--- zzzz-none-000/linux-3.10.107/sound/core/seq/seq_device.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/sound/core/seq/seq_device.c 2021-02-04 17:41:59.000000000 +0000 @@ -36,6 +36,7 @@ * */ +#include #include #include #include @@ -51,493 +52,227 @@ MODULE_DESCRIPTION("ALSA sequencer device management"); MODULE_LICENSE("GPL"); -/* driver state */ -#define DRIVER_EMPTY 0 -#define DRIVER_LOADED (1<<0) -#define DRIVER_REQUESTED (1<<1) -#define DRIVER_LOCKED (1<<2) - -struct ops_list { - char id[ID_LEN]; /* driver id */ - int driver; /* driver state */ - int used; /* reference counter */ - int argsize; /* argument size */ - - /* operators */ - struct snd_seq_dev_ops ops; - - /* registered devices */ - struct list_head dev_list; /* list of devices */ - int num_devices; /* number of associated devices */ - int num_init_devices; /* number of initialized devices */ - struct mutex reg_mutex; - - struct list_head list; /* next driver */ -}; +/* + * bus definition + */ +static int snd_seq_bus_match(struct device *dev, struct device_driver *drv) +{ + struct snd_seq_device *sdev = to_seq_dev(dev); + struct snd_seq_driver *sdrv = to_seq_drv(drv); + return strcmp(sdrv->id, sdev->id) == 0 && + sdrv->argsize == sdev->argsize; +} -static LIST_HEAD(opslist); -static int num_ops; -static DEFINE_MUTEX(ops_mutex); -#ifdef CONFIG_PROC_FS -static struct snd_info_entry *info_entry; -#endif +static struct bus_type snd_seq_bus_type = { + .name = "snd_seq", + .match = snd_seq_bus_match, +}; /* - * prototypes + * proc interface -- just for compatibility */ -static int snd_seq_device_free(struct snd_seq_device *dev); -static int snd_seq_device_dev_free(struct snd_device *device); -static int snd_seq_device_dev_register(struct snd_device *device); -static int snd_seq_device_dev_disconnect(struct snd_device *device); - -static int init_device(struct snd_seq_device *dev, struct ops_list *ops); -static int free_device(struct snd_seq_device *dev, struct ops_list *ops); -static struct ops_list *find_driver(char *id, int create_if_empty); -static struct ops_list *create_driver(char *id); -static void unlock_driver(struct ops_list *ops); -static void remove_drivers(void); +#ifdef CONFIG_SND_PROC_FS +static struct snd_info_entry *info_entry; -/* - * show all drivers and their status - */ +static int print_dev_info(struct device *dev, void *data) +{ + struct snd_seq_device *sdev = to_seq_dev(dev); + struct snd_info_buffer *buffer = data; + + snd_iprintf(buffer, "snd-%s,%s,%d\n", sdev->id, + dev->driver ? "loaded" : "empty", + dev->driver ? 1 : 0); + return 0; +} -#ifdef CONFIG_PROC_FS static void snd_seq_device_info(struct snd_info_entry *entry, struct snd_info_buffer *buffer) { - struct ops_list *ops; - - mutex_lock(&ops_mutex); - list_for_each_entry(ops, &opslist, list) { - snd_iprintf(buffer, "snd-%s%s%s%s,%d\n", - ops->id, - ops->driver & DRIVER_LOADED ? ",loaded" : (ops->driver == DRIVER_EMPTY ? ",empty" : ""), - ops->driver & DRIVER_REQUESTED ? ",requested" : "", - ops->driver & DRIVER_LOCKED ? ",locked" : "", - ops->num_devices); - } - mutex_unlock(&ops_mutex); + bus_for_each_dev(&snd_seq_bus_type, NULL, buffer, print_dev_info); } #endif - + /* * load all registered drivers (called from seq_clientmgr.c) */ #ifdef CONFIG_MODULES -/* avoid auto-loading during module_init() */ -static int snd_seq_in_init; -void snd_seq_autoload_lock(void) +/* flag to block auto-loading */ +static atomic_t snd_seq_in_init = ATOMIC_INIT(1); /* blocked as default */ + +static int request_seq_drv(struct device *dev, void *data) { - snd_seq_in_init++; + struct snd_seq_device *sdev = to_seq_dev(dev); + + if (!dev->driver) + request_module("snd-%s", sdev->id); + return 0; } -void snd_seq_autoload_unlock(void) +static void autoload_drivers(struct work_struct *work) { - snd_seq_in_init--; + /* avoid reentrance */ + if (atomic_inc_return(&snd_seq_in_init) == 1) + bus_for_each_dev(&snd_seq_bus_type, NULL, NULL, + request_seq_drv); + atomic_dec(&snd_seq_in_init); } -#endif -void snd_seq_device_load_drivers(void) -{ -#ifdef CONFIG_MODULES - struct ops_list *ops; +static DECLARE_WORK(autoload_work, autoload_drivers); - /* Calling request_module during module_init() - * may cause blocking. - */ - if (snd_seq_in_init) - return; - - mutex_lock(&ops_mutex); - list_for_each_entry(ops, &opslist, list) { - if (! (ops->driver & DRIVER_LOADED) && - ! (ops->driver & DRIVER_REQUESTED)) { - ops->used++; - mutex_unlock(&ops_mutex); - ops->driver |= DRIVER_REQUESTED; - request_module("snd-%s", ops->id); - mutex_lock(&ops_mutex); - ops->used--; - } - } - mutex_unlock(&ops_mutex); -#endif +static void queue_autoload_drivers(void) +{ + schedule_work(&autoload_work); } -/* - * register a sequencer device - * card = card info (NULL allowed) - * device = device number (if any) - * id = id of driver - * result = return pointer (NULL allowed if unnecessary) - */ -int snd_seq_device_new(struct snd_card *card, int device, char *id, int argsize, - struct snd_seq_device **result) +void snd_seq_autoload_init(void) { - struct snd_seq_device *dev; - struct ops_list *ops; - int err; - static struct snd_device_ops dops = { - .dev_free = snd_seq_device_dev_free, - .dev_register = snd_seq_device_dev_register, - .dev_disconnect = snd_seq_device_dev_disconnect, - }; - - if (result) - *result = NULL; - - if (snd_BUG_ON(!id)) - return -EINVAL; - - ops = find_driver(id, 1); - if (ops == NULL) - return -ENOMEM; - - dev = kzalloc(sizeof(*dev)*2 + argsize, GFP_KERNEL); - if (dev == NULL) { - unlock_driver(ops); - return -ENOMEM; - } - - /* set up device info */ - dev->card = card; - dev->device = device; - strlcpy(dev->id, id, sizeof(dev->id)); - dev->argsize = argsize; - dev->status = SNDRV_SEQ_DEVICE_FREE; - - /* add this device to the list */ - mutex_lock(&ops->reg_mutex); - list_add_tail(&dev->list, &ops->dev_list); - ops->num_devices++; - mutex_unlock(&ops->reg_mutex); - - unlock_driver(ops); - - if ((err = snd_device_new(card, SNDRV_DEV_SEQUENCER, dev, &dops)) < 0) { - snd_seq_device_free(dev); - return err; - } - - if (result) - *result = dev; - - return 0; + atomic_dec(&snd_seq_in_init); +#ifdef CONFIG_SND_SEQUENCER_MODULE + /* initial autoload only when snd-seq is a module */ + queue_autoload_drivers(); +#endif } +EXPORT_SYMBOL(snd_seq_autoload_init); -/* - * free the existing device - */ -static int snd_seq_device_free(struct snd_seq_device *dev) +void snd_seq_autoload_exit(void) { - struct ops_list *ops; - - if (snd_BUG_ON(!dev)) - return -EINVAL; - - ops = find_driver(dev->id, 0); - if (ops == NULL) - return -ENXIO; - - /* remove the device from the list */ - mutex_lock(&ops->reg_mutex); - list_del(&dev->list); - ops->num_devices--; - mutex_unlock(&ops->reg_mutex); - - free_device(dev, ops); - if (dev->private_free) - dev->private_free(dev); - kfree(dev); - - unlock_driver(ops); - - return 0; + atomic_inc(&snd_seq_in_init); } +EXPORT_SYMBOL(snd_seq_autoload_exit); -static int snd_seq_device_dev_free(struct snd_device *device) +void snd_seq_device_load_drivers(void) { - struct snd_seq_device *dev = device->device_data; - return snd_seq_device_free(dev); + queue_autoload_drivers(); + flush_work(&autoload_work); } +EXPORT_SYMBOL(snd_seq_device_load_drivers); +#else +#define queue_autoload_drivers() /* NOP */ +#endif /* - * register the device + * device management */ -static int snd_seq_device_dev_register(struct snd_device *device) +static int snd_seq_device_dev_free(struct snd_device *device) { struct snd_seq_device *dev = device->device_data; - struct ops_list *ops; - - ops = find_driver(dev->id, 0); - if (ops == NULL) - return -ENOENT; - - /* initialize this device if the corresponding driver was - * already loaded - */ - if (ops->driver & DRIVER_LOADED) - init_device(dev, ops); - unlock_driver(ops); + put_device(&dev->dev); return 0; } -/* - * disconnect the device - */ -static int snd_seq_device_dev_disconnect(struct snd_device *device) +static int snd_seq_device_dev_register(struct snd_device *device) { struct snd_seq_device *dev = device->device_data; - struct ops_list *ops; - - ops = find_driver(dev->id, 0); - if (ops == NULL) - return -ENOENT; - - free_device(dev, ops); + int err; - unlock_driver(ops); + err = device_add(&dev->dev); + if (err < 0) + return err; + if (!dev->dev.driver) + queue_autoload_drivers(); return 0; } -/* - * register device driver - * id = driver id - * entry = driver operators - duplicated to each instance - */ -int snd_seq_device_register_driver(char *id, struct snd_seq_dev_ops *entry, - int argsize) +static int snd_seq_device_dev_disconnect(struct snd_device *device) { - struct ops_list *ops; - struct snd_seq_device *dev; - - if (id == NULL || entry == NULL || - entry->init_device == NULL || entry->free_device == NULL) - return -EINVAL; - - snd_seq_autoload_lock(); - ops = find_driver(id, 1); - if (ops == NULL) { - snd_seq_autoload_unlock(); - return -ENOMEM; - } - if (ops->driver & DRIVER_LOADED) { - snd_printk(KERN_WARNING "driver_register: driver '%s' already exists\n", id); - unlock_driver(ops); - snd_seq_autoload_unlock(); - return -EBUSY; - } - - mutex_lock(&ops->reg_mutex); - /* copy driver operators */ - ops->ops = *entry; - ops->driver |= DRIVER_LOADED; - ops->argsize = argsize; - - /* initialize existing devices if necessary */ - list_for_each_entry(dev, &ops->dev_list, list) { - init_device(dev, ops); - } - mutex_unlock(&ops->reg_mutex); - - unlock_driver(ops); - snd_seq_autoload_unlock(); + struct snd_seq_device *dev = device->device_data; + device_del(&dev->dev); return 0; } - -/* - * create driver record - */ -static struct ops_list * create_driver(char *id) +static void snd_seq_dev_release(struct device *dev) { - struct ops_list *ops; - - ops = kzalloc(sizeof(*ops), GFP_KERNEL); - if (ops == NULL) - return ops; - - /* set up driver entry */ - strlcpy(ops->id, id, sizeof(ops->id)); - mutex_init(&ops->reg_mutex); - /* - * The ->reg_mutex locking rules are per-driver, so we create - * separate per-driver lock classes: - */ - lockdep_set_class(&ops->reg_mutex, (struct lock_class_key *)id); - - ops->driver = DRIVER_EMPTY; - INIT_LIST_HEAD(&ops->dev_list); - /* lock this instance */ - ops->used = 1; - - /* register driver entry */ - mutex_lock(&ops_mutex); - list_add_tail(&ops->list, &opslist); - num_ops++; - mutex_unlock(&ops_mutex); + struct snd_seq_device *sdev = to_seq_dev(dev); - return ops; + if (sdev->private_free) + sdev->private_free(sdev); + kfree(sdev); } - /* - * unregister the specified driver + * register a sequencer device + * card = card info + * device = device number (if any) + * id = id of driver + * result = return pointer (NULL allowed if unnecessary) */ -int snd_seq_device_unregister_driver(char *id) +int snd_seq_device_new(struct snd_card *card, int device, const char *id, + int argsize, struct snd_seq_device **result) { - struct ops_list *ops; struct snd_seq_device *dev; + int err; + static struct snd_device_ops dops = { + .dev_free = snd_seq_device_dev_free, + .dev_register = snd_seq_device_dev_register, + .dev_disconnect = snd_seq_device_dev_disconnect, + }; - ops = find_driver(id, 0); - if (ops == NULL) - return -ENXIO; - if (! (ops->driver & DRIVER_LOADED) || - (ops->driver & DRIVER_LOCKED)) { - snd_printk(KERN_ERR "driver_unregister: cannot unload driver '%s': status=%x\n", - id, ops->driver); - unlock_driver(ops); - return -EBUSY; - } - - /* close and release all devices associated with this driver */ - mutex_lock(&ops->reg_mutex); - ops->driver |= DRIVER_LOCKED; /* do not remove this driver recursively */ - list_for_each_entry(dev, &ops->dev_list, list) { - free_device(dev, ops); - } - - ops->driver = 0; - if (ops->num_init_devices > 0) - snd_printk(KERN_ERR "free_driver: init_devices > 0!! (%d)\n", - ops->num_init_devices); - mutex_unlock(&ops->reg_mutex); - - unlock_driver(ops); - - /* remove empty driver entries */ - remove_drivers(); + if (result) + *result = NULL; - return 0; -} + if (snd_BUG_ON(!id)) + return -EINVAL; + dev = kzalloc(sizeof(*dev) + argsize, GFP_KERNEL); + if (!dev) + return -ENOMEM; -/* - * remove empty driver entries - */ -static void remove_drivers(void) -{ - struct list_head *head; + /* set up device info */ + dev->card = card; + dev->device = device; + dev->id = id; + dev->argsize = argsize; - mutex_lock(&ops_mutex); - head = opslist.next; - while (head != &opslist) { - struct ops_list *ops = list_entry(head, struct ops_list, list); - if (! (ops->driver & DRIVER_LOADED) && - ops->used == 0 && ops->num_devices == 0) { - head = head->next; - list_del(&ops->list); - kfree(ops); - num_ops--; - } else - head = head->next; - } - mutex_unlock(&ops_mutex); -} + device_initialize(&dev->dev); + dev->dev.parent = &card->card_dev; + dev->dev.bus = &snd_seq_bus_type; + dev->dev.release = snd_seq_dev_release; + dev_set_name(&dev->dev, "%s-%d-%d", dev->id, card->number, device); -/* - * initialize the device - call init_device operator - */ -static int init_device(struct snd_seq_device *dev, struct ops_list *ops) -{ - if (! (ops->driver & DRIVER_LOADED)) - return 0; /* driver is not loaded yet */ - if (dev->status != SNDRV_SEQ_DEVICE_FREE) - return 0; /* already initialized */ - if (ops->argsize != dev->argsize) { - snd_printk(KERN_ERR "incompatible device '%s' for plug-in '%s' (%d %d)\n", - dev->name, ops->id, ops->argsize, dev->argsize); - return -EINVAL; - } - if (ops->ops.init_device(dev) >= 0) { - dev->status = SNDRV_SEQ_DEVICE_REGISTERED; - ops->num_init_devices++; - } else { - snd_printk(KERN_ERR "init_device failed: %s: %s\n", - dev->name, dev->id); + /* add this device to the list */ + err = snd_device_new(card, SNDRV_DEV_SEQUENCER, dev, &dops); + if (err < 0) { + put_device(&dev->dev); + return err; } + + if (result) + *result = dev; return 0; } +EXPORT_SYMBOL(snd_seq_device_new); /* - * release the device - call free_device operator + * driver registration */ -static int free_device(struct snd_seq_device *dev, struct ops_list *ops) +int __snd_seq_driver_register(struct snd_seq_driver *drv, struct module *mod) { - int result; - - if (! (ops->driver & DRIVER_LOADED)) - return 0; /* driver is not loaded yet */ - if (dev->status != SNDRV_SEQ_DEVICE_REGISTERED) - return 0; /* not registered */ - if (ops->argsize != dev->argsize) { - snd_printk(KERN_ERR "incompatible device '%s' for plug-in '%s' (%d %d)\n", - dev->name, ops->id, ops->argsize, dev->argsize); + if (WARN_ON(!drv->driver.name || !drv->id)) return -EINVAL; - } - if ((result = ops->ops.free_device(dev)) >= 0 || result == -ENXIO) { - dev->status = SNDRV_SEQ_DEVICE_FREE; - dev->driver_data = NULL; - ops->num_init_devices--; - } else { - snd_printk(KERN_ERR "free_device failed: %s: %s\n", - dev->name, dev->id); - } - - return 0; + drv->driver.bus = &snd_seq_bus_type; + drv->driver.owner = mod; + return driver_register(&drv->driver); } +EXPORT_SYMBOL_GPL(__snd_seq_driver_register); -/* - * find the matching driver with given id - */ -static struct ops_list * find_driver(char *id, int create_if_empty) -{ - struct ops_list *ops; - - mutex_lock(&ops_mutex); - list_for_each_entry(ops, &opslist, list) { - if (strcmp(ops->id, id) == 0) { - ops->used++; - mutex_unlock(&ops_mutex); - return ops; - } - } - mutex_unlock(&ops_mutex); - if (create_if_empty) - return create_driver(id); - return NULL; -} - -static void unlock_driver(struct ops_list *ops) +void snd_seq_driver_unregister(struct snd_seq_driver *drv) { - mutex_lock(&ops_mutex); - ops->used--; - mutex_unlock(&ops_mutex); + driver_unregister(&drv->driver); } - +EXPORT_SYMBOL_GPL(snd_seq_driver_unregister); /* * module part */ -static int __init alsa_seq_device_init(void) +static int __init seq_dev_proc_init(void) { -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_SND_PROC_FS info_entry = snd_info_create_module_entry(THIS_MODULE, "drivers", snd_seq_root); if (info_entry == NULL) @@ -552,24 +287,29 @@ return 0; } +static int __init alsa_seq_device_init(void) +{ + int err; + + err = bus_register(&snd_seq_bus_type); + if (err < 0) + return err; + err = seq_dev_proc_init(); + if (err < 0) + bus_unregister(&snd_seq_bus_type); + return err; +} + static void __exit alsa_seq_device_exit(void) { - remove_drivers(); -#ifdef CONFIG_PROC_FS +#ifdef CONFIG_MODULES + cancel_work_sync(&autoload_work); +#endif +#ifdef CONFIG_SND_PROC_FS snd_info_free_entry(info_entry); #endif - if (num_ops) - snd_printk(KERN_ERR "drivers not released (%d)\n", num_ops); + bus_unregister(&snd_seq_bus_type); } -module_init(alsa_seq_device_init) +subsys_initcall(alsa_seq_device_init) module_exit(alsa_seq_device_exit) - -EXPORT_SYMBOL(snd_seq_device_load_drivers); -EXPORT_SYMBOL(snd_seq_device_new); -EXPORT_SYMBOL(snd_seq_device_register_driver); -EXPORT_SYMBOL(snd_seq_device_unregister_driver); -#ifdef CONFIG_MODULES -EXPORT_SYMBOL(snd_seq_autoload_lock); -EXPORT_SYMBOL(snd_seq_autoload_unlock); -#endif