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seq_oss.c
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1 /*
2  * OSS compatible sequencer driver
3  *
4  * registration of device and proc
5  *
6  * Copyright (C) 1998,99 Takashi Iwai <[email protected]>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  */
22 
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/mutex.h>
26 #include <sound/core.h>
27 #include <sound/minors.h>
28 #include <sound/initval.h>
29 #include "seq_oss_device.h"
30 #include "seq_oss_synth.h"
31 
32 /*
33  * module option
34  */
35 MODULE_AUTHOR("Takashi Iwai <[email protected]>");
36 MODULE_DESCRIPTION("OSS-compatible sequencer module");
37 MODULE_LICENSE("GPL");
38 /* Takashi says this is really only for sound-service-0-, but this is OK. */
39 MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_SEQUENCER);
40 MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_MUSIC);
41 
42 #ifdef SNDRV_SEQ_OSS_DEBUG
43 module_param(seq_oss_debug, int, 0644);
44 MODULE_PARM_DESC(seq_oss_debug, "debug option");
45 int seq_oss_debug = 0;
46 #endif
47 
48 
49 /*
50  * prototypes
51  */
52 static int register_device(void);
53 static void unregister_device(void);
54 #ifdef CONFIG_PROC_FS
55 static int register_proc(void);
56 static void unregister_proc(void);
57 #else
58 static inline int register_proc(void) { return 0; }
59 static inline void unregister_proc(void) {}
60 #endif
61 
62 static int odev_open(struct inode *inode, struct file *file);
63 static int odev_release(struct inode *inode, struct file *file);
64 static ssize_t odev_read(struct file *file, char __user *buf, size_t count, loff_t *offset);
65 static ssize_t odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offset);
66 static long odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
67 static unsigned int odev_poll(struct file *file, poll_table * wait);
68 
69 
70 /*
71  * module interface
72  */
73 
74 static int __init alsa_seq_oss_init(void)
75 {
76  int rc;
77  static struct snd_seq_dev_ops ops = {
80  };
81 
83  if ((rc = register_device()) < 0)
84  goto error;
85  if ((rc = register_proc()) < 0) {
86  unregister_device();
87  goto error;
88  }
89  if ((rc = snd_seq_oss_create_client()) < 0) {
90  unregister_proc();
91  unregister_device();
92  goto error;
93  }
94 
96  sizeof(struct snd_seq_oss_reg))) < 0) {
98  unregister_proc();
99  unregister_device();
100  goto error;
101  }
102 
103  /* success */
105 
106  error:
108  return rc;
109 }
110 
111 static void __exit alsa_seq_oss_exit(void)
112 {
115  unregister_proc();
116  unregister_device();
117 }
118 
119 module_init(alsa_seq_oss_init)
120 module_exit(alsa_seq_oss_exit)
121 
122 /*
123  * ALSA minor device interface
124  */
125 
126 static DEFINE_MUTEX(register_mutex);
127 
128 static int
129 odev_open(struct inode *inode, struct file *file)
130 {
131  int level, rc;
132 
133  if (iminor(inode) == SNDRV_MINOR_OSS_MUSIC)
134  level = SNDRV_SEQ_OSS_MODE_MUSIC;
135  else
136  level = SNDRV_SEQ_OSS_MODE_SYNTH;
137 
138  mutex_lock(&register_mutex);
139  rc = snd_seq_oss_open(file, level);
140  mutex_unlock(&register_mutex);
141 
142  return rc;
143 }
144 
145 static int
146 odev_release(struct inode *inode, struct file *file)
147 {
148  struct seq_oss_devinfo *dp;
149 
150  if ((dp = file->private_data) == NULL)
151  return 0;
152 
154 
155  mutex_lock(&register_mutex);
157  mutex_unlock(&register_mutex);
158 
159  return 0;
160 }
161 
162 static ssize_t
163 odev_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
164 {
165  struct seq_oss_devinfo *dp;
166  dp = file->private_data;
167  if (snd_BUG_ON(!dp))
168  return -ENXIO;
169  return snd_seq_oss_read(dp, buf, count);
170 }
171 
172 
173 static ssize_t
174 odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
175 {
176  struct seq_oss_devinfo *dp;
177  dp = file->private_data;
178  if (snd_BUG_ON(!dp))
179  return -ENXIO;
180  return snd_seq_oss_write(dp, buf, count, file);
181 }
182 
183 static long
184 odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
185 {
186  struct seq_oss_devinfo *dp;
187  dp = file->private_data;
188  if (snd_BUG_ON(!dp))
189  return -ENXIO;
190  return snd_seq_oss_ioctl(dp, cmd, arg);
191 }
192 
193 #ifdef CONFIG_COMPAT
194 #define odev_ioctl_compat odev_ioctl
195 #else
196 #define odev_ioctl_compat NULL
197 #endif
198 
199 static unsigned int
200 odev_poll(struct file *file, poll_table * wait)
201 {
202  struct seq_oss_devinfo *dp;
203  dp = file->private_data;
204  if (snd_BUG_ON(!dp))
205  return -ENXIO;
206  return snd_seq_oss_poll(dp, file, wait);
207 }
208 
209 /*
210  * registration of sequencer minor device
211  */
212 
213 static const struct file_operations seq_oss_f_ops =
214 {
215  .owner = THIS_MODULE,
216  .read = odev_read,
217  .write = odev_write,
218  .open = odev_open,
219  .release = odev_release,
220  .poll = odev_poll,
221  .unlocked_ioctl = odev_ioctl,
222  .compat_ioctl = odev_ioctl_compat,
223  .llseek = noop_llseek,
224 };
225 
226 static int __init
227 register_device(void)
228 {
229  int rc;
230 
231  mutex_lock(&register_mutex);
232  if ((rc = snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER,
233  NULL, 0,
234  &seq_oss_f_ops, NULL,
235  SNDRV_SEQ_OSS_DEVNAME)) < 0) {
236  snd_printk(KERN_ERR "can't register device seq\n");
237  mutex_unlock(&register_mutex);
238  return rc;
239  }
240  if ((rc = snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MUSIC,
241  NULL, 0,
242  &seq_oss_f_ops, NULL,
243  SNDRV_SEQ_OSS_DEVNAME)) < 0) {
244  snd_printk(KERN_ERR "can't register device music\n");
245  snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER, NULL, 0);
246  mutex_unlock(&register_mutex);
247  return rc;
248  }
249  debug_printk(("device registered\n"));
250  mutex_unlock(&register_mutex);
251  return 0;
252 }
253 
254 static void
255 unregister_device(void)
256 {
257  mutex_lock(&register_mutex);
258  debug_printk(("device unregistered\n"));
259  if (snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MUSIC, NULL, 0) < 0)
260  snd_printk(KERN_ERR "error unregister device music\n");
261  if (snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER, NULL, 0) < 0)
262  snd_printk(KERN_ERR "error unregister device seq\n");
263  mutex_unlock(&register_mutex);
264 }
265 
266 /*
267  * /proc interface
268  */
269 
270 #ifdef CONFIG_PROC_FS
271 
272 static struct snd_info_entry *info_entry;
273 
274 static void
275 info_read(struct snd_info_entry *entry, struct snd_info_buffer *buf)
276 {
277  mutex_lock(&register_mutex);
278  snd_iprintf(buf, "OSS sequencer emulation version %s\n", SNDRV_SEQ_OSS_VERSION_STR);
282  mutex_unlock(&register_mutex);
283 }
284 
285 
286 static int __init
287 register_proc(void)
288 {
289  struct snd_info_entry *entry;
290 
291  entry = snd_info_create_module_entry(THIS_MODULE, SNDRV_SEQ_OSS_PROCNAME, snd_seq_root);
292  if (entry == NULL)
293  return -ENOMEM;
294 
296  entry->private_data = NULL;
297  entry->c.text.read = info_read;
298  if (snd_info_register(entry) < 0) {
299  snd_info_free_entry(entry);
300  return -ENOMEM;
301  }
302  info_entry = entry;
303  return 0;
304 }
305 
306 static void
307 unregister_proc(void)
308 {
309  snd_info_free_entry(info_entry);
310  info_entry = NULL;
311 }
312 #endif /* CONFIG_PROC_FS */