checkpatch: check usleep_range() arguments

usleep_range() shouldn't use the same args for min and max.

Report it when it happens and when both args are decimal and min > max.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Yuval Mintz <yuvalmin@broadcom.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3e04f80..4bad570 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3313,6 +3313,22 @@ sub process {
                        }
                }
 
+# check usleep_range arguments
+               if ($^V && $^V ge 5.10.0 &&
+                   defined $stat &&
+                   $stat =~ /^\+(?:.*?)\busleep_range\s*\(\s*($FuncArg)\s*,\s*($FuncArg)\s*\)/) {
+                       my $min = $1;
+                       my $max = $7;
+                       if ($min eq $max) {
+                               WARN("USLEEP_RANGE",
+                                    "usleep_range should not use min == max args; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
+                       } elsif ($min =~ /^\d+$/ && $max =~ /^\d+$/ &&
+                                $min > $max) {
+                               WARN("USLEEP_RANGE",
+                                    "usleep_range args reversed, use min then max; see Documentation/timers/timers-howto.txt\n" . "$here\n$stat\n");
+                       }
+               }
+
 # check for new externs in .c files.
                if ($realfile =~ /\.c$/ && defined $stat &&
                    $stat =~ /^.\s*(?:extern\s+)?$Type\s+($Ident)(\s*)\(/s)