linux/sound/core/init.c
Linus Torvalds 250f6715a4 The following text was taken from the original review request:
"[RFC PATCH 0/2] audit of linux/device.h users in include/*"
 		https://lkml.org/lkml/2012/3/4/159
 --
 
 Nearly every subsystem has some kind of header with a proto like:
 
 	void foo(struct device *dev);
 
 and yet there is no reason for most of these guys to care about the
 sub fields within the device struct.  This allows us to significantly
 reduce the scope of headers including headers.  For this instance, a
 reduction of about 40% is achieved by replacing the include with the
 simple fact that the device is some kind of a struct.
 
 Unlike the much larger module.h cleanup, this one is simply two
 commits.  One to fix the implicit <linux/device.h> users, and then
 one to delete the device.h includes from the linux/include/ dir
 wherever possible.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJPbNxLAAoJEOvOhAQsB9HWR6QQAMRUZ94O2069/nW9h4TO/xTr
 Hq/80lo/TBBiRmob3iWBP76lzgeeMPPVEX1I6N7YYlhL3IL7HsaJH1DvpIPPHXQP
 GFKcBsZ5ZLV8c4CBDSr+/HFNdhXc0bw0awBjBvR7gAsWuZpNFn4WbhizJi4vWAoE
 4ydhPu55G1G8TkBtYLJQ8xavxsmiNBSDhd2i+0vn6EVpgmXynjOMG8qXyaS97Jvg
 pZLwnN5Wu21coj6+xH3QUKCl1mJ+KGyamWX5gFBVIfsDB3k5H4neijVm7t1en4b0
 cWxmXeR/JE3VLEl/17yN2dodD8qw1QzmTWzz1vmwJl2zK+rRRAByBrL0DP7QCwCZ
 ppeJbdhkMBwqjtknwrmMwsuAzUdJd79GXA+6Vm+xSEkr6FEPK1M0kGbvaqV9Usgd
 ohMewewbO6ddgR9eF7Kw2FAwo0hwkPNEplXIym9rZzFG1h+T0STGSHvkn7LV765E
 ul1FapSV3GCxEVRwWTwD28FLU2+0zlkOZ5sxXwNPTT96cNmW+R7TGuslZKNaMNjX
 q7eBZxo8DtVt/jqJTntR8bs8052c8g1Ac1IKmlW8VSmFwT1M6VBGRn1/JWAhuUgv
 dBK/FF+I1GJTAJWIhaFcKXLHvmV9uhS6JaIhLMDOetoOkpqSptJ42hDG+89WkFRk
 o55GQ5TFdoOpqxVzGbvE
 =3j4+
 -----END PGP SIGNATURE-----

Merge tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull <linux/device.h> avoidance patches from Paul Gortmaker:
 "Nearly every subsystem has some kind of header with a proto like:

	void foo(struct device *dev);

  and yet there is no reason for most of these guys to care about the
  sub fields within the device struct.  This allows us to significantly
  reduce the scope of headers including headers.  For this instance, a
  reduction of about 40% is achieved by replacing the include with the
  simple fact that the device is some kind of a struct.

  Unlike the much larger module.h cleanup, this one is simply two
  commits.  One to fix the implicit <linux/device.h> users, and then one
  to delete the device.h includes from the linux/include/ dir wherever
  possible."

* tag 'device-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  device.h: audit and cleanup users in main include dir
  device.h: cleanup users outside of linux/include (C files)
2012-03-24 10:41:37 -07:00

982 lines
25 KiB
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/module.h>
#include <linux/device.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);
/* retrieve the last word of shortname or longname */
static const char *retrieve_id_from_card_name(const char *name)
{
const char *spos = name;
while (*name) {
if (isspace(*name) && isalnum(name[1]))
spos = name + 1;
name++;
}
return spos;
}
/* return true if the given id string doesn't conflict any other card ids */
static bool card_id_ok(struct snd_card *card, const char *id)
{
int i;
if (!snd_info_check_reserved_words(id))
return false;
for (i = 0; i < snd_ecards_limit; i++) {
if (snd_cards[i] && snd_cards[i] != card &&
!strcmp(snd_cards[i]->id, id))
return false;
}
return true;
}
/* copy to card->id only with valid letters from nid */
static void copy_valid_id_string(struct snd_card *card, const char *src,
const char *nid)
{
char *id = card->id;
while (*nid && !isalnum(*nid))
nid++;
if (isdigit(*nid))
*id++ = isalpha(*src) ? *src : 'D';
while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
if (isalnum(*nid))
*id++ = *nid;
nid++;
}
*id = 0;
}
/* Set card->id from the given string
* If the string conflicts with other ids, add a suffix to make it unique.
*/
static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
const char *nid)
{
int len, loops;
bool with_suffix;
bool is_default = false;
char *id;
copy_valid_id_string(card, src, nid);
id = card->id;
again:
/* use "Default" for obviously invalid strings
* ("card" conflicts with proc directories)
*/
if (!*id || !strncmp(id, "card", 4)) {
strcpy(id, "Default");
is_default = true;
}
with_suffix = false;
for (loops = 0; loops < SNDRV_CARDS; loops++) {
if (card_id_ok(card, id))
return; /* OK */
len = strlen(id);
if (!with_suffix) {
/* add the "_X" suffix */
char *spos = id + len;
if (len > sizeof(card->id) - 3)
spos = id + sizeof(card->id) - 3;
strcpy(spos, "_1");
with_suffix = true;
} else {
/* modify the existing suffix */
if (id[len - 1] != '9')
id[len - 1]++;
else
id[len - 1] = 'A';
}
}
/* fallback to the default id */
if (!is_default) {
*id = 0;
goto again;
}
/* last resort... */
snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
if (card->proc_root->name)
strcpy(card->id, card->proc_root->name);
}
/**
* 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, 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 (!card_id_ok(NULL, buf1)) {
mutex_unlock(&snd_card_mutex);
return -EEXIST;
}
strcpy(card->id, buf1);
snd_info_card_id_change(card);
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;
}
if (*card->id) {
/* make a unique id name from the given string */
char tmpid[sizeof(card->id)];
memcpy(tmpid, card->id, sizeof(card->id));
snd_card_set_id_no_lock(card, tmpid, tmpid);
} else {
/* create an id from either shortname or longname */
const char *src;
src = *card->shortname ? card->shortname : card->longname;
snd_card_set_id_no_lock(card, src,
retrieve_id_from_card_name(src));
}
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 */