Hi Tomi
Thanks very much for your reply.
On 2024/11/5 20:08, Tomi Valkeinen wrote:
[ EXTERNAL EMAIL ]
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 bus between CSI-2 rx and the adapter is not a custom bus and can't
be configured by user.
The adapter subdev, however, as it is limited by the HW, should only
support two streams if that is what the hardware supports.
Yes, the adapter HW only supports embedded data and image.
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
Will drop the routing support due to the hardware limit.
