From mboxrd@z Thu Jan 1 00:00:00 1970 From: valentin.longchamp@epfl.ch (Valentin Longchamp) Date: Tue, 03 Nov 2009 12:31:01 +0100 Subject: [PATCH 5/6] mx31moboard: camera support In-Reply-To: <4AE855E4.1040705@epfl.ch> References: <1255599780-12948-1-git-send-email-valentin.longchamp@epfl.ch> <1255599780-12948-2-git-send-email-valentin.longchamp@epfl.ch> <1255599780-12948-3-git-send-email-valentin.longchamp@epfl.ch> <1255599780-12948-4-git-send-email-valentin.longchamp@epfl.ch> <1255599780-12948-5-git-send-email-valentin.longchamp@epfl.ch> <1255599780-12948-6-git-send-email-valentin.longchamp@epfl.ch> <4ADC96A9.3090403@epfl.ch> <20091020080941.GN8818@pengutronix.de> <4ADF40BC.4090801@epfl.ch> <4AE855E4.1040705@epfl.ch> Message-ID: <4AF01475.1010704@epfl.ch> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Guennadi, Valentin Longchamp wrote: > Guennadi Liakhovetski wrote: > >> 3. to support switching inputs, significant modifications to soc_camera.c >> would be required. I read Nate's argument before, that as long as clients >> can only be accessed one at a time, this should be presented by multiple >> inputs rather than multiple device nodes. Somebody else from the V4L folk >> has also confirmed this opinion. In principle I don't feel strongly either >> way. But currently soc-camera uses a one i2c client to one device node >> model, and I'm somewhat reluctant to change this before we're done with >> the v4l2-subdev conversion. >> > > Sure, one step at a time. So for now the switching is not possible with > soc_camera. > > My problem is that both cameras have the same I2C address since they are > the same. > > Would I need to declare 2 i2c_device with the same address (I'm not sure > it would even work ...) used by two _client_ platform_devices or would I > have to have the two platform devices pointing to the same i2c_device ? > I've finally had time to test all this. My current problem with registering the two cameras is that they both have the same i2c address, and soc_camera calls v4l2_i2c_new_subdev_board where in my case the same address on the same i2c tries to be registered and of course fails. We would need a way in soc_camera not to register a new i2c client for device but use an existing one (but that's what you don't want to change for now as you state it in your above last sentence). I just want to point this out once more so that you know there is interest about this for the next soc_camera works. So my current solution for mainline inclusion is to register only one camera device node without taking care of the cam mux for now. Val -- Valentin Longchamp, PhD Student, EPFL-STI-LSRO1 valentin.longchamp at epfl.ch, Phone: +41216937827 http://people.epfl.ch/valentin.longchamp MEA3485, Station 9, CH-1015 Lausanne