• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 97 subscribers
  • Views 274 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Errata Advisory: 1.0.11 Attached Non-Compliant USB device responding to Spurious Invalid Short Packet

rader
Prodigy 205 points

Advisory 1.0.11 in the AM335X Silicon Rev 1.0 Errata (sprz360b) describes a problem with the USB PHY timing which could cause the USB host to create a spurious, invalid short packet. Normally this invalid short packet would be ignored by a fully complaint device.

However the Advisory goes on to state "at least one mass storage USB device has been found to be non-compliant to the USB specification, by responding to this packet"

Could you please let us know the vendor ID / Product ID for this device which exposed this issue, we would like to detect and flag that device during enumeration so we can avoid a USB bug hang.

I realize in a perfect world, we would simply require all of our end-users to only use fully compliant devices. However, sometimes that is not practical so any help we can give the end-user by notifying him when he does use non-compliant devices is useful.

 

  • 0
    TI__Mastermind 27890 points

    There really isn't much of a point to flagging devices based on VID/PID given the following:

    • The issue could occur during enumeration just as easily as after enumeration.
    • The issue is such that it requires a 'perfect storm' of variables to occur.
    Most importantly, USB device manufacturers *routinely* assign the same PID/VID to devices that use completely different USB device controllers. Two examples of the same device, using the same PID/VID, can exhibit markedly different behavior due to device controller/firmware changes.
    We do expect for this issue to be resolved in the next spin of the AM335x.