On Thu, 14 Feb 2019, Simon Wood wrote: > On Thu, February 14, 2019 9:42 am, Greg KH wrote: > > > That's because Android is using toybox's version of 'lsusb'. I > > recommend using the real version if you need this information. > > I would if I could, I do not control the BSP for this hardware :-( > > >> I have found the 'descriptors' file for the USB device under the '/sys' > >> interface, however this does not appear to contain the HUB specific > >> details. > > > > Really? It should, why does it not contain that information? That's a > > binary file that lists the USB descriptor information. You are going to > > have to "parse it by hand". The "descriptors" file in sysfs contains only the device and config descriptors -- that is, the data the device sends in response to Get-Device-Descriptor and Get-Config-Descriptor requests. In does not include other things, such as HID or report descriptors or hub descriptors. > Attached is a snap-shot of a (random) hub on Desktop linux. > > The 'HUB descriptor' is not contained within the 'descriptors' file from > the '/sys' interface, although I suspect that it can be accessed via > _another_ file within '/sys'.... hopefully someone can point me at it. No, there is no sysfs file containing the content of the hub descriptor. On the other hand, it's not too hard to write a program to retrieve the hub descriptor from a hub via usbfs or using libusb. Or you can just copy the code in lsusb. Alan Stern > Decoding is not hard with the power of the interwebs: > https://eleccelerator.com/usbdescreqparser/ > > > The 'descriptors' file from my suspect device (on Android) was attached to > original post. > > Thanks, > Simon.
