https://bugzilla.kernel.org/show_bug.cgi?id=213839

Jonathan McDowell (noodles@earth.li) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |noodles@earth.li

--- Comment #5 from Jonathan McDowell (noodles@earth.li) ---

I've just ended up with one of these devices and see the same behaviour; on
Linux (5.10.70 from Debian) only 3 ports are operational, whereas when plugged
into a Windows laptop all 7 ports work. It seems this is a knock-off hub - it
was sold as 480Mb/s capable, but is only reporting itself as full-speed
(12Mb/s).

As Tomas reports it shows up as 2 USB hubs - lsusb -vv output as follows:

Bus 003 Device 080: ID 0a05:7211 Unknown Manufacturer hub
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         0 Full speed (or root) hub
  bMaxPacketSize0         8
  idVendor           0x0a05 Unknown Manufacturer
  idProduct          0x7211 hub
  bcdDevice            1.00
  iManufacturer           0 
  iProduct                1 USB2.0 HUB
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0019
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0001  1x 1 bytes
        bInterval             255

Apparently the chip involved is a Micov MW7211 which is a single chip
full-speed hub solution. I've no particular interest in seeing this work, given
that it's not high-speed capable, but figured the additional information might
be helpful as there's obviously some difference in the way Windows is driving
the hub compared to Linux.

-- 
You may reply to this email to add a comment.

You are receiving this mail because:
You are watching the assignee of the bug.