diff --git a/src/hardware/agilent-dmm/api.c b/src/hardware/agilent-dmm/api.c
index 7bafabc2..b5ba7ae2 100644
--- a/src/hardware/agilent-dmm/api.c
+++ b/src/hardware/agilent-dmm/api.c
@@ -166,10 +166,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
diff --git a/src/hardware/appa-55ii/api.c b/src/hardware/appa-55ii/api.c
index 0574a487..09b24cb2 100644
--- a/src/hardware/appa-55ii/api.c
+++ b/src/hardware/appa-55ii/api.c
@@ -149,10 +149,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
diff --git a/src/hardware/brymen-bm86x/api.c b/src/hardware/brymen-bm86x/api.c
index 345532e7..afed5771 100644
--- a/src/hardware/brymen-bm86x/api.c
+++ b/src/hardware/brymen-bm86x/api.c
@@ -184,10 +184,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->sw_limits, key, data);
 }
diff --git a/src/hardware/brymen-dmm/api.c b/src/hardware/brymen-dmm/api.c
index e9e534df..4d70e9ed 100644
--- a/src/hardware/brymen-dmm/api.c
+++ b/src/hardware/brymen-dmm/api.c
@@ -137,10 +137,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->sw_limits, key, data);
 }
diff --git a/src/hardware/cem-dt-885x/api.c b/src/hardware/cem-dt-885x/api.c
index f9ecc7cc..e31eaf2a 100644
--- a/src/hardware/cem-dt-885x/api.c
+++ b/src/hardware/cem-dt-885x/api.c
@@ -217,10 +217,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	ret = SR_OK;
 	switch (key) {
diff --git a/src/hardware/chronovu-la/api.c b/src/hardware/chronovu-la/api.c
index ae326772..932c9430 100644
--- a/src/hardware/chronovu-la/api.c
+++ b/src/hardware/chronovu-la/api.c
@@ -351,8 +351,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv))
-		return SR_ERR_BUG;
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_SAMPLERATE:
diff --git a/src/hardware/colead-slm/api.c b/src/hardware/colead-slm/api.c
index 33f27614..ac13da99 100644
--- a/src/hardware/colead-slm/api.c
+++ b/src/hardware/colead-slm/api.c
@@ -102,10 +102,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->limits, key, data);
 }
diff --git a/src/hardware/fluke-dmm/api.c b/src/hardware/fluke-dmm/api.c
index 0b2f7ffb..61da487b 100644
--- a/src/hardware/fluke-dmm/api.c
+++ b/src/hardware/fluke-dmm/api.c
@@ -194,10 +194,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
diff --git a/src/hardware/gmc-mh-1x-2x/protocol.c b/src/hardware/gmc-mh-1x-2x/protocol.c
index 1607bfa4..e116244e 100644
--- a/src/hardware/gmc-mh-1x-2x/protocol.c
+++ b/src/hardware/gmc-mh-1x-2x/protocol.c
@@ -1519,10 +1519,7 @@ SR_PRIV int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *s
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_POWER_OFF:
diff --git a/src/hardware/gwinstek-gds-800/api.c b/src/hardware/gwinstek-gds-800/api.c
index 57ca4fad..4c5e896f 100644
--- a/src/hardware/gwinstek-gds-800/api.c
+++ b/src/hardware/gwinstek-gds-800/api.c
@@ -148,12 +148,14 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 
 	(void)cg;
 
-	if (!sdi || !(devc = sdi->priv))
+	if (!sdi)
 		return SR_ERR_ARG;
 
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
+	devc = sdi->priv;
+
 	switch (key) {
 	case SR_CONF_LIMIT_FRAMES:
 		devc->frame_limit = g_variant_get_uint64(data);
diff --git a/src/hardware/hameg-hmo/api.c b/src/hardware/hameg-hmo/api.c
index b89de8d8..afe64891 100644
--- a/src/hardware/hameg-hmo/api.c
+++ b/src/hardware/hameg-hmo/api.c
@@ -318,9 +318,11 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	double tmp_d;
 	gboolean update_sample_rate;
 
-	if (!sdi || !(devc = sdi->priv))
+	if (!sdi)
 		return SR_ERR_ARG;
 
+	devc = sdi->priv;
+
 	if ((cg_type = check_channel_group(devc, cg)) == CG_INVALID)
 		return SR_ERR;
 
diff --git a/src/hardware/kern-scale/api.c b/src/hardware/kern-scale/api.c
index 432f3daa..6ec40a62 100644
--- a/src/hardware/kern-scale/api.c
+++ b/src/hardware/kern-scale/api.c
@@ -125,8 +125,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv))
-		return SR_ERR_BUG;
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->limits, key, data);
 }
diff --git a/src/hardware/link-mso19/api.c b/src/hardware/link-mso19/api.c
index 137deae6..f6353830 100644
--- a/src/hardware/link-mso19/api.c
+++ b/src/hardware/link-mso19/api.c
@@ -284,6 +284,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	double pos;
 
 	(void)cg;
+
 	devc = sdi->priv;
 
 	if (sdi->status != SR_ST_ACTIVE)
diff --git a/src/hardware/norma-dmm/api.c b/src/hardware/norma-dmm/api.c
index 8ca269c5..78011143 100644
--- a/src/hardware/norma-dmm/api.c
+++ b/src/hardware/norma-dmm/api.c
@@ -192,10 +192,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->limits, key, data);
 }
diff --git a/src/hardware/rigol-ds/api.c b/src/hardware/rigol-ds/api.c
index 7f45e187..c380c330 100644
--- a/src/hardware/rigol-ds/api.c
+++ b/src/hardware/rigol-ds/api.c
@@ -632,8 +632,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	const char *tmp_str;
 	char buffer[16];
 
-	if (!(devc = sdi->priv))
-		return SR_ERR_ARG;
+	devc = sdi->priv;
 
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
diff --git a/src/hardware/serial-dmm/api.c b/src/hardware/serial-dmm/api.c
index 9007789c..a272cca2 100644
--- a/src/hardware/serial-dmm/api.c
+++ b/src/hardware/serial-dmm/api.c
@@ -151,10 +151,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->limits, key, data);
 }
diff --git a/src/hardware/teleinfo/api.c b/src/hardware/teleinfo/api.c
index 9e64caae..4bccde01 100644
--- a/src/hardware/teleinfo/api.c
+++ b/src/hardware/teleinfo/api.c
@@ -138,10 +138,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("sdi->priv was NULL.");
-		return SR_ERR_BUG;
-	}
+	devc = sdi->priv;
 
 	return sr_sw_limits_config_set(&devc->sw_limits, key, data);
 }
diff --git a/src/hardware/zeroplus-logic-cube/api.c b/src/hardware/zeroplus-logic-cube/api.c
index 2207e3da..6a593027 100644
--- a/src/hardware/zeroplus-logic-cube/api.c
+++ b/src/hardware/zeroplus-logic-cube/api.c
@@ -380,10 +380,7 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	if (sdi->status != SR_ST_ACTIVE)
 		return SR_ERR_DEV_CLOSED;
 
-	if (!(devc = sdi->priv)) {
-		sr_err("%s: sdi->priv was NULL", __func__);
-		return SR_ERR_ARG;
-	}
+	devc = sdi->priv;
 
 	switch (key) {
 	case SR_CONF_SAMPLERATE:
diff --git a/src/hwdriver.c b/src/hwdriver.c
index 0c668e05..7e16b82a 100644
--- a/src/hwdriver.c
+++ b/src/hwdriver.c
@@ -722,7 +722,8 @@ SR_API int sr_config_get(const struct sr_dev_driver *driver,
 /**
  * Set value of a configuration key in a device instance.
  *
- * @param[in] sdi The device instance.
+ * @param[in] sdi The device instance. Must not be NULL. sdi->driver and
+ *                sdi->priv must not be NULL either.
  * @param[in] cg The channel group on the device for which to list the
  *                    values, or NULL.
  * @param[in] key The configuration key (SR_CONF_*).
@@ -746,7 +747,7 @@ SR_API int sr_config_set(const struct sr_dev_inst *sdi,
 
 	g_variant_ref_sink(data);
 
-	if (!sdi || !sdi->driver || !data)
+	if (!sdi || !sdi->driver || !sdi->priv || !data)
 		ret = SR_ERR;
 	else if (!sdi->driver->config_set)
 		ret = SR_ERR_ARG;