Some additional details on wifi issues. I’ve had a Radxa Zero running as the controller for a multi-zone smart heating system.
The system has been running for a couple weeks, however after about 5.5 days without any changes or reboots, wifi became non-responsive.
Connecting a monitor and keyboard showed errors to the console indicating the wifi module was unable to return from sleep, namely:
[495167.523518] ieee80211 phy0: brcmf_proto_bcdc_query_dcmd: brcmf_proto_bcdc_msg failed w/status -110
[495167.532223] brcmfmac: brcmf_sdio_bus_sleep: error while changing bus sleep state -110
[495167.534935] brcmfmac: brcmf_sdio_txfail: sdio error, abort command and terminate frame
[495167.537791] brcmfmac: brcmf_sdio_txfail: sdio error, abort command and terminate frame
[495167.540588] brcmfmac: brcmf_sdio_txfail: sdio error, abort command and terminate frame
[495167.543293] brcmfmac: brcmf_sdio_dpc: sdio ctrlframe tx failed err=-100
[495167.545856] brcmfmac: brcmf_sdio_dpc: failed backplane access over SDIO, halting operation
[495167.545869] ieee80211 phy0: brcmf_proto_bcdc_query_dcmd: brcmf_proto_bcdc_msg failed w/status -110
[495167.551001] ieee80211 phy0: brcmf_cfg80211_get_station: GET STA INFO failed, -110
[495167.928131] brcmfmac: brcmf_sdio_bus_sleep: error while changing bus sleep state -100
[495167.931032] brcmfmac: brcmf_sdio_txfail: sdio error, abort command and terminate frame
which was repeating ad nauseam. Logging in and unloading the related modules with rmmod brcmfmac cfg80211 brmutil ended the error output, however reloading the modules and restarting the networking daemon with systemctl restart networking still offered no wlan0 device accessible via ifconfig or iwconfig.
While typically my last resort, a reboot returned the wlan0 connection. Looking at the current settings via
iwconfig wlan0 showed among other things:
…
Power Management:on
…
Disabling this is simply a matter of running:
iwconfig wlan0 power off
Making this permanent can either be via adding that command to /etc/rc.local or updating the NetworkManager powersave default config.
Hope this helps somebody else 