/* * Initialization routines * Copyright (c) by Jaroslav Kysela * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include #include #include #include #include #include #include #include #include #include #include #include struct snd_shutdown_f_ops { struct file_operations f_ops; struct snd_shutdown_f_ops *next; }; unsigned int snd_cards_lock = 0; /* locked for registering/using */ struct snd_card *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL}; DEFINE_RWLOCK(snd_card_rwlock); #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag); #endif #ifdef CONFIG_PROC_FS static void snd_card_id_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer) { snd_iprintf(buffer, "%s\n", entry->card->id); } static inline int init_info_for_card(struct snd_card *card) { int err; struct snd_info_entry *entry; if ((err = snd_info_card_register(card)) < 0) { snd_printd("unable to create card info\n"); return err; } if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) { snd_printd("unable to create card entry\n"); return err; } entry->c.text.read_size = PAGE_SIZE; entry->c.text.read = snd_card_id_read; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); entry = NULL; } card->proc_id = entry; return 0; } #else /* !CONFIG_PROC_FS */ #define init_info_for_card(card) #endif static void snd_card_free_thread(void * __card); /** * snd_card_new - create and initialize a soundcard structure * @idx: card index (address) [0 ... (SNDRV_CARDS-1)] * @xid: card identification (ASCII string) * @module: top level module for locking * @extra_size: allocate this extra size after the main soundcard structure * * Creates and initializes a soundcard structure. * * Returns kmallocated snd_card structure. Creates the ALSA control interface * (which is blocked until snd_card_register function is called). */ struct snd_card *snd_card_new(int idx, const char *xid, struct module *module, int extra_size) { struct snd_card *card; int err; if (extra_size < 0) extra_size = 0; card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL); if (card == NULL) return NULL; if (xid) { if (!snd_info_check_reserved_words(xid)) goto __error; strlcpy(card->id, xid, sizeof(card->id)); } err = 0; write_lock(&snd_card_rwlock); if (idx < 0) { int idx2; for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++) if (~snd_cards_lock & idx & 1<= snd_ecards_limit) snd_ecards_limit = idx + 1; break; } } else if (idx < snd_ecards_limit) { if (snd_cards_lock & (1 << idx)) err = -ENODEV; /* invalid */ } else if (idx < SNDRV_CARDS) snd_ecards_limit = idx + 1; /* increase the limit */ else err = -ENODEV; if (idx < 0 || err < 0) { write_unlock(&snd_card_rwlock); snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1); goto __error; } snd_cards_lock |= 1 << idx; /* lock it */ write_unlock(&snd_card_rwlock); card->number = idx; card->module = module; INIT_LIST_HEAD(&card->devices); init_rwsem(&card->controls_rwsem); rwlock_init(&card->ctl_files_rwlock); INIT_LIST_HEAD(&card->controls); INIT_LIST_HEAD(&card->ctl_files); spin_lock_init(&card->files_lock); init_waitqueue_head(&card->shutdown_sleep); INIT_WORK(&card->free_workq, snd_card_free_thread, card); #ifdef CONFIG_PM init_MUTEX(&card->power_lock); init_waitqueue_head(&card->power_sleep); #endif /* the control interface cannot be accessed from the user space until */ /* snd_cards_bitmask and snd_cards are set with snd_card_register */ if ((err = snd_ctl_create(card)) < 0) { snd_printd("unable to register control minors\n"); goto __error; } if ((err = snd_info_card_create(card)) < 0) { snd_printd("unable to create card info\n"); goto __error_ctl; } if (extra_size > 0) card->private_data = (char *)card + sizeof(struct snd_card); return card; __error_ctl: snd_device_free_all(card, SNDRV_DEV_CMD_PRE); __error: kfree(card); return NULL; } static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait) { return POLLERR | POLLNVAL; } /** * snd_card_disconnect - disconnect all APIs from the file-operations (user space) * @card: soundcard structure * * Disconnects all APIs from the file-operations (user space). * * Returns zero, otherwise a negative error code. * * Note: The current implementation replaces all active file->f_op with special * dummy file operations (they do nothing except release). */ int snd_card_disconnect(struct snd_card *card) { struct snd_monitor_file *mfile; struct file *file; struct snd_shutdown_f_ops *s_f_ops; struct file_operations *f_ops, *old_f_ops; int err; spin_lock(&card->files_lock); if (card->shutdown) { spin_unlock(&card->files_lock); return 0; } card->shutdown = 1; spin_unlock(&card->files_lock); /* phase 1: disable fops (user space) operations for ALSA API */ write_lock(&snd_card_rwlock); snd_cards[card->number] = NULL; write_unlock(&snd_card_rwlock); /* phase 2: replace file->f_op with special dummy operations */ spin_lock(&card->files_lock); mfile = card->files; while (mfile) { file = mfile->file; /* it's critical part, use endless loop */ /* we have no room to fail */ s_f_ops = kmalloc(sizeof(struct snd_shutdown_f_ops), GFP_ATOMIC); if (s_f_ops == NULL) panic("Atomic allocation failed for snd_shutdown_f_ops!"); f_ops = &s_f_ops->f_ops; memset(f_ops, 0, sizeof(*f_ops)); f_ops->owner = file->f_op->owner; f_ops->release = file->f_op->release; f_ops->poll = snd_disconnect_poll; s_f_ops->next = card->s_f_ops; card->s_f_ops = s_f_ops; f_ops = fops_get(f_ops); old_f_ops = file->f_op; file->f_op = f_ops; /* must be atomic */ fops_put(old_f_ops); mfile = mfile->next; } spin_unlock(&card->files_lock); /* phase 3: notify all connected devices about disconnection */ /* at this point, they cannot respond to any calls except release() */ #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) if (snd_mixer_oss_notify_callback) snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT); #endif /* notify all devices that we are disconnected */ err = snd_device_disconnect_all(card); if (err < 0) snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number); return 0; } /** * snd_card_free - frees given soundcard structure * @card: soundcard structure * * This function releases the soundcard structure and the all assigned * devices automatically. That is, you don't have to release the devices * by yourself. * * Returns zero. Frees all associated devices and frees the control * interface associated to given soundcard. */ int snd_card_free(struct snd_card *card) { struct snd_shutdown_f_ops *s_f_ops; if (card == NULL) return -EINVAL; write_lock(&snd_card_rwlock); snd_cards[card->number] = NULL; write_unlock(&snd_card_rwlock); #ifdef CONFIG_PM wake_up(&card->power_sleep); #endif /* wait, until all devices are ready for the free operation */ wait_event(card->shutdown_sleep, card->files == NULL); #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) if (snd_mixer_oss_notify_callback) snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE); #endif if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) { snd_printk(KERN_ERR "unable to free all devices (pre)\n"); /* Fatal, but this situation should never occur */ } if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) { snd_printk(KERN_ERR "unable to free all devices (normal)\n"); /* Fatal, but this situation should never occur */ } if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) { snd_printk(KERN_ERR "unable to free all devices (post)\n"); /* Fatal, but this situation should never occur */ } if (card->private_free) card->private_free(card); snd_info_unregister(card->proc_id); if (snd_info_card_free(card) < 0) { snd_printk(KERN_WARNING "unable to free card info\n"); /* Not fatal error */ } while (card->s_f_ops) { s_f_ops = card->s_f_ops; card->s_f_ops = s_f_ops->next; kfree(s_f_ops); } write_lock(&snd_card_rwlock); snd_cards_lock &= ~(1 << card->number); write_unlock(&snd_card_rwlock); kfree(card); return 0; } static void snd_card_free_thread(void * __card) { struct snd_card *card = __card; struct module * module = card->module; if (!try_module_get(module)) { snd_printk(KERN_ERR "unable to lock toplevel module for card %i in free thread\n", card->number); module = NULL; } snd_card_free(card); module_put(module); } /** * snd_card_free_in_thread - call snd_card_free() in thread * @card: soundcard structure * * This function schedules the call of snd_card_free() function in a * work queue. When all devices are released (non-busy), the work * is woken up and calls snd_card_free(). * * When a card can be disconnected at any time by hotplug service, * this function should be used in disconnect (or detach) callback * instead of calling snd_card_free() directly. * * Returns - zero otherwise a negative error code if the start of thread failed. */ int snd_card_free_in_thread(struct snd_card *card) { if (card->files == NULL) { snd_card_free(card); return 0; } if (schedule_work(&card->free_workq)) return 0; snd_printk(KERN_ERR "schedule_work() failed in snd_card_free_in_thread for card %i\n", card->number); /* try to free the structure immediately */ snd_card_free(card); return -EFAULT; } static void choose_default_id(struct snd_card *card) { int i, len, idx_flag = 0, loops = SNDRV_CARDS; char *id, *spos; id = spos = card->shortname; while (*id != '\0') { if (*id == ' ') spos = id + 1; id++; } id = card->id; while (*spos != '\0' && !isalnum(*spos)) spos++; if (isdigit(*spos)) *id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D'; while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) { if (isalnum(*spos)) *id++ = *spos; spos++; } *id = '\0'; id = card->id; if (*id == '\0') strcpy(id, "default"); while (1) { if (loops-- == 0) { snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id); strcpy(card->id, card->proc_root->name); return; } if (!snd_info_check_reserved_words(id)) goto __change; for (i = 0; i < snd_ecards_limit; i++) { if (snd_cards[i] && !strcmp(snd_cards[i]->id, id)) goto __change; } break; __change: len = strlen(id); if (idx_flag) { if (id[len-1] != '9') id[len-1]++; else id[len-1] = 'A'; } else if ((size_t)len <= sizeof(card->id) - 3) { strcat(id, "_1"); idx_flag++; } else { spos = id + len - 2; if ((size_t)len <= sizeof(card->id) - 2) spos++; *spos++ = '_'; *spos++ = '1'; *spos++ = '\0'; idx_flag++; } } } /** * snd_card_register - register the soundcard * @card: soundcard structure * * This function registers all the devices assigned to the soundcard. * Until calling this, the ALSA control interface is blocked from the * external accesses. Thus, you should call this function at the end * of the initialization of the card. * * Returns zero otherwise a negative error code if the registrain failed. */ int snd_card_register(struct snd_card *card) { int err; snd_assert(card != NULL, return -EINVAL); if ((err = snd_device_register_all(card)) < 0) return err; write_lock(&snd_card_rwlock); if (snd_cards[card->number]) { /* already registered */ write_unlock(&snd_card_rwlock); return 0; } if (card->id[0] == '\0') choose_default_id(card); snd_cards[card->number] = card; write_unlock(&snd_card_rwlock); init_info_for_card(card); #if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE) if (snd_mixer_oss_notify_callback) snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER); #endif return 0; } #ifdef CONFIG_PROC_FS static struct snd_info_entry *snd_card_info_entry = NULL; static void snd_card_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer) { int idx, count; struct snd_card *card; for (idx = count = 0; idx < SNDRV_CARDS; idx++) { read_lock(&snd_card_rwlock); if ((card = snd_cards[idx]) != NULL) { count++; snd_iprintf(buffer, "%2i [%-15s]: %s - %s\n", idx, card->id, card->driver, card->shortname); snd_iprintf(buffer, " %s\n", card->longname); } read_unlock(&snd_card_rwlock); } if (!count) snd_iprintf(buffer, "--- no soundcards ---\n"); } #ifdef CONFIG_SND_OSSEMUL void snd_card_info_read_oss(struct snd_info_buffer *buffer) { int idx, count; struct snd_card *card; for (idx = count = 0; idx < SNDRV_CARDS; idx++) { read_lock(&snd_card_rwlock); if ((card = snd_cards[idx]) != NULL) { count++; snd_iprintf(buffer, "%s\n", card->longname); } read_unlock(&snd_card_rwlock); } if (!count) { snd_iprintf(buffer, "--- no soundcards ---\n"); } } #endif #ifdef MODULE static struct snd_info_entry *snd_card_module_info_entry; static void snd_card_module_info_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer) { int idx; struct snd_card *card; for (idx = 0; idx < SNDRV_CARDS; idx++) { read_lock(&snd_card_rwlock); if ((card = snd_cards[idx]) != NULL) snd_iprintf(buffer, "%2i %s\n", idx, card->module->name); read_unlock(&snd_card_rwlock); } } #endif int __init snd_card_info_init(void) { struct snd_info_entry *entry; entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL); if (! entry) return -ENOMEM; entry->c.text.read_size = PAGE_SIZE; entry->c.text.read = snd_card_info_read; if (snd_info_register(entry) < 0) { snd_info_free_entry(entry); return -ENOMEM; } snd_card_info_entry = entry; #ifdef MODULE entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL); if (entry) { entry->c.text.read_size = PAGE_SIZE; entry->c.text.read = snd_card_module_info_read; if (snd_info_register(entry) < 0) snd_info_free_entry(entry); else snd_card_module_info_entry = entry; } #endif return 0; } int __exit snd_card_info_done(void) { snd_info_unregister(snd_card_info_entry); #ifdef MODULE snd_info_unregister(snd_card_module_info_entry); #endif return 0; } #endif /* CONFIG_PROC_FS */ /** * snd_component_add - add a component string * @card: soundcard structure * @component: the component id string * * This function adds the component id string to the supported list. * The component can be referred from the alsa-lib. * * Returns zero otherwise a negative error code. */ int snd_component_add(struct snd_card *card, const char *component) { char *ptr; int len = strlen(component); ptr = strstr(card->components, component); if (ptr != NULL) { if (ptr[len] == '\0' || ptr[len] == ' ') /* already there */ return 1; } if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) { snd_BUG(); return -ENOMEM; } if (card->components[0] != '\0') strcat(card->components, " "); strcat(card->components, component); return 0; } /** * snd_card_file_add - add the file to the file list of the card * @card: soundcard structure * @file: file pointer * * This function adds the file to the file linked-list of the card. * This linked-list is used to keep tracking the connection state, * and to avoid the release of busy resources by hotplug. * * Returns zero or a negative error code. */ int snd_card_file_add(struct snd_card *card, struct file *file) { struct snd_monitor_file *mfile; mfile = kmalloc(sizeof(*mfile), GFP_KERNEL); if (mfile == NULL) return -ENOMEM; mfile->file = file; mfile->next = NULL; spin_lock(&card->files_lock); if (card->shutdown) { spin_unlock(&card->files_lock); kfree(mfile); return -ENODEV; } mfile->next = card->files; card->files = mfile; spin_unlock(&card->files_lock); return 0; } /** * snd_card_file_remove - remove the file from the file list * @card: soundcard structure * @file: file pointer * * This function removes the file formerly added to the card via * snd_card_file_add() function. * If all files are removed and the release of the card is * scheduled, it will wake up the the thread to call snd_card_free() * (see snd_card_free_in_thread() function). * * Returns zero or a negative error code. */ int snd_card_file_remove(struct snd_card *card, struct file *file) { struct snd_monitor_file *mfile, *pfile = NULL; spin_lock(&card->files_lock); mfile = card->files; while (mfile) { if (mfile->file == file) { if (pfile) pfile->next = mfile->next; else card->files = mfile->next; break; } pfile = mfile; mfile = mfile->next; } spin_unlock(&card->files_lock); if (card->files == NULL) wake_up(&card->shutdown_sleep); if (!mfile) { snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file); return -ENOENT; } kfree(mfile); return 0; } #ifdef CONFIG_PM /** * snd_power_wait - wait until the power-state is changed. * @card: soundcard structure * @power_state: expected power state * @file: file structure for the O_NONBLOCK check (optional) * * Waits until the power-state is changed. * * Note: the power lock must be active before call. */ int snd_power_wait(struct snd_card *card, unsigned int power_state, struct file *file) { wait_queue_t wait; int result = 0; /* fastpath */ if (snd_power_get_state(card) == power_state) return 0; init_waitqueue_entry(&wait, current); add_wait_queue(&card->power_sleep, &wait); while (1) { if (card->shutdown) { result = -ENODEV; break; } if (snd_power_get_state(card) == power_state) break; #if 0 /* block all devices */ if (file && (file->f_flags & O_NONBLOCK)) { result = -EAGAIN; break; } #endif set_current_state(TASK_UNINTERRUPTIBLE); snd_power_unlock(card); schedule_timeout(30 * HZ); snd_power_lock(card); } remove_wait_queue(&card->power_sleep, &wait); return result; } #endif /* CONFIG_PM */