diff --git a/hardware/hantek-dso/api.c b/hardware/hantek-dso/api.c
index e6b87f85..c9310336 100644
--- a/hardware/hantek-dso/api.c
+++ b/hardware/hantek-dso/api.c
@@ -573,7 +573,8 @@ static void receive_transfer(struct libusb_transfer *transfer)
 	packet.payload = &analog;
 	/* TODO: support for 5xxx series 9-bit samples */
 	analog.num_samples = transfer->actual_length / 2;
-	analog.unit = SR_UNIT_VOLTAGE;
+	analog.mq = SR_MQ_VOLTAGE;
+	analog.unit = SR_UNIT_VOLT;
 	analog.data = g_try_malloc(analog.num_samples * sizeof(float) * num_probes);
 	data_offset = 0;
 	for (i = 0; i < analog.num_samples; i++) {
diff --git a/sigrok.h.in b/sigrok.h.in
index 3e6f24e8..1d1f8caf 100644
--- a/sigrok.h.in
+++ b/sigrok.h.in
@@ -167,9 +167,27 @@ enum {
 	SR_DF_FRAME_END,
 };
 
+/* sr_datafeed_analog.mq values */
+enum {
+	SR_MQ_VOLTAGE,
+	SR_MQ_CURRENT,
+	SR_MQ_RESISTANCE,
+	SR_MQ_CAPACITANCE,
+	SR_MQ_TEMPERATURE,
+	SR_MQ_FREQUENCY,
+	SR_MQ_DUTY_CYCLE,
+};
+
 /* sr_datafeed_analog.unit values */
 enum {
-	SR_UNIT_VOLTAGE,
+	SR_UNIT_VOLT,
+	SR_UNIT_AMPERE,
+	SR_UNIT_OHM,
+	SR_UNIT_FARAD,
+	SR_UNIT_CELSIUS,
+	SR_UNIT_KELVIN,
+	SR_UNIT_HERTZ,
+	SR_UNIT_PERCENTAGE,
 };
 
 struct sr_datafeed_packet {
@@ -199,7 +217,8 @@ struct sr_datafeed_meta_analog {
 
 struct sr_datafeed_analog {
 	int num_samples;
-	int unit;
+	int mq; /* Measured quantity (e.g. voltage, current, temperature) */
+	int unit; /* Unit in which the MQ is measured. */
 	float *data;
 };