Part Number: AM3351
Hi,
we have a problem similar to: http://e2e.ti.com/support/arm/sitara_arm/f/791/p/414696/1474199#pi316653=1 That thread is unfortunately unanswered.
Our system is running linux 4.1.33.
When we connect a usb memory stick to our am3351 usb0 port, sometimes we get a VBUS failure: the am3351 asserts VBUS, but doesn't wait 100ms before deasserting it. We see that DRVVBUS is deasserted after only 2ms.
On the console we get:
[ 256.453865] musb-hdrc musb-hdrc.0.auto: VBUS_ERROR in a_wait_vrise (90, <VBusValid), retry #3, port1 0008010c
as you can see, DRVVBUS is deasserted after 2ms with VBUS = 3.6V.
We have a 1uF capacitor on VBUS.
What can shall we look at?
Thanking you in advance, best regards
Massimo
