blob: 61e5c54625aeee7dd2a3a206e38051c6430ea0bd [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/m68k/amiga/amisound.c
3 *
4 * amiga sound driver for Linux/m68k
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive
8 * for more details.
9 */
10
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/jiffies.h>
12#include <linux/timer.h>
13#include <linux/init.h>
14#include <linux/string.h>
Adrian Bunk8b169fa2008-02-04 22:30:25 -080015#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016
17#include <asm/system.h>
18#include <asm/amigahw.h>
19
20static unsigned short *snd_data;
21static const signed char sine_data[] = {
22 0, 39, 75, 103, 121, 127, 121, 103, 75, 39,
23 0, -39, -75, -103, -121, -127, -121, -103, -75, -39
24};
Alejandro Martinez Ruizb9e5e112008-02-04 22:30:17 -080025#define DATA_SIZE ARRAY_SIZE(sine_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -070026
Al Virob4290a22006-01-12 01:06:12 -080027#define custom amiga_custom
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 /*
30 * The minimum period for audio may be modified by the frame buffer
31 * device since it depends on htotal (for OCS/ECS/AGA)
32 */
33
34volatile unsigned short amiga_audio_min_period = 124; /* Default for pre-OCS */
Adrian Bunk8b169fa2008-02-04 22:30:25 -080035EXPORT_SYMBOL(amiga_audio_min_period);
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
37#define MAX_PERIOD (65535)
38
39
40 /*
41 * Current period (set by dmasound.c)
42 */
43
44unsigned short amiga_audio_period = MAX_PERIOD;
Adrian Bunk8b169fa2008-02-04 22:30:25 -080045EXPORT_SYMBOL(amiga_audio_period);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47static unsigned long clock_constant;
48
49void __init amiga_init_sound(void)
50{
51 static struct resource beep_res = { .name = "Beep" };
52
53 snd_data = amiga_chip_alloc_res(sizeof(sine_data), &beep_res);
54 if (!snd_data) {
55 printk (KERN_CRIT "amiga init_sound: failed to allocate chipmem\n");
56 return;
57 }
58 memcpy (snd_data, sine_data, sizeof(sine_data));
59
60 /* setup divisor */
61 clock_constant = (amiga_colorclock+DATA_SIZE/2)/DATA_SIZE;
62
63 /* without amifb, turn video off and enable high quality sound */
64#ifndef CONFIG_FB_AMIGA
65 amifb_video_off();
66#endif
67}
68
69static void nosound( unsigned long ignored );
Ingo Molnar8d06afa2005-09-09 13:10:40 -070070static DEFINE_TIMER(sound_timer, nosound, 0, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070071
72void amiga_mksound( unsigned int hz, unsigned int ticks )
73{
74 unsigned long flags;
75
76 if (!snd_data)
77 return;
78
79 local_irq_save(flags);
80 del_timer( &sound_timer );
81
82 if (hz > 20 && hz < 32767) {
83 unsigned long period = (clock_constant / hz);
84
85 if (period < amiga_audio_min_period)
86 period = amiga_audio_min_period;
87 if (period > MAX_PERIOD)
88 period = MAX_PERIOD;
89
90 /* setup pointer to data, period, length and volume */
91 custom.aud[2].audlc = snd_data;
92 custom.aud[2].audlen = sizeof(sine_data)/2;
93 custom.aud[2].audper = (unsigned short)period;
94 custom.aud[2].audvol = 32; /* 50% of maxvol */
95
96 if (ticks) {
97 sound_timer.expires = jiffies + ticks;
98 add_timer( &sound_timer );
99 }
100
101 /* turn on DMA for audio channel 2 */
102 custom.dmacon = DMAF_SETCLR | DMAF_AUD2;
103
104 } else
105 nosound( 0 );
106
107 local_irq_restore(flags);
108}
109
110
111static void nosound( unsigned long ignored )
112{
113 /* turn off DMA for audio channel 2 */
114 custom.dmacon = DMAF_AUD2;
115 /* restore period to previous value after beeping */
116 custom.aud[2].audper = amiga_audio_period;
117}