Settings app doesn't implement DisplayPinCode Agent method

[Simon Fels]

When pairing with Bluetooth legacy devices (those using Bluetooth version < 2.1) we currently don't implement support for displaying a PIN code used for pairing. From the functionality point of view this doesn't cause any harm but if we do it would bring us more along with what the Bluetooth spec says. If we don't implement the DisplayPinCode Agent method BlueZ will use RequestPinCode instead which will require the user to enter the same PIN code on both devices rather than entering a displayed PIN code on just the responding device (initiating device will display the PIN code to enter).

See https://git.kernel.org/cgit/bluetooth/bluez.git/tree/doc/agent-api.txt?id=4.101#n64 for more details.

[Sebastien Bacher (seb128)]

Thanks

[Michael Terry (mterry)]

This sounds like what I am seeing when connecting to my bluetooth keyboard (1byone keyboard) -- I get redundantly asked on the phone to enter a code to then also enter on my keyboard. But my keyboard is bluetooth spec 3.0.

[Nephilim1973 (nephilim1973-e)]

Not working for MEDION BT Keyboard... (BT 3.0)

https://www.medion.com/de/service/_lightbox/handbuch.php?msn=50042613&prod=MEDION%20P81034%20%28MD%2086739%29%20A-DE%20S

Normally, keyboard sends a dialog to the paring device where you must enter a PIN (given from the keyboard).
On Ubuntu Touch, this dialog does not appear...

Loading module: 'libubuntu_application_api_touch_mirclient.so.3.0.0'
2015-09-06 18:06:01,733 - WARNING - file:///usr/share/ubuntu/settings/system/qml-plugins/bluetooth/PageComponent.qml:154:50: Unable to assign [undefined] to bool
UbuntuWindow - regular geometry
2015-09-06 18:06:02,110 - WARNING - file:///usr/share/ubuntu/settings/system/qml-plugins/bluetooth/PageComponent.qml:154:50: Unable to assign [undefined] to bool
2015-09-06 18:06:16,329 - WARNING - Could not create device: "Cannot allocate memory"
2015-09-06 18:06:26,869 - CRITICAL - Couldn't register agent at "/com/canonical/SettingsBluetoothAgent/90_7F_61_8E_B6_55"
2015-09-06 18:06:26,921 - WARNING - Could not create device: "Cannot allocate memory"
2015-09-06 18:06:35,892 - WARNING - Can't set device trusted before it is added in BlueZ
2015-09-06 18:06:36,640 - CRITICAL - Couldn't register agent at "/com/canonical/SettingsBluetoothAgent/90_7F_61_8E_B6_55"
2015-09-06 18:06:36,682 - WARNING - Could not create device: "Cannot allocate memory"
2015-09-06 18:06:45,273 - WARNING - QObject::startTimer: Timers cannot be started from another thread

[Simon Fels (morphis)]

@Nephilim1973: It looks like your device is running out of memory. Can you reproduce this after you've restarted the device and did not open any other app than the settings app? However what you see here is a different bug than what we describe here as the obvious memory allocation problem tells us. If this problem doesn't remain after a reboot we should move this to a new bug or wait until 1492892 gets fixed as that will improve the whole situation sustainable.

[Simon Fels (morphis)]

This will be implemented with the ongoing work of switch to BlueZ 5.

Code is part of https://code.launchpad.net/~morphis/ubuntu-system-settings/bluez5-support/+merge/271456 and will land together with all other BlueZ 5 bits.