From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: as3645a flash userland interface Date: Thu, 14 Sep 2017 12:07:18 +0200 Message-ID: <20170914100718.GA3843@amd> References: <20170912084236.1154-1-sakari.ailus@linux.intel.com> <20170912084236.1154-25-sakari.ailus@linux.intel.com> <20170912103628.GB27117@amd> <7b679cb3-ce58-e1d1-60bf-995896bf46eb@gmail.com> <20170912215529.GA17218@amd> <21824758-28a1-7007-6db5-86a900025d14@gmail.com> <4bf12e8e-beff-0199-cdee-4a52ebe7cdaf@samsung.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="sm4nu43k4a2Rpi4c" Return-path: Content-Disposition: inline In-Reply-To: <4bf12e8e-beff-0199-cdee-4a52ebe7cdaf-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sylwester Nawrocki Cc: Jacek Anaszewski , Sakari Ailus , linux-leds-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, niklas.soderlund-1zkq55x86MTxsAP9Fp7wbw@public.gmane.org, robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, hverkuil-qWit8jRvyhVmR6Xm/wNWPw@public.gmane.org, laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org List-Id: devicetree@vger.kernel.org --sm4nu43k4a2Rpi4c Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > >>>>What directory are the flash controls in? > >>>> > >>>>/sys/class/leds/led-controller:flash ? > >>>> > >>>>Could we arrange for something less generic, like > >>>> > >>>>/sys/class/leds/main-camera:flash ? > >>> > >>>I'd rather avoid overcomplicating this. LED class device name pattern > >>>is well defined to devicename:colour:function > >>>(see Documentation/leds/leds-class.txt, "LED Device Naming" section). > >>> > >>>In this case "flash" in place of the "function" segment makes the > >>>things clear enough I suppose. > >> > >>It does not. > >> > >>Phones usually have two cameras, front and back, and these days both > >>cameras have their flash. > >> > >>And poor userspace flashlight application can not know if as3645 > >>drivers front LED or back LED. Thus, I'd set devicename to > >>front-camera or main-camera -- because that's what it is associated > >>with. Userspace does not care what hardware drives the LED, but needs > >>to know if it is front or back camera. > > > >The name of a LED flash class device isn't fixed and is derived > >from DT label property. Name in the example of some DT bindings > >will not force people to apply similar pattern for the other > >drivers and even for the related one. No worry about having > >to keep anything forever basing on that. >=20 > Isn't the V4L2 subdev/Media Controller API supposed to provide means > for associating flash LEDs with camera sensors? You seem to be insisting > on using the sysfs leds interface for that, which is not a primary > interface for camera flash AFAICT. a) subdev/media controller API currently does not provide such means. b) if we have /sys/class/leds interface to userland, it should be useful. c) having flashlight application going through media controller API is a bad joke. Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --sm4nu43k4a2Rpi4c Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlm6VNYACgkQMOfwapXb+vIu4wCfcERX0wrdAVt5HeogfBdgba5W SnIAnReSCKgIbWpDTsfX3/BRFNgx6t/C =MD5V -----END PGP SIGNATURE----- --sm4nu43k4a2Rpi4c-- -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html