diff --git a/lib/libx52io/Makefile.am b/lib/libx52io/Makefile.am
index 748017c..2069f0c 100644
--- a/lib/libx52io/Makefile.am
+++ b/lib/libx52io/Makefile.am
@@ -28,5 +28,15 @@ x52include_HEADERS = libx52io.h
 # pkg-config files
 # pkgconfig_DATA = libx52io.pc
 
+if HAVE_CMOCKA
+LOG_DRIVER = env AM_TAP_AWK='$(AWK)' $(SHELL) $(top_srcdir)/tap-driver.sh
+TESTS = test-axis
+check_PROGRAMS = $(TESTS)
+
+test_axis_SOURCES = test_axis.c $(libx52io_la_SOURCES)
+test_axis_CFLAGS = $(libx52io_la_CFLAGS)
+test_axis_LDFLAGS = @CMOCKA_LIBS@ @HIDAPI_LIBS@ $(WARN_LDFLAGS)
+endif
+
 # Extra files that need to be in the distribution
 EXTRA_DIST = libx52io.h io_common.h
diff --git a/lib/libx52io/io_core.c b/lib/libx52io/io_core.c
index 8d28f37..de9efa9 100644
--- a/lib/libx52io/io_core.c
+++ b/lib/libx52io/io_core.c
@@ -52,8 +52,8 @@ int libx52io_close(libx52io_context *ctx)
 
     if (ctx->handle != NULL) {
         hid_close(ctx->handle);
-        memset(ctx, 0, sizeof(*ctx));
     }
+    memset(ctx, 0, sizeof(*ctx));
 
     return LIBX52IO_SUCCESS;
 }
diff --git a/lib/libx52io/test_axis.c b/lib/libx52io/test_axis.c
new file mode 100644
index 0000000..3f0b727
--- /dev/null
+++ b/lib/libx52io/test_axis.c
@@ -0,0 +1,140 @@
+/*
+ * Saitek X52 IO driver - Axis test suite
+ *
+ * Copyright (C) 2012-2020 Nirenjan Krishnan (nirenjan@nirenjan.org)
+ *
+ * SPDX-License-Identifier: GPL-2.0-only WITH Classpath-exception-2.0
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <setjmp.h>
+#include <cmocka.h>
+
+#include "io_common.h"
+#include "usb-ids.h"
+
+static int group_setup(void **state)
+{
+    libx52io_context *ctx;
+    int rc;
+
+    rc = libx52io_init(&ctx);
+    if (rc != LIBX52IO_SUCCESS) {
+        return rc;
+    }
+
+    *state = ctx;
+    return 0;
+}
+
+static int test_setup(void **state)
+{
+    libx52io_context *ctx = *state;
+
+    /* Create a dummy handle so that the test cases don't abort early */
+    ctx->handle = (void *)(uintptr_t)(-1);
+
+    return 0;
+}
+
+static int test_teardown(void **state)
+{
+    libx52io_context *ctx = *state;
+
+    ctx->handle = NULL;
+    libx52io_close(ctx);
+    return 0;
+}
+
+static int group_teardown(void **state)
+{
+    libx52io_context *ctx = *state;
+
+    ctx->handle = NULL;
+    libx52io_exit(ctx);
+    return 0;
+}
+
+/* List of test cases - list the axis and the corresponding maximum for that axis */
+#define TEST_CASES \
+    TEST_X52(X, 2047) \
+    TEST_X52(Y, 2047) \
+    TEST_X52(RZ, 1023) \
+    TEST_X52(Z, 255) \
+    TEST_X52(RX, 255) \
+    TEST_X52(RY, 255) \
+    TEST_X52(SLIDER, 255) \
+    TEST_X52(THUMBX, 15) \
+    TEST_X52(THUMBY, 15) \
+    TEST_PRO(X, 1023) \
+    TEST_PRO(Y, 1023) \
+    TEST_PRO(RZ, 1023) \
+    TEST_PRO(Z, 255) \
+    TEST_PRO(RX, 255) \
+    TEST_PRO(RY, 255) \
+    TEST_PRO(SLIDER, 255) \
+    TEST_PRO(THUMBX, 15) \
+    TEST_PRO(THUMBY, 15)
+
+#define TEST_X52(axis, max) TEST(_1, axis, max) TEST(_2, axis, max)
+#define TEST_PRO(axis, max) TEST(PRO, axis, max)
+
+#define TEST(prodid, axis, maxval) \
+    static void axis ## _ ## prodid (void **state) \
+    { \
+        libx52io_context *ctx = *state; \
+        int rc; \
+        int32_t min, max; \
+        ctx->pid = X52_PROD_X52 ## prodid; \
+        _x52io_set_axis_range(ctx); \
+        rc = libx52io_get_axis_range(ctx, LIBX52IO_AXIS_ ## axis, &min, &max); \
+        assert_int_equal(rc, LIBX52IO_SUCCESS); \
+        assert_int_equal(min, 0); \
+        assert_int_equal(max, maxval); \
+    }
+
+TEST_CASES
+#undef TEST
+
+static void test_error_case(void **state)
+{
+    libx52io_context *ctx = *state;
+    int rc;
+    int32_t min, max;
+
+    rc = libx52io_get_axis_range(NULL, 0, NULL, NULL);
+    assert_int_equal(rc, LIBX52IO_ERROR_INVALID);
+
+    rc = libx52io_get_axis_range(ctx, 0, NULL, NULL);
+    assert_int_equal(rc, LIBX52IO_ERROR_INVALID);
+
+    rc = libx52io_get_axis_range(ctx, 0, &min, NULL);
+    assert_int_equal(rc, LIBX52IO_ERROR_INVALID);
+
+    rc = libx52io_get_axis_range(ctx, -1, &min, &max);
+    assert_int_equal(rc, LIBX52IO_ERROR_INVALID);
+
+    rc = libx52io_get_axis_range(ctx, LIBX52IO_AXIS_MAX, &min, &max);
+    assert_int_equal(rc, LIBX52IO_ERROR_INVALID);
+
+    ctx->handle = NULL;
+    rc = libx52io_get_axis_range(ctx, LIBX52IO_AXIS_X, &min, &max);
+    assert_int_equal(rc, LIBX52IO_ERROR_NO_DEVICE);
+}
+
+#define TEST(prodid, axis, maxval) cmocka_unit_test_setup_teardown(axis ## _ ## prodid, test_setup, test_teardown),
+
+const struct CMUnitTest tests[] = {
+    cmocka_unit_test_setup_teardown(test_error_case, test_setup, test_teardown),
+    TEST_CASES
+};
+#undef TEST
+
+int main(void)
+{
+    cmocka_set_message_output(CM_OUTPUT_TAP);
+    cmocka_run_group_tests(tests, group_setup, group_teardown);
+    return 0;
+}
+