Hi Andrew, On Fri, 7 Nov 2014, Andrew Chew wrote: > > On Tue, 4 Nov 2014, Andrew Chew wrote: > > > > > Hello, Guennadi > > > > > > I was wondering if you can provide some advice as to how focuser vcm > > > devices would fit into the soc-camera framework. We have a raw sensor > > > (an IMX219) with an AD5823 VCM (it's just a simple I2C device) to > > > provide variable focus. > > > > > > I currently have the sensor and camera host driver instantiated via > > > device tree, following the guidelines in > > > Documentation/devicetree/bindings/media/video-interfaces.txt, by using > > > the of_graph stuff, and that all works fine. However, I'm not sure > > > what the proper way is to associate a focuser with that particular > > > image pipeline, and I couldn't find any examples to draw from. > > > > As discussed in an earlier thread [1], in principle soc-camera has support for > > attaching multiple subdevices to a camera-host (camera DMA engine) driver. > > In [2] you can see how I initially implemented DT for soc-camera, which also > > supported multiple subdevices. Beware, very old code. Some more > > comments are in [3]. > > > > Thanks > > Guennadi > > > > [1] http://www.spinics.net/lists/linux-sh/msg31436.html - see comment, > > following "Hm, I think, this isn't quite correct." > > > > [2] http://marc.info/?l=linux-sh&m=134875489304837&w=1 > > > > [3] https://www.mail-archive.com/linux-media@xxxxxxxxxxxxxxx/msg70514.html > > I think I get it, but just to clarify...currently, I'm going with the > patch in [1], and I currently have multiple subdevs (sensors) hooked up > and working with my soc-camera host driver. [2] was an alternate > implementation, right? (as in, I don't need it). No. [1] you don't need, it is already in the mainline, resp. its slightly updated version. I only quoted that thread for you above to read explanations about why that implementation didn't support multiple subdevices per host. To fix that support for multiple devices should be added to the current soc-camera mainline. To help with this task I quoted [2], which is my very early implementation attempt. [3] is just some more reading for general understanding. > So I understand that I can just hook up the focuser and flash subdevs to > the camera host via device tree, in the same exact way of using the > of_graph stuff to hook up the sensor subdev. My question is, is it then > left up to the camera host driver to make sense of which subdevs do > what? Or should/will there be a common mechanism to bind ports on a > camera host to a sensor, focuser, and flash under a common group which > makes up an image pipeline? Exactly, that's why you need multiple subdevices in groups, to have the whole pipeline probe only after all subdevices are available. Thanks Guennadi -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
