Hi, On 05/11/2024 13:39, Jacopo Mondi wrote:
Could you clarify what other streams you plan to support ? As you support routing I presume you are preparing to capture multiple streams of data like image + embedded data, or to support sensors which sends data on different virtual channels ? How do you see this driver evolve ? Will it be augmented with an additional source pad directed to a video device where to capture embedded data from ? I'm wondering because if PAD_SINK become multiplexed, you won't be allowed to set a format there. It only works now because you have a single stream. Speaking of which, as you prepare to support multiple streams, I would specify the stream number when calling v4l2_subdev_state_get_format(). fmt = v4l2_subdev_state_get_format(state, format->pad, 0);Thanks for your suggestion. But this MIPI CSI2 hardware module doesn't have the ability to separate data , such as image + embedded data. So there are no plans to support other streams.I see. Now that I've reviewed the adapter subdevice path I realized that it's the adapter that can split data based on VC/DT to either the ISP direct path or to DDR. The CSI-2 RX then transports streams as received from the sensor directly to the adapter. In order to support capturing embedded data to DDR in the adapter the embedded data stream needs a representation in this subdevice as well, so that the source pad is multiplexed as well and the adapter receives two streams that it can eventually split. Sensor CSI-2Rx Adapter +-----------+ +------+ +--------+ 0-- ED --\ | | | | /->0---> Embedded Data (DDR) | ->0====>0 ==== 0 ====> 0====| | 0-- I ---/ | | | | \->0---> Image (ISP) +-----------+ +------+ +--------+ When going to support embedded data capture this driver should create two routes and allow enabling/disabling the embedded data one.
This depends on the hardware. What's the bus between the CSI-2 rx and the adapter? If it's a custom bus that basically allows passing forward anything received from the CSI-2 bus, then the user should be free to configure any routes in the CSI-2 RX subdevice.
The adapter subdev, however, as it is limited by the HW, should only support two streams if that is what the hardware supports.
Tomi in cc for inputs. For now, if you don't support capturing embedded data, I would remove routing support from here and from the adapter.
Right, if the drivers only support a single stream, just drop the routing support.
Tomi
