From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Fu, Zhonghui" Subject: Re: [PATCH v2] hid: enable hid device to suspend/resume asynchronously Date: Mon, 23 Nov 2015 14:03:33 +0800 Message-ID: <5652AC35.5030302@linux.intel.com> References: <560392E7.1030207@linux.intel.com> <5649F3A3.8080007@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mga01.intel.com ([192.55.52.88]:44161 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752139AbbKWGDg (ORCPT ); Mon, 23 Nov 2015 01:03:36 -0500 In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Jiri Kosina Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org On 11/16/2015 11:26 PM, Jiri Kosina wrote: > On Mon, 16 Nov 2015, Fu, Zhonghui wrote: > >> Hi Jiri, >> >> Any comments about this patch? >> >> After enabling the HID devices suspend/resume asynchronously on ASUS >> T100TA(Baytrail-T platform), the system suspend-to-idle/resume time is >> reduced about 20ms. Although this improvement is not very significant. >> But, if the suspend/resume operation of HID devices is very >> time-consuming on some other platforms, this patch can improve >> significantly system suspend/resume speed on these platforms. > Hi, > > I don't think the question I've raised at > > http://lkml.kernel.org/r/alpine.LNX.2.00.1509251404130.30132@pobox.suse.cz > > has ever been answered or at least discussed ... ? Sorry for missing this mail. At present, the file(/sys/.../power/async) can be used to enable one device suspend/resume asynchronously. My patch only changes the default value of this file from "disabled" to "enabled". The sole difference of asynchronous suspend/resume mode is that the suspend/resume operation of one device is carried out in a separate kernel thread, and PM core ensures all related dependency. I have verified this patch on some platforms, such as ASUS T100TA. Actually, many other devices have used this feature for a long time. Thanks, Zhonghui >