diff --git a/spi.hpp b/spi.hpp
index d6e5c65..3b71fdf 100644
--- a/spi.hpp
+++ b/spi.hpp
@@ -17,14 +17,33 @@ class Spi {
 		CLKDIV_2X_2 = 4,
 		CLKDIV_2X_8 = 5,
 		CLKDIV_2X_32 = 6,
-		CLKDIV_2X_64 = 7
+		CLKDIV_2X_64 = 7,
 	};
 
-	enum class Mode { MODE_0 = 0, MODE_1 = 1, MODE_2 = 2, MODE_3 = 3 };
+	enum class Mode {
+		MODE_0 = 0,
+		MODE_1 = 1,
+		MODE_2 = 2,
+		MODE_3 = 3,
+	};
 
   private:
-	static void setCPOL(bool bCPOL);
-	static void setCPHA(bool bCPHA);
+	static void setCPOL(bool bCPOL)
+	{
+		if (bCPOL) {
+			SPCR |= (1 << CPOL);
+		} else {
+			SPCR &= ~(1 << CPOL);
+		}
+	}
+	static void setCPHA(bool bCPHA)
+	{
+		if (bCPHA) {
+			SPCR |= (1 << CPHA);
+		} else {
+			SPCR &= ~(1 << CPHA);
+		}
+	}
 
 	static io::Pin<io::P::B5> sm_cSCK;
 	static io::Pin<io::P::B4> sm_cMISO;
@@ -33,150 +52,110 @@ class Spi {
 
   public:
 	static void init(ClockDiv enmClockDiv = ClockDiv::CLKDIV_128, Mode enmMode = Mode::MODE_0, bool bMaster = true,
-	                 bool bLSBFirst = false, bool bMISOPullup = false);
-	static void deinit();
-	static void setClockDiv(ClockDiv enmClockDiv);
-	static void setMode(Mode enmMode);
-	static void setMaster(bool bMaster);
-	static void setBitOrder(bool bLSBFirst);
+	                 bool bLSBFirst = false, bool bMISOPullup = false)
+	{
+		if (bMaster) {
+			sm_cSS.write(true);
 
-	static uint8_t transfer(uint8_t ui8Data);
+			sm_cSCK.dir(io::Dir::OUT);
+			sm_cMISO.dir(io::Dir::IN);
+			sm_cMISO.pullup(bMISOPullup);
+			sm_cMOSI.dir(io::Dir::OUT);
+			sm_cSS.dir(io::Dir::OUT);
+		} else {
+			sm_cSCK.dir(io::Dir::IN);
+			sm_cMISO.dir(io::Dir::OUT);
+			sm_cMOSI.dir(io::Dir::IN);
+			sm_cSS.dir(io::Dir::IN);
+			sm_cSS.pullup(true);
+		}
 
-	static void select(bool bSelect);
-};
+		setClockDiv(enmClockDiv);
+		setMode(enmMode);
+		setMaster(bMaster);
+		setBitOrder(bLSBFirst);
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::setCPOL(bool bCPOL)
-{
-	if (bCPOL) {
-		SPCR |= (1 << CPOL);
-	} else {
-		SPCR &= ~(1 << CPOL);
+		SPCR |= (1 << SPE);
 	}
-}
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::setCPHA(bool bCPHA)
-{
-	if (bCPHA) {
-		SPCR |= (1 << CPHA);
-	} else {
-		SPCR &= ~(1 << CPHA);
-	}
-}
+	static void deinit()
+	{
+		SPCR = 0;
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::init(ClockDiv enmClockDiv /* = ClockDiv::CLKDIV_128 */, Mode enmMode /* = Mode::MODE_0 */,
-               bool bMaster /* = true */, bool bLSBFirst /* = false */, bool bMISOPullup /* = false */)
-{
-	if (bMaster) {
-		sm_cSS.write(true);
-
-		sm_cSCK.dir(io::Dir::OUT);
-		sm_cMISO.dir(io::Dir::IN);
-		sm_cMISO.pullup(bMISOPullup);
-		sm_cMOSI.dir(io::Dir::OUT);
-		sm_cSS.dir(io::Dir::OUT);
-	} else {
 		sm_cSCK.dir(io::Dir::IN);
-		sm_cMISO.dir(io::Dir::OUT);
+		sm_cMISO.dir(io::Dir::IN);
 		sm_cMOSI.dir(io::Dir::IN);
 		sm_cSS.dir(io::Dir::IN);
-		sm_cSS.pullup(true);
 	}
 
-	setClockDiv(enmClockDiv);
-	setMode(enmMode);
-	setMaster(bMaster);
-	setBitOrder(bLSBFirst);
+	static void setClockDiv(ClockDiv enmClockDiv)
+	{
+		uint8_t ui8ClockDiv = static_cast<uint8_t>(enmClockDiv);
 
-	SPCR |= (1 << SPE);
-}
+		if (ui8ClockDiv & 1) {
+			SPCR |= (1 << SPR0);
+		} else {
+			SPCR &= ~(1 << SPR0);
+		}
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::deinit()
-{
-	SPCR = 0;
+		if (ui8ClockDiv & (1 << 1)) {
+			SPCR |= (1 << SPR1);
+		} else {
+			SPCR &= ~(1 << SPR1);
+		}
 
-	sm_cSCK.dir(io::Dir::IN);
-	sm_cMISO.dir(io::Dir::IN);
-	sm_cMOSI.dir(io::Dir::IN);
-	sm_cSS.dir(io::Dir::IN);
-}
-
-//////////////////////////////////////////////////////////////////////////
-void Spi::setClockDiv(ClockDiv enmClockDiv)
-{
-	uint8_t ui8ClockDiv = static_cast<uint8_t>(enmClockDiv);
-
-	if (ui8ClockDiv & 1) {
-		SPCR |= (1 << SPR0);
-	} else {
-		SPCR &= ~(1 << SPR0);
+		if (ui8ClockDiv & (1 << 2)) {
+			SPSR |= (1 << SPI2X);
+		} else {
+			SPSR &= ~(1 << SPI2X);
+		}
 	}
 
-	if (ui8ClockDiv & (1 << 1)) {
-		SPCR |= (1 << SPR1);
-	} else {
-		SPCR &= ~(1 << SPR1);
+	static void setMode(Mode enmMode)
+	{
+		if (enmMode == Mode::MODE_0 || enmMode == Mode::MODE_1) {
+			setCPOL(false);
+		} else {
+			setCPOL(true);
+		}
+
+		if (enmMode == Mode::MODE_0 || enmMode == Mode::MODE_2) {
+			setCPHA(false);
+		} else {
+			setCPHA(true);
+		}
 	}
 
-	if (ui8ClockDiv & (1 << 2)) {
-		SPSR |= (1 << SPI2X);
-	} else {
-		SPSR &= ~(1 << SPI2X);
-	}
-}
-
-//////////////////////////////////////////////////////////////////////////
-void Spi::setMode(Mode enmMode)
-{
-	if (enmMode == Mode::MODE_0 || enmMode == Mode::MODE_1) {
-		setCPOL(false);
-	} else {
-		setCPOL(true);
+	static void setMaster(bool bMaster)
+	{
+		if (bMaster) {
+			SPCR |= (1 << MSTR);
+		} else {
+			SPCR &= ~(1 << MSTR);
+		}
 	}
 
-	if (enmMode == Mode::MODE_0 || enmMode == Mode::MODE_2) {
-		setCPHA(false);
-	} else {
-		setCPHA(true);
+	static void setBitOrder(bool bLSBFirst)
+	{
+		if (bLSBFirst) {
+			SPCR |= (1 << DORD);
+		} else {
+			SPCR &= ~(1 << DORD);
+		}
 	}
-}
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::setMaster(bool bMaster)
-{
-	if (bMaster) {
-		SPCR |= (1 << MSTR);
-	} else {
-		SPCR &= ~(1 << MSTR);
+	static uint8_t transfer(uint8_t ui8Data)
+	{
+		SPDR = ui8Data;
+		while (!(SPSR & (1 << SPIF)))
+			;
+		return SPDR;
 	}
-}
 
-//////////////////////////////////////////////////////////////////////////
-void Spi::setBitOrder(bool bLSBFirst)
-{
-	if (bLSBFirst) {
-		SPCR |= (1 << DORD);
-	} else {
-		SPCR &= ~(1 << DORD);
+	static void select(bool bSelect)
+	{
+		sm_cSS.write(!bSelect);
 	}
-}
-
-//////////////////////////////////////////////////////////////////////////
-uint8_t Spi::transfer(uint8_t ui8Data)
-{
-	SPDR = ui8Data;
-	while (!(SPSR & (1 << SPIF)))
-		;
-	return SPDR;
-}
-
-//////////////////////////////////////////////////////////////////////////
-void Spi::select(bool bSelect)
-{
-	sm_cSS.write(!bSelect);
-}
+};
 
 } // namespace spi