init.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 811 行 · 第 1/2 页

				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;
	snd_cards_count++;
	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) {
		kfree(mfile);
	} else {
		snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
		return -ENOENT;
	}
	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 *, unsigned int),
			     int (*resume)(snd_card_t *, unsigned int),
			     void *private_data)
{
	card->pm_suspend = suspend;
	card->pm_resume = resume;
	card->pm_private_data = private_data;
	return 0;
}

static int snd_generic_pm_callback(struct pm_dev *dev, pm_request_t rqst, void *data)
{
	snd_card_t *card = dev->data;

	switch (rqst) {
	case PM_SUSPEND:
		/* FIXME: the correct state value? */
		card->pm_suspend(card, 0);
		break;
	case PM_RESUME:
		/* FIXME: the correct state value? */
		card->pm_resume(card, 0);
		break;
	}
	return 0;
}

/**
 * snd_card_set_dev_pm_callback - set the generic power-management callbacks
 * @card: soundcard structure
 * @type: PM device type (PM_XXX)
 * @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 with the given PM type.  These callbacks are called
 * from the ALSA's common PM handler and from the control API.
 */
int snd_card_set_dev_pm_callback(snd_card_t *card, int type,
				 int (*suspend)(snd_card_t *, unsigned int),
				 int (*resume)(snd_card_t *, unsigned int),
				 void *private_data)
{
	card->pm_dev = pm_register(type, 0, snd_generic_pm_callback);
	if (! card->pm_dev)
		return -ENOMEM;
	card->pm_dev->data = card;
	snd_card_set_pm_callback(card, suspend, resume, private_data);
	return 0;
}

#ifdef CONFIG_PCI
int snd_card_pci_suspend(struct pci_dev *dev, u32 state)
{
	snd_card_t *card = pci_get_drvdata(dev);
	if (! card || ! card->pm_suspend)
		return 0;
	if (card->power_state == SNDRV_CTL_POWER_D3hot)
		return 0;
	/* FIXME: correct state value? */
	return card->pm_suspend(card, 0);
}

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, dev->saved_config_space);
	/* FIXME: correct state value? */
	return card->pm_resume(card, 0);
}
#endif

#endif /* CONFIG_PM */