vpelletier
commented
2 years ago Configfs (on the jetson nano) has a fixed bMaxPacketSize0 of 64 (seems not able to be changed - I have tried setting this but it is ignored)
I checked the USB 2 and 3 specs, and this seems to be what the standard requires for high-speed devices, with low- and full-speed devices limited to powers of two from 8 to 64, and super-speed devices limited to 512 (encoded as 0x09).
linux hosts dont do this - they just fail the first enumeration. I realise that this is probably Jetson Nano specific but does this sound like it could be the issue?
This could be UDC-specific (which, if I'm reading the devicetrees right, seem to be tegra-xudc), as enumeration should be in the hands of the UDC - which also means this issue will likely have to be brought to this code's maintainers.
Here is the output from the linux host side when checking enumeration:
Mmh, but if this is present on the host, then it must mean the USB enumeration worked.
For reference, I pasted below what I get on a Linux host with the dummy_hcd UDC.
The differences I spot at a glance are:
- bcdDevice is 4.09 in your case, which means kernel 4.9 . In my experience, the gadget subsystem evolves very quickly, with bugs very regularly being fixed. If it is possible (...which may not be easy with vendor-provided images), I would recommend trying on a recent kernel.
- Multiple
(error)s while trying to get string descriptors despite running lsusb as root. This looks like a bug. - I'm less sure about the broken report descriptor: in my understanding the "UNAVAILABLE" I'm getting from
lsusbis because HID descriptors require access to the device (these are retrieved from aGet_Descriptorrequest targeting the interface - and hence requiring the device to be opened bylsusb, which is not possible once X opened it). This means there is more than just string descriptor retrieval which would be broken, standard requests delegated to the interface may be broken too.
$ sudo lsusb -vd 1d6b:0104
Bus 005 Device 015: ID 1d6b:0104 Linux Foundation Multifunction Composite Gadget
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0104 Multifunction Composite Gadget
bcdDevice 5.10
iManufacturer 1 python-functionfs
iProduct 2 HID mouse demo
iSerial 3
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 0x0022
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 4 mouse demo function
bmAttributes 0x80
(Bus Powered)
MaxPower 500mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 3 Human Interface Device
bInterfaceSubClass 0
bInterfaceProtocol 0
iInterface 0
HID Device Descriptor:
bLength 9
bDescriptorType 33
bcdHID 1.11
bCountryCode 0 Not supported
bNumDescriptors 1
bDescriptorType 34 Report
wDescriptorLength 50
Report Descriptors:
** UNAVAILABLE **
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0003 1x 3 bytes
bInterval 10
Device Qualifier (for other device speed):
bLength 10
bDescriptorType 6
bcdUSB 2.00
bDeviceClass 0
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
bNumConfigurations 1
Device Status: 0x0000
(Bus Powered)
KiwiLostInMelb
Hi,
I have a really weird issue and wonder if it is related to chunking when sending the report descriptor to the host side.
Device and background: Jetson Nano with latest jetpack, disabled jetson default configfs service, disabled udev rules for the same - I.e. configfs all ready to work.
Scenario: Your HID Mouse test app works fine when I have a windows host connected although there is an initial connect, disconnect and connect.
But when I connect the same to a linux host I get enumeration issues which is really weird. It almost seems as if there is something chunking the writes for linux whereas windows tries something first, fails and then requests smaller chunks one at a time?
Configfs (on the jetson nano) has a fixed bMaxPacketSize0 of 64 (seems not able to be changed - I have tried setting this but it is ignored) and it might be that your library is limiting report descriptor ep0 transfers to a lower buffer size - possibly based on endpoint bLength (which is 7 for this one) instead of bMaxPacketSize0?
It seems like windows handles this - hence the connect (at highest rate?), disconnect and then reconnect (at a fixed lower buffer size set in windows?) but linux hosts dont do this - they just fail the first enumeration. I realise that this is probably Jetson Nano specific but does this sound like it could be the issue?
I'm not really a python programmer. I'm using python for ease of integration into a webcam detection routine. Hence I'm looking for a bit of help here.
Im pulling my hair out on this one :)
Here is the output from the linux host side when checking enumeration:
sudo lsusb -d1d6b:0104 -v
Bus 001 Device 010: ID 1d6b:0104 Linux Foundation Multifunction Composite Gadget Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.10 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x1d6b Linux Foundation idProduct 0x0104 Multifunction Composite Gadget bcdDevice 4.09 iManufacturer 1 (error) iProduct 2 (error) iSerial 3 (error) bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 34 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 4 (error) bmAttributes 0x80 (Bus Powered) MaxPower 500mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 0 No Subclass bInterfaceProtocol 0 None iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 1.11 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 50 Warning: incomplete report descriptor Report Descriptor: (length is 7) Item(Main ): (null), data=none Item(Main ): (null), data=none Item(Main ): (null), data=none Item(Main ): (null), data=none Item(Main ): (null), data=none Item(Main ): (null), data=none Item(Main ): (null), data=none Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0003 1x 3 bytes bInterval 10 Device Status: 0x0401 Self Powered