On 10/23/2017 10:54 PM, Johannes Berg wrote:
On Mon, 2017-10-23 at 13:59 -0700, Ben Greear wrote:
The CSI data has variable length [1] but it's fundamentally always tied
to a specific frame and as such we've always attached it to that frame
using a radiotap vendor namespace.
You can easily implement that in a mac80211 driver since it has support
for that via RX_FLAG_RADIOTAP_VENDOR_DATA and the associated struct
ieee80211_vendor_radiotap that you put into the skb's head.
Why should anything else be needed?
So this would only show up in user-space in something like a pkt-capture?
Sure. But since you can easily add virtual monitor interfaces at any
time, that doesn't really mean anything.
Adding a monitor device is a pretty big hammer on ath10k, at least, and
probably not something one would want running continuously in a production
environment.
The CSI data is one part, but tx-beamforming is another area of interest.
If I get a chance, I'll try to add a way to pass some of this opaque
info up through netlink events. I'm thinking something like:
mac80211_nl_send_opaque_event(mac80211-handle, int data-type, u8* data, int data_len);
data-type would be:
NLD_ATH_CSI_DATA = 0,
NLD_ATH_TXBF_DATA = 1,
NLD_PRIVATE_START = 5000,
....
'iw events' could be made to dump raw hex for external programs to decode, or maybe
decode it a bit itself in some cases. And, third-party programs can open a netlink
monitor socket and get the data directly.
Thanks,
Ben
--
Ben Greear <greearb@xxxxxxxxxxxxxxx>
Candela Technologies Inc http://www.candelatech.com
