Hi Daniel, On 25.08.2017 17:10, Daniel Mack wrote: > Hi Todor, > > Thanks a lot for working on the upstream support for this! > > On 08/08/2017 03:30 PM, Todor Tomov wrote: >> +The Camera Subsystem hardware found on 8x16 processors and supported by the >> +driver consists of: >> + >> +- 2 CSIPHY modules. They handle the Physical layer of the CSI2 receivers. >> + A separate camera sensor can be connected to each of the CSIPHY module; >> +- 2 CSID (CSI Decoder) modules. They handle the Protocol and Application layer >> + of the CSI2 receivers. A CSID can decode data stream from any of the CSIPHY. >> + Each CSID also contains a TG (Test Generator) block which can generate >> + artificial input data for test purposes; >> +- ISPIF (ISP Interface) module. Handles the routing of the data streams from >> + the CSIDs to the inputs of the VFE; >> +- VFE (Video Front End) module. Contains a pipeline of image processing hardware >> + blocks. The VFE has different input interfaces. The PIX input interface feeds >> + the input data to the image processing pipeline. Three RDI input interfaces >> + bypass the image processing pipeline. The VFE also contains the AXI bus >> + interface which writes the output data to memory. > > [I'm based on the 4.9 Linaro downstream version of this code right now, > but at a glance the driver version there looks very much identical to > this one.] > > Could you explain how ISPIF, CSID and CSIPHY are related? > > I have a userspace test setup that works fine for USB webcams, but when > operating on any of the video devices exposed by this driver, the > lowlevel functions such as .s_power of the ISPIF, CSID, CSIPHY and the > sensor driver layers aren't called into. Have you activated the media controller links? The s_power is called when the subdev is part of a pipeline in which the video device node is opened. You can see example configurations for the Qualcomm CAMSS driver on: https://github.com/96boards/documentation/blob/master/ConsumerEdition/DragonBoard-410c/Guides/CameraModule.md This will probably answer most of your questions. > > The general setup seems to work fine though. The sensor is probed, > camss_subdev_notifier_complete() is called, and the v4l2 subdevices > exist. But the stream start is not propagated to the other layers, and > I'm trying to understand why. > > My DTS looks something like this right now, and the hardware is an > APQ8016 board (Variscite DART SD410). > > &i2c { > cam0: ov5640@3c { > compatible = "ovti,ov5640"; > reg = <0x3c>; > > // clocks, regulators, gpios etc are omitted > > port { > cam0_ep: endpoint { > clock-lanes = <1>; > data-lanes = <0 2>; > remote-endpoint = <&csiphy0_ep>; > }; > }; > }; > }; > > &camss { > ports { > port@0 { > reg = <0>; > csiphy0_ep: endpoint { > clock-lanes = <1>; > data-lanes = <0 1 2 3>; As far as I know the OV5640 has a two data lane CSI2 interface so this will probably look like: data-lanes = <0 2>; > qcom,settle-cnt = <0xe>; > remote-endpoint = <&cam0_ep>; > }; > }; > }; > }; > > Also, which video device should be opened when accessing the cameras on > each of the hardware ports? And what are the other two devices doing? > > I'm sure I'm missing something trivial, but at least I can't find this > information in the documentation. > > > Thanks, > Daniel > -- Best regards, Todor Tomov
