The operation of the 4A system in Qualcomm chips is considered to be a trade secret, as such Qualcomm generally does not support raw Bayer cameras on the DragonBoard family. Only cameras with built-in ISP are supported (such as Omnivision OV5645). There are a very few Bayer cameras with binary only support in Android (none on Debian/OE), however most of these cameras modules are already obsolete (camera modules typically have a production lifespan of about 8 months).
Please contact your Arrow rep about this. Arrow has a couple of camera partners that have appropriate Qualcomm licenses and access to the documentation and tools, they can tune a specific camera module for your product, for a fee.
Full Disclosure: I am an employee of Qualcomm Canada, any opinions I may have expressed in this or any other post may not reflect the opinions of my employer.