stm32: Harmonization of UART logic

src/machine/machine_stm32l5x2.go

@@ -6,25 +6,16 @@ package machine
 
 import (
 	"device/stm32"
-	"runtime/interrupt"
 )
 
 func CPUFrequency() uint32 {
 	return 110000000
 }
 
-//---------- UART related types and code
-
-// UART representation
-type UART struct {
-	Buffer          *RingBuffer
-	Bus             *stm32.USART_Type
-	Interrupt       interrupt.Interrupt
-	AltFuncSelector stm32.AltFunc
-}
+//---------- UART related code
 
 // Configure the UART.
-func (uart UART) configurePins(config UARTConfig) {
+func (uart *UART) configurePins(config UARTConfig) {
 	if config.RX.getPort() == stm32.GPIOG || config.TX.getPort() == stm32.GPIOG {
 		// Enable VDDIO2 power supply, which is an independant power supply for the PGx pins
 		stm32.PWR.CR2.SetBits(stm32.PWR_CR2_IOSV)
@@ -37,6 +28,14 @@ func (uart UART) configurePins(config UARTConfig) {
 
 // UART baudrate calc based on the bus and clockspeed
 // NOTE: keep this in sync with the runtime/runtime_stm32l5x2.go clock init code
-func (uart UART) getBaudRateDivisor(baudRate uint32) uint32 {
+func (uart *UART) getBaudRateDivisor(baudRate uint32) uint32 {
 	return 256 * (CPUFrequency() / baudRate)
 }
+
+// Register names vary by ST processor, these are for STM L5
+func (uart *UART) setRegisters() {
+	uart.rxReg = &uart.Bus.RDR
+	uart.txReg = &uart.Bus.TDR
+	uart.statusReg = &uart.Bus.ISR
+	uart.txEmptyFlag = stm32.USART_ISR_TXE
+}