path: root/sound/core/init.c

/*
 *  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>

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_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 structure. Creates the ALSA control interface
 *  (which is blocked until snd_card_register function is called).
 */
struct snd_card *snd_card_new(int idx, const char *xid,
			 struct module *module, int extra_size)
{
	struct snd_card *card;
	int err, idx2;

	if (extra_size < 0)
		extra_size = 0;
	card = kzalloc(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;
	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;
				}
			}
	}