From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: [linux-pm] [patch update 2 fix] PM: Introduce core framework for run-time PM of I/O devices Date: Mon, 22 Jun 2009 10:15:41 +0200 Message-ID: <200906221015.42805.oliver@neukum.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from smtp-out003.kontent.com ([81.88.40.217]:37398 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752219AbZFVIPk convert rfc822-to-8bit (ORCPT ); Mon, 22 Jun 2009 04:15:40 -0400 In-Reply-To: Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Magnus Damm Cc: Alan Stern , "Rafael J. Wysocki" , Greg KH , LKML , ACPI Devel Maling List , Linux-pm mailing list , Ingo Molnar Am Montag, 22. Juni 2009 08:20:43 schrieb Magnus Damm: > I'd like to call pm_request_suspend() from interrupt context. I don't > depend on it, but being able to perform runtime suspend directly from > the ISR would be convenient from a device driver POV. I'm not sure if > that should result in bus/device ->runtime_suspend() calls from > interrupt context though. > > In my case the bus specific code for ->runtime_suspend() may just > decrease the usage count of the powerdomain but refrain from calling > the device ->runtime_suspend() callbacks until all devices in the > powerdomain have been suspended. The bus/device runtime suspend > callbacks do not need to be executed from interrupt context. Just > noting that the device is idle is enough at interrupt time. This could > be handled by generic code IMO. >>From practical experience doing USB power management I can tell you that requesting suspension from interrupt makes things a lot easier for driver writers. Regards Oliver