Fix XIAO RP2040, allow swapping HW units 0/1 (#606)

Add plumbing to allow `Wire`, `Serial1`, `SPI1` to map to the 2nd
hardware unit for devices where the PCB layout only brings out the
2nd port.

Fix the Seeedstudio XAIO pins

Fixes #594

Author: earlephilhower

cores/rp2040/SerialUART.cpp

@@ -350,18 +350,6 @@ SerialUART::operator bool() {
     return _running;
 }
 
-#if defined(PIN_SERIAL1_RTS)
-SerialUART Serial1(uart0, PIN_SERIAL1_TX, PIN_SERIAL1_RX, PIN_SERIAL1_RTS, PIN_SERIAL1_CTS);
-#else
-SerialUART Serial1(uart0, PIN_SERIAL1_TX, PIN_SERIAL1_RX);
-#endif
-
-#if defined(PIN_SERIAL2_RTS)
-SerialUART Serial2(uart1, PIN_SERIAL2_TX, PIN_SERIAL2_RX, PIN_SERIAL2_RTS, PIN_SERIAL2_CTS);
-#else
-SerialUART Serial2(uart1, PIN_SERIAL2_TX, PIN_SERIAL2_RX);
-#endif
-
 void arduino::serialEvent1Run(void) {
     if (serialEvent1 && Serial1.available()) {
         serialEvent1();
@@ -406,10 +394,38 @@ void __not_in_flash_func(SerialUART::_handleIRQ)(bool inIRQ) {
     }
 }
 
+#ifndef __SERIAL1_DEVICE
+#define __SERIAL1_DEVICE uart0
+#endif
+#ifndef __SERIAL2_DEVICE
+#define __SERIAL2_DEVICE uart1
+#endif
+
+#if defined(PIN_SERIAL1_RTS)
+SerialUART Serial1(__SERIAL1_DEVICE, PIN_SERIAL1_TX, PIN_SERIAL1_RX, PIN_SERIAL1_RTS, PIN_SERIAL1_CTS);
+#else
+SerialUART Serial1(__SERIAL1_DEVICE, PIN_SERIAL1_TX, PIN_SERIAL1_RX);
+#endif
+
+#if defined(PIN_SERIAL2_RTS)
+SerialUART Serial2(__SERIAL2_DEVICE, PIN_SERIAL2_TX, PIN_SERIAL2_RX, PIN_SERIAL2_RTS, PIN_SERIAL2_CTS);
+#else
+SerialUART Serial2(__SERIAL2_DEVICE, PIN_SERIAL2_TX, PIN_SERIAL2_RX);
+#endif
+
+
 static void __not_in_flash_func(_uart0IRQ)() {
-    Serial1._handleIRQ();
+    if (__SERIAL1_DEVICE == uart0) {
+        Serial1._handleIRQ();
+    } else {
+        Serial2._handleIRQ();
+    }
 }
 
 static void __not_in_flash_func(_uart1IRQ)() {
-    Serial2._handleIRQ();
+    if (__SERIAL2_DEVICE == uart1) {
+        Serial2._handleIRQ();
+    } else {
+        Serial1._handleIRQ();
+    }
 }

libraries/SPI/SPI.cpp renamed to libraries/SPI/src/SPI.cpp

@@ -307,5 +307,12 @@ void SPIClassRP2040::setClockDivider(uint8_t uc_div) {
     (void) uc_div; // no-op
 }
 
-SPIClassRP2040 SPI(spi0, PIN_SPI0_MISO, PIN_SPI0_SS, PIN_SPI0_SCK, PIN_SPI0_MOSI);
-SPIClassRP2040 SPI1(spi1, PIN_SPI1_MISO, PIN_SPI1_SS, PIN_SPI1_SCK, PIN_SPI1_MOSI);
+#ifndef __SPI0_DEVICE
+#define __SPI0_DEVICE spi0
+#endif
+#ifndef __SPI1_DEVICE
+#define __SPI1_DEVICE spi1
+#endif
+
+SPIClassRP2040 SPI(__SPI0_DEVICE, PIN_SPI0_MISO, PIN_SPI0_SS, PIN_SPI0_SCK, PIN_SPI0_MOSI);
+SPIClassRP2040 SPI1(__SPI1_DEVICE, PIN_SPI1_MISO, PIN_SPI1_SS, PIN_SPI1_SCK, PIN_SPI1_MOSI);

libraries/SPI/SPI.h renamed to libraries/SPI/src/SPI.h

@@ -377,5 +377,12 @@ void TwoWire::onRequest(void(*function)(void)) {
     _onRequestCallback = function;
 }
 
-TwoWire Wire(i2c0, PIN_WIRE0_SDA, PIN_WIRE0_SCL);
-TwoWire Wire1(i2c1, PIN_WIRE1_SDA, PIN_WIRE1_SCL);
+#ifndef __WIRE0_DEVICE
+#define __WIRE0_DEVICE i2c0
+#endif
+#ifndef __WIRE1_DEVICE
+#define __WIRE1_DEVICE i2c1
+#endif
+
+TwoWire Wire(__WIRE0_DEVICE, PIN_WIRE0_SDA, PIN_WIRE0_SCL);
+TwoWire Wire1(__WIRE1_DEVICE, PIN_WIRE1_SDA, PIN_WIRE1_SCL);

libraries/Wire/src/Wire.cpp

@@ -8,6 +8,27 @@
 #define PIN_LED_R      (17u)
 #define PIN_LED_G      (16u)
 #define PIN_LED_B      (25u)
+#define LED_BUILTIN    PIN_LED
+
+// Digital pins
+static const uint8_t D0 = (26u);
+static const uint8_t D1 = (27u);
+static const uint8_t D2 = (28u);
+static const uint8_t D3 = (29u);
+static const uint8_t D4 = (6u);
+static const uint8_t D5 = (7u);
+static const uint8_t D6 = (0u);
+static const uint8_t D7 = (1u);
+static const uint8_t D8 = (2u);
+static const uint8_t D9 = (4u);
+static const uint8_t D10 = (3u);
+
+// Analog pins
+static const uint8_t A0  = (26u);
+static const uint8_t A1  = (27u);
+static const uint8_t A2  = (28u);
+static const uint8_t A3  = (29u);
+#define ADC_RESOLUTION 12
 
 // NeoPixel
 #define PIN_NEOPIXEL   (12u)
@@ -26,23 +47,34 @@
 #define PIN_SPI0_MOSI  (3u)
 #define PIN_SPI0_SCK   (2u)
 #define PIN_SPI0_SS    (31u) // not pinned out
+static const uint8_t SS   = PIN_SPI0_SS;   // SPI Slave SS not used. Set here only for reference.
+static const uint8_t MOSI = PIN_SPI0_MOSI;
+static const uint8_t MISO = PIN_SPI0_MISO;
+static const uint8_t SCK  = PIN_SPI0_SCK;
 
 // Not pinned out
 #define PIN_SPI1_MISO  (31u)
 #define PIN_SPI1_MOSI  (31u)
 #define PIN_SPI1_SCK   (31u)
 #define PIN_SPI1_SS    (31u)
+#define SPI_MISO       (PIN_SPI1_MISO)
+#define SPI_MOSI       (PIN_SPI1_MOSI)
+#define SPI_SCK        (PIN_SPI1_SCK)
 
 // Wire
+#define __WIRE0_DEVICE (i2c1)
 #define PIN_WIRE0_SDA  (6u)
 #define PIN_WIRE0_SCL  (7u)
+#define SDA            PIN_WIRE0_SDA
+#define SCL            PIN_WIRE0_SCL
+#define I2C_SDA        (SDA)
+#define I2C_SCL        (SCL)
 
 // Wire1 not pinned out
+#define __WIRE1_DEVICE (i2c0)
 #define PIN_WIRE1_SDA  (31u)
 #define PIN_WIRE1_SCL  (31u)
 
-#define SERIAL_HOWMANY (2u)
+#define SERIAL_HOWMANY (1u)
 #define SPI_HOWMANY    (1u)
 #define WIRE_HOWMANY   (1u)
-
-#include "../generic/common.h"