mac80211: use hardware flags for signal/noise units
trying to clean up the signal/noise code. the previous code in mac80211 had
confusing names for the related variables, did not have much definition of
what units of signal and noise were provided and used implicit mechanisms from
the wireless extensions.
this patch introduces hardware capability flags to let the hardware specify
clearly if it can provide signal and noise level values and which units it can
provide. this also anticipates possible new units like RCPI in the future.
for signal:
IEEE80211_HW_SIGNAL_UNSPEC - unspecified, unknown, hw specific
IEEE80211_HW_SIGNAL_DB - dB difference to unspecified reference point
IEEE80211_HW_SIGNAL_DBM - dBm, difference to 1mW
for noise we currently only have dBm:
IEEE80211_HW_NOISE_DBM - dBm, difference to 1mW
if IEEE80211_HW_SIGNAL_UNSPEC or IEEE80211_HW_SIGNAL_DB is used the driver has
to provide the maximum value (max_signal) it reports in order for applications
to make sense of the signal values.
i tried my best to find out for each driver what it can provide and update it
but i'm not sure (?) for some of them and used the more conservative guess in
doubt. this can be fixed easily after this patch has been merged by changing
the hardware flags of the driver.
DRIVER SIGNAL MAX NOISE QUAL
-----------------------------------------------------------------
adm8211 unspec(?) 100 n/a missing
at76_usb unspec(?) (?) unused missing
ath5k dBm dBm percent rssi
b43legacy dBm dBm percent jssi(?)
b43 dBm dBm percent jssi(?)
iwl-3945 dBm dBm percent snr+more
iwl-4965 dBm dBm percent snr+more
p54 unspec 127 n/a missing
rt2x00 dBm n/a percent rssi+tx/rx frame success
rt2400 dBm n/a
rt2500pci dBm n/a
rt2500usb dBm n/a
rt61pci dBm n/a
rt73usb dBm n/a
rtl8180 unspec(?) 65 n/a (?)
rtl8187 unspec(?) 65 (?) noise(?)
zd1211 dB(?) 100 n/a percent
drivers/net/wireless/ath5k/base.c: Changes-licensed-under: 3-Clause-BSD
Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index 4baa185..c1234ff 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -8029,17 +8029,10 @@
priv->ibss_beacon = NULL;
- /* Tell mac80211 and its clients (e.g. Wireless Extensions)
- * the range of signal quality values that we'll provide.
- * Negative values for level/noise indicate that we'll provide dBm.
- * For WE, at least, non-0 values here *enable* display of values
- * in app (iwconfig). */
- hw->max_rssi = -20; /* signal level, negative indicates dBm */
- hw->max_noise = -20; /* noise level, negative indicates dBm */
- hw->max_signal = 100; /* link quality indication (%) */
-
- /* Tell mac80211 our Tx characteristics */
- hw->flags = IEEE80211_HW_HOST_GEN_BEACON_TEMPLATE;
+ /* Tell mac80211 our characteristics */
+ hw->flags = IEEE80211_HW_HOST_GEN_BEACON_TEMPLATE |
+ IEEE80211_HW_SIGNAL_DBM |
+ IEEE80211_HW_NOISE_DBM;
/* 4 EDCA QOS priorities */
hw->queues = 4;