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 <tr...@konsulko.com>
---
Changes in v2:
- New patch.
---
doc/develop/codingstyle.rst | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/doc/develop/codingstyle.rst b/doc/develop/codingstyle.rst
index 7211e4e4eed1..3303fff165de 100644
--- a/doc/develop/codingstyle.rst
+++ b/doc/develop/codingstyle.rst
@@ -192,6 +192,23 @@ 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.
+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:
--
2.43.0
