT_LIST_HEAD(&mfile->shutdown_list);
 882        spin_lock(&card->files_lock);
 883        if (card->shutdown) {
 884                spin_unlock(&card->files_lock);
 885                kfree(mfile);
 886                return -ENODEV;
 887        }
 888        list_add(&mfile->list, &card->files_list);
 889        spin_unlock(&card->files_lock);
 890        return 0;
 891}
 892
 893EXPORT_SYMBOL(snd_card_file_add);
 894
 895/**
 896 *  snd_card_file_remove - remove the file from the file list
 897 *  @card: soundcard structure
 898 *  @file: file pointer
 899 *
 900 *  This function removes the file formerly added to the card via
 901 *  snd_card_file_add() function.
 902 *  If all files are removed and snd_card_free_when_closed() was
 903 *  called beforehand, it processes the pending release of
 904 *  resources.
 905 *
 906 *  Returns zero or a negative error code.
 907 */
 908int snd_card_file_remove(struct snd_card *card, struct file *file)
 909{
 910        struct snd_monitor_file *mfile, *found = NULL;
 911        int last_close = 0;
 912
 913        spin_lock(&card->files_lock);
 914        list_for_each_entry(mfile, &card->files_list, list) {
 915                if (mfile->file == file) {
 916                        list_del(&mfile->list);
 917                        spin_lock(&shutdown_lock);
 918                        list_del(&mfile->shutdown_list);
 919                        spin_unlock(&shutdown_lock);
 920                        if (mfile->disconnected_f_op)
 921                                fops_put(mfile->disconnected_f_op);
 922                        found = mfile;
 923                        break;
 924                }
 925        }
 926        if (list_empty(&card->files_list))
 927                last_close = 1;
 928        spin_unlock(&card->files_lock);
 929        if (last_close) {
 930                wake_up(&card->shutdown_sleep);
 931                if (card->free_on_last_close)
 932                        snd_card_do_free(card);
 933        }
 934        if (!found) {
 935                snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
 936                return -ENOENT;
 937        }
 938        kfree(found);
 939        return 0;
 940}
 941
 942EXPORT_SYMBOL(snd_card_file_remove);
 943
 944#ifdef CONFIG_PM
 945/**
 946 *  snd_power_wait - wait until the power-state is changed.
 947 *  @card: soundcard structure
 948 *  @power_state: expected power state
 949 *
 950 *  Waits until the power-state is changed.
 951 *
 952 *  Note: the power lock must be active before call.
 953 */
 954int snd_power_wait(struct snd_card *card, unsigned int power_state)
 955{
 956        wait_queue_t wait;
 957        int result = 0;
 958
 959        /* fastpath */
 960        if (snd_power_get_state(card) == power_state)
 961                return 0;
 962        init_waitqueue_entry(&wait, current);
 963        add_wait_queue(&card->power_sleep, &wait);
 964        while (1) {
 965                if (card->shutdown) {
 966                        result = -ENODEV;
 967                        break;
 968                }
 969                if (snd_power_get_state(card) == power_state)
 970                        break;
 971                set_current_state(TASK_UNINTERRUPTIBLE);
 972                snd_power_unlock(card);
 973                schedule_timeout(30 * HZ);
 974                snd_power_lock(card);
 975        }
 976        remove_wait_queue(&card->power_sleep, &wait);
 977        return result;
 978}
 979
 980EXPORT_SYMBOL(snd_power_wait);
 981#endif /* CONFIG_PM */
 982
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