wireless: remove remaining qual code
This removes the remaining users of the rx status 'qual' field and the field itself. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:

committed by
John W. Linville

parent
5e31258945
commit
671adc93b6
@@ -1299,47 +1299,6 @@ int iwl3945_calc_db_from_ratio(int sig_ratio)
|
||||
return (int)ratio2dB[sig_ratio];
|
||||
}
|
||||
|
||||
#define PERFECT_RSSI (-20) /* dBm */
|
||||
#define WORST_RSSI (-95) /* dBm */
|
||||
#define RSSI_RANGE (PERFECT_RSSI - WORST_RSSI)
|
||||
|
||||
/* Calculate an indication of rx signal quality (a percentage, not dBm!).
|
||||
* See http://www.ces.clemson.edu/linux/signal_quality.shtml for info
|
||||
* about formulas used below. */
|
||||
int iwl3945_calc_sig_qual(int rssi_dbm, int noise_dbm)
|
||||
{
|
||||
int sig_qual;
|
||||
int degradation = PERFECT_RSSI - rssi_dbm;
|
||||
|
||||
/* If we get a noise measurement, use signal-to-noise ratio (SNR)
|
||||
* as indicator; formula is (signal dbm - noise dbm).
|
||||
* SNR at or above 40 is a great signal (100%).
|
||||
* Below that, scale to fit SNR of 0 - 40 dB within 0 - 100% indicator.
|
||||
* Weakest usable signal is usually 10 - 15 dB SNR. */
|
||||
if (noise_dbm) {
|
||||
if (rssi_dbm - noise_dbm >= 40)
|
||||
return 100;
|
||||
else if (rssi_dbm < noise_dbm)
|
||||
return 0;
|
||||
sig_qual = ((rssi_dbm - noise_dbm) * 5) / 2;
|
||||
|
||||
/* Else use just the signal level.
|
||||
* This formula is a least squares fit of data points collected and
|
||||
* compared with a reference system that had a percentage (%) display
|
||||
* for signal quality. */
|
||||
} else
|
||||
sig_qual = (100 * (RSSI_RANGE * RSSI_RANGE) - degradation *
|
||||
(15 * RSSI_RANGE + 62 * degradation)) /
|
||||
(RSSI_RANGE * RSSI_RANGE);
|
||||
|
||||
if (sig_qual > 100)
|
||||
sig_qual = 100;
|
||||
else if (sig_qual < 1)
|
||||
sig_qual = 0;
|
||||
|
||||
return sig_qual;
|
||||
}
|
||||
|
||||
/**
|
||||
* iwl3945_rx_handle - Main entry function for receiving responses from uCode
|
||||
*
|
||||
|
Reference in New Issue
Block a user