On 2/22/10 5:01 PM, Rodolfo Giometti wrote: > On Fri, Feb 19, 2010 at 08:36:38PM +0100, Guennadi Liakhovetski wrote: >> On Fri, 19 Feb 2010, Rodolfo Giometti wrote: >> >>> Hello, >>> >>> on my pxa27x based board I have a adv7180 connected with the CIF >>> interface. Due this fact I'm going to use the pxa_camera.c driver >>> which in turn registers a soc_camera_host. >>> >>> In the latest kernel I found your driver for the ADV7180, but it >>> registers the chip as a v4l sub device. >>> >>> I suppose these two interfaces are not compatible, aren't they? >> >> Congratulations! Thereby you're in a position to develop the first >> v4l2-subdev / soc-camera universal driver;) The answer to this your >> question is - they are... kinda. This means - yes, soc-camera is also >> using the v4l2-subdev API, but - with a couple of additions. Basically, >> there are two things you have to change in the adv7180 driver to make it >> compatible with soc-camera - (1) add bus-configuration methods, even if >> they don't do much (see .query_bus_param() and .set_bus_param() methods >> from struct soc_camera_ops), and (2) migrate the driver to the mediabus >> API. The latter one requires some care - in principle, mediabus should be >> the future API to negotiate parameters on the video bus between bridges >> (in your case PXA CIF) and clients, but for you this means you also have >> to migrate any other bridge drivers in the mainline to that API, and, if >> they also interface to some other subdevices - those too, and if those can >> also work with other bridges - those too...;) But, I think, that chain >> will terminate quite soon, in fact, I cannot find any users of that driver >> currently in the mainline, Richard? >> >>> In this situation, should I write a new driver for the >>> soc_camera_device? Which is The-Right-Thing(TM) to do? :) >> >> Please, have a look and try to convert the driver as described above. All >> the APIs and a few examples are in the mainline, so, you should have >> enough copy-paste sources;) Ask on the list (with me on cc) if anything is >> still unclear. > > Thanks for your quick answer! :) > > What I still don't understand is if should I move the driver form > v4l2-subdev to a soc_camera device or trying to support both API... > > It seems to me that the driver is not used by any machines into > mainline so if soc-camera is also using the v4l2-subdev API but with a > couple of additions I suppose I can move it to soc_camera API... > > Is that right? We use it as a subdev to a driver not yet committed from us. So I think you should extend it, not move it. --Richard -- 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
