U-Boot requires Kconfig options to be indented with tabs, whereas Linux
allows spaces. Add a U-Boot specific check to warn when spaces are used
for indentation in Kconfig files.

To ensure this check is executed, move the u_boot_line() invocation in
process() to occur before the valid source file check. Previously,
Kconfig files were skipped by the file extension filter before the
U-Boot specific checks could run.

Example warning:

WARNING: Kconfig indentation should use tabs
+    bool

Link: https://lore.kernel.org/u-boot/20251222162026.GA847766@bill-the-cat/
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

This resyncs us with the version found in v6.17 of the Linux kernel with
the following exceptions:
- Keep our u-boot specific tests / code area.
- Keep the location of our checkpatch.rst
- Change the "use strscpy" test as we don't have that to strlcpy
- Keep debug/printf in the list for $logFunctions
- Keep checks to "env" files
- Keep our tests for strncpy/strncat

This also syncs the spdxcheck.py tool and all the associated
documentation.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
[trini: Keep our strlcpy/cat check]
Signed-off-by: Tom Rini <trini@konsulko.com>

In order for the U-Boot specific tests we've added (along with the long
line test) to be run on ".env" files as well, we need to update the line
in the process function that starts to limit the file extensions that we
test on.

Signed-off-by: Tom Rini <trini@konsulko.com>

The defines for the different build phases shouldn't be used in device
trees, currently they aren't even defined for device tree pre processing,
resulting in build errors.

Link: https://lists.denx.de/pipermail/u-boot/2025-March/582787.html
Signed-off-by: Hendrik Donner <hd@os-cillation.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

A problem we have today is that some instances of IS_ENABLED(FOO) have
crept in to the code. This is in turn because with checkpatch.pl this is
only a warning and not an error, so they were overlooked. And looking
deeper, in the Linux kernel this pattern is allowed because
IS_ENABLED(DEFINED_FLAG) is allowed if discouraged and a quick skim of
the instances I saw in the current kernel follow this pattern. In U-Boot
however, this is not allowed, so bump to an error.

Signed-off-by: Tom Rini <trini@konsulko.com>

At this point in time we should not add common.h to any new files, so
make checkpatch.pl complain.

Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Simon Glass <sjg@chromium.org>

Have checkpatch.pl skip warnings for use of fdtdec_* functions in
ooling; livetree isn't used there.

Signed-off-by: Lars Feyaerts <lars@bitbiz.be>
Reviewed-by: Simon Glass <sjg@chromium.org>

Help ensure that these don't creep into development by adding a check in
checkpatch for them.

Signed-off-by: Simon Glass <sjg@chromium.org>

Now that all CONFIG symbols are in Kconfig, checkpatch.pl should check
for and error on any case of define/undef CONFIG_*.

Signed-off-by: Tom Rini <trini@konsulko.com>

This resyncs us with the version found in v5.16 of the Linux kernel with
the following exceptions:
- Keep our u-boot specific tests / code area.
- Change the location of checkpatch.rst
- Drop the "use strscpy" test as we don't have that, but do have strlcpy
  and want that used now.
- Keep debug/printf in the list for $logFunctions

This also syncs the spdxcheck.py tool and all the associated
documentation.
S
Signed-off-by: Simon Glass <sjg@chromium.org>