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
21static volatile int opened, tmr_running;
22static volatile time_t tmr_offs, tmr_ctr;
23static volatile unsigned long ticks_offs;
24static volatile int curr_tempo, curr_timebase;
25static volatile unsigned long curr_ticks;
26static volatile unsigned long next_event_time;
27static unsigned long prev_event_time;
28
29static void     poll_def_tmr(unsigned long dummy);
30static DEFINE_SPINLOCK(lock);
31static DEFINE_TIMER(def_tmr, poll_def_tmr, 0, 0);
32
33static unsigned long
34tmr2ticks(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
50static void
51poll_def_tmr(unsigned long dummy)
52{
53	if (!opened)
54		return;
55	def_tmr.expires = (1) + jiffies;
56	add_timer(&def_tmr);
57
58	if (!tmr_running)
59		return;
60
61	spin_lock(&lock);
62	tmr_ctr++;
63	curr_ticks = ticks_offs + tmr2ticks(tmr_ctr);
64
65	if (curr_ticks >= next_event_time) {
66		next_event_time = (unsigned long) -1;
67		sequencer_timer(0);
68	}
69
70	spin_unlock(&lock);
71}
72
73static void
74tmr_reset(void)
75{
76	unsigned long   flags;
77
78	spin_lock_irqsave(&lock,flags);
79	tmr_offs = 0;
80	ticks_offs = 0;
81	tmr_ctr = 0;
82	next_event_time = (unsigned long) -1;
83	prev_event_time = 0;
84	curr_ticks = 0;
85	spin_unlock_irqrestore(&lock,flags);
86}
87
88static int
89def_tmr_open(int dev, int mode)
90{
91	if (opened)
92		return -EBUSY;
93
94	tmr_reset();
95	curr_tempo = 60;
96	curr_timebase = 100;
97	opened = 1;
98	{
99		def_tmr.expires = (1) + jiffies;
100		add_timer(&def_tmr);
101	}
102
103	return 0;
104}
105
106static void
107def_tmr_close(int dev)
108{
109	opened = tmr_running = 0;
110	del_timer(&def_tmr);
111}
112
113static int
114def_tmr_event(int dev, unsigned char *event)
115{
116	unsigned char   cmd = event[1];
117	unsigned long   parm = *(int *) &event[4];
118
119	switch (cmd)
120	  {
121	  case TMR_WAIT_REL:
122		  parm += prev_event_time;
123	  case TMR_WAIT_ABS:
124		  if (parm > 0)
125		    {
126			    long            time;
127
128			    if (parm <= curr_ticks)	/* It's the time */
129				    return TIMER_NOT_ARMED;
130
131			    time = parm;
132			    next_event_time = prev_event_time = time;
133
134			    return TIMER_ARMED;
135		    }
136		  break;
137
138	  case TMR_START:
139		  tmr_reset();
140		  tmr_running = 1;
141		  break;
142
143	  case TMR_STOP:
144		  tmr_running = 0;
145		  break;
146
147	  case TMR_CONTINUE:
148		  tmr_running = 1;
149		  break;
150
151	  case TMR_TEMPO:
152		  if (parm)
153		    {
154			    if (parm < 8)
155				    parm = 8;
156			    if (parm > 360)
157				    parm = 360;
158			    tmr_offs = tmr_ctr;
159			    ticks_offs += tmr2ticks(tmr_ctr);
160			    tmr_ctr = 0;
161			    curr_tempo = parm;
162		    }
163		  break;
164
165	  case TMR_ECHO:
166		  seq_copy_to_input(event, 8);
167		  break;
168
169	  default:;
170	  }
171
172	return TIMER_NOT_ARMED;
173}
174
175static unsigned long
176def_tmr_get_time(int dev)
177{
178	if (!opened)
179		return 0;
180
181	return curr_ticks;
182}
183
184/* same as sound_timer.c:timer_ioctl!? */
185static int def_tmr_ioctl(int dev, unsigned int cmd, void __user *arg)
186{
187	int __user *p = arg;
188	int val;
189
190	switch (cmd) {
191	case SNDCTL_TMR_SOURCE:
192		return __put_user(TMR_INTERNAL, p);
193
194	case SNDCTL_TMR_START:
195		tmr_reset();
196		tmr_running = 1;
197		return 0;
198
199	case SNDCTL_TMR_STOP:
200		tmr_running = 0;
201		return 0;
202
203	case SNDCTL_TMR_CONTINUE:
204		tmr_running = 1;
205		return 0;
206
207	case SNDCTL_TMR_TIMEBASE:
208		if (__get_user(val, p))
209			return -EFAULT;
210		if (val) {
211			if (val < 1)
212				val = 1;
213			if (val > 1000)
214				val = 1000;
215			curr_timebase = val;
216		}
217		return __put_user(curr_timebase, p);
218
219	case SNDCTL_TMR_TEMPO:
220		if (__get_user(val, p))
221			return -EFAULT;
222		if (val) {
223			if (val < 8)
224				val = 8;
225			if (val > 250)
226				val = 250;
227			tmr_offs = tmr_ctr;
228			ticks_offs += tmr2ticks(tmr_ctr);
229			tmr_ctr = 0;
230			curr_tempo = val;
231			reprogram_timer();
232		}
233		return __put_user(curr_tempo, p);
234
235	case SNDCTL_SEQ_CTRLRATE:
236		if (__get_user(val, p))
237			return -EFAULT;
238		if (val != 0)	/* Can't change */
239			return -EINVAL;
240		val = ((curr_tempo * curr_timebase) + 30) / 60;
241		return __put_user(val, p);
242
243	case SNDCTL_SEQ_GETTIME:
244		return __put_user(curr_ticks, p);
245
246	case SNDCTL_TMR_METRONOME:
247		/* NOP */
248		break;
249
250	default:;
251	}
252	return -EINVAL;
253}
254
255static void
256def_tmr_arm(int dev, long time)
257{
258	if (time < 0)
259		time = curr_ticks + 1;
260	else if (time <= curr_ticks)	/* It's the time */
261		return;
262
263	next_event_time = prev_event_time = time;
264
265	return;
266}
267
268struct sound_timer_operations default_sound_timer =
269{
270	.owner		= THIS_MODULE,
271	.info		= {"System clock", 0},
272	.priority	= 0,	/* Priority */
273	.devlink	= 0,	/* Local device link */
274	.open		= def_tmr_open,
275	.close		= def_tmr_close,
276	.event		= def_tmr_event,
277	.get_time	= def_tmr_get_time,
278	.ioctl		= def_tmr_ioctl,
279	.arm_timer	= def_tmr_arm
280};
281