linux/sound/core/misc.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Misc and compatibility things
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 */

#include <linux/init.h>
#include <linux/export.h>
#include <linux/moduleparam.h>
#include <linux/time.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/fs.h>
#include <sound/core.h>

void release_and_free_resource(struct resource *res)
{ … }
EXPORT_SYMBOL(…);

#ifdef CONFIG_PCI
#include <linux/pci.h>
/**
 * snd_pci_quirk_lookup_id - look up a PCI SSID quirk list
 * @vendor: PCI SSV id
 * @device: PCI SSD id
 * @list: quirk list, terminated by a null entry
 *
 * Look through the given quirk list and finds a matching entry
 * with the same PCI SSID.  When subdevice is 0, all subdevice
 * values may match.
 *
 * Returns the matched entry pointer, or NULL if nothing matched.
 */
const struct snd_pci_quirk *
snd_pci_quirk_lookup_id(u16 vendor, u16 device,
			const struct snd_pci_quirk *list)
{ … }
EXPORT_SYMBOL(…);

/**
 * snd_pci_quirk_lookup - look up a PCI SSID quirk list
 * @pci: pci_dev handle
 * @list: quirk list, terminated by a null entry
 *
 * Look through the given quirk list and finds a matching entry
 * with the same PCI SSID.  When subdevice is 0, all subdevice
 * values may match.
 *
 * Returns the matched entry pointer, or NULL if nothing matched.
 */
const struct snd_pci_quirk *
snd_pci_quirk_lookup(struct pci_dev *pci, const struct snd_pci_quirk *list)
{ … }
EXPORT_SYMBOL(…);
#endif

/*
 * Deferred async signal helpers
 *
 * Below are a few helper functions to wrap the async signal handling
 * in the deferred work.  The main purpose is to avoid the messy deadlock
 * around tasklist_lock and co at the kill_fasync() invocation.
 * fasync_helper() and kill_fasync() are replaced with snd_fasync_helper()
 * and snd_kill_fasync(), respectively.  In addition, snd_fasync_free() has
 * to be called at releasing the relevant file object.
 */
struct snd_fasync { … };

static DEFINE_SPINLOCK(snd_fasync_lock);
static LIST_HEAD(snd_fasync_list);

static void snd_fasync_work_fn(struct work_struct *work)
{ … }

static DECLARE_WORK(snd_fasync_work, snd_fasync_work_fn);

int snd_fasync_helper(int fd, struct file *file, int on,
		      struct snd_fasync **fasyncp)
{ … }
EXPORT_SYMBOL_GPL(…);

void snd_kill_fasync(struct snd_fasync *fasync, int signal, int poll)
{ … }
EXPORT_SYMBOL_GPL(…);

void snd_fasync_free(struct snd_fasync *fasync)
{ … }
EXPORT_SYMBOL_GPL(…);