EG91 firmware incompatity

Technical Subjects Driver
,
1

We are having problems with an EG91 modem with EG91EXGAR10A03M1G_01.003.01.003 firmware revision and a 5.10.192 kernel. The kernel is no creating the corresponding USB devices. Also we have an other EG91 that have came with the EG91EXGAR08A16M1G_20.200.20.200 firmware revision and this is working correctly.

We will need to update the firmware version of the non working EG91 modem to EG91EXGAR08A16M1G_20.200.20.200 version to solve this. Could you provide us the fimware and tool to make the update in a linux ARM64 equip please?

Note: I´ve obtained the firmware with the response of AT+QGMR.

My email is iker.landaluce@seidor.com

Best regards.

2

I can send you the EG91EXGAR08A17M1G_20.200.20.200.

3

But I don’t understand what it means? Could you show me?

Please do not flash it. Please provide the IMEI of the modem.
I didn’t find the firmwware 91EXGAR10A03M1G and I am wondering that you flash the mdoem with an incorrect firmware.

4

Hello Bean. I attach you some screenshots of 2 equips with same OS, the only difference is the modem firmware. On left side you have the screenshots corresponding to the equip with EG91EXGAR08A16M1G_20.200.20.200 firmware, witch is working correctly, on the rigth side you have the NO OK working modem.

image
image1871×702 32.5 KB

image
image1785×605 55.6 KB

image
image1656×160 9.17 KB

5

It does not seems to be bug. The bcdDevice is not necessary.
You can show the

lsusb -t

cat /sys/kernel/debug/usb/devices

What we care about is the USB configuration descriptors 、interface descriptors and endpoint descriptors.

6

Here you have:

This is the result for the non working LTE (with 91EXGAR10A03M1G FW)
root@DS2023121272100038:~# lsusb -t
/: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Wireless, Driver=btusb, 480M
|__ Port 1: Dev 2, If 1, Class=Wireless, Driver=btusb, 480M
|__ Port 1: Dev 2, If 2, Class=Vendor Specific Class, Driver=rtl8821cu, 480M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ohci-platform/1p, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
|__ Port 1: Dev 6, If 3, Class=Vendor Specific Class, Driver=, 480M
|__ Port 1: Dev 6, If 1, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 1: Dev 6, If 4, Class=Vendor Specific Class, Driver=, 480M
|__ Port 1: Dev 6, If 2, Class=Vendor Specific Class, Driver=, 480M
|__ Port 1: Dev 6, If 0, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=ch341, 12M
|__ Port 3: Dev 4, If 0, Class=Vendor Specific Class, Driver=ch341, 12M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M
root@DS2023121272100038:~# cat /sys/kernel/debug/usb/devices

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= 5.10
S: Manufacturer=Linux 5.10.198 dwc2_hsotg
S: Product=DWC OTG Controller
S: SerialNumber=ff580000.usb
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=480 MxCh= 1
B: Alloc= 4/800 us ( 1%), #Int= 2, #Iso= 0
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0002 Rev= 5.10
S: Manufacturer=Linux 5.10.198 ehci_hcd
S: Product=EHCI Host Controller
S: SerialNumber=ff5c0000.usb
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=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 4
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=05e3 ProdID=0608 Rev=85.38
S: Product=USB2.0 Hub
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
E: Ad=81(I) Atr=03(Int.) MxPS= 1 Ivl=256ms

T: Bus=02 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 6 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=2c7c ProdID=0191 Rev= 0.00
S: Manufacturer=Quectel
S: Product=EG91-EX
S: SerialNumber=1234567890ABCDEF
C:* #Ifs= 5 Cfg#= 1 Atr=e0 MxPwr=500mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=83(I) Atr=03(Int.) MxPS= 64 Ivl=2ms
E: Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=fe Prot=ff Driver=(none)
E: Ad=85(I) Atr=03(Int.) MxPS= 64 Ivl=2ms
E: Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=87(I) Atr=03(Int.) MxPS= 64 Ivl=2ms
E: Ad=88(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

T: Bus=02 Lev=02 Prnt=02 Port=01 Cnt=02 Dev#= 3 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=ff(vend.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
P: Vendor=1a86 ProdID=7523 Rev= 2.64
S: Product=USB Serial
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr= 98mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=02 Driver=ch341
E: Ad=82(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=1ms

T: Bus=02 Lev=02 Prnt=02 Port=02 Cnt=03 Dev#= 4 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=ff(vend.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
P: Vendor=1a86 ProdID=7523 Rev= 2.64
S: Product=USB Serial
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr= 98mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=02 Driver=ch341
E: Ad=82(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=1ms

T: Bus=03 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 1
B: Alloc= 0/900 us ( 0%), #Int= 0, #Iso= 0
D: Ver= 1.10 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0001 Rev= 5.10
S: Manufacturer=Linux 5.10.198 ohci_hcd
S: Product=Generic Platform OHCI controller
S: SerialNumber=ff5d0000.usb
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= 2 Ivl=255ms

T: Bus=04 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= 5.10
S: Manufacturer=Linux 5.10.198 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=04 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=0bda ProdID=c820 Rev= 2.00
S: Manufacturer=Realtek
S: Product=802.11ac NIC
S: SerialNumber=123456
C:* #Ifs= 3 Cfg#= 1 Atr=a0 MxPwr=500mA
A: FirstIf#= 0 IfCount= 2 Cls=e0(wlcon) Sub=01 Prot=01
I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=1ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms
I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms
I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms
I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms
I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms
I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms
I:* If#= 2 Alt= 0 #EPs= 5 Cls=ff(vend.) Sub=ff Prot=ff Driver=rtl8821cu
E: Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=06(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=87(I) Atr=03(Int.) MxPS= 64 Ivl=500us
E: Ad=08(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

T: Bus=05 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= 5.10
S: Manufacturer=Linux 5.10.198 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
root@DS2023121272100038:~#

Here you have the other outout with the working firmware (EG91EXGAR08A16M1G):
root@DS2023121272100108:~# lsusb -t
/: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Wireless, Driver=btusb, 480M
|__ Port 1: Dev 2, If 1, Class=Wireless, Driver=btusb, 480M
|__ Port 1: Dev 2, If 2, Class=Vendor Specific Class, Driver=rtl8821cu, 480M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ohci-platform/1p, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
|__ Port 1: Dev 37, If 3, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 1: Dev 37, If 1, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 1: Dev 37, If 4, Class=Vendor Specific Class, Driver=, 480M
|__ Port 1: Dev 37, If 2, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 1: Dev 37, If 0, Class=Vendor Specific Class, Driver=option, 480M
|__ Port 2: Dev 3, If 0, Class=Vendor Specific Class, Driver=ch341, 12M
|__ Port 3: Dev 4, If 0, Class=Vendor Specific Class, Driver=ch341, 12M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M
root@DS2023121272100108:~# cat /sys/kernel/debug/usb/devices

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= 5.10
S: Manufacturer=Linux 5.10.198 dwc2_hsotg
S: Product=DWC OTG Controller
S: SerialNumber=ff580000.usb
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=480 MxCh= 1
B: Alloc= 4/800 us ( 1%), #Int= 3, #Iso= 0
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0002 Rev= 5.10
S: Manufacturer=Linux 5.10.198 ehci_hcd
S: Product=EHCI Host Controller
S: SerialNumber=ff5c0000.usb
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=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 4
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=05e3 ProdID=0608 Rev=85.38
S: Product=USB2.0 Hub
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
E: Ad=81(I) Atr=03(Int.) MxPS= 1 Ivl=256ms

T: Bus=02 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 37 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=2c7c ProdID=0191 Rev= 3.18
S: Manufacturer=Quectel
S: Product=EG91-EX
S: SerialNumber=0123456789ABCDEF
C:* #Ifs= 5 Cfg#= 1 Atr=a0 MxPwr=500mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
E: Ad=83(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
E: Ad=85(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
E: Ad=87(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=89(I) Atr=03(Int.) MxPS= 8 Ivl=32ms
E: Ad=88(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

T: Bus=02 Lev=02 Prnt=02 Port=01 Cnt=02 Dev#= 3 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=ff(vend.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
P: Vendor=1a86 ProdID=7523 Rev= 2.64
S: Product=USB Serial
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr= 98mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=02 Driver=ch341
E: Ad=82(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=1ms

T: Bus=02 Lev=02 Prnt=02 Port=02 Cnt=03 Dev#= 4 Spd=12 MxCh= 0
D: Ver= 1.10 Cls=ff(vend.) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
P: Vendor=1a86 ProdID=7523 Rev= 2.64
S: Product=USB Serial
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr= 98mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=02 Driver=ch341
E: Ad=82(I) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 32 Ivl=0ms
E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=1ms

T: Bus=03 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 1
B: Alloc= 0/900 us ( 0%), #Int= 0, #Iso= 0
D: Ver= 1.10 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0001 Rev= 5.10
S: Manufacturer=Linux 5.10.198 ohci_hcd
S: Product=Generic Platform OHCI controller
S: SerialNumber=ff5d0000.usb
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= 2 Ivl=255ms

T: Bus=04 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= 5.10
S: Manufacturer=Linux 5.10.198 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=04 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=0bda ProdID=c820 Rev= 2.00
S: Manufacturer=Realtek
S: Product=802.11ac NIC
S: SerialNumber=123456
C:* #Ifs= 3 Cfg#= 1 Atr=a0 MxPwr=500mA
A: FirstIf#= 0 IfCount= 2 Cls=e0(wlcon) Sub=01 Prot=01
I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=1ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms
I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms
I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms
I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms
I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms
I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms
E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms
I:* If#= 2 Alt= 0 #EPs= 5 Cls=ff(vend.) Sub=ff Prot=ff Driver=rtl8821cu
E: Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=06(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=87(I) Atr=03(Int.) MxPS= 64 Ivl=500us
E: Ad=08(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

T: Bus=05 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= 5.10
S: Manufacturer=Linux 5.10.198 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

7

OK the USB interface class descriptor is not the same.
Is it Ubuntu? could you send me the option.c (which should be in kdir/drivers/usb/serial/option.c)
What’s the Linux kernel version.

I think you can modfiy the option.c to make both work.

8

Hello Bean:

The kernel version is 5.10.198, provided by Rockchip.

If you give an idea of what should I modify I can make those modifications and recompile the kernel again. Here is my original file.
option.c (137.7 KB)

I´ve also compiled a kernel with the latest published option.c for 5.10.X, but the problem persists:
option.c « serial « usb « drivers - kernel/git/stable/linux.git - Linux kernel stable tree

9 
{ USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91),
 .driver_info = RSVD(4) },

Please try this.
option.c (137.8 KB)

10

The original is

	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0xff, 0xff),
	  .driver_info = NUMEP2 },
	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0, 0) },

It means that it only will match the USB interface with

USB class is 0xFF , subclass is 0xFF, proto is 0xFF and there is only 2 endpoints.

	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0xff, 0xff),
	  .driver_info = NUMEP2 },

And the follow means that it can only choose the USB class is 0xFF, and the subclass & proto is 0x0.

	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EG91, 0xff, 0, 0) },
11

Hello Bean.

I´ve recompiled the kernel overriding my option.c by the file you provide and seems now is working. Now my system detects the modem with the EG91EXGAR08A16M1G_20.200.20.200 firmware and is able to stand up a connection with that LTE module. Also is working with the EG91EXGAR08A16M1G_20.200.20.200 firmware.

Thanks for your support

12

Great!

And yes the two firmware there is a difference in USB configuration.