I guess you just need hid_generic and usbhid for usb keyboard. You may not need anymore those you mention for using usb keyboard at boot: ehci-hcd, ehci-pci, ohci-hcd or uhci-hcd.
You have upgraded to 14.1? run again /usr/share/mkinitrd/mkinitrd_command_generator.sh in 14.1 should clarify the modules you need.
Check the changelog in days before version Slackware 14.1 was been released:
Tue Oct 29 05:03:04 UTC 2013
In mkinitrd_command_generator.sh, if a USB keyboard is detected add the
hid_generic module (in addition to usbhid). Recent kernels need this.
Thanks to mario.