[ALSA] dynamic minors (2/6): simplify storage of snd_minor structures
[safe/jmp/linux-2.6] / sound / core / sound_oss.c
1 /*
2  *  Advanced Linux Sound Architecture
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
4  *
5  *
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.
10  *
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.
15  *
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
19  *
20  */
21
22 #include <sound/driver.h>
23
24 #ifdef CONFIG_SND_OSSEMUL
25
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
29
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
38 #define SNDRV_OSS_MINORS 128
39
40 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
41
42 static DECLARE_MUTEX(sound_oss_mutex);
43
44 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
45 {
46         int minor;
47
48         switch (type) {
49         case SNDRV_OSS_DEVICE_TYPE_MIXER:
50                 snd_assert(card != NULL && dev <= 1, return -EINVAL);
51                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));
52                 break;
53         case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
54                 minor = SNDRV_MINOR_OSS_SEQUENCER;
55                 break;
56         case SNDRV_OSS_DEVICE_TYPE_MUSIC:
57                 minor = SNDRV_MINOR_OSS_MUSIC;
58                 break;
59         case SNDRV_OSS_DEVICE_TYPE_PCM:
60                 snd_assert(card != NULL && dev <= 1, return -EINVAL);
61                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));
62                 break;
63         case SNDRV_OSS_DEVICE_TYPE_MIDI:
64                 snd_assert(card != NULL && dev <= 1, return -EINVAL);
65                 minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI));
66                 break;
67         case SNDRV_OSS_DEVICE_TYPE_DMFM:
68                 minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM);
69                 break;
70         case SNDRV_OSS_DEVICE_TYPE_SNDSTAT:
71                 minor = SNDRV_MINOR_OSS_SNDSTAT;
72                 break;
73         default:
74                 return -EINVAL;
75         }
76         snd_assert(minor >= 0 && minor < SNDRV_OSS_MINORS, return -EINVAL);
77         return minor;
78 }
79
80 int snd_register_oss_device(int type, struct snd_card *card, int dev,
81                             struct file_operations *f_ops, const char *name)
82 {
83         int minor = snd_oss_kernel_minor(type, card, dev);
84         int minor_unit;
85         struct snd_minor *preg;
86         int cidx = SNDRV_MINOR_OSS_CARD(minor);
87         int track2 = -1;
88         int register1 = -1, register2 = -1;
89         struct device *carddev = NULL;
90
91         if (minor < 0)
92                 return minor;
93         preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL);
94         if (preg == NULL)
95                 return -ENOMEM;
96         preg->type = type;
97         preg->card = card ? card->number : -1;
98         preg->device = dev;
99         preg->f_ops = f_ops;
100         down(&sound_oss_mutex);
101         snd_oss_minors[minor] = preg;
102         minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
103         switch (minor_unit) {
104         case SNDRV_MINOR_OSS_PCM:
105                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
106                 break;
107         case SNDRV_MINOR_OSS_MIDI:
108                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
109                 break;
110         case SNDRV_MINOR_OSS_MIDI1:
111                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
112                 break;
113         }
114         if (card)
115                 carddev = card->dev;
116         register1 = register_sound_special_device(f_ops, minor, carddev);
117         if (register1 != minor)
118                 goto __end;
119         if (track2 >= 0) {
120                 register2 = register_sound_special_device(f_ops, track2,
121                                                           carddev);
122                 if (register2 != track2)
123                         goto __end;
124         }
125         up(&sound_oss_mutex);
126         return 0;
127
128       __end:
129         if (register2 >= 0)
130                 unregister_sound_special(register2);
131         if (register1 >= 0)
132                 unregister_sound_special(register1);
133         snd_oss_minors[minor] = NULL;
134         up(&sound_oss_mutex);
135         kfree(preg);
136         return -EBUSY;
137 }
138
139 int snd_unregister_oss_device(int type, struct snd_card *card, int dev)
140 {
141         int minor = snd_oss_kernel_minor(type, card, dev);
142         int cidx = SNDRV_MINOR_OSS_CARD(minor);
143         int track2 = -1;
144         struct snd_minor *mptr;
145
146         if (minor < 0)
147                 return minor;
148         down(&sound_oss_mutex);
149         mptr = snd_oss_minors[minor];
150         if (mptr == NULL) {
151                 up(&sound_oss_mutex);
152                 return -ENOENT;
153         }
154         unregister_sound_special(minor);
155         switch (SNDRV_MINOR_OSS_DEVICE(minor)) {
156         case SNDRV_MINOR_OSS_PCM:
157                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
158                 break;
159         case SNDRV_MINOR_OSS_MIDI:
160                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
161                 break;
162         case SNDRV_MINOR_OSS_MIDI1:
163                 track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
164                 break;
165         }
166         if (track2 >= 0)
167                 unregister_sound_special(track2);
168         snd_oss_minors[minor] = NULL;
169         up(&sound_oss_mutex);
170         kfree(mptr);
171         return 0;
172 }
173
174 /*
175  *  INFO PART
176  */
177
178 #ifdef CONFIG_PROC_FS
179
180 static struct snd_info_entry *snd_minor_info_oss_entry = NULL;
181
182 static const char *snd_oss_device_type_name(int type)
183 {
184         switch (type) {
185         case SNDRV_OSS_DEVICE_TYPE_MIXER:
186                 return "mixer";
187         case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
188         case SNDRV_OSS_DEVICE_TYPE_MUSIC:
189                 return "sequencer";
190         case SNDRV_OSS_DEVICE_TYPE_PCM:
191                 return "digital audio";
192         case SNDRV_OSS_DEVICE_TYPE_MIDI:
193                 return "raw midi";
194         case SNDRV_OSS_DEVICE_TYPE_DMFM:
195                 return "hardware dependent";
196         default:
197                 return "?";
198         }
199 }
200
201 static void snd_minor_info_oss_read(struct snd_info_entry *entry,
202                                     struct snd_info_buffer *buffer)
203 {
204         int minor;
205         struct snd_minor *mptr;
206
207         down(&sound_oss_mutex);
208         for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {
209                 if (!(mptr = snd_oss_minors[minor]))
210                         continue;
211                 if (mptr->card >= 0)
212                         snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,
213                                     mptr->card, mptr->device,
214                                     snd_oss_device_type_name(mptr->type));
215                 else
216                         snd_iprintf(buffer, "%3i:       : %s\n", minor,
217                                     snd_oss_device_type_name(mptr->type));
218         }
219         up(&sound_oss_mutex);
220 }
221
222 #endif /* CONFIG_PROC_FS */
223
224 int __init snd_minor_info_oss_init(void)
225 {
226 #ifdef CONFIG_PROC_FS
227         struct snd_info_entry *entry;
228
229         entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
230         if (entry) {
231                 entry->c.text.read_size = PAGE_SIZE;
232                 entry->c.text.read = snd_minor_info_oss_read;
233                 if (snd_info_register(entry) < 0) {
234                         snd_info_free_entry(entry);
235                         entry = NULL;
236                 }
237         }
238         snd_minor_info_oss_entry = entry;
239 #endif
240         return 0;
241 }
242
243 int __exit snd_minor_info_oss_done(void)
244 {
245 #ifdef CONFIG_PROC_FS
246         if (snd_minor_info_oss_entry)
247                 snd_info_unregister(snd_minor_info_oss_entry);
248 #endif
249         return 0;
250 }
251
252 #endif /* CONFIG_SND_OSSEMUL */