GBA Audio: Support 16-bit writes to FIFO audio

src/gba/gba-audio.c

@@ -453,6 +453,30 @@ void GBAAudioWriteFIFO(struct GBAAudio* audio, int address, uint32_t value) {
 	}
 }
 
+void GBAAudioWriteFIFO16(struct GBAAudio* audio, int address, uint16_t value) {
+	struct CircleBuffer* fifo;
+	switch (address) {
+	case REG_FIFO_A_LO:
+	case REG_FIFO_A_HI:
+		fifo = &audio->chA.fifo;
+		break;
+	case REG_FIFO_B_LO:
+	case REG_FIFO_B_HI:
+		fifo = &audio->chB.fifo;
+		break;
+	default:
+		GBALog(audio->p, GBA_LOG_ERROR, "Bad FIFO write to address 0x%03x", address);
+		return;
+	}
+	int i;
+	for (i = 0; i < 2; ++i) {
+		while (!CircleBufferWrite8(fifo, value >> (8 * i))) {
+			int8_t dummy;
+			CircleBufferRead8(fifo, &dummy);
+		}
+	}
+}
+
 void GBAAudioSampleFIFO(struct GBAAudio* audio, int fifoId, int32_t cycles) {
 	struct GBAAudioFIFO* channel;
 	if (fifoId == 0) {

src/gba/gba-audio.h

@@ -252,6 +252,7 @@ void GBAAudioWriteSOUNDCNT_X(struct GBAAudio* audio, uint16_t value);
 void GBAAudioWriteSOUNDBIAS(struct GBAAudio* audio, uint16_t value);
 
 void GBAAudioWriteWaveRAM(struct GBAAudio* audio, int address, uint32_t value);
+void GBAAudioWriteFIFO16(struct GBAAudio* audio, int address, uint16_t value);
 void GBAAudioWriteFIFO(struct GBAAudio* audio, int address, uint32_t value);
 void GBAAudioSampleFIFO(struct GBAAudio* audio, int fifoId, int32_t cycles);
 

src/gba/gba-io.c

@@ -356,18 +356,21 @@ void GBAIOWrite(struct GBA* gba, uint32_t address, uint16_t value) {
 		case REG_WAVE_RAM1_LO:
 		case REG_WAVE_RAM2_LO:
 		case REG_WAVE_RAM3_LO:
-		case REG_FIFO_A_LO:
-		case REG_FIFO_B_LO:
 			GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
 			break;
 
 		case REG_WAVE_RAM0_HI:
 		case REG_WAVE_RAM1_HI:
 		case REG_WAVE_RAM2_HI:
 		case REG_WAVE_RAM3_HI:
+			GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
+			break;
+
+		case REG_FIFO_A_LO:
+		case REG_FIFO_B_LO:
 		case REG_FIFO_A_HI:
 		case REG_FIFO_B_HI:
-			GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
+			GBAAudioWriteFIFO16(&gba->audio, address, value);
 			break;
 
 		// DMA