Comment 0 for bug 1927037

Expected behavior:
Network adapter should be visible via `iw list`, `iwconfig`, and `ifconfig`.

Actual behavior:
Network adapter is visible in `lspci` and `lshw`, but not in `iw list`, `iwconfig`, or `ifconfig`

Details:
The Atheros network card is detected by the ath9k driver when installed into a machine with x86_64 architecture. When the same card is installed into a miniPCIe-to-PCIe adapter, then plugged into a Raspberry Pi CM4 IO breakout board, the network adapter can be seen via lspci and lshw but is not seen by iw, iwconfig, or ifconfig.

lspci:
ubuntu@ubuntu:~$ sudo lspci -v
00:00.0 PCI bridge: Broadcom Inc. and subsidiaries Device 2711 (rev 20) (prog-if 00 [Normal decode])
 Flags: bus master, fast devsel, latency 0, IRQ 41
 Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
 I/O behind bridge: 00000000-00000fff [size=4K]
 Memory behind bridge: f8000000-f80fffff [size=1M]
 Prefetchable memory behind bridge: [disabled]
 Capabilities: [48] Power Management version 3
 Capabilities: [ac] Express Root Port (Slot-), MSI 00
 Capabilities: [100] Advanced Error Reporting
 Capabilities: [180] Vendor Specific Information: ID=0000 Rev=0 Len=028 <?>
 Capabilities: [240] L1 PM Substates
 Kernel driver in use: pcieport

01:00.0 Network controller: Qualcomm Atheros AR93xx Wireless Network Adapter (rev 01)
 Subsystem: Qualcomm Atheros AR93xx Wireless Network Adapter
 Flags: fast devsel, IRQ 255
 Memory at 600000000 (64-bit, non-prefetchable) [disabled] [size=128K]
 Expansion ROM at 600020000 [virtual] [disabled] [size=64K]
 Capabilities: [40] Power Management version 3
 Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
 Capabilities: [70] Express Endpoint, MSI 00
 Capabilities: [100] Advanced Error Reporting
 Capabilities: [140] Virtual Channel
 Capabilities: [300] Device Serial Number 00-00-00-00-00-00-00-00

-----
lshw:
ubuntu@ubuntu:~$ sudo lshw -c net
  *-network UNCLAIMED
       description: Network controller
       product: AR93xx Wireless Network Adapter
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:01:00.0
       version: 01
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress cap_list
       configuration: latency=0
       resources: memory:600000000-60001ffff memory:600020000-60002ffff
  *-network
       description: Ethernet interface
       physical id: 1
       logical name: eth0
       serial: dc:a6:32:f4:69:36
       size: 1Gbit/s
       capacity: 1Gbit/s
       capabilities: ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=bcmgenet driverversion=v2.0 duplex=full ip=REDACTED link=yes multicast=yes port=MII speed=1Gbit/s

-----
iw list/iwconfig:
ubuntu@ubuntu:~$ iw list
ubuntu@ubuntu:~$ iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

-----
ubuntu@ubuntu:~$ lsb_release -rd
Description: Ubuntu 20.04.2 LTS
Release: 20.04

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: linux-image-5.4.0-1034-raspi 5.4.0-1034.37
ProcVersionSignature: User Name 5.4.0-1034.37-raspi 5.4.101
Uname: Linux 5.4.0-1034-raspi aarch64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: arm64
CasperMD5CheckResult: skip
Date: Tue May 4 02:59:25 2021
ImageMediaBuild: 20210201.1
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=C.UTF-8
 SHELL=/bin/bash
SourcePackage: linux-raspi
UpgradeStatus: No upgrade log present (probably fresh install)