hello matanh,
tegra-camera-platform{} it’s device tree settings, which is came from the device tree binary, i.e. tegra194-p3668-all-p3509-0000.dtb.
there’s an option to load device tree binary from file system. you may review /boot/extlinux/extlinux.conf , it’s FDT entry to load the device tree binary from file system. you may revise the extlinux.conf by adding a new boot options for loading your customize dtb, or updating the default FDT entry to point-to your customize dtb.
moreover,
please searching around, there’re some similar topics for using tca9548,
for example,
Not detecting GMSL 2 camera using i2cdetect.
Jetson TX2 TCA9548 I2C switch and TCA6408 I2C GPIO Expander.
I2C for 4 MIPI CSI cameras with custom carrier board.