xref: /openbmc/linux/sound/core/sound_oss.c (revision 2223cbec)
1 /*
2  *  Advanced Linux Sound Architecture
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.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 #ifdef CONFIG_SND_OSSEMUL
23 
24 #if !defined(CONFIG_SOUND) && !(defined(MODULE) && defined(CONFIG_SOUND_MODULE))
25 #error "Enable the OSS soundcore multiplexer (CONFIG_SOUND) in the kernel."
26 #endif
27 
28 #include <linux/init.h>
29 #include <linux/export.h>
30 #include <linux/slab.h>
31 #include <linux/time.h>
32 #include <sound/core.h>
33 #include <sound/minors.h>
34 #include <sound/info.h>
35 #include <linux/sound.h>
36 #include <linux/mutex.h>
37 
38 #define SNDRV_OSS_MINORS 256
39 
40 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
41 static DEFINE_MUTEX(sound_oss_mutex);
42 
43 /* NOTE: This function increments the refcount of the associated card like
44  * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately
45  */
46 void *snd_lookup_oss_minor_data(unsigned int minor, int type)
47 {
48 	struct snd_minor *mreg;
49 	void *private_data;
50 
51 	if (minor >= ARRAY_SIZE(snd_oss_minors))
52 		return NULL;
53 	mutex_lock(&sound_oss_mutex);
54 	mreg = snd_oss_minors[minor];
55 	if (mreg && mreg->type == type) {
56 		private_data = mreg->private_data;
57 		if (private_data && mreg->card_ptr)
58 			atomic_inc(&mreg->card_ptr->refcount);
59 	} else
60 		private_data = NULL;
61 	mutex_unlock(&sound_oss_mutex);
62 	return private_data;
63 }
64 
65 EXPORT_SYMBOL(snd_lookup_oss_minor_data);
66 
67 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
68 {
69 	int minor;
70 
71 	switch (type) {
72 	case SNDRV_OSS_DEVICE_TYPE_MIXER:
73 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
74 			return -EINVAL;
75 		minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));
76 		break;
77 	case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
78 		minor = SNDRV_MINOR_OSS_SEQUENCER;
79 		break;
80 	case SNDRV_OSS_DEVICE_TYPE_MUSIC:
81 		minor = SNDRV_MINOR_OSS_MUSIC;
82 		break;
83 	case SNDRV_OSS_DEVICE_TYPE_PCM:
84 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
85 			return -EINVAL;
86 		minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));
87 		break;
88 	case SNDRV_OSS_DEVICE_TYPE_MIDI:
89 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
90 			return -EINVAL;
91 		minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIDI1 : SNDRV_MINOR_OSS_MIDI));
92 		break;
93 	case SNDRV_OSS_DEVICE_TYPE_DMFM:
94 		minor = SNDRV_MINOR_OSS(card->number, SNDRV_MINOR_OSS_DMFM);
95 		break;
96 	case SNDRV_OSS_DEVICE_TYPE_SNDSTAT:
97 		minor = SNDRV_MINOR_OSS_SNDSTAT;
98 		break;
99 	default:
100 		return -EINVAL;
101 	}
102 	if (minor < 0 || minor >= SNDRV_OSS_MINORS)
103 		return -EINVAL;
104 	return minor;
105 }
106 
107 int snd_register_oss_device(int type, struct snd_card *card, int dev,
108 			    const struct file_operations *f_ops, void *private_data,
109 			    const char *name)
110 {
111 	int minor = snd_oss_kernel_minor(type, card, dev);
112 	int minor_unit;
113 	struct snd_minor *preg;
114 	int cidx = SNDRV_MINOR_OSS_CARD(minor);
115 	int track2 = -1;
116 	int register1 = -1, register2 = -1;
117 	struct device *carddev = snd_card_get_device_link(card);
118 
119 	if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
120 		return 0; /* ignore silently */
121 	if (minor < 0)
122 		return minor;
123 	preg = kmalloc(sizeof(struct snd_minor), GFP_KERNEL);
124 	if (preg == NULL)
125 		return -ENOMEM;
126 	preg->type = type;
127 	preg->card = card ? card->number : -1;
128 	preg->device = dev;
129 	preg->f_ops = f_ops;
130 	preg->private_data = private_data;
131 	preg->card_ptr = card;
132 	mutex_lock(&sound_oss_mutex);
133 	snd_oss_minors[minor] = preg;
134 	minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
135 	switch (minor_unit) {
136 	case SNDRV_MINOR_OSS_PCM:
137 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
138 		break;
139 	case SNDRV_MINOR_OSS_MIDI:
140 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
141 		break;
142 	case SNDRV_MINOR_OSS_MIDI1:
143 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
144 		break;
145 	}
146 	register1 = register_sound_special_device(f_ops, minor, carddev);
147 	if (register1 != minor)
148 		goto __end;
149 	if (track2 >= 0) {
150 		register2 = register_sound_special_device(f_ops, track2,
151 							  carddev);
152 		if (register2 != track2)
153 			goto __end;
154 		snd_oss_minors[track2] = preg;
155 	}
156 	mutex_unlock(&sound_oss_mutex);
157 	return 0;
158 
159       __end:
160       	if (register2 >= 0)
161       		unregister_sound_special(register2);
162       	if (register1 >= 0)
163       		unregister_sound_special(register1);
164 	snd_oss_minors[minor] = NULL;
165 	mutex_unlock(&sound_oss_mutex);
166 	kfree(preg);
167       	return -EBUSY;
168 }
169 
170 EXPORT_SYMBOL(snd_register_oss_device);
171 
172 int snd_unregister_oss_device(int type, struct snd_card *card, int dev)
173 {
174 	int minor = snd_oss_kernel_minor(type, card, dev);
175 	int cidx = SNDRV_MINOR_OSS_CARD(minor);
176 	int track2 = -1;
177 	struct snd_minor *mptr;
178 
179 	if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
180 		return 0;
181 	if (minor < 0)
182 		return minor;
183 	mutex_lock(&sound_oss_mutex);
184 	mptr = snd_oss_minors[minor];
185 	if (mptr == NULL) {
186 		mutex_unlock(&sound_oss_mutex);
187 		return -ENOENT;
188 	}
189 	unregister_sound_special(minor);
190 	switch (SNDRV_MINOR_OSS_DEVICE(minor)) {
191 	case SNDRV_MINOR_OSS_PCM:
192 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
193 		break;
194 	case SNDRV_MINOR_OSS_MIDI:
195 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
196 		break;
197 	case SNDRV_MINOR_OSS_MIDI1:
198 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
199 		break;
200 	}
201 	if (track2 >= 0) {
202 		unregister_sound_special(track2);
203 		snd_oss_minors[track2] = NULL;
204 	}
205 	snd_oss_minors[minor] = NULL;
206 	mutex_unlock(&sound_oss_mutex);
207 	kfree(mptr);
208 	return 0;
209 }
210 
211 EXPORT_SYMBOL(snd_unregister_oss_device);
212 
213 /*
214  *  INFO PART
215  */
216 
217 #ifdef CONFIG_PROC_FS
218 
219 static struct snd_info_entry *snd_minor_info_oss_entry;
220 
221 static const char *snd_oss_device_type_name(int type)
222 {
223 	switch (type) {
224 	case SNDRV_OSS_DEVICE_TYPE_MIXER:
225 		return "mixer";
226 	case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
227 	case SNDRV_OSS_DEVICE_TYPE_MUSIC:
228 		return "sequencer";
229 	case SNDRV_OSS_DEVICE_TYPE_PCM:
230 		return "digital audio";
231 	case SNDRV_OSS_DEVICE_TYPE_MIDI:
232 		return "raw midi";
233 	case SNDRV_OSS_DEVICE_TYPE_DMFM:
234 		return "hardware dependent";
235 	default:
236 		return "?";
237 	}
238 }
239 
240 static void snd_minor_info_oss_read(struct snd_info_entry *entry,
241 				    struct snd_info_buffer *buffer)
242 {
243 	int minor;
244 	struct snd_minor *mptr;
245 
246 	mutex_lock(&sound_oss_mutex);
247 	for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {
248 		if (!(mptr = snd_oss_minors[minor]))
249 			continue;
250 		if (mptr->card >= 0)
251 			snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,
252 				    mptr->card, mptr->device,
253 				    snd_oss_device_type_name(mptr->type));
254 		else
255 			snd_iprintf(buffer, "%3i:       : %s\n", minor,
256 				    snd_oss_device_type_name(mptr->type));
257 	}
258 	mutex_unlock(&sound_oss_mutex);
259 }
260 
261 
262 int __init snd_minor_info_oss_init(void)
263 {
264 	struct snd_info_entry *entry;
265 
266 	entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
267 	if (entry) {
268 		entry->c.text.read = snd_minor_info_oss_read;
269 		if (snd_info_register(entry) < 0) {
270 			snd_info_free_entry(entry);
271 			entry = NULL;
272 		}
273 	}
274 	snd_minor_info_oss_entry = entry;
275 	return 0;
276 }
277 
278 int __exit snd_minor_info_oss_done(void)
279 {
280 	snd_info_free_entry(snd_minor_info_oss_entry);
281 	return 0;
282 }
283 #endif /* CONFIG_PROC_FS */
284 
285 #endif /* CONFIG_SND_OSSEMUL */
286