firewire: core: add KUnit test skeleton for config ROM parser and generator

In IEEE 1394, all devices on the bus are required to provide structured
data in response to requests to a specific range of their address space.
This structured data is called configuration ROM and is defined in
IEEE 1212.

The core function of this subsystem contains the generator and parser for
the configuration ROM. The generator constructs the configuration ROM for
the local host node, while the parser interprets the configuration ROM of
detected nodes.

Both the generator and parser are fundamental to identifying the node
capabilities. Add KUnit test skeletons for testing their implementations.

Link: https://lore.kernel.org/r/20260901134534.2386577-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

drivers/firewire/.kunitconfig

@@ -7,3 +7,4 @@ CONFIG_FIREWIRE_KUNIT_PACKET_SERDES_TEST=y
 CONFIG_FIREWIRE_KUNIT_SELF_ID_SEQUENCE_HELPER_TEST=y
 CONFIG_FIREWIRE_KUNIT_OHCI_SERDES_TEST=y
 CONFIG_FIREWIRE_KUNIT_NODE_TREE_TEST=y
+CONFIG_FIREWIRE_KUNIT_CONFIG_ROM_PARSER_AND_GENERATOR_TEST=y

drivers/firewire/Kconfig

@@ -96,6 +96,22 @@ config FIREWIRE_KUNIT_NODE_TREE_TEST
 	  For more information on KUnit and unit tests in general, refer
 	  to the KUnit documentation in Documentation/dev-tools/kunit/.
 
+config FIREWIRE_KUNIT_CONFIG_ROM_PARSER_AND_GENERATOR_TEST
+	tristate "KUnit tests for config ROM parser and generator" if !KUNIT_ALL_TESTS
+	depends on FIREWIRE && KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  This builds the KUnit tests to check parser and generator for
+	  configuration ROM content defined in IEEE 1212.
+
+	  KUnit tests run during boot and output the results to the debug
+	  log in TAP format (https://testanything.org/). Only useful for
+	  kernel devs running KUnit test harness and are not for inclusion
+	  into a production build.
+
+	  For more information on KUnit and unit tests in general, refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
 config FIREWIRE_OHCI
 	tristate "OHCI-1394 controllers"
 	depends on PCI && FIREWIRE

drivers/firewire/config-rom-generator-test.c

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// config-rom-generator-test.c - An application of Kunit to test configuration ROM generator.
+//
+// Copyright (c) 2026 Takashi Sakamoto
+//
+// This file can not be built independently since it is intentionally included in core-card.c.
+
+#include <kunit/test.h>
+
+static struct kunit_case config_rom_generator_test_cases[] = {
+	{}
+};
+
+static struct kunit_suite config_rom_generator_test_suite = {
+	.name = "firewire-config-rom-generator",
+	.test_cases = config_rom_generator_test_cases,
+};
+kunit_test_suite(config_rom_generator_test_suite);

drivers/firewire/config-rom-parser-test.c

@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// config-rom-parser-test.c - An application of Kunit to test configuration ROM parser.
+//
+// Copyright (c) 2026 Takashi Sakamoto
+//
+// This file can not be built independently since it is intentionally included in core-device.c.
+
+#include <kunit/test.h>
+
+static struct kunit_case config_rom_parser_test_cases[] = {
+	{}
+};
+
+static struct kunit_suite config_rom_parser_test_suite = {
+	.name = "firewire-config-rom-parser",
+	.test_cases = config_rom_parser_test_cases,
+};
+kunit_test_suite(config_rom_parser_test_suite);

drivers/firewire/core-card.c

@@ -851,3 +851,7 @@ int fw_card_read_cycle_time(struct fw_card *card, u32 *cycle_time)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fw_card_read_cycle_time);
+
+#ifdef CONFIG_FIREWIRE_KUNIT_CONFIG_ROM_PARSER_AND_GENERATOR_TEST
+#include "config-rom-generator-test.c"
+#endif

drivers/firewire/core-device.c

@@ -1442,3 +1442,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 #ifdef CONFIG_FIREWIRE_KUNIT_DEVICE_ATTRIBUTE_TEST
 #include "device-attribute-test.c"
 #endif
+
+#ifdef CONFIG_FIREWIRE_KUNIT_CONFIG_ROM_PARSER_AND_GENERATOR_TEST
+#include "config-rom-parser-test.c"
+#endif