From mboxrd@z Thu Jan 1 00:00:00 1970 From: Markus Armbruster Subject: Re: RFC: drop frontend support for relative pointer Date: Mon, 12 Oct 2009 22:42:09 +0200 Message-ID: <87d44ss5su.fsf@pike.pond.sub.org> References: <87vdirw2d8.fsf@pike.pond.sub.org> <20091007200124.GD2270@redhat.com> <87skduoxbo.fsf@pike.pond.sub.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: (Jean Guyader's message of "Mon\, 12 Oct 2009 19\:31\:52 +0100") List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jean Guyader Cc: "xen-devel@lists.xensource.com" , "Daniel P. Berrange" , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org Jean Guyader writes: > 2009/10/12 Jean Guyader : >> 2009/10/8 Markus Armbruster : >>> Stefano Stabellini writes: >>> >>>> On Wed, 7 Oct 2009, Daniel P. Berrange wrote: >>>>> That's good to know - stubdom was one area I was concerned about. To = the >>>>> best of my knowledge the only backend that ever sent relative mouse e= vents >>>>> was the old PVFB we had in Fedora 6 which was the original code before >>>>> the eventual merge into official xen-devel trees. So official repos h= ave >>>>> always defaulted to absolute mode. =C2=A0Hopefully no one out there h= as gone >>>>> and re-implemented the PVFB backend in any other fork of Xen and drop= ped >>>>> ABS mode or made REL the default ??? >>>>> >>>>> IMHO if ABS mode is able to work correctly, then there's absolutely no >>>>> benefit in having a REL mode at all, so its best deleted / removed. >>>> >>>> I guess keeping around unused code doesn't make much sense but I was j= ust >>>> being cautious, given that for example XCI is currently using relative >>>> coordinates so they are not dead just yet. >>> >>> Just to avoid misunderstandings: >>> >>> * Does XCI set feature-abs-pointer in xenstore? >>> >>> * If it does, does it read request-abs-pointer from xenstore? >>> >>> * Under what circumstances (if any) does it send XENKBD_TYPE_MOTION, and >>> =C2=A0under what circumstances (if any) does it send XENKBD_TYPE_POS? >>> >> >> Hi, >> >> I just checked and we have feature-abs-pointer and request-abs-pointer >> set to 1 xenstore. >> The function we use to inject mouse/keyboard event in the guess is >> kbd_mouse_event and it works with xenkbd. >> > > I checked into the code and we force xenkb to use relative coordinates. > We use that because in XCI the hardware mouse on the host is generally > setup to send relative coordinates, and we do a 1 to 1 map for the > mouse/keyboard > event. Thanks for your help. To sum up: * The XCI backend advertizes absolute pointers (feature-abs-pointer set in xenstore) * The frontend asks for it (request-abs-pointer set in xenstore) * Regardless, the XCI backend sends only relative coordinates (event type XENKBD_TYPE_POS). Correct? If yes, then this works more by accident than by design :) By setting feature-abs-pointer, the backend offers absolute events. Reneging on this offer after the frontend accepted it is a bug. What now? Could XCI upgrade to absolute? If not, could it at least stop offering feature-abs-pointer?