Search the DD-WRT forums there are several threads over there where people are trying to flash back to the default Linksys firmware, there was one guy who claimed to have successfully flashed back. See the last post in that link for the information and how he went back to the Linksys firmware.

Replace firmware with DD-WRT NOTE: Replacing the factory firmware is different for every router. In this example we will replace the firmware on a Linksys WRT54GL .If you have a different router, find your solution here to replace the factory default firmware with DD-WRT. Linksys WRT54GL + DD-WRT software My intention was to try out and report on the DD-WRT software project. Both the WRT54G and the WRT54GL are supposed to work with DD-WRT, however, their may be issues with WRT54G. The following documents the trouble free flashing steps I followed to install DD-WRT on a WRT54GL router. Presumably, the L stands for Linux. DD-WRT Forum :: View topic - Uninstall DD-WRT on Linksys Jan 12, 2007 DD-WRT Forum :: View topic - Linksys WRT54G/GL/GS Feb 27, 2016

Sep 27, 2017 · The DD-WRT open source firmware of today is based on the Linksys WRT firmware developed for its WRT54G series of routers. The ‘DD’ part of DD-WRT is a hat tip to the license plate code for the city of Dresden, Germany, where the primary maintainer of the DD-WRT project lives.

How to Install DD-WRT on Linksys WRT54G2 V1 Firmware Dec 18, 2012 How To Install and Configure OpenVPN On Your DD-WRT Router Jul 11, 2017

Linksys WRT54G/GL/GS/GX - DD-WRT Wiki

Install DD-WRT firmware on a Linksys Router - Duration: 6:49. 3CITech 108,166 views. 6:49. Unbrick a Linksys WRT54G router with DD WRT and TFTP - Duration: 8:22.