ASUS RT-AC1300UHP with OpeWRT 19.7, USB port died

Three questions arise for me.
Is it possible to repair the USB port?
If yes, how to repair?
If no or too costly, is a raspberry Pi3 with OpenWRT an equivalent replacement?

Short version
"... We don't know the algorithms for LPM for this host, disabling LPM."
"... INFO: ganged switching.
WARN: Port indicators are NOT supported."

Long version
The RT-AC1300UHP contacts the Wan via Ethernet (DHPC) and provides filtered services (gateway, DNS, firewall ...) for an intranet (max. 20 devices) via Ethernet and Wlan (5 and 2.4 Ghz). The USB port serves as a manual interface for fallback wifi via USB tethering, when the internet provider is tinkering or in case of line damage (so now for 4 days).
When the Internet connection fails, I connect my XPERIA_XZ2 via USB Thegering with the router and usually have no problems. Upgrading from 19.07.3 to 19.07.4 had no noticeable effect either. This time I connected my SM-T211 (Samsung Galaxy).
Normally the SM-T211 (Samsung Galaxy) is not recognized at all (original firmware) or only as a media device (OpenWRT). After trying different cables, the aged "Galaxy" worked fine all day and I could update the installed software without any problems. The next morning, however, the USB port was no longer usable. An upgrade to 19.07.5 brought no change to the current situation. The USB port is no longer responsive and does not supply power.

Please take into account that I am an end user and my English is very basic.

Please have a look at the attachment. I have a suspicion and have already started searching. But it can also be a hardware defect of the three months old router.

Thanks for any help

PS: Found the LED settings. USB LED can be turned on, but only exclusively with "defaulton" as trigger. Port remains dead.
PS2: I am online again with UMTS hotspot via Wlan. Respect and thanks to the developers of LuCi. Multiwan, operating mode change, Vlan, Firewall ... in one mask. The settings for disabled mode are retained, absolutely unique.

HARDWARE:
ASUS RT-AC1300UHP
1x USB3
ENVIRONMENT:
$ uname -a
Linux gateway 4.14.209 #0 SMP Sun Dec 6 07:31:03 2020 armv7l GNU/Linux

OPERATING SYSTEM:
$ cat /etc/os-release

Summary
NAME="OpenWrt"
VERSION="19.07.5"
ID="openwrt"
ID_LIKE="lede openwrt"
PRETTY_NAME="OpenWrt 19.07.5"
VERSION_ID="19.07.5"
HOME_URL="https://openwrt.org/"
BUG_URL="https://bugs.openwrt.org/"
SUPPORT_URL="https://forum.openwrt.org/"
BUILD_ID="r11257-5090152ae3"
OPENWRT_BOARD="ipq40xx/generic"
OPENWRT_ARCH="arm_cortex-a7_neon-vfpv4"
OPENWRT_TAINTS=""
OPENWRT_DEVICE_MANUFACTURER="OpenWrt"
OPENWRT_DEVICE_MANUFACTURER_URL="https://openwrt.org/"
OPENWRT_DEVICE_PRODUCT="Generic"
OPENWRT_DEVICE_REVISION="v0"
OPENWRT_RELEASE="OpenWrt 19.07.5 r11257-5090152ae3"

INSTALLED USB-PACKAGES:
$ opkg list-installed | grep -i usb

Summary
kmod-usb-core - 4.14.209-1
kmod-usb-dwc3 - 4.14.209-1
kmod-usb-dwc3-of-simple - 4.14.209-1
kmod-usb-ehci - 4.14.209-1
kmod-usb-ledtrig-usbport - 4.14.209-1
kmod-usb-net - 4.14.209-1
kmod-usb-net-cdc-ether - 4.14.209-1
kmod-usb-net-ipheth - 4.14.209-1
kmod-usb-net-rndis - 4.14.209-1
kmod-usb-ohci - 4.14.209-1
kmod-usb-ohci-pci - 4.14.209-1
kmod-usb-storage - 4.14.209-1
kmod-usb-storage-uas - 4.14.209-1
kmod-usb-uhci - 4.14.209-1
kmod-usb2 - 4.14.209-1
kmod-usb2-pci - 4.14.209-1
kmod-usb3 - 4.14.209-1
libusb-1.0-0 - 1.0.22-2
libusbmuxd - 2019-03-23-873252dc-2
usbmuxd - 2019-03-04-b1b0bf39-1
usbutils - 007-10

KERNEL MESSAGES:
$ dmesg | grep -i usb

Summary
[    0.028465] usbcore: registered new interface driver usbfs
[    0.028529] usbcore: registered new interface driver hub
[    0.028612] usbcore: registered new device driver usb
[    0.044900] tcsr 194b000.tcsr: setting usb hs phy mode select = e700e7
[    9.444717] xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 1
[    9.466822] hub 1-0:1.0: USB hub found
[    9.479775] xhci-hcd xhci-hcd.0.auto: new USB bus registered, assigned bus number 2
[    9.485122] xhci-hcd xhci-hcd.0.auto: Host supports USB 3.0  SuperSpeed
[    9.492811] usb usb2: We don't know the algorithms for LPM for this host, disabling LPM.
[    9.499934] hub 2-0:1.0: USB hub found
[    9.515198] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 3
[    9.538229] hub 3-0:1.0: USB hub found
[    9.551231] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 4
[    9.556502] xhci-hcd xhci-hcd.1.auto: Host supports USB 3.0  SuperSpeed
[    9.564158] usb usb4: We don't know the algorithms for LPM for this host, disabling LPM.
[    9.571177] hub 4-0:1.0: USB hub found
[   16.857828] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[   17.055926] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
[   17.081638] uhci_hcd: USB Universal Host Controller Interface driver
[   17.166708] usbcore: registered new interface driver usb-storage
[   17.174784] usbcore: registered new interface driver uas
[   20.639386] usbcore: registered new interface driver ipheth
[   20.703210] usbcore: registered new interface driver cdc_ether
[   20.752385] usbcore: registered new interface driver rndis_host

DETECTED USB-HADWARE:
$ lsusb -t
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/0p, 5000M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
Connected hardware (stick, drives, phones) is not recognized.

DEBUG INFO USB-HARDWARE:
$ cat /sys/kernel/debug/usb/devices

Summary
T:  Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=1d6b ProdID=0002 Rev= 4.14
S:  Manufacturer=Linux 4.14.209 xhci-hcd
S:  Product=xHCI Host Controller
S:  SerialNumber=xhci-hcd.0.auto
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

T:  Bus=02 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=5000 MxCh= 1
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 3.00 Cls=09(hub  ) Sub=00 Prot=03 MxPS= 9 #Cfgs=  1
P:  Vendor=1d6b ProdID=0003 Rev= 4.14
S:  Manufacturer=Linux 4.14.209 xhci-hcd
S:  Product=xHCI Host Controller
S:  SerialNumber=xhci-hcd.0.auto
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

T:  Bus=03 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=480  MxCh= 1
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 2.00 Cls=09(hub  ) Sub=00 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=1d6b ProdID=0002 Rev= 4.14
S:  Manufacturer=Linux 4.14.209 xhci-hcd
S:  Product=xHCI Host Controller
S:  SerialNumber=xhci-hcd.1.auto
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=hub
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

T:  Bus=04 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#=  1 Spd=5000 MxCh= 0
B:  Alloc=  0/800 us ( 0%), #Int=  0, #Iso=  0
D:  Ver= 3.00 Cls=09(hub  ) Sub=00 Prot=03 MxPS= 9 #Cfgs=  1
P:  Vendor=1d6b ProdID=0003 Rev= 4.14
S:  Manufacturer=Linux 4.14.209 xhci-hcd
S:  Product=xHCI Host Controller
S:  SerialNumber=xhci-hcd.1.auto
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=  0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub  ) Sub=00 Prot=00 Driver=(none)
E:  Ad=81(I) Atr=03(Int.) MxPS=   4 Ivl=256ms

GPIO:
The following commands run under user root

Which GPIO are defined?
$ ls -al /sys/class/gpio

Summary
drwxr-xr-x    2 root     root             0 Jan  1  1970 .
drwxr-xr-x   35 root     root             0 Jan  1  1970 ..
--w-------    1 root     root          4096 Jan  1  1970 export
lrwxrwxrwx    1 root     root             0 Jan  1  1970 gpiochip0 -> ../../devices/platform/soc/1000000.pinctrl/gpio/gpiochip0
--w-------    1 root     root          4096 Jan  1  1970 unexport

Query the value of the existing "gpiochip0"
$ cat /sys/class/gpio/gpiochip0/value
cat: can't open '/sys/class/gpio/gpiochip0/value': No such file or directory

$ ls -al /sys/devices/platform/soc/1000000.pinctrl/gpio/gpiochip0

Summary
drwxr-xr-x    2 root     root             0 Jan  1  1970 .
drwxr-xr-x    3 root     root             0 Jan  1  1970 ..
-r--r--r--    1 root     root          4096 Dec 16 13:28 base
lrwxrwxrwx    1 root     root             0 Dec 16 13:28 device -> ../../../1000000.pinctrl
-r--r--r--    1 root     root          4096 Dec 16 13:28 label
-r--r--r--    1 root     root          4096 Dec 16 13:28 ngpio
lrwxrwxrwx    1 root     root             0 Dec 16 13:28 subsystem -> ../../../../../../class/gpio
-rw-r--r--    1 root     root          4096 Dec 16 13:28 uevent

$ cat /sys/class/gpio/gpiochip0/device/uevent

Summary
DRIVER=ipq4019-pinctrl
OF_NAME=pinctrl
OF_FULLNAME=/soc/pinctrl@1000000
OF_COMPATIBLE_0=qcom,ipq4019-pinctrl
OF_COMPATIBLE_N=1
MODALIAS=of:NpinctrlT<NULL>Cqcom,ipq4019-pinctrl

Switch on the only existing pin
$ echo "1" > /sys/class/gpio/gpiochip0/export
-ash: can't create /sys/class/gpio/gpiochip0/export: Permission denied
OpenWRT does not have a group for "GPIO"

$ hub-ctrl -v

Summary
Hub #0 at 002:001
 INFO: ganged switching.
 WARN: Port indicators are NOT supported.
 Hub Port Status:
Hub #1 at 004:001
 INFO: ganged switching.
 WARN: Port indicators are NOT supported.
 Hub Port Status:

$ hub-ctrl -h 1 -P 1 -p 1
failed to control.
: Broken pipe

$ hub-ctrl -h 0 -P 1 -p 1
No response received
No change under "hub-ctrl -v".

I have now worked through all the posts I found. Does anyone have any ideas? I did not try overwriting the "libudev" with a version from OpenWRT 17.n because I did not find this file in my running system.

1: possible. but good luck.

2: Unless you have knowledge of electronics and how circuit boards are wired, forget it.

3: not equivalent but doable.

Thanks Neheb, even if it looks very dark.

  1. I see the lucky ones, on the other shore.
  2. I have no idea, bad eyes, shaky hands, but I can still hit the trash can opening. Extremely depressing how quickly routers are consumed here.
  3. This will be my second post.