systemd/etc/udev/debian/hotplug.rules

ACTION!="add", GOTO="hotplug_not_add_event"

# check if the device has already been claimed by a driver
ENV{PHYSDEVDRIVER}=="?*", GOTO="hotplug_driver_loaded"

# workarounds for kernels which lack $MODALIAS support
SUBSYSTEM=="ieee1394",	ENV{MODALIAS}!="?*", \
	IMPORT{program}="/lib/udev/modalias_ieee1394"
SUBSYSTEM=="serio",	ENV{MODALIAS}!="?*", \
	IMPORT{program}="/lib/udev/modalias_serio"

# load the drivers
ENV{MODALIAS}=="?*",	RUN+="/sbin/modprobe $env{MODALIAS}"
SUBSYSTEM=="ide",	ENV{MODALIAS}!="?*",	RUN+="/lib/udev/ide.agent"
#SUBSYSTEM=="input",	ENV{MODALIAS}!="?*",	RUN+="/lib/udev/input.agent"
SUBSYSTEM=="vio",	ENV{MODALIAS}!="?*",	RUN+="/lib/udev/vio.agent"

SUBSYSTEM=="pnp",	ENV{MODALIAS}!="?*",	RUN+="/bin/sh -c 'while read id; do /sbin/modprobe pnp:d$$id; done < /sys$devpath/id'"

SUBSYSTEM=="pcmcia_socket",			RUN+="/sbin/modprobe pcmcia"

SUBSYSTEM=="scsi_device", SYSFS{type}=="0|7|14", RUN+="/sbin/modprobe sd_mod"
SUBSYSTEM=="scsi_device", SYSFS{type}=="1",	RUN+="/sbin/modprobe osst", \
	SYSFS{vendor}=="Onstream", SYSFS{model}!="ADR*"
SUBSYSTEM=="scsi_device", SYSFS{type}=="1",	RUN+="/sbin/modprobe st", \
	SYSFS{vendor}=="Onstream", SYSFS{model}=="ADR*"
SUBSYSTEM=="scsi_device", SYSFS{type}=="1",	RUN+="/sbin/modprobe st", \
	SYSFS{vendor}!="Onstream"
SUBSYSTEM=="scsi_device", SYSFS{type}=="[345]",	RUN+="/sbin/modprobe sr_mod"
SUBSYSTEM=="scsi_device", SYSFS{type}=="[235689]", RUN+="/sbin/modprobe sg"

# From here on follows the hotplug agents which do not load modules
LABEL="hotplug_driver_loaded"

# FIXME: does a sane default exist?
#SUBSYSTEM=="scsi_device", SYSFS{idVendor}=="...", \
#	RUN+="/lib/udev/scsi-re-add"

SUBSYSTEM=="firmware",		RUN+="/lib/udev/firmware.agent"

LABEL="hotplug_not_add_event"

SUBSYSTEM=="net",		RUN+="/bin/sh -c '/lib/udev/net.agent &'"

# Log every event to /dev/hotplug.log (for debugging).
#RUN+="/lib/udev/logger.agent"