1 files changed, 116 insertions, 0 deletions
diff --git a/arch/m68k/amiga/amisound.c b/arch/m68k/amiga/amisound.c
new file mode 100644
index 000000000..442bdeee6
--- /dev/null
+++ b/arch/m68k/amiga/amisound.c
@@ -0,0 +1,116 @@
+/*
+ * linux/arch/m68k/amiga/amisound.c
+ *
+ * amiga sound driver for Linux/m68k
+ *
+ * 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/jiffies.h>
+#include <linux/timer.h>
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/module.h>
+
+#include <asm/amigahw.h>
+
+static unsigned short *snd_data;
+static const signed char sine_data[] = {
+	0,  39,  75,  103,  121,  127,  121,  103,  75,  39,
+	0, -39, -75, -103, -121, -127, -121, -103, -75, -39
+};
+#define DATA_SIZE	ARRAY_SIZE(sine_data)
+
+#define custom amiga_custom
+
+    /*
+     * The minimum period for audio may be modified by the frame buffer
+     * device since it depends on htotal (for OCS/ECS/AGA)
+     */
+
+volatile unsigned short amiga_audio_min_period = 124; /* Default for pre-OCS */
+EXPORT_SYMBOL(amiga_audio_min_period);
+
+#define MAX_PERIOD	(65535)
+
+
+    /*
+     *	Current period (set by dmasound.c)
+     */
+
+unsigned short amiga_audio_period = MAX_PERIOD;
+EXPORT_SYMBOL(amiga_audio_period);
+
+static unsigned long clock_constant;
+
+void __init amiga_init_sound(void)
+{
+	static struct resource beep_res = { .name = "Beep" };
+
+	snd_data = amiga_chip_alloc_res(sizeof(sine_data), &beep_res);
+	if (!snd_data) {
+		pr_crit("amiga init_sound: failed to allocate chipmem\n");
+		return;
+	}
+	memcpy (snd_data, sine_data, sizeof(sine_data));
+
+	/* setup divisor */
+	clock_constant = (amiga_colorclock+DATA_SIZE/2)/DATA_SIZE;
+
+	/* without amifb, turn video off and enable high quality sound */
+#ifndef CONFIG_FB_AMIGA
+	amifb_video_off();
+#endif
+}
+
+static void nosound(struct timer_list *unused);
+static DEFINE_TIMER(sound_timer, nosound);
+
+void amiga_mksound( unsigned int hz, unsigned int ticks )
+{
+	unsigned long flags;
+
+	if (!snd_data)
+		return;
+
+	local_irq_save(flags);
+	del_timer( &sound_timer );
+
+	if (hz > 20 && hz < 32767) {
+		unsigned long period = (clock_constant / hz);
+
+		if (period < amiga_audio_min_period)
+			period = amiga_audio_min_period;
+		if (period > MAX_PERIOD)
+			period = MAX_PERIOD;
+
+		/* setup pointer to data, period, length and volume */
+		custom.aud[2].audlc = snd_data;
+		custom.aud[2].audlen = sizeof(sine_data)/2;
+		custom.aud[2].audper = (unsigned short)period;
+		custom.aud[2].audvol = 32; /* 50% of maxvol */
+
+		if (ticks) {
+			sound_timer.expires = jiffies + ticks;
+			add_timer( &sound_timer );
+		}
+
+		/* turn on DMA for audio channel 2 */
+		custom.dmacon = DMAF_SETCLR | DMAF_AUD2;
+
+	} else
+		nosound( 0 );
+
+	local_irq_restore(flags);
+}
+
+
+static void nosound(struct timer_list *unused)
+{
+	/* turn off DMA for audio channel 2 */
+	custom.dmacon = DMAF_AUD2;
+	/* restore period to previous value after beeping */
+	custom.aud[2].audper = amiga_audio_period;
+}