Looks like the Realcrap Ethernet in the dongle attached to my laptop has died. The image on my test device doesn't have ext4 support so I can't transfer files with a USB stick. Trying to enable wireless gives me a cryptic netifd: radio0 (1256): sh: out of range log message. I don't see a serial-transfer option in U-Boot.
Is there a way, with a master build without additional packages, to transfer a binary image (4 MB) over serial to the device?
This doesn't answer the original question, but would it be a work around to possibly to put an intermediate device where you connect to the laptop wireless-ly?
Wireless isn't coming up (WIP on a new port) -- netifd: radio0 (1256): sh: out of range that I haven't been able to track down yet. (Looks like I don't have hostapd in the build.)
I understand. What I was saying that you use another router/switch/AP, connect your laptop to it via wireless and connect your test device to it using Ethernet cable.
Ah, good plan! I knew there was a reason I packed a third router with me...
Edit: From "m4t" on IRC
regarding serial transfer, no, but this might work: https://raw.githubusercontent.com/mateusza/shellscripthttpd/master/base64.sh
(as there are no plain-text decoding utilities installed by default under OpenWrt)