perf: Correctly align perf event tracing buffer
[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                 def_tmr.expires = (1) + jiffies;
105                 add_timer(&def_tmr);
106         };
107
108         return 0;
109 }
110
111 static void
112 def_tmr_close(int dev)
113 {
114         opened = tmr_running = 0;
115         del_timer(&def_tmr);
116 }
117
118 static int
119 def_tmr_event(int dev, unsigned char *event)
120 {
121         unsigned char   cmd = event[1];
122         unsigned long   parm = *(int *) &event[4];
123
124         switch (cmd)
125           {
126           case TMR_WAIT_REL:
127                   parm += prev_event_time;
128           case TMR_WAIT_ABS:
129                   if (parm > 0)
130                     {
131                             long            time;
132
133                             if (parm <= curr_ticks)     /* It's the time */
134                                     return TIMER_NOT_ARMED;
135
136                             time = parm;
137                             next_event_time = prev_event_time = time;
138
139                             return TIMER_ARMED;
140                     }
141                   break;
142
143           case TMR_START:
144                   tmr_reset();
145                   tmr_running = 1;
146                   break;
147
148           case TMR_STOP:
149                   tmr_running = 0;
150                   break;
151
152           case TMR_CONTINUE:
153                   tmr_running = 1;
154                   break;
155
156           case TMR_TEMPO:
157                   if (parm)
158                     {
159                             if (parm < 8)
160                                     parm = 8;
161                             if (parm > 360)
162                                     parm = 360;
163                             tmr_offs = tmr_ctr;
164                             ticks_offs += tmr2ticks(tmr_ctr);
165                             tmr_ctr = 0;
166                             curr_tempo = parm;
167                     }
168                   break;
169
170           case TMR_ECHO:
171                   seq_copy_to_input(event, 8);
172                   break;
173
174           default:;
175           }
176
177         return TIMER_NOT_ARMED;
178 }
179
180 static unsigned long
181 def_tmr_get_time(int dev)
182 {
183         if (!opened)
184                 return 0;
185
186         return curr_ticks;
187 }
188
189 /* same as sound_timer.c:timer_ioctl!? */
190 static int def_tmr_ioctl(int dev, unsigned int cmd, void __user *arg)
191 {
192         int __user *p = arg;
193         int val;
194
195         switch (cmd) {
196         case SNDCTL_TMR_SOURCE:
197                 return __put_user(TMR_INTERNAL, p);
198
199         case SNDCTL_TMR_START:
200                 tmr_reset();
201                 tmr_running = 1;
202                 return 0;
203
204         case SNDCTL_TMR_STOP:
205                 tmr_running = 0;
206                 return 0;
207
208         case SNDCTL_TMR_CONTINUE:
209                 tmr_running = 1;
210                 return 0;
211
212         case SNDCTL_TMR_TIMEBASE:
213                 if (__get_user(val, p))
214                         return -EFAULT;
215                 if (val) {
216                         if (val < 1)
217                                 val = 1;
218                         if (val > 1000)
219                                 val = 1000;
220                         curr_timebase = val;
221                 }
222                 return __put_user(curr_timebase, p);
223
224         case SNDCTL_TMR_TEMPO:
225                 if (__get_user(val, p))
226                         return -EFAULT;
227                 if (val) {
228                         if (val < 8)
229                                 val = 8;
230                         if (val > 250)
231                                 val = 250;
232                         tmr_offs = tmr_ctr;
233                         ticks_offs += tmr2ticks(tmr_ctr);
234                         tmr_ctr = 0;
235                         curr_tempo = val;
236                         reprogram_timer();
237                 }
238                 return __put_user(curr_tempo, p);
239
240         case SNDCTL_SEQ_CTRLRATE:
241                 if (__get_user(val, p))
242                         return -EFAULT;
243                 if (val != 0)   /* Can't change */
244                         return -EINVAL;
245                 val = ((curr_tempo * curr_timebase) + 30) / 60;
246                 return __put_user(val, p);
247                 
248         case SNDCTL_SEQ_GETTIME:
249                 return __put_user(curr_ticks, p);
250                 
251         case SNDCTL_TMR_METRONOME:
252                 /* NOP */
253                 break;
254                 
255         default:;
256         }
257         return -EINVAL;
258 }
259
260 static void
261 def_tmr_arm(int dev, long time)
262 {
263         if (time < 0)
264                 time = curr_ticks + 1;
265         else if (time <= curr_ticks)    /* It's the time */
266                 return;
267
268         next_event_time = prev_event_time = time;
269
270         return;
271 }
272
273 struct sound_timer_operations default_sound_timer =
274 {
275         .owner          = THIS_MODULE,
276         .info           = {"System clock", 0},
277         .priority       = 0,    /* Priority */
278         .devlink        = 0,    /* Local device link */
279         .open           = def_tmr_open,
280         .close          = def_tmr_close,
281         .event          = def_tmr_event,
282         .get_time       = def_tmr_get_time,
283         .ioctl          = def_tmr_ioctl,
284         .arm_timer      = def_tmr_arm
285 };