Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753197AbaKZO2A (ORCPT ); Wed, 26 Nov 2014 09:28:00 -0500 Received: from cantor2.suse.de ([195.135.220.15]:42564 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752981AbaKZO17 (ORCPT ); Wed, 26 Nov 2014 09:27:59 -0500 Message-ID: <1417012077.5928.11.camel@linux-0dmf.site> Subject: Re: bluetooth related firmware loader spew on resume. From: Oliver Neukum To: Takashi Iwai Cc: Marcel Holtmann , Dave Jones , Linux Kernel , pgynther@google.com, linux-bluetooth@vger.kernel.org Date: Wed, 26 Nov 2014 15:27:57 +0100 In-Reply-To: References: <20141111181228.GA27815@redhat.com> <1416996623.3171.7.camel@linux-0dmf.site> <0E1D95E7-64D2-4BEA-AFAA-4B119838F24E@holtmann.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2014-11-26 at 15:12 +0100, Takashi Iwai wrote: > At Wed, 26 Nov 2014 23:05:20 +0900, > Marcel Holtmann wrote: > > > > Hi Oliver, > > > > >> In order to paper over this, we may also remember the failing firmware > > >> and avoid loading it. This might be an easer way than the endless > > >> fight against UMH race... > > > > > > > > > the full fix would be to implement reset_resume() for btusb. > > > It seems to me that setup() should be split in two methods, > > > one to request the firmware from user space and the second > > > to transfer it to the device. reset_resume() would just need > > > to repeat the second operation. > > > > so when you do hci_register_dev, then hdev->setup is only called once. I really mean only once per lifetime of the hci_dev. So you would need to unregister the hci_dev first before hdev->setup will ever be called again. So I am not sure this is actually the problem here. The problem here is entirely within request_firmware() unless of course we run through the USB probe handlers again. Which I do not see happening here. > > > > And we have hdev->setup this way since normally the Bluetooth devices keep their firmware patches and not forget about them and suspend-resume cycles. If the USB device of course jumps of the bus during it then all bets are off anyway. > > Usually you can avoid unnecessary rebinding when you provide a proper > reset_resume callback. I guess that's what Oliver suggested. Yes, but even in reset_resume() you would need to redo the setup part, as the device lost power. The basic problem of requesting the firmware wouldn't be solved. Regards Oliver -- 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/