Here are the rules of contribution:

Your new module must have an example that builds against your UPM library.
Each commit must have a sign-off line by everyone who authored or reviewed them.
Commits must be named <file/module>: Some decent description.
You must license your module under a FOSS license. The recommended license is MIT but any permissive license is fine. Please consider that people using UPM may want to write proprietary programs with your sensors so we like to avoid GPL. If your license is not MIT please include a LICENSE file in src/mymodule/.
The top of each source file must contain a comment block containing the license information.
Please test your module builds before contributing and make sure it works on the latest version of libmraa. If you tested on a specific board/platform please tell us what this was in your PR.
Try not to break master. In any commit.
Attempt to have some decent API documentation as described in the the Writing sensor documentation guide.

Including the MIT license

Choosing the MIT license is preferred for the UPM repository. Below is the comment block needed at the top each source file:

    /*
     * The MIT License (MIT)
     *
     * Author: <your full name> 
     * Copyright (c) <year> <copyright holder>
     *
     * Author: <contributing author full name - if applicable> 
     * Copyright (c) <year> <copyright holder>
     *
     * Permission is hereby granted, free of charge, to any person obtaining a copy of
     * this software and associated documentation files (the "Software"), to deal in
     * the Software without restriction, including without limitation the rights to
     * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
     * the Software, and to permit persons to whom the Software is furnished to do so,
     * subject to the following conditions:
     *
     * The above copyright notice and this permission notice shall be included in all
     * copies or substantial portions of the Software.
     *
     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
     * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
     * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
     * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
     * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Code signing

The sign-off is a simple line at the end of the explanation for the patch, which certifies that you wrote it or otherwise have the right to pass it on as an open-source patch. The rules are pretty simple: if you can certify the below:

    Developer's Certificate of Origin 1.1

    By making a contribution to this project, I certify that:

    (a) The contribution was created in whole or in part by me and I
        have the right to submit it under the open source license
        indicated in the file; or

    (b) The contribution is based upon previous work that, to the best
        of my knowledge, is covered under an appropriate open source
        license and I have the right under that license to submit that
        work with modifications, whether created in whole or in part
        by me, under the same open source license (unless I am
        permitted to submit under a different license), as indicated
        in the file; or

    (c) The contribution was provided directly to me by some other
        person who certified (a), (b) or (c) and I have not modified
        it.

    (d) I understand and agree that this project and the contribution
        are public and that a record of the contribution (including all
        personal information I submit with it, including my sign-off) is
        maintained indefinitely and may be redistributed consistent with
        this project or the open source license(s) involved.

then you just add a line to each of your commits with --signoff saying

    Signed-off-by: Random J Developer <random@developer.example.org>

using your real name (sorry, no pseudonyms or anonymous contributions.) Unsigned commits will not be accepted.