On 19-1-2017 13:36, Lior David wrote: > On 1/19/2017 2:24 PM, Valo, Kalle wrote: >> Maya Erez <qca_merez@xxxxxxxxxxxxxxxx> writes: >> >>> From: Lior David <qca_liord@xxxxxxxxxxxxxxxx> >>> >>> In fine timing measurements, the calculation is affected by >>> 2 parts: timing of packets over the air, which is platform >>> independent, and platform-specific delays, which are dependent >>> on things like antenna cable length and type. >>> Add a sysfs file which allows to get/set these platform specific >>> delays, separated into the TX and RX components. >>> There are 2 key scenarios where the file can be used: >>> 1. Calibration - start with some initial values (for example, >>> the default values at startup), make measurements at a known >>> distance, then iteratively change the values until the >>> measurement results match the known distance. >>> 2. Adjust the delays when platform starts up, based on known >>> values. >>> >>> Signed-off-by: Lior David <qca_liord@xxxxxxxxxxxxxxxx> >>> Signed-off-by: Maya Erez <qca_merez@xxxxxxxxxxxxxxxx> >> >> Can't this go via nl80211? sysfs is not really supposed to be used for >> something like this. >> > There is no nl80211 API for this (yet?). So come up with one...? > Will it be ok to put this in debugfs? Normally this will be in the board > file (as part of RF configuration) but it will be useful to play > with these values for debugging/diagnostics. What is doing the FTM measurements? Is it all done in user-space? That would mean you also need measurement data exported to user-space. How is that done? Intel has a FTM api proposal, but it has not been submitted upstream (yet?). Regards, Arend
