dug into some docs on the image sensor, and found the test patterns!

and two full resolution:

recall: ubuntu touch + updated ffmpeg.

settings for v4l2-ctl (test_pattern changed to 1 – 4)

v4l2-ctl -d /dev/video1 -l

User Controls

                       contrast (int)    : min=0 max=255 step=1 default=0 value=0 flags=slider
                     saturation (int)    : min=0 max=255 step=1 default=64 value=64 flags=slider
                            hue (int)    : min=0 max=359 step=1 default=0 value=0 flags=slider
        white_balance_automatic (bool)   : default=1 value=1 flags=update
                    red_balance (int)    : min=0 max=4095 step=1 default=0 value=0 flags=inactive, slider
                   blue_balance (int)    : min=0 max=4095 step=1 default=0 value=0 flags=inactive, slider
                       exposure (int)    : min=0 max=65535 step=1 default=0 value=16384
                 gain_automatic (bool)   : default=1 value=1 flags=update
                           gain (int)    : min=0 max=1023 step=1 default=0 value=16 flags=inactive, volatile
                horizontal_flip (bool)   : default=0 value=0
                  vertical_flip (bool)   : default=0 value=0
           power_line_frequency (menu)   : min=0 max=3 default=1 value=1

Camera Controls

                  auto_exposure (menu)   : min=0 max=1 default=0 value=1 flags=update

Image Processing Controls

                   test_pattern (menu)   : min=0 max=4 default=0 value=0

settings for the image capture

media-ctl -d /dev/media1 --set-v4l2 '"ov5640 2-003c":0[fmt:UYVY2X8/1280x720]'
ffmpeg -f rawvideo -pixel_format yuv420p -s 1280x720 -f video4linux2 -i /dev/video1 -vframes 1 ~/Pictures/$(date +"%Y%m%dT%H%M%S").jpg

and larger image (full sensor resolution, I think) with different pixel format

fname=$(date +"%Y%m%dT%H%M%S")
media-ctl -d /dev/media1 --set-v4l2 '"ov5640 2-003c":0[fmt:SBGGR8/2592x1944]'
ffmpeg -hide_banner -f rawvideo -pixel_format bayer_bggr8 -s 2592x1944 -f video4linux2 -i /dev/video1 -vframes 1 ~/Pictures/$fname-bggr8-big.jpg

have noticed full sensor pictures need more light.

solution:

March 9 Update

updated to ubports build 246 and found the highest resolution no longer works; and the id of the sensor changed.
you can see this with the command

media-ctl -d /dev/media1 -p -v

Opening media device /dev/media1
Enumerating entities
looking up device: 81:1
looking up device: 81:2
Found 2 entities
Enumerating pads and links
Media controller API version 5.5.0

Media device information
------------------------
driver          sun6i-csi
model           Allwinner Video Capture Device
serial
bus info
hw revision     0x0
driver version  5.5.0

Device topology
- entity 1: sun6i-csi (1 pad, 1 link)
            type Node subtype V4L flags 0
            device node name /dev/video1
	pad0: Sink
		<- "ov5640 3-004c":0 [ENABLED,IMMUTABLE]

- entity 5: ov5640 3-004c (1 pad, 1 link)
            type V4L2 subdev subtype Sensor flags 0
            device node name /dev/v4l-subdev0
	pad0: Source
		[fmt:UYVY2X8/1280x720]
		-> "sun6i-csi":0 [ENABLED,IMMUTABLE]

so a command to set resolution and image type is now:

media-ctl -d /dev/media1 --set-v4l2 '"ov5640 3-004c":0[fmt:UYVY2X8/1920x1080]'

The version changed also.  Searching online I see a change in the driver code that was made to allow only the highest resolution at 15 frames per second.

I am just using command line media-ctl, v4l2-ctl and ffmpeg commands; which I assume do not set the frame rate?

If anyone knows how to set frame rate via cli, comment!

found it, add @1/5 to end of setting;
oddly initially did not seem to work, needed to send command with time first with lower resolution, THEN the higher resolution one.

media-ctl -d /dev/media1 --set-v4l2 '"ov5640 3-004c":0[fmt:SBGGR8/1280x960@1/15]'
media-ctl -d /dev/media1 --set-v4l2 '"ov5640 3-004c":0[fmt:SBGGR8/2500x1600@1/15]'