Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268581AbUIXIXv (ORCPT ); Fri, 24 Sep 2004 04:23:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268582AbUIXIXv (ORCPT ); Fri, 24 Sep 2004 04:23:51 -0400 Received: from gate.crashing.org ([63.228.1.57]:19684 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S268581AbUIXIXs (ORCPT ); Fri, 24 Sep 2004 04:23:48 -0400 Subject: Re: suspend/resume support for driver requires an external firmware From: Benjamin Herrenschmidt To: Patrick Mochel Cc: "Zhu, Yi" , Linux Kernel Mailing List In-Reply-To: References: Content-Type: text/plain Message-Id: <1096014170.30196.52.camel@gaston> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Fri, 24 Sep 2004 18:22:52 +1000 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1381 Lines: 31 > We talked about this in Ottawa a few months ago, and I think this is the > right approach. Note though, that I think it needs to be more complete: > > - There needs to be restore_state() to be symmetic. > - There needs to be the proper failure recovery > If save_state() or suspend() fails, every device that has had their > state saved needs to be restored. > - It needs to be called for all power management requests. > - The PCI implementation should call pci_save_state() in it, instead of in > ->suspend(). > > It would be great if you could add these things. Otherwise, I'll add it to > my TODO list.. Additionally, for devices like the above that need either to rely on userland for firmware download or to allocate large amounts of memory for firmware backup/restore, I think we need to revive the pre-suspend and post-resume notifiers ... Of course, if a device that needs userland to reload a firmware is on the swap patch, then we have a chicken & egg problem, but there is no easy solution for that one, unless the driver uses the pre-suspend callback to pre-load the firmware that it will need for resume Ben. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/