Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934653AbbGHKZB (ORCPT ); Wed, 8 Jul 2015 06:25:01 -0400 Received: from mail-wg0-f49.google.com ([74.125.82.49]:36745 "EHLO mail-wg0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934625AbbGHKYy (ORCPT ); Wed, 8 Jul 2015 06:24:54 -0400 From: Gabriele Mazzotta To: Jiri Kosina Cc: benjamin.tissoires@redhat.com, aduggan@synaptics.com, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] HID: i2c-hid: Call device suspend callback before disabling irq Date: Wed, 08 Jul 2015 12:24:50 +0200 Message-ID: <2307888.TWO9u1uPK9@xps13> In-Reply-To: References: <1436299082-3526-1-git-send-email-gabriele.mzt@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1652 Lines: 41 On Tuesday 07 July 2015 22:49:30 Jiri Kosina wrote: > On Tue, 7 Jul 2015, Gabriele Mazzotta wrote: > > > The irq is most likely required by the suspend callback, so disable it > > only after the callback had been executed. > > It would be nice to have a more verbose changelog here -- i.e. why we want > to do such change and what could go wrong if IRQ is disabled too early > (i.e. what bug is this exactly fixing). > > > > > Signed-off-by: Gabriele Mazzotta > > I'd see this as a 4.2 material still. Please let me know if you'd rather > want to wait for 4.3. > > Thanks, I would have given an instance showing the problem, but AFAIK there isn't one yet as there are no drivers doing something with IRQs on suspend. I encounterd problems while modifying hid-rmi.c, but since the changes aren't there yet, I couldn't mention them. Still, I could have written something better. What about something like the following? I can resend the patch with the new message if it's OK. --- i2c-hid takes care of requesting and handling IRQs for HID devices which in turns might expect them to be always active when working in normal conditions. Hence, disabling IRQs before calling the suspend callbacks can potentially cause problems since device drivers might try to perform operations needing them. Fix this by disabling IRQs only after the suspend callbacks had been executed. -- 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/