tty: serial: fsl_lpuart: Ignore TX/RX interrupts if DMA is enabled

In a mixed DMA/IRQ use-case (e.g.: DMA for TX, IRQ for RX), interrupt handler might try to handle Rx/Tx condition it shouldn't. Change the code to only handle TX/RX event if corresponding path isn't being handled by DMA. Signed-off-by: Andrey Smirnov <[email protected]> Cc: Stefan Agner <[email protected]> Cc: Chris Healy <[email protected]> Cc: Cory Tusar <[email protected]> Cc: Lucas Stach <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
adn770 · Sep 4, 2019 · 6798e90 · 6798e90
1 parent f7ec172
commit 6798e90
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
@@ -967,10 +967,10 @@ static irqreturn_t lpuart_int(int irq, void *dev_id)
 
 	sts = readb(sport->port.membase + UARTSR1);
 
-	if (sts & UARTSR1_RDRF)
+	if (sts & UARTSR1_RDRF && !sport->lpuart_dma_rx_use)
 		lpuart_rxint(sport);
 
-	if (sts & UARTSR1_TDRE)
+	if (sts & UARTSR1_TDRE && !sport->lpuart_dma_tx_use)
 		lpuart_txint(sport);
 
 	return IRQ_HANDLED;