On 26/04/2020 02:19, Dmitry Osipenko wrote: > 26.04.2020 02:44, Sowjanya Komatineni пишет: > ... >>> How much of the T210 code could be reused by T186/194? >> >> vi/csi are common driver where soc structure should be populated for >> T186/T194 >> >> Tegra210.c can't be reused for Tegra186/t194 as programming seq is a >> whole lot diff >> > > How are you going to separate Tegra210/186/194 drivers from each other? > I don't think you'll want to have one "fat" driver that covers all those > SoCs, won't you? As long as the differences between SoCs are small, the media subsystem policy is to keep it all in one driver. You might split off some of it into separate SoC-specific sources that are included only if selected in the Kconfig (see e.g. drivers/staging/media/hantro/ or drivers/staging/media/imx/). If that makes sense for the Tegra, then that's a perfectly fine option. But creating multiple drivers for SoCs that only differ in relatively minor ways is not recommended. Also, these drivers allocate *huge* amounts of memory when streaming video, so a somewhat bigger driver is not something you'll notice. Keeping things readable, simple and maintainable is much more important. Regards, Hans > > In the end it should be three modules: tegra210-video.ko > tegra186-video.ko tegra194-video.ko. > > Using a per-SoC OPS doesn't allow you to do that because the "root" > driver will have to lookup OPS' code symbols of every SoC, and thus, the > unwanted driver modules will get auto-loaded if you'll try to factor out > the OPS into a separate driver modules. >
