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Release 4.17 sound/core/seq_device.c

Directory: sound/core
/*
 *  ALSA sequencer device management
 *  Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
 *
 *   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
 *
 *
 *----------------------------------------------------------------
 *
 * 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, 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; }

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Takashi Iwai4475.86%250.00%
Jaroslav Kysela1424.14%250.00%
Total58100.00%4100.00%

static struct bus_type snd_seq_bus_type = { .name = "snd_seq", .match = snd_seq_bus_match, }; /* * proc interface -- just for compatibility */ #ifdef CONFIG_SND_PROC_FS static 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; }

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Takashi Iwai3353.23%266.67%
Jaroslav Kysela2946.77%133.33%
Total62100.00%3100.00%


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); }

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Takashi Iwai2382.14%150.00%
Jaroslav Kysela517.86%150.00%
Total28100.00%2100.00%

#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; }

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Takashi Iwai2454.55%250.00%
Jaroslav Kysela1943.18%125.00%
Linus Torvalds12.27%125.00%
Total44100.00%4100.00%


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); }

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Takashi Iwai40100.00%2100.00%
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static DECLARE_WORK(autoload_work, autoload_drivers);
static void queue_autoload_drivers(void) { schedule_work(&autoload_work); }

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Takashi Iwai14100.00%2100.00%
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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 }

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Takashi Iwai22100.00%1100.00%
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EXPORT_SYMBOL(snd_seq_autoload_init);
void snd_seq_autoload_exit(void) { atomic_inc(&snd_seq_in_init); }

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Takashi Iwai13100.00%1100.00%
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EXPORT_SYMBOL(snd_seq_autoload_exit);
void snd_seq_device_load_drivers(void) { queue_autoload_drivers(); flush_work(&autoload_work); }

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Takashi Iwai1593.75%150.00%
Jaroslav Kysela16.25%150.00%
Total16100.00%2100.00%

EXPORT_SYMBOL(snd_seq_device_load_drivers); #define cancel_autoload_drivers() cancel_work_sync(&autoload_work) #else #define queue_autoload_drivers() /* NOP */ #define cancel_autoload_drivers() /* NOP */ #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(); put_device(&dev->dev); return 0; }

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Takashi Iwai2573.53%375.00%
Jaroslav Kysela926.47%125.00%
Total34100.00%4100.00%


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; }

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Takashi Iwai57100.00%1100.00%
Total57100.00%1100.00%


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; }

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Takashi Iwai31100.00%1100.00%
Total31100.00%1100.00%


static void snd_seq_dev_release(struct device *dev) { struct snd_seq_device *sdev = to_seq_dev(dev); if (sdev->private_free) sdev->private_free(sdev); kfree(sdev); }

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Takashi Iwai39100.00%1100.00%
Total39100.00%1100.00%

/* * 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 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; dev = kzalloc(sizeof(*dev) + argsize, GFP_KERNEL); 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; }

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Jaroslav Kysela13257.64%333.33%
Takashi Iwai9742.36%666.67%
Total229100.00%9100.00%

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)) return -EINVAL; drv->driver.bus = &snd_seq_bus_type; drv->driver.owner = mod; return driver_register(&drv->driver); }

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Takashi Iwai4166.13%360.00%
Jaroslav Kysela2133.87%240.00%
Total62100.00%5100.00%

EXPORT_SYMBOL_GPL(__snd_seq_driver_register);
void snd_seq_driver_unregister(struct snd_seq_driver *drv) { driver_unregister(&drv->driver); }

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Takashi Iwai1161.11%266.67%
Jaroslav Kysela738.89%133.33%
Total18100.00%3100.00%

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; }

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Jaroslav Kysela6891.89%125.00%
Takashi Iwai68.11%375.00%
Total74100.00%4100.00%


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; }

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Takashi Iwai49100.00%1100.00%
Total49100.00%1100.00%


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); }

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Takashi Iwai2055.56%583.33%
Jaroslav Kysela1644.44%116.67%
Total36100.00%6100.00%

subsys_initcall(alsa_seq_device_init) module_exit(alsa_seq_device_exit)

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Takashi Iwai70464.65%1758.62%
Jaroslav Kysela37634.53%724.14%
Ingo Molnar30.28%13.45%
Paul Gortmaker30.28%13.45%
Johannes Berg10.09%13.45%
Jie Yang10.09%13.45%
Linus Torvalds10.09%13.45%
Total1089100.00%29100.00%
Directory: sound/core
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