From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Stern Subject: Re: [RFC PATCH] scsi: sr: support runtime pm Date: Mon, 21 Jan 2013 11:59:06 -0500 (EST) Message-ID: References: <20130121093707.GB11010@aaronlu.sh.intel.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Received: from netrider.rowland.org ([192.131.102.5]:39895 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752638Ab3AUQ7H (ORCPT ); Mon, 21 Jan 2013 11:59:07 -0500 In-Reply-To: <20130121093707.GB11010@aaronlu.sh.intel.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Aaron Lu Cc: Oliver Neukum , Julian Calaby , James Bottomley , Jeff Garzik , "Rafael J. Wysocki" , Tejun Heo , Aaron Lu , Jeff Wu , linux-ide@vger.kernel.org, linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org, linux-acpi@vger.kernel.org On Mon, 21 Jan 2013, Aaron Lu wrote: > On Sat, Jan 19, 2013 at 01:46:15PM -0500, Alan Stern wrote: > > On Sat, 19 Jan 2013, Aaron Lu wrote: > > > I don't think we should drop such support. > > > And the safest way to avoid such break is we refine the suspend > > > condition for ODD, and using what ZPODD defined condition isn't that > > > bad to me: > > > - for tray type, no media inside and tray close; > > > - for slot type, no media inside. > > > While whether tray is closed or not may not be that important, but at > > > least we should make sure there is no media inside. > > > > > > Thoughts? > > > > That sounds reasonable to me, at least as a first step. If people want > > their CD drive to suspend, they can eject the disc. > > Here is an updated patch to address the problem, please review, thanks. > > Changes to v13: > - Add PM get/put pair functions to all the block device operation > functions; Move the existing PM get/put pair functions in > sr_check_events to sr_block_check_events; > - Add sr_runtime_suspend, it will check if there is media inside and if > yes, avoid suspend. > > From 378bf55810a1118ede481f45132b5c39af891d23 Mon Sep 17 00:00:00 2001 > From: Aaron Lu > Date: Wed, 26 Sep 2012 15:14:56 +0800 > Subject: [RFC PATCH] scsi: sr: support runtime pm > > This patch adds runtime pm support for sr. > > It did this by increasing the runtime usage_count of the device when > its block device is accessed. And decreasing the runtime usage_count > of the device when the access is done. > > The idea is discussed here: > http://thread.gmane.org/gmane.linux.acpi.devel/55243/focus=52703 > and here: > http://thread.gmane.org/gmane.linux.ide/53665/focus=58836 > > Signed-off-by: Aaron Lu This looks good now. When you submit the patch, you might want to mention the restriction about no media being present in the changelog entry. Acked-by: Alan Stern