VC MIPI OV9281, Как настроить

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1/17/2020 How to setup a VC MIPI OV9281 on a Raspberry PI Model 3B+
https://www.vision-components.com/fileadmin/external/documentation/hardware/VC_MIPI_OV9281_Raspberry_PI_Model_3BPlus/index.html 10/13
4 Troubleshooting and Background Information
4.1 Q/A
Problem:
Running make fails with an error:
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make[1]: *** /lib/modules/4.14.79-v7+/build: No such file or directory. Stop.
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Solution:
The system needs the build tools of the kernel to build the sensor driver (which itself is a kernel module). They can be obtained by installing the RaspberryPi
Kernel Headers package named raspberrypi-kernel-headers, see
https://www.raspberrypi.org/documentation/linux/kernel/headers.md
Problem:
The sensor module driver cannot be started, it shows an error:
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[ 4.773298] ov9281 0-0060: Error -5 setting default controls
[ 4.773346] ov9281: probe of 0-0060 failed with error -5
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Solution:
Be sure no other device is connected to the I²C bus 0! For example, the touch screen controller of the Raspberry PI display may not be connected.
Check the orientation of the cable at the sensor side as well as at the cpu side. Also check if the cable and the sockets are orthogonal.
4.2 Driver Knowledge
The following tasks have to be done to do an image acquisition with the camera sensor:
Information about the new sensor hardware and its connector must be provided to the kernel by adding it to the so-called kernel device tree as overlay.
This device tree overlay must be applied to the kernel device tree.
For the driver to communicate with the sensor the I²C bus must be set up to connect between the CPU and the MIPI socket.
The driver itself must be installed as kernel modules.
Contiguous memory must be reserved for the captured image.
Note
On this Raspberry PI model the pins used for trigger input and output are hard-wired to some GPIO, so external triggering is not possible.
4.2.1 Providing the device tree overlay
Trigger input is hardwired to pin 133, trigger output to pin 134, so not
useable.