Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753112AbdLAOeH (ORCPT ); Fri, 1 Dec 2017 09:34:07 -0500 Received: from mail-ot0-f196.google.com ([74.125.82.196]:36783 "EHLO mail-ot0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753018AbdLAOeF (ORCPT ); Fri, 1 Dec 2017 09:34:05 -0500 X-Google-Smtp-Source: AGs4zMbzuEFRLZQqz9GQKT9/HVRMQOnsYIXa5iYsqJyDkGtlJ7V5zO/5ffraQgNcciZZ0MPWkdrgjENXWJz9QfvJBO4= MIME-Version: 1.0 In-Reply-To: <20171201141801.GA20189@wunner.de> References: <1532136.s6buYvDjaS@aspire.rjw.lan> <20171201141801.GA20189@wunner.de> From: "Rafael J. Wysocki" Date: Fri, 1 Dec 2017 15:34:04 +0100 X-Google-Sender-Auth: iQ1BmnFyssH8ZPR5DMrJbNnggK4 Message-ID: Subject: Re: [PATCH] PM / runtime: Fix handling of suppliers with disabled runtime PM To: Lukas Wunner Cc: "Rafael J. Wysocki" , Linux PM , LKML , Adrian Hunter , Greg Kroah-Hartman Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1861 Lines: 43 On Fri, Dec 1, 2017 at 3:18 PM, Lukas Wunner wrote: > On Fri, Dec 01, 2017 at 02:58:34PM +0100, Rafael J. Wysocki wrote: >> From: Rafael J. Wysocki >> >> Prevent rpm_get_suppliers() from returning an error code if runtime >> PM is disabled for one or more of the supplier devices it wants to >> runtime-resume, so as to make runtime PM work for devices with links >> to suppliers that don't use runtime PM (such links may be created >> during device enumeration even before it is known whether or not >> runtime PM will be enabled for the devices in question, for example). >> >> Reported-by: Adrian Hunter >> Fixes: 21d5c57b3726 (PM / runtime: Use device links) >> Signed-off-by: Rafael J. Wysocki >> --- >> drivers/base/power/runtime.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> Index: linux-pm/drivers/base/power/runtime.c >> =================================================================== >> --- linux-pm.orig/drivers/base/power/runtime.c >> +++ linux-pm/drivers/base/power/runtime.c >> @@ -276,7 +276,8 @@ static int rpm_get_suppliers(struct devi >> continue; >> >> retval = pm_runtime_get_sync(link->supplier); >> - if (retval < 0) { >> + /* Ignore suppliers with disabled runtime PM. */ >> + if (retval < 0 && retval != -EACCES) { >> pm_runtime_put_noidle(link->supplier); >> return retval; >> } >> > > You could alternatively call pm_runtime_get_sync() under the condition > link->supplier->power.disable_depth > 0 but then the usage_count wouldn't > be incremented and I guess we want that in case runtime PM is only > temporarily disabled and later enabled, right? Right. Thanks, Rafael