Merge pull request #14 from KurtE/T4_setSCL_setSDA

T4 Wire1 has alternate pins - setSCL setSDA implemented

WireIMXRT.cpp

@@ -9,16 +9,24 @@
 void TwoWire::begin(void)
 {
         // use 24 MHz clock
-        CCM_CSCDR2 = (CCM_CSCDR2 & ~CCM_CSCDR2_LPI2C_CLK_PODF(63)) | CCM_CSCDR2_LPI2C_CLK_SEL;
+    CCM_CSCDR2 = (CCM_CSCDR2 & ~CCM_CSCDR2_LPI2C_CLK_PODF(63)) | CCM_CSCDR2_LPI2C_CLK_SEL;
 	hardware.clock_gate_register |= hardware.clock_gate_mask;
-        port->MCR = LPI2C_MCR_RST;
-        setClock(100000);
-	hardware.sda_mux_register = hardware.sda_mux_value;
-	hardware.scl_mux_register = hardware.scl_mux_value;
-	hardware.sda_input_register = hardware.sda_input_value;
-	hardware.scl_input_register = hardware.scl_input_value;
-	hardware.sda_pad_register |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
-	hardware.scl_pad_register |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
+    port->MCR = LPI2C_MCR_RST;
+    setClock(100000);
+
+    // Setup SDA register
+	*(portControlRegister(hardware.sda_pins[sda_pin_index_].pin)) |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
+	*(portConfigRegister(hardware.sda_pins[sda_pin_index_].pin)) = hardware.sda_pins[sda_pin_index_].mux_val;
+	if (hardware.sda_pins[sda_pin_index_].select_input_register) {
+	 	*(hardware.sda_pins[sda_pin_index_].select_input_register) =  hardware.sda_pins[sda_pin_index_].select_val;		
+	}	
+
+	// setup SCL register
+	*(portControlRegister(hardware.scl_pins[scl_pin_index_].pin)) |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
+	*(portConfigRegister(hardware.scl_pins[scl_pin_index_].pin)) = hardware.scl_pins[scl_pin_index_].mux_val;
+	if (hardware.scl_pins[scl_pin_index_].select_input_register) {
+	 	*(hardware.scl_pins[scl_pin_index_].select_input_register) =  hardware.scl_pins[scl_pin_index_].select_val;		
+	}	
 }
 
 void TwoWire::begin(uint8_t address)
@@ -30,6 +38,54 @@ void TwoWire::end()
 {
 }
 
+void TwoWire::setSDA(uint8_t pin) {
+	if (pin == hardware.sda_pins[sda_pin_index_].pin) return;
+	uint32_t newindex=0;
+	while (1) {
+		uint32_t sda_pin = hardware.sda_pins[newindex].pin;
+		if (sda_pin == 255) return;
+		if (sda_pin == pin) break;
+		if (++newindex >= sizeof(hardware.sda_pins)) return;
+	}
+	if ((hardware.clock_gate_register & hardware.clock_gate_mask)) {
+		*(portConfigRegister(hardware.sda_pins[sda_pin_index_].pin)) = 5;	// hard to know what to go back to?
+
+		// setup new one...
+		*(portControlRegister(hardware.sda_pins[newindex].pin)) |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
+		*(portConfigRegister(hardware.sda_pins[newindex].pin)) = hardware.sda_pins[newindex].mux_val;
+		if (hardware.sda_pins[newindex].select_input_register) {
+		 	*(hardware.sda_pins[newindex].select_input_register) =  hardware.sda_pins[newindex].select_val;		
+		}	
+
+	}
+	sda_pin_index_ = newindex;
+
+}
+
+void TwoWire::setSCL(uint8_t pin) {
+	if (pin == hardware.scl_pins[scl_pin_index_].pin) return;
+	uint32_t newindex=0;
+	while (1) {
+		uint32_t scl_pin = hardware.scl_pins[newindex].pin;
+		if (scl_pin == 255) return;
+		if (scl_pin == pin) break;
+		if (++newindex >= sizeof(hardware.scl_pins)) return;
+	}
+	if ((hardware.clock_gate_register & hardware.clock_gate_mask)) {
+		*(portConfigRegister(hardware.scl_pins[scl_pin_index_].pin)) = 5;	// hard to know what to go back to?
+
+		// setup new one...
+		*(portControlRegister(hardware.scl_pins[newindex].pin)) |= IOMUXC_PAD_PKE | IOMUXC_PAD_PUE | IOMUXC_PAD_PUS(3);
+		*(portConfigRegister(hardware.scl_pins[newindex].pin)) = hardware.scl_pins[newindex].mux_val;
+		if (hardware.scl_pins[newindex].select_input_register) {
+		 	*(hardware.scl_pins[newindex].select_input_register) =  hardware.scl_pins[newindex].select_val;		
+		}	
+
+	}
+	scl_pin_index_ = newindex;
+
+}
+
 size_t TwoWire::write(uint8_t data)
 {
 	if (transmitting || slave_mode) {
@@ -249,16 +305,8 @@ uint8_t TwoWire::requestFrom(uint8_t addr, uint8_t qty, uint32_t iaddr, uint8_t
 PROGMEM
 constexpr TwoWire::I2C_Hardware_t TwoWire::i2c1_hardware = {
         CCM_CCGR2, CCM_CCGR2_LPI2C1(CCM_CCGR_ON),
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_01, // 18/A4  AD_B1_01  GPIO1.17  I2C1_SDA
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_00, // 19/A5  AD_B1_00  GPIO1.16  I2C1_SCL
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_01,
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_00,
-	IOMUXC_LPI2C1_SDA_SELECT_INPUT,
-	IOMUXC_LPI2C1_SCL_SELECT_INPUT,
-	3 | 0x10,
-	3 | 0x10,
-	1,
-	1,
+		{{18, 3 | 0x10, &IOMUXC_LPI2C1_SDA_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
+		{{19, 3 | 0x10, &IOMUXC_LPI2C1_SCL_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
         IRQ_LPI2C1
 };
 TwoWire Wire(&IMXRT_LPI2C1, TwoWire::i2c1_hardware);
@@ -266,16 +314,8 @@ TwoWire Wire(&IMXRT_LPI2C1, TwoWire::i2c1_hardware);
 PROGMEM
 constexpr TwoWire::I2C_Hardware_t TwoWire::i2c3_hardware = {
         CCM_CCGR2, CCM_CCGR2_LPI2C3(CCM_CCGR_ON),
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_06, // 17/A3  AD_B1_06  GPIO1.22  I2C3_SDA
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B1_07, // 16/A2  AD_B1_07  GPIO1.23  I2C3_SCL
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_06,
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B1_07,
-	IOMUXC_LPI2C3_SDA_SELECT_INPUT,
-	IOMUXC_LPI2C3_SCL_SELECT_INPUT,
-	1 | 0x10,
-	1 | 0x10,
-	2,
-	2,
+		{{17, 1 | 0x10, &IOMUXC_LPI2C3_SDA_SELECT_INPUT, 2}, {36, 2 | 0x10, &IOMUXC_LPI2C3_SDA_SELECT_INPUT, 1}},
+		{{16, 1 | 0x10, &IOMUXC_LPI2C3_SCL_SELECT_INPUT, 2}, {37, 2 | 0x10, &IOMUXC_LPI2C3_SCL_SELECT_INPUT, 1}},
         IRQ_LPI2C3
 };
 TwoWire Wire1(&IMXRT_LPI2C3, TwoWire::i2c3_hardware);
@@ -283,16 +323,8 @@ TwoWire Wire1(&IMXRT_LPI2C3, TwoWire::i2c3_hardware);
 PROGMEM
 constexpr TwoWire::I2C_Hardware_t TwoWire::i2c4_hardware = {
         CCM_CCGR6, CCM_CCGR6_LPI2C4_SERIAL(CCM_CCGR_ON),
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_13, // 25/A11  AD_B0_13  GPIO1.13  I2C4_SDA
-	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_12, // 24/A10  AD_B1_12  GPIO1.12  I2C4_SCL
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_13,
-	IOMUXC_SW_PAD_CTL_PAD_GPIO_AD_B0_12,
-	IOMUXC_LPI2C4_SDA_SELECT_INPUT,
-	IOMUXC_LPI2C4_SCL_SELECT_INPUT,
-	0 | 0x10,
-	0 | 0x10,
-	1,
-	1,
+		{{25, 0 | 0x10, &IOMUXC_LPI2C4_SDA_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
+		{{24, 0 | 0x10, &IOMUXC_LPI2C4_SCL_SELECT_INPUT, 1}, {0xff, 0xff, nullptr, 0}},
         IRQ_LPI2C4
 };
 TwoWire Wire2(&IMXRT_LPI2C4, TwoWire::i2c4_hardware);

WireIMXRT.h

@@ -39,19 +39,20 @@ class TwoWire : public Stream
 {
 public:
 	// Hardware description struct
+	static const uint8_t cnt_sda_pins = 2;
+	static const uint8_t cnt_scl_pins = 2;
+	typedef struct {
+		const uint8_t 		pin;		// The pin number
+		const uint32_t 		mux_val;	// Value to set for mux;
+		volatile uint32_t	*select_input_register; // Which register controls the selection
+		const uint32_t		select_val;	// Value for that selection
+	} pin_info_t;
+
 	typedef struct {
 		volatile uint32_t &clock_gate_register;
 		uint32_t clock_gate_mask;
-		volatile uint32_t &sda_mux_register;
-		volatile uint32_t &scl_mux_register;
-		volatile uint32_t &sda_pad_register;
-		volatile uint32_t &scl_pad_register;
-		volatile uint32_t &sda_input_register;
-		volatile uint32_t &scl_input_register;
-		uint8_t sda_mux_value;
-		uint8_t scl_mux_value;
-		uint8_t sda_input_value;
-		uint8_t scl_input_value;
+		pin_info_t sda_pins[cnt_sda_pins];
+		pin_info_t scl_pins[cnt_scl_pins];
 		IRQ_NUMBER_t irq;
 	} I2C_Hardware_t;
 	static const I2C_Hardware_t i2c1_hardware;
@@ -69,10 +70,8 @@ public:
 	}
 	void end();
 	void setClock(uint32_t frequency);
-	void setSDA(uint8_t pin) {
-	}
-	void setSCL(uint8_t pin) {
-	}
+	void setSDA(uint8_t pin);
+	void setSCL(uint8_t pin); 
 	void beginTransmission(uint8_t address) {
 		txBuffer[0] = (address << 1);
 		transmitting = 1;
@@ -154,6 +153,8 @@ private:
 	//bool wait_idle(void);
 	IMXRT_LPI2C_t * const port;
 	const I2C_Hardware_t &hardware;
+	uint8_t	sda_pin_index_ = 0x0;	// default is always first item
+	uint8_t	scl_pin_index_ = 0x0;
 	uint8_t rxBuffer[BUFFER_LENGTH] = {};
 	uint8_t rxBufferIndex = 0;
 	uint8_t rxBufferLength = 0;