serial: sc16is7xx: Don't spin if no data received

pelwell · popcornmix · commit 2949174b331e · 2025-03-24T19:27:05.000Z
There are multiple causes of interrupts, errors being one, and only the receipt of data warrants continued polling. See: #2676 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
@@ -821,6 +821,8 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 
 		if (rxlen)
 			sc16is7xx_handle_rx(port, rxlen, iir);
+		else
+			rc = false;
 		break;
 		/* CTSRTS interrupt comes only when CTS goes inactive */
 	case SC16IS7XX_IIR_CTSRTS_SRC:
