media: ite-cir: IR receiver stop working after receive overflow

commit fdc8817 upstream.

On an Intel NUC6iSYK, no IR is reported after a receive overflow.

When a receiver overflow occurs, this condition is only cleared by
reading the fifo. Make sure we read anything in the fifo.

Fixes: 28c7afb ("media: ite-cir: check for receive overflow")
Suggested-by: Bryan Pass <bryan.pass@gmail.com>
Tested-by: Bryan Pass <bryan.pass@gmail.com>
Cc: stable@vger.kernel.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/media/rc/ite-cir.c

@@ -242,7 +242,7 @@ static irqreturn_t ite_cir_isr(int irq, void *data)
 	}
 
 	/* check for the receive interrupt */
-	if (iflags & ITE_IRQ_RX_FIFO) {
+	if (iflags & (ITE_IRQ_RX_FIFO | ITE_IRQ_RX_FIFO_OVERRUN)) {
 		/* read the FIFO bytes */
 		rx_bytes = dev->params->get_rx_bytes(dev, rx_buf,
 						    ITE_RX_FIFO_LEN);