summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/dev-tools/checkpatch.rst9
-rwxr-xr-xscripts/checkpatch.pl12
2 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst
index 76bd0ddb0041..d5c47e560324 100644
--- a/Documentation/dev-tools/checkpatch.rst
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -495,6 +495,15 @@ Comments
See: https://lore.kernel.org/lkml/20131006222342.GT19510@leaf/
+ **UNCOMMENTED_RGMII_MODE**
+ Historically, the RGMII PHY modes specified in Device Trees have been
+ used inconsistently, often referring to the usage of delays on the PHY
+ side rather than describing the board.
+
+ PHY modes "rgmii", "rgmii-rxid" and "rgmii-txid" modes require the clock
+ signal to be delayed on the PCB; this unusual configuration should be
+ described in a comment. If they are not (meaning that the delay is realized
+ internally in the MAC or PHY), "rgmii-id" is the correct PHY mode.
Commit message
--------------
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 664f7b7a622c..f597734d83cc 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3741,6 +3741,18 @@ sub process {
}
}
+# Check for RGMII phy-mode with delay on PCB
+ if ($realfile =~ /\.(dts|dtsi|dtso)$/ &&
+ $line =~ /^\+\s*(phy-mode|phy-connection-type)\s*=\s*"/ &&
+ !ctx_has_comment($first_line, $linenr)) {
+ my $prop = $1;
+ my $mode = get_quoted_string($line, $rawline);
+ if ($mode =~ /^"rgmii(?:|-rxid|-txid)"$/) {
+ WARN("UNCOMMENTED_RGMII_MODE",
+ "$prop $mode without comment -- delays on the PCB should be described, otherwise use \"rgmii-id\"\n" . $herecurr);
+ }
+ }
+
# check for using SPDX license tag at beginning of files
if ($realline == $checklicenseline) {
if ($rawline =~ /^[ \+]\s*\#\!\s*\//) {