Blog

After getting a Razer Blade Stealth (late-2017 i7-8550U) model I noticed various issues with the touchpad using libinput under wayland. Lots of wobbling and overall a pretty bad user experience under linux. With a little research I expected these issues should have been fixed with with this change for the late-2017 model.

https://github.com/systemd/systemd/pull/8436

Turns out Razer has at least 2 device ids for the same laptop so I created an override to work around this issue.

Create /lib/udev/hwdb.d/61-evdev.hwdb with this in it:

# Razer Blade Stealth (override)
evdev:name:1A586757:00 06CB:8323 Touchpad:dmi:*svnRazer:pnBladeStealth:*
 EVDEV_ABS_00=::12:8
 EVDEV_ABS_01=::11:8
 EVDEV_ABS_35=::12:8
 EVDEV_ABS_36=::11:8

Then I ran the following commands to enable it

systemd-hwdb update
udevadm trigger /dev/input/event11

If you don’t know your device you can just reboot. Now all my libinput problems seem to be solved!

Update: I submitted a hwdb patch to systemd to address it there

After accidentally overwriting /etc/config/network on a TP-Link Archer C7 AC1750 V2 today… I went looking for ways to recover without a JTAG header and a FDTI adapter. Playing around with the reboot/reset I finally got it into some kind of recovery mode. I saw ARP 192.168.1.66 which is followed by it asking for ArcherC7v2_tp_recovery.bin.

Since as far as I can tell this feature is totally undocumented for the Archer C7 V2 and its addresses are slightly different from previous models. I figured I’d put this out there for anybody else looking to fix one of these things without resorting to a soldering iron.

First, install some kind of TFTP server

apt-get install atftpd

Download a factory image of OpenWrt. I use snapshots until chaos calmer is released since I want 802.11ac support in luci and iwinfo.

wget https://downloads.openwrt.org/snapshots/trunk/ar71xx/openwrt-ar71xx-generic-archer-c7-v2-squashfs-factory.bin

Make the router think its getting a normal recovery firmware

mv openwrt-ar71xx-generic-archer-c7-v2-squashfs-factory.bin /srv/tfptd/ArcherC7v2_tp_recovery.bin

Now, configure your network card for 192.168.1.66 and power on the router while holding down the reset button. The router itself will come up as 192.168.1.86 when in recovery mode. It should take a little bit to transfer and then restart. (lights will flash) After that you should be able to telnet to 192.168.1.1 and start configuring openwrt.