From 097ff01fb98a6f4ad03eed8cf639a5cc90fb6619 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sat, 22 Jan 2022 05:07:26 -0700 Subject: kconfig: Add support for conditional values At present if an optional Kconfig value needs to be used it must be bracketed by #ifdef. For example, with this Kconfig setup: config WIBBLE bool "Support wibbles, the world needs more wibbles" config WIBBLE_ADDR hex "Address of the wibble" depends on WIBBLE then the following code must be used: #ifdef CONFIG_WIBBLE static void handle_wibble(void) { int val = CONFIG_WIBBLE_ADDR; ... } #endif static void init_machine() { ... #ifdef CONFIG_WIBBLE handle_wibble(); #endif } Add a new IF_ENABLED_INT() to help with this. So now it is possible to write, without #ifdefs: static void handle_wibble(void) { int val = IF_ENABLED_INT(CONFIG_WIBBLE, CONFIG_WIBBLE_ADDR); ... } static void init_machine() { ... if (IS_ENABLED(CONFIG_WIBBLE)) handle_wibble(); } The value will be CONFIG_WIBBLE_ADDR if CONFIG_WIBBLE is defined and will produce a build error if not.. This allows us to reduce the use of #ifdef in the code, ensuring that the compiler still checks the code even if it is not ultimately used for a particular build. Add a CONFIG_IF_ENABLED_INT() version as well. If an attempt is made to use a value that does not exist (i.e. when the conditional is not enabled), an error about a non-existing function is generated, e.g.: common/bloblist.c:447: undefined reference to `invalid_use_of_IF_ENABLED_INT' Signed-off-by: Simon Glass --- scripts/Makefile.autoconf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.autoconf b/scripts/Makefile.autoconf index 5ed9abc8e14..0b3ffa08bfa 100644 --- a/scripts/Makefile.autoconf +++ b/scripts/Makefile.autoconf @@ -68,7 +68,7 @@ quiet_cmd_u_boot_cfg = CFG $@ cmd_u_boot_cfg = \ $(CPP) $(c_flags) $2 -DDO_DEPS_ONLY -dM $(srctree)/include/common.h > $@.tmp && { \ grep 'define CONFIG_' $@.tmp | \ - sed '/define CONFIG_IS_ENABLED(/d;/define CONFIG_VAL(/d;' > $@; \ + sed '/define CONFIG_IS_ENABLED(/d;/define CONFIG_IF_ENABLED_INT(/d;/define CONFIG_VAL(/d;' > $@; \ rm $@.tmp; \ } || { \ rm $@.tmp; false; \ -- cgit v1.2.3