Per MAX9288 datasheet Table 2, YUV defaults to muxed input mode (Cb, Y0, Cr, Y1). Set register 0x60 INPUTBW = 1 to use normal input mode (CBY0, CrY1).
For muxed input mode, only uses the DIN0 ~ DIN7 pins of serializer for mux input (Cb, Y0, Cr, Y1).
For normal input, it uses DIN0 ~ DIN15. The DIN0 ~ DIN7 are Cb/Cr0 ~ Cb/Cr7 and DIN8 ~ DIN15 are Y0 ~ Y7.