I found out that during boot touchscreen is disabled and official Huawei Launcher enables it, so if you install alternative launcher, touchscreen remains disabled after reboot.
First of all, you have to root you S7 Slim (I've done it using following article http://android-dls.com/wiki/index.ph...ck_Boot_Images, just set ro.secure=0 in default.prop and add --base 0x20000000 to mkbootimg command-line). Then, copy file /system/etc/bluetooth_power.sh to your hard disk (adb pull /system/etc/bluetooth_power.sh c:\). Edit that file (c:\bluetooth_power.sh) using Notepad++ and add following lines:
echo 1 > /sys/cap_touchscreen/boot_complete
echo 1 > /sys/cap_touchscreen/state
Then, remount /system partiton read-write (adb remount), and copy that file back (adb push c:\bluetooth_power.sh /system/etc/).
Reboot, and now you can install any launcher you like!