xref: /openbmc/linux/arch/um/drivers/hostaudio_kern.c (revision 64c70b1c)
1 /*
2  * Copyright (C) 2002 Steve Schmidtke
3  * Licensed under the GPL
4  */
5 
6 #include "linux/module.h"
7 #include "linux/init.h"
8 #include "linux/slab.h"
9 #include "linux/fs.h"
10 #include "linux/sound.h"
11 #include "linux/soundcard.h"
12 #include "asm/uaccess.h"
13 #include "kern_util.h"
14 #include "init.h"
15 #include "os.h"
16 
17 struct hostaudio_state {
18 	int fd;
19 };
20 
21 struct hostmixer_state {
22 	int fd;
23 };
24 
25 #define HOSTAUDIO_DEV_DSP "/dev/sound/dsp"
26 #define HOSTAUDIO_DEV_MIXER "/dev/sound/mixer"
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 #ifndef MODULE
44 static int set_dsp(char *name, int *add)
45 {
46 	dsp = name;
47 	return(0);
48 }
49 
50 __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
51 
52 static int set_mixer(char *name, int *add)
53 {
54 	mixer = name;
55 	return(0);
56 }
57 
58 __uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
59 
60 #else /*MODULE*/
61 
62 module_param(dsp, charp, 0644);
63 MODULE_PARM_DESC(dsp, DSP_HELP);
64 
65 module_param(mixer, charp, 0644);
66 MODULE_PARM_DESC(mixer, MIXER_HELP);
67 
68 #endif
69 
70 /* /dev/dsp file operations */
71 
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("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 
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("hostaudio: write called, count = %d\n", count);
108 #endif
109 
110 	kbuf = kmalloc(count, GFP_KERNEL);
111 	if(kbuf == NULL)
112 		return(-ENOMEM);
113 
114 	err = -EFAULT;
115 	if(copy_from_user(kbuf, buffer, count))
116 		goto out;
117 
118 	err = os_write_file(state->fd, kbuf, count);
119 	if(err < 0)
120 		goto out;
121 	*ppos += err;
122 
123  out:
124 	kfree(kbuf);
125 	return(err);
126 }
127 
128 static unsigned int hostaudio_poll(struct file *file,
129 				   struct poll_table_struct *wait)
130 {
131 	unsigned int mask = 0;
132 
133 #ifdef DEBUG
134 	printk("hostaudio: poll called (unimplemented)\n");
135 #endif
136 
137 	return(mask);
138 }
139 
140 static int hostaudio_ioctl(struct inode *inode, struct file *file,
141 			   unsigned int cmd, unsigned long arg)
142 {
143 	struct hostaudio_state *state = file->private_data;
144 	unsigned long data = 0;
145 	int err;
146 
147 #ifdef DEBUG
148 	printk("hostaudio: ioctl called, cmd = %u\n", cmd);
149 #endif
150 	switch(cmd){
151 	case SNDCTL_DSP_SPEED:
152 	case SNDCTL_DSP_STEREO:
153 	case SNDCTL_DSP_GETBLKSIZE:
154 	case SNDCTL_DSP_CHANNELS:
155 	case SNDCTL_DSP_SUBDIVIDE:
156 	case SNDCTL_DSP_SETFRAGMENT:
157 		if(get_user(data, (int __user *) arg))
158 			return(-EFAULT);
159 		break;
160 	default:
161 		break;
162 	}
163 
164 	err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data);
165 
166 	switch(cmd){
167 	case SNDCTL_DSP_SPEED:
168 	case SNDCTL_DSP_STEREO:
169 	case SNDCTL_DSP_GETBLKSIZE:
170 	case SNDCTL_DSP_CHANNELS:
171 	case SNDCTL_DSP_SUBDIVIDE:
172 	case SNDCTL_DSP_SETFRAGMENT:
173 		if(put_user(data, (int __user *) arg))
174 			return(-EFAULT);
175 		break;
176 	default:
177 		break;
178 	}
179 
180 	return(err);
181 }
182 
183 static int hostaudio_open(struct inode *inode, struct file *file)
184 {
185 	struct hostaudio_state *state;
186 	int r = 0, w = 0;
187 	int ret;
188 
189 #ifdef DEBUG
190 	printk("hostaudio: open called (host: %s)\n", dsp);
191 #endif
192 
193 	state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
194 	if(state == NULL)
195 		return(-ENOMEM);
196 
197 	if(file->f_mode & FMODE_READ) r = 1;
198 	if(file->f_mode & FMODE_WRITE) w = 1;
199 
200 	ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
201 	if(ret < 0){
202 		kfree(state);
203 		return(ret);
204 	}
205 	state->fd = ret;
206 	file->private_data = state;
207 	return(0);
208 }
209 
210 static int hostaudio_release(struct inode *inode, struct file *file)
211 {
212 	struct hostaudio_state *state = file->private_data;
213 
214 #ifdef DEBUG
215 	printk("hostaudio: release called\n");
216 #endif
217 	os_close_file(state->fd);
218 	kfree(state);
219 
220 	return(0);
221 }
222 
223 /* /dev/mixer file operations */
224 
225 static int hostmixer_ioctl_mixdev(struct inode *inode, struct file *file,
226 				  unsigned int cmd, unsigned long arg)
227 {
228 	struct hostmixer_state *state = file->private_data;
229 
230 #ifdef DEBUG
231 	printk("hostmixer: ioctl called\n");
232 #endif
233 
234 	return(os_ioctl_generic(state->fd, cmd, arg));
235 }
236 
237 static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
238 {
239 	struct hostmixer_state *state;
240 	int r = 0, w = 0;
241 	int ret;
242 
243 #ifdef DEBUG
244 	printk("hostmixer: open called (host: %s)\n", mixer);
245 #endif
246 
247 	state = kmalloc(sizeof(struct hostmixer_state), GFP_KERNEL);
248 	if(state == NULL) return(-ENOMEM);
249 
250 	if(file->f_mode & FMODE_READ) r = 1;
251 	if(file->f_mode & FMODE_WRITE) w = 1;
252 
253 	ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0);
254 
255 	if(ret < 0){
256 		printk("hostaudio_open_mixdev failed to open '%s', err = %d\n",
257 		       dsp, -ret);
258 		kfree(state);
259 		return(ret);
260 	}
261 
262 	file->private_data = state;
263 	return(0);
264 }
265 
266 static int hostmixer_release(struct inode *inode, struct file *file)
267 {
268 	struct hostmixer_state *state = file->private_data;
269 
270 #ifdef DEBUG
271 	printk("hostmixer: release called\n");
272 #endif
273 
274 	os_close_file(state->fd);
275 	kfree(state);
276 
277 	return(0);
278 }
279 
280 /* kernel module operations */
281 
282 static const struct file_operations hostaudio_fops = {
283 	.owner          = THIS_MODULE,
284 	.llseek         = no_llseek,
285 	.read           = hostaudio_read,
286 	.write          = hostaudio_write,
287 	.poll           = hostaudio_poll,
288 	.ioctl          = hostaudio_ioctl,
289 	.mmap           = NULL,
290 	.open           = hostaudio_open,
291 	.release        = hostaudio_release,
292 };
293 
294 static const struct file_operations hostmixer_fops = {
295 	.owner          = THIS_MODULE,
296 	.llseek         = no_llseek,
297 	.ioctl          = hostmixer_ioctl_mixdev,
298 	.open           = hostmixer_open_mixdev,
299 	.release        = hostmixer_release,
300 };
301 
302 struct {
303 	int dev_audio;
304 	int dev_mixer;
305 } module_data;
306 
307 MODULE_AUTHOR("Steve Schmidtke");
308 MODULE_DESCRIPTION("UML Audio Relay");
309 MODULE_LICENSE("GPL");
310 
311 static int __init hostaudio_init_module(void)
312 {
313 	printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
314 	       dsp, mixer);
315 
316 	module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
317 	if(module_data.dev_audio < 0){
318 		printk(KERN_ERR "hostaudio: couldn't register DSP device!\n");
319 		return -ENODEV;
320 	}
321 
322 	module_data.dev_mixer = register_sound_mixer(&hostmixer_fops, -1);
323 	if(module_data.dev_mixer < 0){
324 		printk(KERN_ERR "hostmixer: couldn't register mixer "
325 		       "device!\n");
326 		unregister_sound_dsp(module_data.dev_audio);
327 		return -ENODEV;
328 	}
329 
330 	return 0;
331 }
332 
333 static void __exit hostaudio_cleanup_module (void)
334 {
335 	unregister_sound_mixer(module_data.dev_mixer);
336 	unregister_sound_dsp(module_data.dev_audio);
337 }
338 
339 module_init(hostaudio_init_module);
340 module_exit(hostaudio_cleanup_module);
341