First of all thanks for all the answers! I will try to comment for each of them below.
To introduce myself: I'm not a usual raspberry pi user and i'm not used to look or respond on the forum. I have read some topics and answered to some trivial of them recently, that's all. I'm an embedded electronic project manager working in the industry. I'm currently looking at the CM3+ for a new project (mainly because of the cost).
@DougieLawson and @PhilE: I don't know aBUGSworstnightmare, and I was not doubting of his expertise. I just want technical response, not just something I have to believe.
@jamesh: "However, it is possible to use the DSI interface in other ways if you have enough skill to build the hardware and write the software to use it. There is a user space driver for it in KMS." do you mean it's possible to use the interface for something else ? Or with a non official screen maybe ? Has indicated, i'm working in the industry, I'm not a hobbyist. Currently I'm building my system with Yocto, building the kernel is not an issue, developing some modules or patchs is also possible.
Maybe to ask the question differently I should give an example: I have recently worked with an iMX6 module (https://somlabs.com/product/visionsom-6ull/
), the documentation of the vendor provide the complete functionalities of the SOC (here: https://wiki.somlabs.com/index.php/Visi ... and_Pinout
) and the datasheet of the CPU is also available on the NXP website (https://www.nxp.com/products/processors ... e:i.MX6ULL
). If you look at this SOC, you can notice the LCD and CSI interfaces can be used for other purpose thanks to the pin muxing. That's very common and not an exception, I'm used to see this on this kind of product.
Today I simply wonder if pin muxing is available on the CM3+ pins which are considered DSI/CSI pins, using alternative functions of the GPIOs ? I should simply look at the full datasheet from Allwinner but it seems it is not available (or I have not found it!)
Another detailed question on the same subject: HDMI has an I2C port available on pins 173 and 175 of the CM3+. This port is called "I2C2" in the device tree. Is this port available for something else (connecting sensors) if I'm not using the HDMI ?