Allwinner Technology is the Chinese company producing a range of low-end SoCs for Android tablets and other devices. Allwinner hardware is popular with many in the open-source community due to their SoCs appearing in lower-cost hardware and the thriving Linux-SunXi community. Unfortunately, Allwinner as a company is still "learning" to be open-source friendly and to not violate the GPL and other licenses.
Allwinner has violated the GPL multiple times, obfuscated their code, screwed around with their licenses, etc. They have said they're taking actions internally to improve the situation and last month at least released some open-source CedarX code finally, but it's still a long-road ahead.
It will be interesting to see if Allwinner joining the Linux Foundation has any positive, long-term benefits for the open-source community. While one would think that they'd now clean up their game and stop violating the GPL, etc, they've also been members of Linaro since last year and that didn't seem to avoid their issues in the past few months.
Other new Linux Foundation Members are Datto, LINBIT, and Nutanix. More details via the Linux Foundation press release.