Help with OV5640 camera and Bayer format

Help with OV5640 camera and Bayer format

[Laura Nao]

Hi all,

I'm trying to enable RAW format on a ov5640 camera. I'm using a custom 
imx8mm based board, with a 4.14 kernel based on the 
rel_imx_4.14.98_2.0.0_ga branch from nxp. I tried capturing some RAW 
frames using v4l-utils using the following commands:

- RAW8: v4l2-ctl -d /dev/video0 --verbose 
--set-fmt--video=width=2592,height=1944,pixelformat=BA81 --stream-mmap 
--stream-count=1 --stream-to=raw8_2592x1944.raw

- RAW10: v4l2-ctl -d /dev/video0 --verbose 
--set-fmt-video=width=2592,height=1944,pixelformat=BG10 --stream-mmap 
--stream-count=1 --stream-to=raw10_2592x1944.raw

When a RAW frame is captured, a bunch of CRC errors shows up in the 
kernel log, like the ones below:

     6,15197,289730726,-;mxc_mipi-csi.0: CRC Error: 1
     6,15198,289730734,-;mxc_mipi-csi.0: Frame Start: 1
     6,15199,289730738,-;mxc_mipi-csi.0: status: 01000002
     6,15200,289730773,-;mxc_mipi-csi.0: CRC Error: 2
     6,15201,289730778,-;mxc_mipi-csi.0: status: 00000002
     6,15202,289730795,-;mxc_mipi-csi.0: CRC Error: 3
     6,15203,289730799,-;mxc_mipi-csi.0: status: 00000002
     6,15204,289730809,-;mxc_mipi-csi.0: CRC Error: 4

Resulting images are completely garbled. This happens for both 8-bit and 
10-bit formats. Currently I'm trying to get this working with 8-bit 
mode, before moving on to 10-bit. Capture in YUV format works fine.

For reference, I'm using ov5640_mipi_v2 driver for the camera, which I 
modified to add register configuration for RAW mode and support for the 
MEDIA_BUS_FMT_SBGGR8_1X8 format. The ov5640 registers I set for enabling 
RAW mode are:

0x3034 = 0x18  // 8-bit mode
0x4300 = 0x00  // Output data format: RAW BGGR
0x501F = 0x03  // ISP Format: ISP RAW (DPC)

Drivers used on the board for the MIPI CSI layer are mx6s_capture.c and 
mxc_mipi_csi.c .

Does anyone have any insight on what might be causing these errors?

Any help would be appreciated!

Best,

Laura