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v3.15
  1/*
  2 *  Initialization routines
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  4 *
  5 *
  6 *   This program is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU General Public License as published by
  8 *   the Free Software Foundation; either version 2 of the License, or
  9 *   (at your option) any later version.
 10 *
 11 *   This program is distributed in the hope that it will be useful,
 12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *   GNU General Public License for more details.
 15 *
 16 *   You should have received a copy of the GNU General Public License
 17 *   along with this program; if not, write to the Free Software
 18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19 *
 20 */
 21
 22#include <linux/init.h>
 23#include <linux/sched.h>
 24#include <linux/module.h>
 25#include <linux/device.h>
 26#include <linux/file.h>
 27#include <linux/slab.h>
 28#include <linux/time.h>
 29#include <linux/ctype.h>
 30#include <linux/pm.h>
 31#include <linux/completion.h>
 32
 33#include <sound/core.h>
 34#include <sound/control.h>
 35#include <sound/info.h>
 36
 37/* monitor files for graceful shutdown (hotplug) */
 38struct snd_monitor_file {
 39	struct file *file;
 40	const struct file_operations *disconnected_f_op;
 41	struct list_head shutdown_list;	/* still need to shutdown */
 42	struct list_head list;	/* link of monitor files */
 43};
 44
 45static DEFINE_SPINLOCK(shutdown_lock);
 46static LIST_HEAD(shutdown_files);
 47
 48static const struct file_operations snd_shutdown_f_ops;
 49
 50/* locked for registering/using */
 51static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);
 52struct snd_card *snd_cards[SNDRV_CARDS];
 53EXPORT_SYMBOL(snd_cards);
 54
 55static DEFINE_MUTEX(snd_card_mutex);
 56
 57static char *slots[SNDRV_CARDS];
 58module_param_array(slots, charp, NULL, 0444);
 59MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
 60
 61/* return non-zero if the given index is reserved for the given
 62 * module via slots option
 63 */
 64static int module_slot_match(struct module *module, int idx)
 65{
 66	int match = 1;
 67#ifdef MODULE
 68	const char *s1, *s2;
 69
 70	if (!module || !*module->name || !slots[idx])
 71		return 0;
 72
 73	s1 = module->name;
 74	s2 = slots[idx];
 75	if (*s2 == '!') {
 76		match = 0; /* negative match */
 77		s2++;
 78	}
 79	/* compare module name strings
 80	 * hyphens are handled as equivalent with underscore
 81	 */
 82	for (;;) {
 83		char c1 = *s1++;
 84		char c2 = *s2++;
 85		if (c1 == '-')
 86			c1 = '_';
 87		if (c2 == '-')
 88			c2 = '_';
 89		if (c1 != c2)
 90			return !match;
 91		if (!c1)
 92			break;
 93	}
 94#endif /* MODULE */
 95	return match;
 96}
 97
 98#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
 99int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
100EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
101#endif
102
103#ifdef CONFIG_PROC_FS
104static void snd_card_id_read(struct snd_info_entry *entry,
105			     struct snd_info_buffer *buffer)
106{
107	snd_iprintf(buffer, "%s\n", entry->card->id);
108}
109
110static inline int init_info_for_card(struct snd_card *card)
111{
112	int err;
113	struct snd_info_entry *entry;
114
115	if ((err = snd_info_card_register(card)) < 0) {
116		dev_dbg(card->dev, "unable to create card info\n");
117		return err;
118	}
119	if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
120		dev_dbg(card->dev, "unable to create card entry\n");
121		return err;
122	}
123	entry->c.text.read = snd_card_id_read;
124	if (snd_info_register(entry) < 0) {
125		snd_info_free_entry(entry);
126		entry = NULL;
127	}
128	card->proc_id = entry;
129	return 0;
130}
131#else /* !CONFIG_PROC_FS */
132#define init_info_for_card(card)
133#endif
134
135static int check_empty_slot(struct module *module, int slot)
136{
137	return !slots[slot] || !*slots[slot];
138}
139
140/* return an empty slot number (>= 0) found in the given bitmask @mask.
141 * @mask == -1 == 0xffffffff means: take any free slot up to 32
142 * when no slot is available, return the original @mask as is.
143 */
144static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int),
145				 struct module *module)
146{
147	int slot;
148
149	for (slot = 0; slot < SNDRV_CARDS; slot++) {
150		if (slot < 32 && !(mask & (1U << slot)))
151			continue;
152		if (!test_bit(slot, snd_cards_lock)) {
153			if (check(module, slot))
154				return slot; /* found */
155		}
156	}
157	return mask; /* unchanged */
158}
159
160static int snd_card_do_free(struct snd_card *card);
161static const struct attribute_group *card_dev_attr_groups[];
162
163static void release_card_device(struct device *dev)
164{
165	snd_card_do_free(dev_to_snd_card(dev));
166}
167
168/**
169 *  snd_card_new - create and initialize a soundcard structure
170 *  @parent: the parent device object
171 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
172 *  @xid: card identification (ASCII string)
173 *  @module: top level module for locking
174 *  @extra_size: allocate this extra size after the main soundcard structure
175 *  @card_ret: the pointer to store the created card instance
176 *
177 *  Creates and initializes a soundcard structure.
178 *
179 *  The function allocates snd_card instance via kzalloc with the given
180 *  space for the driver to use freely.  The allocated struct is stored
181 *  in the given card_ret pointer.
182 *
183 *  Return: Zero if successful or a negative error code.
184 */
185int snd_card_new(struct device *parent, int idx, const char *xid,
186		    struct module *module, int extra_size,
187		    struct snd_card **card_ret)
188{
189	struct snd_card *card;
190	int err;
191
192	if (snd_BUG_ON(!card_ret))
193		return -EINVAL;
194	*card_ret = NULL;
195
196	if (extra_size < 0)
197		extra_size = 0;
198	card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
199	if (!card)
200		return -ENOMEM;
201	if (extra_size > 0)
202		card->private_data = (char *)card + sizeof(struct snd_card);
203	if (xid)
204		strlcpy(card->id, xid, sizeof(card->id));
205	err = 0;
206	mutex_lock(&snd_card_mutex);
207	if (idx < 0) /* first check the matching module-name slot */
208		idx = get_slot_from_bitmask(idx, module_slot_match, module);
209	if (idx < 0) /* if not matched, assign an empty slot */
210		idx = get_slot_from_bitmask(idx, check_empty_slot, module);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
211	if (idx < 0)
212		err = -ENODEV;
213	else if (idx < snd_ecards_limit) {
214		if (test_bit(idx, snd_cards_lock))
215			err = -EBUSY;	/* invalid */
216	} else if (idx >= SNDRV_CARDS)
217		err = -ENODEV;
218	if (err < 0) {
219		mutex_unlock(&snd_card_mutex);
220		dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n",
221			 idx, snd_ecards_limit - 1, err);
222		kfree(card);
223		return err;
224	}
225	set_bit(idx, snd_cards_lock);		/* lock it */
226	if (idx >= snd_ecards_limit)
227		snd_ecards_limit = idx + 1; /* increase the limit */
228	mutex_unlock(&snd_card_mutex);
229	card->dev = parent;
230	card->number = idx;
231	card->module = module;
232	INIT_LIST_HEAD(&card->devices);
233	init_rwsem(&card->controls_rwsem);
234	rwlock_init(&card->ctl_files_rwlock);
235	INIT_LIST_HEAD(&card->controls);
236	INIT_LIST_HEAD(&card->ctl_files);
237	spin_lock_init(&card->files_lock);
238	INIT_LIST_HEAD(&card->files_list);
 
239#ifdef CONFIG_PM
240	mutex_init(&card->power_lock);
241	init_waitqueue_head(&card->power_sleep);
242#endif
243
244	device_initialize(&card->card_dev);
245	card->card_dev.parent = parent;
246	card->card_dev.class = sound_class;
247	card->card_dev.release = release_card_device;
248	card->card_dev.groups = card_dev_attr_groups;
249	err = kobject_set_name(&card->card_dev.kobj, "card%d", idx);
250	if (err < 0)
251		goto __error;
252
253	/* the control interface cannot be accessed from the user space until */
254	/* snd_cards_bitmask and snd_cards are set with snd_card_register */
255	err = snd_ctl_create(card);
256	if (err < 0) {
257		dev_err(parent, "unable to register control minors\n");
258		goto __error;
259	}
260	err = snd_info_card_create(card);
261	if (err < 0) {
262		dev_err(parent, "unable to create card info\n");
263		goto __error_ctl;
264	}
 
 
265	*card_ret = card;
266	return 0;
267
268      __error_ctl:
269	snd_device_free_all(card);
270      __error:
271	put_device(&card->card_dev);
272  	return err;
273}
274EXPORT_SYMBOL(snd_card_new);
275
276/* return non-zero if a card is already locked */
277int snd_card_locked(int card)
278{
279	int locked;
280
281	mutex_lock(&snd_card_mutex);
282	locked = test_bit(card, snd_cards_lock);
283	mutex_unlock(&snd_card_mutex);
284	return locked;
285}
286
287static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
288{
289	return -ENODEV;
290}
291
292static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
293				   size_t count, loff_t *offset)
294{
295	return -ENODEV;
296}
297
298static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
299				    size_t count, loff_t *offset)
300{
301	return -ENODEV;
302}
303
304static int snd_disconnect_release(struct inode *inode, struct file *file)
305{
306	struct snd_monitor_file *df = NULL, *_df;
307
308	spin_lock(&shutdown_lock);
309	list_for_each_entry(_df, &shutdown_files, shutdown_list) {
310		if (_df->file == file) {
311			df = _df;
312			list_del_init(&df->shutdown_list);
313			break;
314		}
315	}
316	spin_unlock(&shutdown_lock);
317
318	if (likely(df)) {
319		if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
320			df->disconnected_f_op->fasync(-1, file, 0);
321		return df->disconnected_f_op->release(inode, file);
322	}
323
324	panic("%s(%p, %p) failed!", __func__, inode, file);
325}
326
327static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
328{
329	return POLLERR | POLLNVAL;
330}
331
332static long snd_disconnect_ioctl(struct file *file,
333				 unsigned int cmd, unsigned long arg)
334{
335	return -ENODEV;
336}
337
338static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
339{
340	return -ENODEV;
341}
342
343static int snd_disconnect_fasync(int fd, struct file *file, int on)
344{
345	return -ENODEV;
346}
347
348static const struct file_operations snd_shutdown_f_ops =
349{
350	.owner = 	THIS_MODULE,
351	.llseek =	snd_disconnect_llseek,
352	.read = 	snd_disconnect_read,
353	.write =	snd_disconnect_write,
354	.release =	snd_disconnect_release,
355	.poll =		snd_disconnect_poll,
356	.unlocked_ioctl = snd_disconnect_ioctl,
357#ifdef CONFIG_COMPAT
358	.compat_ioctl = snd_disconnect_ioctl,
359#endif
360	.mmap =		snd_disconnect_mmap,
361	.fasync =	snd_disconnect_fasync
362};
363
364/**
365 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
366 *  @card: soundcard structure
367 *
368 *  Disconnects all APIs from the file-operations (user space).
369 *
370 *  Return: Zero, otherwise a negative error code.
371 *
372 *  Note: The current implementation replaces all active file->f_op with special
373 *        dummy file operations (they do nothing except release).
374 */
375int snd_card_disconnect(struct snd_card *card)
376{
377	struct snd_monitor_file *mfile;
378	int err;
379
380	if (!card)
381		return -EINVAL;
382
383	spin_lock(&card->files_lock);
384	if (card->shutdown) {
385		spin_unlock(&card->files_lock);
386		return 0;
387	}
388	card->shutdown = 1;
389	spin_unlock(&card->files_lock);
390
391	/* phase 1: disable fops (user space) operations for ALSA API */
392	mutex_lock(&snd_card_mutex);
393	snd_cards[card->number] = NULL;
394	clear_bit(card->number, snd_cards_lock);
395	mutex_unlock(&snd_card_mutex);
396	
397	/* phase 2: replace file->f_op with special dummy operations */
398	
399	spin_lock(&card->files_lock);
400	list_for_each_entry(mfile, &card->files_list, list) {
401		/* it's critical part, use endless loop */
402		/* we have no room to fail */
403		mfile->disconnected_f_op = mfile->file->f_op;
404
405		spin_lock(&shutdown_lock);
406		list_add(&mfile->shutdown_list, &shutdown_files);
407		spin_unlock(&shutdown_lock);
408
409		mfile->file->f_op = &snd_shutdown_f_ops;
410		fops_get(mfile->file->f_op);
411	}
412	spin_unlock(&card->files_lock);	
413
414	/* phase 3: notify all connected devices about disconnection */
415	/* at this point, they cannot respond to any calls except release() */
416
417#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
418	if (snd_mixer_oss_notify_callback)
419		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
420#endif
421
422	/* notify all devices that we are disconnected */
423	err = snd_device_disconnect_all(card);
424	if (err < 0)
425		dev_err(card->dev, "not all devices for card %i can be disconnected\n", card->number);
426
427	snd_info_card_disconnect(card);
428	if (card->registered) {
429		device_del(&card->card_dev);
430		card->registered = false;
431	}
432#ifdef CONFIG_PM
433	wake_up(&card->power_sleep);
434#endif
435	return 0;	
436}
437
438EXPORT_SYMBOL(snd_card_disconnect);
439
440/**
441 *  snd_card_free - frees given soundcard structure
442 *  @card: soundcard structure
443 *
444 *  This function releases the soundcard structure and the all assigned
445 *  devices automatically.  That is, you don't have to release the devices
446 *  by yourself.
447 *
448 *  Return: Zero. Frees all associated devices and frees the control
449 *  interface associated to given soundcard.
450 */
451static int snd_card_do_free(struct snd_card *card)
452{
453#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
454	if (snd_mixer_oss_notify_callback)
455		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
456#endif
457	snd_device_free_all(card);
 
 
 
 
 
 
 
 
 
 
 
458	if (card->private_free)
459		card->private_free(card);
460	snd_info_free_entry(card->proc_id);
461	if (snd_info_card_free(card) < 0) {
462		dev_warn(card->dev, "unable to free card info\n");
463		/* Not fatal error */
464	}
465	if (card->release_completion)
466		complete(card->release_completion);
467	kfree(card);
468	return 0;
469}
470
471int snd_card_free_when_closed(struct snd_card *card)
472{
 
473	int ret = snd_card_disconnect(card);
474	if (ret)
475		return ret;
476	put_device(&card->card_dev);
 
 
 
 
 
 
 
 
 
477	return 0;
478}
 
479EXPORT_SYMBOL(snd_card_free_when_closed);
480
481int snd_card_free(struct snd_card *card)
482{
483	struct completion released;
484	int ret;
485
486	init_completion(&released);
487	card->release_completion = &released;
488	ret = snd_card_free_when_closed(card);
489	if (ret)
490		return ret;
 
491	/* wait, until all devices are ready for the free operation */
492	wait_for_completion(&released);
 
493	return 0;
494}
495EXPORT_SYMBOL(snd_card_free);
496
497/* retrieve the last word of shortname or longname */
498static const char *retrieve_id_from_card_name(const char *name)
499{
500	const char *spos = name;
501
502	while (*name) {
503		if (isspace(*name) && isalnum(name[1]))
504			spos = name + 1;
505		name++;
506	}
507	return spos;
508}
509
510/* return true if the given id string doesn't conflict any other card ids */
511static bool card_id_ok(struct snd_card *card, const char *id)
512{
513	int i;
514	if (!snd_info_check_reserved_words(id))
515		return false;
516	for (i = 0; i < snd_ecards_limit; i++) {
517		if (snd_cards[i] && snd_cards[i] != card &&
518		    !strcmp(snd_cards[i]->id, id))
519			return false;
520	}
521	return true;
522}
523
524/* copy to card->id only with valid letters from nid */
525static void copy_valid_id_string(struct snd_card *card, const char *src,
526				 const char *nid)
527{
528	char *id = card->id;
529
530	while (*nid && !isalnum(*nid))
531		nid++;
532	if (isdigit(*nid))
533		*id++ = isalpha(*src) ? *src : 'D';
534	while (*nid && (size_t)(id - card->id) < sizeof(card->id) - 1) {
535		if (isalnum(*nid))
536			*id++ = *nid;
537		nid++;
538	}
539	*id = 0;
540}
541
542/* Set card->id from the given string
543 * If the string conflicts with other ids, add a suffix to make it unique.
544 */
545static void snd_card_set_id_no_lock(struct snd_card *card, const char *src,
546				    const char *nid)
547{
548	int len, loops;
549	bool is_default = false;
550	char *id;
551	
552	copy_valid_id_string(card, src, nid);
 
 
 
 
 
 
 
 
 
 
553	id = card->id;
 
 
 
 
 
 
 
 
 
 
554
555 again:
556	/* use "Default" for obviously invalid strings
557	 * ("card" conflicts with proc directories)
558	 */
559	if (!*id || !strncmp(id, "card", 4)) {
560		strcpy(id, "Default");
561		is_default = true;
562	}
563
564	len = strlen(id);
565	for (loops = 0; loops < SNDRV_CARDS; loops++) {
566		char *spos;
567		char sfxstr[5]; /* "_012" */
568		int sfxlen;
569
570		if (card_id_ok(card, id))
571			return; /* OK */
572
573		/* Add _XYZ suffix */
574		sprintf(sfxstr, "_%X", loops + 1);
575		sfxlen = strlen(sfxstr);
576		if (len + sfxlen >= sizeof(card->id))
577			spos = id + sizeof(card->id) - sfxlen - 1;
578		else
579			spos = id + len;
580		strcpy(spos, sfxstr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
581	}
582	/* fallback to the default id */
583	if (!is_default) {
584		*id = 0;
585		goto again;
586	}
587	/* last resort... */
588	dev_err(card->dev, "unable to set card id (%s)\n", id);
589	if (card->proc_root->name)
590		strlcpy(card->id, card->proc_root->name, sizeof(card->id));
591}
592
593/**
594 *  snd_card_set_id - set card identification name
595 *  @card: soundcard structure
596 *  @nid: new identification string
597 *
598 *  This function sets the card identification and checks for name
599 *  collisions.
600 */
601void snd_card_set_id(struct snd_card *card, const char *nid)
602{
603	/* check if user specified own card->id */
604	if (card->id[0] != '\0')
605		return;
606	mutex_lock(&snd_card_mutex);
607	snd_card_set_id_no_lock(card, nid, nid);
608	mutex_unlock(&snd_card_mutex);
609}
610EXPORT_SYMBOL(snd_card_set_id);
611
612static ssize_t
613card_id_show_attr(struct device *dev,
614		  struct device_attribute *attr, char *buf)
615{
616	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
617	return snprintf(buf, PAGE_SIZE, "%s\n", card->id);
618}
619
620static ssize_t
621card_id_store_attr(struct device *dev, struct device_attribute *attr,
622		   const char *buf, size_t count)
623{
624	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
625	char buf1[sizeof(card->id)];
626	size_t copy = count > sizeof(card->id) - 1 ?
627					sizeof(card->id) - 1 : count;
628	size_t idx;
629	int c;
630
631	for (idx = 0; idx < copy; idx++) {
632		c = buf[idx];
633		if (!isalnum(c) && c != '_' && c != '-')
634			return -EINVAL;
635	}
636	memcpy(buf1, buf, copy);
637	buf1[copy] = '\0';
638	mutex_lock(&snd_card_mutex);
639	if (!card_id_ok(NULL, buf1)) {
 
640		mutex_unlock(&snd_card_mutex);
641		return -EEXIST;
642	}
 
 
 
 
 
 
 
 
643	strcpy(card->id, buf1);
644	snd_info_card_id_change(card);
 
645	mutex_unlock(&snd_card_mutex);
646
647	return count;
648}
649
650static DEVICE_ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
 
651
652static ssize_t
653card_number_show_attr(struct device *dev,
654		     struct device_attribute *attr, char *buf)
655{
656	struct snd_card *card = container_of(dev, struct snd_card, card_dev);
657	return snprintf(buf, PAGE_SIZE, "%i\n", card->number);
658}
659
660static DEVICE_ATTR(number, S_IRUGO, card_number_show_attr, NULL);
661
662static struct attribute *card_dev_attrs[] = {
663	&dev_attr_id.attr,
664	&dev_attr_number.attr,
665	NULL
666};
667
668static struct attribute_group card_dev_attr_group = {
669	.attrs	= card_dev_attrs,
670};
671
672static const struct attribute_group *card_dev_attr_groups[] = {
673	&card_dev_attr_group,
674	NULL
675};
676
677/**
678 *  snd_card_register - register the soundcard
679 *  @card: soundcard structure
680 *
681 *  This function registers all the devices assigned to the soundcard.
682 *  Until calling this, the ALSA control interface is blocked from the
683 *  external accesses.  Thus, you should call this function at the end
684 *  of the initialization of the card.
685 *
686 *  Return: Zero otherwise a negative error code if the registration failed.
687 */
688int snd_card_register(struct snd_card *card)
689{
690	int err;
691
692	if (snd_BUG_ON(!card))
693		return -EINVAL;
694
695	if (!card->registered) {
696		err = device_add(&card->card_dev);
697		if (err < 0)
698			return err;
699		card->registered = true;
 
700	}
701
702	if ((err = snd_device_register_all(card)) < 0)
703		return err;
704	mutex_lock(&snd_card_mutex);
705	if (snd_cards[card->number]) {
706		/* already registered */
707		mutex_unlock(&snd_card_mutex);
708		return 0;
709	}
710	if (*card->id) {
711		/* make a unique id name from the given string */
712		char tmpid[sizeof(card->id)];
713		memcpy(tmpid, card->id, sizeof(card->id));
714		snd_card_set_id_no_lock(card, tmpid, tmpid);
715	} else {
716		/* create an id from either shortname or longname */
717		const char *src;
718		src = *card->shortname ? card->shortname : card->longname;
719		snd_card_set_id_no_lock(card, src,
720					retrieve_id_from_card_name(src));
721	}
722	snd_cards[card->number] = card;
723	mutex_unlock(&snd_card_mutex);
724	init_info_for_card(card);
725#if IS_ENABLED(CONFIG_SND_MIXER_OSS)
726	if (snd_mixer_oss_notify_callback)
727		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
728#endif
 
 
 
 
 
 
 
 
 
729	return 0;
730}
731
732EXPORT_SYMBOL(snd_card_register);
733
734#ifdef CONFIG_PROC_FS
735static struct snd_info_entry *snd_card_info_entry;
736
737static void snd_card_info_read(struct snd_info_entry *entry,
738			       struct snd_info_buffer *buffer)
739{
740	int idx, count;
741	struct snd_card *card;
742
743	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
744		mutex_lock(&snd_card_mutex);
745		if ((card = snd_cards[idx]) != NULL) {
746			count++;
747			snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
748					idx,
749					card->id,
750					card->driver,
751					card->shortname);
752			snd_iprintf(buffer, "                      %s\n",
753					card->longname);
754		}
755		mutex_unlock(&snd_card_mutex);
756	}
757	if (!count)
758		snd_iprintf(buffer, "--- no soundcards ---\n");
759}
760
761#ifdef CONFIG_SND_OSSEMUL
762
763void snd_card_info_read_oss(struct snd_info_buffer *buffer)
764{
765	int idx, count;
766	struct snd_card *card;
767
768	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
769		mutex_lock(&snd_card_mutex);
770		if ((card = snd_cards[idx]) != NULL) {
771			count++;
772			snd_iprintf(buffer, "%s\n", card->longname);
773		}
774		mutex_unlock(&snd_card_mutex);
775	}
776	if (!count) {
777		snd_iprintf(buffer, "--- no soundcards ---\n");
778	}
779}
780
781#endif
782
783#ifdef MODULE
784static struct snd_info_entry *snd_card_module_info_entry;
785static void snd_card_module_info_read(struct snd_info_entry *entry,
786				      struct snd_info_buffer *buffer)
787{
788	int idx;
789	struct snd_card *card;
790
791	for (idx = 0; idx < SNDRV_CARDS; idx++) {
792		mutex_lock(&snd_card_mutex);
793		if ((card = snd_cards[idx]) != NULL)
794			snd_iprintf(buffer, "%2i %s\n",
795				    idx, card->module->name);
796		mutex_unlock(&snd_card_mutex);
797	}
798}
799#endif
800
801int __init snd_card_info_init(void)
802{
803	struct snd_info_entry *entry;
804
805	entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
806	if (! entry)
807		return -ENOMEM;
808	entry->c.text.read = snd_card_info_read;
809	if (snd_info_register(entry) < 0) {
810		snd_info_free_entry(entry);
811		return -ENOMEM;
812	}
813	snd_card_info_entry = entry;
814
815#ifdef MODULE
816	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
817	if (entry) {
818		entry->c.text.read = snd_card_module_info_read;
819		if (snd_info_register(entry) < 0)
820			snd_info_free_entry(entry);
821		else
822			snd_card_module_info_entry = entry;
823	}
824#endif
825
826	return 0;
827}
828
829int __exit snd_card_info_done(void)
830{
831	snd_info_free_entry(snd_card_info_entry);
832#ifdef MODULE
833	snd_info_free_entry(snd_card_module_info_entry);
834#endif
835	return 0;
836}
837
838#endif /* CONFIG_PROC_FS */
839
840/**
841 *  snd_component_add - add a component string
842 *  @card: soundcard structure
843 *  @component: the component id string
844 *
845 *  This function adds the component id string to the supported list.
846 *  The component can be referred from the alsa-lib.
847 *
848 *  Return: Zero otherwise a negative error code.
849 */
850  
851int snd_component_add(struct snd_card *card, const char *component)
852{
853	char *ptr;
854	int len = strlen(component);
855
856	ptr = strstr(card->components, component);
857	if (ptr != NULL) {
858		if (ptr[len] == '\0' || ptr[len] == ' ')	/* already there */
859			return 1;
860	}
861	if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
862		snd_BUG();
863		return -ENOMEM;
864	}
865	if (card->components[0] != '\0')
866		strcat(card->components, " ");
867	strcat(card->components, component);
868	return 0;
869}
870
871EXPORT_SYMBOL(snd_component_add);
872
873/**
874 *  snd_card_file_add - add the file to the file list of the card
875 *  @card: soundcard structure
876 *  @file: file pointer
877 *
878 *  This function adds the file to the file linked-list of the card.
879 *  This linked-list is used to keep tracking the connection state,
880 *  and to avoid the release of busy resources by hotplug.
881 *
882 *  Return: zero or a negative error code.
883 */
884int snd_card_file_add(struct snd_card *card, struct file *file)
885{
886	struct snd_monitor_file *mfile;
887
888	mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
889	if (mfile == NULL)
890		return -ENOMEM;
891	mfile->file = file;
892	mfile->disconnected_f_op = NULL;
893	INIT_LIST_HEAD(&mfile->shutdown_list);
894	spin_lock(&card->files_lock);
895	if (card->shutdown) {
896		spin_unlock(&card->files_lock);
897		kfree(mfile);
898		return -ENODEV;
899	}
900	list_add(&mfile->list, &card->files_list);
901	get_device(&card->card_dev);
902	spin_unlock(&card->files_lock);
903	return 0;
904}
905
906EXPORT_SYMBOL(snd_card_file_add);
907
908/**
909 *  snd_card_file_remove - remove the file from the file list
910 *  @card: soundcard structure
911 *  @file: file pointer
912 *
913 *  This function removes the file formerly added to the card via
914 *  snd_card_file_add() function.
915 *  If all files are removed and snd_card_free_when_closed() was
916 *  called beforehand, it processes the pending release of
917 *  resources.
918 *
919 *  Return: Zero or a negative error code.
920 */
921int snd_card_file_remove(struct snd_card *card, struct file *file)
922{
923	struct snd_monitor_file *mfile, *found = NULL;
 
924
925	spin_lock(&card->files_lock);
926	list_for_each_entry(mfile, &card->files_list, list) {
927		if (mfile->file == file) {
928			list_del(&mfile->list);
929			spin_lock(&shutdown_lock);
930			list_del(&mfile->shutdown_list);
931			spin_unlock(&shutdown_lock);
932			if (mfile->disconnected_f_op)
933				fops_put(mfile->disconnected_f_op);
934			found = mfile;
935			break;
936		}
937	}
 
 
938	spin_unlock(&card->files_lock);
 
 
 
 
 
939	if (!found) {
940		dev_err(card->dev, "card file remove problem (%p)\n", file);
941		return -ENOENT;
942	}
943	kfree(found);
944	put_device(&card->card_dev);
945	return 0;
946}
947
948EXPORT_SYMBOL(snd_card_file_remove);
949
950#ifdef CONFIG_PM
951/**
952 *  snd_power_wait - wait until the power-state is changed.
953 *  @card: soundcard structure
954 *  @power_state: expected power state
955 *
956 *  Waits until the power-state is changed.
957 *
958 *  Return: Zero if successful, or a negative error code.
959 *
960 *  Note: the power lock must be active before call.
961 */
962int snd_power_wait(struct snd_card *card, unsigned int power_state)
963{
964	wait_queue_t wait;
965	int result = 0;
966
967	/* fastpath */
968	if (snd_power_get_state(card) == power_state)
969		return 0;
970	init_waitqueue_entry(&wait, current);
971	add_wait_queue(&card->power_sleep, &wait);
972	while (1) {
973		if (card->shutdown) {
974			result = -ENODEV;
975			break;
976		}
977		if (snd_power_get_state(card) == power_state)
978			break;
979		set_current_state(TASK_UNINTERRUPTIBLE);
980		snd_power_unlock(card);
981		schedule_timeout(30 * HZ);
982		snd_power_lock(card);
983	}
984	remove_wait_queue(&card->power_sleep, &wait);
985	return result;
986}
987
988EXPORT_SYMBOL(snd_power_wait);
989#endif /* CONFIG_PM */
v3.1
  1/*
  2 *  Initialization routines
  3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  4 *
  5 *
  6 *   This program is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU General Public License as published by
  8 *   the Free Software Foundation; either version 2 of the License, or
  9 *   (at your option) any later version.
 10 *
 11 *   This program is distributed in the hope that it will be useful,
 12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *   GNU General Public License for more details.
 15 *
 16 *   You should have received a copy of the GNU General Public License
 17 *   along with this program; if not, write to the Free Software
 18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19 *
 20 */
 21
 22#include <linux/init.h>
 23#include <linux/sched.h>
 
 
 24#include <linux/file.h>
 25#include <linux/slab.h>
 26#include <linux/time.h>
 27#include <linux/ctype.h>
 28#include <linux/pm.h>
 
 29
 30#include <sound/core.h>
 31#include <sound/control.h>
 32#include <sound/info.h>
 33
 34/* monitor files for graceful shutdown (hotplug) */
 35struct snd_monitor_file {
 36	struct file *file;
 37	const struct file_operations *disconnected_f_op;
 38	struct list_head shutdown_list;	/* still need to shutdown */
 39	struct list_head list;	/* link of monitor files */
 40};
 41
 42static DEFINE_SPINLOCK(shutdown_lock);
 43static LIST_HEAD(shutdown_files);
 44
 45static const struct file_operations snd_shutdown_f_ops;
 46
 47static unsigned int snd_cards_lock;	/* locked for registering/using */
 
 48struct snd_card *snd_cards[SNDRV_CARDS];
 49EXPORT_SYMBOL(snd_cards);
 50
 51static DEFINE_MUTEX(snd_card_mutex);
 52
 53static char *slots[SNDRV_CARDS];
 54module_param_array(slots, charp, NULL, 0444);
 55MODULE_PARM_DESC(slots, "Module names assigned to the slots.");
 56
 57/* return non-zero if the given index is reserved for the given
 58 * module via slots option
 59 */
 60static int module_slot_match(struct module *module, int idx)
 61{
 62	int match = 1;
 63#ifdef MODULE
 64	const char *s1, *s2;
 65
 66	if (!module || !module->name || !slots[idx])
 67		return 0;
 68
 69	s1 = module->name;
 70	s2 = slots[idx];
 71	if (*s2 == '!') {
 72		match = 0; /* negative match */
 73		s2++;
 74	}
 75	/* compare module name strings
 76	 * hyphens are handled as equivalent with underscore
 77	 */
 78	for (;;) {
 79		char c1 = *s1++;
 80		char c2 = *s2++;
 81		if (c1 == '-')
 82			c1 = '_';
 83		if (c2 == '-')
 84			c2 = '_';
 85		if (c1 != c2)
 86			return !match;
 87		if (!c1)
 88			break;
 89	}
 90#endif /* MODULE */
 91	return match;
 92}
 93
 94#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
 95int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);
 96EXPORT_SYMBOL(snd_mixer_oss_notify_callback);
 97#endif
 98
 99#ifdef CONFIG_PROC_FS
100static void snd_card_id_read(struct snd_info_entry *entry,
101			     struct snd_info_buffer *buffer)
102{
103	snd_iprintf(buffer, "%s\n", entry->card->id);
104}
105
106static inline int init_info_for_card(struct snd_card *card)
107{
108	int err;
109	struct snd_info_entry *entry;
110
111	if ((err = snd_info_card_register(card)) < 0) {
112		snd_printd("unable to create card info\n");
113		return err;
114	}
115	if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
116		snd_printd("unable to create card entry\n");
117		return err;
118	}
119	entry->c.text.read = snd_card_id_read;
120	if (snd_info_register(entry) < 0) {
121		snd_info_free_entry(entry);
122		entry = NULL;
123	}
124	card->proc_id = entry;
125	return 0;
126}
127#else /* !CONFIG_PROC_FS */
128#define init_info_for_card(card)
129#endif
130
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131/**
132 *  snd_card_create - create and initialize a soundcard structure
 
133 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
134 *  @xid: card identification (ASCII string)
135 *  @module: top level module for locking
136 *  @extra_size: allocate this extra size after the main soundcard structure
137 *  @card_ret: the pointer to store the created card instance
138 *
139 *  Creates and initializes a soundcard structure.
140 *
141 *  The function allocates snd_card instance via kzalloc with the given
142 *  space for the driver to use freely.  The allocated struct is stored
143 *  in the given card_ret pointer.
144 *
145 *  Returns zero if successful or a negative error code.
146 */
147int snd_card_create(int idx, const char *xid,
148		    struct module *module, int extra_size,
149		    struct snd_card **card_ret)
150{
151	struct snd_card *card;
152	int err, idx2;
153
154	if (snd_BUG_ON(!card_ret))
155		return -EINVAL;
156	*card_ret = NULL;
157
158	if (extra_size < 0)
159		extra_size = 0;
160	card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
161	if (!card)
162		return -ENOMEM;
 
 
163	if (xid)
164		strlcpy(card->id, xid, sizeof(card->id));
165	err = 0;
166	mutex_lock(&snd_card_mutex);
167	if (idx < 0) {
168		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
169			/* idx == -1 == 0xffff means: take any free slot */
170			if (~snd_cards_lock & idx & 1<<idx2) {
171				if (module_slot_match(module, idx2)) {
172					idx = idx2;
173					break;
174				}
175			}
176	}
177	if (idx < 0) {
178		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
179			/* idx == -1 == 0xffff means: take any free slot */
180			if (~snd_cards_lock & idx & 1<<idx2) {
181				if (!slots[idx2] || !*slots[idx2]) {
182					idx = idx2;
183					break;
184				}
185			}
186	}
187	if (idx < 0)
188		err = -ENODEV;
189	else if (idx < snd_ecards_limit) {
190		if (snd_cards_lock & (1 << idx))
191			err = -EBUSY;	/* invalid */
192	} else if (idx >= SNDRV_CARDS)
193		err = -ENODEV;
194	if (err < 0) {
195		mutex_unlock(&snd_card_mutex);
196		snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i), error: %d\n",
197			 idx, snd_ecards_limit - 1, err);
198		goto __error;
 
199	}
200	snd_cards_lock |= 1 << idx;		/* lock it */
201	if (idx >= snd_ecards_limit)
202		snd_ecards_limit = idx + 1; /* increase the limit */
203	mutex_unlock(&snd_card_mutex);
 
204	card->number = idx;
205	card->module = module;
206	INIT_LIST_HEAD(&card->devices);
207	init_rwsem(&card->controls_rwsem);
208	rwlock_init(&card->ctl_files_rwlock);
209	INIT_LIST_HEAD(&card->controls);
210	INIT_LIST_HEAD(&card->ctl_files);
211	spin_lock_init(&card->files_lock);
212	INIT_LIST_HEAD(&card->files_list);
213	init_waitqueue_head(&card->shutdown_sleep);
214#ifdef CONFIG_PM
215	mutex_init(&card->power_lock);
216	init_waitqueue_head(&card->power_sleep);
217#endif
 
 
 
 
 
 
 
 
 
 
218	/* the control interface cannot be accessed from the user space until */
219	/* snd_cards_bitmask and snd_cards are set with snd_card_register */
220	err = snd_ctl_create(card);
221	if (err < 0) {
222		snd_printk(KERN_ERR "unable to register control minors\n");
223		goto __error;
224	}
225	err = snd_info_card_create(card);
226	if (err < 0) {
227		snd_printk(KERN_ERR "unable to create card info\n");
228		goto __error_ctl;
229	}
230	if (extra_size > 0)
231		card->private_data = (char *)card + sizeof(struct snd_card);
232	*card_ret = card;
233	return 0;
234
235      __error_ctl:
236	snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
237      __error:
238	kfree(card);
239  	return err;
240}
241EXPORT_SYMBOL(snd_card_create);
242
243/* return non-zero if a card is already locked */
244int snd_card_locked(int card)
245{
246	int locked;
247
248	mutex_lock(&snd_card_mutex);
249	locked = snd_cards_lock & (1 << card);
250	mutex_unlock(&snd_card_mutex);
251	return locked;
252}
253
254static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
255{
256	return -ENODEV;
257}
258
259static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
260				   size_t count, loff_t *offset)
261{
262	return -ENODEV;
263}
264
265static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
266				    size_t count, loff_t *offset)
267{
268	return -ENODEV;
269}
270
271static int snd_disconnect_release(struct inode *inode, struct file *file)
272{
273	struct snd_monitor_file *df = NULL, *_df;
274
275	spin_lock(&shutdown_lock);
276	list_for_each_entry(_df, &shutdown_files, shutdown_list) {
277		if (_df->file == file) {
278			df = _df;
279			list_del_init(&df->shutdown_list);
280			break;
281		}
282	}
283	spin_unlock(&shutdown_lock);
284
285	if (likely(df)) {
286		if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync)
287			df->disconnected_f_op->fasync(-1, file, 0);
288		return df->disconnected_f_op->release(inode, file);
289	}
290
291	panic("%s(%p, %p) failed!", __func__, inode, file);
292}
293
294static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
295{
296	return POLLERR | POLLNVAL;
297}
298
299static long snd_disconnect_ioctl(struct file *file,
300				 unsigned int cmd, unsigned long arg)
301{
302	return -ENODEV;
303}
304
305static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
306{
307	return -ENODEV;
308}
309
310static int snd_disconnect_fasync(int fd, struct file *file, int on)
311{
312	return -ENODEV;
313}
314
315static const struct file_operations snd_shutdown_f_ops =
316{
317	.owner = 	THIS_MODULE,
318	.llseek =	snd_disconnect_llseek,
319	.read = 	snd_disconnect_read,
320	.write =	snd_disconnect_write,
321	.release =	snd_disconnect_release,
322	.poll =		snd_disconnect_poll,
323	.unlocked_ioctl = snd_disconnect_ioctl,
324#ifdef CONFIG_COMPAT
325	.compat_ioctl = snd_disconnect_ioctl,
326#endif
327	.mmap =		snd_disconnect_mmap,
328	.fasync =	snd_disconnect_fasync
329};
330
331/**
332 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
333 *  @card: soundcard structure
334 *
335 *  Disconnects all APIs from the file-operations (user space).
336 *
337 *  Returns zero, otherwise a negative error code.
338 *
339 *  Note: The current implementation replaces all active file->f_op with special
340 *        dummy file operations (they do nothing except release).
341 */
342int snd_card_disconnect(struct snd_card *card)
343{
344	struct snd_monitor_file *mfile;
345	int err;
346
347	if (!card)
348		return -EINVAL;
349
350	spin_lock(&card->files_lock);
351	if (card->shutdown) {
352		spin_unlock(&card->files_lock);
353		return 0;
354	}
355	card->shutdown = 1;
356	spin_unlock(&card->files_lock);
357
358	/* phase 1: disable fops (user space) operations for ALSA API */
359	mutex_lock(&snd_card_mutex);
360	snd_cards[card->number] = NULL;
361	snd_cards_lock &= ~(1 << card->number);
362	mutex_unlock(&snd_card_mutex);
363	
364	/* phase 2: replace file->f_op with special dummy operations */
365	
366	spin_lock(&card->files_lock);
367	list_for_each_entry(mfile, &card->files_list, list) {
368		/* it's critical part, use endless loop */
369		/* we have no room to fail */
370		mfile->disconnected_f_op = mfile->file->f_op;
371
372		spin_lock(&shutdown_lock);
373		list_add(&mfile->shutdown_list, &shutdown_files);
374		spin_unlock(&shutdown_lock);
375
376		mfile->file->f_op = &snd_shutdown_f_ops;
377		fops_get(mfile->file->f_op);
378	}
379	spin_unlock(&card->files_lock);	
380
381	/* phase 3: notify all connected devices about disconnection */
382	/* at this point, they cannot respond to any calls except release() */
383
384#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
385	if (snd_mixer_oss_notify_callback)
386		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
387#endif
388
389	/* notify all devices that we are disconnected */
390	err = snd_device_disconnect_all(card);
391	if (err < 0)
392		snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);
393
394	snd_info_card_disconnect(card);
395	if (card->card_dev) {
396		device_unregister(card->card_dev);
397		card->card_dev = NULL;
398	}
399#ifdef CONFIG_PM
400	wake_up(&card->power_sleep);
401#endif
402	return 0;	
403}
404
405EXPORT_SYMBOL(snd_card_disconnect);
406
407/**
408 *  snd_card_free - frees given soundcard structure
409 *  @card: soundcard structure
410 *
411 *  This function releases the soundcard structure and the all assigned
412 *  devices automatically.  That is, you don't have to release the devices
413 *  by yourself.
414 *
415 *  Returns zero. Frees all associated devices and frees the control
416 *  interface associated to given soundcard.
417 */
418static int snd_card_do_free(struct snd_card *card)
419{
420#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
421	if (snd_mixer_oss_notify_callback)
422		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
423#endif
424	if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
425		snd_printk(KERN_ERR "unable to free all devices (pre)\n");
426		/* Fatal, but this situation should never occur */
427	}
428	if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
429		snd_printk(KERN_ERR "unable to free all devices (normal)\n");
430		/* Fatal, but this situation should never occur */
431	}
432	if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
433		snd_printk(KERN_ERR "unable to free all devices (post)\n");
434		/* Fatal, but this situation should never occur */
435	}
436	if (card->private_free)
437		card->private_free(card);
438	snd_info_free_entry(card->proc_id);
439	if (snd_info_card_free(card) < 0) {
440		snd_printk(KERN_WARNING "unable to free card info\n");
441		/* Not fatal error */
442	}
 
 
443	kfree(card);
444	return 0;
445}
446
447int snd_card_free_when_closed(struct snd_card *card)
448{
449	int free_now = 0;
450	int ret = snd_card_disconnect(card);
451	if (ret)
452		return ret;
453
454	spin_lock(&card->files_lock);
455	if (list_empty(&card->files_list))
456		free_now = 1;
457	else
458		card->free_on_last_close = 1;
459	spin_unlock(&card->files_lock);
460
461	if (free_now)
462		snd_card_do_free(card);
463	return 0;
464}
465
466EXPORT_SYMBOL(snd_card_free_when_closed);
467
468int snd_card_free(struct snd_card *card)
469{
470	int ret = snd_card_disconnect(card);
 
 
 
 
 
471	if (ret)
472		return ret;
473
474	/* wait, until all devices are ready for the free operation */
475	wait_event(card->shutdown_sleep, list_empty(&card->files_list));
476	snd_card_do_free(card);
477	return 0;
478}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
479
480EXPORT_SYMBOL(snd_card_free);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
481
482static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
 
 
 
 
483{
484	int i, len, idx_flag = 0, loops = SNDRV_CARDS;
485	const char *spos, *src;
486	char *id;
487	
488	if (nid == NULL) {
489		id = card->shortname;
490		spos = src = id;
491		while (*id != '\0') {
492			if (*id == ' ')
493				spos = id + 1;
494			id++;
495		}
496	} else {
497		spos = src = nid;
498	}
499	id = card->id;
500	while (*spos != '\0' && !isalnum(*spos))
501		spos++;
502	if (isdigit(*spos))
503		*id++ = isalpha(src[0]) ? src[0] : 'D';
504	while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
505		if (isalnum(*spos))
506			*id++ = *spos;
507		spos++;
508	}
509	*id = '\0';
510
511	id = card->id;
512	
513	if (*id == '\0')
 
 
514		strcpy(id, "Default");
 
 
515
516	while (1) {
517	      	if (loops-- == 0) {
518			snd_printk(KERN_ERR "unable to set card id (%s)\n", id);
519      			strcpy(card->id, card->proc_root->name);
520      			return;
521      		}
522	      	if (!snd_info_check_reserved_words(id))
523      			goto __change;
524		for (i = 0; i < snd_ecards_limit; i++) {
525			if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
526				goto __change;
527		}
528		break;
529
530	      __change:
531		len = strlen(id);
532		if (idx_flag) {
533			if (id[len-1] != '9')
534				id[len-1]++;
535			else
536				id[len-1] = 'A';
537		} else if ((size_t)len <= sizeof(card->id) - 3) {
538			strcat(id, "_1");
539			idx_flag++;
540		} else {
541			spos = id + len - 2;
542			if ((size_t)len <= sizeof(card->id) - 2)
543				spos++;
544			*(char *)spos++ = '_';
545			*(char *)spos++ = '1';
546			*(char *)spos++ = '\0';
547			idx_flag++;
548		}
549	}
 
 
 
 
 
 
 
 
 
550}
551
552/**
553 *  snd_card_set_id - set card identification name
554 *  @card: soundcard structure
555 *  @nid: new identification string
556 *
557 *  This function sets the card identification and checks for name
558 *  collisions.
559 */
560void snd_card_set_id(struct snd_card *card, const char *nid)
561{
562	/* check if user specified own card->id */
563	if (card->id[0] != '\0')
564		return;
565	mutex_lock(&snd_card_mutex);
566	snd_card_set_id_no_lock(card, nid);
567	mutex_unlock(&snd_card_mutex);
568}
569EXPORT_SYMBOL(snd_card_set_id);
570
571static ssize_t
572card_id_show_attr(struct device *dev,
573		  struct device_attribute *attr, char *buf)
574{
575	struct snd_card *card = dev_get_drvdata(dev);
576	return snprintf(buf, PAGE_SIZE, "%s\n", card ? card->id : "(null)");
577}
578
579static ssize_t
580card_id_store_attr(struct device *dev, struct device_attribute *attr,
581		   const char *buf, size_t count)
582{
583	struct snd_card *card = dev_get_drvdata(dev);
584	char buf1[sizeof(card->id)];
585	size_t copy = count > sizeof(card->id) - 1 ?
586					sizeof(card->id) - 1 : count;
587	size_t idx;
588	int c;
589
590	for (idx = 0; idx < copy; idx++) {
591		c = buf[idx];
592		if (!isalnum(c) && c != '_' && c != '-')
593			return -EINVAL;
594	}
595	memcpy(buf1, buf, copy);
596	buf1[copy] = '\0';
597	mutex_lock(&snd_card_mutex);
598	if (!snd_info_check_reserved_words(buf1)) {
599	     __exist:
600		mutex_unlock(&snd_card_mutex);
601		return -EEXIST;
602	}
603	for (idx = 0; idx < snd_ecards_limit; idx++) {
604		if (snd_cards[idx] && !strcmp(snd_cards[idx]->id, buf1)) {
605			if (card == snd_cards[idx])
606				goto __ok;
607			else
608				goto __exist;
609		}
610	}
611	strcpy(card->id, buf1);
612	snd_info_card_id_change(card);
613__ok:
614	mutex_unlock(&snd_card_mutex);
615
616	return count;
617}
618
619static struct device_attribute card_id_attrs =
620	__ATTR(id, S_IRUGO | S_IWUSR, card_id_show_attr, card_id_store_attr);
621
622static ssize_t
623card_number_show_attr(struct device *dev,
624		     struct device_attribute *attr, char *buf)
625{
626	struct snd_card *card = dev_get_drvdata(dev);
627	return snprintf(buf, PAGE_SIZE, "%i\n", card ? card->number : -1);
628}
629
630static struct device_attribute card_number_attrs =
631	__ATTR(number, S_IRUGO, card_number_show_attr, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
632
633/**
634 *  snd_card_register - register the soundcard
635 *  @card: soundcard structure
636 *
637 *  This function registers all the devices assigned to the soundcard.
638 *  Until calling this, the ALSA control interface is blocked from the
639 *  external accesses.  Thus, you should call this function at the end
640 *  of the initialization of the card.
641 *
642 *  Returns zero otherwise a negative error code if the registration failed.
643 */
644int snd_card_register(struct snd_card *card)
645{
646	int err;
647
648	if (snd_BUG_ON(!card))
649		return -EINVAL;
650
651	if (!card->card_dev) {
652		card->card_dev = device_create(sound_class, card->dev,
653					       MKDEV(0, 0), card,
654					       "card%i", card->number);
655		if (IS_ERR(card->card_dev))
656			card->card_dev = NULL;
657	}
658
659	if ((err = snd_device_register_all(card)) < 0)
660		return err;
661	mutex_lock(&snd_card_mutex);
662	if (snd_cards[card->number]) {
663		/* already registered */
664		mutex_unlock(&snd_card_mutex);
665		return 0;
666	}
667	snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
 
 
 
 
 
 
 
 
 
 
 
668	snd_cards[card->number] = card;
669	mutex_unlock(&snd_card_mutex);
670	init_info_for_card(card);
671#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
672	if (snd_mixer_oss_notify_callback)
673		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
674#endif
675	if (card->card_dev) {
676		err = device_create_file(card->card_dev, &card_id_attrs);
677		if (err < 0)
678			return err;
679		err = device_create_file(card->card_dev, &card_number_attrs);
680		if (err < 0)
681			return err;
682	}
683
684	return 0;
685}
686
687EXPORT_SYMBOL(snd_card_register);
688
689#ifdef CONFIG_PROC_FS
690static struct snd_info_entry *snd_card_info_entry;
691
692static void snd_card_info_read(struct snd_info_entry *entry,
693			       struct snd_info_buffer *buffer)
694{
695	int idx, count;
696	struct snd_card *card;
697
698	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
699		mutex_lock(&snd_card_mutex);
700		if ((card = snd_cards[idx]) != NULL) {
701			count++;
702			snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n",
703					idx,
704					card->id,
705					card->driver,
706					card->shortname);
707			snd_iprintf(buffer, "                      %s\n",
708					card->longname);
709		}
710		mutex_unlock(&snd_card_mutex);
711	}
712	if (!count)
713		snd_iprintf(buffer, "--- no soundcards ---\n");
714}
715
716#ifdef CONFIG_SND_OSSEMUL
717
718void snd_card_info_read_oss(struct snd_info_buffer *buffer)
719{
720	int idx, count;
721	struct snd_card *card;
722
723	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
724		mutex_lock(&snd_card_mutex);
725		if ((card = snd_cards[idx]) != NULL) {
726			count++;
727			snd_iprintf(buffer, "%s\n", card->longname);
728		}
729		mutex_unlock(&snd_card_mutex);
730	}
731	if (!count) {
732		snd_iprintf(buffer, "--- no soundcards ---\n");
733	}
734}
735
736#endif
737
738#ifdef MODULE
739static struct snd_info_entry *snd_card_module_info_entry;
740static void snd_card_module_info_read(struct snd_info_entry *entry,
741				      struct snd_info_buffer *buffer)
742{
743	int idx;
744	struct snd_card *card;
745
746	for (idx = 0; idx < SNDRV_CARDS; idx++) {
747		mutex_lock(&snd_card_mutex);
748		if ((card = snd_cards[idx]) != NULL)
749			snd_iprintf(buffer, "%2i %s\n",
750				    idx, card->module->name);
751		mutex_unlock(&snd_card_mutex);
752	}
753}
754#endif
755
756int __init snd_card_info_init(void)
757{
758	struct snd_info_entry *entry;
759
760	entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
761	if (! entry)
762		return -ENOMEM;
763	entry->c.text.read = snd_card_info_read;
764	if (snd_info_register(entry) < 0) {
765		snd_info_free_entry(entry);
766		return -ENOMEM;
767	}
768	snd_card_info_entry = entry;
769
770#ifdef MODULE
771	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
772	if (entry) {
773		entry->c.text.read = snd_card_module_info_read;
774		if (snd_info_register(entry) < 0)
775			snd_info_free_entry(entry);
776		else
777			snd_card_module_info_entry = entry;
778	}
779#endif
780
781	return 0;
782}
783
784int __exit snd_card_info_done(void)
785{
786	snd_info_free_entry(snd_card_info_entry);
787#ifdef MODULE
788	snd_info_free_entry(snd_card_module_info_entry);
789#endif
790	return 0;
791}
792
793#endif /* CONFIG_PROC_FS */
794
795/**
796 *  snd_component_add - add a component string
797 *  @card: soundcard structure
798 *  @component: the component id string
799 *
800 *  This function adds the component id string to the supported list.
801 *  The component can be referred from the alsa-lib.
802 *
803 *  Returns zero otherwise a negative error code.
804 */
805  
806int snd_component_add(struct snd_card *card, const char *component)
807{
808	char *ptr;
809	int len = strlen(component);
810
811	ptr = strstr(card->components, component);
812	if (ptr != NULL) {
813		if (ptr[len] == '\0' || ptr[len] == ' ')	/* already there */
814			return 1;
815	}
816	if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
817		snd_BUG();
818		return -ENOMEM;
819	}
820	if (card->components[0] != '\0')
821		strcat(card->components, " ");
822	strcat(card->components, component);
823	return 0;
824}
825
826EXPORT_SYMBOL(snd_component_add);
827
828/**
829 *  snd_card_file_add - add the file to the file list of the card
830 *  @card: soundcard structure
831 *  @file: file pointer
832 *
833 *  This function adds the file to the file linked-list of the card.
834 *  This linked-list is used to keep tracking the connection state,
835 *  and to avoid the release of busy resources by hotplug.
836 *
837 *  Returns zero or a negative error code.
838 */
839int snd_card_file_add(struct snd_card *card, struct file *file)
840{
841	struct snd_monitor_file *mfile;
842
843	mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
844	if (mfile == NULL)
845		return -ENOMEM;
846	mfile->file = file;
847	mfile->disconnected_f_op = NULL;
848	INIT_LIST_HEAD(&mfile->shutdown_list);
849	spin_lock(&card->files_lock);
850	if (card->shutdown) {
851		spin_unlock(&card->files_lock);
852		kfree(mfile);
853		return -ENODEV;
854	}
855	list_add(&mfile->list, &card->files_list);
 
856	spin_unlock(&card->files_lock);
857	return 0;
858}
859
860EXPORT_SYMBOL(snd_card_file_add);
861
862/**
863 *  snd_card_file_remove - remove the file from the file list
864 *  @card: soundcard structure
865 *  @file: file pointer
866 *
867 *  This function removes the file formerly added to the card via
868 *  snd_card_file_add() function.
869 *  If all files are removed and snd_card_free_when_closed() was
870 *  called beforehand, it processes the pending release of
871 *  resources.
872 *
873 *  Returns zero or a negative error code.
874 */
875int snd_card_file_remove(struct snd_card *card, struct file *file)
876{
877	struct snd_monitor_file *mfile, *found = NULL;
878	int last_close = 0;
879
880	spin_lock(&card->files_lock);
881	list_for_each_entry(mfile, &card->files_list, list) {
882		if (mfile->file == file) {
883			list_del(&mfile->list);
884			spin_lock(&shutdown_lock);
885			list_del(&mfile->shutdown_list);
886			spin_unlock(&shutdown_lock);
887			if (mfile->disconnected_f_op)
888				fops_put(mfile->disconnected_f_op);
889			found = mfile;
890			break;
891		}
892	}
893	if (list_empty(&card->files_list))
894		last_close = 1;
895	spin_unlock(&card->files_lock);
896	if (last_close) {
897		wake_up(&card->shutdown_sleep);
898		if (card->free_on_last_close)
899			snd_card_do_free(card);
900	}
901	if (!found) {
902		snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
903		return -ENOENT;
904	}
905	kfree(found);
 
906	return 0;
907}
908
909EXPORT_SYMBOL(snd_card_file_remove);
910
911#ifdef CONFIG_PM
912/**
913 *  snd_power_wait - wait until the power-state is changed.
914 *  @card: soundcard structure
915 *  @power_state: expected power state
916 *
917 *  Waits until the power-state is changed.
 
 
918 *
919 *  Note: the power lock must be active before call.
920 */
921int snd_power_wait(struct snd_card *card, unsigned int power_state)
922{
923	wait_queue_t wait;
924	int result = 0;
925
926	/* fastpath */
927	if (snd_power_get_state(card) == power_state)
928		return 0;
929	init_waitqueue_entry(&wait, current);
930	add_wait_queue(&card->power_sleep, &wait);
931	while (1) {
932		if (card->shutdown) {
933			result = -ENODEV;
934			break;
935		}
936		if (snd_power_get_state(card) == power_state)
937			break;
938		set_current_state(TASK_UNINTERRUPTIBLE);
939		snd_power_unlock(card);
940		schedule_timeout(30 * HZ);
941		snd_power_lock(card);
942	}
943	remove_wait_queue(&card->power_sleep, &wait);
944	return result;
945}
946
947EXPORT_SYMBOL(snd_power_wait);
948#endif /* CONFIG_PM */