AnsweredAssumed Answered

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

Question asked by nad on Jul 17, 2018
Latest reply on Jul 19, 2018 by igorpadykov

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 ?

Outcomes