sound/hda/core/ext/Makefile - kernel/common - Git at Google

 # SPDX-License-Identifier: GPL-2.0-only
 snd-hda-ext-core-y := bus.o controller.o stream.o

 obj-$(CONFIG_SND_HDA_EXT_CORE) += snd-hda-ext-core.o
	# SPDX-License-Identifier: GPL-2.0-only
	snd-hda-ext-core-y := bus.o controller.o stream.o

	obj-$(CONFIG_SND_HDA_EXT_CORE) += snd-hda-ext-core.o