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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/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);

}