From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chase Douglas Subject: Re: Magic trackpad issues on 3.0 Date: Tue, 16 Aug 2011 11:48:30 -0700 Message-ID: <4E4ABB7E.8020505@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-vx0-f174.google.com ([209.85.220.174]:54127 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753129Ab1HPSsg (ORCPT ); Tue, 16 Aug 2011 14:48:36 -0400 Received: by vxi9 with SMTP id 9so188591vxi.19 for ; Tue, 16 Aug 2011 11:48:36 -0700 (PDT) In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Michael Poole Cc: Jaikumar Ganesh , linux-input@vger.kernel.org, jkosina@suse.cz On 08/15/2011 08:45 PM, Michael Poole wrote: > On Mon, Aug 15, 2011 at 10:40 PM, Jaikumar Ganesh wrote: >> Hi Michael: >> >> On Mon, Aug 15, 2011 at 7:03 PM, Michael Poole wrote: >>> On Mon, Aug 15, 2011 at 4:18 PM, Jaikumar Ganesh wrote: >>>> Folks, >>>> This is with regard to the issue: >>>> >>>> http://www.spinics.net/lists/linux-input/msg15334.html >>>> >>>> As mentioned in that thread we were ignoring the EIO return value earlier. >>>> >>>> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=c3a4924565e2eecf2539871abd123d35be6d76d5 >>>> >>>> reverted the commit back, because >>>> >>>> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=7f4f0572df6c8eaa6a587bc212b0806ff37380dd >>>> fixed the issue with the Bluetooth stack with 1.1 Bluetooth devices. >>>> >>>> However, I am seeing the same problem with an Apple Trackpad which is >>>> 2.0 Bluetooth device. It worked fine before because we were ignoring >>>> the EIO. >>>> >>>> The Error code is the same as mentioned in the thread above: Invalid >>>> Report ID while calling the Set Feature Report call. >>>> >>>> So to the driver authors: >>>> >>>> In magicmouse_probe function, the report id is set to d7. __u8 >>>> feature[] = { 0xd7, 0x01 }; >>>> >>>> Is it guaranteed that all Apple devices will have 0xd7 as the report >>>> Id. Why are we not reading the report ID from the report descriptor >>>> since its an optional feature ? >>> >>> The report descriptor does not include that feature report. There are >>> a number of commands for Apple's Magic Mouse and Magic Trackpad that >>> are not listed in the standard HID descriptor. >> >> Has Apple documented this anywhere ? Will every Apple trackpad support it ? >> Should we continue to have some fail-safe like the EIO fix ? > > Hi Jaikumar, > > I do not believe Apple has documented the protocol anywhere, or makes > any guarantee of compatibility in future devices -- although forward > compatibility makes sense in terms of the installed base of drivers, > and I suspect any devices that use a different protocol would get > different device IDs. > > I think the EIO fix should stay. I just started to notice this issue last week. The Ubuntu 3.0.0-7 kernel (the -# part is an ubuntu suffix) seems to work fine, but 3.0.0-8 does not. I would guess a -stable patch is causing a regression, but the diff stat from 3.0 to 3.0.1 doesn't show anything related to input, hid, or bluetooth. -- Chase