1 /*
2 * Copyright (c) by Lee Revell <rlrevell@joe-job.com>
3 * Clemens Ladisch <clemens@ladisch.de>
4 * Routines for control of EMU10K1 chips
5 *
6 * BUGS:
7 * --
8 *
9 * TODO:
10 * --
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 *
26 */
27
28 #include <linux/time.h>
29 #include <sound/core.h>
30 #include <sound/emu10k1.h>
31
snd_emu10k1_timer_start(struct snd_timer * timer)32 static int snd_emu10k1_timer_start(struct snd_timer *timer)
33 {
34 struct snd_emu10k1 *emu;
35 unsigned long flags;
36 unsigned int delay;
37
38 emu = snd_timer_chip(timer);
39 delay = timer->sticks - 1;
40 if (delay < 5 ) /* minimum time is 5 ticks */
41 delay = 5;
42 spin_lock_irqsave(&emu->reg_lock, flags);
43 snd_emu10k1_intr_enable(emu, INTE_INTERVALTIMERENB);
44 outw(delay & TIMER_RATE_MASK, emu->port + TIMER);
45 spin_unlock_irqrestore(&emu->reg_lock, flags);
46 return 0;
47 }
48
snd_emu10k1_timer_stop(struct snd_timer * timer)49 static int snd_emu10k1_timer_stop(struct snd_timer *timer)
50 {
51 struct snd_emu10k1 *emu;
52 unsigned long flags;
53
54 emu = snd_timer_chip(timer);
55 spin_lock_irqsave(&emu->reg_lock, flags);
56 snd_emu10k1_intr_disable(emu, INTE_INTERVALTIMERENB);
57 spin_unlock_irqrestore(&emu->reg_lock, flags);
58 return 0;
59 }
60
snd_emu10k1_timer_precise_resolution(struct snd_timer * timer,unsigned long * num,unsigned long * den)61 static int snd_emu10k1_timer_precise_resolution(struct snd_timer *timer,
62 unsigned long *num, unsigned long *den)
63 {
64 *num = 1;
65 *den = 48000;
66 return 0;
67 }
68
69 static struct snd_timer_hardware snd_emu10k1_timer_hw = {
70 .flags = SNDRV_TIMER_HW_AUTO,
71 .resolution = 20833, /* 1 sample @ 48KHZ = 20.833...us */
72 .ticks = 1024,
73 .start = snd_emu10k1_timer_start,
74 .stop = snd_emu10k1_timer_stop,
75 .precise_resolution = snd_emu10k1_timer_precise_resolution,
76 };
77
snd_emu10k1_timer(struct snd_emu10k1 * emu,int device)78 int snd_emu10k1_timer(struct snd_emu10k1 *emu, int device)
79 {
80 struct snd_timer *timer = NULL;
81 struct snd_timer_id tid;
82 int err;
83
84 tid.dev_class = SNDRV_TIMER_CLASS_CARD;
85 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
86 tid.card = emu->card->number;
87 tid.device = device;
88 tid.subdevice = 0;
89 if ((err = snd_timer_new(emu->card, "EMU10K1", &tid, &timer)) >= 0) {
90 strcpy(timer->name, "EMU10K1 timer");
91 timer->private_data = emu;
92 timer->hw = snd_emu10k1_timer_hw;
93 }
94 emu->timer = timer;
95 return err;
96 }
97