E/M noise is a pretty good source of entropy so we mix the FFT
measurements of the E/M spectrum to /dev/random pool. Note that
this doesn't increase the pool's entropy count but it still helps
on improving the output of /dev/(u)random.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Temp buffer is only used for fixing malformed frames, there is no
need to memset it every time.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
There is no reason to keep processing FFT reports if there is no
space left on the relayfs buffers for the results. This saves
lots of CPU cycles, especially on normal (non-short) reports.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
No need to copy the frame to the temporary buffer when its length
is ok.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Since we have lots of frames on a normal FFT report don't bother
processing the malformed ones. Only try to fix malformed frames
in case of a short FFT report (only a single frame on the report).
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Since we can identify the FFT frames on the report by checking the
consistency of their magnitude info, we can process all of them,
even when some of them are corrupted.
This patch introduces two functions to quickly verify the integrity
of the mag_info fields and some further tweaks to detect the frames
in the report and process them.
Note that in case of missing bytes we don't duplicate them, instead
we leave them as zeroes. This way we get less noise on the FFT plot.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
a) Check that the maximum magnitude is at the specified index
b) Check if the maximum magnitude index is at dc_pos and if so
calculate a new one (value at dc_pos is invalid)
c) Check if the specified maximum magnitude is indeed the maximum
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Since more checks and fixes will be added later and ath_cmn_process_fft is
already big enough.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Maximum magnitude index is a 5bit signed integer,
convert to an 8bit signed integer and then "shift" it so that it can be used
as an array index. Note that the current implementation adds +1 to the index
value (so it can't be used as an array index) and it's only valid for HT20
channels.
Note that the maximum magnitude index is not being used by
the userspace tools that parse FFT samples (they just use
maximum magnitude) so this doesn't break userspace compatibility.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
The relay_close() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
and rename exports from ath9k_spectral_* to ath9k_cmn_spectral_*
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
