1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2002 Steve Schmidtke
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>
16 struct hostaudio_state {
20 struct hostmixer_state {
24 #define HOSTAUDIO_DEV_DSP "/dev/sound/dsp"
25 #define HOSTAUDIO_DEV_MIXER "/dev/sound/mixer"
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.
32 static char *dsp = HOSTAUDIO_DEV_DSP;
33 static char *mixer = HOSTAUDIO_DEV_MIXER;
36 " This is used to specify the host dsp device to the hostaudio driver.\n" \
37 " The default is \"" HOSTAUDIO_DEV_DSP "\".\n\n"
40 " This is used to specify the host mixer device to the hostaudio driver.\n"\
41 " The default is \"" HOSTAUDIO_DEV_MIXER "\".\n\n"
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);
49 static int set_dsp(char *name, int *add)
55 __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
57 static int set_mixer(char *name, int *add)
63 __uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
66 static DEFINE_MUTEX(hostaudio_mutex);
68 /* /dev/dsp file operations */
70 static ssize_t hostaudio_read(struct file *file, char __user *buffer,
71 size_t count, loff_t *ppos)
73 struct hostaudio_state *state = file->private_data;
78 printk(KERN_DEBUG "hostaudio: read called, count = %d\n", count);
81 kbuf = kmalloc(count, GFP_KERNEL);
85 err = os_read_file(state->fd, kbuf, count);
89 if (copy_to_user(buffer, kbuf, err))
97 static ssize_t hostaudio_write(struct file *file, const char __user *buffer,
98 size_t count, loff_t *ppos)
100 struct hostaudio_state *state = file->private_data;
105 printk(KERN_DEBUG "hostaudio: write called, count = %d\n", count);
108 kbuf = memdup_user(buffer, count);
110 return PTR_ERR(kbuf);
112 err = os_write_file(state->fd, kbuf, count);
122 static __poll_t hostaudio_poll(struct file *file,
123 struct poll_table_struct *wait)
126 printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n");
132 static long hostaudio_ioctl(struct file *file,
133 unsigned int cmd, unsigned long arg)
135 struct hostaudio_state *state = file->private_data;
136 unsigned long data = 0;
140 printk(KERN_DEBUG "hostaudio: ioctl called, cmd = %u\n", 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))
156 err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data);
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))
175 static int hostaudio_open(struct inode *inode, struct file *file)
177 struct hostaudio_state *state;
182 kernel_param_lock(THIS_MODULE);
183 printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp);
184 kernel_param_unlock(THIS_MODULE);
187 state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
191 if (file->f_mode & FMODE_READ)
193 if (file->f_mode & FMODE_WRITE)
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(&hostaudio_mutex);
200 kernel_param_unlock(THIS_MODULE);
207 file->private_data = state;
211 static int hostaudio_release(struct inode *inode, struct file *file)
213 struct hostaudio_state *state = file->private_data;
216 printk(KERN_DEBUG "hostaudio: release called\n");
218 os_close_file(state->fd);
224 /* /dev/mixer file operations */
226 static long hostmixer_ioctl_mixdev(struct file *file,
227 unsigned int cmd, unsigned long arg)
229 struct hostmixer_state *state = file->private_data;
232 printk(KERN_DEBUG "hostmixer: ioctl called\n");
235 return os_ioctl_generic(state->fd, cmd, arg);
238 static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
240 struct hostmixer_state *state;
245 printk(KERN_DEBUG "hostmixer: open called (host: %s)\n", mixer);
248 state = kmalloc(sizeof(struct hostmixer_state), GFP_KERNEL);
252 if (file->f_mode & FMODE_READ)
254 if (file->f_mode & FMODE_WRITE)
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(&hostaudio_mutex);
261 kernel_param_unlock(THIS_MODULE);
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);
272 file->private_data = state;
276 static int hostmixer_release(struct inode *inode, struct file *file)
278 struct hostmixer_state *state = file->private_data;
281 printk(KERN_DEBUG "hostmixer: release called\n");
284 os_close_file(state->fd);
290 /* kernel module operations */
292 static const struct file_operations hostaudio_fops = {
293 .owner = THIS_MODULE,
295 .read = hostaudio_read,
296 .write = hostaudio_write,
297 .poll = hostaudio_poll,
298 .unlocked_ioctl = hostaudio_ioctl,
299 .compat_ioctl = compat_ptr_ioctl,
301 .open = hostaudio_open,
302 .release = hostaudio_release,
305 static const struct file_operations hostmixer_fops = {
306 .owner = THIS_MODULE,
308 .unlocked_ioctl = hostmixer_ioctl_mixdev,
309 .open = hostmixer_open_mixdev,
310 .release = hostmixer_release,
318 MODULE_AUTHOR("Steve Schmidtke");
319 MODULE_DESCRIPTION("UML Audio Relay");
320 MODULE_LICENSE("GPL");
322 static int __init hostaudio_init_module(void)
324 kernel_param_lock(THIS_MODULE);
325 printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
327 kernel_param_unlock(THIS_MODULE);
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");
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 "
339 unregister_sound_dsp(module_data.dev_audio);
346 static void __exit hostaudio_cleanup_module (void)
348 unregister_sound_mixer(module_data.dev_mixer);
349 unregister_sound_dsp(module_data.dev_audio);
352 module_init(hostaudio_init_module);
353 module_exit(hostaudio_cleanup_module);