Tool/software: Linux
Dear TI folks,
I'm posting on this forum because we are currently facing an issue with the TI USB hub chip TUSB2046B connected to a Microchop USB3320. The transceiver is connected to a Zynq7000 processor. We tested with linux 3.19 and 5.0-rc7.
The issue we have with the hub is the following. We observe that the communication hangs when we connect a USB mouse and a USB mass-storage device to the hub. As long as no transfer is done with any of the device, there is no issue. But as soon as we start transferring data with the USB mass-storage device, the hub seems to hang. The laser of the mouse shuts down and never comes up again and the transfer on the USB mass-storage device hangs. The devices seem not to been seen anymore by the hub. Note that a keyboard and a mouse work without issue. But a mouse/keyboard connected together with a mass-storage device doesn't.
We took a USB capture with tcpdump on the bus when the issue happens. attached it to this post. You can see at the end of the trace that the GET_DESCRIPTOR request ends up with a -ENOENT status. In the trace you'll see that we started just before a transfer on the mass-storage device and that it suddenly stops to work.
Do you know some incompatibility between the TUSB2046B and USB3320? We did the same test with a microchip hub behind the USB3320 and didn't see any issue. Similarly, we ordered a TI evaluation board with this hub and connected it to a PC and didn't see the issue.
Thanks for your support,
Olivier
