ath10k is the mac80211 wireless driver for Qualcom Atheros QCA988x family of chips, which support IEEE 802.11ac. It was first included in Linux 3.11-rc1 released on 2013-07-14.
The ath10k driver is located under drivers/net/wireless/ath/ath10k directory. For more information see sources.
ath10k supports Qualcomm Atheros 802.11ac QCA98xx hw2.0 and QCA6174 based devices, here's a list of known products:
[1] The Compex WLE900VX card enumerates as PCI device on some PCs but not for some other PCs. The reason could possibly be PC hardware or kernel version. Detailed info: https://bugzilla.kernel.org/show_bug.cgi?id=84821. The Chaos Calmer wpj344a_150827_vCC.img provided by http://www.compex.com.sg/downloads/ can detect and enable the WLE900VX card with ath10k.
ath10k does NOT support older QCA98xx hw1.0 chips found, for example, from these devices:
Any SDIO or USB devices are not supported, but work is ongoing to add that.