The Kamlan 28mm f/1.4 (announcement) will be available for Canon EOS M systems, and for Sony E, Fuji X, and M4/3 mounts. You can order it for $199 on this Kickstarter page. Delivery is expected for August 2018.
DPReview posted a set of sample images shot with the Kamlan 28mm f/1.4, unfortunately not on a Canon EOS M but on Fuji and Sony gear. The Kamlan 28mm f/1.4 lens appears to be a pretty good performer for the money it costs.