scpi-pps: don't break SCPI devices when scanning for HP-IB devices

[libsigrok.git] / src / hardware / hp-3457a / api.c

diff --git a/src/hardware/hp-3457a/api.c b/src/hardware/hp-3457a/api.c
index 599cad74279d06466ca73a55b60b8c820b0bc160..f828cfd817f3743c7c764561c8ac8c5737285cff 100644 (file)
--- a/src/hardware/hp-3457a/api.c
+++ b/src/hardware/hp-3457a/api.c
@@ -138,13 +138,15 @@ static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi)
        if ((ret != SR_OK) || !response)
                return NULL;
 
-       if (strcmp(response, "HP3457A"))
+       if (strcmp(response, "HP3457A") != 0) {
+               g_free(response);
                return NULL;
+       }
 
        g_free(response);
 
-       devc = g_malloc0(sizeof(struct dev_context));
-       sdi = g_malloc0(sizeof(struct sr_dev_inst));
+       devc = g_malloc0(sizeof(*devc));
+       sdi = g_malloc0(sizeof(*sdi));
        sdi->vendor = g_strdup("Hewlett-Packard");
        sdi->model = g_strdup("3457A");
        sdi->version = get_revision(scpi);
@@ -245,7 +247,6 @@ static int config_get(uint32_t key, GVariant **data,
 static int config_set(uint32_t key, GVariant *data,
        const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
 {
-       int ret;
        enum sr_mq mq;
        enum sr_mqflag mq_flags;
        struct dev_context *devc;
@@ -255,7 +256,6 @@ static int config_set(uint32_t key, GVariant *data,
 
        devc = sdi->priv;
 
-       ret = SR_OK;
        switch (key) {
        case SR_CONF_LIMIT_SAMPLES:
                devc->limit_samples = g_variant_get_uint64(data);
@@ -265,17 +265,15 @@ static int config_set(uint32_t key, GVariant *data,
                mq = g_variant_get_uint32(tuple_child);
                tuple_child = g_variant_get_child_value(data, 1);
                mq_flags = g_variant_get_uint64(tuple_child);
-               ret = hp_3457a_set_mq(sdi, mq, mq_flags);
                g_variant_unref(tuple_child);
-               break;
+               return hp_3457a_set_mq(sdi, mq, mq_flags);
        case SR_CONF_ADC_POWERLINE_CYCLES:
-               ret = hp_3457a_set_nplc(sdi, g_variant_get_double(data));
-               break;
+               return hp_3457a_set_nplc(sdi, g_variant_get_double(data));
        default:
-               ret = SR_ERR_NA;
+               return SR_ERR_NA;
        }
 
-       return ret;
+       return SR_OK;
 }
 
 static int config_list(uint32_t key, GVariant **data,
@@ -363,8 +361,13 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
                return SR_ERR_ARG;
        }
 
-       devc->current_channel = devc->active_channels->data;
        devc->num_active_channels = g_slist_length(devc->active_channels);
+       if (!devc->num_active_channels) {
+               sr_err("Need at least one active channel!");
+               g_slist_free(devc->active_channels);
+               return SR_ERR_ARG;
+       }
+       devc->current_channel = devc->active_channels->data;
 
        hp_3457a_select_input(sdi, front_selected ? CONN_FRONT : CONN_REAR);