tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2002 Steve Schmidtke
4 */
5
6#include <linux/fs.h>
7#include <linux/module.h>
8#include <linux/slab.h>
9#include <linux/sound.h>
10#include <linux/soundcard.h>
11#include <linux/mutex.h>
12#include <linux/uaccess.h>
13#include <init.h>
14#include <os.h>
15
16struct hostaudio_state {
17 int fd;
18};
19
20struct hostmixer_state {
21 int fd;
22};
23
24#define HOSTAUDIO_DEV_DSP "/dev/sound/dsp"
25#define HOSTAUDIO_DEV_MIXER "/dev/sound/mixer"
26
27/*
28 * Changed either at boot time or module load time. At boot, this is
29 * single-threaded; at module load, multiple modules would each have
30 * their own copy of these variables.
31 */
32static char *dsp = HOSTAUDIO_DEV_DSP;
33static char *mixer = HOSTAUDIO_DEV_MIXER;
34
35#define DSP_HELP \
36" This is used to specify the host dsp device to the hostaudio driver.\n" \
37" The default is \"" HOSTAUDIO_DEV_DSP "\".\n\n"
38
39#define MIXER_HELP \
40" This is used to specify the host mixer device to the hostaudio driver.\n"\
41" The default is \"" HOSTAUDIO_DEV_MIXER "\".\n\n"
42
43module_param(dsp, charp, 0644);
44MODULE_PARM_DESC(dsp, DSP_HELP);
45module_param(mixer, charp, 0644);
46MODULE_PARM_DESC(mixer, MIXER_HELP);
47
48#ifndef MODULE
49static int set_dsp(char *name, int *add)
50{
51 dsp = name;
52 return 0;
53}
54
55__uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
56
57static int set_mixer(char *name, int *add)
58{
59 mixer = name;
60 return 0;
61}
62
63__uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
64#endif
65
66static DEFINE_MUTEX(hostaudio_mutex);
67
68/* /dev/dsp file operations */
69
70static ssize_t hostaudio_read(struct file *file, char __user *buffer,
71 size_t count, loff_t *ppos)
72{
73 struct hostaudio_state *state = file->private_data;
74 void *kbuf;
75 int err;
76
77#ifdef DEBUG
78 printk(KERN_DEBUG "hostaudio: read called, count = %d\n", count);
79#endif
80
81 kbuf = kmalloc(count, GFP_KERNEL);
82 if (kbuf == NULL)
83 return -ENOMEM;
84
85 err = os_read_file(state->fd, kbuf, count);
86 if (err < 0)
87 goto out;
88
89 if (copy_to_user(buffer, kbuf, err))
90 err = -EFAULT;
91
92out:
93 kfree(kbuf);
94 return err;
95}
96
97static ssize_t hostaudio_write(struct file *file, const char __user *buffer,
98 size_t count, loff_t *ppos)
99{
100 struct hostaudio_state *state = file->private_data;
101 void *kbuf;
102 int err;
103
104#ifdef DEBUG
105 printk(KERN_DEBUG "hostaudio: write called, count = %d\n", count);
106#endif
107
108 kbuf = memdup_user(buffer, count);
109 if (IS_ERR(kbuf))
110 return PTR_ERR(kbuf);
111
112 err = os_write_file(state->fd, kbuf, count);
113 if (err < 0)
114 goto out;
115 *ppos += err;
116
117 out:
118 kfree(kbuf);
119 return err;
120}
121
122static __poll_t hostaudio_poll(struct file *file,
123 struct poll_table_struct *wait)
124{
125 __poll_t mask = 0;
126
127#ifdef DEBUG
128 printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n");
129#endif
130
131 return mask;
132}
133
134static long hostaudio_ioctl(struct file *file,
135 unsigned int cmd, unsigned long arg)
136{
137 struct hostaudio_state *state = file->private_data;
138 unsigned long data = 0;
139 int err;
140
141#ifdef DEBUG
142 printk(KERN_DEBUG "hostaudio: ioctl called, cmd = %u\n", cmd);
143#endif
144 switch(cmd){
145 case SNDCTL_DSP_SPEED:
146 case SNDCTL_DSP_STEREO:
147 case SNDCTL_DSP_GETBLKSIZE:
148 case SNDCTL_DSP_CHANNELS:
149 case SNDCTL_DSP_SUBDIVIDE:
150 case SNDCTL_DSP_SETFRAGMENT:
151 if (get_user(data, (int __user *) arg))
152 return -EFAULT;
153 break;
154 default:
155 break;
156 }
157
158 err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data);
159
160 switch(cmd){
161 case SNDCTL_DSP_SPEED:
162 case SNDCTL_DSP_STEREO:
163 case SNDCTL_DSP_GETBLKSIZE:
164 case SNDCTL_DSP_CHANNELS:
165 case SNDCTL_DSP_SUBDIVIDE:
166 case SNDCTL_DSP_SETFRAGMENT:
167 if (put_user(data, (int __user *) arg))
168 return -EFAULT;
169 break;
170 default:
171 break;
172 }
173
174 return err;
175}
176
177static int hostaudio_open(struct inode *inode, struct file *file)
178{
179 struct hostaudio_state *state;
180 int r = 0, w = 0;
181 int ret;
182
183#ifdef DEBUG
184 kernel_param_lock(THIS_MODULE);
185 printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp);
186 kernel_param_unlock(THIS_MODULE);
187#endif
188
189 state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
190 if (state == NULL)
191 return -ENOMEM;
192
193 if (file->f_mode & FMODE_READ)
194 r = 1;
195 if (file->f_mode & FMODE_WRITE)
196 w = 1;
197
198 kernel_param_lock(THIS_MODULE);
199 mutex_lock(&hostaudio_mutex);
200 ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
201 mutex_unlock(&hostaudio_mutex);
202 kernel_param_unlock(THIS_MODULE);
203
204 if (ret < 0) {
205 kfree(state);
206 return ret;
207 }
208 state->fd = ret;
209 file->private_data = state;
210 return 0;
211}
212
213static int hostaudio_release(struct inode *inode, struct file *file)
214{
215 struct hostaudio_state *state = file->private_data;
216
217#ifdef DEBUG
218 printk(KERN_DEBUG "hostaudio: release called\n");
219#endif
220 os_close_file(state->fd);
221 kfree(state);
222
223 return 0;
224}
225
226/* /dev/mixer file operations */
227
228static long hostmixer_ioctl_mixdev(struct file *file,
229 unsigned int cmd, unsigned long arg)
230{
231 struct hostmixer_state *state = file->private_data;
232
233#ifdef DEBUG
234 printk(KERN_DEBUG "hostmixer: ioctl called\n");
235#endif
236
237 return os_ioctl_generic(state->fd, cmd, arg);
238}
239
240static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
241{
242 struct hostmixer_state *state;
243 int r = 0, w = 0;
244 int ret;
245
246#ifdef DEBUG
247 printk(KERN_DEBUG "hostmixer: open called (host: %s)\n", mixer);
248#endif
249
250 state = kmalloc(sizeof(struct hostmixer_state), GFP_KERNEL);
251 if (state == NULL)
252 return -ENOMEM;
253
254 if (file->f_mode & FMODE_READ)
255 r = 1;
256 if (file->f_mode & FMODE_WRITE)
257 w = 1;
258
259 kernel_param_lock(THIS_MODULE);
260 mutex_lock(&hostaudio_mutex);
261 ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0);
262 mutex_unlock(&hostaudio_mutex);
263 kernel_param_unlock(THIS_MODULE);
264
265 if (ret < 0) {
266 kernel_param_lock(THIS_MODULE);
267 printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', "
268 "err = %d\n", dsp, -ret);
269 kernel_param_unlock(THIS_MODULE);
270 kfree(state);
271 return ret;
272 }
273
274 file->private_data = state;
275 return 0;
276}
277
278static int hostmixer_release(struct inode *inode, struct file *file)
279{
280 struct hostmixer_state *state = file->private_data;
281
282#ifdef DEBUG
283 printk(KERN_DEBUG "hostmixer: release called\n");
284#endif
285
286 os_close_file(state->fd);
287 kfree(state);
288
289 return 0;
290}
291
292/* kernel module operations */
293
294static const struct file_operations hostaudio_fops = {
295 .owner = THIS_MODULE,
296 .llseek = no_llseek,
297 .read = hostaudio_read,
298 .write = hostaudio_write,
299 .poll = hostaudio_poll,
300 .unlocked_ioctl = hostaudio_ioctl,
301 .compat_ioctl = compat_ptr_ioctl,
302 .mmap = NULL,
303 .open = hostaudio_open,
304 .release = hostaudio_release,
305};
306
307static const struct file_operations hostmixer_fops = {
308 .owner = THIS_MODULE,
309 .llseek = no_llseek,
310 .unlocked_ioctl = hostmixer_ioctl_mixdev,
311 .open = hostmixer_open_mixdev,
312 .release = hostmixer_release,
313};
314
315struct {
316 int dev_audio;
317 int dev_mixer;
318} module_data;
319
320MODULE_AUTHOR("Steve Schmidtke");
321MODULE_DESCRIPTION("UML Audio Relay");
322MODULE_LICENSE("GPL");
323
324static int __init hostaudio_init_module(void)
325{
326 kernel_param_lock(THIS_MODULE);
327 printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
328 dsp, mixer);
329 kernel_param_unlock(THIS_MODULE);
330
331 module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
332 if (module_data.dev_audio < 0) {
333 printk(KERN_ERR "hostaudio: couldn't register DSP device!\n");
334 return -ENODEV;
335 }
336
337 module_data.dev_mixer = register_sound_mixer(&hostmixer_fops, -1);
338 if (module_data.dev_mixer < 0) {
339 printk(KERN_ERR "hostmixer: couldn't register mixer "
340 "device!\n");
341 unregister_sound_dsp(module_data.dev_audio);
342 return -ENODEV;
343 }
344
345 return 0;
346}
347
348static void __exit hostaudio_cleanup_module (void)
349{
350 unregister_sound_mixer(module_data.dev_mixer);
351 unregister_sound_dsp(module_data.dev_audio);
352}
353
354module_init(hostaudio_init_module);
355module_exit(hostaudio_cleanup_module);