regmap: REGMAP_KUNIT should not select REGMAP

Enabling a (modular) test should not silently enable additional kernel
functionality, as that may increase the attack vector of a product.

Fix this by:
  1. making REGMAP visible if CONFIG_KUNIT_ALL_TESTS is enabled,
  2. making REGMAP_KUNIT depend on REGMAP instead of selecting it.

After this, one can safely enable CONFIG_KUNIT_ALL_TESTS=m to build
modules for all appropriate tests for ones system, without pulling in
extra unwanted functionality, while still allowing a tester to manually
enable REGMAP and its test suite on a system where REGMAP is not enabled
by default.

Fixes: 2238959b6ad27040 ("regmap: Add some basic kunit tests")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org
Link: https://lore.kernel.org/r/b0a5dbb17c1d5ea482e052e585ae83bb69c48806.1682516005.git.geert@linux-m68k.org
Signed-off-by: Mark Brown <broonie@kernel.org

diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig
index 33a8366e22a584a5681b9434cfac240e238d750c..0db2021f7477f2abd40ee69ff23dd759dbc6a1a7 100644 (file)
--- a/drivers/base/regmap/Kconfig
+++ b/drivers/base/regmap/Kconfig
@@ -4,16 +4,23 @@
 # subsystems should select the appropriate symbols.
 
 config REGMAP
+       bool "Register Map support" if KUNIT_ALL_TESTS
        default y if (REGMAP_I2C || REGMAP_SPI || REGMAP_SPMI || REGMAP_W1 || REGMAP_AC97 || REGMAP_MMIO || REGMAP_IRQ || REGMAP_SOUNDWIRE || REGMAP_SOUNDWIRE_MBQ || REGMAP_SCCB || REGMAP_I3C || REGMAP_SPI_AVMM || REGMAP_MDIO || REGMAP_FSI)
        select IRQ_DOMAIN if REGMAP_IRQ
        select MDIO_BUS if REGMAP_MDIO
-       bool
+       help
+         Enable support for the Register Map (regmap) access API.
+
+         Usually, this option is automatically selected when needed.
+         However, you may want to enable it manually for running the regmap
+         KUnit tests.
+
+         If unsure, say N.
 
 config REGMAP_KUNIT
        tristate "KUnit tests for regmap"
-       depends on KUNIT
+       depends on KUNIT && REGMAP
        default KUNIT_ALL_TESTS
-       select REGMAP
        select REGMAP_RAM
 
 config REGMAP_AC97