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 |
49 | static 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 | |
57 | static 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 | |
66 | static DEFINE_MUTEX(hostaudio_mutex); |
67 | |
68 | /* /dev/dsp file operations */ |
69 | |
70 | static 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(size: 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(to: buffer, from: kbuf, n: err)) |
90 | err = -EFAULT; |
91 | |
92 | out: |
93 | kfree(objp: kbuf); |
94 | return err; |
95 | } |
96 | |
97 | static 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(ptr: kbuf)) |
110 | return PTR_ERR(ptr: 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(objp: kbuf); |
119 | return err; |
120 | } |
121 | |
122 | static __poll_t hostaudio_poll(struct file *file, |
123 | struct poll_table_struct *wait) |
124 | { |
125 | #ifdef DEBUG |
126 | printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n" ); |
127 | #endif |
128 | |
129 | return 0; |
130 | } |
131 | |
132 | static long hostaudio_ioctl(struct file *file, |
133 | unsigned int cmd, unsigned long arg) |
134 | { |
135 | struct hostaudio_state *state = file->private_data; |
136 | unsigned long data = 0; |
137 | int err; |
138 | |
139 | #ifdef DEBUG |
140 | printk(KERN_DEBUG "hostaudio: ioctl called, cmd = %u\n" , cmd); |
141 | #endif |
142 | switch(cmd){ |
143 | case SNDCTL_DSP_SPEED: |
144 | case SNDCTL_DSP_STEREO: |
145 | case SNDCTL_DSP_GETBLKSIZE: |
146 | case SNDCTL_DSP_CHANNELS: |
147 | case SNDCTL_DSP_SUBDIVIDE: |
148 | case SNDCTL_DSP_SETFRAGMENT: |
149 | if (get_user(data, (int __user *) arg)) |
150 | return -EFAULT; |
151 | break; |
152 | default: |
153 | break; |
154 | } |
155 | |
156 | err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data); |
157 | |
158 | switch(cmd){ |
159 | case SNDCTL_DSP_SPEED: |
160 | case SNDCTL_DSP_STEREO: |
161 | case SNDCTL_DSP_GETBLKSIZE: |
162 | case SNDCTL_DSP_CHANNELS: |
163 | case SNDCTL_DSP_SUBDIVIDE: |
164 | case SNDCTL_DSP_SETFRAGMENT: |
165 | if (put_user(data, (int __user *) arg)) |
166 | return -EFAULT; |
167 | break; |
168 | default: |
169 | break; |
170 | } |
171 | |
172 | return err; |
173 | } |
174 | |
175 | static int hostaudio_open(struct inode *inode, struct file *file) |
176 | { |
177 | struct hostaudio_state *state; |
178 | int r = 0, w = 0; |
179 | int ret; |
180 | |
181 | #ifdef DEBUG |
182 | kernel_param_lock(THIS_MODULE); |
183 | printk(KERN_DEBUG "hostaudio: open called (host: %s)\n" , dsp); |
184 | kernel_param_unlock(THIS_MODULE); |
185 | #endif |
186 | |
187 | state = kmalloc(size: sizeof(struct hostaudio_state), GFP_KERNEL); |
188 | if (state == NULL) |
189 | return -ENOMEM; |
190 | |
191 | if (file->f_mode & FMODE_READ) |
192 | r = 1; |
193 | if (file->f_mode & FMODE_WRITE) |
194 | w = 1; |
195 | |
196 | kernel_param_lock(THIS_MODULE); |
197 | mutex_lock(&hostaudio_mutex); |
198 | ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0); |
199 | mutex_unlock(lock: &hostaudio_mutex); |
200 | kernel_param_unlock(THIS_MODULE); |
201 | |
202 | if (ret < 0) { |
203 | kfree(objp: state); |
204 | return ret; |
205 | } |
206 | state->fd = ret; |
207 | file->private_data = state; |
208 | return 0; |
209 | } |
210 | |
211 | static int hostaudio_release(struct inode *inode, struct file *file) |
212 | { |
213 | struct hostaudio_state *state = file->private_data; |
214 | |
215 | #ifdef DEBUG |
216 | printk(KERN_DEBUG "hostaudio: release called\n" ); |
217 | #endif |
218 | os_close_file(state->fd); |
219 | kfree(objp: state); |
220 | |
221 | return 0; |
222 | } |
223 | |
224 | /* /dev/mixer file operations */ |
225 | |
226 | static long hostmixer_ioctl_mixdev(struct file *file, |
227 | unsigned int cmd, unsigned long arg) |
228 | { |
229 | struct hostmixer_state *state = file->private_data; |
230 | |
231 | #ifdef DEBUG |
232 | printk(KERN_DEBUG "hostmixer: ioctl called\n" ); |
233 | #endif |
234 | |
235 | return os_ioctl_generic(state->fd, cmd, arg); |
236 | } |
237 | |
238 | static int hostmixer_open_mixdev(struct inode *inode, struct file *file) |
239 | { |
240 | struct hostmixer_state *state; |
241 | int r = 0, w = 0; |
242 | int ret; |
243 | |
244 | #ifdef DEBUG |
245 | printk(KERN_DEBUG "hostmixer: open called (host: %s)\n" , mixer); |
246 | #endif |
247 | |
248 | state = kmalloc(size: sizeof(struct hostmixer_state), GFP_KERNEL); |
249 | if (state == NULL) |
250 | return -ENOMEM; |
251 | |
252 | if (file->f_mode & FMODE_READ) |
253 | r = 1; |
254 | if (file->f_mode & FMODE_WRITE) |
255 | w = 1; |
256 | |
257 | kernel_param_lock(THIS_MODULE); |
258 | mutex_lock(&hostaudio_mutex); |
259 | ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0); |
260 | mutex_unlock(lock: &hostaudio_mutex); |
261 | kernel_param_unlock(THIS_MODULE); |
262 | |
263 | if (ret < 0) { |
264 | kernel_param_lock(THIS_MODULE); |
265 | printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', " |
266 | "err = %d\n" , dsp, -ret); |
267 | kernel_param_unlock(THIS_MODULE); |
268 | kfree(objp: state); |
269 | return ret; |
270 | } |
271 | |
272 | file->private_data = state; |
273 | return 0; |
274 | } |
275 | |
276 | static int hostmixer_release(struct inode *inode, struct file *file) |
277 | { |
278 | struct hostmixer_state *state = file->private_data; |
279 | |
280 | #ifdef DEBUG |
281 | printk(KERN_DEBUG "hostmixer: release called\n" ); |
282 | #endif |
283 | |
284 | os_close_file(state->fd); |
285 | kfree(objp: state); |
286 | |
287 | return 0; |
288 | } |
289 | |
290 | /* kernel module operations */ |
291 | |
292 | static const struct file_operations hostaudio_fops = { |
293 | .owner = THIS_MODULE, |
294 | .llseek = no_llseek, |
295 | .read = hostaudio_read, |
296 | .write = hostaudio_write, |
297 | .poll = hostaudio_poll, |
298 | .unlocked_ioctl = hostaudio_ioctl, |
299 | .compat_ioctl = compat_ptr_ioctl, |
300 | .mmap = NULL, |
301 | .open = hostaudio_open, |
302 | .release = hostaudio_release, |
303 | }; |
304 | |
305 | static const struct file_operations hostmixer_fops = { |
306 | .owner = THIS_MODULE, |
307 | .llseek = no_llseek, |
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 | |
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(fops: &hostaudio_fops, dev: -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(fops: &hostmixer_fops, dev: -1); |
336 | if (module_data.dev_mixer < 0) { |
337 | printk(KERN_ERR "hostmixer: couldn't register mixer " |
338 | "device!\n" ); |
339 | unregister_sound_dsp(unit: module_data.dev_audio); |
340 | return -ENODEV; |
341 | } |
342 | |
343 | return 0; |
344 | } |
345 | |
346 | static void __exit hostaudio_cleanup_module (void) |
347 | { |
348 | unregister_sound_mixer(unit: module_data.dev_mixer); |
349 | unregister_sound_dsp(unit: module_data.dev_audio); |
350 | } |
351 | |
352 | module_init(hostaudio_init_module); |
353 | module_exit(hostaudio_cleanup_module); |
354 | |