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/*
linux/arch/m68k/atari/atasound.c
++Geert: Moved almost all stuff to linux/drivers/sound/
The author of atari_nosound, atari_mksound and atari_microwire_cmd is
unknown.
(++roman: That's me... :-)
This file is subject to the terms and conditions of the GNU General Public
License. See the file COPYING in the main directory of this archive
for more details.
*/
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/config.h>
#include <linux/fcntl.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <asm/atarihw.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <asm/pgtable.h>
#include <asm/atariints.h>
#include <asm/bootinfo.h>
/*
* stuff from the old atasound.c
*/
static void atari_nosound (unsigned long ignored)
{
unsigned char tmp;
unsigned long flags;
/* turn off generator A in mixer control */
save_flags(flags);
cli();
sound_ym.rd_data_reg_sel = 7;
tmp = sound_ym.rd_data_reg_sel;
sound_ym.wd_data = tmp | 0x39;
restore_flags(flags);
}
void atari_microwire_cmd (int cmd)
{
tt_microwire.mask = 0x7ff;
tt_microwire.data = MW_LM1992_ADDR | cmd;
/* Busy wait for data being completely sent :-( */
while( tt_microwire.mask != 0x7ff)
;
}
#define PC_FREQ 1192180
#define PSG_FREQ 125000
void atari_mksound (unsigned int count, unsigned int ticks)
{
static struct timer_list sound_timer = { NULL, NULL, 0, 0,
atari_nosound };
/*
* Generates sound of some count for some number of clock ticks
* [count = 1193180 / frequency]
*/
unsigned long flags;
unsigned char tmp;
save_flags(flags);
cli();
if (count == 750 && ticks == HZ/8) {
/* Special case: These values are used by console.c to
* generate the console bell. They are cached here and the
* sound actually generated is somehow special: it uses the
* generator B and an envelope. No timer is needed therefore
* and the bell doesn't disturb an other ongoing sound.
*/
/* set envelope duration to 492 ms */
sound_ym.rd_data_reg_sel = 11;
sound_ym.wd_data = 0;
sound_ym.rd_data_reg_sel = 12;
sound_ym.wd_data = 15;
/* envelope form: max -> min single */
sound_ym.rd_data_reg_sel = 13;
sound_ym.wd_data = 9;
/* set generator B frequency to 2400 Hz */
sound_ym.rd_data_reg_sel = 2;
sound_ym.wd_data = 52;
sound_ym.rd_data_reg_sel = 3;
sound_ym.wd_data = 0;
/* set volume of generator B to envelope control */
sound_ym.rd_data_reg_sel = 9;
sound_ym.wd_data = 0x10;
/* enable generator B in the mixer control */
sound_ym.rd_data_reg_sel = 7;
tmp = sound_ym.rd_data_reg_sel;
sound_ym.wd_data = (tmp & ~0x02) | 0x38;
restore_flags(flags);
return;
}
del_timer( &sound_timer );
if (!count) {
atari_nosound( 0 );
}
else {
/* convert from PC counter value (base frequency 1.193 MHz)
* to PSG period value (base frequency 125 kHz).
*/
int period = (PSG_FREQ * count + PC_FREQ/2) / PC_FREQ;
if (period > 0xfff) period = 0xfff;
/* set generator A frequency to 0 */
sound_ym.rd_data_reg_sel = 0;
sound_ym.wd_data = period & 0xff;
sound_ym.rd_data_reg_sel = 1;
sound_ym.wd_data = (period >> 8) & 0xf;
/* turn on generator A in mixer control (but not noise
* generator!) */
sound_ym.rd_data_reg_sel = 7;
tmp = sound_ym.rd_data_reg_sel;
sound_ym.wd_data = (tmp & ~0x01) | 0x38;
/* set generator A level to maximum, no envelope */
sound_ym.rd_data_reg_sel = 8;
sound_ym.wd_data = 15;
if (ticks) {
sound_timer.expires = jiffies + ticks;
add_timer( &sound_timer );
}
}
restore_flags(flags);
}
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