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? Ciao, Rodolfo -- GNU/Linux Solutions e-mail: giometti@xxxxxxxxxxxx Linux Device Driver giometti@xxxxxxxx Embedded Systems phone: +39 349 2432127 UNIX programming skype: rodolfo.giometti Freelance ICT Italia - Consulente ICT Italia - www.consulenti-ict.it -- 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
