fix a possible dead lock in the fonera-mp3 driver, that can happen, when the buffer...
[librecmc/librecmc.git] / package / fonera-mp3-drv / src / mp3_drv.c
1 /*
2 * a.lp_mp3 - VS1011B driver for Fonera 
3 * Copyright (c) 2007 phrozen.org - John Crispin <john@phrozen.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA02111-1307USA
18 *
19 * Feedback, Bugs...  john@phrozen.org 
20 *
21 */
22
23
24 #include <linux/module.h>
25 #include <linux/errno.h>
26 #include <linux/ioport.h>
27 #include <linux/init.h>
28 #include <asm/uaccess.h>
29 #include <asm/io.h>
30 #include <linux/timer.h>
31 #include <linux/init.h>
32 #include <linux/genhd.h>
33 #include <linux/device.h> 
34
35 // do we want debuging info ?
36 #if 0
37 #define DBG(x) x
38 #else
39 #define DBG(x) 
40 #endif
41
42 #define MP3_CHUNK_SIZE                  4096
43 #define MP3_BUFFERING                   0
44 #define MP3_PLAYING                     1
45 #define MP3_BUFFER_FINISHED             2
46 #define MP3_PLAY_FINISHED               3
47 typedef struct _MP3_DATA{
48         unsigned char   mp3[MP3_CHUNK_SIZE];
49         unsigned char state;
50 } MP3_DATA;
51
52 #define IOCTL_MP3_INIT                  0x01
53 #define IOCTL_MP3_RESET                 0x02
54 #define IOCTL_MP3_SETVOLUME             0x03
55 #define IOCTL_MP3_GETVOLUME             0x04
56
57 typedef struct _AUDIO_DATA{
58         unsigned int bitrate;
59         unsigned int sample_rate;
60         unsigned char is_stereo;
61 }AUDIO_DATA;
62 #define IOCTL_MP3_GETAUDIODATA          0x05
63 #define IOCTL_MP3_CLEARBUFFER           0x06
64 #define IOCTL_MP3_PLAY                  0x07
65
66 typedef struct _MP3_BEEP{
67         unsigned char   freq;
68         unsigned int    ms;
69 } MP3_BEEP;
70 #define IOCTL_MP3_BEEP                  0x08                    
71 #define IOCTL_MP3_END_REACHED           0x09
72 #define IOCTL_MP3_BASS                  0x10
73
74 #define CRYSTAL12288    0x9800
75 #define CRYSTAL24576    0x0
76
77 #define DEV_NAME                        "mp3"
78 #define DEV_MAJOR                       196
79 #define MAX_MP3_COUNT   1
80
81 typedef struct _mp3_inf{
82         unsigned char is_open;
83 } mp3_inf;
84 static mp3_inf mp3_info[MAX_MP3_COUNT];
85
86 #define MP3_BUFFER_SIZE         (128 * 1024)
87 unsigned char mp3_buffer[MP3_BUFFER_SIZE];
88
89 static unsigned long int mp3_buffer_offset_write = 0;
90 static unsigned long int mp3_buffer_offset_read = 0;
91 static unsigned char mp3_buffering_status = MP3_BUFFERING;
92 static unsigned long int mp3_data_in_buffer = 0;
93 static int mp3_thread = 0;
94 unsigned int crystal_freq;
95
96 #include "vs10xx.c"
97
98 static wait_queue_head_t wq;
99 static DECLARE_COMPLETION(mp3_exit);
100
101 static int mp3_playback_thread(void *data){
102         int j;
103         unsigned long timeout;
104         unsigned char empty = 0;
105         printk("started kthread\n");
106         daemonize("kmp3");
107         while(mp3_buffering_status != MP3_PLAY_FINISHED){
108                 if((mp3_buffering_status == MP3_PLAYING) || (mp3_buffering_status == MP3_BUFFER_FINISHED)){
109                         while((VS1011_NEEDS_DATA) && (!empty)){
110                                 if(mp3_buffer_offset_read == MP3_BUFFER_SIZE){
111                                         mp3_buffer_offset_read = 0;
112                                 }
113                                 
114                                 if(mp3_data_in_buffer == 0){
115                                         if(mp3_buffering_status == MP3_BUFFER_FINISHED){
116                                                 printk("mp3_drv.ko : finished playing\n");
117                                                 mp3_buffering_status = MP3_PLAY_FINISHED;
118                                         } else {
119                                                 empty = 1;
120                                                 printk("mp3_drv.ko : buffer empty ?\n");
121                                                 if(mp3_buffering_status != MP3_PLAY_FINISHED){
122                                                 }
123                                         }
124                                 } else {
125                                         for(j = 0; j < 32; j++){
126                                                 VS1011_send_SDI(mp3_buffer[mp3_buffer_offset_read + j]);
127                                         }
128                                         mp3_buffer_offset_read += 32;
129                                         mp3_data_in_buffer -= 32;
130                                 }
131                         }
132                 }
133                 empty = 0;
134                 timeout = 1;    
135         timeout = wait_event_interruptible_timeout(wq, (timeout==0), timeout);  
136         }
137         complete_and_exit(&mp3_exit, 0); 
138 }
139
140 static ssize_t module_write(struct file * file, const char * buffer, size_t count, loff_t *offset){
141         MP3_DATA mp3_data;
142         
143         copy_from_user((char*) &mp3_data, buffer, sizeof(MP3_DATA));
144         
145         if(mp3_data.state == MP3_BUFFER_FINISHED){
146                 mp3_buffering_status = MP3_BUFFER_FINISHED;
147                 DBG(printk("mp3_drv.ko : file end reached\n"));
148                 return 1;
149         }
150         
151         if(mp3_data.state == MP3_PLAY_FINISHED){
152                 mp3_buffering_status = MP3_PLAY_FINISHED;
153                 mp3_data_in_buffer = 0;
154                 DBG(printk("mp3_drv.ko : stop playing\n"));
155                 return 1;
156         }
157         
158         if(mp3_data_in_buffer + MP3_CHUNK_SIZE >= MP3_BUFFER_SIZE){
159                 DBG(printk("mp3_drv.ko : buffer is full? %ld\n", mp3_data_in_buffer);)
160                 return 0;
161         }
162         
163         if(mp3_buffer_offset_write == MP3_BUFFER_SIZE){
164                 mp3_buffer_offset_write = 0;
165         }
166         
167         memcpy(&mp3_buffer[mp3_buffer_offset_write], mp3_data.mp3, MP3_CHUNK_SIZE);
168         mp3_buffer_offset_write += MP3_CHUNK_SIZE;
169         mp3_buffering_status = mp3_data.state;
170         mp3_data_in_buffer += MP3_CHUNK_SIZE;
171         return 1;
172 }
173
174 static int module_ioctl(struct inode * inode, struct file * file, unsigned int cmd, unsigned long arg){
175         unsigned int    retval = 0;
176         AUDIO_DATA      audio_data;
177         MP3_BEEP        mp3_beep;
178         DBG(printk("mp3_drv.ko : Ioctl Called (cmd=%d)\n", cmd );)
179         switch (cmd) {
180                 case IOCTL_MP3_INIT:
181                         crystal_freq = arg;
182                         VS1011_init(crystal_freq, 1);
183                         VS1011_print_registers();
184                         break;
185
186                 case IOCTL_MP3_RESET:
187                         DBG(printk("mp3_drv.ko : doing a sw reset\n");)
188                         VS1011_init(crystal_freq, 0);
189                         VS1011_print_registers();
190                         VS1011_send_zeros(0x20);
191                         break;
192
193                 case IOCTL_MP3_SETVOLUME:
194                         DBG(printk("mp3_drv.ko : setting volume to : %lu\n", arg&0xffff);)
195                         VS1011_set_volume(arg);
196                         break;
197
198                 case IOCTL_MP3_GETVOLUME:
199                         retval = VS1011_get_volume();
200                         DBG(printk("mp3_drv.ko : read volume : %d\n", retval);)
201                         break;
202
203                 case IOCTL_MP3_GETAUDIODATA:
204                         DBG(printk("mp3_drv.ko : read audio data\n");)
205                         VS1011_get_audio_data(&audio_data);
206                         copy_to_user((char*)arg, (char*)&audio_data, sizeof(AUDIO_DATA));
207                         break;
208
209                 case IOCTL_MP3_CLEARBUFFER:
210                         DBG(printk("mp3_drv.ko : clearing buffer\n");)
211                         mp3_buffer_offset_read = 0;
212                         mp3_buffer_offset_write = 0;
213                         mp3_buffering_status = MP3_PLAY_FINISHED;
214                         mp3_data_in_buffer = 0;
215                         break;
216
217                 case IOCTL_MP3_PLAY:
218                         mp3_thread = kernel_thread(mp3_playback_thread, NULL, CLONE_KERNEL);
219                         break;
220
221                 case IOCTL_MP3_BEEP:
222                         copy_from_user((char*)&mp3_beep, (char*)arg, sizeof(MP3_BEEP));
223                         VS1011_sine(1,mp3_beep.freq);
224                         msDelay(mp3_beep.ms);
225                         VS1011_sine(0,0);
226                         break;
227
228                 case IOCTL_MP3_END_REACHED:
229                         if(mp3_buffering_status == MP3_PLAY_FINISHED){
230                                 retval = 1;
231                         }
232                         break;
233
234                 case IOCTL_MP3_BASS:
235                         VS1011_set_bass(arg);
236                         break;
237
238                 default:
239                         printk("mp3_drv.ko : unknown ioctl\n");
240                         break;
241
242         }
243         return retval;
244 }
245
246 static int module_open(struct inode *inode, struct file *file){
247         unsigned int dev_minor = MINOR(inode->i_rdev);
248         if(dev_minor !=  0){
249                 printk("mp3_drv.ko : trying to access unknown minor device -> %d\n", dev_minor);
250                 return -ENODEV;
251         }
252         if(mp3_info[dev_minor].is_open) {
253                 printk("mp3_drv.ko : Device with minor ID %d already in use\n", dev_minor);
254                 return -EBUSY;
255         }
256         mp3_info[dev_minor].is_open = 1;
257         
258         mp3_buffering_status = MP3_PLAY_FINISHED;
259         printk("mp3_drv.ko : Minor %d has been opened\n", dev_minor);
260         return 0;
261 }
262
263 static int module_close(struct inode * inode, struct file * file){
264         unsigned int dev_minor = MINOR(inode->i_rdev);
265         mp3_info[dev_minor].is_open = 0;
266         printk("mp3_drv.ko : Minor %d has been closed\n", dev_minor);
267         mp3_buffering_status = MP3_PLAY_FINISHED;
268         return 0;
269 }
270
271 struct file_operations modulemp3_fops = {
272         write:         module_write,
273         ioctl:         module_ioctl,
274         open:          module_open,
275         release:       module_close
276 };
277
278 static struct class *mp3_class; 
279
280 static int __init mod_init(void){
281         printk("mp3_drv.ko : VS1011b Driver\n");
282         printk("mp3_drv.ko : Made by John '2B|!2B' Crispin (john@phrozen.org)\n");
283         printk("mp3_drv.ko : Starting ...\n");
284         
285         if(register_chrdev(DEV_MAJOR, DEV_NAME, &modulemp3_fops)) {
286                 printk( "mp3_drv.ko : Error whilst opening %s (%d)\n", DEV_NAME, DEV_MAJOR);
287                 return( -ENODEV );
288         }
289
290         printk("mp3_drv.ko : using sysfs to create device nodes\n");
291         mp3_class = class_create(THIS_MODULE, DEV_NAME); 
292         class_device_create(mp3_class, NULL, 
293                 MKDEV(DEV_MAJOR, 0), 
294                 NULL, DEV_NAME); 
295
296         mp3_info[0].is_open = 0;
297         printk("mp3_drv.ko : Device %s registered for major ID %d\n", DEV_NAME, DEV_MAJOR);
298         crystal_freq = CRYSTAL12288;
299         VS1011_init(crystal_freq, 1);
300         VS1011_print_registers();
301         printk("end of init\n");
302         init_waitqueue_head(&wq);
303         printk("wait queue started\n");
304         return 0;
305 }
306
307 static void __exit mod_exit(void){
308         printk( "mp3_drv.ko : Cleanup\n" );
309         unregister_chrdev(DEV_MAJOR, DEV_NAME);
310 }
311
312 module_init (mod_init);
313 module_exit (mod_exit);
314
315 MODULE_LICENSE("GPL");
316 MODULE_AUTHOR("K. John '2B|!2B' Crispin");
317 MODULE_DESCRIPTION("vs1011 Driver for Fox Board");
318
319
320