The USB controller in OTG mode and acting as self-powered device does not generate a port change interrupt when the session is no longer valid (VBUS not present). To work around this, software can enable the B session end interrupt to detect when the VBUS voltage level drops.
Impact: |
Minor. Refer to the workaround. |
Workaround: |
The two-step work-around is described in the Workaround Details. |
Configurations Affected: |
Systems that use the USB controller in OTG mode. |
| Device Revision(s) Affected: | All, no plan to fix. Refer to (Xilinx Answer 47916) - Zynq-7000 Design Advisory Master Answer Record |
Workaround Details
The following software steps can be followed to detect a disconnect from the host:
Note: The VBUS comparator interrupts are de-bounced for 1ms, so it will take 1ms to 2ms for the interrupt to be asserted from the time the disconnect has occurred.