From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Dmitry Torokhov" Subject: Re: FF layer restrictions [Was: [PATCH 1/1] Input: add sensable phantom driver] Date: Fri, 30 Mar 2007 12:46:41 -0400 Message-ID: References: <2460126662758025813@fi.muni.cz> <460983D6.7070409@gmail.com> <38b3b7c0703271434u2fddc4d1jc2b9af097e9c95b2@mail.gmail.com> <200703272308.34441.dtor@insightbb.com> <460AE933.6010209@gmail.com> <460AEA8C.2050102@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <460AEA8C.2050102@gmail.com> Content-Disposition: inline Sender: owner-linux-input@atrey.karlin.mff.cuni.cz List-Help: List-Owner: List-Post: List-Unsubscribe: To: Jiri Slaby Cc: johann deneux , "=?ISO-8859-1?Q?\"STenyaK_(Bruno_Gonz=E1lez)\"?=" , Anssi Hannula , Linux kernel mailing list , linux-input@atrey.karlin.mff.cuni.cz List-Id: linux-input@vger.kernel.org On 3/28/07, Jiri Slaby wrote: > Jiri Slaby napsal(a): > > Dmitry Torokhov napsal(a): > >> On Tuesday 27 March 2007 17:34, johann deneux wrote: > >>> What about adding a member to ff_effect which would be the number of the motor? > >>> We can't change the layout of ff_effect too much though, so we have to > >>> find unused bits and put them to work. > >>> > >>> For instance, we could replace > >>> > >>> __u16 type; > >>> > >>> by > >>> > >>> __u8 motor; > >>> __u8 type; > >>> > >> Splitting type field seems to be a good idea. > > > > Maybe stupid question, but what about endianness + backward compatibility? > > If we split it into motor,type sequence, it would break LE (untouched BE), > > if we do type,motor, it is OK for LE (broken BE). > > Aha, and the question is: do > > #ifdef __BIG_ENDIAN > #else > #endif > > ? > I am so tempted to say "screw BE, there is not many users of FF layer" but I am afraid we will have to do that #ifdef-fu. -- Dmitry