Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2

From: Kever Yang
Date: Mon Nov 17 2014 - 09:25:43 EST

On 11/14/2014 11:55 PM, Alan Stern wrote:
On Thu, 13 Nov 2014, Julius Werner wrote:

Another thing might be that the port connect interrupt does not
correctly resume the root hub. I don't really know many details about
how that works, and it seems pretty complicated. But I can see that
all other HCDs seem to call usb_hcd_resume_root_hub() from their
interrupt handlers, which we don't. There's also a
That's how a root hub sends a wakeup request to the kernel. The
controller issues an interrupt, and when the HCD's interrupt handler
sees that the root hub is suspended, it calls usb_hcd_resume_root_hub()
instead of trying to query the hardware (because in general you _can't_
query the hardware while it's in a low-power state).
Thanks Alan and Julius, just like what you have mentioned, the dwc2 miss the
usb_hcd_resume_root_hub() when root hub is suspended and device connect

I have send another patch for that, hope it did the right thing.

- Kever

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