diff mbox series

[v3,2/4] usb: aspeed-vhub: fix remote wakeup failure in iKVM use case

Message ID 20211208100545.1441397-3-neal_liu@aspeedtech.com
State New
Headers show
Series [v3,1/4] usb: aspeed-vhub: add qualifier descriptor | expand

Commit Message

Neal Liu Dec. 8, 2021, 10:05 a.m. UTC
Signaling remote wakeup if an emulated USB device has any activity
if the device is allowed by host.

Signed-off-by: Neal Liu <neal_liu@aspeedtech.com>
---
 drivers/usb/gadget/udc/aspeed-vhub/epn.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Greg KH Dec. 13, 2021, 2:01 p.m. UTC | #1
On Wed, Dec 08, 2021 at 06:05:43PM +0800, Neal Liu wrote:
> Signaling remote wakeup if an emulated USB device has any activity
> if the device is allowed by host.
> 
> Signed-off-by: Neal Liu <neal_liu@aspeedtech.com>
> ---
>  drivers/usb/gadget/udc/aspeed-vhub/epn.c | 5 +++++
>  1 file changed, 5 insertions(+)

What commit does this fix?

Does it need to go to stable kernels?

Should it be independent of this patch series that adds new features?

thanks,

greg k-h
Neal Liu Dec. 27, 2021, 2:07 a.m. UTC | #2
> -----Original Message-----
> From: Neal Liu
> Sent: Monday, December 20, 2021 10:23 AM
> To: Benjamin Herrenschmidt <benh@kernel.crashing.org>; Felipe Balbi
> <balbi@kernel.org>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Joel
> Stanley <joel@jms.id.au>; Andrew Jeffery <andrew@aj.id.au>; Cai Huoqing
> <caihuoqing@baidu.com>; Tao Ren <rentao.bupt@gmail.com>; Julia Lawall
> <julia.lawall@inria.fr>; kernel test robot <lkp@intel.com>; Sasha Levin
> <sashal@kernel.org>; linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org;
> linux-arm-kernel@lists.infradead.org; linux-aspeed@lists.ozlabs.org
> Cc: BMC-SW <BMC-SW@aspeedtech.com>
> Subject: RE: [PATCH v3 2/4] usb: aspeed-vhub: fix remote wakeup failure in
> iKVM use case
> 
> > -----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
> > <balbi@kernel.org>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>;
> > Joel Stanley <joel@jms.id.au>; Andrew Jeffery <andrew@aj.id.au>; Cai
> > Huoqing <caihuoqing@baidu.com>; Tao Ren <rentao.bupt@gmail.com>; Julia
> > Lawall <julia.lawall@inria.fr>; kernel test robot <lkp@intel.com>;
> > Sasha Levin <sashal@kernel.org>; linux-usb@vger.kernel.org;
> > linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> > linux-aspeed@lists.ozlabs.org
> > Cc: BMC-SW <BMC-SW@aspeedtech.com>
> > 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:
> > > 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
diff mbox series

Patch

diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
index 917892ca8753..ccc239b5cc17 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
@@ -381,6 +381,11 @@  static int ast_vhub_epn_queue(struct usb_ep* u_ep, struct usb_request *u_req,
 	} else
 		u_req->dma = 0;
 
+	if (ep->dev->wakeup_en) {
+		EPVDBG(ep, "Wakeup host first\n");
+		ast_vhub_hub_wake_all(vhub);
+	}
+
 	EPVDBG(ep, "enqueue req @%p\n", req);
 	EPVDBG(ep, " l=%d dma=0x%x zero=%d noshort=%d noirq=%d is_in=%d\n",
 	       u_req->length, (u32)u_req->dma, u_req->zero,