BBB-blank-debian-8.6-console-armhf-2016-12-18-2gb image doesn't show up as a serial device

Hi,

I’ve just installed this image ( https://rcn-ee.com/rootfs/bb.org/testing/2016-12-18/console/BBB-blank-debian-8.6-console-armhf-2016-12-18-2gb.img.xz ) on a BBB rev C, and a BBB with the 2GB flash. Both are behaving the same. They show up as an ethernet device, but not as a serial port. lsusb on the host confirms that they are not behaving as a serial port:

`

Bus 003 Device 030: ID 0525:a4a2 Netchip Technology, Inc. Linux-USB Ethernet/RNDIS Gadget
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 2 Communications
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0525 Netchip Technology, Inc.
idProduct 0xa4a2 Linux-USB Ethernet/RNDIS Gadget
bcdDevice 4.04
iManufacturer 1 BeagleBoard.org
iProduct 2 BeagleBoneBlack
iSerial 3 2513BBBK4941
bNumConfigurations 2
OTG Descriptor:
bLength 3
bDescriptorType 9
bmAttributes 0x03
SRP (Session Request Protocol)
HNP (Host Negotiation Protocol)
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 78
bNumInterfaces 2
bConfigurationValue 2
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 2
bFunctionClass 2 Communications
bFunctionSubClass 6 Ethernet Networking
bFunctionProtocol 0
iFunction 6 RNDIS
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 2 Communications
bInterfaceSubClass 2 Abstract (modem)
bInterfaceProtocol 255 Vendor Specific (MSFT RNDIS?)
iInterface 4 RNDIS Communications Control
CDC Header:
bcdCDC 1.10
CDC Call Management:
bmCapabilities 0x00
bDataInterface 1
CDC ACM:
bmCapabilities 0x00
CDC Union:
bMasterInterface 0
bSlaveInterface 1
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0008 1x 8 bytes
bInterval 9
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 10 CDC Data
bInterfaceSubClass 0 Unused
bInterfaceProtocol 0
iInterface 5 RNDIS Ethernet Data
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 91
bNumInterfaces 2
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 2
bFunctionClass 2 Communications
bFunctionSubClass 6 Ethernet Networking
bFunctionProtocol 0
iFunction 11 CDC ECM
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 2 Communications
bInterfaceSubClass 6 Ethernet Networking
bInterfaceProtocol 0
iInterface 8 CDC Ethernet Control Model (ECM)
CDC Header:
bcdCDC 1.10
CDC Union:
bMasterInterface 0
bSlaveInterface 1
CDC Ethernet:
iMacAddress 9 9059af55826a
bmEthernetStatistics 0x00000000
wMaxSegmentSize 1514
wNumberMCFilters 0x0000
bNumberPowerFilters 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0010 1x 16 bytes
bInterval 9
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 10 CDC Data
bInterfaceSubClass 0 Unused
bInterfaceProtocol 0
iInterface 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 1
bNumEndpoints 2
bInterfaceClass 10 CDC Data
bInterfaceSubClass 0 Unused
bInterfaceProtocol 0
iInterface 10 CDC Ethernet Data
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Device Qualifier (for other device speed):
bLength 10
bDescriptorType 6
bcdUSB 2.00
bDeviceClass 2 Communications
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
bNumConfigurations 2
Device Status: 0x0000
(Bus Powered)

`

I have two BBGW which appear fine as ttyACM0 and ttyACM1, but I haven’t reflashed them from the stock image. Is there a way to enable this on the BBB image?

Thanks,
Jeremy

Just as an update, unloading the g_ether and loading g_serial results in a working serial port at /dev/ttyGS0. Of course, the usb ethernet doesn’t work after this, and the modules can’t be loaded at the same time.

modprobe g_serial

modprobe: ERROR: could not insert ‘g_serial’: No such device

rmmod g_ether

modprobe g_serial

systemctl start serial-getty@ttyGS0.service

resulting host lsusb:

Bus 003 Device 033: ID 0525:a4a7 Netchip Technology, Inc. Linux-USB Serial Gadget (CDC ACM mode)
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 2 Communications
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0525 Netchip Technology, Inc.
idProduct 0xa4a7 Linux-USB Serial Gadget (CDC ACM mode)
bcdDevice 4.04
iManufacturer 1 Linux 4.4.39-ti-r75 with musb-hdrc
iProduct 2 Gadget Serial v2.4
iSerial 0
bNumConfigurations 1
OTG Descriptor:
bLength 3
bDescriptorType 9
bmAttributes 0x03
SRP (Session Request Protocol)
HNP (Host Negotiation Protocol)
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 78
bNumInterfaces 2
bConfigurationValue 2
iConfiguration 4 CDC ACM config
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 500mA
Interface Association:
bLength 8
bDescriptorType 11
bFirstInterface 0
bInterfaceCount 2
bFunctionClass 2 Communications
bFunctionSubClass 2 Abstract (modem)
bFunctionProtocol 1 AT-commands (v.25ter)
iFunction 7 CDC Serial
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 2 Communications
bInterfaceSubClass 2 Abstract (modem)
bInterfaceProtocol 1 AT-commands (v.25ter)
iInterface 5 CDC Abstract Control Model (ACM)
CDC Header:
bcdCDC 1.10
CDC Call Management:
bmCapabilities 0x00
bDataInterface 1
CDC ACM:
bmCapabilities 0x02
line coding and serial state
CDC Union:
bMasterInterface 0
bSlaveInterface 1
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x000a 1x 10 bytes
bInterval 9
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 10 CDC Data
bInterfaceSubClass 0 Unused
bInterfaceProtocol 0
iInterface 6 CDC ACM Data
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Device Qualifier (for other device speed):
bLength 10
bDescriptorType 6
bcdUSB 2.00
bDeviceClass 2 Communications
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
bNumConfigurations 1
Device Status: 0x0000
(Bus Powered)

Thanks,
Jeremy

You can see the logic here:

https://github.com/RobertCNelson/boot-scripts/blob/master/boot/am335x_evm.sh#L389-L424

g_multi requires a file option, and the console image lack's a 2nd
partition, img file etc... So it defaults to g_ether.

Moving to configfs usb will fix this but i'm just starting to figure
configfs out..

https://github.com/RobertCNelson/boot-scripts/blob/master/boot/omap3_beagle.sh#L44-L86

So till then, grab the "iot" image..

Regards,

Hi Robert,

Thanks, that makes sense. Will reflash with the iot image.

Thanks,
Jeremy