From: Matthew Garrett Subject: Refcounting GPEs Date: Tue, 18 Aug 2009 23:32:28 +0100 Message-ID: <20090818223228.GA2773@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from cavan.codon.org.uk ([93.93.128.6]:56254 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751625AbZHRWce (ORCPT ); Tue, 18 Aug 2009 18:32:34 -0400 Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Moore, Robert" Cc: "linux-acpi@vger.kernel.org" Implementing runtime PM for PCI requires ensuring that device GPEs are enabled for runtime. This is made awkward by the fact that multiple PCI and ACPI devices may use the same GPE, so it's necessary to track how many devices currently want the GPE to be enabled. This would seem to imply some sort of refcounting, but I can't see an especially clean way to implement this in the current code. Does anyone have any preferences for what this interface should look like? -- Matthew Garrett | mjg59@srcf.ucam.org