[PATCH] dt-bindings: Add a help message when dtschema tools are missing

[Rob Herring <robh@kernel.org>]

The dtschema version check works, but is not that clear when dtschema is
neither installed nor in the PATH. Add a separate check and message if
dt-doc-validate is not found.

Cc: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/Makefile | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/Makefile b/Documentation/devicetree/bindings/Makefile
index 8d6d912c6a6a..001b4f62b741 100644
--- a/Documentation/devicetree/bindings/Makefile
+++ b/Documentation/devicetree/bindings/Makefile
@@ -9,6 +9,10 @@ DT_SCHEMA_MIN_VERSION = 2021.2.1
 
 PHONY += check_dtschema_version
 check_dtschema_version:
+	@which $(DT_DOC_CHECKER) >/dev/null || \
+		{ echo "Error: '$(DT_DOC_CHECKER)' not found!" \
+		"\nEnsure dtschema python package is installed and in your PATH." \
+		"\nCurrent PATH is:\n$$PATH\n" >&2; false; }
 	@{ echo $(DT_SCHEMA_MIN_VERSION); \
 	$(DT_DOC_CHECKER) --version 2>/dev/null || echo 0; } | sort -Vc >/dev/null || \
 	{ echo "ERROR: dtschema minimum version is v$(DT_SCHEMA_MIN_VERSION)" >&2; false; }
-- 
2.32.0