ACPI: tables: Add custom DSDT file as makefile prerequisite

[ Upstream commit d1059c1b1146870c52f3dac12cb7b6cbf39ed27f ]

A custom DSDT file is mostly used during development or debugging,
and in that case it is quite likely to want to rebuild the kernel
after changing ONLY the content of the DSDT.

This patch adds the custom DSDT as a prerequisite to tables.o
to ensure a rebuild if the DSDT file is updated. Make will merge
the prerequisites from multiple rules for the same target.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 4c5678cfa9c49cf5c7429e9c48a1c32b99d08fde..c466d7bc861aebeb54b9c084885a6f2d2c7d3abe 100644 (file)
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -7,6 +7,11 @@ ccflags-$(CONFIG_ACPI_DEBUG)   += -DACPI_DEBUG_OUTPUT
 #
 # ACPI Boot-Time Table Parsing
 #
+ifeq ($(CONFIG_ACPI_CUSTOM_DSDT),y)
+tables.o: $(src)/../../include/$(subst $\",,$(CONFIG_ACPI_CUSTOM_DSDT_FILE)) ;
+
+endif
+
 obj-$(CONFIG_ACPI)             += tables.o
 obj-$(CONFIG_X86)              += blacklist.o