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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338// SPDX-License-Identifier: GPL-2.0-or-later/* * ALSA sequencer device management * Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de> * *---------------------------------------------------------------- * * This device handler separates the card driver module from sequencer * stuff (sequencer core, synth drivers, etc), so that user can avoid * to spend unnecessary resources e.g. if he needs only listening to * MP3s. * * The card (or lowlevel) driver creates a sequencer device entry * via snd_seq_device_new(). This is an entry pointer to communicate * with the sequencer device "driver", which is involved with the * actual part to communicate with the sequencer core. * Each sequencer device entry has an id string and the corresponding * driver with the same id is loaded when required. For example, * lowlevel codes to access emu8000 chip on sbawe card are included in * emu8000-synth module. To activate this module, the hardware * resources like i/o port are passed via snd_seq_device argument. */
#include <linux/device.h>#include <linux/init.h>#include <linux/module.h>#include <sound/core.h>#include <sound/info.h>#include <sound/seq_device.h>#include <sound/seq_kernel.h>#include <sound/initval.h>#include <linux/kmod.h>#include <linux/slab.h>#include <linux/mutex.h>
MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");MODULE_DESCRIPTION("ALSA sequencer device management");MODULE_LICENSE("GPL");
/* * bus definition */static int snd_seq_bus_match(struct device *dev, const struct device_driver *drv){ struct snd_seq_device *sdev = to_seq_dev(dev); const struct snd_seq_driver *sdrv = to_seq_drv(drv);
return strcmp(sdrv->id, sdev->id) == 0 && sdrv->argsize == sdev->argsize;}
static int snd_seq_bus_probe(struct device *dev){ struct snd_seq_device *sdev = to_seq_dev(dev); const struct snd_seq_driver *sdrv = to_seq_drv(dev->driver);
if (sdrv->probe) return sdrv->probe(sdev); else return 0;}
static void snd_seq_bus_remove(struct device *dev){ struct snd_seq_device *sdev = to_seq_dev(dev); const struct snd_seq_driver *sdrv = to_seq_drv(dev->driver);
if (sdrv->remove) sdrv->remove(sdev);}
static const struct bus_type snd_seq_bus_type = { .name = "snd_seq", .match = snd_seq_bus_match, .probe = snd_seq_bus_probe, .remove = snd_seq_bus_remove,};
/* * proc interface -- just for compatibility */#ifdef CONFIG_SND_PROC_FSstatic struct snd_info_entry *info_entry;
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;}
static void snd_seq_device_info(struct snd_info_entry *entry, struct snd_info_buffer *buffer){ 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/* 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){ struct snd_seq_device *sdev = to_seq_dev(dev);
if (!dev->driver) request_module("snd-%s", sdev->id); return 0;}
static void autoload_drivers(struct work_struct *work){ /* 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);}
static DECLARE_WORK(autoload_work, autoload_drivers);
static void queue_autoload_drivers(void){ schedule_work(&autoload_work);}
void snd_seq_autoload_init(void){ 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);
void snd_seq_autoload_exit(void){ atomic_inc(&snd_seq_in_init);}EXPORT_SYMBOL(snd_seq_autoload_exit);
void snd_seq_device_load_drivers(void){ queue_autoload_drivers(); flush_work(&autoload_work);}EXPORT_SYMBOL(snd_seq_device_load_drivers);
static inline void cancel_autoload_drivers(void){ cancel_work_sync(&autoload_work);}#elsestatic inline void queue_autoload_drivers(void){}
static inline void cancel_autoload_drivers(void){}#endif
/* * device management */static int snd_seq_device_dev_free(struct snd_device *device){ struct snd_seq_device *dev = device->device_data;
cancel_autoload_drivers(); if (dev->private_free) dev->private_free(dev); put_device(&dev->dev); return 0;}
static int snd_seq_device_dev_register(struct snd_device *device){ struct snd_seq_device *dev = device->device_data; int err;
err = device_add(&dev->dev); if (err < 0) return err; if (!dev->dev.driver) queue_autoload_drivers(); return 0;}
static int snd_seq_device_dev_disconnect(struct snd_device *device){ struct snd_seq_device *dev = device->device_data;
device_del(&dev->dev); return 0;}
static void snd_seq_dev_release(struct device *dev){ kfree(to_seq_dev(dev));}
/* * 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_new(struct snd_card *card, int device, const char *id, int argsize, struct snd_seq_device **result){ struct snd_seq_device *dev; int err; static const 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;
if (argsize < 0) return -EINVAL;
dev = kzalloc_flex(*dev, args, argsize); if (!dev) return -ENOMEM;
/* set up device info */ dev->card = card; dev->device = device; dev->id = id; dev->argsize = argsize;
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);
/* 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);
/* * driver registration */int __snd_seq_driver_register(struct snd_seq_driver *drv, struct module *mod){ if (WARN_ON(!drv->driver.name || !drv->id || drv->driver.probe || drv->driver.remove)) return -EINVAL;
drv->driver.bus = &snd_seq_bus_type; drv->driver.owner = mod;
return driver_register(&drv->driver);}EXPORT_SYMBOL_GPL(__snd_seq_driver_register);
void snd_seq_driver_unregister(struct snd_seq_driver *drv){ driver_unregister(&drv->driver);}EXPORT_SYMBOL_GPL(snd_seq_driver_unregister);
/* * module part */
static int __init seq_dev_proc_init(void){#ifdef CONFIG_SND_PROC_FS info_entry = snd_info_create_module_entry(THIS_MODULE, "drivers", snd_seq_root); if (info_entry == NULL) return -ENOMEM; info_entry->content = SNDRV_INFO_CONTENT_TEXT; info_entry->c.text.read = snd_seq_device_info; if (snd_info_register(info_entry) < 0) { snd_info_free_entry(info_entry); return -ENOMEM; }#endif 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){#ifdef CONFIG_MODULES cancel_work_sync(&autoload_work);#endif#ifdef CONFIG_SND_PROC_FS snd_info_free_entry(info_entry);#endif bus_unregister(&snd_seq_bus_type);}
subsys_initcall(alsa_seq_device_init)module_exit(alsa_seq_device_exit)