diff --git a/hardware/common/serial.c b/hardware/common/serial.c
index cd7002b8..822b4ccd 100644
--- a/hardware/common/serial.c
+++ b/hardware/common/serial.c
@@ -297,13 +297,13 @@ SR_PRIV int serial_set_params(int fd, int baudrate, int bits, int parity,
 	term.c_iflag &= ~IGNPAR;
 	term.c_cflag &= ~(PARODD | PARENB);
 	switch (parity) {
-	case 0:
+	case SERIAL_PARITY_NONE:
 		term.c_iflag |= IGNPAR;
 		break;
-	case 1:
+	case SERIAL_PARITY_EVEN:
 		term.c_cflag |= PARENB;
 		break;
-	case 2:
+	case SERIAL_PARITY_ODD:
 		term.c_cflag |= PARENB | PARODD;
 		break;
 	default:
diff --git a/hardware/openbench-logic-sniffer/ols.c b/hardware/openbench-logic-sniffer/ols.c
index fd932c57..65a04f1a 100644
--- a/hardware/openbench-logic-sniffer/ols.c
+++ b/hardware/openbench-logic-sniffer/ols.c
@@ -398,7 +398,7 @@ static int hw_init(const char *devinfo)
 		fd = serial_open(l->data, O_RDWR | O_NONBLOCK);
 		if (fd != -1) {
 			serial_params[devcnt] = serial_backup_params(fd);
-			serial_set_params(fd, 115200, 8, 0, 1, 2);
+			serial_set_params(fd, 115200, 8, SERIAL_PARITY_NONE, 1, 2);
 			ret = SR_OK;
 			for (i = 0; i < 5; i++) {
 				if ((ret = send_shortcommand(fd,
diff --git a/sigrok-internal.h b/sigrok-internal.h
index fde076bb..94ca2bc9 100644
--- a/sigrok-internal.h
+++ b/sigrok-internal.h
@@ -48,6 +48,9 @@ struct sr_usb_dev_inst {
 };
 #endif
 
+#define SERIAL_PARITY_NONE 0
+#define SERIAL_PARITY_EVEN 1
+#define SERIAL_PARITY_ODD  2
 struct sr_serial_dev_inst {
 	char *port;
 	int fd;