cmake: modules: extension for HW board revision format

Add the combination of Letter and Number(s) for the Revision
format of the Hardware Board.
This is for example used for nucleo_stm32f401re rev C01

Signed-off-by: Francois Ramu <[email protected]>

Author: FRASTM

cmake/modules/extensions.cmake

@@ -849,7 +849,9 @@ endfunction()
 # When `EXACT` is not specified, this function will set the Zephyr build system
 # variable `ACTIVE_BOARD_REVISION` with the selected revision.
 #
-# FORMAT <LETTER | NUMBER | MAJOR.MINOR.PATCH>: Specify the revision format.
+# FORMAT <ALPHANUM | LETTER | NUMBER | MAJOR.MINOR.PATCH>: Specify the revision format.
+#         ALPHANUM:           Revision format is a single letter from A - Z
+#                             followed by one or two integer number  ('C02')
 #         LETTER:             Revision format is a single letter from A - Z.
 #         NUMBER:             Revision format is a single integer number.
 #         MAJOR.MINOR.PATCH:  Revision format is three numbers, separated by `.`,
@@ -915,7 +917,9 @@ function(board_check_revision)
     endif()
   endif()
 
-  if(BOARD_REV_FORMAT STREQUAL LETTER)
+  if(BOARD_REV_FORMAT STREQUAL ALPHANUM)
+    set(revision_regex "([A-Z][0-9]+)")
+  elseif(BOARD_REV_FORMAT STREQUAL LETTER)
     set(revision_regex "([A-Z])")
   elseif(BOARD_REV_FORMAT STREQUAL NUMBER)
     set(revision_regex "([0-9]+)")
@@ -935,7 +939,7 @@ function(board_check_revision)
     endif()
   else()
     message(FATAL_ERROR "Invalid format specified for \
-    `board_check_revision(FORMAT <LETTER | NUMBER | MAJOR.MINOR.PATCH>)`")
+    `board_check_revision(FORMAT <ALPHANUM | LETTER | NUMBER | MAJOR.MINOR.PATCH>)`")
   endif()
 
   if(NOT (BOARD_REVISION MATCHES "^${revision_regex}$"))

doc/hardware/porting/board_porting.rst

@@ -641,6 +641,30 @@ example will result in the following error message:
 
    Board revision `0.7.0` not found.  Please specify a valid board revision.
 
+Alphanum revision matching
+==========================
+
+Let's say instead that you need to support revisions ``A0``, ``C01``, and ``C02`` of
+the ``plank`` board. Create the following additional files in the board
+directory:
+
+.. code-block:: none
+
+   boards/<ARCH>/plank
+   ├── plank_A0.conf
+   ├── plank_A0.overlay
+   ├── plank_C01.conf
+   ├── plank_C01.overlay
+   ├── plank_C02.conf
+   ├── plank_C02.overlay
+   └── revision.cmake
+
+And add the following to :file:`revision.cmake`:
+
+.. code-block:: cmake
+
+   board_check_revision(FORMAT ALPHANUM)
+
 Letter revision matching
 ========================
 
@@ -694,7 +718,7 @@ board_check_revision() details
 
 .. code-block:: cmake
 
-   board_check_revision(FORMAT <LETTER | NUMBER | MAJOR.MINOR.PATCH>
+   board_check_revision(FORMAT <ALPHANUM | LETTER | NUMBER | ALPHANUM | MAJOR.MINOR.PATCH>
                         [EXACT]
                         [DEFAULT_REVISION <revision>]
                         [HIGHEST_REVISION <revision>]
@@ -703,6 +727,7 @@ board_check_revision() details
 
 This function supports the following arguments:
 
+* ``FORMAT ALPHANUM``: matches single letter followed by integer revisions
 * ``FORMAT LETTER``: matches single letter revisions from ``A`` to ``Z`` only
 * ``FORMAT NUMBER``: matches integer revisions
 * ``FORMAT MAJOR.MINOR.PATCH``: matches exactly three digits. The command line