iMX7 cannot enter LPSR mode when USB is connected

[senthilkumarcha]

Hi, 

We are working in a custom board with imx7d processor. In that we have implemented LPSR mode. Normally the board can enter LPSR mode and wake up using GPIO pin. But when a USB device is connected to the board, it enters deep sleep mode(Suspend to RAM) instead of LPSR mode. Also In mx7d-sabresd we got the same result.

Why the processor cannot enter LPSR mode when USB device is connected ? 

Has anyone faced issues like this ?

Please help us to resolve this issue.

Thanks in advance,

C.Senthilkumar

[igorpadykov]

Hi Senthilkumar

before entering LPSR mode one can try to remove usb device, using suggestions on

Eject USB drives / eject command - Unix & Linux Stack Exchange 

Best regards
igor
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[senthilkumarcha]

Hi Igor,
Is this the one way to solve the issue ?

Can you explain why the processor cannot enter LPSR mode when USB device is connected ? 

Thanks and regards,

C.Senthilkumar

[igorpadykov]

Hi Senthilkumar

had you tried to remove usb device from linux using "eject".

LPSR mode is not supported in official NXP BSPs, suggest to use

Professional Services for debugging this issue
NXP Professional Services|NXP 

Best regards
igor