inotify: fix race
[linux-2.6.22.y-op.git] / sound / core / sound_oss.c
blob4566df41912a9f15a900914bb4bbc627619edc20
1 /*
2 * Advanced Linux Sound Architecture
3 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <sound/driver.h>
24 #ifdef CONFIG_SND_OSSEMUL
26 #if !defined(CONFIG_SOUND) && !(defined(MODULE) && defined(CONFIG_SOUND_MODULE))
27 #error "Enable the OSS soundcore multiplexer (CONFIG_SOUND) in the kernel."
28 #endif
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/time.h>
33 #include <sound/core.h>
34 #include <sound/minors.h>
35 #include <sound/info.h>
36 #include <linux/sound.h>
37 #include <linux/mutex.h>
39 #define SNDRV_OSS_MINORS 128
41 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
42 static DEFINE_MUTEX(sound_oss_mutex);
44 void *snd_lookup_oss_minor_data(unsigned int minor, int type)
46 struct snd_minor *mreg;
47 void *private_data;
49 if (minor >= ARRAY_SIZE(snd_oss_minors))
50 return NULL;
51 mutex_lock(&sound_oss_mutex);
52 mreg = snd_oss_minors[minor];
53 if (mreg && mreg->type == type)
54 private_data = mreg->private_data;
55 else
56 private_data = NULL;
57 mutex_unlock(&sound_oss_mutex);
58 return private_data;
61 EXPORT_SYMBOL(snd_lookup_oss_minor_data);
63 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
65 int minor;
67 switch (type) {
68 case SNDRV_OSS_DEVICE_TYPE_MIXER:
69 snd_assert(card != NULL && dev <= 1, return -EINVAL);
70 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));
71 break;
72 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
73 minor = SNDRV_MINOR_OSS_SEQUENCER;
74 break;
75 case SNDRV_OSS_DEVICE_TYPE_MUSIC:
76 minor = SNDRV_MINOR_OSS_MUSIC;
77 break;
78 case SNDRV_OSS_DEVICE_TYPE_PCM:
79 snd_assert(card != NULL && dev <= 1, return -EINVAL);
80 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));
81 break;
82 case SNDRV_OSS_DEVICE_TYPE_MIDI:
83 snd_assert(card != NULL && dev <= 1, return -EINVAL);
84 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI));
85 break;
86 case SNDRV_OSS_DEVICE_TYPE_DMFM:
87 minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM);
88 break;
89 case SNDRV_OSS_DEVICE_TYPE_SNDSTAT:
90 minor = SNDRV_MINOR_OSS_SNDSTAT;
91 break;
92 default:
93 return -EINVAL;
95 snd_assert(minor >= 0 && minor < SNDRV_OSS_MINORS, return -EINVAL);
96 return minor;
99 int snd_register_oss_device(int type, struct snd_card *card, int dev,
100 const struct file_operations *f_ops, void *private_data,
101 const char *name)
103 int minor = snd_oss_kernel_minor(type, card, dev);
104 int minor_unit;
105 struct snd_minor *preg;
106 int cidx = SNDRV_MINOR_OSS_CARD(minor);
107 int track2 = -1;
108 int register1 = -1, register2 = -1;
109 struct device *carddev = snd_card_get_device_link(card);
111 if (card && card->number >= 8)
112 return 0; /* ignore silently */
113 if (minor < 0)
114 return minor;
115 preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL);
116 if (preg == NULL)
117 return -ENOMEM;
118 preg->type = type;
119 preg->card = card ? card->number : -1;
120 preg->device = dev;
121 preg->f_ops = f_ops;
122 preg->private_data = private_data;
123 mutex_lock(&sound_oss_mutex);
124 snd_oss_minors[minor] = preg;
125 minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
126 switch (minor_unit) {
127 case SNDRV_MINOR_OSS_PCM:
128 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
129 break;
130 case SNDRV_MINOR_OSS_MIDI:
131 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
132 break;
133 case SNDRV_MINOR_OSS_MIDI1:
134 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
135 break;
137 register1 = register_sound_special_device(f_ops, minor, carddev);
138 if (register1 != minor)
139 goto __end;
140 if (track2 >= 0) {
141 register2 = register_sound_special_device(f_ops, track2,
142 carddev);
143 if (register2 != track2)
144 goto __end;
145 snd_oss_minors[track2] = preg;
147 mutex_unlock(&sound_oss_mutex);
148 return 0;
150 __end:
151 if (register2 >= 0)
152 unregister_sound_special(register2);
153 if (register1 >= 0)
154 unregister_sound_special(register1);
155 snd_oss_minors[minor] = NULL;
156 mutex_unlock(&sound_oss_mutex);
157 kfree(preg);
158 return -EBUSY;
161 EXPORT_SYMBOL(snd_register_oss_device);
163 int snd_unregister_oss_device(int type, struct snd_card *card, int dev)
165 int minor = snd_oss_kernel_minor(type, card, dev);
166 int cidx = SNDRV_MINOR_OSS_CARD(minor);
167 int track2 = -1;
168 struct snd_minor *mptr;
170 if (card && card->number >= 8)
171 return 0;
172 if (minor < 0)
173 return minor;
174 mutex_lock(&sound_oss_mutex);
175 mptr = snd_oss_minors[minor];
176 if (mptr == NULL) {
177 mutex_unlock(&sound_oss_mutex);
178 return -ENOENT;
180 unregister_sound_special(minor);
181 switch (SNDRV_MINOR_OSS_DEVICE(minor)) {
182 case SNDRV_MINOR_OSS_PCM:
183 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
184 break;
185 case SNDRV_MINOR_OSS_MIDI:
186 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
187 break;
188 case SNDRV_MINOR_OSS_MIDI1:
189 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
190 break;
192 if (track2 >= 0) {
193 unregister_sound_special(track2);
194 snd_oss_minors[track2] = NULL;
196 snd_oss_minors[minor] = NULL;
197 mutex_unlock(&sound_oss_mutex);
198 kfree(mptr);
199 return 0;
202 EXPORT_SYMBOL(snd_unregister_oss_device);
205 * INFO PART
208 #ifdef CONFIG_PROC_FS
210 static struct snd_info_entry *snd_minor_info_oss_entry;
212 static const char *snd_oss_device_type_name(int type)
214 switch (type) {
215 case SNDRV_OSS_DEVICE_TYPE_MIXER:
216 return "mixer";
217 case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
218 case SNDRV_OSS_DEVICE_TYPE_MUSIC:
219 return "sequencer";
220 case SNDRV_OSS_DEVICE_TYPE_PCM:
221 return "digital audio";
222 case SNDRV_OSS_DEVICE_TYPE_MIDI:
223 return "raw midi";
224 case SNDRV_OSS_DEVICE_TYPE_DMFM:
225 return "hardware dependent";
226 default:
227 return "?";
231 static void snd_minor_info_oss_read(struct snd_info_entry *entry,
232 struct snd_info_buffer *buffer)
234 int minor;
235 struct snd_minor *mptr;
237 mutex_lock(&sound_oss_mutex);
238 for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {
239 if (!(mptr = snd_oss_minors[minor]))
240 continue;
241 if (mptr->card >= 0)
242 snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,
243 mptr->card, mptr->device,
244 snd_oss_device_type_name(mptr->type));
245 else
246 snd_iprintf(buffer, "%3i: : %s\n", minor,
247 snd_oss_device_type_name(mptr->type));
249 mutex_unlock(&sound_oss_mutex);
253 int __init snd_minor_info_oss_init(void)
255 struct snd_info_entry *entry;
257 entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
258 if (entry) {
259 entry->c.text.read = snd_minor_info_oss_read;
260 if (snd_info_register(entry) < 0) {
261 snd_info_free_entry(entry);
262 entry = NULL;
265 snd_minor_info_oss_entry = entry;
266 return 0;
269 int __exit snd_minor_info_oss_done(void)
271 snd_info_free_entry(snd_minor_info_oss_entry);
272 return 0;
274 #endif /* CONFIG_PROC_FS */
276 #endif /* CONFIG_SND_OSSEMUL */