Now I've had a chance to try this, I'm not sure I'm able to do what I want, if I'm reading the docs correctly. The docs seem to imply that RSSI filtering only works when UUIDs are set. In my case, the devices aren't advertising services. I did try setting RSSI by itself, but the result was that I got no PropertiesChanged signals at all. Am I missing something? As a general comment, I'd say that the hardcoded 8db delta is a bad idea. Firstly, 8 is an arbitrary choice. Also, it seems to me that it would be desirable to have two values settable through the filter for RSSI - 1) the delta and 2) the absolute threshold. That would make this feature a lot more flexible. It also seems desirable to be able to filter independent of UUIDs, but maybe I'm misinterpreting the docs. Neil On Fri, Jun 26, 2015 at 7:34 AM, Neil Martin <neil@xxxxxxx> wrote: > Hi Jakub, > > Thanks for the response. That makes sense - I'll give that a try. > > I'm running this on a Raspberry Pi with a Medialink USB adapter which > (I believe) has a Broadcom chipset. > > Neil > > On Thu, Jun 25, 2015 at 9:30 PM, Jakub Pawlowski <jpawlowski@xxxxxxxxxx> wrote: >> Hi Neil, >> >> On Thu, Jun 25, 2015 at 2:53 PM, Neil Martin <neil@xxxxxxx> wrote: >>> Hi, >>> >>> I've noticed that the bluetoothd console output shows a steady stream >>> of RSSI updates, yet only a fraction of these seem to translate into a >>> DBus PropertiesChanged signal. >>> >>> I've just seen 50 or so messages from bluetoothd of the form: >>> >>> bluetoothd[3867]: src/adapter.c:device_found_callback() hci0 addr >>> D0:4F:7E:2B:74:31, rssi -91 flags 0x0000 eir_len 15 >>> >>> while only seeing a single PropertiesChanged signal from dbus-monitor >>> with an RSSI update. >> >> That's because by default there is a threshold of 8db: >> >> #define RSSI_THRESHOLD 8 >> >> http://git.kernel.org/cgit/bluetooth/bluez.git/tree/src/device.c#n88 >> >> So if RSSI is changed less than 8dB you don't get any updates through D-Bus. >> >> If you want to get updates through D-Bus, you should call >> SetDiscoveryFilter first, see doc: >> "If one or more discovery filters have been set, the RSSI >> delta-threshold, that is imposed by StartDiscovery by default, will >> not be applied." >> http://git.kernel.org/cgit/bluetooth/bluez.git/tree/doc/adapter-api.txt#n48 >> >> >> Can I ask what kind of controller do you use ? Some just don't do >> packet deduplication during scan, and would report all packets >> received, that would explain flow of events from kernel. >> >> Jakub >> >>> >>> Neil >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
