1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * linux/arch/m68k/amiga/amisound.c
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * amiga sound driver for Linux/m68k
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * This file is subject to the terms and conditions of the GNU General Public
7*4882a593Smuzhiyun * License. See the file COPYING in the main directory of this archive
8*4882a593Smuzhiyun * for more details.
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include <linux/jiffies.h>
12*4882a593Smuzhiyun #include <linux/timer.h>
13*4882a593Smuzhiyun #include <linux/init.h>
14*4882a593Smuzhiyun #include <linux/string.h>
15*4882a593Smuzhiyun #include <linux/module.h>
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun #include <asm/amigahw.h>
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun static unsigned short *snd_data;
20*4882a593Smuzhiyun static const signed char sine_data[] = {
21*4882a593Smuzhiyun 0, 39, 75, 103, 121, 127, 121, 103, 75, 39,
22*4882a593Smuzhiyun 0, -39, -75, -103, -121, -127, -121, -103, -75, -39
23*4882a593Smuzhiyun };
24*4882a593Smuzhiyun #define DATA_SIZE ARRAY_SIZE(sine_data)
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun #define custom amiga_custom
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun /*
29*4882a593Smuzhiyun * The minimum period for audio may be modified by the frame buffer
30*4882a593Smuzhiyun * device since it depends on htotal (for OCS/ECS/AGA)
31*4882a593Smuzhiyun */
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun volatile unsigned short amiga_audio_min_period = 124; /* Default for pre-OCS */
34*4882a593Smuzhiyun EXPORT_SYMBOL(amiga_audio_min_period);
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun #define MAX_PERIOD (65535)
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun /*
40*4882a593Smuzhiyun * Current period (set by dmasound.c)
41*4882a593Smuzhiyun */
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun unsigned short amiga_audio_period = MAX_PERIOD;
44*4882a593Smuzhiyun EXPORT_SYMBOL(amiga_audio_period);
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun static unsigned long clock_constant;
47*4882a593Smuzhiyun
amiga_init_sound(void)48*4882a593Smuzhiyun void __init amiga_init_sound(void)
49*4882a593Smuzhiyun {
50*4882a593Smuzhiyun static struct resource beep_res = { .name = "Beep" };
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun snd_data = amiga_chip_alloc_res(sizeof(sine_data), &beep_res);
53*4882a593Smuzhiyun if (!snd_data) {
54*4882a593Smuzhiyun pr_crit("amiga init_sound: failed to allocate chipmem\n");
55*4882a593Smuzhiyun return;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun memcpy (snd_data, sine_data, sizeof(sine_data));
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun /* setup divisor */
60*4882a593Smuzhiyun clock_constant = (amiga_colorclock+DATA_SIZE/2)/DATA_SIZE;
61*4882a593Smuzhiyun
62*4882a593Smuzhiyun /* without amifb, turn video off and enable high quality sound */
63*4882a593Smuzhiyun #ifndef CONFIG_FB_AMIGA
64*4882a593Smuzhiyun amifb_video_off();
65*4882a593Smuzhiyun #endif
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun static void nosound(struct timer_list *unused);
69*4882a593Smuzhiyun static DEFINE_TIMER(sound_timer, nosound);
70*4882a593Smuzhiyun
amiga_mksound(unsigned int hz,unsigned int ticks)71*4882a593Smuzhiyun void amiga_mksound( unsigned int hz, unsigned int ticks )
72*4882a593Smuzhiyun {
73*4882a593Smuzhiyun unsigned long flags;
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun if (!snd_data)
76*4882a593Smuzhiyun return;
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun local_irq_save(flags);
79*4882a593Smuzhiyun del_timer( &sound_timer );
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun if (hz > 20 && hz < 32767) {
82*4882a593Smuzhiyun unsigned long period = (clock_constant / hz);
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun if (period < amiga_audio_min_period)
85*4882a593Smuzhiyun period = amiga_audio_min_period;
86*4882a593Smuzhiyun if (period > MAX_PERIOD)
87*4882a593Smuzhiyun period = MAX_PERIOD;
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun /* setup pointer to data, period, length and volume */
90*4882a593Smuzhiyun custom.aud[2].audlc = snd_data;
91*4882a593Smuzhiyun custom.aud[2].audlen = sizeof(sine_data)/2;
92*4882a593Smuzhiyun custom.aud[2].audper = (unsigned short)period;
93*4882a593Smuzhiyun custom.aud[2].audvol = 32; /* 50% of maxvol */
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun if (ticks) {
96*4882a593Smuzhiyun sound_timer.expires = jiffies + ticks;
97*4882a593Smuzhiyun add_timer( &sound_timer );
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun /* turn on DMA for audio channel 2 */
101*4882a593Smuzhiyun custom.dmacon = DMAF_SETCLR | DMAF_AUD2;
102*4882a593Smuzhiyun
103*4882a593Smuzhiyun } else
104*4882a593Smuzhiyun nosound( 0 );
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun local_irq_restore(flags);
107*4882a593Smuzhiyun }
108*4882a593Smuzhiyun
109*4882a593Smuzhiyun
nosound(struct timer_list * unused)110*4882a593Smuzhiyun static void nosound(struct timer_list *unused)
111*4882a593Smuzhiyun {
112*4882a593Smuzhiyun /* turn off DMA for audio channel 2 */
113*4882a593Smuzhiyun custom.dmacon = DMAF_AUD2;
114*4882a593Smuzhiyun /* restore period to previous value after beeping */
115*4882a593Smuzhiyun custom.aud[2].audper = amiga_audio_period;
116*4882a593Smuzhiyun }
117