--- /dev/null
+# ==========================================================================
+# Cleaning up
+# ==========================================================================
+
+src := $(obj)
+
+PHONY := __clean
+__clean:
+
+# Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
+# Usage:
+# $(Q)$(MAKE) $(clean)=dir
+clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj
+
+# The filename Kbuild has precedence over Makefile
+kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
+include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)
+
+# Figure out what we need to build from the various variables
+# ==========================================================================
+
+__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y)))
+subdir-y += $(__subdir-y)
+__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m)))
+subdir-m += $(__subdir-m)
+__subdir-n := $(patsubst %/,%,$(filter %/, $(obj-n)))
+subdir-n += $(__subdir-n)
+__subdir- := $(patsubst %/,%,$(filter %/, $(obj-)))
+subdir- += $(__subdir-)
+
+# Subdirectories we need to descend into
+
+subdir-ym := $(sort $(subdir-y) $(subdir-m))
+subdir-ymn := $(sort $(subdir-ym) $(subdir-n) $(subdir-))
+
+# Add subdir path
+
+subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn))
+
+# build a list of files to remove, usually releative to the current
+# directory
+
+__clean-files := $(extra-y) $(EXTRA_TARGETS) $(always) \
+ $(targets) $(clean-files) \
+ $(host-progs) \
+ $(hostprogs-y) $(hostprogs-m) $(hostprogs-)
+
+# as clean-files is given relative to the current directory, this adds
+# a $(obj) prefix, except for absolute paths
+
+__clean-files := $(wildcard \
+ $(addprefix $(obj)/, $(filter-out /%, $(__clean-files))) \
+ $(filter /%, $(__clean-files)))
+
+# as clean-dirs is given relative to the current directory, this adds
+# a $(obj) prefix, except for absolute paths
+
+__clean-dirs := $(wildcard \
+ $(addprefix $(obj)/, $(filter-out /%, $(clean-dirs))) \
+ $(filter /%, $(clean-dirs)))
+
+# ==========================================================================
+
+quiet_cmd_clean = CLEAN $(obj)
+ cmd_clean = rm -f $(__clean-files)
+quiet_cmd_cleandir = CLEAN $(__clean-dirs)
+ cmd_cleandir = rm -rf $(__clean-dirs)
+
+
+__clean: $(subdir-ymn)
+ifneq ($(strip $(__clean-files)),)
+ +$(call cmd,clean)
+endif
+ifneq ($(strip $(__clean-dirs)),)
+ +$(call cmd,cleandir)
+endif
+ifneq ($(strip $(clean-rule)),)
+ +$(clean-rule)
+endif
+ @:
+
+
+# ===========================================================================
+# Generic stuff
+# ===========================================================================
+
+# Descending
+# ---------------------------------------------------------------------------
+
+PHONY += $(subdir-ymn)
+$(subdir-ymn):
+ $(Q)$(MAKE) $(clean)=$@
+
+# If quiet is set, only print short version of command
+
+cmd = @$(if $($(quiet)cmd_$(1)),echo ' $($(quiet)cmd_$(1))' &&) $(cmd_$(1))
+
+
+# Declare the contents of the .PHONY variable as phony. We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)
