From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id B5C359A9 for ; Thu, 28 Jul 2016 11:58:53 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 73602133 for ; Thu, 28 Jul 2016 11:58:53 +0000 (UTC) Date: Thu, 28 Jul 2016 08:58:46 -0300 From: Mauro Carvalho Chehab To: Jonathan Cameron Message-ID: <20160728085846.63971233@recife.lan> In-Reply-To: <5222c3bb-d6b7-0ccc-bf9e-becf5046a37a@kernel.org> References: <5222c3bb-d6b7-0ccc-bf9e-becf5046a37a@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Zhang Rui , Rob Herring , ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [TECH TOPIC] Sensors and similar - subsystem interactions, divisions, bindings etc. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Em Wed, 20 Jul 2016 22:18:11 +0100 Jonathan Cameron escreveu: > Hi All, > > This topic would be around the way the various subsystems interact, in the > rough area of 'sensors' (I haven't yet had much of an issue with subsystem > crossing with output devices but maybe that's just over the next hill!) Yeah, there is a gray area here as devices become more complex. So, I'm interested on such topic. > Scope may well be wider but includes: > * input (some of it) > * hwmon > * iio > * comedi(?) > * thermal > * power/battery > * gpio - the blur between gpios and beaglescope / PLC type I/O. > * v4l - when does a device jump from being a multi pixel thermopile > to a thermal camera? Smart fingerprint scanners etc. Gesture recognition > sensors (effectively 9ish pixel cameras) For devices that provide images somehow, I'd say that the best would be to implement them as via the V4L2 API. We'll likely need to discuss it case by case, specially for early cross-subsystem drivers, though, as it is not trivial to identify the subsystem boundaries, and sometimes multiple APIs from different subsystems is needed. Also, it is not clear where such drivers would fit at the Kernel tree. One interesting case is an input device driver with multi-finger support (drivers/input/touchscreen/sur40.c). I suspect we'll have more cases like that over time. > * Lots of random things we haven't seen yet. Thanks, Mauro