Hi Andrzej, On Wed, May 28, 2014 at 10:24 PM, Andrzej Kaczmarek <andrzej.kaczmarek@xxxxxxxxx> wrote: > Hi Luiz, > > On 27 May 2014 14:49, Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> wrote: >> Hi, >> >> On Tue, May 27, 2014 at 10:52 AM, Andrzej Kaczmarek >> <andrzej.kaczmarek@xxxxxxxxx> wrote: >>> From: Lukasz Rymanowski <lukasz.rymanowski@xxxxxxxxx> >>> >>> This patch introduces API to monitor connection parameters. >>> >>> New device properties are introduced: ConnectionRSSI, ConnectionTXPower >>> and ConnectionTXPowerMax. >>> >>> Client can request to poll for updates of RSSI and TX power via Start- >>> and StopConnectionMonitor methods. >>> --- >>> doc/device-api.txt | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ >>> 1 file changed, 56 insertions(+) >>> >>> diff --git a/doc/device-api.txt b/doc/device-api.txt >>> index 577ee60..67f573c 100644 >>> --- a/doc/device-api.txt >>> +++ b/doc/device-api.txt >>> @@ -100,6 +100,35 @@ Methods void Connect() >>> Possible errors: org.bluez.Error.DoesNotExist >>> org.bluez.Error.Failed >>> >>> + >>> + void StartConnectionMonitor() >>> + >>> + This method starts connection monitor session. This >>> + includes link RSSI and TX power. >>> + Use StopConnectionMonitor to release the sessions >>> + acquired. >>> + >>> + This process will start updating connection-related >>> + properties, e.g. ConnectionRSSI and ConnectionTXPower. >>> + >>> + Note that all sessions for device are released when >>> + device is disconnected and it's required to start >>> + sessiong again once reconnected. >>> + >>> + Possible errors: org.bluez.Error.Busy >>> + org.bluez.Error.NotConnected >>> + >>> + void StopConnectionMonitor() >>> + >>> + This method stops previous StartConnectionMonitor >>> + session. >>> + >>> + Note that connection monitor is shared between all >>> + monitor sessions thus calling StopConnectionMonitor >>> + releases a single session. >>> + >>> + Possible errors: org.bluez.Error.Failed >>> + >>> Properties string Address [readonly] >>> >>> The Bluetooth device address of the remote device. >>> @@ -193,3 +222,30 @@ Properties string Address [readonly] >>> >>> Received Signal Strength Indicator of the remote >>> device (inquiry or advertising). >>> + >>> + int16 ConnectionRSSI [readonly, optional] >>> + >>> + Received Signal Strength Indicator of connected remote >>> + device. >>> + >>> + This property is present only if device is connected >>> + and will be updated if at least one monitoring session >>> + is active. >>> + >>> + Note that RSSI has different units for BR/EDR (dB) >>> + and LE (dBm) as specified in BT Core ver. 4.1, Vol. 2, >>> + Part E, Chapter 7.5.4 >>> + >>> + int16 ConnectionTXPower [readonly, optional] >>> + >>> + Transmit power level to connected remote device. >>> + >>> + This property is present only if device is connected >>> + and will be updated if at least one monitoring session >>> + is active. >>> + >>> + int16 ConnectionTXPowerMax [readonly, optional] >>> + >>> + Maximum transmit power level to connected remote device. >>> + >>> + This property is present only if device is connected. >>> -- >>> 1.9.3 >> >> IMO this API is too low level, if there is a reliable way to calculate >> the link quality we should do it and probably expose as a single >> property in percentage like we see in WiFi and other technologies, >> trying to push this to the application to figure out is probably bad >> idea since different applications may come up with different results. >> >> I would follow connman API design: >> >> uint8 Strength [readonly] >> >> Indicates the signal strength of the service. This >> is a normalized value between 0 and 100... > > There's nothing to calculate here since RSSI and TX power are measured > in different "directions". Actually you can calculate pathloss once > you have RSSI from *local* side and TX power from *remote*. This is > what PXP does using TPS, (but it only works over LE). By having these > values exposed to application you can make proper PXP application and > even do this on BR/EDR. But why you want to do PXP as an application and not as a plugin? Both PXP and TPS should be very simple to be implemented as plugin since we have this info over MGMT interface. -- Luiz Augusto von Dentz -- 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
