Linux Audio

Check our new training course

Linux debugging, profiling, tracing and performance analysis training

Mar 24-27, 2025, special US time zones
Register
Loading...
v4.10.11
   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#include <linux/completion.h>
  32
  33#include <sound/core.h>
  34#include <sound/control.h>
  35#include <sound/info.h>
  36
  37/* monitor files for graceful shutdown (hotplug) */
  38struct snd_monitor_file {
  39	struct file *file;
  40	const struct file_operations *disconnected_f_op;
  41	struct list_head shutdown_list;	/* still need to shutdown */
  42	struct list_head list;	/* link of monitor files */
  43};
  44
  45static DEFINE_SPINLOCK(shutdown_lock);
  46static LIST_HEAD(shutdown_files);
  47
  48static const struct file_operations snd_shutdown_f_ops;
  49
  50/* locked for registering/using */
  51static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
  52struct snd_card *snd_cards[SNDRV_CARDS];
  53EXPORT_SYMBOL(snd_cards);
  54
  55static DEFINE_MUTEX(snd_card_mutex);
  56
  57static char *slots[SNDRV_CARDS];
  58module_param_array(slots, charp, NULL, 0444);
  59MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
  60
  61/* return non-zero if the given index is reserved for the given
  62 * module via slots option
  63 */
  64static int module_slot_match(struct module *module, int idx)
  65{
  66	int match = 1;
  67#ifdef MODULE
  68	const char *s1, *s2;
  69
  70	if (!module || !*module->name || !slots[idx])
  71		return 0;
  72
  73	s1 = module->name;
  74	s2 = slots[idx];
  75	if (*s2 == '!') {
  76		match = 0; /* negative match */
  77		s2++;
  78	}
  79	/* compare module name strings
  80	 * hyphens are handled as equivalent with underscore
  81	 */
  82	for (;;) {
  83		char c1 = *s1++;
  84		char c2 = *s2++;
  85		if (c1 == '-')
  86			c1 = '_';
  87		if (c2 == '-')
  88			c2 = '_';
  89		if (c1 != c2)
  90			return !match;
  91		if (!c1)
  92			break;
  93	}
  94#endif /* MODULE */
  95	return match;
  96}
  97
  98#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
  99int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
 100EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 101#endif
 102
 103#ifdef CONFIG_SND_PROC_FS
 104static void snd_card_id_read(struct snd_info_entry *entry,
 105			     struct snd_info_buffer *buffer)
 106{
 107	snd_iprintf(buffer, "%s\n", entry->card->id);
 108}
 109
 110static int init_info_for_card(struct snd_card *card)
 111{
 
 112	struct snd_info_entry *entry;
 113
 114	entry = snd_info_create_card_entry(card, "id", card->proc_root);
 115	if (!entry) {
 116		dev_dbg(card->dev, "unable to create card entry\n");
 117		return -ENOMEM;
 
 
 
 118	}
 119	entry->c.text.read = snd_card_id_read;
 
 
 
 
 120	card->proc_id = entry;
 121
 122	return snd_info_card_register(card);
 123}
 124#else /* !CONFIG_SND_PROC_FS */
 125#define init_info_for_card(card)
 126#endif
 127
 128static int check_empty_slot(struct module *module, int slot)
 129{
 130	return !slots[slot] || !*slots[slot];
 131}
 132
 133/* return an empty slot number (>= 0) found in the given bitmask @mask.
 134 * @mask == -1 == 0xffffffff means: take any free slot up to 32
 135 * when no slot is available, return the original @mask as is.
 136 */
 137static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
 138				 struct module *module)
 139{
 140	int slot;
 141
 142	for (slot = 0; slot < SNDRV_CARDS; slot++) {
 143		if (slot < 32 && !(mask & (1U << slot)))
 144			continue;
 145		if (!test_bit(slot, snd_cards_lock)) {
 146			if (check(module, slot))
 147				return slot; /* found */
 148		}
 149	}
 150	return mask; /* unchanged */
 151}
 152
 153/* the default release callback set in snd_device_initialize() below;
 154 * this is just NOP for now, as almost all jobs are already done in
 155 * dev_free callback of snd_device chain instead.
 156 */
 157static void default_release(struct device *dev)
 158{
 159}
 160
 161/**
 162 * snd_device_initialize - Initialize struct device for sound devices
 163 * @dev: device to initialize
 164 * @card: card to assign, optional
 165 */
 166void snd_device_initialize(struct device *dev, struct snd_card *card)
 167{
 168	device_initialize(dev);
 169	if (card)
 170		dev->parent = &card->card_dev;
 171	dev->class = sound_class;
 172	dev->release = default_release;
 173}
 174EXPORT_SYMBOL_GPL(snd_device_initialize);
 175
 176static int snd_card_do_free(struct snd_card *card);
 177static const struct attribute_group card_dev_attr_group;
 178
 179static void release_card_device(struct device *dev)
 180{
 181	snd_card_do_free(dev_to_snd_card(dev));
 182}
 183
 184/**
 185 *  snd_card_new - create and initialize a soundcard structure
 186 *  @parent: the parent device object
 187 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
 188 *  @xid: card identification (ASCII string)
 189 *  @module: top level module for locking
 190 *  @extra_size: allocate this extra size after the main soundcard structure
 191 *  @card_ret: the pointer to store the created card instance
 192 *
 193 *  Creates and initializes a soundcard structure.
 194 *
 195 *  The function allocates snd_card instance via kzalloc with the given
 196 *  space for the driver to use freely.  The allocated struct is stored
 197 *  in the given card_ret pointer.
 198 *
 199 *  Return: Zero if successful or a negative error code.
 200 */
 201int snd_card_new(struct device *parent, int idx, const char *xid,
 202		    struct module *module, int extra_size,
 203		    struct snd_card **card_ret)
 204{
 205	struct snd_card *card;
 206	int err;
 207
 208	if (snd_BUG_ON(!card_ret))
 209		return -EINVAL;
 210	*card_ret = NULL;
 211
 212	if (extra_size < 0)
 213		extra_size = 0;
 214	card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
 215	if (!card)
 216		return -ENOMEM;
 217	if (extra_size > 0)
 218		card->private_data = (char *)card + sizeof(struct snd_card);
 219	if (xid)
 220		strlcpy(card->id, xid, sizeof(card->id));
 221	err = 0;
 222	mutex_lock(&snd_card_mutex);
 223	if (idx < 0) /* first check the matching module-name slot */
 224		idx = get_slot_from_bitmask(idx, module_slot_match, module);
 225	if (idx < 0) /* if not matched, assign an empty slot */
 226		idx = get_slot_from_bitmask(idx, check_empty_slot, module);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 227	if (idx < 0)
 228		err = -ENODEV;
 229	else if (idx < snd_ecards_limit) {
 230		if (test_bit(idx, snd_cards_lock))
 231			err = -EBUSY;	/* invalid */
 232	} else if (idx >= SNDRV_CARDS)
 233		err = -ENODEV;
 234	if (err < 0) {
 235		mutex_unlock(&snd_card_mutex);
 236		dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
 237			 idx, snd_ecards_limit - 1, err);
 238		kfree(card);
 239		return err;
 240	}
 241	set_bit(idx, snd_cards_lock);		/* lock it */
 242	if (idx >= snd_ecards_limit)
 243		snd_ecards_limit = idx + 1; /* increase the limit */
 244	mutex_unlock(&snd_card_mutex);
 245	card->dev = parent;
 246	card->number = idx;
 247	card->module = module;
 248	INIT_LIST_HEAD(&card->devices);
 249	init_rwsem(&card->controls_rwsem);
 250	rwlock_init(&card->ctl_files_rwlock);
 251	mutex_init(&card->user_ctl_lock);
 252	INIT_LIST_HEAD(&card->controls);
 253	INIT_LIST_HEAD(&card->ctl_files);
 254	spin_lock_init(&card->files_lock);
 255	INIT_LIST_HEAD(&card->files_list);
 
 256#ifdef CONFIG_PM
 257	mutex_init(&card->power_lock);
 258	init_waitqueue_head(&card->power_sleep);
 259#endif
 260
 261	device_initialize(&card->card_dev);
 262	card->card_dev.parent = parent;
 263	card->card_dev.class = sound_class;
 264	card->card_dev.release = release_card_device;
 265	card->card_dev.groups = card->dev_groups;
 266	card->dev_groups[0] = &card_dev_attr_group;
 267	err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
 268	if (err < 0)
 269		goto __error;
 270
 271	snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s",
 272		 dev_driver_string(card->dev), dev_name(&card->card_dev));
 273
 274	/* the control interface cannot be accessed from the user space until */
 275	/* snd_cards_bitmask and snd_cards are set with snd_card_register */
 276	err = snd_ctl_create(card);
 277	if (err < 0) {
 278		dev_err(parent, "unable to register control minors\n");
 279		goto __error;
 280	}
 281	err = snd_info_card_create(card);
 282	if (err < 0) {
 283		dev_err(parent, "unable to create card info\n");
 284		goto __error_ctl;
 285	}
 
 
 286	*card_ret = card;
 287	return 0;
 288
 289      __error_ctl:
 290	snd_device_free_all(card);
 291      __error:
 292	put_device(&card->card_dev);
 293  	return err;
 294}
 295EXPORT_SYMBOL(snd_card_new);
 296
 297/* return non-zero if a card is already locked */
 298int snd_card_locked(int card)
 299{
 300	int locked;
 301
 302	mutex_lock(&snd_card_mutex);
 303	locked = test_bit(card, snd_cards_lock);
 304	mutex_unlock(&snd_card_mutex);
 305	return locked;
 306}
 307
 308static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
 309{
 310	return -ENODEV;
 311}
 312
 313static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
 314				   size_t count, loff_t *offset)
 315{
 316	return -ENODEV;
 317}
 318
 319static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
 320				    size_t count, loff_t *offset)
 321{
 322	return -ENODEV;
 323}
 324
 325static int snd_disconnect_release(struct inode *inode, struct file *file)
 326{
 327	struct snd_monitor_file *df = NULL, *_df;
 328
 329	spin_lock(&shutdown_lock);
 330	list_for_each_entry(_df, &shutdown_files, shutdown_list) {
 331		if (_df->file == file) {
 332			df = _df;
 333			list_del_init(&df->shutdown_list);
 334			break;
 335		}
 336	}
 337	spin_unlock(&shutdown_lock);
 338
 339	if (likely(df)) {
 340		if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
 341			df->disconnected_f_op->fasync(-1, file, 0);
 342		return df->disconnected_f_op->release(inode, file);
 343	}
 344
 345	panic("%s(%p, %p) failed!", __func__, inode, file);
 346}
 347
 348static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
 349{
 350	return POLLERR | POLLNVAL;
 351}
 352
 353static long snd_disconnect_ioctl(struct file *file,
 354				 unsigned int cmd, unsigned long arg)
 355{
 356	return -ENODEV;
 357}
 358
 359static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
 360{
 361	return -ENODEV;
 362}
 363
 364static int snd_disconnect_fasync(int fd, struct file *file, int on)
 365{
 366	return -ENODEV;
 367}
 368
 369static const struct file_operations snd_shutdown_f_ops =
 370{
 371	.owner = 	THIS_MODULE,
 372	.llseek =	snd_disconnect_llseek,
 373	.read = 	snd_disconnect_read,
 374	.write =	snd_disconnect_write,
 375	.release =	snd_disconnect_release,
 376	.poll =		snd_disconnect_poll,
 377	.unlocked_ioctl = snd_disconnect_ioctl,
 378#ifdef CONFIG_COMPAT
 379	.compat_ioctl = snd_disconnect_ioctl,
 380#endif
 381	.mmap =		snd_disconnect_mmap,
 382	.fasync =	snd_disconnect_fasync
 383};
 384
 385/**
 386 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 387 *  @card: soundcard structure
 388 *
 389 *  Disconnects all APIs from the file-operations (user space).
 390 *
 391 *  Return: Zero, otherwise a negative error code.
 392 *
 393 *  Note: The current implementation replaces all active file->f_op with special
 394 *        dummy file operations (they do nothing except release).
 395 */
 396int snd_card_disconnect(struct snd_card *card)
 397{
 398	struct snd_monitor_file *mfile;
 
 399
 400	if (!card)
 401		return -EINVAL;
 402
 403	spin_lock(&card->files_lock);
 404	if (card->shutdown) {
 405		spin_unlock(&card->files_lock);
 406		return 0;
 407	}
 408	card->shutdown = 1;
 409	spin_unlock(&card->files_lock);
 410
 411	/* phase 1: disable fops (user space) operations for ALSA API */
 412	mutex_lock(&snd_card_mutex);
 413	snd_cards[card->number] = NULL;
 414	clear_bit(card->number, snd_cards_lock);
 415	mutex_unlock(&snd_card_mutex);
 416	
 417	/* phase 2: replace file->f_op with special dummy operations */
 418	
 419	spin_lock(&card->files_lock);
 420	list_for_each_entry(mfile, &card->files_list, list) {
 421		/* it's critical part, use endless loop */
 422		/* we have no room to fail */
 423		mfile->disconnected_f_op = mfile->file->f_op;
 424
 425		spin_lock(&shutdown_lock);
 426		list_add(&mfile->shutdown_list, &shutdown_files);
 427		spin_unlock(&shutdown_lock);
 428
 429		mfile->file->f_op = &snd_shutdown_f_ops;
 430		fops_get(mfile->file->f_op);
 431	}
 432	spin_unlock(&card->files_lock);	
 433
 434	/* phase 3: notify all connected devices about disconnection */
 435	/* at this point, they cannot respond to any calls except release() */
 436
 437#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
 438	if (snd_mixer_oss_notify_callback)
 439		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
 440#endif
 441
 442	/* notify all devices that we are disconnected */
 443	snd_device_disconnect_all(card);
 
 
 444
 445	snd_info_card_disconnect(card);
 446	if (card->registered) {
 447		device_del(&card->card_dev);
 448		card->registered = false;
 449	}
 450#ifdef CONFIG_PM
 451	wake_up(&card->power_sleep);
 452#endif
 453	return 0;	
 454}
 455
 456EXPORT_SYMBOL(snd_card_disconnect);
 457
 
 
 
 
 
 
 
 
 
 
 
 458static int snd_card_do_free(struct snd_card *card)
 459{
 460#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
 461	if (snd_mixer_oss_notify_callback)
 462		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
 463#endif
 464	snd_device_free_all(card);
 
 
 
 
 
 
 
 
 
 
 
 465	if (card->private_free)
 466		card->private_free(card);
 467	snd_info_free_entry(card->proc_id);
 468	if (snd_info_card_free(card) < 0) {
 469		dev_warn(card->dev, "unable to free card info\n");
 470		/* Not fatal error */
 471	}
 472	if (card->release_completion)
 473		complete(card->release_completion);
 474	kfree(card);
 475	return 0;
 476}
 477
 478/**
 479 * snd_card_free_when_closed - Disconnect the card, free it later eventually
 480 * @card: soundcard structure
 481 *
 482 * Unlike snd_card_free(), this function doesn't try to release the card
 483 * resource immediately, but tries to disconnect at first.  When the card
 484 * is still in use, the function returns before freeing the resources.
 485 * The card resources will be freed when the refcount gets to zero.
 486 */
 487int snd_card_free_when_closed(struct snd_card *card)
 488{
 
 489	int ret = snd_card_disconnect(card);
 490	if (ret)
 491		return ret;
 492	put_device(&card->card_dev);
 
 
 
 
 
 
 
 
 
 493	return 0;
 494}
 
 495EXPORT_SYMBOL(snd_card_free_when_closed);
 496
 497/**
 498 * snd_card_free - frees given soundcard structure
 499 * @card: soundcard structure
 500 *
 501 * This function releases the soundcard structure and the all assigned
 502 * devices automatically.  That is, you don't have to release the devices
 503 * by yourself.
 504 *
 505 * This function waits until the all resources are properly released.
 506 *
 507 * Return: Zero. Frees all associated devices and frees the control
 508 * interface associated to given soundcard.
 509 */
 510int snd_card_free(struct snd_card *card)
 511{
 512	struct completion released;
 513	int ret;
 514
 515	init_completion(&released);
 516	card->release_completion = &released;
 517	ret = snd_card_free_when_closed(card);
 518	if (ret)
 519		return ret;
 
 520	/* wait, until all devices are ready for the free operation */
 521	wait_for_completion(&released);
 
 522	return 0;
 523}
 524EXPORT_SYMBOL(snd_card_free);
 525
 526/* retrieve the last word of shortname or longname */
 527static const char *retrieve_id_from_card_name(const char *name)
 528{
 529	const char *spos = name;
 530
 531	while (*name) {
 532		if (isspace(*name) && isalnum(name[1]))
 533			spos = name + 1;
 534		name++;
 535	}
 536	return spos;
 537}
 538
 539/* return true if the given id string doesn't conflict any other card ids */
 540static bool card_id_ok(struct snd_card *card, const char *id)
 541{
 542	int i;
 543	if (!snd_info_check_reserved_words(id))
 544		return false;
 545	for (i = 0; i < snd_ecards_limit; i++) {
 546		if (snd_cards[i] && snd_cards[i] != card &&
 547		    !strcmp(snd_cards[i]->id, id))
 548			return false;
 549	}
 550	return true;
 551}
 552
 553/* copy to card->id only with valid letters from nid */
 554static void copy_valid_id_string(struct snd_card *card, const char *src,
 555				 const char *nid)
 556{
 557	char *id = card->id;
 558
 559	while (*nid && !isalnum(*nid))
 560		nid++;
 561	if (isdigit(*nid))
 562		*id++ = isalpha(*src) ? *src : 'D';
 563	while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
 564		if (isalnum(*nid))
 565			*id++ = *nid;
 566		nid++;
 567	}
 568	*id = 0;
 569}
 570
 571/* Set card->id from the given string
 572 * If the string conflicts with other ids, add a suffix to make it unique.
 573 */
 574static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
 575				    const char *nid)
 576{
 577	int len, loops;
 578	bool is_default = false;
 579	char *id;
 580	
 581	copy_valid_id_string(card, src, nid);
 
 
 
 
 
 
 
 
 
 
 582	id = card->id;
 
 
 
 
 
 
 
 
 
 
 583
 584 again:
 585	/* use "Default" for obviously invalid strings
 586	 * ("card" conflicts with proc directories)
 587	 */
 588	if (!*id || !strncmp(id, "card", 4)) {
 589		strcpy(id, "Default");
 590		is_default = true;
 591	}
 592
 593	len = strlen(id);
 594	for (loops = 0; loops < SNDRV_CARDS; loops++) {
 595		char *spos;
 596		char sfxstr[5]; /* "_012" */
 597		int sfxlen;
 598
 599		if (card_id_ok(card, id))
 600			return; /* OK */
 601
 602		/* Add _XYZ suffix */
 603		sprintf(sfxstr, "_%X", loops + 1);
 604		sfxlen = strlen(sfxstr);
 605		if (len + sfxlen >= sizeof(card->id))
 606			spos = id + sizeof(card->id) - sfxlen - 1;
 607		else
 608			spos = id + len;
 609		strcpy(spos, sfxstr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 610	}
 611	/* fallback to the default id */
 612	if (!is_default) {
 613		*id = 0;
 614		goto again;
 615	}
 616	/* last resort... */
 617	dev_err(card->dev, "unable to set card id (%s)\n", id);
 618	if (card->proc_root->name)
 619		strlcpy(card->id, card->proc_root->name, sizeof(card->id));
 620}
 621
 622/**
 623 *  snd_card_set_id - set card identification name
 624 *  @card: soundcard structure
 625 *  @nid: new identification string
 626 *
 627 *  This function sets the card identification and checks for name
 628 *  collisions.
 629 */
 630void snd_card_set_id(struct snd_card *card, const char *nid)
 631{
 632	/* check if user specified own card->id */
 633	if (card->id[0] != '\0')
 634		return;
 635	mutex_lock(&snd_card_mutex);
 636	snd_card_set_id_no_lock(card, nid, nid);
 637	mutex_unlock(&snd_card_mutex);
 638}
 639EXPORT_SYMBOL(snd_card_set_id);
 640
 641static ssize_t
 642card_id_show_attr(struct device *dev,
 643		  struct device_attribute *attr, char *buf)
 644{
 645	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
 646	return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
 647}
 648
 649static ssize_t
 650card_id_store_attr(struct device *dev, struct device_attribute *attr,
 651		   const char *buf, size_t count)
 652{
 653	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
 654	char buf1[sizeof(card->id)];
 655	size_t copy = count > sizeof(card->id) - 1 ?
 656					sizeof(card->id) - 1 : count;
 657	size_t idx;
 658	int c;
 659
 660	for (idx = 0; idx < copy; idx++) {
 661		c = buf[idx];
 662		if (!isalnum(c) && c != '_' && c != '-')
 663			return -EINVAL;
 664	}
 665	memcpy(buf1, buf, copy);
 666	buf1[copy] = '\0';
 667	mutex_lock(&snd_card_mutex);
 668	if (!card_id_ok(NULL, buf1)) {
 
 669		mutex_unlock(&snd_card_mutex);
 670		return -EEXIST;
 671	}
 
 
 
 
 
 
 
 
 672	strcpy(card->id, buf1);
 673	snd_info_card_id_change(card);
 
 674	mutex_unlock(&snd_card_mutex);
 675
 676	return count;
 677}
 678
 679static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
 
 680
 681static ssize_t
 682card_number_show_attr(struct device *dev,
 683		     struct device_attribute *attr, char *buf)
 684{
 685	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
 686	return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
 687}
 688
 689static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 690
 691static struct attribute *card_dev_attrs[] = {
 692	&dev_attr_id.attr,
 693	&dev_attr_number.attr,
 694	NULL
 695};
 696
 697static const struct attribute_group card_dev_attr_group = {
 698	.attrs	= card_dev_attrs,
 699};
 700
 701/**
 702 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
 703 * @card: card instance
 704 * @group: attribute group to append
 705 */
 706int snd_card_add_dev_attr(struct snd_card *card,
 707			  const struct attribute_group *group)
 708{
 709	int i;
 710
 711	/* loop for (arraysize-1) here to keep NULL at the last entry */
 712	for (i = 0; i < ARRAY_SIZE(card->dev_groups) - 1; i++) {
 713		if (!card->dev_groups[i]) {
 714			card->dev_groups[i] = group;
 715			return 0;
 716		}
 717	}
 718
 719	dev_err(card->dev, "Too many groups assigned\n");
 720	return -ENOSPC;
 721};
 722EXPORT_SYMBOL_GPL(snd_card_add_dev_attr);
 723
 724/**
 725 *  snd_card_register - register the soundcard
 726 *  @card: soundcard structure
 727 *
 728 *  This function registers all the devices assigned to the soundcard.
 729 *  Until calling this, the ALSA control interface is blocked from the
 730 *  external accesses.  Thus, you should call this function at the end
 731 *  of the initialization of the card.
 732 *
 733 *  Return: Zero otherwise a negative error code if the registration failed.
 734 */
 735int snd_card_register(struct snd_card *card)
 736{
 737	int err;
 738
 739	if (snd_BUG_ON(!card))
 740		return -EINVAL;
 741
 742	if (!card->registered) {
 743		err = device_add(&card->card_dev);
 744		if (err < 0)
 745			return err;
 746		card->registered = true;
 
 747	}
 748
 749	if ((err = snd_device_register_all(card)) < 0)
 750		return err;
 751	mutex_lock(&snd_card_mutex);
 752	if (snd_cards[card->number]) {
 753		/* already registered */
 754		mutex_unlock(&snd_card_mutex);
 755		return snd_info_card_register(card); /* register pending info */
 756	}
 757	if (*card->id) {
 758		/* make a unique id name from the given string */
 759		char tmpid[sizeof(card->id)];
 760		memcpy(tmpid, card->id, sizeof(card->id));
 761		snd_card_set_id_no_lock(card, tmpid, tmpid);
 762	} else {
 763		/* create an id from either shortname or longname */
 764		const char *src;
 765		src = *card->shortname ? card->shortname : card->longname;
 766		snd_card_set_id_no_lock(card, src,
 767					retrieve_id_from_card_name(src));
 768	}
 
 769	snd_cards[card->number] = card;
 770	mutex_unlock(&snd_card_mutex);
 771	init_info_for_card(card);
 772#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
 773	if (snd_mixer_oss_notify_callback)
 774		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
 775#endif
 
 
 
 
 
 
 
 
 
 776	return 0;
 777}
 778
 779EXPORT_SYMBOL(snd_card_register);
 780
 781#ifdef CONFIG_SND_PROC_FS
 
 
 782static void snd_card_info_read(struct snd_info_entry *entry,
 783			       struct snd_info_buffer *buffer)
 784{
 785	int idx, count;
 786	struct snd_card *card;
 787
 788	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 789		mutex_lock(&snd_card_mutex);
 790		if ((card = snd_cards[idx]) != NULL) {
 791			count++;
 792			snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
 793					idx,
 794					card->id,
 795					card->driver,
 796					card->shortname);
 797			snd_iprintf(buffer, "                      %s\n",
 798					card->longname);
 799		}
 800		mutex_unlock(&snd_card_mutex);
 801	}
 802	if (!count)
 803		snd_iprintf(buffer, "--- no soundcards ---\n");
 804}
 805
 806#ifdef CONFIG_SND_OSSEMUL
 
 807void snd_card_info_read_oss(struct snd_info_buffer *buffer)
 808{
 809	int idx, count;
 810	struct snd_card *card;
 811
 812	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
 813		mutex_lock(&snd_card_mutex);
 814		if ((card = snd_cards[idx]) != NULL) {
 815			count++;
 816			snd_iprintf(buffer, "%s\n", card->longname);
 817		}
 818		mutex_unlock(&snd_card_mutex);
 819	}
 820	if (!count) {
 821		snd_iprintf(buffer, "--- no soundcards ---\n");
 822	}
 823}
 824
 825#endif
 826
 827#ifdef MODULE
 
 828static void snd_card_module_info_read(struct snd_info_entry *entry,
 829				      struct snd_info_buffer *buffer)
 830{
 831	int idx;
 832	struct snd_card *card;
 833
 834	for (idx = 0; idx < SNDRV_CARDS; idx++) {
 835		mutex_lock(&snd_card_mutex);
 836		if ((card = snd_cards[idx]) != NULL)
 837			snd_iprintf(buffer, "%2i %s\n",
 838				    idx, card->module->name);
 839		mutex_unlock(&snd_card_mutex);
 840	}
 841}
 842#endif
 843
 844int __init snd_card_info_init(void)
 845{
 846	struct snd_info_entry *entry;
 847
 848	entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
 849	if (! entry)
 850		return -ENOMEM;
 851	entry->c.text.read = snd_card_info_read;
 852	if (snd_info_register(entry) < 0)
 853		return -ENOMEM; /* freed in error path */
 
 
 
 854
 855#ifdef MODULE
 856	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
 857	if (!entry)
 858		return -ENOMEM;
 859	entry->c.text.read = snd_card_module_info_read;
 860	if (snd_info_register(entry) < 0)
 861		return -ENOMEM; /* freed in error path */
 
 
 862#endif
 863
 864	return 0;
 865}
 866#endif /* CONFIG_SND_PROC_FS */
 
 
 
 
 
 
 
 
 
 
 867
 868/**
 869 *  snd_component_add - add a component string
 870 *  @card: soundcard structure
 871 *  @component: the component id string
 872 *
 873 *  This function adds the component id string to the supported list.
 874 *  The component can be referred from the alsa-lib.
 875 *
 876 *  Return: Zero otherwise a negative error code.
 877 */
 878  
 879int snd_component_add(struct snd_card *card, const char *component)
 880{
 881	char *ptr;
 882	int len = strlen(component);
 883
 884	ptr = strstr(card->components, component);
 885	if (ptr != NULL) {
 886		if (ptr[len] == '\0' || ptr[len] == ' ')	/* already there */
 887			return 1;
 888	}
 889	if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
 890		snd_BUG();
 891		return -ENOMEM;
 892	}
 893	if (card->components[0] != '\0')
 894		strcat(card->components, " ");
 895	strcat(card->components, component);
 896	return 0;
 897}
 898
 899EXPORT_SYMBOL(snd_component_add);
 900
 901/**
 902 *  snd_card_file_add - add the file to the file list of the card
 903 *  @card: soundcard structure
 904 *  @file: file pointer
 905 *
 906 *  This function adds the file to the file linked-list of the card.
 907 *  This linked-list is used to keep tracking the connection state,
 908 *  and to avoid the release of busy resources by hotplug.
 909 *
 910 *  Return: zero or a negative error code.
 911 */
 912int snd_card_file_add(struct snd_card *card, struct file *file)
 913{
 914	struct snd_monitor_file *mfile;
 915
 916	mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
 917	if (mfile == NULL)
 918		return -ENOMEM;
 919	mfile->file = file;
 920	mfile->disconnected_f_op = NULL;
 921	INIT_LIST_HEAD(&mfile->shutdown_list);
 922	spin_lock(&card->files_lock);
 923	if (card->shutdown) {
 924		spin_unlock(&card->files_lock);
 925		kfree(mfile);
 926		return -ENODEV;
 927	}
 928	list_add(&mfile->list, &card->files_list);
 929	get_device(&card->card_dev);
 930	spin_unlock(&card->files_lock);
 931	return 0;
 932}
 933
 934EXPORT_SYMBOL(snd_card_file_add);
 935
 936/**
 937 *  snd_card_file_remove - remove the file from the file list
 938 *  @card: soundcard structure
 939 *  @file: file pointer
 940 *
 941 *  This function removes the file formerly added to the card via
 942 *  snd_card_file_add() function.
 943 *  If all files are removed and snd_card_free_when_closed() was
 944 *  called beforehand, it processes the pending release of
 945 *  resources.
 946 *
 947 *  Return: Zero or a negative error code.
 948 */
 949int snd_card_file_remove(struct snd_card *card, struct file *file)
 950{
 951	struct snd_monitor_file *mfile, *found = NULL;
 
 952
 953	spin_lock(&card->files_lock);
 954	list_for_each_entry(mfile, &card->files_list, list) {
 955		if (mfile->file == file) {
 956			list_del(&mfile->list);
 957			spin_lock(&shutdown_lock);
 958			list_del(&mfile->shutdown_list);
 959			spin_unlock(&shutdown_lock);
 960			if (mfile->disconnected_f_op)
 961				fops_put(mfile->disconnected_f_op);
 962			found = mfile;
 963			break;
 964		}
 965	}
 
 
 966	spin_unlock(&card->files_lock);
 
 
 
 
 
 967	if (!found) {
 968		dev_err(card->dev, "card file remove problem (%p)\n", file);
 969		return -ENOENT;
 970	}
 971	kfree(found);
 972	put_device(&card->card_dev);
 973	return 0;
 974}
 975
 976EXPORT_SYMBOL(snd_card_file_remove);
 977
 978#ifdef CONFIG_PM
 979/**
 980 *  snd_power_wait - wait until the power-state is changed.
 981 *  @card: soundcard structure
 982 *  @power_state: expected power state
 983 *
 984 *  Waits until the power-state is changed.
 985 *
 986 *  Return: Zero if successful, or a negative error code.
 987 *
 988 *  Note: the power lock must be active before call.
 989 */
 990int snd_power_wait(struct snd_card *card, unsigned int power_state)
 991{
 992	wait_queue_t wait;
 993	int result = 0;
 994
 995	/* fastpath */
 996	if (snd_power_get_state(card) == power_state)
 997		return 0;
 998	init_waitqueue_entry(&wait, current);
 999	add_wait_queue(&card->power_sleep, &wait);
1000	while (1) {
1001		if (card->shutdown) {
1002			result = -ENODEV;
1003			break;
1004		}
1005		if (snd_power_get_state(card) == power_state)
1006			break;
1007		set_current_state(TASK_UNINTERRUPTIBLE);
1008		snd_power_unlock(card);
1009		schedule_timeout(30 * HZ);
1010		snd_power_lock(card);
1011	}
1012	remove_wait_queue(&card->power_sleep, &wait);
1013	return result;
1014}
1015
1016EXPORT_SYMBOL(snd_power_wait);
1017#endif /* CONFIG_PM */
v3.1
  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/file.h>
 25#include <linux/slab.h>
 26#include <linux/time.h>
 27#include <linux/ctype.h>
 28#include <linux/pm.h>
 
 29
 30#include <sound/core.h>
 31#include <sound/control.h>
 32#include <sound/info.h>
 33
 34/* monitor files for graceful shutdown (hotplug) */
 35struct snd_monitor_file {
 36	struct file *file;
 37	const struct file_operations *disconnected_f_op;
 38	struct list_head shutdown_list;	/* still need to shutdown */
 39	struct list_head list;	/* link of monitor files */
 40};
 41
 42static DEFINE_SPINLOCK(shutdown_lock);
 43static LIST_HEAD(shutdown_files);
 44
 45static const struct file_operations snd_shutdown_f_ops;
 46
 47static unsigned int snd_cards_lock;	/* locked for registering/using */
 
 48struct snd_card *snd_cards[SNDRV_CARDS];
 49EXPORT_SYMBOL(snd_cards);
 50
 51static DEFINE_MUTEX(snd_card_mutex);
 52
 53static char *slots[SNDRV_CARDS];
 54module_param_array(slots, charp, NULL, 0444);
 55MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
 56
 57/* return non-zero if the given index is reserved for the given
 58 * module via slots option
 59 */
 60static int module_slot_match(struct module *module, int idx)
 61{
 62	int match = 1;
 63#ifdef MODULE
 64	const char *s1, *s2;
 65
 66	if (!module || !module->name || !slots[idx])
 67		return 0;
 68
 69	s1 = module->name;
 70	s2 = slots[idx];
 71	if (*s2 == '!') {
 72		match = 0; /* negative match */
 73		s2++;
 74	}
 75	/* compare module name strings
 76	 * hyphens are handled as equivalent with underscore
 77	 */
 78	for (;;) {
 79		char c1 = *s1++;
 80		char c2 = *s2++;
 81		if (c1 == '-')
 82			c1 = '_';
 83		if (c2 == '-')
 84			c2 = '_';
 85		if (c1 != c2)
 86			return !match;
 87		if (!c1)
 88			break;
 89	}
 90#endif /* MODULE */
 91	return match;
 92}
 93
 94#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 95int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
 96EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 97#endif
 98
 99#ifdef CONFIG_PROC_FS
100static void snd_card_id_read(struct snd_info_entry *entry,
101			     struct snd_info_buffer *buffer)
102{
103	snd_iprintf(buffer, "%s\n", entry->card->id);
104}
105
106static inline int init_info_for_card(struct snd_card *card)
107{
108	int err;
109	struct snd_info_entry *entry;
110
111	if ((err = snd_info_card_register(card)) < 0) {
112		snd_printd("unable to create card info\n");
113		return err;
114	}
115	if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
116		snd_printd("unable to create card entry\n");
117		return err;
118	}
119	entry->c.text.read = snd_card_id_read;
120	if (snd_info_register(entry) < 0) {
121		snd_info_free_entry(entry);
122		entry = NULL;
123	}
124	card->proc_id = entry;
125	return 0;
 
126}
127#else /* !CONFIG_PROC_FS */
128#define init_info_for_card(card)
129#endif
130
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131/**
132 *  snd_card_create - create and initialize a soundcard structure
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
133 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
134 *  @xid: card identification (ASCII string)
135 *  @module: top level module for locking
136 *  @extra_size: allocate this extra size after the main soundcard structure
137 *  @card_ret: the pointer to store the created card instance
138 *
139 *  Creates and initializes a soundcard structure.
140 *
141 *  The function allocates snd_card instance via kzalloc with the given
142 *  space for the driver to use freely.  The allocated struct is stored
143 *  in the given card_ret pointer.
144 *
145 *  Returns zero if successful or a negative error code.
146 */
147int snd_card_create(int idx, const char *xid,
148		    struct module *module, int extra_size,
149		    struct snd_card **card_ret)
150{
151	struct snd_card *card;
152	int err, idx2;
153
154	if (snd_BUG_ON(!card_ret))
155		return -EINVAL;
156	*card_ret = NULL;
157
158	if (extra_size < 0)
159		extra_size = 0;
160	card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
161	if (!card)
162		return -ENOMEM;
 
 
163	if (xid)
164		strlcpy(card->id, xid, sizeof(card->id));
165	err = 0;
166	mutex_lock(&snd_card_mutex);
167	if (idx < 0) {
168		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
169			/* idx == -1 == 0xffff means: take any free slot */
170			if (~snd_cards_lock & idx & 1<<idx2) {
171				if (module_slot_match(module, idx2)) {
172					idx = idx2;
173					break;
174				}
175			}
176	}
177	if (idx < 0) {
178		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
179			/* idx == -1 == 0xffff means: take any free slot */
180			if (~snd_cards_lock & idx & 1<<idx2) {
181				if (!slots[idx2] || !*slots[idx2]) {
182					idx = idx2;
183					break;
184				}
185			}
186	}
187	if (idx < 0)
188		err = -ENODEV;
189	else if (idx < snd_ecards_limit) {
190		if (snd_cards_lock & (1 << idx))
191			err = -EBUSY;	/* invalid */
192	} else if (idx >= SNDRV_CARDS)
193		err = -ENODEV;
194	if (err < 0) {
195		mutex_unlock(&snd_card_mutex);
196		snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
197			 idx, snd_ecards_limit - 1, err);
198		goto __error;
 
199	}
200	snd_cards_lock |= 1 << idx;		/* lock it */
201	if (idx >= snd_ecards_limit)
202		snd_ecards_limit = idx + 1; /* increase the limit */
203	mutex_unlock(&snd_card_mutex);
 
204	card->number = idx;
205	card->module = module;
206	INIT_LIST_HEAD(&card->devices);
207	init_rwsem(&card->controls_rwsem);
208	rwlock_init(&card->ctl_files_rwlock);
 
209	INIT_LIST_HEAD(&card->controls);
210	INIT_LIST_HEAD(&card->ctl_files);
211	spin_lock_init(&card->files_lock);
212	INIT_LIST_HEAD(&card->files_list);
213	init_waitqueue_head(&card->shutdown_sleep);
214#ifdef CONFIG_PM
215	mutex_init(&card->power_lock);
216	init_waitqueue_head(&card->power_sleep);
217#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218	/* the control interface cannot be accessed from the user space until */
219	/* snd_cards_bitmask and snd_cards are set with snd_card_register */
220	err = snd_ctl_create(card);
221	if (err < 0) {
222		snd_printk(KERN_ERR "unable to register control minors\n");
223		goto __error;
224	}
225	err = snd_info_card_create(card);
226	if (err < 0) {
227		snd_printk(KERN_ERR "unable to create card info\n");
228		goto __error_ctl;
229	}
230	if (extra_size > 0)
231		card->private_data = (char *)card + sizeof(struct snd_card);
232	*card_ret = card;
233	return 0;
234
235      __error_ctl:
236	snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
237      __error:
238	kfree(card);
239  	return err;
240}
241EXPORT_SYMBOL(snd_card_create);
242
243/* return non-zero if a card is already locked */
244int snd_card_locked(int card)
245{
246	int locked;
247
248	mutex_lock(&snd_card_mutex);
249	locked = snd_cards_lock & (1 << card);
250	mutex_unlock(&snd_card_mutex);
251	return locked;
252}
253
254static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
255{
256	return -ENODEV;
257}
258
259static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
260				   size_t count, loff_t *offset)
261{
262	return -ENODEV;
263}
264
265static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
266				    size_t count, loff_t *offset)
267{
268	return -ENODEV;
269}
270
271static int snd_disconnect_release(struct inode *inode, struct file *file)
272{
273	struct snd_monitor_file *df = NULL, *_df;
274
275	spin_lock(&shutdown_lock);
276	list_for_each_entry(_df, &shutdown_files, shutdown_list) {
277		if (_df->file == file) {
278			df = _df;
279			list_del_init(&df->shutdown_list);
280			break;
281		}
282	}
283	spin_unlock(&shutdown_lock);
284
285	if (likely(df)) {
286		if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
287			df->disconnected_f_op->fasync(-1, file, 0);
288		return df->disconnected_f_op->release(inode, file);
289	}
290
291	panic("%s(%p, %p) failed!", __func__, inode, file);
292}
293
294static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
295{
296	return POLLERR | POLLNVAL;
297}
298
299static long snd_disconnect_ioctl(struct file *file,
300				 unsigned int cmd, unsigned long arg)
301{
302	return -ENODEV;
303}
304
305static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
306{
307	return -ENODEV;
308}
309
310static int snd_disconnect_fasync(int fd, struct file *file, int on)
311{
312	return -ENODEV;
313}
314
315static const struct file_operations snd_shutdown_f_ops =
316{
317	.owner = 	THIS_MODULE,
318	.llseek =	snd_disconnect_llseek,
319	.read = 	snd_disconnect_read,
320	.write =	snd_disconnect_write,
321	.release =	snd_disconnect_release,
322	.poll =		snd_disconnect_poll,
323	.unlocked_ioctl = snd_disconnect_ioctl,
324#ifdef CONFIG_COMPAT
325	.compat_ioctl = snd_disconnect_ioctl,
326#endif
327	.mmap =		snd_disconnect_mmap,
328	.fasync =	snd_disconnect_fasync
329};
330
331/**
332 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
333 *  @card: soundcard structure
334 *
335 *  Disconnects all APIs from the file-operations (user space).
336 *
337 *  Returns zero, otherwise a negative error code.
338 *
339 *  Note: The current implementation replaces all active file->f_op with special
340 *        dummy file operations (they do nothing except release).
341 */
342int snd_card_disconnect(struct snd_card *card)
343{
344	struct snd_monitor_file *mfile;
345	int err;
346
347	if (!card)
348		return -EINVAL;
349
350	spin_lock(&card->files_lock);
351	if (card->shutdown) {
352		spin_unlock(&card->files_lock);
353		return 0;
354	}
355	card->shutdown = 1;
356	spin_unlock(&card->files_lock);
357
358	/* phase 1: disable fops (user space) operations for ALSA API */
359	mutex_lock(&snd_card_mutex);
360	snd_cards[card->number] = NULL;
361	snd_cards_lock &= ~(1 << card->number);
362	mutex_unlock(&snd_card_mutex);
363	
364	/* phase 2: replace file->f_op with special dummy operations */
365	
366	spin_lock(&card->files_lock);
367	list_for_each_entry(mfile, &card->files_list, list) {
368		/* it's critical part, use endless loop */
369		/* we have no room to fail */
370		mfile->disconnected_f_op = mfile->file->f_op;
371
372		spin_lock(&shutdown_lock);
373		list_add(&mfile->shutdown_list, &shutdown_files);
374		spin_unlock(&shutdown_lock);
375
376		mfile->file->f_op = &snd_shutdown_f_ops;
377		fops_get(mfile->file->f_op);
378	}
379	spin_unlock(&card->files_lock);	
380
381	/* phase 3: notify all connected devices about disconnection */
382	/* at this point, they cannot respond to any calls except release() */
383
384#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
385	if (snd_mixer_oss_notify_callback)
386		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
387#endif
388
389	/* notify all devices that we are disconnected */
390	err = snd_device_disconnect_all(card);
391	if (err < 0)
392		snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
393
394	snd_info_card_disconnect(card);
395	if (card->card_dev) {
396		device_unregister(card->card_dev);
397		card->card_dev = NULL;
398	}
399#ifdef CONFIG_PM
400	wake_up(&card->power_sleep);
401#endif
402	return 0;	
403}
404
405EXPORT_SYMBOL(snd_card_disconnect);
406
407/**
408 *  snd_card_free - frees given soundcard structure
409 *  @card: soundcard structure
410 *
411 *  This function releases the soundcard structure and the all assigned
412 *  devices automatically.  That is, you don't have to release the devices
413 *  by yourself.
414 *
415 *  Returns zero. Frees all associated devices and frees the control
416 *  interface associated to given soundcard.
417 */
418static int snd_card_do_free(struct snd_card *card)
419{
420#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
421	if (snd_mixer_oss_notify_callback)
422		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
423#endif
424	if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
425		snd_printk(KERN_ERR "unable to free all devices (pre)\n");
426		/* Fatal, but this situation should never occur */
427	}
428	if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
429		snd_printk(KERN_ERR "unable to free all devices (normal)\n");
430		/* Fatal, but this situation should never occur */
431	}
432	if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
433		snd_printk(KERN_ERR "unable to free all devices (post)\n");
434		/* Fatal, but this situation should never occur */
435	}
436	if (card->private_free)
437		card->private_free(card);
438	snd_info_free_entry(card->proc_id);
439	if (snd_info_card_free(card) < 0) {
440		snd_printk(KERN_WARNING "unable to free card info\n");
441		/* Not fatal error */
442	}
 
 
443	kfree(card);
444	return 0;
445}
446
 
 
 
 
 
 
 
 
 
447int snd_card_free_when_closed(struct snd_card *card)
448{
449	int free_now = 0;
450	int ret = snd_card_disconnect(card);
451	if (ret)
452		return ret;
453
454	spin_lock(&card->files_lock);
455	if (list_empty(&card->files_list))
456		free_now = 1;
457	else
458		card->free_on_last_close = 1;
459	spin_unlock(&card->files_lock);
460
461	if (free_now)
462		snd_card_do_free(card);
463	return 0;
464}
465
466EXPORT_SYMBOL(snd_card_free_when_closed);
467
 
 
 
 
 
 
 
 
 
 
 
 
 
468int snd_card_free(struct snd_card *card)
469{
470	int ret = snd_card_disconnect(card);
 
 
 
 
 
471	if (ret)
472		return ret;
473
474	/* wait, until all devices are ready for the free operation */
475	wait_event(card->shutdown_sleep, list_empty(&card->files_list));
476	snd_card_do_free(card);
477	return 0;
478}
 
479
480EXPORT_SYMBOL(snd_card_free);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
481
482static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
 
 
 
 
483{
484	int i, len, idx_flag = 0, loops = SNDRV_CARDS;
485	const char *spos, *src;
486	char *id;
487	
488	if (nid == NULL) {
489		id = card->shortname;
490		spos = src = id;
491		while (*id != '\0') {
492			if (*id == ' ')
493				spos = id + 1;
494			id++;
495		}
496	} else {
497		spos = src = nid;
498	}
499	id = card->id;
500	while (*spos != '\0' && !isalnum(*spos))
501		spos++;
502	if (isdigit(*spos))
503		*id++ = isalpha(src[0]) ? src[0] : 'D';
504	while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
505		if (isalnum(*spos))
506			*id++ = *spos;
507		spos++;
508	}
509	*id = '\0';
510
511	id = card->id;
512	
513	if (*id == '\0')
 
 
514		strcpy(id, "Default");
 
 
515
516	while (1) {
517	      	if (loops-- == 0) {
518			snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
519      			strcpy(card->id, card->proc_root->name);
520      			return;
521      		}
522	      	if (!snd_info_check_reserved_words(id))
523      			goto __change;
524		for (i = 0; i < snd_ecards_limit; i++) {
525			if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
526				goto __change;
527		}
528		break;
529
530	      __change:
531		len = strlen(id);
532		if (idx_flag) {
533			if (id[len-1] != '9')
534				id[len-1]++;
535			else
536				id[len-1] = 'A';
537		} else if ((size_t)len <= sizeof(card->id) - 3) {
538			strcat(id, "_1");
539			idx_flag++;
540		} else {
541			spos = id + len - 2;
542			if ((size_t)len <= sizeof(card->id) - 2)
543				spos++;
544			*(char *)spos++ = '_';
545			*(char *)spos++ = '1';
546			*(char *)spos++ = '\0';
547			idx_flag++;
548		}
549	}
 
 
 
 
 
 
 
 
 
550}
551
552/**
553 *  snd_card_set_id - set card identification name
554 *  @card: soundcard structure
555 *  @nid: new identification string
556 *
557 *  This function sets the card identification and checks for name
558 *  collisions.
559 */
560void snd_card_set_id(struct snd_card *card, const char *nid)
561{
562	/* check if user specified own card->id */
563	if (card->id[0] != '\0')
564		return;
565	mutex_lock(&snd_card_mutex);
566	snd_card_set_id_no_lock(card, nid);
567	mutex_unlock(&snd_card_mutex);
568}
569EXPORT_SYMBOL(snd_card_set_id);
570
571static ssize_t
572card_id_show_attr(struct device *dev,
573		  struct device_attribute *attr, char *buf)
574{
575	struct snd_card *card = dev_get_drvdata(dev);
576	return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
577}
578
579static ssize_t
580card_id_store_attr(struct device *dev, struct device_attribute *attr,
581		   const char *buf, size_t count)
582{
583	struct snd_card *card = dev_get_drvdata(dev);
584	char buf1[sizeof(card->id)];
585	size_t copy = count > sizeof(card->id) - 1 ?
586					sizeof(card->id) - 1 : count;
587	size_t idx;
588	int c;
589
590	for (idx = 0; idx < copy; idx++) {
591		c = buf[idx];
592		if (!isalnum(c) && c != '_' && c != '-')
593			return -EINVAL;
594	}
595	memcpy(buf1, buf, copy);
596	buf1[copy] = '\0';
597	mutex_lock(&snd_card_mutex);
598	if (!snd_info_check_reserved_words(buf1)) {
599	     __exist:
600		mutex_unlock(&snd_card_mutex);
601		return -EEXIST;
602	}
603	for (idx = 0; idx < snd_ecards_limit; idx++) {
604		if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
605			if (card == snd_cards[idx])
606				goto __ok;
607			else
608				goto __exist;
609		}
610	}
611	strcpy(card->id, buf1);
612	snd_info_card_id_change(card);
613__ok:
614	mutex_unlock(&snd_card_mutex);
615
616	return count;
617}
618
619static struct device_attribute card_id_attrs =
620	__ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
621
622static ssize_t
623card_number_show_attr(struct device *dev,
624		     struct device_attribute *attr, char *buf)
625{
626	struct snd_card *card = dev_get_drvdata(dev);
627	return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
628}
629
630static struct device_attribute card_number_attrs =
631	__ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
632
633/**
634 *  snd_card_register - register the soundcard
635 *  @card: soundcard structure
636 *
637 *  This function registers all the devices assigned to the soundcard.
638 *  Until calling this, the ALSA control interface is blocked from the
639 *  external accesses.  Thus, you should call this function at the end
640 *  of the initialization of the card.
641 *
642 *  Returns zero otherwise a negative error code if the registration failed.
643 */
644int snd_card_register(struct snd_card *card)
645{
646	int err;
647
648	if (snd_BUG_ON(!card))
649		return -EINVAL;
650
651	if (!card->card_dev) {
652		card->card_dev = device_create(sound_class, card->dev,
653					       MKDEV(0, 0), card,
654					       "card%i", card->number);
655		if (IS_ERR(card->card_dev))
656			card->card_dev = NULL;
657	}
658
659	if ((err = snd_device_register_all(card)) < 0)
660		return err;
661	mutex_lock(&snd_card_mutex);
662	if (snd_cards[card->number]) {
663		/* already registered */
664		mutex_unlock(&snd_card_mutex);
665		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
666	}
667	snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
668	snd_cards[card->number] = card;
669	mutex_unlock(&snd_card_mutex);
670	init_info_for_card(card);
671#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
672	if (snd_mixer_oss_notify_callback)
673		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
674#endif
675	if (card->card_dev) {
676		err = device_create_file(card->card_dev, &card_id_attrs);
677		if (err < 0)
678			return err;
679		err = device_create_file(card->card_dev, &card_number_attrs);
680		if (err < 0)
681			return err;
682	}
683
684	return 0;
685}
686
687EXPORT_SYMBOL(snd_card_register);
688
689#ifdef CONFIG_PROC_FS
690static struct snd_info_entry *snd_card_info_entry;
691
692static void snd_card_info_read(struct snd_info_entry *entry,
693			       struct snd_info_buffer *buffer)
694{
695	int idx, count;
696	struct snd_card *card;
697
698	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
699		mutex_lock(&snd_card_mutex);
700		if ((card = snd_cards[idx]) != NULL) {
701			count++;
702			snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
703					idx,
704					card->id,
705					card->driver,
706					card->shortname);
707			snd_iprintf(buffer, "                      %s\n",
708					card->longname);
709		}
710		mutex_unlock(&snd_card_mutex);
711	}
712	if (!count)
713		snd_iprintf(buffer, "--- no soundcards ---\n");
714}
715
716#ifdef CONFIG_SND_OSSEMUL
717
718void snd_card_info_read_oss(struct snd_info_buffer *buffer)
719{
720	int idx, count;
721	struct snd_card *card;
722
723	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
724		mutex_lock(&snd_card_mutex);
725		if ((card = snd_cards[idx]) != NULL) {
726			count++;
727			snd_iprintf(buffer, "%s\n", card->longname);
728		}
729		mutex_unlock(&snd_card_mutex);
730	}
731	if (!count) {
732		snd_iprintf(buffer, "--- no soundcards ---\n");
733	}
734}
735
736#endif
737
738#ifdef MODULE
739static struct snd_info_entry *snd_card_module_info_entry;
740static void snd_card_module_info_read(struct snd_info_entry *entry,
741				      struct snd_info_buffer *buffer)
742{
743	int idx;
744	struct snd_card *card;
745
746	for (idx = 0; idx < SNDRV_CARDS; idx++) {
747		mutex_lock(&snd_card_mutex);
748		if ((card = snd_cards[idx]) != NULL)
749			snd_iprintf(buffer, "%2i %s\n",
750				    idx, card->module->name);
751		mutex_unlock(&snd_card_mutex);
752	}
753}
754#endif
755
756int __init snd_card_info_init(void)
757{
758	struct snd_info_entry *entry;
759
760	entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
761	if (! entry)
762		return -ENOMEM;
763	entry->c.text.read = snd_card_info_read;
764	if (snd_info_register(entry) < 0) {
765		snd_info_free_entry(entry);
766		return -ENOMEM;
767	}
768	snd_card_info_entry = entry;
769
770#ifdef MODULE
771	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
772	if (entry) {
773		entry->c.text.read = snd_card_module_info_read;
774		if (snd_info_register(entry) < 0)
775			snd_info_free_entry(entry);
776		else
777			snd_card_module_info_entry = entry;
778	}
779#endif
780
781	return 0;
782}
783
784int __exit snd_card_info_done(void)
785{
786	snd_info_free_entry(snd_card_info_entry);
787#ifdef MODULE
788	snd_info_free_entry(snd_card_module_info_entry);
789#endif
790	return 0;
791}
792
793#endif /* CONFIG_PROC_FS */
794
795/**
796 *  snd_component_add - add a component string
797 *  @card: soundcard structure
798 *  @component: the component id string
799 *
800 *  This function adds the component id string to the supported list.
801 *  The component can be referred from the alsa-lib.
802 *
803 *  Returns zero otherwise a negative error code.
804 */
805  
806int snd_component_add(struct snd_card *card, const char *component)
807{
808	char *ptr;
809	int len = strlen(component);
810
811	ptr = strstr(card->components, component);
812	if (ptr != NULL) {
813		if (ptr[len] == '\0' || ptr[len] == ' ')	/* already there */
814			return 1;
815	}
816	if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
817		snd_BUG();
818		return -ENOMEM;
819	}
820	if (card->components[0] != '\0')
821		strcat(card->components, " ");
822	strcat(card->components, component);
823	return 0;
824}
825
826EXPORT_SYMBOL(snd_component_add);
827
828/**
829 *  snd_card_file_add - add the file to the file list of the card
830 *  @card: soundcard structure
831 *  @file: file pointer
832 *
833 *  This function adds the file to the file linked-list of the card.
834 *  This linked-list is used to keep tracking the connection state,
835 *  and to avoid the release of busy resources by hotplug.
836 *
837 *  Returns zero or a negative error code.
838 */
839int snd_card_file_add(struct snd_card *card, struct file *file)
840{
841	struct snd_monitor_file *mfile;
842
843	mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
844	if (mfile == NULL)
845		return -ENOMEM;
846	mfile->file = file;
847	mfile->disconnected_f_op = NULL;
848	INIT_LIST_HEAD(&mfile->shutdown_list);
849	spin_lock(&card->files_lock);
850	if (card->shutdown) {
851		spin_unlock(&card->files_lock);
852		kfree(mfile);
853		return -ENODEV;
854	}
855	list_add(&mfile->list, &card->files_list);
 
856	spin_unlock(&card->files_lock);
857	return 0;
858}
859
860EXPORT_SYMBOL(snd_card_file_add);
861
862/**
863 *  snd_card_file_remove - remove the file from the file list
864 *  @card: soundcard structure
865 *  @file: file pointer
866 *
867 *  This function removes the file formerly added to the card via
868 *  snd_card_file_add() function.
869 *  If all files are removed and snd_card_free_when_closed() was
870 *  called beforehand, it processes the pending release of
871 *  resources.
872 *
873 *  Returns zero or a negative error code.
874 */
875int snd_card_file_remove(struct snd_card *card, struct file *file)
876{
877	struct snd_monitor_file *mfile, *found = NULL;
878	int last_close = 0;
879
880	spin_lock(&card->files_lock);
881	list_for_each_entry(mfile, &card->files_list, list) {
882		if (mfile->file == file) {
883			list_del(&mfile->list);
884			spin_lock(&shutdown_lock);
885			list_del(&mfile->shutdown_list);
886			spin_unlock(&shutdown_lock);
887			if (mfile->disconnected_f_op)
888				fops_put(mfile->disconnected_f_op);
889			found = mfile;
890			break;
891		}
892	}
893	if (list_empty(&card->files_list))
894		last_close = 1;
895	spin_unlock(&card->files_lock);
896	if (last_close) {
897		wake_up(&card->shutdown_sleep);
898		if (card->free_on_last_close)
899			snd_card_do_free(card);
900	}
901	if (!found) {
902		snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
903		return -ENOENT;
904	}
905	kfree(found);
 
906	return 0;
907}
908
909EXPORT_SYMBOL(snd_card_file_remove);
910
911#ifdef CONFIG_PM
912/**
913 *  snd_power_wait - wait until the power-state is changed.
914 *  @card: soundcard structure
915 *  @power_state: expected power state
916 *
917 *  Waits until the power-state is changed.
 
 
918 *
919 *  Note: the power lock must be active before call.
920 */
921int snd_power_wait(struct snd_card *card, unsigned int power_state)
922{
923	wait_queue_t wait;
924	int result = 0;
925
926	/* fastpath */
927	if (snd_power_get_state(card) == power_state)
928		return 0;
929	init_waitqueue_entry(&wait, current);
930	add_wait_queue(&card->power_sleep, &wait);
931	while (1) {
932		if (card->shutdown) {
933			result = -ENODEV;
934			break;
935		}
936		if (snd_power_get_state(card) == power_state)
937			break;
938		set_current_state(TASK_UNINTERRUPTIBLE);
939		snd_power_unlock(card);
940		schedule_timeout(30 * HZ);
941		snd_power_lock(card);
942	}
943	remove_wait_queue(&card->power_sleep, &wait);
944	return result;
945}
946
947EXPORT_SYMBOL(snd_power_wait);
948#endif /* CONFIG_PM */