sound: OSS: ad1848 - Fix another typo
[linux-2.6.git] / sound / oss / sys_timer.c
1 /*
2  * sound/oss/sys_timer.c
3  *
4  * The default timer for the Level 2 sequencer interface
5  * Uses the (1/HZ sec) timer of kernel.
6  */
7 /*
8  * Copyright (C) by Hannu Savolainen 1993-1997
9  *
10  * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
11  * Version 2 (June 1991). See the "COPYING" file distributed with this software
12  * for more info.
13  */
14 /*
15  * Thomas Sailer   : ioctl code reworked (vmalloc/vfree removed)
16  * Andrew Veliath  : adapted tmr2ticks from level 1 sequencer (avoid overflow)
17  */
18 #include <linux/spinlock.h>
19 #include "sound_config.h"
20
21 static volatile int opened, tmr_running;
22 static volatile time_t tmr_offs, tmr_ctr;
23 static volatile unsigned long ticks_offs;
24 static volatile int curr_tempo, curr_timebase;
25 static volatile unsigned long curr_ticks;
26 static volatile unsigned long next_event_time;
27 static unsigned long prev_event_time;
28
29 static void     poll_def_tmr(unsigned long dummy);
30 static DEFINE_SPINLOCK(lock);
31 static DEFINE_TIMER(def_tmr, poll_def_tmr, 0, 0);
32
33 static unsigned long
34 tmr2ticks(int tmr_value)
35 {
36         /*
37          *    Convert timer ticks to MIDI ticks
38          */
39
40         unsigned long tmp;
41         unsigned long scale;
42
43         /* tmr_value (ticks per sec) *
44            1000000 (usecs per sec) / HZ (ticks per sec) -=> usecs */
45         tmp = tmr_value * (1000000 / HZ);
46         scale = (60 * 1000000) / (curr_tempo * curr_timebase);  /* usecs per MIDI tick */
47         return (tmp + scale / 2) / scale;
48 }
49
50 static void
51 poll_def_tmr(unsigned long dummy)
52 {
53
54         if (opened)
55           {
56
57                   {
58                           def_tmr.expires = (1) + jiffies;
59                           add_timer(&def_tmr);
60                   };
61
62                   if (tmr_running)
63                     {
64                                 spin_lock(&lock);
65                             tmr_ctr++;
66                             curr_ticks = ticks_offs + tmr2ticks(tmr_ctr);
67
68                             if (curr_ticks >= next_event_time)
69                               {
70                                       next_event_time = (unsigned long) -1;
71                                       sequencer_timer(0);
72                               }
73                                 spin_unlock(&lock);
74                     }
75           }
76 }
77
78 static void
79 tmr_reset(void)
80 {
81         unsigned long   flags;
82
83         spin_lock_irqsave(&lock,flags);
84         tmr_offs = 0;
85         ticks_offs = 0;
86         tmr_ctr = 0;
87         next_event_time = (unsigned long) -1;
88         prev_event_time = 0;
89         curr_ticks = 0;
90         spin_unlock_irqrestore(&lock,flags);
91 }
92
93 static int
94 def_tmr_open(int dev, int mode)
95 {
96         if (opened)
97                 return -EBUSY;
98
99         tmr_reset();
100         curr_tempo = 60;
101         curr_timebase = 100;
102         opened = 1;
103
104         ;
105
106         {
107                 def_tmr.expires = (1) + jiffies;
108                 add_timer(&def_tmr);
109         };
110
111         return 0;
112 }
113
114 static void
115 def_tmr_close(int dev)
116 {
117         opened = tmr_running = 0;
118         del_timer(&def_tmr);
119 }
120
121 static int
122 def_tmr_event(int dev, unsigned char *event)
123 {
124         unsigned char   cmd = event[1];
125         unsigned long   parm = *(int *) &event[4];
126
127         switch (cmd)
128           {
129           case TMR_WAIT_REL:
130                   parm += prev_event_time;
131           case TMR_WAIT_ABS:
132                   if (parm > 0)
133                     {
134                             long            time;
135
136                             if (parm <= curr_ticks)     /* It's the time */
137                                     return TIMER_NOT_ARMED;
138
139                             time = parm;
140                             next_event_time = prev_event_time = time;
141
142                             return TIMER_ARMED;
143                     }
144                   break;
145
146           case TMR_START:
147                   tmr_reset();
148                   tmr_running = 1;
149                   break;
150
151           case TMR_STOP:
152                   tmr_running = 0;
153                   break;
154
155           case TMR_CONTINUE:
156                   tmr_running = 1;
157                   break;
158
159           case TMR_TEMPO:
160                   if (parm)
161                     {
162                             if (parm < 8)
163                                     parm = 8;
164                             if (parm > 360)
165                                     parm = 360;
166                             tmr_offs = tmr_ctr;
167                             ticks_offs += tmr2ticks(tmr_ctr);
168                             tmr_ctr = 0;
169                             curr_tempo = parm;
170                     }
171                   break;
172
173           case TMR_ECHO:
174                   seq_copy_to_input(event, 8);
175                   break;
176
177           default:;
178           }
179
180         return TIMER_NOT_ARMED;
181 }
182
183 static unsigned long
184 def_tmr_get_time(int dev)
185 {
186         if (!opened)
187                 return 0;
188
189         return curr_ticks;
190 }
191
192 /* same as sound_timer.c:timer_ioctl!? */
193 static int def_tmr_ioctl(int dev, unsigned int cmd, void __user *arg)
194 {
195         int __user *p = arg;
196         int val;
197
198         switch (cmd) {
199         case SNDCTL_TMR_SOURCE:
200                 return __put_user(TMR_INTERNAL, p);
201
202         case SNDCTL_TMR_START:
203                 tmr_reset();
204                 tmr_running = 1;
205                 return 0;
206
207         case SNDCTL_TMR_STOP:
208                 tmr_running = 0;
209                 return 0;
210
211         case SNDCTL_TMR_CONTINUE:
212                 tmr_running = 1;
213                 return 0;
214
215         case SNDCTL_TMR_TIMEBASE:
216                 if (__get_user(val, p))
217                         return -EFAULT;
218                 if (val) {
219                         if (val < 1)
220                                 val = 1;
221                         if (val > 1000)
222                                 val = 1000;
223                         curr_timebase = val;
224                 }
225                 return __put_user(curr_timebase, p);
226
227         case SNDCTL_TMR_TEMPO:
228                 if (__get_user(val, p))
229                         return -EFAULT;
230                 if (val) {
231                         if (val < 8)
232                                 val = 8;
233                         if (val > 250)
234                                 val = 250;
235                         tmr_offs = tmr_ctr;
236                         ticks_offs += tmr2ticks(tmr_ctr);
237                         tmr_ctr = 0;
238                         curr_tempo = val;
239                         reprogram_timer();
240                 }
241                 return __put_user(curr_tempo, p);
242
243         case SNDCTL_SEQ_CTRLRATE:
244                 if (__get_user(val, p))
245                         return -EFAULT;
246                 if (val != 0)   /* Can't change */
247                         return -EINVAL;
248                 val = ((curr_tempo * curr_timebase) + 30) / 60;
249                 return __put_user(val, p);
250                 
251         case SNDCTL_SEQ_GETTIME:
252                 return __put_user(curr_ticks, p);
253                 
254         case SNDCTL_TMR_METRONOME:
255                 /* NOP */
256                 break;
257                 
258         default:;
259         }
260         return -EINVAL;
261 }
262
263 static void
264 def_tmr_arm(int dev, long time)
265 {
266         if (time < 0)
267                 time = curr_ticks + 1;
268         else if (time <= curr_ticks)    /* It's the time */
269                 return;
270
271         next_event_time = prev_event_time = time;
272
273         return;
274 }
275
276 struct sound_timer_operations default_sound_timer =
277 {
278         .owner          = THIS_MODULE,
279         .info           = {"System clock", 0},
280         .priority       = 0,    /* Priority */
281         .devlink        = 0,    /* Local device link */
282         .open           = def_tmr_open,
283         .close          = def_tmr_close,
284         .event          = def_tmr_event,
285         .get_time       = def_tmr_get_time,
286         .ioctl          = def_tmr_ioctl,
287         .arm_timer      = def_tmr_arm
288 };