Pratyush, Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> wrote on Wed [2021-Mar-31 09:06:35 +0300]: > Hi, > > On 30/03/2021 20:33, Pratyush Yadav wrote: > > TI's J721E uses the Cadence CSI2RX and DPHY peripherals to facilitate > > capture over a CSI-2 bus. > > > > The Cadence CSI2RX IP acts as a bridge between the TI specific parts and > > the CSI-2 protocol parts. TI then has a wrapper on top of this bridge > > called the SHIM layer. It takes in data from stream 0, repacks it, and > > sends it to memory over PSI-L DMA. > > > > This driver acts as the "front end" to V4L2 client applications. It > > implements the required ioctls and buffer operations, passes the > > necessary calls on to the bridge, programs the SHIM layer, and performs > > DMA via the dmaengine API to finally return the data to a buffer > > supplied by the application. > > > > Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx> > > --- > > MAINTAINERS | 7 + > > drivers/media/platform/Kconfig | 11 + > > drivers/media/platform/ti-vpe/Makefile | 1 + > > drivers/media/platform/ti-vpe/ti-csi2rx.c | 964 ++++++++++++++++++++++ > > 4 files changed, 983 insertions(+) > > create mode 100644 drivers/media/platform/ti-vpe/ti-csi2rx.c > > Some quick comments: > > "ti-vpe" directory is not correct, this has nothing to do with VPE. That > said, the directory has already been abused by having CAL driver there, > perhaps we should rename the directory just to "ti". But if we do that, > I think we should have subdirs for cal, vpe and this new one. I agree with Tomi here. This should create a ti directory under media/platform and then add a directory under that specifically for this driver/IP as a first step. Not sure what the correct name for that directory should be but it should meaningful. As a follow on step then the other drivers can be relocated to a proper directory structure. > > "ti-csi2rx" is rather generic name. TI has had CSI-2 RX IPs before (CAL) > and probably will also have new ones in the future. If there's no clear > model name for the IP, as I think is the case here, it's probably best > to just use the SoC model in the name. E.g. the DSS on J7 is > "ti,j721e-dss". > > This driver implements the legacy video API. I think it would be better > (and easier to maintain) to only implement the media-controller API, > unless you specifically need to support the legacy API for existing > userspace. We just went through a major rework with CAL to make it media controller compatible in order to be able to handle CSI2 virtual channels. I think as this is a new driver/IP which perform the same type of service it makes sense to make use the more current API instead of the legacy one. > > Tomi Benoit
