user@user-laptop:~$ sudo udevadm test /class /block /mmcblk0
run_command: calling: test
udevadm_test: version 147
This program is for debugging only, it does not run any program,
specified by a RUN key. It may show incorrect results, because
some values may be different, or not available at a simulation run.

parse_file: reading '/lib/udev/rules.d/40-gnupg.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-hplip.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-ia64.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-infiniband.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-isdn.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-libgphoto2-2.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-libpisock9.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-libsane.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-pilot-links.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-ppc.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-xserver-xorg-input-wacom.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-zaptel.rules' as rules file
parse_file: reading '/lib/udev/rules.d/45-fuse.rules' as rules file
parse_file: reading '/lib/udev/rules.d/45-libmtp8.rules' as rules file
parse_file: reading '/lib/udev/rules.d/50-firmware.rules' as rules file
parse_file: reading '/lib/udev/rules.d/50-udev-default.rules' as rules file
parse_file: reading '/lib/udev/rules.d/56-hpmud_support.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-cdrom_id.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-alsa.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-input.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-serial.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-storage-tape.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-storage.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-v4l.rules' as rules file
parse_file: reading '/lib/udev/rules.d/61-gnome-bluetooth-rfkill.rules' as rules file
parse_file: reading '/lib/udev/rules.d/61-mobile-action.rules' as rules file
parse_file: reading '/lib/udev/rules.d/61-option-modem-modeswitch.rules' as rules file
parse_file: reading '/lib/udev/rules.d/61-persistent-storage-edd.rules' as rules file
parse_file: reading '/lib/udev/rules.d/64-device-mapper.rules' as rules file
parse_file: reading '/lib/udev/rules.d/65-dmsetup.rules' as rules file
parse_file: reading '/lib/udev/rules.d/70-acl.rules' as rules file
parse_file: reading '/lib/udev/rules.d/70-hid2hci.rules' as rules file
parse_file: reading '/etc/udev/rules.d/70-persistent-cd.rules' as rules file
parse_file: reading '/etc/udev/rules.d/70-persistent-net.rules' as rules file
parse_file: reading '/lib/udev/rules.d/70-printers.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-cd-aliases-generator.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-net-description.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-persistent-net-generator.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-tty-description.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-ericsson-mbm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-zte-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/78-sound-card.rules' as rules file
parse_file: reading '/lib/udev/rules.d/79-fstab_import.rules' as rules file
parse_file: reading '/lib/udev/rules.d/80-alsa.rules' as rules file
parse_file: reading '/lib/udev/rules.d/80-drivers.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-brltty.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-hdparm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-hplj10xx.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-pcmcia.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-regulatory.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-hal.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-pulseaudio.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-usb-media-players.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-disks.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-dell.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-fujitsu.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-gateway.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-ibm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-lenovo.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-battery-recall-toshiba.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-csr.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-hid.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-devkit-power-wup.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-keymap.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-udev-late.rules' as rules file
parse_file: reading '/lib/udev/rules.d/97-bluetooth.rules' as rules file
udev_rules_new: rules use 181812 bytes tokens (15151 * 12 bytes), 28984 bytes buffer
udev_rules_new: temporary index used 49460 bytes (2473 * 20 bytes)
unable to open device '/sys/class'


Please your advice.....