-----Original Message-----
From: Neal Liu
Sent: Monday, December 20, 2021 10:23 AM
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>; Felipe Balbi
[off-list ref]; Greg Kroah-Hartman [off-list ref]; Joel
Stanley [off-list ref]; Andrew Jeffery [off-list ref]; Cai Huoqing
[off-list ref]; Tao Ren [off-list ref]; Julia Lawall
[off-list ref]; kernel test robot [off-list ref]; Sasha Levin
[off-list ref]; linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org;
linux-arm-kernel@lists.infradead.org; linux-aspeed@lists.ozlabs.org
Cc: BMC-SW <redacted>
Subject: RE: [PATCH v3 2/4] usb: aspeed-vhub: fix remote wakeup failure in
iKVM use case

quoted

-----Original Message-----
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Sent: Tuesday, December 14, 2021 10:36 AM
To: Neal Liu <neal_liu@aspeedtech.com>; Felipe Balbi
[off-list ref]; Greg Kroah-Hartman [off-list ref];
Joel Stanley [off-list ref]; Andrew Jeffery [off-list ref]; Cai
Huoqing [off-list ref]; Tao Ren [off-list ref]; Julia
Lawall [off-list ref]; kernel test robot [off-list ref];
Sasha Levin [off-list ref]; linux-usb@vger.kernel.org;
linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
linux-aspeed@lists.ozlabs.org
Cc: BMC-SW <redacted>
Subject: Re: [PATCH v3 2/4] usb: aspeed-vhub: fix remote wakeup
failure in iKVM use case

On Thu, 2021-12-09 at 02:37 +0000, Neal Liu wrote:

quoted

I'm confused. Signaling Wakeup when wakeup_en is set if it has any
ep activities is not exactly what you said?

wakeup_en is set only if host allows this device have wakeup
capability and bus being suspended.

Normal ep activities would not write the MMIO because wakeup_en is
not set.

Hrm... I didn't think wakeup_en was limited to the bus being
suspended, but maybe I misremember, it's been a while.

Cheers,
Ben.

wakeup_en is only set in the case of host set USB_DEVICE_REMOTE_WAKEUP
feature to vhub devices.
I think this behavior only occurs during host is going to suspend, and set this
feature to any device which can wakeup itself before sleep.
Thanks

-Neal

Would you like to test it if you have some free time.
Please feel free for any feedback.

-Neal