diff --git a/include/libsigrok/libsigrok.h b/include/libsigrok/libsigrok.h
index 3ecc460a..c029f117 100644
--- a/include/libsigrok/libsigrok.h
+++ b/include/libsigrok/libsigrok.h
@@ -486,7 +486,7 @@ struct sr_channel_group {
 /** Used for setting or getting value of a config item. */
 struct sr_config {
 	/** Config key like SR_CONF_CONN, etc. */
-	int key;
+	uint32_t key;
 	/** Key-specific data. */
 	GVariant *data;
 };
@@ -494,7 +494,7 @@ struct sr_config {
 /** Information about a config key. */
 struct sr_config_info {
 	/** Config key like SR_CONF_CONN, etc. */
-	int key;
+	uint32_t key;
 	/** Data type like SR_T_STRING, etc. */
 	int datatype;
 	/** Id string, e.g. "serialcomm". */
@@ -930,12 +930,12 @@ struct sr_dev_driver {
 	/** Query value of a configuration key in driver or given device instance.
 	 *  @see sr_config_get().
 	 */
-	int (*config_get) (int id, GVariant **data,
+	int (*config_get) (uint32_t key, GVariant **data,
 			const struct sr_dev_inst *sdi,
 			const struct sr_channel_group *cg);
 	/** Set value of a configuration key in driver or a given device instance.
 	 *  @see sr_config_set(). */
-	int (*config_set) (int id, GVariant *data,
+	int (*config_set) (uint32_t key, GVariant *data,
 			const struct sr_dev_inst *sdi,
 			const struct sr_channel_group *cg);
 	/** Channel status change.
@@ -948,7 +948,7 @@ struct sr_dev_driver {
 	/** List all possible values for a configuration key in a device instance.
 	 *  @see sr_config_list().
 	 */
-	int (*config_list) (int info_id, GVariant **data,
+	int (*config_list) (uint32_t key, GVariant **data,
 			const struct sr_dev_inst *sdi,
 			const struct sr_channel_group *cg);
 
diff --git a/include/libsigrok/proto.h b/include/libsigrok/proto.h
index e8aa7ab1..68e7a1ab 100644
--- a/include/libsigrok/proto.h
+++ b/include/libsigrok/proto.h
@@ -64,16 +64,16 @@ SR_API GSList *sr_driver_scan(struct sr_dev_driver *driver, GSList *options);
 SR_API int sr_config_get(const struct sr_dev_driver *driver,
 		const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant **data);
+		uint32_t key, GVariant **data);
 SR_API int sr_config_set(const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant *data);
+		uint32_t key, GVariant *data);
 SR_API int sr_config_commit(const struct sr_dev_inst *sdi);
 SR_API int sr_config_list(const struct sr_dev_driver *driver,
 		const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant **data);
-SR_API const struct sr_config_info *sr_config_info_get(int key);
+		uint32_t key, GVariant **data);
+SR_API const struct sr_config_info *sr_config_info_get(uint32_t key);
 SR_API const struct sr_config_info *sr_config_info_name_get(const char *optname);
 
 /*--- session.c -------------------------------------------------------------*/
diff --git a/src/hardware/agilent-dmm/api.c b/src/hardware/agilent-dmm/api.c
index 55f87416..df2d94e8 100644
--- a/src/hardware/agilent-dmm/api.c
+++ b/src/hardware/agilent-dmm/api.c
@@ -27,12 +27,12 @@
 #include "libsigrok-internal.h"
 #include "agilent-dmm.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -178,7 +178,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -193,7 +193,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_BUG;
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
 		/* TODO: not yet implemented */
 		if (g_variant_get_uint64(data) == 0) {
@@ -216,7 +216,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -224,12 +224,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/appa-55ii/api.c b/src/hardware/appa-55ii/api.c
index de71e338..f57a3b90 100644
--- a/src/hardware/appa-55ii/api.c
+++ b/src/hardware/appa-55ii/api.c
@@ -20,12 +20,12 @@
 #include <string.h>
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_THERMOMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -137,7 +137,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc = sdi->priv;
@@ -161,7 +161,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -205,7 +205,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -213,12 +213,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_DATA_SOURCE:
 		*data = g_variant_new_strv(data_sources, ARRAY_SIZE(data_sources));
diff --git a/src/hardware/asix-sigma/asix-sigma.c b/src/hardware/asix-sigma/asix-sigma.c
index bfd69484..55c6026c 100644
--- a/src/hardware/asix-sigma/asix-sigma.c
+++ b/src/hardware/asix-sigma/asix-sigma.c
@@ -71,7 +71,7 @@ static const char *channel_names[] = {
 	"9", "10", "11", "12", "13", "14", "15", "16",
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -813,7 +813,7 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -824,7 +824,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 		return SR_ERR;
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		*data = g_variant_new_uint64(devc->cur_samplerate);
 		break;
@@ -841,7 +841,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -856,7 +856,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	devc = sdi->priv;
 
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		ret = set_samplerate(sdi, g_variant_get_uint64(data));
 		break;
@@ -885,7 +885,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar;
@@ -896,8 +896,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
@@ -907,7 +907,7 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		*data = g_variant_builder_end(&gvb);
 		break;
 	case SR_CONF_TRIGGER_MATCH:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 				trigger_matches, ARRAY_SIZE(trigger_matches),
 				sizeof(int32_t));
 		break;
diff --git a/src/hardware/atten-pps3xxx/api.c b/src/hardware/atten-pps3xxx/api.c
index b6eae3cc..0df8bcf0 100644
--- a/src/hardware/atten-pps3xxx/api.c
+++ b/src/hardware/atten-pps3xxx/api.c
@@ -31,19 +31,19 @@
  */
 #define SERIALCOMM "9600/8n2"
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t devopts[] = {
+static const uint32_t devopts[] = {
 	SR_CONF_POWER_SUPPLY,
 	SR_CONF_CONTINUOUS,
 	SR_CONF_OUTPUT_CHANNEL_CONFIG,
 	SR_CONF_OVER_CURRENT_PROTECTION_ENABLED,
 };
 
-static const int32_t devopts_cg[] = {
+static const uint32_t devopts_cg[] = {
 	SR_CONF_OUTPUT_VOLTAGE,
 	SR_CONF_OUTPUT_VOLTAGE_MAX,
 	SR_CONF_OUTPUT_CURRENT,
@@ -205,7 +205,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -274,7 +274,7 @@ static int find_str(const char *str, const char **strings, int array_size)
 	return idx;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -358,7 +358,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -369,8 +369,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	/* Always available, even without sdi. */
 	if (key == SR_CONF_SCAN_OPTIONS) {
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		return SR_OK;
 	}
 
@@ -383,8 +383,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		/* No channel group: global options. */
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-					devopts, ARRAY_SIZE(devopts), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+					devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
 			break;
 		case SR_CONF_OUTPUT_CHANNEL_CONFIG:
 			if (devc->model->channel_modes == CHANMODE_INDEPENDENT) {
@@ -408,8 +408,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-					devopts_cg, ARRAY_SIZE(devopts_cg), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+					devopts_cg, ARRAY_SIZE(devopts_cg), sizeof(uint32_t));
 			break;
 		case SR_CONF_OUTPUT_VOLTAGE_MAX:
 			g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
diff --git a/src/hardware/beaglelogic/api.c b/src/hardware/beaglelogic/api.c
index c86925be..b5850314 100644
--- a/src/hardware/beaglelogic/api.c
+++ b/src/hardware/beaglelogic/api.c
@@ -24,7 +24,7 @@ SR_PRIV struct sr_dev_driver beaglelogic_driver_info;
 static struct sr_dev_driver *di = &beaglelogic_driver_info;
 
 /* Hardware capabiities */
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -223,7 +223,7 @@ static int cleanup(void)
 	return SR_OK;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc = sdi->priv;
@@ -249,7 +249,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc = sdi->priv;
@@ -289,7 +289,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int ret;
@@ -303,8 +303,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	ret = SR_OK;
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
@@ -314,7 +314,7 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		*data = g_variant_builder_end(&gvb);
 		break;
 	case SR_CONF_TRIGGER_MATCH:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 				soft_trigger_matches, ARRAY_SIZE(soft_trigger_matches),
 				sizeof(int32_t));
 		break;
diff --git a/src/hardware/brymen-bm86x/api.c b/src/hardware/brymen-bm86x/api.c
index be21583b..f47c01ed 100644
--- a/src/hardware/brymen-bm86x/api.c
+++ b/src/hardware/brymen-bm86x/api.c
@@ -21,11 +21,11 @@
 
 #define BRYMEN_BC86X "0820.0001"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -182,7 +182,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc = sdi->priv;
@@ -203,7 +203,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -234,7 +234,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -242,12 +242,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/brymen-dmm/api.c b/src/hardware/brymen-dmm/api.c
index 1ccd18af..f0ba3923 100644
--- a/src/hardware/brymen-dmm/api.c
+++ b/src/hardware/brymen-dmm/api.c
@@ -19,12 +19,12 @@
 
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_CONTINUOUS,
@@ -149,7 +149,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -166,7 +166,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	}
 
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
 		devc->limit_samples = g_variant_get_uint64(data);
 		break;
@@ -180,7 +180,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -188,12 +188,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/cem-dt-885x/api.c b/src/hardware/cem-dt-885x/api.c
index 9aed5473..943377a3 100644
--- a/src/hardware/cem-dt-885x/api.c
+++ b/src/hardware/cem-dt-885x/api.c
@@ -24,11 +24,11 @@
 /* 23ms is the longest interval between tokens. */
 #define MAX_SCAN_TIME 25 * 1000
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_SOUNDLEVELMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_CONTINUOUS,
@@ -165,7 +165,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -237,7 +237,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -327,7 +327,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *tuple, *range[2];
@@ -341,12 +341,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	ret = SR_OK;
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SPL_WEIGHT_FREQ:
 		*data = g_variant_new_strv(weight_freq, ARRAY_SIZE(weight_freq));
diff --git a/src/hardware/center-3xx/api.c b/src/hardware/center-3xx/api.c
index 0f80cf83..edaecd7b 100644
--- a/src/hardware/center-3xx/api.c
+++ b/src/hardware/center-3xx/api.c
@@ -20,12 +20,12 @@
 
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_THERMOMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -158,7 +158,7 @@ static int cleanup(int idx)
 	return dev_clear(idx);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -170,7 +170,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
 		if (g_variant_get_uint64(data) == 0)
 			return SR_ERR_ARG;
@@ -188,7 +188,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -196,12 +196,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/chronovu-la/api.c b/src/hardware/chronovu-la/api.c
index 5a8a3d36..f4b19894 100644
--- a/src/hardware/chronovu-la/api.c
+++ b/src/hardware/chronovu-la/api.c
@@ -23,7 +23,7 @@
 SR_PRIV struct sr_dev_driver chronovu_la_driver_info;
 static struct sr_dev_driver *di = &chronovu_la_driver_info;
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -285,14 +285,14 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
 
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		if (!sdi || !(devc = sdi->priv))
 			return SR_ERR_BUG;
@@ -305,7 +305,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -318,7 +318,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	if (!(devc = sdi->priv))
 		return SR_ERR_BUG;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		if (cv_set_samplerate(sdi, g_variant_get_uint64(data)) < 0)
 			return SR_ERR;
@@ -340,7 +340,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar, *grange[2];
@@ -351,8 +351,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		if (!sdi || !sdi->priv || !(devc = sdi->priv))
@@ -379,7 +379,7 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	case SR_CONF_TRIGGER_MATCH:
 		if (!sdi || !sdi->priv || !(devc = sdi->priv) || !devc->prof)
 			return SR_ERR_BUG;
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 				trigger_matches, devc->prof->num_trigger_matches,
 				sizeof(int32_t));
 		break;
diff --git a/src/hardware/colead-slm/api.c b/src/hardware/colead-slm/api.c
index d5fc9ac1..8e48552d 100644
--- a/src/hardware/colead-slm/api.c
+++ b/src/hardware/colead-slm/api.c
@@ -30,12 +30,12 @@
 /* The Colead SL-5868P uses this. */
 #define SERIALCOMM "2400/8n1"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_SOUNDLEVELMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -129,7 +129,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -144,7 +144,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_BUG;
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
 		/* TODO: not yet implemented */
 		if (g_variant_get_uint64(data) == 0) {
@@ -167,7 +167,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -175,12 +175,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/conrad-digi-35-cpu/api.c b/src/hardware/conrad-digi-35-cpu/api.c
index 6a1f31c9..a2a88159 100644
--- a/src/hardware/conrad-digi-35-cpu/api.c
+++ b/src/hardware/conrad-digi-35-cpu/api.c
@@ -26,12 +26,12 @@
 
 #define SERIALCOMM "9600/8n1"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_POWER_SUPPLY,
 	SR_CONF_OUTPUT_VOLTAGE,
 	SR_CONF_OUTPUT_CURRENT,
@@ -121,7 +121,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int ret;
@@ -164,7 +164,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int ret;
@@ -175,12 +175,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	ret = SR_OK;
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/demo/demo.c b/src/hardware/demo/demo.c
index 7fc959f4..d2fddde4 100644
--- a/src/hardware/demo/demo.c
+++ b/src/hardware/demo/demo.c
@@ -128,7 +128,7 @@ struct dev_context {
 	GHashTable *ch_ag;
 };
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_NUM_LOGIC_CHANNELS,
 	SR_CONF_NUM_ANALOG_CHANNELS,
 };
@@ -398,7 +398,7 @@ static int cleanup(void)
 	return std_dev_clear(di, clear_helper);
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -410,7 +410,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 		return SR_ERR_ARG;
 
 	devc = sdi->priv;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		*data = g_variant_new_uint64(devc->cur_samplerate);
 		break;
@@ -458,7 +458,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -475,7 +475,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_DEV_CLOSED;
 
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		devc->cur_samplerate = g_variant_get_uint64(data);
 		sr_dbg("Setting samplerate to %" PRIu64, devc->cur_samplerate);
@@ -552,7 +552,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct sr_channel *ch;
@@ -562,8 +562,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	(void)sdi;
 
 	if (key == SR_CONF_SCAN_OPTIONS) {
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		return SR_OK;
 	}
 
@@ -573,8 +573,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	if (!cg) {
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-					devopts, ARRAY_SIZE(devopts), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+					devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
 			break;
 		case SR_CONF_SAMPLERATE:
 			g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
@@ -594,11 +594,11 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 			if (ch->type == SR_CHANNEL_LOGIC)
 				*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
 						devopts_cg_logic, ARRAY_SIZE(devopts_cg_logic),
-						sizeof(int32_t));
+						sizeof(uint32_t));
 			else if (ch->type == SR_CHANNEL_ANALOG)
 				*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
 						devopts_cg_analog, ARRAY_SIZE(devopts_cg_analog),
-						sizeof(int32_t));
+						sizeof(uint32_t));
 			else
 				return SR_ERR_BUG;
 			break;
diff --git a/src/hardware/fluke-dmm/api.c b/src/hardware/fluke-dmm/api.c
index 3d739a18..50576557 100644
--- a/src/hardware/fluke-dmm/api.c
+++ b/src/hardware/fluke-dmm/api.c
@@ -27,12 +27,12 @@
 #include "libsigrok-internal.h"
 #include "fluke-dmm.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -203,7 +203,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -218,7 +218,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_BUG;
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
 		/* TODO: not yet implemented */
 		if (g_variant_get_uint64(data) == 0) {
@@ -241,7 +241,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -249,12 +249,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/fx2lafw/api.c b/src/hardware/fx2lafw/api.c
index d4643ff7..a233cbc8 100644
--- a/src/hardware/fx2lafw/api.c
+++ b/src/hardware/fx2lafw/api.c
@@ -73,11 +73,11 @@ static const struct fx2lafw_profile supported_fx2[] = {
 	{ 0, 0, 0, 0, 0, 0, 0, 0, 0 }
 };
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_TRIGGER_MATCH,
 	SR_CONF_SAMPLERATE,
@@ -385,7 +385,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -399,7 +399,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_CONN:
 		if (!sdi->conn)
 			return SR_ERR_ARG;
@@ -424,7 +424,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -444,8 +444,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	ret = SR_OK;
 
-	switch (id)
-	{
+	switch (key) {
 		case SR_CONF_SAMPLERATE:
 			arg = g_variant_get_uint64(data);
 			for (i = 0; i < ARRAY_SIZE(samplerates); i++) {
@@ -467,7 +466,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar;
@@ -478,12 +477,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/gmc-mh-1x-2x/api.c b/src/hardware/gmc-mh-1x-2x/api.c
index 96621bbf..f2d06c26 100644
--- a/src/hardware/gmc-mh-1x-2x/api.c
+++ b/src/hardware/gmc-mh-1x-2x/api.c
@@ -34,13 +34,13 @@
 SR_PRIV struct sr_dev_driver gmc_mh_1x_2x_rs232_driver_info;
 SR_PRIV struct sr_dev_driver gmc_mh_2x_bd232_driver_info;
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
 /** Hardware capabilities for Metrahit 1x/2x devices in send mode. */
-static const int32_t hwcaps_sm[] = {
+static const uint32_t hwcaps_sm[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_THERMOMETER,    /**< All GMC 1x/2x multimeters seem to support this */
 	SR_CONF_LIMIT_SAMPLES,
@@ -49,7 +49,7 @@ static const int32_t hwcaps_sm[] = {
 };
 
 /** Hardware capabilities for Metrahit 2x devices in bidirectional Mode. */
-static const int32_t hwcaps_bd[] = {
+static const uint32_t hwcaps_bd[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_THERMOMETER,    /**< All GMC 1x/2x multimeters seem to support this */
 	SR_CONF_LIMIT_SAMPLES,
@@ -422,8 +422,8 @@ static int cleanup_2x_bd232(void)
 }
 
 /** Get value of configuration item */
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
-		      const struct sr_channel_group *cg)
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
+		const struct sr_channel_group *cg)
 {
 	int ret;
 	struct dev_context *devc;
@@ -454,16 +454,16 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 }
 
 /** Implementation of config_list, auxiliary function for common parts, */
-static int config_list_common(int key, GVariant **data, const struct sr_dev_inst *sdi,
-			      const struct sr_channel_group *cg)
+static int config_list_common(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
+		const struct sr_channel_group *cg)
 {
 	(void)sdi;
 	(void)cg;
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-						  hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+						  hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
@@ -473,13 +473,13 @@ static int config_list_common(int key, GVariant **data, const struct sr_dev_inst
 }
 
 /** Implementation of config_list for Metrahit 1x/2x send mode */
-static int config_list_sm(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list_sm(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 			  const struct sr_channel_group *cg)
 {
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-						  hwcaps_sm, ARRAY_SIZE(hwcaps_sm), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+						  hwcaps_sm, ARRAY_SIZE(hwcaps_sm), sizeof(uint32_t));
 		break;
 	default:
 		return config_list_common(key, data, sdi, cg);
@@ -489,13 +489,13 @@ static int config_list_sm(int key, GVariant **data, const struct sr_dev_inst *sd
 }
 
 /** Implementation of config_list for Metrahit 2x bidirectional mode */
-static int config_list_bd(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list_bd(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 			  const struct sr_channel_group *cg)
 {
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-						  hwcaps_bd, ARRAY_SIZE(hwcaps_bd), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+						  hwcaps_bd, ARRAY_SIZE(hwcaps_bd), sizeof(uint32_t));
 		break;
 	default:
 		return config_list_common(key, data, sdi, cg);
diff --git a/src/hardware/gmc-mh-1x-2x/protocol.c b/src/hardware/gmc-mh-1x-2x/protocol.c
index bcdc93fc..06cae38b 100644
--- a/src/hardware/gmc-mh-1x-2x/protocol.c
+++ b/src/hardware/gmc-mh-1x-2x/protocol.c
@@ -1500,8 +1500,8 @@ SR_PRIV const char *gmc_model_str(enum model mcode)
 
 /** @copydoc sr_dev_driver.config_set
  */
-SR_PRIV int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
-		       const struct sr_channel_group *cg)
+SR_PRIV int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
+		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
 	uint8_t params[9];
diff --git a/src/hardware/gmc-mh-1x-2x/protocol.h b/src/hardware/gmc-mh-1x-2x/protocol.h
index 6f751224..3d0eab42 100644
--- a/src/hardware/gmc-mh-1x-2x/protocol.h
+++ b/src/hardware/gmc-mh-1x-2x/protocol.h
@@ -120,7 +120,7 @@ struct dev_context {
 };
 
 /* Forward declarations */
-SR_PRIV int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+SR_PRIV int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg);
 SR_PRIV void create_cmd_14(guchar addr, guchar func, guchar* params, guchar* buf);
 SR_PRIV void dump_msg14(guchar* buf, gboolean raw);
diff --git a/src/hardware/hameg-hmo/api.c b/src/hardware/hameg-hmo/api.c
index 8db1e76a..4950d89f 100644
--- a/src/hardware/hameg-hmo/api.c
+++ b/src/hardware/hameg-hmo/api.c
@@ -29,7 +29,7 @@ static const char *manufacturers[] = {
 	"HAMEG",
 };
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
@@ -196,7 +196,7 @@ static int check_channel_group(struct dev_context *devc,
 	return CG_INVALID;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		      const struct sr_channel_group *cg)
 {
 	int ret, cg_type;
@@ -320,7 +320,7 @@ static GVariant *build_tuples(const uint64_t (*array)[][2], unsigned int n)
 	return g_variant_builder_end(&gvb);
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		      const struct sr_channel_group *cg)
 {
 	int ret, cg_type;
@@ -492,7 +492,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		       const struct sr_channel_group *cg)
 {
 	int cg_type;
@@ -509,21 +509,21 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
 		if (cg_type == CG_NONE) {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 				model->hw_caps, model->num_hwcaps,
-				sizeof(int32_t));
+				sizeof(uint32_t));
 		} else if (cg_type == CG_ANALOG) {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 				model->analog_hwcaps, model->num_analog_hwcaps,
-				sizeof(int32_t));
+				sizeof(uint32_t));
 		} else {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				NULL, 0, sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				NULL, 0, sizeof(uint32_t));
 		}
 		break;
 	case SR_CONF_COUPLING:
diff --git a/src/hardware/hameg-hmo/protocol.c b/src/hardware/hameg-hmo/protocol.c
index 1a788407..a1cee6aa 100644
--- a/src/hardware/hameg-hmo/protocol.c
+++ b/src/hardware/hameg-hmo/protocol.c
@@ -45,7 +45,7 @@ static const char *hameg_scpi_dialect[] = {
 	[SCPI_CMD_SET_ANALOG_CHAN_STATE]    = ":CHAN%d:STAT %d",
 };
 
-static const int32_t hmo_hwcaps[] = {
+static const uint32_t hmo_hwcaps[] = {
 	SR_CONF_OSCILLOSCOPE,
 	SR_CONF_TRIGGER_SOURCE,
 	SR_CONF_TIMEBASE,
@@ -56,7 +56,7 @@ static const int32_t hmo_hwcaps[] = {
 	SR_CONF_LIMIT_FRAMES,
 };
 
-static const int32_t hmo_analog_caps[] = {
+static const uint32_t hmo_analog_caps[] = {
 	SR_CONF_NUM_VDIV,
 	SR_CONF_COUPLING,
 	SR_CONF_VDIV,
diff --git a/src/hardware/hameg-hmo/protocol.h b/src/hardware/hameg-hmo/protocol.h
index 932e3ec3..1df319e3 100644
--- a/src/hardware/hameg-hmo/protocol.h
+++ b/src/hardware/hameg-hmo/protocol.h
@@ -40,10 +40,10 @@ struct scope_config {
 	const char *(*analog_names)[];
 	const char *(*digital_names)[];
 
-	const int32_t (*hw_caps)[];
+	const uint32_t (*hw_caps)[];
 	const uint8_t num_hwcaps;
 
-	const int32_t (*analog_hwcaps)[];
+	const uint32_t (*analog_hwcaps)[];
 	const uint8_t num_analog_hwcaps;
 
 	const char *(*coupling_options)[];
diff --git a/src/hardware/hantek-dso/api.c b/src/hardware/hantek-dso/api.c
index c948e421..abc3c08e 100644
--- a/src/hardware/hantek-dso/api.c
+++ b/src/hardware/hantek-dso/api.c
@@ -40,11 +40,11 @@
 #define NUM_TIMEBASE  10
 #define NUM_VDIV      8
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t devopts[] = {
+static const uint32_t devopts[] = {
 	SR_CONF_OSCILLOSCOPE,
 	SR_CONF_LIMIT_FRAMES,
 	SR_CONF_CONTINUOUS,
@@ -422,7 +422,7 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct sr_usb_dev_inst *usb;
@@ -430,7 +430,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_CONN:
 		if (!sdi || !sdi->conn)
 			return SR_ERR_ARG;
@@ -455,7 +455,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -473,7 +473,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	ret = SR_OK;
 	devc = sdi->priv;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_FRAMES:
 		devc->limit_frames = g_variant_get_uint64(data);
 		break;
@@ -586,7 +586,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -598,12 +598,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				devopts, ARRAY_SIZE(devopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_BUFFERSIZE:
 		if (!sdi)
diff --git a/src/hardware/ikalogic-scanalogic2/api.c b/src/hardware/ikalogic-scanalogic2/api.c
index b4c697f9..25cebb5f 100644
--- a/src/hardware/ikalogic-scanalogic2/api.c
+++ b/src/hardware/ikalogic-scanalogic2/api.c
@@ -19,7 +19,7 @@
 
 #include "protocol.h"
 
-static const int hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_LIMIT_SAMPLES,
@@ -313,7 +313,7 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -338,7 +338,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	uint64_t samplerate, limit_samples, capture_ratio;
@@ -371,7 +371,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar, *grange[2];
@@ -385,8 +385,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32, hwcaps,
-			ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+			hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/ikalogic-scanaplus/api.c b/src/hardware/ikalogic-scanaplus/api.c
index ce00478e..e4ebb267 100644
--- a/src/hardware/ikalogic-scanaplus/api.c
+++ b/src/hardware/ikalogic-scanaplus/api.c
@@ -28,7 +28,7 @@
 
 #define SAMPLE_BUF_SIZE			(8 * 1024 * 1024)
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_LIMIT_MSEC,
@@ -280,13 +280,13 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		/* The ScanaPLUS samplerate is 100MHz and can't be changed. */
 		*data = g_variant_new_uint64(SR_MHZ(100));
@@ -298,7 +298,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -310,7 +310,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		if (g_variant_get_uint64(data) != SR_MHZ(100)) {
 			sr_err("ScanaPLUS only supports samplerate = 100MHz.");
@@ -335,7 +335,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar;
@@ -346,8 +346,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/kecheng-kc-330b/api.c b/src/hardware/kecheng-kc-330b/api.c
index 71bdc012..293d3c85 100644
--- a/src/hardware/kecheng-kc-330b/api.c
+++ b/src/hardware/kecheng-kc-330b/api.c
@@ -24,7 +24,7 @@
 #define VENDOR "Kecheng"
 #define USB_INTERFACE 0
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_SOUNDLEVELMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_CONTINUOUS,
@@ -248,7 +248,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -297,7 +297,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -377,7 +377,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *tuple, *rational[2];
@@ -389,8 +389,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLE_INTERVAL:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
diff --git a/src/hardware/lascar-el-usb/api.c b/src/hardware/lascar-el-usb/api.c
index 04f844b3..0ffe3f48 100644
--- a/src/hardware/lascar-el-usb/api.c
+++ b/src/hardware/lascar-el-usb/api.c
@@ -26,11 +26,11 @@
 SR_PRIV struct sr_dev_driver lascar_el_usb_driver_info;
 static struct sr_dev_driver *di = &lascar_el_usb_driver_info;
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_THERMOMETER,
 	SR_CONF_HYGROMETER,
 	SR_CONF_DATALOG,
@@ -158,7 +158,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -169,7 +169,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	(void)cg;
 
 	devc = sdi->priv;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_CONN:
 		if (!sdi || !sdi->conn)
 			return SR_ERR_ARG;
@@ -194,7 +194,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -212,7 +212,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_DATALOG:
 		if (g_variant_get_boolean(data)) {
 			/* Start logging. */
@@ -234,7 +234,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -242,12 +242,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/link-mso19/api.c b/src/hardware/link-mso19/api.c
index 13c29720..829530e0 100644
--- a/src/hardware/link-mso19/api.c
+++ b/src/hardware/link-mso19/api.c
@@ -21,7 +21,7 @@
 
 #include "protocol.h"
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_OSCILLOSCOPE,
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
@@ -380,8 +380,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/manson-hcs-3xxx/api.c b/src/hardware/manson-hcs-3xxx/api.c
index faa093f1..7218d9b5 100644
--- a/src/hardware/manson-hcs-3xxx/api.c
+++ b/src/hardware/manson-hcs-3xxx/api.c
@@ -26,12 +26,12 @@
 
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t devopts[] = {
+static const uint32_t devopts[] = {
 	/* Device class */
 	SR_CONF_POWER_SUPPLY,
 	/* Aquisition modes. */
@@ -216,7 +216,7 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -257,7 +257,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -320,7 +320,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -337,12 +337,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-			hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+			hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-			devopts, ARRAY_SIZE(devopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+			devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_OUTPUT_CURRENT_MAX:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
diff --git a/src/hardware/mic-985xx/api.c b/src/hardware/mic-985xx/api.c
index 39173145..0a1e2582 100644
--- a/src/hardware/mic-985xx/api.c
+++ b/src/hardware/mic-985xx/api.c
@@ -20,12 +20,12 @@
 
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_THERMOMETER,
 	SR_CONF_HYGROMETER,
 	SR_CONF_LIMIT_SAMPLES,
@@ -160,7 +160,7 @@ static int cleanup(int idx)
 	return dev_clear(idx);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -172,7 +172,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
 		devc->limit_samples = g_variant_get_uint64(data);
 		sr_dbg("Setting sample limit to %" PRIu64 ".",
@@ -190,7 +190,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -198,12 +198,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/motech-lps-30x/api.c b/src/hardware/motech-lps-30x/api.c
index ae08317a..a52b2f28 100644
--- a/src/hardware/motech-lps-30x/api.c
+++ b/src/hardware/motech-lps-30x/api.c
@@ -44,13 +44,13 @@ SR_PRIV int lps_query_status(struct sr_dev_inst* sdi);
 #define VENDOR_MOTECH "Motech"
 
 /** Driver scanning options. */
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
 /** Hardware capabilities generic. */
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	/* Device class */
 	SR_CONF_POWER_SUPPLY,
 	/* Aquisition modes. */
@@ -62,7 +62,7 @@ static const int32_t hwcaps[] = {
 };
 
 /** Hardware capabilities channel 1, 2. */
-static const int32_t hwcaps_ch12[] = {
+static const uint32_t hwcaps_ch12[] = {
 	SR_CONF_OUTPUT_VOLTAGE,
 	SR_CONF_OUTPUT_VOLTAGE_MAX,
 	SR_CONF_OUTPUT_CURRENT,
@@ -71,7 +71,7 @@ static const int32_t hwcaps_ch12[] = {
 };
 
 /** Hardware capabilities channel 3. (LPS-304/305 only). */
-static const int32_t hwcaps_ch3[] = {
+static const uint32_t hwcaps_ch3[] = {
 	SR_CONF_OUTPUT_VOLTAGE,
 	SR_CONF_OUTPUT_ENABLED,
 };
@@ -540,7 +540,7 @@ static int cleanup(void)
 	return dev_clear_lps301();
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -595,7 +595,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -717,7 +717,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -731,8 +731,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	/* Driver options, no device instance necessary. */
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-						  hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+						  hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		return SR_OK;
 	default:
 		if (sdi == NULL)
@@ -741,12 +741,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		devc = sdi->priv;
 	}
 
-	/* Device options, independant from channel groups. */
+	/* Device options, independent from channel groups. */
 	if (cg == NULL) {
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-							  hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+							  hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 			return SR_OK;
 		case SR_CONF_OUTPUT_CHANNEL_CONFIG:
 			if (devc->model->modelid <= LPS_303) {
@@ -769,11 +769,11 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
 		if ((ch_idx == 0) || (ch_idx == 1)) /* CH1, CH2 */
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				  hwcaps_ch12, ARRAY_SIZE(hwcaps_ch12), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				  hwcaps_ch12, ARRAY_SIZE(hwcaps_ch12), sizeof(uint32_t));
 		else /* Must be CH3 */
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				  hwcaps_ch3, ARRAY_SIZE(hwcaps_ch3), sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				  hwcaps_ch3, ARRAY_SIZE(hwcaps_ch3), sizeof(uint32_t));
 		break;
 	case SR_CONF_OUTPUT_VOLTAGE_MAX:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
diff --git a/src/hardware/norma-dmm/api.c b/src/hardware/norma-dmm/api.c
index 798b60e1..1eda0cf9 100644
--- a/src/hardware/norma-dmm/api.c
+++ b/src/hardware/norma-dmm/api.c
@@ -24,12 +24,12 @@
 
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -235,7 +235,7 @@ static int cleanup_siemens_b102x(void)
 	return std_dev_clear(&siemens_b102x_driver_info, NULL);
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -272,7 +272,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -280,12 +280,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/openbench-logic-sniffer/api.c b/src/hardware/openbench-logic-sniffer/api.c
index cd9d817e..ac69250c 100644
--- a/src/hardware/openbench-logic-sniffer/api.c
+++ b/src/hardware/openbench-logic-sniffer/api.c
@@ -22,12 +22,12 @@
 
 #define SERIALCOMM "115200/8n1"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -215,7 +215,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -226,7 +226,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 		return SR_ERR_ARG;
 
 	devc = sdi->priv;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		*data = g_variant_new_uint64(devc->cur_samplerate);
 		break;
@@ -254,7 +254,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -270,7 +270,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		tmp_u64 = g_variant_get_uint64(data);
 		if (tmp_u64 < samplerates[0] || tmp_u64 > samplerates[1])
@@ -351,7 +351,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -363,12 +363,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/pipistrello-ols/api.c b/src/hardware/pipistrello-ols/api.c
index 01d82a6f..89282179 100644
--- a/src/hardware/pipistrello-ols/api.c
+++ b/src/hardware/pipistrello-ols/api.c
@@ -19,7 +19,7 @@
 
 #include "protocol.h"
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -236,7 +236,7 @@ static int cleanup(void)
 }
 
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -247,7 +247,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 		return SR_ERR_ARG;
 
 	devc = sdi->priv;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		*data = g_variant_new_uint64(devc->cur_samplerate);
 		break;
@@ -278,7 +278,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -294,7 +294,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		tmp_u64 = g_variant_get_uint64(data);
 		if (tmp_u64 < samplerates[0] || tmp_u64 > samplerates[1])
@@ -375,7 +375,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -387,8 +387,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/rigol-ds/api.c b/src/hardware/rigol-ds/api.c
index 500362be..f11d233d 100644
--- a/src/hardware/rigol-ds/api.c
+++ b/src/hardware/rigol-ds/api.c
@@ -29,12 +29,12 @@
 #include "libsigrok-internal.h"
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_OSCILLOSCOPE,
 	SR_CONF_TIMEBASE,
 	SR_CONF_TRIGGER_SOURCE,
@@ -45,7 +45,7 @@ static const int32_t hwcaps[] = {
 	SR_CONF_SAMPLERATE,
 };
 
-static const int32_t analog_hwcaps[] = {
+static const uint32_t analog_hwcaps[] = {
 	SR_CONF_NUM_VDIV,
 	SR_CONF_VDIV,
 	SR_CONF_COUPLING,
@@ -489,7 +489,7 @@ static int digital_frame_size(const struct sr_dev_inst *sdi)
 	}
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -521,7 +521,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 		}
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_NUM_TIMEBASE:
 		*data = g_variant_new_int32(devc->model->series->num_horizontal_divs);
 		break;
@@ -609,7 +609,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -633,7 +633,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	}
 
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_FRAMES:
 		devc->limit_frames = g_variant_get_uint64(data);
 		break;
@@ -759,7 +759,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *tuple, *rational[2];
@@ -771,12 +771,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		devc = sdi->priv;
 
 	if (key == SR_CONF_SCAN_OPTIONS) {
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		return SR_OK;
 	} else if (key == SR_CONF_DEVICE_OPTIONS && cg == NULL) {
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-			hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+			hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		return SR_OK;
 	}
 
@@ -802,14 +802,14 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 			return SR_ERR_CHANNEL_GROUP;
 		}
 		if (cg == devc->digital_group) {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				NULL, 0, sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				NULL, 0, sizeof(uint32_t));
 			return SR_OK;
 		} else {
 			for (i = 0; i < devc->model->analog_channels; i++) {
 				if (cg == devc->analog_groups[i]) {
-					*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-						analog_hwcaps, ARRAY_SIZE(analog_hwcaps), sizeof(int32_t));
+					*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+						analog_hwcaps, ARRAY_SIZE(analog_hwcaps), sizeof(uint32_t));
 					return SR_OK;
 				}
 			}
diff --git a/src/hardware/saleae-logic16/api.c b/src/hardware/saleae-logic16/api.c
index 6bd539ca..f20eadcb 100644
--- a/src/hardware/saleae-logic16/api.c
+++ b/src/hardware/saleae-logic16/api.c
@@ -41,11 +41,11 @@
 SR_PRIV struct sr_dev_driver saleae_logic16_driver_info;
 static struct sr_dev_driver *di = &saleae_logic16_driver_info;
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_VOLTAGE_THRESHOLD,
@@ -436,7 +436,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -490,7 +490,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -533,7 +533,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	GVariant *gvar, *range[2];
@@ -547,12 +547,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	ret = SR_OK;
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/scpi-pps/api.c b/src/hardware/scpi-pps/api.c
index 2f4bdc93..aea3bd5e 100644
--- a/src/hardware/scpi-pps/api.c
+++ b/src/hardware/scpi-pps/api.c
@@ -25,7 +25,7 @@ static struct sr_dev_driver *di = &scpi_pps_driver_info;
 extern unsigned int num_pps_profiles;
 extern const struct scpi_pps pps_profiles[];
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
@@ -190,7 +190,7 @@ static int cleanup(void)
 	return SR_OK;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -313,7 +313,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct sr_channel *ch;
@@ -396,7 +396,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -409,8 +409,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	/* Always available, even without sdi. */
 	if (key == SR_CONF_SCAN_OPTIONS) {
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		return SR_OK;
 	}
 
@@ -423,9 +423,9 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		/* No channel group: global options. */
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 					devc->device->devopts, devc->device->num_devopts,
-					sizeof(int32_t));
+					sizeof(uint32_t));
 			break;
 		case SR_CONF_OUTPUT_CHANNEL_CONFIG:
 			/* Not used. */
@@ -460,9 +460,9 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 		switch (key) {
 		case SR_CONF_DEVICE_OPTIONS:
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
 					devc->device->devopts_cg, devc->device->num_devopts_cg,
-					sizeof(int32_t));
+					sizeof(uint32_t));
 			break;
 		case SR_CONF_OUTPUT_VOLTAGE_MAX:
 			ch_spec = &(devc->device->channels[ch->index]);
diff --git a/src/hardware/scpi-pps/profiles.c b/src/hardware/scpi-pps/profiles.c
index 34f4a6a3..925b6db8 100644
--- a/src/hardware/scpi-pps/profiles.c
+++ b/src/hardware/scpi-pps/profiles.c
@@ -39,16 +39,16 @@ const char *get_vendor(const char *raw_vendor)
 	return raw_vendor;
 }
 
-static const int32_t devopts_none[] = { };
+static const uint32_t devopts_none[] = { };
 
 /* Rigol DP800 series */
-static const int32_t rigol_dp800_devopts[] = {
+static const uint32_t rigol_dp800_devopts[] = {
 	SR_CONF_POWER_SUPPLY,
 	SR_CONF_CONTINUOUS,
 	SR_CONF_OVER_TEMPERATURE_PROTECTION,
 };
 
-static const int32_t rigol_dp800_devopts_cg[] = {
+static const uint32_t rigol_dp800_devopts_cg[] = {
 	SR_CONF_OUTPUT_REGULATION,
 	SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED,
 	SR_CONF_OVER_VOLTAGE_PROTECTION_ACTIVE,
@@ -108,7 +108,7 @@ struct scpi_command rigol_dp800_cmd[] = {
 };
 
 /* HP 663xx series */
-static const int32_t hp_6632b_devopts[] = {
+static const uint32_t hp_6632b_devopts[] = {
 	SR_CONF_POWER_SUPPLY,
 	SR_CONF_CONTINUOUS,
 	SR_CONF_OUTPUT_ENABLED,
diff --git a/src/hardware/scpi-pps/protocol.h b/src/hardware/scpi-pps/protocol.h
index d6695add..552d5030 100644
--- a/src/hardware/scpi-pps/protocol.h
+++ b/src/hardware/scpi-pps/protocol.h
@@ -71,9 +71,9 @@ struct scpi_pps {
 	char *vendor;
 	char *model;
 	uint64_t features;
-	const int32_t *devopts;
+	const uint32_t *devopts;
 	unsigned int num_devopts;
-	const int32_t *devopts_cg;
+	const uint32_t *devopts_cg;
 	unsigned int num_devopts_cg;
 	struct channel_spec *channels;
 	unsigned int num_channels;
diff --git a/src/hardware/serial-dmm/api.c b/src/hardware/serial-dmm/api.c
index a401dd65..d92b6fc1 100644
--- a/src/hardware/serial-dmm/api.c
+++ b/src/hardware/serial-dmm/api.c
@@ -29,12 +29,12 @@
 #include "libsigrok-internal.h"
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -465,7 +465,7 @@ static int cleanup(int dmm)
 	return dev_clear(dmm);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -480,7 +480,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_BUG;
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
 		devc->limit_samples = g_variant_get_uint64(data);
 		sr_dbg("Setting sample limit to %" PRIu64 ".",
@@ -498,7 +498,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -506,12 +506,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/sysclk-lwla/api.c b/src/hardware/sysclk-lwla/api.c
index a4346a01..d2aeb301 100644
--- a/src/hardware/sysclk-lwla/api.c
+++ b/src/hardware/sysclk-lwla/api.c
@@ -25,11 +25,11 @@
 #include <stdlib.h>
 #include <string.h>
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_EXTERNAL_CLOCK,
@@ -271,7 +271,7 @@ static int cleanup(void)
 	return dev_clear();
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		      const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -343,7 +343,7 @@ static int lookup_index(GVariant *value, const char *const *table, int len)
 	return -1;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		      const struct sr_channel_group *cg)
 {
 	uint64_t value;
@@ -445,7 +445,7 @@ static int config_commit(const struct sr_dev_inst *sdi)
 	return lwla_set_clock_config(sdi);
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		       const struct sr_channel_group *cg)
 {
 	GVariant *gvar;
@@ -456,12 +456,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, G_N_ELEMENTS(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, G_N_ELEMENTS(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, G_N_ELEMENTS(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, G_N_ELEMENTS(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		g_variant_builder_init(&gvb, G_VARIANT_TYPE("a{sv}"));
diff --git a/src/hardware/teleinfo/api.c b/src/hardware/teleinfo/api.c
index c4fd8467..48d77543 100644
--- a/src/hardware/teleinfo/api.c
+++ b/src/hardware/teleinfo/api.c
@@ -23,12 +23,12 @@
 #include "libsigrok-internal.h"
 #include "protocol.h"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_ENERGYMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -177,7 +177,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -208,7 +208,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -216,12 +216,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/testo/api.c b/src/hardware/testo/api.c
index 2b4c9634..c0604da6 100644
--- a/src/hardware/testo/api.c
+++ b/src/hardware/testo/api.c
@@ -26,11 +26,11 @@ SR_PRIV struct sr_dev_driver testo_driver_info;
 static struct sr_dev_driver *di = &testo_driver_info;
 static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data);
 
-static const int32_t scanopts[] = {
+static const uint32_t scanopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t devopts[] = {
+static const uint32_t devopts[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_MSEC,
 	SR_CONF_LIMIT_SAMPLES,
@@ -241,7 +241,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct sr_usb_dev_inst *usb;
@@ -264,7 +264,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -303,7 +303,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -311,12 +311,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				scanopts, ARRAY_SIZE(scanopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				scanopts, ARRAY_SIZE(scanopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				devopts, ARRAY_SIZE(devopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				devopts, ARRAY_SIZE(devopts), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/tondaj-sl-814/api.c b/src/hardware/tondaj-sl-814/api.c
index 7917c8d2..11885c72 100644
--- a/src/hardware/tondaj-sl-814/api.c
+++ b/src/hardware/tondaj-sl-814/api.c
@@ -26,12 +26,12 @@
 
 #define SERIALCOMM "9600/8e1"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 	SR_CONF_SERIALCOMM,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_SOUNDLEVELMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_CONTINUOUS,
@@ -128,7 +128,7 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -140,7 +140,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_SAMPLES:
 		devc->limit_samples = g_variant_get_uint64(data);
 		sr_dbg("Setting sample limit to %" PRIu64 ".",
@@ -153,7 +153,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -161,12 +161,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/uni-t-dmm/api.c b/src/hardware/uni-t-dmm/api.c
index f0fcc1fd..46158f32 100644
--- a/src/hardware/uni-t-dmm/api.c
+++ b/src/hardware/uni-t-dmm/api.c
@@ -26,11 +26,11 @@
 
 #define UNI_T_UT_D04_NEW "1a86.e008"
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_LIMIT_MSEC,
@@ -267,7 +267,7 @@ static int cleanup(int dmm)
 	return dev_clear(dmm);
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -276,7 +276,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
 		if (g_variant_get_uint64(data) == 0) {
 			sr_err("Time limit cannot be 0.");
@@ -302,7 +302,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -310,12 +310,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/uni-t-ut32x/api.c b/src/hardware/uni-t-ut32x/api.c
index 81024dc7..52f0c476 100644
--- a/src/hardware/uni-t-ut32x/api.c
+++ b/src/hardware/uni-t-ut32x/api.c
@@ -21,7 +21,7 @@
 
 #include <string.h>
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_THERMOMETER,
 	SR_CONF_LIMIT_SAMPLES,
 	SR_CONF_CONTINUOUS,
@@ -199,7 +199,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -224,7 +224,7 @@ static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -265,7 +265,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 
@@ -274,8 +274,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_DATA_SOURCE:
 		*data = g_variant_new_strv(data_sources, ARRAY_SIZE(data_sources));
diff --git a/src/hardware/victor-dmm/api.c b/src/hardware/victor-dmm/api.c
index 56c53e50..92a1ace8 100644
--- a/src/hardware/victor-dmm/api.c
+++ b/src/hardware/victor-dmm/api.c
@@ -35,11 +35,11 @@ SR_PRIV struct sr_dev_driver victor_dmm_driver_info;
 static struct sr_dev_driver *di = &victor_dmm_driver_info;
 static int dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data);
 
-static const int32_t hwopts[] = {
+static const uint32_t hwopts[] = {
 	SR_CONF_CONN,
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_MULTIMETER,
 	SR_CONF_LIMIT_MSEC,
 	SR_CONF_LIMIT_SAMPLES,
@@ -201,7 +201,7 @@ static int cleanup(void)
 	return ret;
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct sr_usb_dev_inst *usb;
@@ -209,7 +209,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_CONN:
 		if (!sdi || !sdi->conn)
 			return SR_ERR_ARG;
@@ -224,7 +224,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -243,7 +243,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	devc = sdi->priv;
 	ret = SR_OK;
-	switch (id) {
+	switch (key) {
 	case SR_CONF_LIMIT_MSEC:
 		devc->limit_msec = g_variant_get_uint64(data);
 		now = g_get_monotonic_time() / 1000;
@@ -263,7 +263,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -271,12 +271,12 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_SCAN_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwopts, ARRAY_SIZE(hwopts), sizeof(uint32_t));
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;
diff --git a/src/hardware/yokogawa-dlm/api.c b/src/hardware/yokogawa-dlm/api.c
index 070c6bd0..276ff0ff 100644
--- a/src/hardware/yokogawa-dlm/api.c
+++ b/src/hardware/yokogawa-dlm/api.c
@@ -189,7 +189,7 @@ static int check_channel_group(struct dev_context *devc,
 	return CG_INVALID;
 }
 
-static int config_get(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int ret, cg_type;
@@ -307,7 +307,7 @@ static GVariant *build_tuples(const uint64_t (*array)[][2], unsigned int n)
 	return g_variant_builder_end(&gvb);
 }
 
-static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int ret, cg_type;
@@ -461,7 +461,7 @@ static int config_set(int key, GVariant *data, const struct sr_dev_inst *sdi,
 	return ret;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	int cg_type;
@@ -482,14 +482,14 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 		break;
 	case SR_CONF_DEVICE_OPTIONS:
 		if (cg_type == CG_NONE) {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				model->hw_caps, model->num_hwcaps, sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				model->hw_caps, model->num_hwcaps, sizeof(uint32_t));
 		} else if (cg_type == CG_ANALOG) {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				model->analog_hwcaps, model->num_analog_hwcaps,	sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				model->analog_hwcaps, model->num_analog_hwcaps,	sizeof(uint32_t));
 		} else {
-			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				NULL, 0, sizeof(int32_t));
+			*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				NULL, 0, sizeof(uint32_t));
 		}
 		break;
 	case SR_CONF_COUPLING:
diff --git a/src/hardware/yokogawa-dlm/protocol.c b/src/hardware/yokogawa-dlm/protocol.c
index 8f95f187..5148c8d7 100644
--- a/src/hardware/yokogawa-dlm/protocol.c
+++ b/src/hardware/yokogawa-dlm/protocol.c
@@ -25,7 +25,7 @@
 
 #include "protocol.h"
 
-static const int32_t dlm_hwcaps[] = {
+static const uint32_t dlm_hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_OSCILLOSCOPE,
 	SR_CONF_TRIGGER_SLOPE,
@@ -35,7 +35,7 @@ static const int32_t dlm_hwcaps[] = {
 	SR_CONF_HORIZ_TRIGGERPOS,
 };
 
-static const int32_t dlm_analog_caps[] = {
+static const uint32_t dlm_analog_caps[] = {
 	SR_CONF_VDIV,
 	SR_CONF_COUPLING,
 	SR_CONF_NUM_VDIV,
diff --git a/src/hardware/yokogawa-dlm/protocol.h b/src/hardware/yokogawa-dlm/protocol.h
index 0950267a..523403d5 100644
--- a/src/hardware/yokogawa-dlm/protocol.h
+++ b/src/hardware/yokogawa-dlm/protocol.h
@@ -57,10 +57,10 @@ struct scope_config {
 	const char *(*analog_names)[];
 	const char *(*digital_names)[];
 
-	const int32_t (*hw_caps)[];
+	const uint32_t (*hw_caps)[];
 	const uint8_t num_hwcaps;
 
-	const int32_t (*analog_hwcaps)[];
+	const uint32_t (*analog_hwcaps)[];
 	const uint8_t num_analog_hwcaps;
 
 	const char *(*coupling_options)[];
diff --git a/src/hardware/zeroplus-logic-cube/api.c b/src/hardware/zeroplus-logic-cube/api.c
index a49f0748..3a0e4d8c 100644
--- a/src/hardware/zeroplus-logic-cube/api.c
+++ b/src/hardware/zeroplus-logic-cube/api.c
@@ -52,7 +52,7 @@ static const struct zp_model zeroplus_models[] = {
 	{ 0, 0, 0, 0, 0, 0 }
 };
 
-static const int32_t hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_LOGIC_ANALYZER,
 	SR_CONF_SAMPLERATE,
 	SR_CONF_TRIGGER_MATCH,
@@ -382,14 +382,14 @@ static int cleanup(void)
 	return std_dev_clear(di, NULL);
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
 
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		if (sdi) {
 			devc = sdi->priv;
@@ -423,7 +423,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -439,7 +439,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 		return SR_ERR_ARG;
 	}
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		return zp_set_samplerate(devc, g_variant_get_uint64(data));
 	case SR_CONF_LIMIT_SAMPLES:
@@ -456,7 +456,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct dev_context *devc;
@@ -469,8 +469,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	case SR_CONF_SAMPLERATE:
 		devc = sdi->priv;
diff --git a/src/hwdriver.c b/src/hwdriver.c
index bf0ce04d..e36990a2 100644
--- a/src/hwdriver.c
+++ b/src/hwdriver.c
@@ -166,7 +166,7 @@ SR_PRIV const GVariantType *sr_variant_type_get(int datatype)
 	}
 }
 
-SR_PRIV int sr_variant_type_check(int key, GVariant *value)
+SR_PRIV int sr_variant_type_check(uint32_t key, GVariant *value)
 {
 	const struct sr_config_info *info;
 	const GVariantType *type, *expected;
@@ -312,7 +312,7 @@ SR_PRIV void sr_hw_cleanup_all(void)
  *  A floating reference can be passed in for data.
  *  @private
  */
-SR_PRIV struct sr_config *sr_config_new(int key, GVariant *data)
+SR_PRIV struct sr_config *sr_config_new(uint32_t key, GVariant *data)
 {
 	struct sr_config *src;
 
@@ -367,7 +367,7 @@ SR_PRIV void sr_config_free(struct sr_config *src)
 SR_API int sr_config_get(const struct sr_dev_driver *driver,
 		const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant **data)
+		uint32_t key, GVariant **data)
 {
 	int ret;
 
@@ -407,7 +407,7 @@ SR_API int sr_config_get(const struct sr_dev_driver *driver,
  */
 SR_API int sr_config_set(const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant *data)
+		uint32_t key, GVariant *data)
 {
 	int ret;
 
@@ -474,7 +474,7 @@ SR_API int sr_config_commit(const struct sr_dev_inst *sdi)
 SR_API int sr_config_list(const struct sr_dev_driver *driver,
 		const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg,
-		int key, GVariant **data)
+		uint32_t key, GVariant **data)
 {
 	int ret;
 
@@ -498,7 +498,7 @@ SR_API int sr_config_list(const struct sr_dev_driver *driver,
  *
  * @since 0.2.0
  */
-SR_API const struct sr_config_info *sr_config_info_get(int key)
+SR_API const struct sr_config_info *sr_config_info_get(uint32_t key)
 {
 	int i;
 
diff --git a/src/libsigrok-internal.h b/src/libsigrok-internal.h
index 4bd7a7da..1fc049e4 100644
--- a/src/libsigrok-internal.h
+++ b/src/libsigrok-internal.h
@@ -517,9 +517,9 @@ SR_PRIV void sr_usbtmc_dev_inst_free(struct sr_usbtmc_dev_inst *usbtmc);
 /*--- hwdriver.c ------------------------------------------------------------*/
 
 SR_PRIV const GVariantType *sr_variant_type_get(int datatype);
-SR_PRIV int sr_variant_type_check(int key, GVariant *data);
+SR_PRIV int sr_variant_type_check(uint32_t key, GVariant *data);
 SR_PRIV void sr_hw_cleanup_all(void);
-SR_PRIV struct sr_config *sr_config_new(int key, GVariant *data);
+SR_PRIV struct sr_config *sr_config_new(uint32_t key, GVariant *data);
 SR_PRIV void sr_config_free(struct sr_config *src);
 SR_PRIV int sr_source_remove(int fd);
 SR_PRIV int sr_source_remove_pollfd(GPollFD *pollfd);
diff --git a/src/session_driver.c b/src/session_driver.c
index 9120ea14..6a320aa5 100644
--- a/src/session_driver.c
+++ b/src/session_driver.c
@@ -49,7 +49,7 @@ struct session_vdev {
 	gboolean finished;
 };
 
-static const int hwcaps[] = {
+static const uint32_t hwcaps[] = {
 	SR_CONF_CAPTUREFILE,
 	SR_CONF_CAPTURE_UNITSIZE,
 	SR_CONF_SAMPLERATE,
@@ -209,14 +209,14 @@ static int dev_close(struct sr_dev_inst *sdi)
 	return SR_OK;
 }
 
-static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_get(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct session_vdev *vdev;
 
 	(void)cg;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		if (sdi) {
 			vdev = sdi->priv;
@@ -231,7 +231,7 @@ static int config_get(int id, GVariant **data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
+static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	struct session_vdev *vdev;
@@ -240,7 +240,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 
 	vdev = sdi->priv;
 
-	switch (id) {
+	switch (key) {
 	case SR_CONF_SAMPLERATE:
 		vdev->samplerate = g_variant_get_uint64(data);
 		sr_info("Setting samplerate to %" PRIu64 ".", vdev->samplerate);
@@ -268,7 +268,7 @@ static int config_set(int id, GVariant *data, const struct sr_dev_inst *sdi,
 	return SR_OK;
 }
 
-static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
+static int config_list(uint32_t key, GVariant **data, const struct sr_dev_inst *sdi,
 		const struct sr_channel_group *cg)
 {
 	(void)sdi;
@@ -276,8 +276,8 @@ static int config_list(int key, GVariant **data, const struct sr_dev_inst *sdi,
 
 	switch (key) {
 	case SR_CONF_DEVICE_OPTIONS:
-		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
-				hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
+		*data = g_variant_new_fixed_array(G_VARIANT_TYPE_UINT32,
+				hwcaps, ARRAY_SIZE(hwcaps), sizeof(uint32_t));
 		break;
 	default:
 		return SR_ERR_NA;