On 02/19/2016 05:24 PM, Mauro Carvalho Chehab wrote: > Em Fri, 19 Feb 2016 14:24:08 +0100 > Hans Verkuil <hverkuil@xxxxxxxxx> escreveu: > >> Hi all, >> >> The soc-camera framework is a problem for reusability of sub-device drivers since >> those need access to the soc-camera framework. Which defeats the purpose of the >> sub-device framework. It is the reason why we still have a media/i2c/soc-camera >> directory for subdevs that can only work with soc-camera. >> >> Ideally I would like to drop soc-camera completely, but it is still in use. >> >> One of the largest users is Renesas with their r-car SoC, but Niklas Söderlund >> made a replacement driver that should make it possible to remove the soc-camera >> r-car driver, hopefully this year. >> >> What I would like to do is to move soc-camera drivers that we consider obsolete >> to staging, and remove them in 1-2 kernel cycles if nobody steps up. >> >> See also this past thread from Guennadi: >> >> http://www.spinics.net/lists/linux-media/msg89253.html >> >> And yes, I said in that thread that I was OK with keeping soc-camera as-is. But >> it still happens that companies pick this framework for new devices (the driver >> for the Tegra K1 for example). It is another reason besides the reusability issue >> for remove this framework more aggressively then I intended originally. >> >> >> We have the following drivers: >> >> - pxa_camera for the PXA27x Quick Capture Interface >> >> Apparently this architecture still gets attention (see the link to the thread >> above). But it does use vb1 which we really want to phase out soon. Does anyone >> know if this driver still works with the latest kernel? Because it is using vb1 >> it is a strong candidate for removing it (or replacing it with something better >> if someone steps up). >> >> - mx2_camera: i.MX27 Camera Sensor Interface >> >> Have not seen any development since April 2013 (mx2-camera: move interface >> activation and deactivation to clock callbacks by Guennadi). No idea if it still >> works or if it is still in use. Does anyone know? >> >> - mx3_camera: i.MX3x Camera Sensor Interface >> >> Have not seen any development since July 2013 (add support for asynchronous >> subdevice registration by Guennadi). Same as for mx2_camera: does it still work? >> Is it still in use? >> >> - omap1_camera: OMAP1 Camera Interface >> >> It uses vb1, so that's one very good reason for removing it. And as far as I >> know it is unused and likely won't work. >> >> - sh_mobile_ceu_camera: SuperH Mobile CEU Interface >> >> I worked on this, but I know it does function anymore. I'd say that this can >> be removed. >> >> - sh_mobile_csi2: SuperH Mobile MIPI CSI-2 Interface >> >> I don't have hardware to test, but I'd be surprised if it still works. Can >> someone test? If it is broken, then it can be moved to staging. >> >> - rcar_vin: R-Car Video Input (VIN) >> Will be replaced with a regular driver as mentioned above. >> >> - atmel-isi: ATMEL Image Sensor Interface (ISI) >> >> I believe this is still actively maintained. Would someone be willing to >> convert this? It doesn't look like a complex driver. >> >> Now I am not planning to remove soc-camera (yet), but at least we should get >> rid of unmaintained drivers, especially if they don't work anymore or if they >> use the old vb1 mess. >> >> And we can then take a good look at what remains. > > You're forgetting the I2C sensor cam drivers. There are 14 such drivers > under drivers/media/i2c/soc_camera/. I didn't forget those, but I thought that we should tackle those later. It's not so easy to remove the soc-camera dependency from them. I tried that once, and I think I could only make one or two of those drivers soc-camera independent :-( And without hardware you have no idea if they still work. The code is still available in git, even if we remove them. I don't really like the idea of keeping code in the kernel that very likely won't work after the soc-camera dependencies are removed. Regards, Hans > > I guess we should try to remove the soc_camera.h dependency from them, > making the still alive drivers to use the I2C sensor drivers directly. > > The point is that such sensors could be useful somewhere else. > For example, there are at least one or two such drivers that could be used > on em28xx-based cameras to replace some really ugly hacks there. Also, > gspca have sensor i2c code hardcoded on it. > > So, I would hate to lose those sensor drivers in the process. > > Regards, > Mauro > -- 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
