- added way to prevent a race condition when reading the touchscreen values

- simplified CODEC init and read code
- fixed I2C register

thanks to @profi200 for the last two points

arm11/source/hw/codec.c

@@ -68,6 +68,12 @@ static u8 CODEC_RegRead(u8 reg)
 	return ret;
 }
 
+static void CODEC_RegReadBuf(u8 reg, u32 *out, u8 size)
+{
+	u32 cmd = (reg << 1) | 1;
+	CODEC_WriteRead(&cmd, 1, out, size);
+}
+
 static void CODEC_RegWrite(u8 reg, u8 val)
 {
 	SPI_XferInfo xfer;
@@ -82,54 +88,34 @@ static void CODEC_RegWrite(u8 reg, u8 val)
 	SPI_DoXfer(CODEC_SPI_DEV, &xfer, 1);
 }
 
-static void CODEC_RegReadBuf(u8 reg, u32 *out, u8 size)
-{
-	u32 cmd = (reg << 1) | 1;
-	CODEC_WriteRead(&cmd, 1, out, size);
-}
-
 static void CODEC_RegMask(u8 reg, u8 mask0, u8 mask1)
 {
 	CODEC_RegWrite(reg, (CODEC_RegRead(reg) & ~mask1) | (mask0 & mask1));
 }
 
+// elder god magic
 void CODEC_Init(void)
 {
 	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x24, 0x98);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x26, 0x00);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x25, 0x43);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x24, 0x18);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x17, 0x43);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x19, 0x69);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x1B, 0x80);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x27, 0x11);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x26, 0xEC);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x24, 0x18);
-	CODEC_RegSelect(0x67);
 	CODEC_RegWrite(0x25, 0x53);
 
-	CODEC_RegSelect(0x67);
 	CODEC_RegMask(0x26, 0x80, 0x80);
-	CODEC_RegSelect(0x67);
 	CODEC_RegMask(0x24, 0x00, 0x80);
-	CODEC_RegSelect(0x67);
 	CODEC_RegMask(0x25, 0x10, 0x3C);
 }
 
 void CODEC_GetRawData(u32 *buffer)
 {
-	CODEC_RegSelect(0x67);
-	CODEC_RegRead(0x26);
 	CODEC_RegSelect(0xFB);
 	CODEC_RegReadBuf(1, buffer, 0x34);
 }

arm11/source/hw/i2c.c

@@ -52,7 +52,7 @@ static const struct
 	{1, 0x2E},
 	{1, 0x40},
 	{1, 0x44},
-	{2, 0xA6}, // TODO: Find out if 0xA6 or 0xD6 is correct
+	{2, 0xD6},
 	{2, 0xD0},
 	{2, 0xD2},
 	{2, 0xA4},

arm9/source/common/hid.c

@@ -31,13 +31,16 @@ static fixp_t ts_mult[2];
 
 // ts_org indicates the coordinate system origin
 static int ts_org[2];
-void HID_ReadTouchState(u16 *x, u16 *y)
+bool HID_ReadTouchState(u16 *x, u16 *y)
 {
     u32 ts;
     int xc, yc;
     fixp_t tx, ty;
 
     ts = HID_ReadRawTouchState();
+    if (ts & BIT(31))
+        return false;
+
     tx = INT_TO_FIXP(HID_RAW_TX(ts) - HID_TOUCH_MIDPOINT);
     ty = INT_TO_FIXP(HID_RAW_TY(ts) - HID_TOUCH_MIDPOINT);
 
@@ -46,6 +49,7 @@ void HID_ReadTouchState(u16 *x, u16 *y)
 
     *x = clamp(xc, 0, (ts_org[0] * 2) - 1);
     *y = clamp(yc, 0, (ts_org[1] * 2) - 1);
+    return true;
 }
 
 bool HID_SetCalibrationData(const HID_CalibrationData *calibs, int point_cnt, int screen_w, int screen_h)

arm9/source/common/hid.h

@@ -23,7 +23,7 @@ typedef struct {
 } HID_CalibrationData;
 
 u32 HID_ReadRawTouchState(void);
-void HID_ReadTouchState(u16 *x, u16 *y);
+bool HID_ReadTouchState(u16 *x, u16 *y);
 bool HID_SetCalibrationData(const HID_CalibrationData *calibs, int point_cnt, int screen_w, int screen_h);
 
 u32 InputWait(u32 timeout_sec);

arm9/source/common/touchcal.c

@@ -117,10 +117,8 @@ bool CalibrateTouchFromFlash(void) {
     u32 fw_usercfg_buf[0x100 / 0x4];
     u8* fw_usercfg = (u8*) fw_usercfg_buf;
     spiflash_read(0x1FE00, 0x100, fw_usercfg);
-    if (getle16(fw_usercfg + 0x72) != crc16_quick(fw_usercfg, 0x70)) {
+    if (getle16(fw_usercfg + 0x72) != crc16_quick(fw_usercfg, 0x70))
-    	ShowPrompt(false, "ugh");
+    	return false;
-    	return false; 
-    }
 
     // get touchscreen calibration data from user settings
     u8 *ts_data = fw_usercfg + 0x58;