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 def_tmr.expires = (1) + jiffies;
105 add_timer(&def_tmr);
106 }
107
108 return 0;
109 }
110
111 static void
def_tmr_close(int dev)112 def_tmr_close(int dev)
113 {
114 opened = tmr_running = 0;
115 del_timer(&def_tmr);
116 }
117
118 static int
def_tmr_event(int dev,unsigned char * event)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
def_tmr_get_time(int dev)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!? */
def_tmr_ioctl(int dev,unsigned int cmd,void __user * arg)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
def_tmr_arm(int dev,long time)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 };
286