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-rw-r--r--sound/core/init.c948
1 files changed, 948 insertions, 0 deletions
diff --git a/sound/core/init.c b/sound/core/init.c
new file mode 100644
index 00000000..2c041bb3
--- /dev/null
+++ b/sound/core/init.c
@@ -0,0 +1,948 @@
+/*
+ * Initialization routines
+ * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/ctype.h>
+#include <linux/pm.h>
+
+#include <sound/core.h>
+#include <sound/control.h>
+#include <sound/info.h>
+
+/* monitor files for graceful shutdown (hotplug) */
+struct snd_monitor_file {
+ struct file *file;
+ const struct file_operations *disconnected_f_op;
+ struct list_head shutdown_list; /* still need to shutdown */
+ struct list_head list; /* link of monitor files */
+};
+
+static DEFINE_SPINLOCK(shutdown_lock);
+static LIST_HEAD(shutdown_files);
+
+static const struct file_operations snd_shutdown_f_ops;
+
+static unsigned int snd_cards_lock; /* locked for registering/using */
+struct snd_card *snd_cards[SNDRV_CARDS];
+EXPORT_SYMBOL(snd_cards);
+
+static DEFINE_MUTEX(snd_card_mutex);
+
+static char *slots[SNDRV_CARDS];
+module_param_array(slots, charp, NULL, 0444);
+MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
+
+/* return non-zero if the given index is reserved for the given
+ * module via slots option
+ */
+static int module_slot_match(struct module *module, int idx)
+{
+ int match = 1;
+#ifdef MODULE
+ const char *s1, *s2;
+
+ if (!module || !module->name || !slots[idx])
+ return 0;
+
+ s1 = module->name;
+ s2 = slots[idx];
+ if (*s2 == '!') {
+ match = 0; /* negative match */
+ s2++;
+ }
+ /* compare module name strings
+ * hyphens are handled as equivalent with underscore
+ */
+ for (;;) {
+ char c1 = *s1++;
+ char c2 = *s2++;
+ if (c1 == '-')
+ c1 = '_';
+ if (c2 == '-')
+ c2 = '_';
+ if (c1 != c2)
+ return !match;
+ if (!c1)
+ break;
+ }
+#endif /* MODULE */
+ return match;
+}
+
+#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
+int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
+EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
+#endif
+
+#ifdef CONFIG_PROC_FS
+static void snd_card_id_read(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer)
+{
+ snd_iprintf(buffer, "%s\n", entry->card->id);
+}
+
+static inline int init_info_for_card(struct snd_card *card)
+{
+ int err;
+ struct snd_info_entry *entry;
+
+ if ((err = snd_info_card_register(card)) < 0) {
+ snd_printd("unable to create card info\n");
+ return err;
+ }
+ if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
+ snd_printd("unable to create card entry\n");
+ return err;
+ }
+ entry->c.text.read = snd_card_id_read;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ entry = NULL;
+ }
+ card->proc_id = entry;
+ return 0;
+}
+#else /* !CONFIG_PROC_FS */
+#define init_info_for_card(card)
+#endif
+
+/**
+ * snd_card_create - create and initialize a soundcard structure
+ * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
+ * @xid: card identification (ASCII string)
+ * @module: top level module for locking
+ * @extra_size: allocate this extra size after the main soundcard structure
+ * @card_ret: the pointer to store the created card instance
+ *
+ * Creates and initializes a soundcard structure.
+ *
+ * The function allocates snd_card instance via kzalloc with the given
+ * space for the driver to use freely. The allocated struct is stored
+ * in the given card_ret pointer.
+ *
+ * Returns zero if successful or a negative error code.
+ */
+int snd_card_create(int idx, const char *xid,
+ struct module *module, int extra_size,
+ struct snd_card **card_ret)
+{
+ struct snd_card *card;
+ int err, idx2;
+
+ if (snd_BUG_ON(!card_ret))
+ return -EINVAL;
+ *card_ret = NULL;
+
+ if (extra_size < 0)
+ extra_size = 0;
+ card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
+ if (!card)
+ return -ENOMEM;
+ if (xid)
+ strlcpy(card->id, xid, sizeof(card->id));
+ err = 0;
+ mutex_lock(&snd_card_mutex);
+ if (idx < 0) {
+ for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
+ /* idx == -1 == 0xffff means: take any free slot */
+ if (~snd_cards_lock & idx & 1<<idx2) {
+ if (module_slot_match(module, idx2)) {
+ idx = idx2;
+ break;
+ }
+ }
+ }
+ if (idx < 0) {
+ for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
+ /* idx == -1 == 0xffff means: take any free slot */
+ if (~snd_cards_lock & idx & 1<<idx2) {
+ if (!slots[idx2] || !*slots[idx2]) {
+ idx = idx2;
+ break;
+ }
+ }
+ }
+ if (idx < 0)
+ err = -ENODEV;
+ else if (idx < snd_ecards_limit) {
+ if (snd_cards_lock & (1 << idx))
+ err = -EBUSY; /* invalid */
+ } else if (idx >= SNDRV_CARDS)
+ err = -ENODEV;
+ if (err < 0) {
+ mutex_unlock(&snd_card_mutex);
+ snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
+ idx, snd_ecards_limit - 1, err);
+ goto __error;
+ }
+ snd_cards_lock |= 1 << idx; /* lock it */
+ if (idx >= snd_ecards_limit)
+ snd_ecards_limit = idx + 1; /* increase the limit */
+ mutex_unlock(&snd_card_mutex);
+ card->number = idx;
+ card->module = module;
+ INIT_LIST_HEAD(&card->devices);
+ init_rwsem(&card->controls_rwsem);
+ rwlock_init(&card->ctl_files_rwlock);
+ INIT_LIST_HEAD(&card->controls);
+ INIT_LIST_HEAD(&card->ctl_files);
+ spin_lock_init(&card->files_lock);
+ INIT_LIST_HEAD(&card->files_list);
+ init_waitqueue_head(&card->shutdown_sleep);
+#ifdef CONFIG_PM
+ mutex_init(&card->power_lock);
+ init_waitqueue_head(&card->power_sleep);
+#endif
+ /* the control interface cannot be accessed from the user space until */
+ /* snd_cards_bitmask and snd_cards are set with snd_card_register */
+ err = snd_ctl_create(card);
+ if (err < 0) {
+ snd_printk(KERN_ERR "unable to register control minors\n");
+ goto __error;
+ }
+ err = snd_info_card_create(card);
+ if (err < 0) {
+ snd_printk(KERN_ERR "unable to create card info\n");
+ goto __error_ctl;
+ }
+ if (extra_size > 0)
+ card->private_data = (char *)card + sizeof(struct snd_card);
+ *card_ret = card;
+ return 0;
+
+ __error_ctl:
+ snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
+ __error:
+ kfree(card);
+ return err;
+}
+EXPORT_SYMBOL(snd_card_create);
+
+/* return non-zero if a card is already locked */
+int snd_card_locked(int card)
+{
+ int locked;
+
+ mutex_lock(&snd_card_mutex);
+ locked = snd_cards_lock & (1 << card);
+ mutex_unlock(&snd_card_mutex);
+ return locked;
+}
+
+static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
+{
+ return -ENODEV;
+}
+
+static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return -ENODEV;
+}
+
+static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return -ENODEV;
+}
+
+static int snd_disconnect_release(struct inode *inode, struct file *file)
+{
+ struct snd_monitor_file *df = NULL, *_df;
+
+ spin_lock(&shutdown_lock);
+ list_for_each_entry(_df, &shutdown_files, shutdown_list) {
+ if (_df->file == file) {
+ df = _df;
+ list_del_init(&df->shutdown_list);
+ break;
+ }
+ }
+ spin_unlock(&shutdown_lock);
+
+ if (likely(df)) {
+ if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
+ df->disconnected_f_op->fasync(-1, file, 0);
+ return df->disconnected_f_op->release(inode, file);
+ }
+
+ panic("%s(%p, %p) failed!", __func__, inode, file);
+}
+
+static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
+{
+ return POLLERR | POLLNVAL;
+}
+
+static long snd_disconnect_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ return -ENODEV;
+}
+
+static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ return -ENODEV;
+}
+
+static int snd_disconnect_fasync(int fd, struct file *file, int on)
+{
+ return -ENODEV;
+}
+
+static const struct file_operations snd_shutdown_f_ops =
+{
+ .owner = THIS_MODULE,
+ .llseek = snd_disconnect_llseek,
+ .read = snd_disconnect_read,
+ .write = snd_disconnect_write,
+ .release = snd_disconnect_release,
+ .poll = snd_disconnect_poll,
+ .unlocked_ioctl = snd_disconnect_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = snd_disconnect_ioctl,
+#endif
+ .mmap = snd_disconnect_mmap,
+ .fasync = snd_disconnect_fasync
+};
+
+/**
+ * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
+ * @card: soundcard structure
+ *
+ * Disconnects all APIs from the file-operations (user space).
+ *
+ * Returns zero, otherwise a negative error code.
+ *
+ * Note: The current implementation replaces all active file->f_op with special
+ * dummy file operations (they do nothing except release).
+ */
+int snd_card_disconnect(struct snd_card *card)
+{
+ struct snd_monitor_file *mfile;
+ int err;
+
+ if (!card)
+ return -EINVAL;
+
+ spin_lock(&card->files_lock);
+ if (card->shutdown) {
+ spin_unlock(&card->files_lock);
+ return 0;
+ }
+ card->shutdown = 1;
+ spin_unlock(&card->files_lock);
+
+ /* phase 1: disable fops (user space) operations for ALSA API */
+ mutex_lock(&snd_card_mutex);
+ snd_cards[card->number] = NULL;
+ snd_cards_lock &= ~(1 << card->number);
+ mutex_unlock(&snd_card_mutex);
+
+ /* phase 2: replace file->f_op with special dummy operations */
+
+ spin_lock(&card->files_lock);
+ list_for_each_entry(mfile, &card->files_list, list) {
+ /* it's critical part, use endless loop */
+ /* we have no room to fail */
+ mfile->disconnected_f_op = mfile->file->f_op;
+
+ spin_lock(&shutdown_lock);
+ list_add(&mfile->shutdown_list, &shutdown_files);
+ spin_unlock(&shutdown_lock);
+
+ mfile->file->f_op = &snd_shutdown_f_ops;
+ fops_get(mfile->file->f_op);
+ }
+ spin_unlock(&card->files_lock);
+
+ /* phase 3: notify all connected devices about disconnection */
+ /* at this point, they cannot respond to any calls except release() */
+
+#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
+ if (snd_mixer_oss_notify_callback)
+ snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
+#endif
+
+ /* notify all devices that we are disconnected */
+ err = snd_device_disconnect_all(card);
+ if (err < 0)
+ snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
+
+ snd_info_card_disconnect(card);
+ if (card->card_dev) {
+ device_unregister(card->card_dev);
+ card->card_dev = NULL;
+ }
+#ifdef CONFIG_PM
+ wake_up(&card->power_sleep);
+#endif
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_disconnect);
+
+/**
+ * snd_card_free - frees given soundcard structure
+ * @card: soundcard structure
+ *
+ * This function releases the soundcard structure and the all assigned
+ * devices automatically. That is, you don't have to release the devices
+ * by yourself.
+ *
+ * Returns zero. Frees all associated devices and frees the control
+ * interface associated to given soundcard.
+ */
+static int snd_card_do_free(struct snd_card *card)
+{
+#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
+ if (snd_mixer_oss_notify_callback)
+ snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
+#endif
+ if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
+ snd_printk(KERN_ERR "unable to free all devices (pre)\n");
+ /* Fatal, but this situation should never occur */
+ }
+ if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
+ snd_printk(KERN_ERR "unable to free all devices (normal)\n");
+ /* Fatal, but this situation should never occur */
+ }
+ if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
+ snd_printk(KERN_ERR "unable to free all devices (post)\n");
+ /* Fatal, but this situation should never occur */
+ }
+ if (card->private_free)
+ card->private_free(card);
+ snd_info_free_entry(card->proc_id);
+ if (snd_info_card_free(card) < 0) {
+ snd_printk(KERN_WARNING "unable to free card info\n");
+ /* Not fatal error */
+ }
+ kfree(card);
+ return 0;
+}
+
+int snd_card_free_when_closed(struct snd_card *card)
+{
+ int free_now = 0;
+ int ret = snd_card_disconnect(card);
+ if (ret)
+ return ret;
+
+ spin_lock(&card->files_lock);
+ if (list_empty(&card->files_list))
+ free_now = 1;
+ else
+ card->free_on_last_close = 1;
+ spin_unlock(&card->files_lock);
+
+ if (free_now)
+ snd_card_do_free(card);
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_free_when_closed);
+
+int snd_card_free(struct snd_card *card)
+{
+ int ret = snd_card_disconnect(card);
+ if (ret)
+ return ret;
+
+ /* wait, until all devices are ready for the free operation */
+ wait_event(card->shutdown_sleep, list_empty(&card->files_list));
+ snd_card_do_free(card);
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_free);
+
+static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
+{
+ int i, len, idx_flag = 0, loops = SNDRV_CARDS;
+ const char *spos, *src;
+ char *id;
+
+ if (nid == NULL) {
+ id = card->shortname;
+ spos = src = id;
+ while (*id != '\0') {
+ if (*id == ' ')
+ spos = id + 1;
+ id++;
+ }
+ } else {
+ spos = src = nid;
+ }
+ id = card->id;
+ while (*spos != '\0' && !isalnum(*spos))
+ spos++;
+ if (isdigit(*spos))
+ *id++ = isalpha(src[0]) ? src[0] : 'D';
+ while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
+ if (isalnum(*spos))
+ *id++ = *spos;
+ spos++;
+ }
+ *id = '\0';
+
+ id = card->id;
+
+ if (*id == '\0')
+ strcpy(id, "Default");
+
+ while (1) {
+ if (loops-- == 0) {
+ snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
+ strcpy(card->id, card->proc_root->name);
+ return;
+ }
+ if (!snd_info_check_reserved_words(id))
+ goto __change;
+ for (i = 0; i < snd_ecards_limit; i++) {
+ if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
+ goto __change;
+ }
+ break;
+
+ __change:
+ len = strlen(id);
+ if (idx_flag) {
+ if (id[len-1] != '9')
+ id[len-1]++;
+ else
+ id[len-1] = 'A';
+ } else if ((size_t)len <= sizeof(card->id) - 3) {
+ strcat(id, "_1");
+ idx_flag++;
+ } else {
+ spos = id + len - 2;
+ if ((size_t)len <= sizeof(card->id) - 2)
+ spos++;
+ *(char *)spos++ = '_';
+ *(char *)spos++ = '1';
+ *(char *)spos++ = '\0';
+ idx_flag++;
+ }
+ }
+}
+
+/**
+ * snd_card_set_id - set card identification name
+ * @card: soundcard structure
+ * @nid: new identification string
+ *
+ * This function sets the card identification and checks for name
+ * collisions.
+ */
+void snd_card_set_id(struct snd_card *card, const char *nid)
+{
+ /* check if user specified own card->id */
+ if (card->id[0] != '\0')
+ return;
+ mutex_lock(&snd_card_mutex);
+ snd_card_set_id_no_lock(card, nid);
+ mutex_unlock(&snd_card_mutex);
+}
+EXPORT_SYMBOL(snd_card_set_id);
+
+static ssize_t
+card_id_show_attr(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct snd_card *card = dev_get_drvdata(dev);
+ return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
+}
+
+static ssize_t
+card_id_store_attr(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct snd_card *card = dev_get_drvdata(dev);
+ char buf1[sizeof(card->id)];
+ size_t copy = count > sizeof(card->id) - 1 ?
+ sizeof(card->id) - 1 : count;
+ size_t idx;
+ int c;
+
+ for (idx = 0; idx < copy; idx++) {
+ c = buf[idx];
+ if (!isalnum(c) && c != '_' && c != '-')
+ return -EINVAL;
+ }
+ memcpy(buf1, buf, copy);
+ buf1[copy] = '\0';
+ mutex_lock(&snd_card_mutex);
+ if (!snd_info_check_reserved_words(buf1)) {
+ __exist:
+ mutex_unlock(&snd_card_mutex);
+ return -EEXIST;
+ }
+ for (idx = 0; idx < snd_ecards_limit; idx++) {
+ if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
+ if (card == snd_cards[idx])
+ goto __ok;
+ else
+ goto __exist;
+ }
+ }
+ strcpy(card->id, buf1);
+ snd_info_card_id_change(card);
+__ok:
+ mutex_unlock(&snd_card_mutex);
+
+ return count;
+}
+
+static struct device_attribute card_id_attrs =
+ __ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
+
+static ssize_t
+card_number_show_attr(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct snd_card *card = dev_get_drvdata(dev);
+ return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
+}
+
+static struct device_attribute card_number_attrs =
+ __ATTR(number, S_IRUGO, card_number_show_attr, NULL);
+
+/**
+ * snd_card_register - register the soundcard
+ * @card: soundcard structure
+ *
+ * This function registers all the devices assigned to the soundcard.
+ * Until calling this, the ALSA control interface is blocked from the
+ * external accesses. Thus, you should call this function at the end
+ * of the initialization of the card.
+ *
+ * Returns zero otherwise a negative error code if the registration failed.
+ */
+int snd_card_register(struct snd_card *card)
+{
+ int err;
+
+ if (snd_BUG_ON(!card))
+ return -EINVAL;
+
+ if (!card->card_dev) {
+ card->card_dev = device_create(sound_class, card->dev,
+ MKDEV(0, 0), card,
+ "card%i", card->number);
+ if (IS_ERR(card->card_dev))
+ card->card_dev = NULL;
+ }
+
+ if ((err = snd_device_register_all(card)) < 0)
+ return err;
+ mutex_lock(&snd_card_mutex);
+ if (snd_cards[card->number]) {
+ /* already registered */
+ mutex_unlock(&snd_card_mutex);
+ return 0;
+ }
+ snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
+ snd_cards[card->number] = card;
+ mutex_unlock(&snd_card_mutex);
+ init_info_for_card(card);
+#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
+ if (snd_mixer_oss_notify_callback)
+ snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
+#endif
+ if (card->card_dev) {
+ err = device_create_file(card->card_dev, &card_id_attrs);
+ if (err < 0)
+ return err;
+ err = device_create_file(card->card_dev, &card_number_attrs);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_register);
+
+#ifdef CONFIG_PROC_FS
+static struct snd_info_entry *snd_card_info_entry;
+
+static void snd_card_info_read(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer)
+{
+ int idx, count;
+ struct snd_card *card;
+
+ for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
+ mutex_lock(&snd_card_mutex);
+ if ((card = snd_cards[idx]) != NULL) {
+ count++;
+ snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
+ idx,
+ card->id,
+ card->driver,
+ card->shortname);
+ snd_iprintf(buffer, " %s\n",
+ card->longname);
+ }
+ mutex_unlock(&snd_card_mutex);
+ }
+ if (!count)
+ snd_iprintf(buffer, "--- no soundcards ---\n");
+}
+
+#ifdef CONFIG_SND_OSSEMUL
+
+void snd_card_info_read_oss(struct snd_info_buffer *buffer)
+{
+ int idx, count;
+ struct snd_card *card;
+
+ for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
+ mutex_lock(&snd_card_mutex);
+ if ((card = snd_cards[idx]) != NULL) {
+ count++;
+ snd_iprintf(buffer, "%s\n", card->longname);
+ }
+ mutex_unlock(&snd_card_mutex);
+ }
+ if (!count) {
+ snd_iprintf(buffer, "--- no soundcards ---\n");
+ }
+}
+
+#endif
+
+#ifdef MODULE
+static struct snd_info_entry *snd_card_module_info_entry;
+static void snd_card_module_info_read(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer)
+{
+ int idx;
+ struct snd_card *card;
+
+ for (idx = 0; idx < SNDRV_CARDS; idx++) {
+ mutex_lock(&snd_card_mutex);
+ if ((card = snd_cards[idx]) != NULL)
+ snd_iprintf(buffer, "%2i %s\n",
+ idx, card->module->name);
+ mutex_unlock(&snd_card_mutex);
+ }
+}
+#endif
+
+int __init snd_card_info_init(void)
+{
+ struct snd_info_entry *entry;
+
+ entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
+ if (! entry)
+ return -ENOMEM;
+ entry->c.text.read = snd_card_info_read;
+ if (snd_info_register(entry) < 0) {
+ snd_info_free_entry(entry);
+ return -ENOMEM;
+ }
+ snd_card_info_entry = entry;
+
+#ifdef MODULE
+ entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
+ if (entry) {
+ entry->c.text.read = snd_card_module_info_read;
+ if (snd_info_register(entry) < 0)
+ snd_info_free_entry(entry);
+ else
+ snd_card_module_info_entry = entry;
+ }
+#endif
+
+ return 0;
+}
+
+int __exit snd_card_info_done(void)
+{
+ snd_info_free_entry(snd_card_info_entry);
+#ifdef MODULE
+ snd_info_free_entry(snd_card_module_info_entry);
+#endif
+ return 0;
+}
+
+#endif /* CONFIG_PROC_FS */
+
+/**
+ * snd_component_add - add a component string
+ * @card: soundcard structure
+ * @component: the component id string
+ *
+ * This function adds the component id string to the supported list.
+ * The component can be referred from the alsa-lib.
+ *
+ * Returns zero otherwise a negative error code.
+ */
+
+int snd_component_add(struct snd_card *card, const char *component)
+{
+ char *ptr;
+ int len = strlen(component);
+
+ ptr = strstr(card->components, component);
+ if (ptr != NULL) {
+ if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */
+ return 1;
+ }
+ if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
+ snd_BUG();
+ return -ENOMEM;
+ }
+ if (card->components[0] != '\0')
+ strcat(card->components, " ");
+ strcat(card->components, component);
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_component_add);
+
+/**
+ * snd_card_file_add - add the file to the file list of the card
+ * @card: soundcard structure
+ * @file: file pointer
+ *
+ * This function adds the file to the file linked-list of the card.
+ * This linked-list is used to keep tracking the connection state,
+ * and to avoid the release of busy resources by hotplug.
+ *
+ * Returns zero or a negative error code.
+ */
+int snd_card_file_add(struct snd_card *card, struct file *file)
+{
+ struct snd_monitor_file *mfile;
+
+ mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
+ if (mfile == NULL)
+ return -ENOMEM;
+ mfile->file = file;
+ mfile->disconnected_f_op = NULL;
+ INIT_LIST_HEAD(&mfile->shutdown_list);
+ spin_lock(&card->files_lock);
+ if (card->shutdown) {
+ spin_unlock(&card->files_lock);
+ kfree(mfile);
+ return -ENODEV;
+ }
+ list_add(&mfile->list, &card->files_list);
+ spin_unlock(&card->files_lock);
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_file_add);
+
+/**
+ * snd_card_file_remove - remove the file from the file list
+ * @card: soundcard structure
+ * @file: file pointer
+ *
+ * This function removes the file formerly added to the card via
+ * snd_card_file_add() function.
+ * If all files are removed and snd_card_free_when_closed() was
+ * called beforehand, it processes the pending release of
+ * resources.
+ *
+ * Returns zero or a negative error code.
+ */
+int snd_card_file_remove(struct snd_card *card, struct file *file)
+{
+ struct snd_monitor_file *mfile, *found = NULL;
+ int last_close = 0;
+
+ spin_lock(&card->files_lock);
+ list_for_each_entry(mfile, &card->files_list, list) {
+ if (mfile->file == file) {
+ list_del(&mfile->list);
+ spin_lock(&shutdown_lock);
+ list_del(&mfile->shutdown_list);
+ spin_unlock(&shutdown_lock);
+ if (mfile->disconnected_f_op)
+ fops_put(mfile->disconnected_f_op);
+ found = mfile;
+ break;
+ }
+ }
+ if (list_empty(&card->files_list))
+ last_close = 1;
+ spin_unlock(&card->files_lock);
+ if (last_close) {
+ wake_up(&card->shutdown_sleep);
+ if (card->free_on_last_close)
+ snd_card_do_free(card);
+ }
+ if (!found) {
+ snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
+ return -ENOENT;
+ }
+ kfree(found);
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_card_file_remove);
+
+#ifdef CONFIG_PM
+/**
+ * snd_power_wait - wait until the power-state is changed.
+ * @card: soundcard structure
+ * @power_state: expected power state
+ *
+ * Waits until the power-state is changed.
+ *
+ * Note: the power lock must be active before call.
+ */
+int snd_power_wait(struct snd_card *card, unsigned int power_state)
+{
+ wait_queue_t wait;
+ int result = 0;
+
+ /* fastpath */
+ if (snd_power_get_state(card) == power_state)
+ return 0;
+ init_waitqueue_entry(&wait, current);
+ add_wait_queue(&card->power_sleep, &wait);
+ while (1) {
+ if (card->shutdown) {
+ result = -ENODEV;
+ break;
+ }
+ if (snd_power_get_state(card) == power_state)
+ break;
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ snd_power_unlock(card);
+ schedule_timeout(30 * HZ);
+ snd_power_lock(card);
+ }
+ remove_wait_queue(&card->power_sleep, &wait);
+ return result;
+}
+
+EXPORT_SYMBOL(snd_power_wait);
+#endif /* CONFIG_PM */