From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755884AbbAWQxJ (ORCPT ); Fri, 23 Jan 2015 11:53:09 -0500 Received: from butterbrot.org ([176.9.106.16]:57978 "EHLO butterbrot.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753878AbbAWQxH (ORCPT ); Fri, 23 Jan 2015 11:53:07 -0500 X-Greylist: delayed 396 seconds by postgrey-1.27 at vger.kernel.org; Fri, 23 Jan 2015 11:53:07 EST Message-ID: <54C27AE4.4020702@butterbrot.org> Date: Fri, 23 Jan 2015 17:46:28 +0100 From: Florian Echtler User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: "Baluta, Teodora" , Sylwester Nawrocki , Jonathan Cameron CC: Mauro Carvalho Chehab , Lars-Peter Clausen , Linux Kernel Mailing List , linux-iio , LMML , Hans Verkuil Subject: Re: [RFC PATCH 0/3] Introduce IIO interface for fingerprint sensors References: <1417698017-13835-1-git-send-email-teodora.baluta@intel.com> <5481153B.4070609@kernel.org> <1418047828.18463.10.camel@bebop> <54930604.1020607@metafoo.de> <549D42BD.1050901@kernel.org> <1421255642.31900.4.camel@bebop> <54B7FAF2.8080207@samsung.com> In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="nS1pCTG5i2HEopfJ57PrmSaElcWIb8gne" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --nS1pCTG5i2HEopfJ57PrmSaElcWIb8gne Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hello Teodora, On 23.01.2015 14:05, Baluta, Teodora wrote: > The fingerprint sensor acts more like a scanner device, so the > closest type is the V4L2_CAP_VIDEO_CAPTURE. However, this is not a > perfect match because the driver only sends an image, once, when > triggered. Would it be a better alternative to define a new > capability type? Or it would be acceptable to simply have a video > device with no frame buffer or frame rate and the user space > application to read from the character device /dev/videoX? Sorry if I jump in here right in the middle of this discussion, but some time ago, I wrote a fingerprint sensor driver for the Siemens ID Mouse (still part of the kernel AFAICT) which acts as a misc device and just creates a character device node that can be used to directly read a PGM file. Maybe this would be a slightly simpler approach than pulling in all the streaming-optimized features of V4L2? Best, Florian --=20 SENT FROM MY DEC VT50 TERMINAL --nS1pCTG5i2HEopfJ57PrmSaElcWIb8gne Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlTCeuQACgkQ7CzyshGvatjWsgCdHyNxoUEdkJhMapuv1VzNOWrC MPoAoPlq+IDgg2aCbLrxWFpQWI7KQgk1 =R3Ri -----END PGP SIGNATURE----- --nS1pCTG5i2HEopfJ57PrmSaElcWIb8gne--