As per Advisory 27 of AM437x Silicon errata document, Spurious UART interrupts may occur when DMA mode (FCR.DMA_MODE) is enabled. The Interrupt Controller flags that a UART interrupt has occurred; however, the associated IT_PENDING bit remains set to 1, indicating that no interrupt is pending. Acknowledge the spurious interrupts for every occurrence as workaround. Errata is applicable to all TI SoCs with this IP. Signed-off-by: Vignesh Raghavendra <vigneshr@xxxxxx> --- drivers/tty/serial/8250/8250_omap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 207759dfbff2..92508aaa961c 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1051,7 +1051,7 @@ static int omap_8250_dma_handle_irq(struct uart_port *port) iir = serial_port_in(port, UART_IIR); if (iir & UART_IIR_NO_INT) { serial8250_rpm_put(up); - return 0; + return IRQ_HANDLED; } spin_lock_irqsave(&port->lock, flags); -- 2.25.2