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
16 struct hostaudio_state {
17 int fd;
18 };
19
20 struct 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 */
32 static char *dsp = HOSTAUDIO_DEV_DSP;
33 static 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
43 module_param(dsp, charp, 0644);
44 MODULE_PARM_DESC(dsp, DSP_HELP);
45 module_param(mixer, charp, 0644);
46 MODULE_PARM_DESC(mixer, MIXER_HELP);
47
48 #ifndef MODULE
set_dsp(char * name,int * add)49 static int set_dsp(char *name, int *add)
50 {
51 *add = 0;
52 dsp = name;
53 return 0;
54 }
55
56 __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
57
set_mixer(char * name,int * add)58 static int set_mixer(char *name, int *add)
59 {
60 *add = 0;
61 mixer = name;
62 return 0;
63 }
64
65 __uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
66 #endif
67
68 static DEFINE_MUTEX(hostaudio_mutex);
69
70 /* /dev/dsp file operations */
71
hostaudio_read(struct file * file,char __user * buffer,size_t count,loff_t * ppos)72 static ssize_t hostaudio_read(struct file *file, char __user *buffer,
73 size_t count, loff_t *ppos)
74 {
75 struct hostaudio_state *state = file->private_data;
76 void *kbuf;
77 int err;
78
79 #ifdef DEBUG
80 printk(KERN_DEBUG "hostaudio: read called, count = %d\n", count);
81 #endif
82
83 kbuf = kmalloc(count, GFP_KERNEL);
84 if (kbuf == NULL)
85 return -ENOMEM;
86
87 err = os_read_file(state->fd, kbuf, count);
88 if (err < 0)
89 goto out;
90
91 if (copy_to_user(buffer, kbuf, err))
92 err = -EFAULT;
93
94 out:
95 kfree(kbuf);
96 return err;
97 }
98
hostaudio_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)99 static ssize_t hostaudio_write(struct file *file, const char __user *buffer,
100 size_t count, loff_t *ppos)
101 {
102 struct hostaudio_state *state = file->private_data;
103 void *kbuf;
104 int err;
105
106 #ifdef DEBUG
107 printk(KERN_DEBUG "hostaudio: write called, count = %d\n", count);
108 #endif
109
110 kbuf = memdup_user(buffer, count);
111 if (IS_ERR(kbuf))
112 return PTR_ERR(kbuf);
113
114 err = os_write_file(state->fd, kbuf, count);
115 if (err < 0)
116 goto out;
117 *ppos += err;
118
119 out:
120 kfree(kbuf);
121 return err;
122 }
123
hostaudio_poll(struct file * file,struct poll_table_struct * wait)124 static __poll_t hostaudio_poll(struct file *file,
125 struct poll_table_struct *wait)
126 {
127 #ifdef DEBUG
128 printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n");
129 #endif
130
131 return 0;
132 }
133
hostaudio_ioctl(struct file * file,unsigned int cmd,unsigned long arg)134 static 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
hostaudio_open(struct inode * inode,struct file * file)177 static 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
hostaudio_release(struct inode * inode,struct file * file)213 static 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
hostmixer_ioctl_mixdev(struct file * file,unsigned int cmd,unsigned long arg)228 static 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
hostmixer_open_mixdev(struct inode * inode,struct file * file)240 static 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
hostmixer_release(struct inode * inode,struct file * file)278 static 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
294 static const struct file_operations hostaudio_fops = {
295 .owner = THIS_MODULE,
296 .read = hostaudio_read,
297 .write = hostaudio_write,
298 .poll = hostaudio_poll,
299 .unlocked_ioctl = hostaudio_ioctl,
300 .compat_ioctl = compat_ptr_ioctl,
301 .mmap = NULL,
302 .open = hostaudio_open,
303 .release = hostaudio_release,
304 };
305
306 static const struct file_operations hostmixer_fops = {
307 .owner = THIS_MODULE,
308 .unlocked_ioctl = hostmixer_ioctl_mixdev,
309 .open = hostmixer_open_mixdev,
310 .release = hostmixer_release,
311 };
312
313 static struct {
314 int dev_audio;
315 int dev_mixer;
316 } module_data;
317
318 MODULE_AUTHOR("Steve Schmidtke");
319 MODULE_DESCRIPTION("UML Audio Relay");
320 MODULE_LICENSE("GPL");
321
hostaudio_init_module(void)322 static int __init hostaudio_init_module(void)
323 {
324 kernel_param_lock(THIS_MODULE);
325 printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
326 dsp, mixer);
327 kernel_param_unlock(THIS_MODULE);
328
329 module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
330 if (module_data.dev_audio < 0) {
331 printk(KERN_ERR "hostaudio: couldn't register DSP device!\n");
332 return -ENODEV;
333 }
334
335 module_data.dev_mixer = register_sound_mixer(&hostmixer_fops, -1);
336 if (module_data.dev_mixer < 0) {
337 printk(KERN_ERR "hostmixer: couldn't register mixer "
338 "device!\n");
339 unregister_sound_dsp(module_data.dev_audio);
340 return -ENODEV;
341 }
342
343 return 0;
344 }
345
hostaudio_cleanup_module(void)346 static void __exit hostaudio_cleanup_module (void)
347 {
348 unregister_sound_mixer(module_data.dev_mixer);
349 unregister_sound_dsp(module_data.dev_audio);
350 }
351
352 module_init(hostaudio_init_module);
353 module_exit(hostaudio_cleanup_module);
354