Sharing I2C signals with MIPI camera

I am connecting a MIPI camera to the Jetson Nano board which uses the CAM_I2C_SCL and CAM_I2C_SDA signals. I would like to connect other I2C devices as well.
Can the devices share CAM_I2C_SCL and CAM_I2C_SDA with the MIPI camera? Or should they be used exclusively for the MIPI camera?


hello elieva,

may I have more details about your use-case.
there’s CSI mux to share the i2c address. you may check below reference driver for an example,

        cam_i2cmux {
                i2c-parent = <&i2c7>;
                i2c@0 {
                        rbpcv2_imx219_a@10 {
                i2c@1 {
                        rbpcv2_imx219_e@10 {

Nano supports the camera stream combinations with
(1) three quad-lane camera streams, or
(2) two quad-lane plus two dual-lane camera streams, or
(3) one quad-lane plus three dual-lane.

you should also access the Nano Product Design Guide.
please refer to [Chapter 8. MIPI CSI Video Input] for pin description and also CSI connection options for more details.

In my design I have one MIPI camera, one IMU and one Flir Lepton 3.5. The MIPI camera uses the CAM_I2C_SDA and CAM_I2C_SCL. The IMU and the Flir require as well an I2C connection. I would like to minimise the number of I2C used.

If I understand correctly it is possible to use CAM_I2C between several MIPI cameras, but in my case I have only one MIPI camera and want to share the CAM_I2C signals between the MIPI camera, the IMU and the Flir.

I am a bit confused because in the Nano Product Design Guide, Chapter 10.Miscellaneous Interfaces p.56, it is said about the CAM_I2C_SDA/SCL: “Used as camera module control interface or available for misc. 3.3V I2C devices.”.
So I am not sure if I can use CAM_I2C signals for a camera module control interface and for misc. I2C devices at the same time.

hello elieva,

that CSI mux to share the i2c address were based-on multiple MIPI camera use-case.
may I have more details about why sharing CAM_I2C signals between MIPI camera, IMU and FLIR. what’s your use-case.

Hello Jerry,
I am designing a board with the Jetson Nano SOM and another board that contains the peripherals. Due to size limitation, I am simply trying to use the minimum numbers of pins between the two boards. It is why I would prefer to have only one I2C shared between all the peripherals. If it is not possible to use only CAM_I2C, I would use another I2C for the IMU and the Flir. I was just trying to avoid the additional pins required for the second I2C ;)

hello elieva,

we did not tried to enable CAM_I2C signals for camera module control and for misc devices.
please use another i2c for communication.

Hello Jerry,
Thanks for your help!