[ Upstream commit b68c1c65dec5fb5186ebd33ce52059b4c6db8500 ]
Currently the gpio selftests fail to build if the source tree is read
only:
make -j 160 -C tools/testing/selftests TARGETS=gpio
make[1]: Entering directory '/linux/tools/testing/selftests/gpio'
make OUTPUT=/linux/tools/gpio/ -C /linux/tools/gpio
make[2]: Entering directory '/linux/tools/gpio'
mkdir -p /linux/tools/gpio/include/linux 2>&1 || true
ln -sf /linux/tools/gpio/../../include/uapi/linux/gpio.h /linux/tools/gpio/include/linux/gpio.h
ln: failed to create symbolic link '/linux/tools/gpio/include/linux/gpio.h': Read-only file system
This happens because we ask make to build ../../../gpio (tools/gpio)
without pointing OUTPUT away from the source directory.
To fix it we create a subdirectory of the existing OUTPUT directory,
called tools-gpio, and tell tools/gpio to build in there.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
eeb3f0b0c3