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#ifdef DEBUG
126	printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n");
127#endif
128
129	return 0;
130}
131
132static 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
175static 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(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(&hostaudio_mutex);
200	kernel_param_unlock(THIS_MODULE);
201
202	if (ret < 0) {
203		kfree(state);
204		return ret;
205	}
206	state->fd = ret;
207	file->private_data = state;
208	return 0;
209}
210
211static 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(state);
220
221	return 0;
222}
223
224/* /dev/mixer file operations */
225
226static 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
238static 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(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(&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(state);
269		return ret;
270	}
271
272	file->private_data = state;
273	return 0;
274}
275
276static 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(state);
286
287	return 0;
288}
289
290/* kernel module operations */
291
292static 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
305static 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
313static struct {
314	int dev_audio;
315	int dev_mixer;
316} module_data;
317
318MODULE_AUTHOR("Steve Schmidtke");
319MODULE_DESCRIPTION("UML Audio Relay");
320MODULE_LICENSE("GPL");
321
322static 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
346static 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
352module_init(hostaudio_init_module);
353module_exit(hostaudio_cleanup_module);
354