Does Rock960 has support for camera output GREY (Y8)

Board based on the Rockchip RK3399 - ARM Cortex-A72 Dual-core up to 1.8GHz + Cortex A53 Quad-core up to 1.4GHz
Hi,
i am trying to add GREY sensor support with rock960. i read ISP cannot be bypassed , incoming stream should pass through ISP. but when i went through GREY format related support in ISP driver , i am not finding any . how to add support for MEDIA_BUS_FMT_Y8_1X8 (GREY).

There are lots of parameters like below,

              .mbus_code      = MEDIA_BUS_FMT_Y8_1X8,
              .fmt_type       = FMT_YUV,
              .mipi_dt        = CIF_CSI2_DT_RAW8,
              .yuv_seq        =  ??,
              .bus_width      = 8,

Please guide me how we can add GREY support in ISP driver . Both ISP input and output side. (dont want any ISP processing as of now)

Thanks