drivers: serial: Disable interrupts in SCIF driver

SCIF uses interrups by LEVEL and TX interrupt is fired if FIFO is not
full. In this case interrupt is faired immediately after exit from ISR.
Disable interrupts in SCIF driver after DMA operation finished. We
don't need enabled interrupts if nothing to transmit.

Signed-off-by: Dmytro Semenets <[email protected]>
Reviewed-by: Oleksii Moisieiev <[email protected]>
Acked-by: Volodymyr Babchuk <[email protected]>
Acked-by: Dmytro Firsov <[email protected]>

drivers/serial/uart_scif.c

@@ -1011,6 +1011,8 @@ static void uart_scif_dma_replace_buffer(const struct device *dev)
 		return;
 	}
 
+	uart_scif_write_16(dev, SCSCR, uart_scif_read_16(dev, SCSCR) | SCSCR_RE | SCSCR_RIE);
+
 	/* Request next buffer */
 	scif_async_evt_rx_buf_request(data);
 }
@@ -1126,6 +1128,8 @@ static int uart_scif_async_tx_abort(const struct device *dev)
 {
 	struct uart_scif_data *data = dev->data;
 
+	/* Turn off TX Interrupts to prevent hung in ISR */
+	uart_scif_write_16(dev, SCSCR, uart_scif_read_16(dev, SCSCR) & ~(SCSCR_TIE));
 	(void)k_work_cancel_delayable(&data->dma_tx.timeout_work);
 	return 0;
 }
@@ -1228,6 +1232,8 @@ static void dma_tx_callback(const struct device *dev, void *user_data,
 	if (!dma_get_status(data->dma_tx.dma_dev, data->dma_tx.dma_channel, &stat)) {
 		data->dma_tx.counter = data->dma_tx.buffer_length - stat.pending_length;
 	}
+	/* Turn off TX Interrupts to prevent hung in ISR */
+	uart_scif_write_16(uart_dev, SCSCR, uart_scif_read_16(uart_dev, SCSCR) & ~(SCSCR_TIE));
 	scif_async_evt_tx_done(data);
 	K_SPINLOCK(&data->dma_tx.lock) {
 		data->dma_tx.buffer_length = 0;
@@ -1240,6 +1246,9 @@ static void dma_rx_callback(const struct device *dev, void *user_data,
 	const struct device *uart_dev = user_data;
 	struct uart_scif_data *data = uart_dev->data;
 
+	/* Turn off RX Interrupts to prevent hung in ISR */
+	uart_scif_write_16(uart_dev, SCSCR, uart_scif_read_16(uart_dev, SCSCR) & ~(SCSCR_RIE));
+
 	(void)k_work_cancel_delayable(&data->dma_rx.timeout_work);
 	if (status < 0) {
 		scif_async_evt_rx_err(data, status);