I did some research on the Internet, what I found are all about using the USB port on the laptop as a display out, to something like an external monitor, which aren't my concern.
Is it possible to use the USB 3.0 as display in for laptop? i.e. Take the video signal from somewhere, and display the video output on the display of the laptop, via the USB 3.0 port. An example will be like take the video output from a console and display the video on a laptop's monitor.
The required bandwidth, let's say for a 8 bit colour 1080p 60Hz signal, is equal to 1920*1080*8*3*60 bit/s = 356 MB/s < 625 MB/s (the theoretical max bandwidth of USB 3.0). So in in terms of bandwidth it's possible.
In terms of latency, I read from somewhere else that it is really small, so this shouldn't be a concern either.
Oh, and I know this isn't practical, or I better found a laptop with a HDMI-in port, or whatever. I just want to know if this is possible. Thanks in advance.
Best Answer
In other words, you want to turn your laptop into a display with USB interface. Theoretically, yes, it is possible. Under several conditions however. But practically, no.
Typically a USB display must conform to a special Video Class device (AV-class) capable of image rendering. The original proprietary interface was pioneered by DisplayLink. The USB device therefore must conform to certain endpoint structure, descriptor content, and a USB host must have a Virtual Graphics Card software/driver installed, which would create a virtual display, and transmit the image data over USB to the DisplayLink device.
So, the laptop port must be a Dual-Role-Port first, and be able to act as USB device. Many tablets and smartphones have a single DRP. When connected to USB host, they act as MTP (media transfer) or Mass Storage devices. They can act as webcam and stream video from laptop to host PC, but not in the opposite direction.
Therefore, the laptop must pretend to be a video streaming device. AFAIK, no DRP gadgets have implemented the Video rendering class. More, it is unclear if the standard implementations of OTG device controllers are capable of implementing of AV rendering class, although it is theoretically possible if SoC designers decided to configure the USB device controller IP to support AV class at silicon level. Which practically doesn't happen, unless somebody can correct me.