Remove peripheral clock changes as they interfere with current / old NuttX instance

src/drivers/px4io/px4io_serial.cpp

@@ -217,9 +217,6 @@ PX4IO_serial::~PX4IO_serial()
 	stm32_unconfiggpio(PX4IO_SERIAL_TX_GPIO);
 	stm32_unconfiggpio(PX4IO_SERIAL_RX_GPIO);
 
-	/* Disable APB clock for the USART peripheral */
-    modifyreg32(STM32_RCC_APB2ENR, RCC_APB2ENR_USART6EN, 0);
-
 	/* and kill our semaphores */
 	sem_destroy(&_completion_semaphore);
 	sem_destroy(&_bus_semaphore);
@@ -246,12 +243,9 @@ PX4IO_serial::init()
 	/* allocate DMA */
 	_tx_dma = stm32_dmachannel(PX4IO_SERIAL_TX_DMAMAP);
 	_rx_dma = stm32_dmachannel(PX4IO_SERIAL_RX_DMAMAP);
-	if ((_tx_dma == nullptr) || (_rx_dma == nullptr))
+	if ((_tx_dma == nullptr) || (_rx_dma == nullptr)) {
 		return -1;
-
-
-	/* Enable the APB clock for the USART peripheral */
-    modifyreg32(STM32_RCC_APB2ENR, 0, RCC_APB2ENR_USART6EN);
+	}
 
 	/* configure pins for serial use */
 	stm32_configgpio(PX4IO_SERIAL_TX_GPIO);