seq_oss.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * OSS compatible sequencer driver
  4 *
  5 * registration of device and proc
  6 *
  7 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>
  8 */
  9
 10#include <linux/init.h>
 11#include <linux/module.h>
 12#include <linux/mutex.h>
 13#include <linux/compat.h>
 14#include <sound/core.h>
 15#include <sound/minors.h>
 16#include <sound/initval.h>
 17#include "seq_oss_device.h"
 18#include "seq_oss_synth.h"
 19
 20/*
 21 * module option
 22 */
 23MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
 24MODULE_DESCRIPTION("OSS-compatible sequencer module");
 25MODULE_LICENSE("GPL");
 26/* Takashi says this is really only for sound-service-0-, but this is OK. */
 27MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_SEQUENCER);
 28MODULE_ALIAS_SNDRV_MINOR(SNDRV_MINOR_OSS_MUSIC);
 29
 30
 31/*
 32 * prototypes
 33 */
 34static int register_device(void);
 35static void unregister_device(void);
 36#ifdef CONFIG_SND_PROC_FS
 37static int register_proc(void);
 38static void unregister_proc(void);
 39#else
 40static inline int register_proc(void) { return 0; }
 41static inline void unregister_proc(void) {}
 42#endif
 43
 44static int odev_open(struct inode *inode, struct file *file);
 45static int odev_release(struct inode *inode, struct file *file);
 46static ssize_t odev_read(struct file *file, char __user *buf, size_t count, loff_t *offset);
 47static ssize_t odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offset);
 48static long odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 49static __poll_t odev_poll(struct file *file, poll_table * wait);
 50
 51
 52/*
 53 * module interface
 54 */
 55
 56static struct snd_seq_driver seq_oss_synth_driver = {
 57	.driver = {
 58		.name = KBUILD_MODNAME,
 59		.probe = snd_seq_oss_synth_probe,
 60		.remove = snd_seq_oss_synth_remove,
 61	},
 62	.id = SNDRV_SEQ_DEV_ID_OSS,
 63	.argsize = sizeof(struct snd_seq_oss_reg),
 64};
 65
 66static int __init alsa_seq_oss_init(void)
 67{
 68	int rc;
 69
 70	rc = register_device();
 71	if (rc < 0)
 72		goto error;
 73	rc = register_proc();
 74	if (rc < 0) {
 75		unregister_device();
 76		goto error;
 77	}
 78	rc = snd_seq_oss_create_client();
 79	if (rc < 0) {
 80		unregister_proc();
 81		unregister_device();
 82		goto error;
 83	}
 84
 85	rc = snd_seq_driver_register(&seq_oss_synth_driver);
 86	if (rc < 0) {
 87		snd_seq_oss_delete_client();
 88		unregister_proc();
 89		unregister_device();
 90		goto error;
 91	}
 92
 93	/* success */
 94	snd_seq_oss_synth_init();
 95
 96 error:
 97	return rc;
 98}
 99
100static void __exit alsa_seq_oss_exit(void)
101{
102	snd_seq_driver_unregister(&seq_oss_synth_driver);
103	snd_seq_oss_delete_client();
104	unregister_proc();
105	unregister_device();
106}
107
108module_init(alsa_seq_oss_init)
109module_exit(alsa_seq_oss_exit)
110
111/*
112 * ALSA minor device interface
113 */
114
115static DEFINE_MUTEX(register_mutex);
116
117static int
118odev_open(struct inode *inode, struct file *file)
119{
120	int level;
121
122	if (iminor(inode) == SNDRV_MINOR_OSS_MUSIC)
123		level = SNDRV_SEQ_OSS_MODE_MUSIC;
124	else
125		level = SNDRV_SEQ_OSS_MODE_SYNTH;
126
127	guard(mutex)(&register_mutex);
128	return snd_seq_oss_open(file, level);
129}
130
131static int
132odev_release(struct inode *inode, struct file *file)
133{
134	struct seq_oss_devinfo *dp;
135
136	dp = file->private_data;
137	if (!dp)
138		return 0;
139
140	guard(mutex)(&register_mutex);
141	snd_seq_oss_release(dp);
142	return 0;
143}
144
145static ssize_t
146odev_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
147{
148	struct seq_oss_devinfo *dp;
149	dp = file->private_data;
150	if (snd_BUG_ON(!dp))
151		return -ENXIO;
152	return snd_seq_oss_read(dp, buf, count);
153}
154
155
156static ssize_t
157odev_write(struct file *file, const char __user *buf, size_t count, loff_t *offset)
158{
159	struct seq_oss_devinfo *dp;
160	dp = file->private_data;
161	if (snd_BUG_ON(!dp))
162		return -ENXIO;
163	return snd_seq_oss_write(dp, buf, count, file);
164}
165
166static long
167odev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
168{
169	struct seq_oss_devinfo *dp;
170	long rc;
171
172	dp = file->private_data;
173	if (snd_BUG_ON(!dp))
174		return -ENXIO;
175
176	if (cmd != SNDCTL_SEQ_SYNC &&
177	    mutex_lock_interruptible(&register_mutex))
178		return -ERESTARTSYS;
179	rc = snd_seq_oss_ioctl(dp, cmd, arg);
180	if (cmd != SNDCTL_SEQ_SYNC)
181		mutex_unlock(&register_mutex);
182	return rc;
183}
184
185#ifdef CONFIG_COMPAT
186static long odev_ioctl_compat(struct file *file, unsigned int cmd,
187			      unsigned long arg)
188{
189	return odev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
190}
191#else
192#define odev_ioctl_compat	NULL
193#endif
194
195static __poll_t
196odev_poll(struct file *file, poll_table * wait)
197{
198	struct seq_oss_devinfo *dp;
199	dp = file->private_data;
200	if (snd_BUG_ON(!dp))
201		return EPOLLERR;
202	return snd_seq_oss_poll(dp, file, wait);
203}
204
205/*
206 * registration of sequencer minor device
207 */
208
209static const struct file_operations seq_oss_f_ops =
210{
211	.owner =	THIS_MODULE,
212	.read =		odev_read,
213	.write =	odev_write,
214	.open =		odev_open,
215	.release =	odev_release,
216	.poll =		odev_poll,
217	.unlocked_ioctl =	odev_ioctl,
218	.compat_ioctl =	odev_ioctl_compat,
219	.llseek =	noop_llseek,
220};
221
222static int __init
223register_device(void)
224{
225	int rc;
226
227	guard(mutex)(&register_mutex);
228	rc = snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER,
229				     NULL, 0,
230				     &seq_oss_f_ops, NULL);
231	if (rc < 0) {
232		pr_err("ALSA: seq_oss: can't register device seq\n");
233		return rc;
234	}
235	rc = snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MUSIC,
236				     NULL, 0,
237				     &seq_oss_f_ops, NULL);
238	if (rc < 0) {
239		pr_err("ALSA: seq_oss: can't register device music\n");
240		snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER, NULL, 0);
241		return rc;
242	}
243	return 0;
244}
245
246static void
247unregister_device(void)
248{
249	guard(mutex)(&register_mutex);
250	if (snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MUSIC, NULL, 0) < 0)		
251		pr_err("ALSA: seq_oss: error unregister device music\n");
252	if (snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_SEQUENCER, NULL, 0) < 0)
253		pr_err("ALSA: seq_oss: error unregister device seq\n");
254}
255
256/*
257 * /proc interface
258 */
259
260#ifdef CONFIG_SND_PROC_FS
261
262static struct snd_info_entry *info_entry;
263
264static void
265info_read(struct snd_info_entry *entry, struct snd_info_buffer *buf)
266{
267	guard(mutex)(&register_mutex);
268	snd_iprintf(buf, "OSS sequencer emulation version %s\n", SNDRV_SEQ_OSS_VERSION_STR);
269	snd_seq_oss_system_info_read(buf);
270	snd_seq_oss_synth_info_read(buf);
271	snd_seq_oss_midi_info_read(buf);
272}
273
274
275static int __init
276register_proc(void)
277{
278	struct snd_info_entry *entry;
279
280	entry = snd_info_create_module_entry(THIS_MODULE, SNDRV_SEQ_OSS_PROCNAME, snd_seq_root);
281	if (entry == NULL)
282		return -ENOMEM;
283
284	entry->content = SNDRV_INFO_CONTENT_TEXT;
285	entry->private_data = NULL;
286	entry->c.text.read = info_read;
287	if (snd_info_register(entry) < 0) {
288		snd_info_free_entry(entry);
289		return -ENOMEM;
290	}
291	info_entry = entry;
292	return 0;
293}
294
295static void
296unregister_proc(void)
297{
298	snd_info_free_entry(info_entry);
299	info_entry = NULL;
300}
301#endif /* CONFIG_SND_PROC_FS */