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
tmr2ticks(int tmr_value)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
poll_def_tmr(unsigned long dummy)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
tmr_reset(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
def_tmr_open(int dev,int mode)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
def_tmr_close(int dev)115 def_tmr_close(int dev)
116 {
117 opened = tmr_running = 0;
118 del_timer(&def_tmr);
119 }
120
121 static int
def_tmr_event(int dev,unsigned char * event)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
def_tmr_get_time(int dev)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!? */
def_tmr_ioctl(int dev,unsigned int cmd,void __user * arg)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
def_tmr_arm(int dev,long time)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 };
289