File: /usr/src/linux/drivers/sound/emu10k1/timer.c
1
2 /*
3 **********************************************************************
4 * timer.c
5 * Copyright (C) 1999, 2000 Creative Labs, inc.
6 *
7 **********************************************************************
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public
20 * License along with this program; if not, write to the Free
21 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
22 * USA.
23 *
24 **********************************************************************
25 */
26
27 /* 3/6/2000 Improved support for different timer delays Rui Sousa */
28
29 /* 4/3/2000 Implemented timer list using list.h Rui Sousa */
30
31 #include "hwaccess.h"
32 #include "8010.h"
33 #include "irqmgr.h"
34 #include "timer.h"
35
36 /* Try to schedule only once per fragment */
37
38 void emu10k1_timer_irqhandler(struct emu10k1_card *card)
39 {
40 struct emu_timer *t;
41 struct list_head *entry;
42
43 spin_lock(&card->timer_lock);
44
45 list_for_each(entry, &card->timers) {
46 t = list_entry(entry, struct emu_timer, list);
47
48 if (t->state & TIMER_STATE_ACTIVE) {
49 t->count++;
50 if (t->count == t->count_max) {
51 t->count = 0;
52 tasklet_hi_schedule(&t->tasklet);
53 }
54 }
55 }
56
57 spin_unlock(&card->timer_lock);
58
59 return;
60 }
61
62 void emu10k1_timer_install(struct emu10k1_card *card, struct emu_timer *timer, u32 delay)
63 {
64 struct emu_timer *t;
65 struct list_head *entry;
66 unsigned long flags;
67
68 if (delay < 5)
69 delay = 5;
70
71 timer->delay = delay;
72 timer->state = TIMER_STATE_INSTALLED;
73
74 spin_lock_irqsave(&card->timer_lock, flags);
75
76 timer->count_max = timer->delay / (card->timer_delay < 1024 ? card->timer_delay : 1024);
77 timer->count = timer->count_max - 1;
78
79 list_add(&timer->list, &card->timers);
80
81 if (card->timer_delay > delay) {
82 if (card->timer_delay == TIMER_STOPPED)
83 emu10k1_irq_enable(card, INTE_INTERVALTIMERENB);
84
85 card->timer_delay = delay;
86 delay = (delay < 1024 ? delay : 1024);
87
88 emu10k1_writefn0(card, TIMER_RATE, delay);
89
90 list_for_each(entry, &card->timers) {
91 t = list_entry(entry, struct emu_timer, list);
92
93 t->count_max = t->delay / delay;
94 /* don't want to think much, just force scheduling
95 on the next interrupt */
96 t->count = t->count_max - 1;
97 }
98
99 DPD(2, "timer rate --> %u\n", delay);
100 }
101
102 spin_unlock_irqrestore(&card->timer_lock, flags);
103
104 return;
105 }
106
107 void emu10k1_timer_uninstall(struct emu10k1_card *card, struct emu_timer *timer)
108 {
109 struct emu_timer *t;
110 struct list_head *entry;
111 u32 delay = TIMER_STOPPED;
112 unsigned long flags;
113
114 if (timer->state == TIMER_STATE_UNINSTALLED)
115 return;
116
117 spin_lock_irqsave(&card->timer_lock, flags);
118
119 list_del(&timer->list);
120
121 list_for_each(entry, &card->timers) {
122 t = list_entry(entry, struct emu_timer, list);
123
124 if (t->delay < delay)
125 delay = t->delay;
126 }
127
128 if (card->timer_delay != delay) {
129 card->timer_delay = delay;
130
131 if (delay == TIMER_STOPPED)
132 emu10k1_irq_disable(card, INTE_INTERVALTIMERENB);
133 else {
134 delay = (delay < 1024 ? delay : 1024);
135
136 emu10k1_writefn0(card, TIMER_RATE, delay);
137
138 list_for_each(entry, &card->timers) {
139 t = list_entry(entry, struct emu_timer, list);
140
141 t->count_max = t->delay / delay;
142 t->count = t->count_max - 1;
143 }
144 }
145
146 DPD(2, "timer rate --> %u\n", delay);
147 }
148
149 spin_unlock_irqrestore(&card->timer_lock, flags);
150
151 timer->state = TIMER_STATE_UNINSTALLED;
152
153 return;
154 }
155
156 void emu10k1_timer_enable(struct emu10k1_card *card, struct emu_timer *timer)
157 {
158 unsigned long flags;
159
160 spin_lock_irqsave(&card->timer_lock, flags);
161 timer->state |= TIMER_STATE_ACTIVE;
162 spin_unlock_irqrestore(&card->timer_lock, flags);
163
164 return;
165 }
166
167 void emu10k1_timer_disable(struct emu10k1_card *card, struct emu_timer *timer)
168 {
169 unsigned long flags;
170
171 spin_lock_irqsave(&card->timer_lock, flags);
172 timer->state &= ~TIMER_STATE_ACTIVE;
173 spin_unlock_irqrestore(&card->timer_lock, flags);
174
175 return;
176 }
177