1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Initialization routines
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
7 #include <linux/init.h>
8 #include <linux/sched.h>
9 #include <linux/module.h>
10 #include <linux/device.h>
11 #include <linux/file.h>
12 #include <linux/slab.h>
13 #include <linux/time.h>
14 #include <linux/ctype.h>
16 #include <linux/completion.h>
18 #include <sound/core.h>
19 #include <sound/control.h>
20 #include <sound/info.h>
22 /* monitor files for graceful shutdown (hotplug) */
23 struct snd_monitor_file
{
25 const struct file_operations
*disconnected_f_op
;
26 struct list_head shutdown_list
; /* still need to shutdown */
27 struct list_head list
; /* link of monitor files */
30 static DEFINE_SPINLOCK(shutdown_lock
);
31 static LIST_HEAD(shutdown_files
);
33 static const struct file_operations snd_shutdown_f_ops
;
35 /* locked for registering/using */
36 static DECLARE_BITMAP(snd_cards_lock
, SNDRV_CARDS
);
37 static struct snd_card
*snd_cards
[SNDRV_CARDS
];
39 static DEFINE_MUTEX(snd_card_mutex
);
41 static char *slots
[SNDRV_CARDS
];
42 module_param_array(slots
, charp
, NULL
, 0444);
43 MODULE_PARM_DESC(slots
, "Module names assigned to the slots.");
45 /* return non-zero if the given index is reserved for the given
46 * module via slots option
48 static int module_slot_match(struct module
*module
, int idx
)
54 if (!module
|| !*module
->name
|| !slots
[idx
])
60 match
= 0; /* negative match */
63 /* compare module name strings
64 * hyphens are handled as equivalent with underscore
82 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
83 int (*snd_mixer_oss_notify_callback
)(struct snd_card
*card
, int free_flag
);
84 EXPORT_SYMBOL(snd_mixer_oss_notify_callback
);
87 static int check_empty_slot(struct module
*module
, int slot
)
89 return !slots
[slot
] || !*slots
[slot
];
92 /* return an empty slot number (>= 0) found in the given bitmask @mask.
93 * @mask == -1 == 0xffffffff means: take any free slot up to 32
94 * when no slot is available, return the original @mask as is.
96 static int get_slot_from_bitmask(int mask
, int (*check
)(struct module
*, int),
97 struct module
*module
)
101 for (slot
= 0; slot
< SNDRV_CARDS
; slot
++) {
102 if (slot
< 32 && !(mask
& (1U << slot
)))
104 if (!test_bit(slot
, snd_cards_lock
)) {
105 if (check(module
, slot
))
106 return slot
; /* found */
109 return mask
; /* unchanged */
112 /* the default release callback set in snd_device_initialize() below;
113 * this is just NOP for now, as almost all jobs are already done in
114 * dev_free callback of snd_device chain instead.
116 static void default_release(struct device
*dev
)
121 * snd_device_initialize - Initialize struct device for sound devices
122 * @dev: device to initialize
123 * @card: card to assign, optional
125 void snd_device_initialize(struct device
*dev
, struct snd_card
*card
)
127 device_initialize(dev
);
129 dev
->parent
= &card
->card_dev
;
130 dev
->class = sound_class
;
131 dev
->release
= default_release
;
133 EXPORT_SYMBOL_GPL(snd_device_initialize
);
135 static int snd_card_do_free(struct snd_card
*card
);
136 static const struct attribute_group card_dev_attr_group
;
138 static void release_card_device(struct device
*dev
)
140 snd_card_do_free(dev_to_snd_card(dev
));
144 * snd_card_new - create and initialize a soundcard structure
145 * @parent: the parent device object
146 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
147 * @xid: card identification (ASCII string)
148 * @module: top level module for locking
149 * @extra_size: allocate this extra size after the main soundcard structure
150 * @card_ret: the pointer to store the created card instance
152 * Creates and initializes a soundcard structure.
154 * The function allocates snd_card instance via kzalloc with the given
155 * space for the driver to use freely. The allocated struct is stored
156 * in the given card_ret pointer.
158 * Return: Zero if successful or a negative error code.
160 int snd_card_new(struct device
*parent
, int idx
, const char *xid
,
161 struct module
*module
, int extra_size
,
162 struct snd_card
**card_ret
)
164 struct snd_card
*card
;
167 if (snd_BUG_ON(!card_ret
))
173 card
= kzalloc(sizeof(*card
) + extra_size
, GFP_KERNEL
);
177 card
->private_data
= (char *)card
+ sizeof(struct snd_card
);
179 strlcpy(card
->id
, xid
, sizeof(card
->id
));
181 mutex_lock(&snd_card_mutex
);
182 if (idx
< 0) /* first check the matching module-name slot */
183 idx
= get_slot_from_bitmask(idx
, module_slot_match
, module
);
184 if (idx
< 0) /* if not matched, assign an empty slot */
185 idx
= get_slot_from_bitmask(idx
, check_empty_slot
, module
);
188 else if (idx
< snd_ecards_limit
) {
189 if (test_bit(idx
, snd_cards_lock
))
190 err
= -EBUSY
; /* invalid */
191 } else if (idx
>= SNDRV_CARDS
)
194 mutex_unlock(&snd_card_mutex
);
195 dev_err(parent
, "cannot find the slot for index %d (range 0-%i), error: %d\n",
196 idx
, snd_ecards_limit
- 1, err
);
200 set_bit(idx
, snd_cards_lock
); /* lock it */
201 if (idx
>= snd_ecards_limit
)
202 snd_ecards_limit
= idx
+ 1; /* increase the limit */
203 mutex_unlock(&snd_card_mutex
);
206 card
->module
= module
;
207 INIT_LIST_HEAD(&card
->devices
);
208 init_rwsem(&card
->controls_rwsem
);
209 rwlock_init(&card
->ctl_files_rwlock
);
210 INIT_LIST_HEAD(&card
->controls
);
211 INIT_LIST_HEAD(&card
->ctl_files
);
212 spin_lock_init(&card
->files_lock
);
213 INIT_LIST_HEAD(&card
->files_list
);
215 init_waitqueue_head(&card
->power_sleep
);
217 init_waitqueue_head(&card
->remove_sleep
);
219 device_initialize(&card
->card_dev
);
220 card
->card_dev
.parent
= parent
;
221 card
->card_dev
.class = sound_class
;
222 card
->card_dev
.release
= release_card_device
;
223 card
->card_dev
.groups
= card
->dev_groups
;
224 card
->dev_groups
[0] = &card_dev_attr_group
;
225 err
= kobject_set_name(&card
->card_dev
.kobj
, "card%d", idx
);
229 snprintf(card
->irq_descr
, sizeof(card
->irq_descr
), "%s:%s",
230 dev_driver_string(card
->dev
), dev_name(&card
->card_dev
));
232 /* the control interface cannot be accessed from the user space until */
233 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
234 err
= snd_ctl_create(card
);
236 dev_err(parent
, "unable to register control minors\n");
239 err
= snd_info_card_create(card
);
241 dev_err(parent
, "unable to create card info\n");
248 snd_device_free_all(card
);
250 put_device(&card
->card_dev
);
253 EXPORT_SYMBOL(snd_card_new
);
256 * snd_card_ref - Get the card object from the index
257 * @idx: the card index
259 * Returns a card object corresponding to the given index or NULL if not found.
260 * Release the object via snd_card_unref().
262 struct snd_card
*snd_card_ref(int idx
)
264 struct snd_card
*card
;
266 mutex_lock(&snd_card_mutex
);
267 card
= snd_cards
[idx
];
269 get_device(&card
->card_dev
);
270 mutex_unlock(&snd_card_mutex
);
273 EXPORT_SYMBOL_GPL(snd_card_ref
);
275 /* return non-zero if a card is already locked */
276 int snd_card_locked(int card
)
280 mutex_lock(&snd_card_mutex
);
281 locked
= test_bit(card
, snd_cards_lock
);
282 mutex_unlock(&snd_card_mutex
);
286 static loff_t
snd_disconnect_llseek(struct file
*file
, loff_t offset
, int orig
)
291 static ssize_t
snd_disconnect_read(struct file
*file
, char __user
*buf
,
292 size_t count
, loff_t
*offset
)
297 static ssize_t
snd_disconnect_write(struct file
*file
, const char __user
*buf
,
298 size_t count
, loff_t
*offset
)
303 static int snd_disconnect_release(struct inode
*inode
, struct file
*file
)
305 struct snd_monitor_file
*df
= NULL
, *_df
;
307 spin_lock(&shutdown_lock
);
308 list_for_each_entry(_df
, &shutdown_files
, shutdown_list
) {
309 if (_df
->file
== file
) {
311 list_del_init(&df
->shutdown_list
);
315 spin_unlock(&shutdown_lock
);
318 if ((file
->f_flags
& FASYNC
) && df
->disconnected_f_op
->fasync
)
319 df
->disconnected_f_op
->fasync(-1, file
, 0);
320 return df
->disconnected_f_op
->release(inode
, file
);
323 panic("%s(%p, %p) failed!", __func__
, inode
, file
);
326 static __poll_t
snd_disconnect_poll(struct file
* file
, poll_table
* wait
)
328 return EPOLLERR
| EPOLLNVAL
;
331 static long snd_disconnect_ioctl(struct file
*file
,
332 unsigned int cmd
, unsigned long arg
)
337 static int snd_disconnect_mmap(struct file
*file
, struct vm_area_struct
*vma
)
342 static int snd_disconnect_fasync(int fd
, struct file
*file
, int on
)
347 static const struct file_operations snd_shutdown_f_ops
=
349 .owner
= THIS_MODULE
,
350 .llseek
= snd_disconnect_llseek
,
351 .read
= snd_disconnect_read
,
352 .write
= snd_disconnect_write
,
353 .release
= snd_disconnect_release
,
354 .poll
= snd_disconnect_poll
,
355 .unlocked_ioctl
= snd_disconnect_ioctl
,
357 .compat_ioctl
= snd_disconnect_ioctl
,
359 .mmap
= snd_disconnect_mmap
,
360 .fasync
= snd_disconnect_fasync
364 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
365 * @card: soundcard structure
367 * Disconnects all APIs from the file-operations (user space).
369 * Return: Zero, otherwise a negative error code.
371 * Note: The current implementation replaces all active file->f_op with special
372 * dummy file operations (they do nothing except release).
374 int snd_card_disconnect(struct snd_card
*card
)
376 struct snd_monitor_file
*mfile
;
381 spin_lock(&card
->files_lock
);
382 if (card
->shutdown
) {
383 spin_unlock(&card
->files_lock
);
388 /* replace file->f_op with special dummy operations */
389 list_for_each_entry(mfile
, &card
->files_list
, list
) {
390 /* it's critical part, use endless loop */
391 /* we have no room to fail */
392 mfile
->disconnected_f_op
= mfile
->file
->f_op
;
394 spin_lock(&shutdown_lock
);
395 list_add(&mfile
->shutdown_list
, &shutdown_files
);
396 spin_unlock(&shutdown_lock
);
398 mfile
->file
->f_op
= &snd_shutdown_f_ops
;
399 fops_get(mfile
->file
->f_op
);
401 spin_unlock(&card
->files_lock
);
403 /* notify all connected devices about disconnection */
404 /* at this point, they cannot respond to any calls except release() */
406 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
407 if (snd_mixer_oss_notify_callback
)
408 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_DISCONNECT
);
411 /* notify all devices that we are disconnected */
412 snd_device_disconnect_all(card
);
414 snd_info_card_disconnect(card
);
415 if (card
->registered
) {
416 device_del(&card
->card_dev
);
417 card
->registered
= false;
420 /* disable fops (user space) operations for ALSA API */
421 mutex_lock(&snd_card_mutex
);
422 snd_cards
[card
->number
] = NULL
;
423 clear_bit(card
->number
, snd_cards_lock
);
424 mutex_unlock(&snd_card_mutex
);
427 wake_up(&card
->power_sleep
);
431 EXPORT_SYMBOL(snd_card_disconnect
);
434 * snd_card_disconnect_sync - disconnect card and wait until files get closed
435 * @card: card object to disconnect
437 * This calls snd_card_disconnect() for disconnecting all belonging components
438 * and waits until all pending files get closed.
439 * It assures that all accesses from user-space finished so that the driver
440 * can release its resources gracefully.
442 void snd_card_disconnect_sync(struct snd_card
*card
)
446 err
= snd_card_disconnect(card
);
449 "snd_card_disconnect error (%d), skipping sync\n",
454 spin_lock_irq(&card
->files_lock
);
455 wait_event_lock_irq(card
->remove_sleep
,
456 list_empty(&card
->files_list
),
458 spin_unlock_irq(&card
->files_lock
);
460 EXPORT_SYMBOL_GPL(snd_card_disconnect_sync
);
462 static int snd_card_do_free(struct snd_card
*card
)
464 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
465 if (snd_mixer_oss_notify_callback
)
466 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_FREE
);
468 snd_device_free_all(card
);
469 if (card
->private_free
)
470 card
->private_free(card
);
471 if (snd_info_card_free(card
) < 0) {
472 dev_warn(card
->dev
, "unable to free card info\n");
473 /* Not fatal error */
475 if (card
->release_completion
)
476 complete(card
->release_completion
);
482 * snd_card_free_when_closed - Disconnect the card, free it later eventually
483 * @card: soundcard structure
485 * Unlike snd_card_free(), this function doesn't try to release the card
486 * resource immediately, but tries to disconnect at first. When the card
487 * is still in use, the function returns before freeing the resources.
488 * The card resources will be freed when the refcount gets to zero.
490 int snd_card_free_when_closed(struct snd_card
*card
)
492 int ret
= snd_card_disconnect(card
);
495 put_device(&card
->card_dev
);
498 EXPORT_SYMBOL(snd_card_free_when_closed
);
501 * snd_card_free - frees given soundcard structure
502 * @card: soundcard structure
504 * This function releases the soundcard structure and the all assigned
505 * devices automatically. That is, you don't have to release the devices
508 * This function waits until the all resources are properly released.
510 * Return: Zero. Frees all associated devices and frees the control
511 * interface associated to given soundcard.
513 int snd_card_free(struct snd_card
*card
)
515 struct completion released
;
518 init_completion(&released
);
519 card
->release_completion
= &released
;
520 ret
= snd_card_free_when_closed(card
);
523 /* wait, until all devices are ready for the free operation */
524 wait_for_completion(&released
);
527 EXPORT_SYMBOL(snd_card_free
);
529 /* retrieve the last word of shortname or longname */
530 static const char *retrieve_id_from_card_name(const char *name
)
532 const char *spos
= name
;
535 if (isspace(*name
) && isalnum(name
[1]))
542 /* return true if the given id string doesn't conflict any other card ids */
543 static bool card_id_ok(struct snd_card
*card
, const char *id
)
546 if (!snd_info_check_reserved_words(id
))
548 for (i
= 0; i
< snd_ecards_limit
; i
++) {
549 if (snd_cards
[i
] && snd_cards
[i
] != card
&&
550 !strcmp(snd_cards
[i
]->id
, id
))
556 /* copy to card->id only with valid letters from nid */
557 static void copy_valid_id_string(struct snd_card
*card
, const char *src
,
562 while (*nid
&& !isalnum(*nid
))
565 *id
++ = isalpha(*src
) ? *src
: 'D';
566 while (*nid
&& (size_t)(id
- card
->id
) < sizeof(card
->id
) - 1) {
574 /* Set card->id from the given string
575 * If the string conflicts with other ids, add a suffix to make it unique.
577 static void snd_card_set_id_no_lock(struct snd_card
*card
, const char *src
,
581 bool is_default
= false;
584 copy_valid_id_string(card
, src
, nid
);
588 /* use "Default" for obviously invalid strings
589 * ("card" conflicts with proc directories)
591 if (!*id
|| !strncmp(id
, "card", 4)) {
592 strcpy(id
, "Default");
597 for (loops
= 0; loops
< SNDRV_CARDS
; loops
++) {
599 char sfxstr
[5]; /* "_012" */
602 if (card_id_ok(card
, id
))
605 /* Add _XYZ suffix */
606 sprintf(sfxstr
, "_%X", loops
+ 1);
607 sfxlen
= strlen(sfxstr
);
608 if (len
+ sfxlen
>= sizeof(card
->id
))
609 spos
= id
+ sizeof(card
->id
) - sfxlen
- 1;
612 strcpy(spos
, sfxstr
);
614 /* fallback to the default id */
620 dev_err(card
->dev
, "unable to set card id (%s)\n", id
);
621 if (card
->proc_root
->name
)
622 strlcpy(card
->id
, card
->proc_root
->name
, sizeof(card
->id
));
626 * snd_card_set_id - set card identification name
627 * @card: soundcard structure
628 * @nid: new identification string
630 * This function sets the card identification and checks for name
633 void snd_card_set_id(struct snd_card
*card
, const char *nid
)
635 /* check if user specified own card->id */
636 if (card
->id
[0] != '\0')
638 mutex_lock(&snd_card_mutex
);
639 snd_card_set_id_no_lock(card
, nid
, nid
);
640 mutex_unlock(&snd_card_mutex
);
642 EXPORT_SYMBOL(snd_card_set_id
);
645 card_id_show_attr(struct device
*dev
,
646 struct device_attribute
*attr
, char *buf
)
648 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
649 return scnprintf(buf
, PAGE_SIZE
, "%s\n", card
->id
);
653 card_id_store_attr(struct device
*dev
, struct device_attribute
*attr
,
654 const char *buf
, size_t count
)
656 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
657 char buf1
[sizeof(card
->id
)];
658 size_t copy
= count
> sizeof(card
->id
) - 1 ?
659 sizeof(card
->id
) - 1 : count
;
663 for (idx
= 0; idx
< copy
; idx
++) {
665 if (!isalnum(c
) && c
!= '_' && c
!= '-')
668 memcpy(buf1
, buf
, copy
);
670 mutex_lock(&snd_card_mutex
);
671 if (!card_id_ok(NULL
, buf1
)) {
672 mutex_unlock(&snd_card_mutex
);
675 strcpy(card
->id
, buf1
);
676 snd_info_card_id_change(card
);
677 mutex_unlock(&snd_card_mutex
);
682 static DEVICE_ATTR(id
, 0644, card_id_show_attr
, card_id_store_attr
);
685 card_number_show_attr(struct device
*dev
,
686 struct device_attribute
*attr
, char *buf
)
688 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
689 return scnprintf(buf
, PAGE_SIZE
, "%i\n", card
->number
);
692 static DEVICE_ATTR(number
, 0444, card_number_show_attr
, NULL
);
694 static struct attribute
*card_dev_attrs
[] = {
696 &dev_attr_number
.attr
,
700 static const struct attribute_group card_dev_attr_group
= {
701 .attrs
= card_dev_attrs
,
705 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
706 * @card: card instance
707 * @group: attribute group to append
709 int snd_card_add_dev_attr(struct snd_card
*card
,
710 const struct attribute_group
*group
)
714 /* loop for (arraysize-1) here to keep NULL at the last entry */
715 for (i
= 0; i
< ARRAY_SIZE(card
->dev_groups
) - 1; i
++) {
716 if (!card
->dev_groups
[i
]) {
717 card
->dev_groups
[i
] = group
;
722 dev_err(card
->dev
, "Too many groups assigned\n");
725 EXPORT_SYMBOL_GPL(snd_card_add_dev_attr
);
728 * snd_card_register - register the soundcard
729 * @card: soundcard structure
731 * This function registers all the devices assigned to the soundcard.
732 * Until calling this, the ALSA control interface is blocked from the
733 * external accesses. Thus, you should call this function at the end
734 * of the initialization of the card.
736 * Return: Zero otherwise a negative error code if the registration failed.
738 int snd_card_register(struct snd_card
*card
)
742 if (snd_BUG_ON(!card
))
745 if (!card
->registered
) {
746 err
= device_add(&card
->card_dev
);
749 card
->registered
= true;
752 if ((err
= snd_device_register_all(card
)) < 0)
754 mutex_lock(&snd_card_mutex
);
755 if (snd_cards
[card
->number
]) {
756 /* already registered */
757 mutex_unlock(&snd_card_mutex
);
758 return snd_info_card_register(card
); /* register pending info */
761 /* make a unique id name from the given string */
762 char tmpid
[sizeof(card
->id
)];
763 memcpy(tmpid
, card
->id
, sizeof(card
->id
));
764 snd_card_set_id_no_lock(card
, tmpid
, tmpid
);
766 /* create an id from either shortname or longname */
768 src
= *card
->shortname
? card
->shortname
: card
->longname
;
769 snd_card_set_id_no_lock(card
, src
,
770 retrieve_id_from_card_name(src
));
772 snd_cards
[card
->number
] = card
;
773 mutex_unlock(&snd_card_mutex
);
774 err
= snd_info_card_register(card
);
778 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
779 if (snd_mixer_oss_notify_callback
)
780 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_REGISTER
);
784 EXPORT_SYMBOL(snd_card_register
);
786 #ifdef CONFIG_SND_PROC_FS
787 static void snd_card_info_read(struct snd_info_entry
*entry
,
788 struct snd_info_buffer
*buffer
)
791 struct snd_card
*card
;
793 for (idx
= count
= 0; idx
< SNDRV_CARDS
; idx
++) {
794 mutex_lock(&snd_card_mutex
);
795 if ((card
= snd_cards
[idx
]) != NULL
) {
797 snd_iprintf(buffer
, "%2i [%-15s]: %s - %s\n",
802 snd_iprintf(buffer
, " %s\n",
805 mutex_unlock(&snd_card_mutex
);
808 snd_iprintf(buffer
, "--- no soundcards ---\n");
811 #ifdef CONFIG_SND_OSSEMUL
812 void snd_card_info_read_oss(struct snd_info_buffer
*buffer
)
815 struct snd_card
*card
;
817 for (idx
= count
= 0; idx
< SNDRV_CARDS
; idx
++) {
818 mutex_lock(&snd_card_mutex
);
819 if ((card
= snd_cards
[idx
]) != NULL
) {
821 snd_iprintf(buffer
, "%s\n", card
->longname
);
823 mutex_unlock(&snd_card_mutex
);
826 snd_iprintf(buffer
, "--- no soundcards ---\n");
833 static void snd_card_module_info_read(struct snd_info_entry
*entry
,
834 struct snd_info_buffer
*buffer
)
837 struct snd_card
*card
;
839 for (idx
= 0; idx
< SNDRV_CARDS
; idx
++) {
840 mutex_lock(&snd_card_mutex
);
841 if ((card
= snd_cards
[idx
]) != NULL
)
842 snd_iprintf(buffer
, "%2i %s\n",
843 idx
, card
->module
->name
);
844 mutex_unlock(&snd_card_mutex
);
849 int __init
snd_card_info_init(void)
851 struct snd_info_entry
*entry
;
853 entry
= snd_info_create_module_entry(THIS_MODULE
, "cards", NULL
);
856 entry
->c
.text
.read
= snd_card_info_read
;
857 if (snd_info_register(entry
) < 0)
858 return -ENOMEM
; /* freed in error path */
861 entry
= snd_info_create_module_entry(THIS_MODULE
, "modules", NULL
);
864 entry
->c
.text
.read
= snd_card_module_info_read
;
865 if (snd_info_register(entry
) < 0)
866 return -ENOMEM
; /* freed in error path */
871 #endif /* CONFIG_SND_PROC_FS */
874 * snd_component_add - add a component string
875 * @card: soundcard structure
876 * @component: the component id string
878 * This function adds the component id string to the supported list.
879 * The component can be referred from the alsa-lib.
881 * Return: Zero otherwise a negative error code.
884 int snd_component_add(struct snd_card
*card
, const char *component
)
887 int len
= strlen(component
);
889 ptr
= strstr(card
->components
, component
);
891 if (ptr
[len
] == '\0' || ptr
[len
] == ' ') /* already there */
894 if (strlen(card
->components
) + 1 + len
+ 1 > sizeof(card
->components
)) {
898 if (card
->components
[0] != '\0')
899 strcat(card
->components
, " ");
900 strcat(card
->components
, component
);
903 EXPORT_SYMBOL(snd_component_add
);
906 * snd_card_file_add - add the file to the file list of the card
907 * @card: soundcard structure
908 * @file: file pointer
910 * This function adds the file to the file linked-list of the card.
911 * This linked-list is used to keep tracking the connection state,
912 * and to avoid the release of busy resources by hotplug.
914 * Return: zero or a negative error code.
916 int snd_card_file_add(struct snd_card
*card
, struct file
*file
)
918 struct snd_monitor_file
*mfile
;
920 mfile
= kmalloc(sizeof(*mfile
), GFP_KERNEL
);
924 mfile
->disconnected_f_op
= NULL
;
925 INIT_LIST_HEAD(&mfile
->shutdown_list
);
926 spin_lock(&card
->files_lock
);
927 if (card
->shutdown
) {
928 spin_unlock(&card
->files_lock
);
932 list_add(&mfile
->list
, &card
->files_list
);
933 get_device(&card
->card_dev
);
934 spin_unlock(&card
->files_lock
);
937 EXPORT_SYMBOL(snd_card_file_add
);
940 * snd_card_file_remove - remove the file from the file list
941 * @card: soundcard structure
942 * @file: file pointer
944 * This function removes the file formerly added to the card via
945 * snd_card_file_add() function.
946 * If all files are removed and snd_card_free_when_closed() was
947 * called beforehand, it processes the pending release of
950 * Return: Zero or a negative error code.
952 int snd_card_file_remove(struct snd_card
*card
, struct file
*file
)
954 struct snd_monitor_file
*mfile
, *found
= NULL
;
956 spin_lock(&card
->files_lock
);
957 list_for_each_entry(mfile
, &card
->files_list
, list
) {
958 if (mfile
->file
== file
) {
959 list_del(&mfile
->list
);
960 spin_lock(&shutdown_lock
);
961 list_del(&mfile
->shutdown_list
);
962 spin_unlock(&shutdown_lock
);
963 if (mfile
->disconnected_f_op
)
964 fops_put(mfile
->disconnected_f_op
);
969 if (list_empty(&card
->files_list
))
970 wake_up_all(&card
->remove_sleep
);
971 spin_unlock(&card
->files_lock
);
973 dev_err(card
->dev
, "card file remove problem (%p)\n", file
);
977 put_device(&card
->card_dev
);
980 EXPORT_SYMBOL(snd_card_file_remove
);
984 * snd_power_wait - wait until the power-state is changed.
985 * @card: soundcard structure
986 * @power_state: expected power state
988 * Waits until the power-state is changed.
990 * Return: Zero if successful, or a negative error code.
992 int snd_power_wait(struct snd_card
*card
, unsigned int power_state
)
994 wait_queue_entry_t wait
;
998 if (snd_power_get_state(card
) == power_state
)
1000 init_waitqueue_entry(&wait
, current
);
1001 add_wait_queue(&card
->power_sleep
, &wait
);
1003 if (card
->shutdown
) {
1007 if (snd_power_get_state(card
) == power_state
)
1009 set_current_state(TASK_UNINTERRUPTIBLE
);
1010 schedule_timeout(30 * HZ
);
1012 remove_wait_queue(&card
->power_sleep
, &wait
);
1015 EXPORT_SYMBOL(snd_power_wait
);
1016 #endif /* CONFIG_PM */