lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 9 Nov 2017 09:17:05 -0600 From: Dinh Nguyen <dinguyen@...nel.org> To: Ivid Suvarna <ivid.suvarna@...il.com>, Alan Stern <stern@...land.harvard.edu> Cc: USB list <linux-usb@...r.kernel.org>, balbi@...nel.org, gregkh@...uxfoundation.org, Billy Araujo <billyaraujo@...il.com>, johnyoun@...opsys.com, Felipe Balbi <felipe.balbi@...ux.intel.com>, Kernel development list <linux-kernel@...r.kernel.org>, Laurent Pinchart <laurent.pinchart@...asonboard.com>, Oliver Neukum <oneukum@...e.com>, Johan Hovold <johan@...nel.org>, Michal Nazarewicz <mina86@...a86.com>, Vincent Pelletier <plr.vincent@...il.com>, Jerry Zhang <zhangjerry@...gle.com>, John Keeping <john@...anate.com>, Krzysztof Opasiak <k.opasiak@...sung.com>, Abdulhadi Mohamed <abdulahhadi2@...il.com>, Matthew Wilcox <willy@...ux.intel.com>, Janusz Dziedzic <januszx.dziedzic@...ux.intel.com> Subject: Re: Suspend to disk with usb connected fails to detect usb(reset) during resume On 11/08/2017 06:29 AM, Ivid Suvarna wrote: > On Tue, Nov 7, 2017 at 9:19 PM, Alan Stern <stern@...land.harvard.edu> wrote: >> On Tue, 7 Nov 2017, Ivid Suvarna wrote: >> >>> Hi, >>> >>> I am trying to support suspend to disk(hibernate) on Hikey with 4.4 >>> kernel. During suspend, I could see the usb devices getting reset and I >>> can access them properly. Message can be seen as below: >>> >>> usb 1-1: reset high-speed USB device number 2 using dwc2 >>> usb 1-1.2: reset high-speed USB device number 3 using dwc2 >>> usb 1-1.2.4: reset high-speed USB device number 4 using dwc2 >> >> You might start by asking why the devices need to be reset during >> suspend. I can't see any reason for doing this. >> >> Alan Stern >> > > Yes please. Could you explain as to why the usb needs to reset while > suspending? > This scenario is also observed in normal suspend to ram. > > And why the USB gets disconnected on resume from hibernation. > I checked the register dump of usb in /sys/kernel/debug and all > registers after resume have zero value. > Registers with zero value is indicative of a clock not getting turned on, at least that I have encountered with DWC2 on the SoCFPGA platform. Dinh
Powered by blists - more mailing lists