Add YUV420 sensor support

Robotics & Edge Computing Jetson Systems Jetson AGX Xavier
,
1

I’m trying to modify my YUV422(16bpp) sensor driver to capture YUV420(12bpp). The driver works fine with YUV422 I am able to capture stream with v4l2-ctl and gstreamer without any problems.

The sensor is able to stream YUV420 but I cannot capture it on jetson side. I have modified the device tree, and kernel images like so:

mode0 {
          mclk_khz = "48000";
          num_lanes = [34 00];
          tegra_sinterface = "serial_a";
          cil_settletime = "20";
          phy_mode = "DPHY";
          csi_pixel_bit_depth = "12";
          discontinuous_clk = "yes";
          mode_type = "yuv";
          pixel_phase = "uyvy";
          active_w = "640";
          active_h = "480";
          readout_orientation = [30 00];
          line_length = "640";
          pix_clk_hz = "280000000";
          embedded_metadata_height = [30 00];
};

Kernel files sensor_common.c and camera_common.c changes:

static int extract_pixel_format(
        const char *pixel_t, u32 *format)
{

          ...

          else if (strncmp(pixel_t, "yuv_uyvy12", size) == 0) //yuv420
                *format = V4L2_PIX_FMT_YUV420;
          ...
}

static const struct camera_common_colorfmt camera_common_color_fmts[] = {
        ...
        {
                MEDIA_BUS_FMT_UYVY8_1_5X8,
                V4L2_COLORSPACE_SRGB,
                V4L2_PIX_FMT_YUV420,
        },
        ...
}

Kernel compiles and installs successfully. After I insmod my driver I get a segmentation fault(NULL pointer derefference).

What is the correct way to support YUV420 format?

2

Hi,
YUV420 is not supported. It is hardware constraint. Please capture YUV422 such as UYVY or YUYV.