From fa72470a4ec5522fe92986bb53b22167d35d0913 Mon Sep 17 00:00:00 2001 From: Tom Rini Date: Tue, 1 Apr 2025 16:55:25 -0600 Subject: [PATCH] doc/develop/codingstyle.rst: Expand to include CONFIG_IS_ENABLED and PHASE_ Expand the conditional compilation section to explain when to use CONFIG_IS_ENABLED rather than IS_ENABLED and provide an example. Next, note what the PHASE_ macro is supposed to be used for as well. Signed-off-by: Tom Rini --- doc/develop/codingstyle.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/doc/develop/codingstyle.rst b/doc/develop/codingstyle.rst index 7211e4e4eed..bc18b2ebb7b 100644 --- a/doc/develop/codingstyle.rst +++ b/doc/develop/codingstyle.rst @@ -192,6 +192,25 @@ inside the block, and check it for correctness (syntax, types, symbol references, etc). Thus, you still have to use an #ifdef if the code inside the block references symbols that will not exist if the condition is not met. +When working with xPL (see :doc:`spl` for more information) we need to take +further care to use the right macro. In the case where a symbol may be +referenced with an xPL-specific Kconfig symbol, use the CONFIG_IS_ENABLED macro +instead, in a similar manner: + +.. code-block:: c + + if (CONIG_IS_ENABLED(SOMETHING)) { + ... + } + +When dealing with a Kconfig symbol that has both a normal name and one or more +xPL-prefixed names, the Makefile needs special consideration as well. The +PHASE\_ macro helps us in this situation thusly: + +.. code-block:: make + + obj-$(CONFIG_$(PHASE_)SOMETHING) += something.o + At the end of any non-trivial #if or #ifdef block (more than a few lines), place a comment after the #endif on the same line, noting the conditional expression used. For instance: