On Wed, 2020-07-15 at 00:51 +0000, Peter Chen wrote:

quoted

quoted

The Toradex Colibri iMX6ULL board has a special USB hardware design.
With runtime-pm enabled USB reset itself continuously. Furthermore
the OTG port is also not enumerating devices if the Chipidea IP is
in runtime sleep mode and a device or host gets plugged in.

Hi Philippe,

You may describe the detail what's the special USB hardware design for
your board,

If I only knew the root-cause of that problem - unfortunately I don't.
That's also why I have such a hard time to describe it.

quoted

and why it causes the problem, and why disable runtime pm could fix
this issue, then,

I cannot provide the 'why' part yet. I'll try something more and hope I can provide
you guys with the exact description.

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the other users could know if it could apply to their platforms or not
in future.

I only found out about it because you were pointing me in that direction. I debugged
for hours now and didn't came to the root-cause of the issue. I think to really
understand it I would need to know much more about the Chipidea IP.

I'll get back to you guys with a proposal for a new description.

Philippe, is it possible to share your USB hardware design at 6ULL?
And how ci_hdrc_gadget_connect is called when the runtime pm is disabled?

Thanks,
Peter
 
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