One point brought up regarding the inclusion of a camera is the fact that the T239 has removed hardware that T234 (Orin) uses to interface with cameras, specifically the NVCSI, VI & ISP blocks. However, reading up on the specifications of these blocks, it seems more likely they were removed due to being complete overkill for any possible camera application on the new Switch, rather than saying anything about the likelihood of the new Switch actually having a camera.
To explain, CSI is a standard interface for cameras, used in things like smartphones and cars. It's part of the MIPI set of standards, and supports two different physical interfaces, D-PHY, which allows long cable lengths but relatively low speeds, and C-PHY, which offers higher speeds but shorter cable lengths. Nvidia supports CSI 2.1 on Orin, and because it's designed for self-driving cars, it needs to handle a lot of data from a lot of cameras (and also needs to support many different types of camera). The NVCSI, VI and ISP blocks work together to get the image data from those cameras and make them available to software.
The NVCSI block specifically handles the actual interface with the cameras, and it takes the data in packets through either a D-PHY or C-PHY interface, decodes them, and sends the pixel data along to the two VI blocks. VI here stands for Video Input, and each of these takes the pixel data from the NVCSI block, converts the format into one which is useable by software, and puts it memory. The ISP, which stands for Image Signal Processor, isn't well documented, but it appears to work alongside the VI blocks performing things like format conversion.
All together, these blocks support a lot of functionality, and an enormous amount of bandwidth. The figures depend a lot on the formats used and so forth, but at a peak, the NVCSI, VI and ISP blocks can process over 160 Gb/s of camera data. As a point of comparison, the highest camera bandwidth I could reasonably see a new Switch requiring would be from a pair of 1080p/60Hz cameras at 12bpp. That comes to around 1.5 Gb/s of data. At the lower end of expectations, a single 720p/30Hz camera at 8bpp would come to around 0.2 Gb/s. The camera hardware on Orin isn't just overkill for a new Switch, it's absurd overkill. Even if Nintendo really go to town on AR, they'd struggle to use 1% of the capabilities of the hardware.
Now, I would have said that perhaps Nintendo could use a customised, scaled down version of the NVCSI, VI and ISP blocks, but I don't know how viable that would be given the difference in performance and functionality requirements. After all, Nintendo wouldn't need the flexibility of Orin's hardware, which needs to support almost every camera module available. Nintendo would only need to support the specific feature set of whatever camera module they use, which could lead to a much simpler interface. If Nintendo did require camera connectivity as part of T239, then my guess is that they would go with a completely separate, small fixed function interface, perhaps just licensing the IP for it, rather than having Nvidia design something in-house.
This doesn't necessarily mean that T239 does have camera interface hardware on it, but I'm not convinced that the lack of blocks like NVCSI is evidence that it doesn't, as they would never have been suitable for a device like the Switch in any case.
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