A select few drivers send this instead of SIGNAL_MBM. The docs say this value is the signal 'in unspecified units, scaled to 0..100'. The range for SIGNAL_MBM is -10000..0 so this can be scaled to the MBM range easy enough... Now, this isn't exactly correct because this value ultimately gets returned from GetOrderedNetworks() and is documented as 100 * dBm where in reality its just a unit-less signal strength value. Its not ideal, but this patch at least will fix BSS ranking for these few drivers. --- src/scan.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) I am fine leaving this on the list until we get an answer from the original thread about what driver this happened with: https://lists.01.org/hyperkitty/list/iwd@lists.01.org/thread/PLYNHZWEENY3... If its not one of these drivers, and not related to SIGNAL_UNSPEC, we will need to investigate further. diff --git a/src/scan.c b/src/scan.c index de507ba3..99813952 100644 --- a/src/scan.c +++ b/src/scan.c @@ -1372,6 +1372,22 @@ static bool scan_parse_bss_information_elements(struct scan_bss *bss, return have_ssid; } +/* + * Maps 0..100 values to -10000..0 + * + * This isn't really mapping to mBm since the input is unit-less and we have no + * idea what the driver itself does to come up with this 'strength' value but + * this is really the best that can be done for these drivers (its only 4 in + * tree drivers after all). + */ +static int32_t signal_unspec_to_mbm(uint8_t strength) +{ + if (L_WARN_ON(strength > 100)) + return 0; + + return ((int32_t)strength * 100) - 10000; +} + static struct scan_bss *scan_parse_attr_bss(struct l_genl_attr *attr, struct wiphy *wiphy, uint32_t *out_seen_ms_ago) @@ -1414,6 +1430,13 @@ static struct scan_bss *scan_parse_attr_bss(struct l_genl_attr *attr, bss->signal_strength = *((int32_t *) data); break; + case NL80211_BSS_SIGNAL_UNSPEC: + if (len != 1) + goto fail; + + bss->signal_strength = + signal_unspec_to_mbm(l_get_u8(data)); + break; case NL80211_BSS_INFORMATION_ELEMENTS: ies = data; ies_len = len; -- 2.31.1