From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751470AbdBSRRC (ORCPT ); Sun, 19 Feb 2017 12:17:02 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:39426 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750893AbdBSRQ5 (ORCPT ); Sun, 19 Feb 2017 12:16:57 -0500 Date: Sun, 19 Feb 2017 18:15:18 +0100 From: Pavel Machek To: "H. Nikolaus Schaller" Cc: Dmitry Torokhov , Sebastian Reichel , Mark Rutland , =?iso-8859-1?Q?Beno=EEt?= Cousson , Tony Lindgren , Russell King , Arnd Bergmann , Michael Welling , Mika =?iso-8859-1?Q?Penttil=E4?= , Javier Martinez Canillas , Igor Grinberg , "Andrew F. Davis" , Mark Brown , Jonathan Cameron , Rob Herring , Alexander Stein , Eric Engestrom , Hans de Goede , Benjamin Tissoires , Petr Cvek , Mauro Carvalho Chehab , Hans Verkuil , Nick Dyer , Siebren Vroegindeweij , Michel Verlaan , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, letux-kernel@openphoenux.org, linux-iio@vger.kernel.org, kernel@pyra-handheld.com, Aaro Koskinen , Pali =?iso-8859-1?Q?Roh=E1r?= , Andrey Gelman , Haibo Chen Subject: Re: [PATCH v9 1/8] drivers:input:tsc2007: add new common binding names, pre-calibration, flipping and rotation Message-ID: <20170219171518.GA12833@amd> References: <1F6355E1-A5E3-41A6-908F-619A15581BEF@goldelico.com> <20170217204041.GE13050@dtor-ws> <20170218091526.GC8937@amd> <61F3C580-4BF2-4EE6-9DEC-FB8634434EC0@goldelico.com> <20170218180811.GB9377@amd> <27287BC5-E4E2-4F50-B140-C74D3CADED5B@goldelico.com> <20170218225435.GA4693@amd> <20170219141715.GA7159@amd> <05F3816F-46E6-4BC2-9E2E-F20E645F7197@goldelico.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="nFreZHaLTZJo0R7j" Content-Disposition: inline In-Reply-To: <05F3816F-46E6-4BC2-9E2E-F20E645F7197@goldelico.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --nFreZHaLTZJo0R7j Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > Solve it properly. That means passing calibration > > data from kernel to userland. >=20 > As written before, the really proper solution would be to provide floating > or fixed point subpixel input events. Not arbitrarily scaling up in kernel > and leaving downscaling to user space (where everybody can make it > worse). That has no advantages, and floating point in kernel is hard. Also you'd either have to invent new interface, or you'd break touchscreen for people that already have their touchscreens calibrated. Just pass calibration data to userland. > But I don't think it is worth implementing subpixel touch events for real > world devices due to the jitter I mentioned. Yes, that's not really proper solution, that just overengineered. Not worth implementing. Pass calibration data to userland. Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --nFreZHaLTZJo0R7j Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlip0qYACgkQMOfwapXb+vLiFQCeKjGeHS0AZN0qawWIgzFobC8P 2goAnifAx3O1l1Y2ea59Q3l+ZqDCYqOF =vz/X -----END PGP SIGNATURE----- --nFreZHaLTZJo0R7j--