USB Overcurrent Detection failed when USB has been initialized from u-boot

nad — Tue, 17 Jul 2018 12:35:31 GMT

Hi,

I am working on a i.MX6 custom board running linux version 3.10.17.

The USB OTG works fine both in host and gadget mode and overcurrent events are reported as expected by the kernel.

   root@mx6board:~# echo host > /sys/kernel/debug/ci_hdrc.0/role
   root@mx6board:~# cat /sys/class/regulator/regulator.7/state
   enabled
   => Trigger overcurrent

    kernel: hub 2-0:1.0: hub_resume
   kernel: hub 2-0:1.0: over-current condition on port 1
   root@mx6board:~# cat /sys/class/regulator/regulator.7/state
   disabled

However, when initiating USB from u-boot using 'usb start', overcurrent events are no longer reported by the kernel.

   mx6board> usb start;
   mx6board> boot
   ...
   root@mx6board:~# echo host > /sys/kernel/debug/ci_hdrc.0/role
   root@mx6board:~# cat /sys/class/regulator/regulator.7/state
   enabled
   => Trigger overcurrent
   root@mx6board:~# cat /sys/class/regulator/regulator.7/state
   enabled

Someone may give advices ?

Re: USB Overcurrent Detection failed when USB has been initialized from u-boot

igorpadykov — Thu, 19 Jul 2018 23:41:01 GMT

Hi nad

L3.10.17 is very old kernel, may be recommended to try latest 4.x nxp official releases described on

https://www.nxp.com/support/developer-resources/run-time-software/i.mx-developer-resources/i.mx-6series-i.mx-7series-software-and-development-tool-resources:IMX_SW

For 3.10.17 one can dump usb module registers in both cases and try to debug it using

Chapter 41 CHIPIDEA USB Driver attached Linux Manual.

Best regards
igor
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topic USB Overcurrent Detection failed when USB has been initialized from u-boot in i.MX Processors

USB Overcurrent Detection failed when USB has been initialized from u-boot

Re: USB Overcurrent Detection failed when USB has been initialized from u-boot