mvm: core: Add bus control groundwork

Signed-off-by: Chloe M. <chloe@mirocom.org>

mvm/core/bus_ctl.c

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2026 Mirocom Laboratories and MSP engineers.
+ * All Rights Reserved.
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <errno.h>
+#include "mvm/bus.h"
+
+int
+bus_ctl_init(struct mvm_bus_ctl *busctl)
+{
+    if (busctl == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    busctl->head = NULL;
+    busctl->tail = NULL;
+    busctl->dev_count = 0;
+    return 0;
+}
+
+int
+bus_dev_alloc(mvm_devtype_t type, void *data, struct mvm_bus_dev **res)
+{
+    struct mvm_bus_dev *dev;
+
+    if (type == BUS_DEV_NONE || data == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (res == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if ((dev = malloc(sizeof(*dev))) == NULL) {
+        errno = ENOMEM;
+        return -1;
+    }
+
+    dev->type = type;
+    dev->data = data;
+    dev->next = NULL;
+    *res = dev;
+    return 0;
+}
+
+void
+bus_dev_free(struct mvm_bus_dev *dev)
+{
+    if (dev == NULL) {
+        return;
+    }
+
+    free(dev);
+}
+
+int
+bus_ctl_append(struct mvm_bus_ctl *busctl, struct mvm_bus_dev *dev)
+{
+    if (busctl == NULL || dev == NULL) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if (busctl->head == NULL || busctl->tail == NULL) {
+        busctl->head = dev;
+        busctl->tail = dev;
+    } else {
+        busctl->tail->next = dev;
+        busctl->tail = dev;
+    }
+
+    ++busctl->dev_count;
+    return 0;
+}
+
+void
+bus_ctl_free(struct mvm_bus_ctl *busctl)
+{
+    struct mvm_bus_dev *dev, *tmp;
+
+    if (busctl == NULL) {
+        return;
+    }
+
+    if ((dev = busctl->head) == NULL) {
+        return;
+    }
+
+    while (dev != NULL) {
+        tmp = dev;
+        bus_dev_free(tmp);
+        dev = dev->next;
+    }
+
+    busctl->head = NULL;
+    busctl->tail = NULL;
+}