A couple of developers have started to work on bringing support for Fm to the Ubuntu Touch phones, and progress is already under way, but it’s more complicated than it sounds. Many of the available SoC solutions used in today’s smartphones usually have FM support, but it’s not enabled by the makers of the phones. It’s not clear how or why FM support has fallen out of favor, but it’s no longer available by default.
Sturm Flut, the community developer that started the discussion around FM support, explained why it’s difficult to implement. “Thomas Voß and I spent quite some time finding out how the FM Radio functionality is implemented and talking about how it could be integrated. Because there is no standard, we have to pretty much handle it differently for every manufacturer.”
The good news: Our krillin/vegetahd (Aquaris E4.5/E5) kernels include the mt6627 driver for the FM Radio, the firmware files are shipped with our images (although in the wrong place), the radio is just a character device (“/dev/fm”), and a couple of ioctl() calls are enough to power it up and tune it to a frequency.
The bad news: In theory the FM Radio should just be connected to the audio chip as a normal input, and if you do a “pactl list sources” on the phone you will see an input port called “input-fm”. But if you switch to it while the FM Radio chip is powered on and tuned, you don’t hear anything, not even the “typical” FM noise.comments powered by Disqus