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	 8b169fa2c9
			
		
	
	
		8b169fa2c9
		
	
	
	
	
		
			
			EXPORT_SYMBOL's belong to the actual code. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			118 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			118 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * linux/arch/m68k/amiga/amisound.c
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|  *
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|  * amiga sound driver for Linux/m68k
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|  *
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file COPYING in the main directory of this archive
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|  * for more details.
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|  */
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| 
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| #include <linux/jiffies.h>
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| #include <linux/timer.h>
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| #include <linux/init.h>
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| #include <linux/string.h>
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| #include <linux/module.h>
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| 
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| #include <asm/system.h>
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| #include <asm/amigahw.h>
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| 
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| static unsigned short *snd_data;
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| static const signed char sine_data[] = {
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| 	0,  39,  75,  103,  121,  127,  121,  103,  75,  39,
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| 	0, -39, -75, -103, -121, -127, -121, -103, -75, -39
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| };
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| #define DATA_SIZE	ARRAY_SIZE(sine_data)
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| 
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| #define custom amiga_custom
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| 
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|     /*
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|      * The minimum period for audio may be modified by the frame buffer
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|      * device since it depends on htotal (for OCS/ECS/AGA)
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|      */
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| 
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| volatile unsigned short amiga_audio_min_period = 124; /* Default for pre-OCS */
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| EXPORT_SYMBOL(amiga_audio_min_period);
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| 
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| #define MAX_PERIOD	(65535)
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| 
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| 
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|     /*
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|      *	Current period (set by dmasound.c)
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|      */
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| 
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| unsigned short amiga_audio_period = MAX_PERIOD;
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| EXPORT_SYMBOL(amiga_audio_period);
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| 
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| static unsigned long clock_constant;
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| 
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| void __init amiga_init_sound(void)
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| {
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| 	static struct resource beep_res = { .name = "Beep" };
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| 
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| 	snd_data = amiga_chip_alloc_res(sizeof(sine_data), &beep_res);
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| 	if (!snd_data) {
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| 		printk (KERN_CRIT "amiga init_sound: failed to allocate chipmem\n");
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| 		return;
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| 	}
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| 	memcpy (snd_data, sine_data, sizeof(sine_data));
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| 
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| 	/* setup divisor */
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| 	clock_constant = (amiga_colorclock+DATA_SIZE/2)/DATA_SIZE;
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| 
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| 	/* without amifb, turn video off and enable high quality sound */
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| #ifndef CONFIG_FB_AMIGA
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| 	amifb_video_off();
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| #endif
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| }
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| 
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| static void nosound( unsigned long ignored );
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| static DEFINE_TIMER(sound_timer, nosound, 0, 0);
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| 
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| void amiga_mksound( unsigned int hz, unsigned int ticks )
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| {
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| 	unsigned long flags;
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| 
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| 	if (!snd_data)
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| 		return;
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| 
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| 	local_irq_save(flags);
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| 	del_timer( &sound_timer );
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| 
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| 	if (hz > 20 && hz < 32767) {
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| 		unsigned long period = (clock_constant / hz);
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| 
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| 		if (period < amiga_audio_min_period)
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| 			period = amiga_audio_min_period;
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| 		if (period > MAX_PERIOD)
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| 			period = MAX_PERIOD;
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| 
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| 		/* setup pointer to data, period, length and volume */
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| 		custom.aud[2].audlc = snd_data;
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| 		custom.aud[2].audlen = sizeof(sine_data)/2;
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| 		custom.aud[2].audper = (unsigned short)period;
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| 		custom.aud[2].audvol = 32; /* 50% of maxvol */
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| 
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| 		if (ticks) {
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| 			sound_timer.expires = jiffies + ticks;
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| 			add_timer( &sound_timer );
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| 		}
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| 
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| 		/* turn on DMA for audio channel 2 */
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| 		custom.dmacon = DMAF_SETCLR | DMAF_AUD2;
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| 
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| 	} else
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| 		nosound( 0 );
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| 
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| 	local_irq_restore(flags);
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| }
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| 
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| 
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| static void nosound( unsigned long ignored )
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| {
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| 	/* turn off DMA for audio channel 2 */
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| 	custom.dmacon = DMAF_AUD2;
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| 	/* restore period to previous value after beeping */
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| 	custom.aud[2].audper = amiga_audio_period;
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| }
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