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-rw-r--r--sound/core/init.c887
1 files changed, 887 insertions, 0 deletions
diff --git a/sound/core/init.c b/sound/core/init.c
new file mode 100644
index 00000000000..3f1fa8eabb7
--- /dev/null
+++ b/sound/core/init.c
@@ -0,0 +1,887 @@
+/*
+ * Initialization routines
+ * Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
+#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/pci.h>
+#include <linux/pm.h>
+#include <sound/core.h>
+#include <sound/control.h>
+#include <sound/info.h>
+
+struct snd_shutdown_f_ops {
+ struct file_operations f_ops;
+ struct snd_shutdown_f_ops *next;
+};
+
+unsigned int snd_cards_lock = 0; /* locked for registering/using */
+snd_card_t *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL};
+DEFINE_RWLOCK(snd_card_rwlock);
+
+#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
+int (*snd_mixer_oss_notify_callback)(snd_card_t *card, int free_flag);
+#endif
+
+static void snd_card_id_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
+{
+ snd_iprintf(buffer, "%s\n", entry->card->id);
+}
+
+static void snd_card_free_thread(void * __card);
+
+/**
+ * snd_card_new - 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
+ *
+ * Creates and initializes a soundcard structure.
+ *
+ * Returns kmallocated snd_card_t structure. Creates the ALSA control interface
+ * (which is blocked until snd_card_register function is called).
+ */
+snd_card_t *snd_card_new(int idx, const char *xid,
+ struct module *module, int extra_size)
+{
+ snd_card_t *card;
+ int err;
+
+ if (extra_size < 0)
+ extra_size = 0;
+ card = kcalloc(1, sizeof(*card) + extra_size, GFP_KERNEL);
+ if (card == NULL)
+ return NULL;
+ if (xid) {
+ if (!snd_info_check_reserved_words(xid))
+ goto __error;
+ strlcpy(card->id, xid, sizeof(card->id));
+ }
+ err = 0;
+ write_lock(&snd_card_rwlock);
+ if (idx < 0) {
+ int idx2;
+ for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
+ if (~snd_cards_lock & idx & 1<<idx2) {
+ idx = idx2;
+ if (idx >= snd_ecards_limit)
+ snd_ecards_limit = idx + 1;
+ break;
+ }
+ } else if (idx < snd_ecards_limit) {
+ if (snd_cards_lock & (1 << idx))
+ err = -ENODEV; /* invalid */
+ } else if (idx < SNDRV_CARDS)
+ snd_ecards_limit = idx + 1; /* increase the limit */
+ else
+ err = -ENODEV;
+ if (idx < 0 || err < 0) {
+ write_unlock(&snd_card_rwlock);
+ snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1);
+ goto __error;
+ }
+ snd_cards_lock |= 1 << idx; /* lock it */
+ write_unlock(&snd_card_rwlock);
+ 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_waitqueue_head(&card->shutdown_sleep);
+ INIT_WORK(&card->free_workq, snd_card_free_thread, card);
+#ifdef CONFIG_PM
+ init_MUTEX(&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 */
+ if ((err = snd_ctl_create(card)) < 0) {
+ snd_printd("unable to register control minors\n");
+ goto __error;
+ }
+ if ((err = snd_info_card_create(card)) < 0) {
+ snd_printd("unable to create card info\n");
+ goto __error_ctl;
+ }
+ if (extra_size > 0)
+ card->private_data = (char *)card + sizeof(snd_card_t);
+ return card;
+
+ __error_ctl:
+ snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
+ __error:
+ kfree(card);
+ return NULL;
+}
+
+static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
+{
+ return POLLERR | POLLNVAL;
+}
+
+/**
+ * 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(snd_card_t * card)
+{
+ struct snd_monitor_file *mfile;
+ struct file *file;
+ struct snd_shutdown_f_ops *s_f_ops;
+ struct file_operations *f_ops, *old_f_ops;
+ int err;
+
+ 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 */
+ write_lock(&snd_card_rwlock);
+ snd_cards[card->number] = NULL;
+ write_unlock(&snd_card_rwlock);
+
+ /* phase 2: replace file->f_op with special dummy operations */
+
+ spin_lock(&card->files_lock);
+ mfile = card->files;
+ while (mfile) {
+ file = mfile->file;
+
+ /* it's critical part, use endless loop */
+ /* we have no room to fail */
+ s_f_ops = kmalloc(sizeof(struct snd_shutdown_f_ops), GFP_ATOMIC);
+ if (s_f_ops == NULL)
+ panic("Atomic allocation failed for snd_shutdown_f_ops!");
+
+ f_ops = &s_f_ops->f_ops;
+
+ memset(f_ops, 0, sizeof(*f_ops));
+ f_ops->owner = file->f_op->owner;
+ f_ops->release = file->f_op->release;
+ f_ops->poll = snd_disconnect_poll;
+
+ s_f_ops->next = card->s_f_ops;
+ card->s_f_ops = s_f_ops;
+
+ f_ops = fops_get(f_ops);
+
+ old_f_ops = file->f_op;
+ file->f_op = f_ops; /* must be atomic */
+ fops_put(old_f_ops);
+
+ mfile = mfile->next;
+ }
+ 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);
+
+ return 0;
+}
+
+#if defined(CONFIG_PM) && defined(CONFIG_SND_GENERIC_PM)
+static void snd_generic_device_unregister(struct snd_generic_device *dev);
+#endif
+
+/**
+ * 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.
+ */
+int snd_card_free(snd_card_t * card)
+{
+ struct snd_shutdown_f_ops *s_f_ops;
+
+ if (card == NULL)
+ return -EINVAL;
+ write_lock(&snd_card_rwlock);
+ snd_cards[card->number] = NULL;
+ write_unlock(&snd_card_rwlock);
+
+#ifdef CONFIG_PM
+ wake_up(&card->power_sleep);
+#ifdef CONFIG_SND_GENERIC_PM
+ if (card->pm_dev) {
+ snd_generic_device_unregister(card->pm_dev);
+ card->pm_dev = NULL;
+ }
+#endif
+#endif
+
+ /* wait, until all devices are ready for the free operation */
+ wait_event(card->shutdown_sleep, card->files == NULL);
+
+#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);
+ if (card->proc_id)
+ snd_info_unregister(card->proc_id);
+ if (snd_info_card_free(card) < 0) {
+ snd_printk(KERN_WARNING "unable to free card info\n");
+ /* Not fatal error */
+ }
+ while (card->s_f_ops) {
+ s_f_ops = card->s_f_ops;
+ card->s_f_ops = s_f_ops->next;
+ kfree(s_f_ops);
+ }
+ write_lock(&snd_card_rwlock);
+ snd_cards_lock &= ~(1 << card->number);
+ write_unlock(&snd_card_rwlock);
+ kfree(card);
+ return 0;
+}
+
+static void snd_card_free_thread(void * __card)
+{
+ snd_card_t *card = __card;
+ struct module * module = card->module;
+
+ if (!try_module_get(module)) {
+ snd_printk(KERN_ERR "unable to lock toplevel module for card %i in free thread\n", card->number);
+ module = NULL;
+ }
+
+ snd_card_free(card);
+
+ module_put(module);
+}
+
+/**
+ * snd_card_free_in_thread - call snd_card_free() in thread
+ * @card: soundcard structure
+ *
+ * This function schedules the call of snd_card_free() function in a
+ * work queue. When all devices are released (non-busy), the work
+ * is woken up and calls snd_card_free().
+ *
+ * When a card can be disconnected at any time by hotplug service,
+ * this function should be used in disconnect (or detach) callback
+ * instead of calling snd_card_free() directly.
+ *
+ * Returns - zero otherwise a negative error code if the start of thread failed.
+ */
+int snd_card_free_in_thread(snd_card_t * card)
+{
+ if (card->files == NULL) {
+ snd_card_free(card);
+ return 0;
+ }
+
+ if (schedule_work(&card->free_workq))
+ return 0;
+
+ snd_printk(KERN_ERR "schedule_work() failed in snd_card_free_in_thread for card %i\n", card->number);
+ /* try to free the structure immediately */
+ snd_card_free(card);
+ return -EFAULT;
+}
+
+static void choose_default_id(snd_card_t * card)
+{
+ int i, len, idx_flag = 0, loops = 8;
+ char *id, *spos;
+
+ id = spos = card->shortname;
+ while (*id != '\0') {
+ if (*id == ' ')
+ spos = id + 1;
+ id++;
+ }
+ id = card->id;
+ while (*spos != '\0' && !isalnum(*spos))
+ spos++;
+ if (isdigit(*spos))
+ *id++ = isalpha(card->shortname[0]) ? card->shortname[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 choose default 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)
+ id[len-1]++;
+ 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++;
+ *spos++ = '_';
+ *spos++ = '1';
+ *spos++ = '\0';
+ idx_flag++;
+ }
+ }
+}
+
+/**
+ * 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 registrain failed.
+ */
+int snd_card_register(snd_card_t * card)
+{
+ int err;
+ snd_info_entry_t *entry;
+
+ snd_runtime_check(card != NULL, return -EINVAL);
+ if ((err = snd_device_register_all(card)) < 0)
+ return err;
+ write_lock(&snd_card_rwlock);
+ if (snd_cards[card->number]) {
+ /* already registered */
+ write_unlock(&snd_card_rwlock);
+ return 0;
+ }
+ if (card->id[0] == '\0')
+ choose_default_id(card);
+ snd_cards[card->number] = card;
+ write_unlock(&snd_card_rwlock);
+ if ((err = snd_info_card_register(card)) < 0) {
+ snd_printd("unable to create card info\n");
+ goto __skip_info;
+ }
+ if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
+ snd_printd("unable to create card entry\n");
+ goto __skip_info;
+ }
+ entry->c.text.read_size = PAGE_SIZE;
+ 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;
+ __skip_info:
+#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
+ return 0;
+}
+
+static snd_info_entry_t *snd_card_info_entry = NULL;
+
+static void snd_card_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
+{
+ int idx, count;
+ snd_card_t *card;
+
+ for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
+ read_lock(&snd_card_rwlock);
+ if ((card = snd_cards[idx]) != NULL) {
+ count++;
+ snd_iprintf(buffer, "%i [%-15s]: %s - %s\n",
+ idx,
+ card->id,
+ card->driver,
+ card->shortname);
+ snd_iprintf(buffer, " %s\n",
+ card->longname);
+ }
+ read_unlock(&snd_card_rwlock);
+ }
+ if (!count)
+ snd_iprintf(buffer, "--- no soundcards ---\n");
+}
+
+#if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)
+
+void snd_card_info_read_oss(snd_info_buffer_t * buffer)
+{
+ int idx, count;
+ snd_card_t *card;
+
+ for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
+ read_lock(&snd_card_rwlock);
+ if ((card = snd_cards[idx]) != NULL) {
+ count++;
+ snd_iprintf(buffer, "%s\n", card->longname);
+ }
+ read_unlock(&snd_card_rwlock);
+ }
+ if (!count) {
+ snd_iprintf(buffer, "--- no soundcards ---\n");
+ }
+}
+
+#endif
+
+#ifdef MODULE
+static snd_info_entry_t *snd_card_module_info_entry;
+static void snd_card_module_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
+{
+ int idx;
+ snd_card_t *card;
+
+ for (idx = 0; idx < SNDRV_CARDS; idx++) {
+ read_lock(&snd_card_rwlock);
+ if ((card = snd_cards[idx]) != NULL)
+ snd_iprintf(buffer, "%i %s\n", idx, card->module->name);
+ read_unlock(&snd_card_rwlock);
+ }
+}
+#endif
+
+int __init snd_card_info_init(void)
+{
+ snd_info_entry_t *entry;
+
+ entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
+ snd_runtime_check(entry != NULL, return -ENOMEM);
+ entry->c.text.read_size = PAGE_SIZE;
+ 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_size = PAGE_SIZE;
+ 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)
+{
+ if (snd_card_info_entry)
+ snd_info_unregister(snd_card_info_entry);
+#ifdef MODULE
+ if (snd_card_module_info_entry)
+ snd_info_unregister(snd_card_module_info_entry);
+#endif
+ return 0;
+}
+
+/**
+ * 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(snd_card_t *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;
+}
+
+/**
+ * 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(snd_card_t *card, struct file *file)
+{
+ struct snd_monitor_file *mfile;
+
+ mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
+ if (mfile == NULL)
+ return -ENOMEM;
+ mfile->file = file;
+ mfile->next = NULL;
+ spin_lock(&card->files_lock);
+ if (card->shutdown) {
+ spin_unlock(&card->files_lock);
+ kfree(mfile);
+ return -ENODEV;
+ }
+ mfile->next = card->files;
+ card->files = mfile;
+ spin_unlock(&card->files_lock);
+ return 0;
+}
+
+/**
+ * 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 the release of the card is
+ * scheduled, it will wake up the the thread to call snd_card_free()
+ * (see snd_card_free_in_thread() function).
+ *
+ * Returns zero or a negative error code.
+ */
+int snd_card_file_remove(snd_card_t *card, struct file *file)
+{
+ struct snd_monitor_file *mfile, *pfile = NULL;
+
+ spin_lock(&card->files_lock);
+ mfile = card->files;
+ while (mfile) {
+ if (mfile->file == file) {
+ if (pfile)
+ pfile->next = mfile->next;
+ else
+ card->files = mfile->next;
+ break;
+ }
+ pfile = mfile;
+ mfile = mfile->next;
+ }
+ spin_unlock(&card->files_lock);
+ if (card->files == NULL)
+ wake_up(&card->shutdown_sleep);
+ if (!mfile) {
+ snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
+ return -ENOENT;
+ }
+ kfree(mfile);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+/**
+ * snd_power_wait - wait until the power-state is changed.
+ * @card: soundcard structure
+ * @power_state: expected power state
+ * @file: file structure for the O_NONBLOCK check (optional)
+ *
+ * Waits until the power-state is changed.
+ *
+ * Note: the power lock must be active before call.
+ */
+int snd_power_wait(snd_card_t *card, unsigned int power_state, struct file *file)
+{
+ 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;
+#if 0 /* block all devices */
+ if (file && (file->f_flags & O_NONBLOCK)) {
+ result = -EAGAIN;
+ break;
+ }
+#endif
+ 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;
+}
+
+/**
+ * snd_card_set_pm_callback - set the PCI power-management callbacks
+ * @card: soundcard structure
+ * @suspend: suspend callback function
+ * @resume: resume callback function
+ * @private_data: private data to pass to the callback functions
+ *
+ * Sets the power-management callback functions of the card.
+ * These callbacks are called from ALSA's common PCI suspend/resume
+ * handler and from the control API.
+ */
+int snd_card_set_pm_callback(snd_card_t *card,
+ int (*suspend)(snd_card_t *, pm_message_t),
+ int (*resume)(snd_card_t *),
+ void *private_data)
+{
+ card->pm_suspend = suspend;
+ card->pm_resume = resume;
+ card->pm_private_data = private_data;
+ return 0;
+}
+
+#ifdef CONFIG_SND_GENERIC_PM
+/*
+ * use platform_device for generic power-management without a proper bus
+ * (e.g. ISA)
+ */
+struct snd_generic_device {
+ struct platform_device pdev;
+ snd_card_t *card;
+};
+
+#define get_snd_generic_card(dev) container_of(to_platform_device(dev), struct snd_generic_device, pdev)->card
+
+#define SND_GENERIC_NAME "snd_generic_pm"
+
+static int snd_generic_suspend(struct device *dev, u32 state, u32 level);
+static int snd_generic_resume(struct device *dev, u32 level);
+
+static struct device_driver snd_generic_driver = {
+ .name = SND_GENERIC_NAME,
+ .bus = &platform_bus_type,
+ .suspend = snd_generic_suspend,
+ .resume = snd_generic_resume,
+};
+
+static int generic_driver_registered;
+
+static void generic_driver_unregister(void)
+{
+ if (generic_driver_registered) {
+ generic_driver_registered--;
+ if (! generic_driver_registered)
+ driver_unregister(&snd_generic_driver);
+ }
+}
+
+static struct snd_generic_device *snd_generic_device_register(snd_card_t *card)
+{
+ struct snd_generic_device *dev;
+
+ if (! generic_driver_registered) {
+ if (driver_register(&snd_generic_driver) < 0)
+ return NULL;
+ }
+ generic_driver_registered++;
+
+ dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
+ if (! dev) {
+ generic_driver_unregister();
+ return NULL;
+ }
+
+ dev->pdev.name = SND_GENERIC_NAME;
+ dev->pdev.id = card->number;
+ dev->card = card;
+ if (platform_device_register(&dev->pdev) < 0) {
+ kfree(dev);
+ generic_driver_unregister();
+ return NULL;
+ }
+ return dev;
+}
+
+static void snd_generic_device_unregister(struct snd_generic_device *dev)
+{
+ platform_device_unregister(&dev->pdev);
+ kfree(dev);
+ generic_driver_unregister();
+}
+
+/* suspend/resume callbacks for snd_generic platform device */
+static int snd_generic_suspend(struct device *dev, u32 state, u32 level)
+{
+ snd_card_t *card;
+
+ if (level != SUSPEND_DISABLE)
+ return 0;
+
+ card = get_snd_generic_card(dev);
+ if (card->power_state == SNDRV_CTL_POWER_D3hot)
+ return 0;
+ card->pm_suspend(card, PMSG_SUSPEND);
+ snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
+ return 0;
+}
+
+static int snd_generic_resume(struct device *dev, u32 level)
+{
+ snd_card_t *card;
+
+ if (level != RESUME_ENABLE)
+ return 0;
+
+ card = get_snd_generic_card(dev);
+ if (card->power_state == SNDRV_CTL_POWER_D0)
+ return 0;
+ card->pm_resume(card);
+ snd_power_change_state(card, SNDRV_CTL_POWER_D0);
+ return 0;
+}
+
+/**
+ * snd_card_set_generic_pm_callback - set the generic power-management callbacks
+ * @card: soundcard structure
+ * @suspend: suspend callback function
+ * @resume: resume callback function
+ * @private_data: private data to pass to the callback functions
+ *
+ * Registers the power-management and sets the lowlevel callbacks for
+ * the given card. These callbacks are called from the ALSA's common
+ * PM handler and from the control API.
+ */
+int snd_card_set_generic_pm_callback(snd_card_t *card,
+ int (*suspend)(snd_card_t *, pm_message_t),
+ int (*resume)(snd_card_t *),
+ void *private_data)
+{
+ card->pm_dev = snd_generic_device_register(card);
+ if (! card->pm_dev)
+ return -ENOMEM;
+ snd_card_set_pm_callback(card, suspend, resume, private_data);
+ return 0;
+}
+#endif /* CONFIG_SND_GENERIC_PM */
+
+#ifdef CONFIG_PCI
+int snd_card_pci_suspend(struct pci_dev *dev, pm_message_t state)
+{
+ snd_card_t *card = pci_get_drvdata(dev);
+ int err;
+ if (! card || ! card->pm_suspend)
+ return 0;
+ if (card->power_state == SNDRV_CTL_POWER_D3hot)
+ return 0;
+ err = card->pm_suspend(card, PMSG_SUSPEND);
+ pci_save_state(dev);
+ snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
+ return err;
+}
+
+int snd_card_pci_resume(struct pci_dev *dev)
+{
+ snd_card_t *card = pci_get_drvdata(dev);
+ if (! card || ! card->pm_resume)
+ return 0;
+ if (card->power_state == SNDRV_CTL_POWER_D0)
+ return 0;
+ /* restore the PCI config space */
+ pci_restore_state(dev);
+ card->pm_resume(card);
+ snd_power_change_state(card, SNDRV_CTL_POWER_D0);
+ return 0;
+}
+#endif
+
+#endif /* CONFIG_PM */