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v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Misc and compatibility things
  4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  5 */
  6
  7#include <linux/init.h>
  8#include <linux/export.h>
  9#include <linux/moduleparam.h>
 10#include <linux/time.h>
 11#include <linux/slab.h>
 12#include <linux/ioport.h>
 
 13#include <sound/core.h>
 14
 15#ifdef CONFIG_SND_DEBUG
 16
 17#ifdef CONFIG_SND_DEBUG_VERBOSE
 18#define DEFAULT_DEBUG_LEVEL	2
 19#else
 20#define DEFAULT_DEBUG_LEVEL	1
 21#endif
 22
 23static int debug = DEFAULT_DEBUG_LEVEL;
 24module_param(debug, int, 0644);
 25MODULE_PARM_DESC(debug, "Debug level (0 = disable)");
 26
 27#endif /* CONFIG_SND_DEBUG */
 28
 29void release_and_free_resource(struct resource *res)
 30{
 31	if (res) {
 32		release_resource(res);
 33		kfree(res);
 34	}
 35}
 36EXPORT_SYMBOL(release_and_free_resource);
 37
 38#ifdef CONFIG_SND_VERBOSE_PRINTK
 39/* strip the leading path if the given path is absolute */
 40static const char *sanity_file_name(const char *path)
 41{
 42	if (*path == '/')
 43		return strrchr(path, '/') + 1;
 44	else
 45		return path;
 46}
 47#endif
 48
 49#if defined(CONFIG_SND_DEBUG) || defined(CONFIG_SND_VERBOSE_PRINTK)
 50void __snd_printk(unsigned int level, const char *path, int line,
 51		  const char *format, ...)
 52{
 53	va_list args;
 54#ifdef CONFIG_SND_VERBOSE_PRINTK
 55	int kern_level;
 56	struct va_format vaf;
 57	char verbose_fmt[] = KERN_DEFAULT "ALSA %s:%d %pV";
 58	bool level_found = false;
 59#endif
 60
 61#ifdef CONFIG_SND_DEBUG
 62	if (debug < level)
 63		return;
 64#endif
 65
 66	va_start(args, format);
 67#ifdef CONFIG_SND_VERBOSE_PRINTK
 68	vaf.fmt = format;
 69	vaf.va = &args;
 70
 71	while ((kern_level = printk_get_level(vaf.fmt)) != 0) {
 72		const char *end_of_header = printk_skip_level(vaf.fmt);
 73
 74		/* Ignore KERN_CONT. We print filename:line for each piece. */
 75		if (kern_level >= '0' && kern_level <= '7') {
 76			memcpy(verbose_fmt, vaf.fmt, end_of_header - vaf.fmt);
 77			level_found = true;
 78		}
 79
 80		vaf.fmt = end_of_header;
 81	}
 82
 83	if (!level_found && level)
 84		memcpy(verbose_fmt, KERN_DEBUG, sizeof(KERN_DEBUG) - 1);
 85
 86	printk(verbose_fmt, sanity_file_name(path), line, &vaf);
 87#else
 88	vprintk(format, args);
 89#endif
 90	va_end(args);
 91}
 92EXPORT_SYMBOL_GPL(__snd_printk);
 93#endif
 94
 95#ifdef CONFIG_PCI
 96#include <linux/pci.h>
 97/**
 98 * snd_pci_quirk_lookup_id - look up a PCI SSID quirk list
 99 * @vendor: PCI SSV id
100 * @device: PCI SSD id
101 * @list: quirk list, terminated by a null entry
102 *
103 * Look through the given quirk list and finds a matching entry
104 * with the same PCI SSID.  When subdevice is 0, all subdevice
105 * values may match.
106 *
107 * Returns the matched entry pointer, or NULL if nothing matched.
108 */
109const struct snd_pci_quirk *
110snd_pci_quirk_lookup_id(u16 vendor, u16 device,
111			const struct snd_pci_quirk *list)
112{
113	const struct snd_pci_quirk *q;
114
115	for (q = list; q->subvendor; q++) {
116		if (q->subvendor != vendor)
117			continue;
118		if (!q->subdevice ||
119		    (device & q->subdevice_mask) == q->subdevice)
120			return q;
121	}
122	return NULL;
123}
124EXPORT_SYMBOL(snd_pci_quirk_lookup_id);
125
126/**
127 * snd_pci_quirk_lookup - look up a PCI SSID quirk list
128 * @pci: pci_dev handle
129 * @list: quirk list, terminated by a null entry
130 *
131 * Look through the given quirk list and finds a matching entry
132 * with the same PCI SSID.  When subdevice is 0, all subdevice
133 * values may match.
134 *
135 * Returns the matched entry pointer, or NULL if nothing matched.
136 */
137const struct snd_pci_quirk *
138snd_pci_quirk_lookup(struct pci_dev *pci, const struct snd_pci_quirk *list)
139{
140	if (!pci)
141		return NULL;
142	return snd_pci_quirk_lookup_id(pci->subsystem_vendor,
143				       pci->subsystem_device,
144				       list);
145}
146EXPORT_SYMBOL(snd_pci_quirk_lookup);
147#endif
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Misc and compatibility things
  4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  5 */
  6
  7#include <linux/init.h>
  8#include <linux/export.h>
  9#include <linux/moduleparam.h>
 10#include <linux/time.h>
 11#include <linux/slab.h>
 12#include <linux/ioport.h>
 13#include <linux/fs.h>
 14#include <sound/core.h>
 15
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 16void release_and_free_resource(struct resource *res)
 17{
 18	if (res) {
 19		release_resource(res);
 20		kfree(res);
 21	}
 22}
 23EXPORT_SYMBOL(release_and_free_resource);
 24
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 25#ifdef CONFIG_PCI
 26#include <linux/pci.h>
 27/**
 28 * snd_pci_quirk_lookup_id - look up a PCI SSID quirk list
 29 * @vendor: PCI SSV id
 30 * @device: PCI SSD id
 31 * @list: quirk list, terminated by a null entry
 32 *
 33 * Look through the given quirk list and finds a matching entry
 34 * with the same PCI SSID.  When subdevice is 0, all subdevice
 35 * values may match.
 36 *
 37 * Returns the matched entry pointer, or NULL if nothing matched.
 38 */
 39const struct snd_pci_quirk *
 40snd_pci_quirk_lookup_id(u16 vendor, u16 device,
 41			const struct snd_pci_quirk *list)
 42{
 43	const struct snd_pci_quirk *q;
 44
 45	for (q = list; q->subvendor || q->subdevice; q++) {
 46		if (q->subvendor != vendor)
 47			continue;
 48		if (!q->subdevice ||
 49		    (device & q->subdevice_mask) == q->subdevice)
 50			return q;
 51	}
 52	return NULL;
 53}
 54EXPORT_SYMBOL(snd_pci_quirk_lookup_id);
 55
 56/**
 57 * snd_pci_quirk_lookup - look up a PCI SSID quirk list
 58 * @pci: pci_dev handle
 59 * @list: quirk list, terminated by a null entry
 60 *
 61 * Look through the given quirk list and finds a matching entry
 62 * with the same PCI SSID.  When subdevice is 0, all subdevice
 63 * values may match.
 64 *
 65 * Returns the matched entry pointer, or NULL if nothing matched.
 66 */
 67const struct snd_pci_quirk *
 68snd_pci_quirk_lookup(struct pci_dev *pci, const struct snd_pci_quirk *list)
 69{
 70	if (!pci)
 71		return NULL;
 72	return snd_pci_quirk_lookup_id(pci->subsystem_vendor,
 73				       pci->subsystem_device,
 74				       list);
 75}
 76EXPORT_SYMBOL(snd_pci_quirk_lookup);
 77#endif
 78
 79/*
 80 * Deferred async signal helpers
 81 *
 82 * Below are a few helper functions to wrap the async signal handling
 83 * in the deferred work.  The main purpose is to avoid the messy deadlock
 84 * around tasklist_lock and co at the kill_fasync() invocation.
 85 * fasync_helper() and kill_fasync() are replaced with snd_fasync_helper()
 86 * and snd_kill_fasync(), respectively.  In addition, snd_fasync_free() has
 87 * to be called at releasing the relevant file object.
 88 */
 89struct snd_fasync {
 90	struct fasync_struct *fasync;
 91	int signal;
 92	int poll;
 93	int on;
 94	struct list_head list;
 95};
 96
 97static DEFINE_SPINLOCK(snd_fasync_lock);
 98static LIST_HEAD(snd_fasync_list);
 99
100static void snd_fasync_work_fn(struct work_struct *work)
101{
102	struct snd_fasync *fasync;
103
104	spin_lock_irq(&snd_fasync_lock);
105	while (!list_empty(&snd_fasync_list)) {
106		fasync = list_first_entry(&snd_fasync_list, struct snd_fasync, list);
107		list_del_init(&fasync->list);
108		spin_unlock_irq(&snd_fasync_lock);
109		if (fasync->on)
110			kill_fasync(&fasync->fasync, fasync->signal, fasync->poll);
111		spin_lock_irq(&snd_fasync_lock);
112	}
113	spin_unlock_irq(&snd_fasync_lock);
114}
115
116static DECLARE_WORK(snd_fasync_work, snd_fasync_work_fn);
117
118int snd_fasync_helper(int fd, struct file *file, int on,
119		      struct snd_fasync **fasyncp)
120{
121	struct snd_fasync *fasync = NULL;
122
123	if (on) {
124		fasync = kzalloc(sizeof(*fasync), GFP_KERNEL);
125		if (!fasync)
126			return -ENOMEM;
127		INIT_LIST_HEAD(&fasync->list);
128	}
129
130	spin_lock_irq(&snd_fasync_lock);
131	if (*fasyncp) {
132		kfree(fasync);
133		fasync = *fasyncp;
134	} else {
135		if (!fasync) {
136			spin_unlock_irq(&snd_fasync_lock);
137			return 0;
138		}
139		*fasyncp = fasync;
140	}
141	fasync->on = on;
142	spin_unlock_irq(&snd_fasync_lock);
143	return fasync_helper(fd, file, on, &fasync->fasync);
144}
145EXPORT_SYMBOL_GPL(snd_fasync_helper);
146
147void snd_kill_fasync(struct snd_fasync *fasync, int signal, int poll)
148{
149	unsigned long flags;
150
151	if (!fasync || !fasync->on)
152		return;
153	spin_lock_irqsave(&snd_fasync_lock, flags);
154	fasync->signal = signal;
155	fasync->poll = poll;
156	list_move(&fasync->list, &snd_fasync_list);
157	schedule_work(&snd_fasync_work);
158	spin_unlock_irqrestore(&snd_fasync_lock, flags);
159}
160EXPORT_SYMBOL_GPL(snd_kill_fasync);
161
162void snd_fasync_free(struct snd_fasync *fasync)
163{
164	if (!fasync)
165		return;
166	fasync->on = 0;
167	flush_work(&snd_fasync_work);
168	kfree(fasync);
169}
170EXPORT_SYMBOL_GPL(snd_fasync_free);