HI!
My noise meter (PCE-322a) has a USB serial adapter and it's attached to
a Raspberry PI 1B (armv6l) currently running Tumbleweed 20220814.
There's also a Wifi USB device attached to the RPI.
# lsusb
Bus 001 Device 057: ID 10c4:ea60 Silicon Labs CP210x UART Bridge
Bus 001 Device 056: ID 0bda:8179 Realtek Semiconductor Corp. RTL8188EUS
802.11n Wireless Network Adapter
Bus 001 Device 055: ID 0424:ec00 Microchip Technology, Inc. (formerly
SMSC) SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 054: ID 0424:9512 Microchip Technology, Inc. (formerly
SMSC) SMC9512/9514 USB Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
This hardware combo worked pretty well IIRC until including kernel
5.18.4 (or .5). But since a later upgrade the serial connection is
occassionally broken and I have to unload/reload the relevant kernel
modules (cp210x, usbserial) and restart my Python program.
I'm wondering how to track down what's going on.
dmesg shows messages like this:
[42865.396366] smsc95xx 1-1.1:1.0 eth0: hardware isn't capable of remote
wakeup
[42865.419194] smsc95xx 1-1.1:1.0 eth0: Link is Down
Therefore I already tried to avoid energy saving mode with some entries
in /etc/modprobe.d/. This feels to have somewhat improved reconnecting
WLAN after a while but did not help making the USB-serial connection
stable again.
Ciao, Michael.
