BBB - WiFi adapter works after replug but not after reboot

General Discussion
1

I’ve been googling and reading and trying lots of things and feeling I’m starting to go in circles a bit now so thought I’d pause and ask for some help as it feels somewhat common perhaps for this WiFi adapter (MT7601U - Ralink) but I’m just not getting it.

It works great after unplugging the WiFi adapter and plugging it back in to the hub, but wlan0 and the entire WiFi USB device disappears after a reboot. Any hints on a reliable solution? Possibly a command to reset USB? A new driver? Even a new WiFi adapter perhaps? Something else perhaps?

Here’s some system info… Yell if some other info would be helpful…

root@beaglebone:/home/kyle# lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 10 (buster)
Release: 10
Codename: buster

root@beaglebone:/home/kyle# uname -r
4.19.94-ti-r74

root@beaglebone:/home/kyle# lshw -C network
*-usb:0
description: Wireless interface
product: MT7601U Wireless Adapter
vendor: Ralink Technology, Corp.
physical id: 2
bus info: usb@1:1.2
logical name: wlan0
version: 0.00
serial: 00:0c:43:00:5a:7a
capabilities: usb-2.01 ethernet physical wireless
configuration: broadcast=yes driver=mt7601u driverversion=4.19.94-ti-r74 firmware=N/A ip=192.168.1.59 link=yes maxpower=160mA multicast=yes speed=480Mbit/s wireless=IEEE 802.11

After reboot - Adapter and wlan0 missing
root@beaglebone:/home/kyle# lsusb
Bus 001 Device 008: ID 0d8c:000c C-Media Electronics, Inc. Audio Adapter
Bus 001 Device 007: ID 413c:2005 Dell Computer Corp. RT7D50 Keyboard
Bus 001 Device 002: ID 1a40:0201 Terminus Technology Inc. FE 2.1 7-port Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

After replug of adapter - Adapter and wlan0 active
root@beaglebone:/home/kyle# lsusb
Bus 001 Device 008: ID 0d8c:000c C-Media Electronics, Inc. Audio Adapter
Bus 001 Device 007: ID 413c:2005 Dell Computer Corp. RT7D50 Keyboard
Bus 001 Device 009: ID 148f:7601 Ralink Technology, Corp. MT7601U Wireless Adapter
Bus 001 Device 002: ID 1a40:0201 Terminus Technology Inc. FE 2.1 7-port Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Thanks for any thoughts you may have…

Cheers!
Kyle…

2

This smells like a power issue… On startup the BBB will pull up to 800mA and then finally settle below 500mA… How are you powering the board? (smells like it’s a brownout on startup when the wifi is plugged in)

Regards,

3

Ok… this is weird… Thank you for the idea on power… I thought I was in good shape there since both the BBB and the USB hub were each plugged in with their own power adapters. I unplugged the hub now to test options and rule that out since that for sure shouldn’t work, and it worked. I rebooted it again with the hub unplugged, and it worked successfully again. That seems opposite of what I would have expected perhaps.

I’m baffled by that one, but I’m ok with it. Does that make any sense? I’d like to understand why that is, but I’m definitely willing to just accept it and move forward as well… heh…

Thanks!
Kyle…