xref: /openbmc/linux/sound/core/sound_oss.c (revision ebd09753)
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 #include <linux/init.h>
23 #include <linux/export.h>
24 #include <linux/slab.h>
25 #include <linux/time.h>
26 #include <sound/core.h>
27 #include <sound/minors.h>
28 #include <sound/info.h>
29 #include <linux/sound.h>
30 #include <linux/mutex.h>
31 
32 #define SNDRV_OSS_MINORS 256
33 
34 static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
35 static DEFINE_MUTEX(sound_oss_mutex);
36 
37 /* NOTE: This function increments the refcount of the associated card like
38  * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately
39  */
40 void *snd_lookup_oss_minor_data(unsigned int minor, int type)
41 {
42 	struct snd_minor *mreg;
43 	void *private_data;
44 
45 	if (minor >= ARRAY_SIZE(snd_oss_minors))
46 		return NULL;
47 	mutex_lock(&sound_oss_mutex);
48 	mreg = snd_oss_minors[minor];
49 	if (mreg && mreg->type == type) {
50 		private_data = mreg->private_data;
51 		if (private_data && mreg->card_ptr)
52 			get_device(&mreg->card_ptr->card_dev);
53 	} else
54 		private_data = NULL;
55 	mutex_unlock(&sound_oss_mutex);
56 	return private_data;
57 }
58 EXPORT_SYMBOL(snd_lookup_oss_minor_data);
59 
60 static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
61 {
62 	int minor;
63 
64 	switch (type) {
65 	case SNDRV_OSS_DEVICE_TYPE_MIXER:
66 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
67 			return -EINVAL;
68 		minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_MIXER1 : SNDRV_MINOR_OSS_MIXER));
69 		break;
70 	case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
71 		minor = SNDRV_MINOR_OSS_SEQUENCER;
72 		break;
73 	case SNDRV_OSS_DEVICE_TYPE_MUSIC:
74 		minor = SNDRV_MINOR_OSS_MUSIC;
75 		break;
76 	case SNDRV_OSS_DEVICE_TYPE_PCM:
77 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
78 			return -EINVAL;
79 		minor = SNDRV_MINOR_OSS(card->number, (dev ? SNDRV_MINOR_OSS_PCM1 : SNDRV_MINOR_OSS_PCM));
80 		break;
81 	case SNDRV_OSS_DEVICE_TYPE_MIDI:
82 		if (snd_BUG_ON(!card || dev < 0 || dev > 1))
83 			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;
94 	}
95 	if (minor < 0 || minor >= SNDRV_OSS_MINORS)
96 		return -EINVAL;
97 	return minor;
98 }
99 
100 int snd_register_oss_device(int type, struct snd_card *card, int dev,
101 			    const struct file_operations *f_ops, void *private_data)
102 {
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);
110 
111 	if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
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 	preg->card_ptr = card;
124 	mutex_lock(&sound_oss_mutex);
125 	snd_oss_minors[minor] = preg;
126 	minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
127 	switch (minor_unit) {
128 	case SNDRV_MINOR_OSS_PCM:
129 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_AUDIO);
130 		break;
131 	case SNDRV_MINOR_OSS_MIDI:
132 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI);
133 		break;
134 	case SNDRV_MINOR_OSS_MIDI1:
135 		track2 = SNDRV_MINOR_OSS(cidx, SNDRV_MINOR_OSS_DMMIDI1);
136 		break;
137 	}
138 	register1 = register_sound_special_device(f_ops, minor, carddev);
139 	if (register1 != minor)
140 		goto __end;
141 	if (track2 >= 0) {
142 		register2 = register_sound_special_device(f_ops, track2,
143 							  carddev);
144 		if (register2 != track2)
145 			goto __end;
146 		snd_oss_minors[track2] = preg;
147 	}
148 	mutex_unlock(&sound_oss_mutex);
149 	return 0;
150 
151       __end:
152       	if (register2 >= 0)
153       		unregister_sound_special(register2);
154       	if (register1 >= 0)
155       		unregister_sound_special(register1);
156 	snd_oss_minors[minor] = NULL;
157 	mutex_unlock(&sound_oss_mutex);
158 	kfree(preg);
159       	return -EBUSY;
160 }
161 EXPORT_SYMBOL(snd_register_oss_device);
162 
163 int snd_unregister_oss_device(int type, struct snd_card *card, int dev)
164 {
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;
169 
170 	if (card && card->number >= SNDRV_MINOR_OSS_DEVICES)
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;
179 	}
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;
191 	}
192 	if (track2 >= 0) {
193 		unregister_sound_special(track2);
194 		snd_oss_minors[track2] = NULL;
195 	}
196 	snd_oss_minors[minor] = NULL;
197 	mutex_unlock(&sound_oss_mutex);
198 	kfree(mptr);
199 	return 0;
200 }
201 EXPORT_SYMBOL(snd_unregister_oss_device);
202 
203 /*
204  *  INFO PART
205  */
206 
207 #ifdef CONFIG_SND_PROC_FS
208 static const char *snd_oss_device_type_name(int type)
209 {
210 	switch (type) {
211 	case SNDRV_OSS_DEVICE_TYPE_MIXER:
212 		return "mixer";
213 	case SNDRV_OSS_DEVICE_TYPE_SEQUENCER:
214 	case SNDRV_OSS_DEVICE_TYPE_MUSIC:
215 		return "sequencer";
216 	case SNDRV_OSS_DEVICE_TYPE_PCM:
217 		return "digital audio";
218 	case SNDRV_OSS_DEVICE_TYPE_MIDI:
219 		return "raw midi";
220 	case SNDRV_OSS_DEVICE_TYPE_DMFM:
221 		return "hardware dependent";
222 	default:
223 		return "?";
224 	}
225 }
226 
227 static void snd_minor_info_oss_read(struct snd_info_entry *entry,
228 				    struct snd_info_buffer *buffer)
229 {
230 	int minor;
231 	struct snd_minor *mptr;
232 
233 	mutex_lock(&sound_oss_mutex);
234 	for (minor = 0; minor < SNDRV_OSS_MINORS; ++minor) {
235 		if (!(mptr = snd_oss_minors[minor]))
236 			continue;
237 		if (mptr->card >= 0)
238 			snd_iprintf(buffer, "%3i: [%i-%2i]: %s\n", minor,
239 				    mptr->card, mptr->device,
240 				    snd_oss_device_type_name(mptr->type));
241 		else
242 			snd_iprintf(buffer, "%3i:       : %s\n", minor,
243 				    snd_oss_device_type_name(mptr->type));
244 	}
245 	mutex_unlock(&sound_oss_mutex);
246 }
247 
248 
249 int __init snd_minor_info_oss_init(void)
250 {
251 	struct snd_info_entry *entry;
252 
253 	entry = snd_info_create_module_entry(THIS_MODULE, "devices", snd_oss_root);
254 	if (!entry)
255 		return -ENOMEM;
256 	entry->c.text.read = snd_minor_info_oss_read;
257 	return snd_info_register(entry); /* freed in error path */
258 }
259 #endif /* CONFIG_SND_PROC_FS */
260