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/debugfs.h>
17 #include <linux/completion.h>
18 #include <linux/interrupt.h>
20 #include <sound/core.h>
21 #include <sound/control.h>
22 #include <sound/info.h>
24 /* monitor files for graceful shutdown (hotplug) */
25 struct snd_monitor_file
{
27 const struct file_operations
*disconnected_f_op
;
28 struct list_head shutdown_list
; /* still need to shutdown */
29 struct list_head list
; /* link of monitor files */
32 static DEFINE_SPINLOCK(shutdown_lock
);
33 static LIST_HEAD(shutdown_files
);
35 static const struct file_operations snd_shutdown_f_ops
;
37 /* locked for registering/using */
38 static DECLARE_BITMAP(snd_cards_lock
, SNDRV_CARDS
);
39 static struct snd_card
*snd_cards
[SNDRV_CARDS
];
41 static DEFINE_MUTEX(snd_card_mutex
);
43 static char *slots
[SNDRV_CARDS
];
44 module_param_array(slots
, charp
, NULL
, 0444);
45 MODULE_PARM_DESC(slots
, "Module names assigned to the slots.");
47 /* return non-zero if the given index is reserved for the given
48 * module via slots option
50 static int module_slot_match(struct module
*module
, int idx
)
56 if (!module
|| !*module
->name
|| !slots
[idx
])
62 match
= 0; /* negative match */
65 /* compare module name strings
66 * hyphens are handled as equivalent with underscore
84 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
85 int (*snd_mixer_oss_notify_callback
)(struct snd_card
*card
, int free_flag
);
86 EXPORT_SYMBOL(snd_mixer_oss_notify_callback
);
89 static int check_empty_slot(struct module
*module
, int slot
)
91 return !slots
[slot
] || !*slots
[slot
];
94 /* return an empty slot number (>= 0) found in the given bitmask @mask.
95 * @mask == -1 == 0xffffffff means: take any free slot up to 32
96 * when no slot is available, return the original @mask as is.
98 static int get_slot_from_bitmask(int mask
, int (*check
)(struct module
*, int),
99 struct module
*module
)
103 for (slot
= 0; slot
< SNDRV_CARDS
; slot
++) {
104 if (slot
< 32 && !(mask
& (1U << slot
)))
106 if (!test_bit(slot
, snd_cards_lock
)) {
107 if (check(module
, slot
))
108 return slot
; /* found */
111 return mask
; /* unchanged */
114 /* the default release callback set in snd_device_initialize() below;
115 * this is just NOP for now, as almost all jobs are already done in
116 * dev_free callback of snd_device chain instead.
118 static void default_release(struct device
*dev
)
123 * snd_device_initialize - Initialize struct device for sound devices
124 * @dev: device to initialize
125 * @card: card to assign, optional
127 void snd_device_initialize(struct device
*dev
, struct snd_card
*card
)
129 device_initialize(dev
);
131 dev
->parent
= &card
->card_dev
;
132 dev
->class = sound_class
;
133 dev
->release
= default_release
;
135 EXPORT_SYMBOL_GPL(snd_device_initialize
);
137 static int snd_card_init(struct snd_card
*card
, struct device
*parent
,
138 int idx
, const char *xid
, struct module
*module
,
140 static int snd_card_do_free(struct snd_card
*card
);
141 static const struct attribute_group card_dev_attr_group
;
143 static void release_card_device(struct device
*dev
)
145 snd_card_do_free(dev_to_snd_card(dev
));
149 * snd_card_new - create and initialize a soundcard structure
150 * @parent: the parent device object
151 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
152 * @xid: card identification (ASCII string)
153 * @module: top level module for locking
154 * @extra_size: allocate this extra size after the main soundcard structure
155 * @card_ret: the pointer to store the created card instance
157 * The function allocates snd_card instance via kzalloc with the given
158 * space for the driver to use freely. The allocated struct is stored
159 * in the given card_ret pointer.
161 * Return: Zero if successful or a negative error code.
163 int snd_card_new(struct device
*parent
, int idx
, const char *xid
,
164 struct module
*module
, int extra_size
,
165 struct snd_card
**card_ret
)
167 struct snd_card
*card
;
170 if (snd_BUG_ON(!card_ret
))
176 card
= kzalloc(sizeof(*card
) + extra_size
, GFP_KERNEL
);
180 err
= snd_card_init(card
, parent
, idx
, xid
, module
, extra_size
);
182 return err
; /* card is freed by error handler */
187 EXPORT_SYMBOL(snd_card_new
);
189 static void __snd_card_release(struct device
*dev
, void *data
)
195 * snd_devm_card_new - managed snd_card object creation
196 * @parent: the parent device object
197 * @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
198 * @xid: card identification (ASCII string)
199 * @module: top level module for locking
200 * @extra_size: allocate this extra size after the main soundcard structure
201 * @card_ret: the pointer to store the created card instance
203 * This function works like snd_card_new() but manages the allocated resource
204 * via devres, i.e. you don't need to free explicitly.
206 * When a snd_card object is created with this function and registered via
207 * snd_card_register(), the very first devres action to call snd_card_free()
208 * is added automatically. In that way, the resource disconnection is assured
209 * at first, then released in the expected order.
211 * If an error happens at the probe before snd_card_register() is called and
212 * there have been other devres resources, you'd need to free the card manually
213 * via snd_card_free() call in the error; otherwise it may lead to UAF due to
214 * devres call orders. You can use snd_card_free_on_error() helper for
215 * handling it more easily.
217 * Return: zero if successful, or a negative error code
219 int snd_devm_card_new(struct device
*parent
, int idx
, const char *xid
,
220 struct module
*module
, size_t extra_size
,
221 struct snd_card
**card_ret
)
223 struct snd_card
*card
;
227 card
= devres_alloc(__snd_card_release
, sizeof(*card
) + extra_size
,
231 card
->managed
= true;
232 err
= snd_card_init(card
, parent
, idx
, xid
, module
, extra_size
);
234 devres_free(card
); /* in managed mode, we need to free manually */
238 devres_add(parent
, card
);
242 EXPORT_SYMBOL_GPL(snd_devm_card_new
);
245 * snd_card_free_on_error - a small helper for handling devm probe errors
246 * @dev: the managed device object
247 * @ret: the return code from the probe callback
249 * This function handles the explicit snd_card_free() call at the error from
250 * the probe callback. It's just a small helper for simplifying the error
251 * handling with the managed devices.
253 * Return: zero if successful, or a negative error code
255 int snd_card_free_on_error(struct device
*dev
, int ret
)
257 struct snd_card
*card
;
261 card
= devres_find(dev
, __snd_card_release
, NULL
, NULL
);
266 EXPORT_SYMBOL_GPL(snd_card_free_on_error
);
268 static int snd_card_init(struct snd_card
*card
, struct device
*parent
,
269 int idx
, const char *xid
, struct module
*module
,
273 #ifdef CONFIG_SND_DEBUG
278 card
->private_data
= (char *)card
+ sizeof(struct snd_card
);
280 strscpy(card
->id
, xid
, sizeof(card
->id
));
282 mutex_lock(&snd_card_mutex
);
283 if (idx
< 0) /* first check the matching module-name slot */
284 idx
= get_slot_from_bitmask(idx
, module_slot_match
, module
);
285 if (idx
< 0) /* if not matched, assign an empty slot */
286 idx
= get_slot_from_bitmask(idx
, check_empty_slot
, module
);
289 else if (idx
< snd_ecards_limit
) {
290 if (test_bit(idx
, snd_cards_lock
))
291 err
= -EBUSY
; /* invalid */
292 } else if (idx
>= SNDRV_CARDS
)
295 mutex_unlock(&snd_card_mutex
);
296 dev_err(parent
, "cannot find the slot for index %d (range 0-%i), error: %d\n",
297 idx
, snd_ecards_limit
- 1, err
);
299 kfree(card
); /* manually free here, as no destructor called */
302 set_bit(idx
, snd_cards_lock
); /* lock it */
303 if (idx
>= snd_ecards_limit
)
304 snd_ecards_limit
= idx
+ 1; /* increase the limit */
305 mutex_unlock(&snd_card_mutex
);
310 card
->module
= module
;
312 INIT_LIST_HEAD(&card
->devices
);
313 init_rwsem(&card
->controls_rwsem
);
314 rwlock_init(&card
->ctl_files_rwlock
);
315 INIT_LIST_HEAD(&card
->controls
);
316 INIT_LIST_HEAD(&card
->ctl_files
);
317 #ifdef CONFIG_SND_CTL_FAST_LOOKUP
318 xa_init(&card
->ctl_numids
);
319 xa_init(&card
->ctl_hash
);
321 spin_lock_init(&card
->files_lock
);
322 INIT_LIST_HEAD(&card
->files_list
);
323 mutex_init(&card
->memory_mutex
);
325 init_waitqueue_head(&card
->power_sleep
);
326 init_waitqueue_head(&card
->power_ref_sleep
);
327 atomic_set(&card
->power_ref
, 0);
329 init_waitqueue_head(&card
->remove_sleep
);
332 device_initialize(&card
->card_dev
);
333 card
->card_dev
.parent
= parent
;
334 card
->card_dev
.class = sound_class
;
335 card
->card_dev
.release
= release_card_device
;
336 card
->card_dev
.groups
= card
->dev_groups
;
337 card
->dev_groups
[0] = &card_dev_attr_group
;
338 err
= kobject_set_name(&card
->card_dev
.kobj
, "card%d", idx
);
342 snprintf(card
->irq_descr
, sizeof(card
->irq_descr
), "%s:%s",
343 dev_driver_string(card
->dev
), dev_name(&card
->card_dev
));
345 /* the control interface cannot be accessed from the user space until */
346 /* snd_cards_bitmask and snd_cards are set with snd_card_register */
347 err
= snd_ctl_create(card
);
349 dev_err(parent
, "unable to register control minors\n");
352 err
= snd_info_card_create(card
);
354 dev_err(parent
, "unable to create card info\n");
358 #ifdef CONFIG_SND_DEBUG
359 sprintf(name
, "card%d", idx
);
360 card
->debugfs_root
= debugfs_create_dir(name
, sound_debugfs_root
);
365 snd_device_free_all(card
);
367 put_device(&card
->card_dev
);
372 * snd_card_ref - Get the card object from the index
373 * @idx: the card index
375 * Returns a card object corresponding to the given index or NULL if not found.
376 * Release the object via snd_card_unref().
378 * Return: a card object or NULL
380 struct snd_card
*snd_card_ref(int idx
)
382 struct snd_card
*card
;
384 mutex_lock(&snd_card_mutex
);
385 card
= snd_cards
[idx
];
387 get_device(&card
->card_dev
);
388 mutex_unlock(&snd_card_mutex
);
391 EXPORT_SYMBOL_GPL(snd_card_ref
);
393 /* return non-zero if a card is already locked */
394 int snd_card_locked(int card
)
398 mutex_lock(&snd_card_mutex
);
399 locked
= test_bit(card
, snd_cards_lock
);
400 mutex_unlock(&snd_card_mutex
);
404 static loff_t
snd_disconnect_llseek(struct file
*file
, loff_t offset
, int orig
)
409 static ssize_t
snd_disconnect_read(struct file
*file
, char __user
*buf
,
410 size_t count
, loff_t
*offset
)
415 static ssize_t
snd_disconnect_write(struct file
*file
, const char __user
*buf
,
416 size_t count
, loff_t
*offset
)
421 static int snd_disconnect_release(struct inode
*inode
, struct file
*file
)
423 struct snd_monitor_file
*df
= NULL
, *_df
;
425 spin_lock(&shutdown_lock
);
426 list_for_each_entry(_df
, &shutdown_files
, shutdown_list
) {
427 if (_df
->file
== file
) {
429 list_del_init(&df
->shutdown_list
);
433 spin_unlock(&shutdown_lock
);
436 if ((file
->f_flags
& FASYNC
) && df
->disconnected_f_op
->fasync
)
437 df
->disconnected_f_op
->fasync(-1, file
, 0);
438 return df
->disconnected_f_op
->release(inode
, file
);
441 panic("%s(%p, %p) failed!", __func__
, inode
, file
);
444 static __poll_t
snd_disconnect_poll(struct file
* file
, poll_table
* wait
)
446 return EPOLLERR
| EPOLLNVAL
;
449 static long snd_disconnect_ioctl(struct file
*file
,
450 unsigned int cmd
, unsigned long arg
)
455 static int snd_disconnect_mmap(struct file
*file
, struct vm_area_struct
*vma
)
460 static int snd_disconnect_fasync(int fd
, struct file
*file
, int on
)
465 static const struct file_operations snd_shutdown_f_ops
=
467 .owner
= THIS_MODULE
,
468 .llseek
= snd_disconnect_llseek
,
469 .read
= snd_disconnect_read
,
470 .write
= snd_disconnect_write
,
471 .release
= snd_disconnect_release
,
472 .poll
= snd_disconnect_poll
,
473 .unlocked_ioctl
= snd_disconnect_ioctl
,
475 .compat_ioctl
= snd_disconnect_ioctl
,
477 .mmap
= snd_disconnect_mmap
,
478 .fasync
= snd_disconnect_fasync
482 * snd_card_disconnect - disconnect all APIs from the file-operations (user space)
483 * @card: soundcard structure
485 * Disconnects all APIs from the file-operations (user space).
487 * Return: Zero, otherwise a negative error code.
489 * Note: The current implementation replaces all active file->f_op with special
490 * dummy file operations (they do nothing except release).
492 int snd_card_disconnect(struct snd_card
*card
)
494 struct snd_monitor_file
*mfile
;
499 spin_lock(&card
->files_lock
);
500 if (card
->shutdown
) {
501 spin_unlock(&card
->files_lock
);
506 /* replace file->f_op with special dummy operations */
507 list_for_each_entry(mfile
, &card
->files_list
, list
) {
508 /* it's critical part, use endless loop */
509 /* we have no room to fail */
510 mfile
->disconnected_f_op
= mfile
->file
->f_op
;
512 spin_lock(&shutdown_lock
);
513 list_add(&mfile
->shutdown_list
, &shutdown_files
);
514 spin_unlock(&shutdown_lock
);
516 mfile
->file
->f_op
= &snd_shutdown_f_ops
;
517 fops_get(mfile
->file
->f_op
);
519 spin_unlock(&card
->files_lock
);
521 /* notify all connected devices about disconnection */
522 /* at this point, they cannot respond to any calls except release() */
524 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
525 if (snd_mixer_oss_notify_callback
)
526 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_DISCONNECT
);
529 /* notify all devices that we are disconnected */
530 snd_device_disconnect_all(card
);
532 if (card
->sync_irq
> 0)
533 synchronize_irq(card
->sync_irq
);
535 snd_info_card_disconnect(card
);
536 if (card
->registered
) {
537 device_del(&card
->card_dev
);
538 card
->registered
= false;
541 /* disable fops (user space) operations for ALSA API */
542 mutex_lock(&snd_card_mutex
);
543 snd_cards
[card
->number
] = NULL
;
544 clear_bit(card
->number
, snd_cards_lock
);
545 mutex_unlock(&snd_card_mutex
);
548 wake_up(&card
->power_sleep
);
549 snd_power_sync_ref(card
);
553 EXPORT_SYMBOL(snd_card_disconnect
);
556 * snd_card_disconnect_sync - disconnect card and wait until files get closed
557 * @card: card object to disconnect
559 * This calls snd_card_disconnect() for disconnecting all belonging components
560 * and waits until all pending files get closed.
561 * It assures that all accesses from user-space finished so that the driver
562 * can release its resources gracefully.
564 void snd_card_disconnect_sync(struct snd_card
*card
)
568 err
= snd_card_disconnect(card
);
571 "snd_card_disconnect error (%d), skipping sync\n",
576 spin_lock_irq(&card
->files_lock
);
577 wait_event_lock_irq(card
->remove_sleep
,
578 list_empty(&card
->files_list
),
580 spin_unlock_irq(&card
->files_lock
);
582 EXPORT_SYMBOL_GPL(snd_card_disconnect_sync
);
584 static int snd_card_do_free(struct snd_card
*card
)
586 card
->releasing
= true;
587 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
588 if (snd_mixer_oss_notify_callback
)
589 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_FREE
);
591 snd_device_free_all(card
);
592 if (card
->private_free
)
593 card
->private_free(card
);
594 if (snd_info_card_free(card
) < 0) {
595 dev_warn(card
->dev
, "unable to free card info\n");
596 /* Not fatal error */
598 #ifdef CONFIG_SND_DEBUG
599 debugfs_remove(card
->debugfs_root
);
600 card
->debugfs_root
= NULL
;
602 if (card
->release_completion
)
603 complete(card
->release_completion
);
610 * snd_card_free_when_closed - Disconnect the card, free it later eventually
611 * @card: soundcard structure
613 * Unlike snd_card_free(), this function doesn't try to release the card
614 * resource immediately, but tries to disconnect at first. When the card
615 * is still in use, the function returns before freeing the resources.
616 * The card resources will be freed when the refcount gets to zero.
618 * Return: zero if successful, or a negative error code
620 int snd_card_free_when_closed(struct snd_card
*card
)
622 int ret
= snd_card_disconnect(card
);
625 put_device(&card
->card_dev
);
628 EXPORT_SYMBOL(snd_card_free_when_closed
);
631 * snd_card_free - frees given soundcard structure
632 * @card: soundcard structure
634 * This function releases the soundcard structure and the all assigned
635 * devices automatically. That is, you don't have to release the devices
638 * This function waits until the all resources are properly released.
640 * Return: Zero. Frees all associated devices and frees the control
641 * interface associated to given soundcard.
643 int snd_card_free(struct snd_card
*card
)
645 DECLARE_COMPLETION_ONSTACK(released
);
648 /* The call of snd_card_free() is allowed from various code paths;
649 * a manual call from the driver and the call via devres_free, and
650 * we need to avoid double-free. Moreover, the release via devres
651 * may call snd_card_free() twice due to its nature, we need to have
652 * the check here at the beginning.
657 card
->release_completion
= &released
;
658 ret
= snd_card_free_when_closed(card
);
661 /* wait, until all devices are ready for the free operation */
662 wait_for_completion(&released
);
666 EXPORT_SYMBOL(snd_card_free
);
668 /* retrieve the last word of shortname or longname */
669 static const char *retrieve_id_from_card_name(const char *name
)
671 const char *spos
= name
;
674 if (isspace(*name
) && isalnum(name
[1]))
681 /* return true if the given id string doesn't conflict any other card ids */
682 static bool card_id_ok(struct snd_card
*card
, const char *id
)
685 if (!snd_info_check_reserved_words(id
))
687 for (i
= 0; i
< snd_ecards_limit
; i
++) {
688 if (snd_cards
[i
] && snd_cards
[i
] != card
&&
689 !strcmp(snd_cards
[i
]->id
, id
))
695 /* copy to card->id only with valid letters from nid */
696 static void copy_valid_id_string(struct snd_card
*card
, const char *src
,
701 while (*nid
&& !isalnum(*nid
))
704 *id
++ = isalpha(*src
) ? *src
: 'D';
705 while (*nid
&& (size_t)(id
- card
->id
) < sizeof(card
->id
) - 1) {
713 /* Set card->id from the given string
714 * If the string conflicts with other ids, add a suffix to make it unique.
716 static void snd_card_set_id_no_lock(struct snd_card
*card
, const char *src
,
720 bool is_default
= false;
723 copy_valid_id_string(card
, src
, nid
);
727 /* use "Default" for obviously invalid strings
728 * ("card" conflicts with proc directories)
730 if (!*id
|| !strncmp(id
, "card", 4)) {
731 strcpy(id
, "Default");
736 for (loops
= 0; loops
< SNDRV_CARDS
; loops
++) {
738 char sfxstr
[5]; /* "_012" */
741 if (card_id_ok(card
, id
))
744 /* Add _XYZ suffix */
745 sprintf(sfxstr
, "_%X", loops
+ 1);
746 sfxlen
= strlen(sfxstr
);
747 if (len
+ sfxlen
>= sizeof(card
->id
))
748 spos
= id
+ sizeof(card
->id
) - sfxlen
- 1;
751 strcpy(spos
, sfxstr
);
753 /* fallback to the default id */
759 dev_err(card
->dev
, "unable to set card id (%s)\n", id
);
760 if (card
->proc_root
->name
)
761 strscpy(card
->id
, card
->proc_root
->name
, sizeof(card
->id
));
765 * snd_card_set_id - set card identification name
766 * @card: soundcard structure
767 * @nid: new identification string
769 * This function sets the card identification and checks for name
772 void snd_card_set_id(struct snd_card
*card
, const char *nid
)
774 /* check if user specified own card->id */
775 if (card
->id
[0] != '\0')
777 mutex_lock(&snd_card_mutex
);
778 snd_card_set_id_no_lock(card
, nid
, nid
);
779 mutex_unlock(&snd_card_mutex
);
781 EXPORT_SYMBOL(snd_card_set_id
);
783 static ssize_t
id_show(struct device
*dev
,
784 struct device_attribute
*attr
, char *buf
)
786 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
787 return sysfs_emit(buf
, "%s\n", card
->id
);
790 static ssize_t
id_store(struct device
*dev
, struct device_attribute
*attr
,
791 const char *buf
, size_t count
)
793 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
794 char buf1
[sizeof(card
->id
)];
795 size_t copy
= count
> sizeof(card
->id
) - 1 ?
796 sizeof(card
->id
) - 1 : count
;
800 for (idx
= 0; idx
< copy
; idx
++) {
802 if (!isalnum(c
) && c
!= '_' && c
!= '-')
805 memcpy(buf1
, buf
, copy
);
807 mutex_lock(&snd_card_mutex
);
808 if (!card_id_ok(NULL
, buf1
)) {
809 mutex_unlock(&snd_card_mutex
);
812 strcpy(card
->id
, buf1
);
813 snd_info_card_id_change(card
);
814 mutex_unlock(&snd_card_mutex
);
819 static DEVICE_ATTR_RW(id
);
821 static ssize_t
number_show(struct device
*dev
,
822 struct device_attribute
*attr
, char *buf
)
824 struct snd_card
*card
= container_of(dev
, struct snd_card
, card_dev
);
825 return sysfs_emit(buf
, "%i\n", card
->number
);
828 static DEVICE_ATTR_RO(number
);
830 static struct attribute
*card_dev_attrs
[] = {
832 &dev_attr_number
.attr
,
836 static const struct attribute_group card_dev_attr_group
= {
837 .attrs
= card_dev_attrs
,
841 * snd_card_add_dev_attr - Append a new sysfs attribute group to card
842 * @card: card instance
843 * @group: attribute group to append
845 * Return: zero if successful, or a negative error code
847 int snd_card_add_dev_attr(struct snd_card
*card
,
848 const struct attribute_group
*group
)
852 /* loop for (arraysize-1) here to keep NULL at the last entry */
853 for (i
= 0; i
< ARRAY_SIZE(card
->dev_groups
) - 1; i
++) {
854 if (!card
->dev_groups
[i
]) {
855 card
->dev_groups
[i
] = group
;
860 dev_err(card
->dev
, "Too many groups assigned\n");
863 EXPORT_SYMBOL_GPL(snd_card_add_dev_attr
);
865 static void trigger_card_free(void *data
)
871 * snd_card_register - register the soundcard
872 * @card: soundcard structure
874 * This function registers all the devices assigned to the soundcard.
875 * Until calling this, the ALSA control interface is blocked from the
876 * external accesses. Thus, you should call this function at the end
877 * of the initialization of the card.
879 * Return: Zero otherwise a negative error code if the registration failed.
881 int snd_card_register(struct snd_card
*card
)
885 if (snd_BUG_ON(!card
))
888 if (!card
->registered
) {
889 err
= device_add(&card
->card_dev
);
892 card
->registered
= true;
895 devm_remove_action(card
->dev
, trigger_card_free
, card
);
899 err
= devm_add_action(card
->dev
, trigger_card_free
, card
);
904 err
= snd_device_register_all(card
);
907 mutex_lock(&snd_card_mutex
);
908 if (snd_cards
[card
->number
]) {
909 /* already registered */
910 mutex_unlock(&snd_card_mutex
);
911 return snd_info_card_register(card
); /* register pending info */
914 /* make a unique id name from the given string */
915 char tmpid
[sizeof(card
->id
)];
916 memcpy(tmpid
, card
->id
, sizeof(card
->id
));
917 snd_card_set_id_no_lock(card
, tmpid
, tmpid
);
919 /* create an id from either shortname or longname */
921 src
= *card
->shortname
? card
->shortname
: card
->longname
;
922 snd_card_set_id_no_lock(card
, src
,
923 retrieve_id_from_card_name(src
));
925 snd_cards
[card
->number
] = card
;
926 mutex_unlock(&snd_card_mutex
);
927 err
= snd_info_card_register(card
);
931 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
932 if (snd_mixer_oss_notify_callback
)
933 snd_mixer_oss_notify_callback(card
, SND_MIXER_OSS_NOTIFY_REGISTER
);
937 EXPORT_SYMBOL(snd_card_register
);
939 #ifdef CONFIG_SND_PROC_FS
940 static void snd_card_info_read(struct snd_info_entry
*entry
,
941 struct snd_info_buffer
*buffer
)
944 struct snd_card
*card
;
946 for (idx
= count
= 0; idx
< SNDRV_CARDS
; idx
++) {
947 mutex_lock(&snd_card_mutex
);
948 card
= snd_cards
[idx
];
951 snd_iprintf(buffer
, "%2i [%-15s]: %s - %s\n",
956 snd_iprintf(buffer
, " %s\n",
959 mutex_unlock(&snd_card_mutex
);
962 snd_iprintf(buffer
, "--- no soundcards ---\n");
965 #ifdef CONFIG_SND_OSSEMUL
966 void snd_card_info_read_oss(struct snd_info_buffer
*buffer
)
969 struct snd_card
*card
;
971 for (idx
= count
= 0; idx
< SNDRV_CARDS
; idx
++) {
972 mutex_lock(&snd_card_mutex
);
973 card
= snd_cards
[idx
];
976 snd_iprintf(buffer
, "%s\n", card
->longname
);
978 mutex_unlock(&snd_card_mutex
);
981 snd_iprintf(buffer
, "--- no soundcards ---\n");
988 static void snd_card_module_info_read(struct snd_info_entry
*entry
,
989 struct snd_info_buffer
*buffer
)
992 struct snd_card
*card
;
994 for (idx
= 0; idx
< SNDRV_CARDS
; idx
++) {
995 mutex_lock(&snd_card_mutex
);
996 card
= snd_cards
[idx
];
998 snd_iprintf(buffer
, "%2i %s\n",
999 idx
, card
->module
->name
);
1000 mutex_unlock(&snd_card_mutex
);
1005 int __init
snd_card_info_init(void)
1007 struct snd_info_entry
*entry
;
1009 entry
= snd_info_create_module_entry(THIS_MODULE
, "cards", NULL
);
1012 entry
->c
.text
.read
= snd_card_info_read
;
1013 if (snd_info_register(entry
) < 0)
1014 return -ENOMEM
; /* freed in error path */
1017 entry
= snd_info_create_module_entry(THIS_MODULE
, "modules", NULL
);
1020 entry
->c
.text
.read
= snd_card_module_info_read
;
1021 if (snd_info_register(entry
) < 0)
1022 return -ENOMEM
; /* freed in error path */
1027 #endif /* CONFIG_SND_PROC_FS */
1030 * snd_component_add - add a component string
1031 * @card: soundcard structure
1032 * @component: the component id string
1034 * This function adds the component id string to the supported list.
1035 * The component can be referred from the alsa-lib.
1037 * Return: Zero otherwise a negative error code.
1040 int snd_component_add(struct snd_card
*card
, const char *component
)
1043 int len
= strlen(component
);
1045 ptr
= strstr(card
->components
, component
);
1047 if (ptr
[len
] == '\0' || ptr
[len
] == ' ') /* already there */
1050 if (strlen(card
->components
) + 1 + len
+ 1 > sizeof(card
->components
)) {
1054 if (card
->components
[0] != '\0')
1055 strcat(card
->components
, " ");
1056 strcat(card
->components
, component
);
1059 EXPORT_SYMBOL(snd_component_add
);
1062 * snd_card_file_add - add the file to the file list of the card
1063 * @card: soundcard structure
1064 * @file: file pointer
1066 * This function adds the file to the file linked-list of the card.
1067 * This linked-list is used to keep tracking the connection state,
1068 * and to avoid the release of busy resources by hotplug.
1070 * Return: zero or a negative error code.
1072 int snd_card_file_add(struct snd_card
*card
, struct file
*file
)
1074 struct snd_monitor_file
*mfile
;
1076 mfile
= kmalloc(sizeof(*mfile
), GFP_KERNEL
);
1080 mfile
->disconnected_f_op
= NULL
;
1081 INIT_LIST_HEAD(&mfile
->shutdown_list
);
1082 spin_lock(&card
->files_lock
);
1083 if (card
->shutdown
) {
1084 spin_unlock(&card
->files_lock
);
1088 list_add(&mfile
->list
, &card
->files_list
);
1089 get_device(&card
->card_dev
);
1090 spin_unlock(&card
->files_lock
);
1093 EXPORT_SYMBOL(snd_card_file_add
);
1096 * snd_card_file_remove - remove the file from the file list
1097 * @card: soundcard structure
1098 * @file: file pointer
1100 * This function removes the file formerly added to the card via
1101 * snd_card_file_add() function.
1102 * If all files are removed and snd_card_free_when_closed() was
1103 * called beforehand, it processes the pending release of
1106 * Return: Zero or a negative error code.
1108 int snd_card_file_remove(struct snd_card
*card
, struct file
*file
)
1110 struct snd_monitor_file
*mfile
, *found
= NULL
;
1112 spin_lock(&card
->files_lock
);
1113 list_for_each_entry(mfile
, &card
->files_list
, list
) {
1114 if (mfile
->file
== file
) {
1115 list_del(&mfile
->list
);
1116 spin_lock(&shutdown_lock
);
1117 list_del(&mfile
->shutdown_list
);
1118 spin_unlock(&shutdown_lock
);
1119 if (mfile
->disconnected_f_op
)
1120 fops_put(mfile
->disconnected_f_op
);
1125 if (list_empty(&card
->files_list
))
1126 wake_up_all(&card
->remove_sleep
);
1127 spin_unlock(&card
->files_lock
);
1129 dev_err(card
->dev
, "card file remove problem (%p)\n", file
);
1133 put_device(&card
->card_dev
);
1136 EXPORT_SYMBOL(snd_card_file_remove
);
1140 * snd_power_ref_and_wait - wait until the card gets powered up
1141 * @card: soundcard structure
1143 * Take the power_ref reference count of the given card, and
1144 * wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1145 * The refcount is down again while sleeping until power-up, hence this
1146 * function can be used for syncing the floating control ops accesses,
1147 * typically around calling control ops.
1149 * The caller needs to pull down the refcount via snd_power_unref() later
1150 * no matter whether the error is returned from this function or not.
1152 * Return: Zero if successful, or a negative error code.
1154 int snd_power_ref_and_wait(struct snd_card
*card
)
1156 snd_power_ref(card
);
1157 if (snd_power_get_state(card
) == SNDRV_CTL_POWER_D0
)
1159 wait_event_cmd(card
->power_sleep
,
1161 snd_power_get_state(card
) == SNDRV_CTL_POWER_D0
,
1162 snd_power_unref(card
), snd_power_ref(card
));
1163 return card
->shutdown
? -ENODEV
: 0;
1165 EXPORT_SYMBOL_GPL(snd_power_ref_and_wait
);
1168 * snd_power_wait - wait until the card gets powered up (old form)
1169 * @card: soundcard structure
1171 * Wait until the card gets powered up to SNDRV_CTL_POWER_D0 state.
1173 * Return: Zero if successful, or a negative error code.
1175 int snd_power_wait(struct snd_card
*card
)
1179 ret
= snd_power_ref_and_wait(card
);
1180 snd_power_unref(card
);
1183 EXPORT_SYMBOL(snd_power_wait
);
1184 #endif /* CONFIG_PM */