hp-3478a: Fix switching from 4-wire to 2-wire measurement.

[libsigrok.git] / src / hardware / hp-3478a / api.c

diff --git a/src/hardware/hp-3478a/api.c b/src/hardware/hp-3478a/api.c
index f9419a6e09ced36fb7625a24990b2a50ae4387e4..0c461bb1740bebd4c4c4f1e41b892cfac1248057 100644 (file)
--- a/src/hardware/hp-3478a/api.c
+++ b/src/hardware/hp-3478a/api.c
@@ -1,7 +1,7 @@
 /*
  * This file is part of the libsigrok project.
  *
- * Copyright (C) 2017 Frank Stettner <frank-stettner@gmx.net>
+ * Copyright (C) 2017-2021 Frank Stettner <frank-stettner@gmx.net>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -129,6 +129,14 @@ static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi)
        struct sr_dev_inst *sdi;
        struct dev_context *devc;
 
+       /*
+        * The device cannot get identified by means of SCPI queries.
+        * Neither shall non-SCPI requests get emitted before reliable
+        * identification of the device. Assume that we only get here
+        * when user specs led us to believe it's safe to communicate
+        * to the expected kind of device.
+        */
+
        sdi = g_malloc0(sizeof(struct sr_dev_inst));
        sdi->vendor = g_strdup("Hewlett-Packard");
        sdi->model = g_strdup("3478A");
@@ -152,6 +160,14 @@ static struct sr_dev_inst *probe_device(struct sr_scpi_dev_inst *scpi)
 
 static GSList *scan(struct sr_dev_driver *di, GSList *options)
 {
+       const char *conn;
+
+       /* Only scan for a device when conn= was specified. */
+       conn = NULL;
+       (void)sr_serial_extract_options(options, &conn, NULL);
+       if (!conn)
+               return NULL;
+
        return sr_scpi_scan(di->context, options, probe_device);
 }
 
@@ -187,7 +203,7 @@ static int config_get(uint32_t key, GVariant **data,
                if (ret != SR_OK)
                        return ret;
                arr[0] = g_variant_new_uint32(devc->measurement_mq);
-               arr[1] = g_variant_new_uint64(devc->measurement_mq_flags);
+               arr[1] = g_variant_new_uint64(devc->measurement_mq_flag);
                *data = g_variant_new_tuple(arr, 2);
                break;
        case SR_CONF_RANGE:
@@ -197,7 +213,7 @@ static int config_get(uint32_t key, GVariant **data,
                range_str = "Auto";
                for (i = 0; i < ARRAY_SIZE(rangeopts); i++) {
                        if (rangeopts[i].mq == devc->measurement_mq &&
-                                       rangeopts[i].mqflag == devc->measurement_mq_flags &&
+                                       rangeopts[i].mqflag == devc->measurement_mq_flag &&
                                        rangeopts[i].range_exp == devc->range_exp) {
                                range_str = rangeopts[i].range_str;
                                break;
@@ -249,7 +265,7 @@ static int config_set(uint32_t key, GVariant *data,
                range_str = g_variant_get_string(data, NULL);
                for (i = 0; i < ARRAY_SIZE(rangeopts); i++) {
                        if (rangeopts[i].mq == devc->measurement_mq &&
-                                       rangeopts[i].mqflag == devc->measurement_mq_flags &&
+                                       rangeopts[i].mqflag == devc->measurement_mq_flag &&
                                        g_strcmp0(rangeopts[i].range_str, range_str) == 0) {
                                return hp_3478a_set_range(sdi, rangeopts[i].range_exp);
                        }
@@ -305,7 +321,7 @@ static int config_list(uint32_t key, GVariant **data,
                g_variant_builder_init(&gvb, G_VARIANT_TYPE_ARRAY);
                for (i = 0; i < ARRAY_SIZE(rangeopts); i++) {
                        if (rangeopts[i].mq == devc->measurement_mq &&
-                                       rangeopts[i].mqflag == devc->measurement_mq_flags) {
+                                       rangeopts[i].mqflag == devc->measurement_mq_flag) {
                                g_variant_builder_add(&gvb, "s", rangeopts[i].range_str);
                        }
                }