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According to the documentation of ofono 1.17:

https://github.com/rilmodem/ofono/tree/master/doc

There are two interfaces for handsfree:

  • org.ofono.Handsfree
  • org.ofono.HandsfreeAudioManager

I need to access them in order to get pulseaudio working. It returns this error:

E: [pulseaudio] backend-ofono.c: Failed to register as a handsfree audio agent with ofono: org.freedesktop.DBus.Error.UnknownMethod: Method "Register" with signature "oay" on interface "org.ofono.HandsfreeAudioManager" doesn't exist

But that method exists (according to the docs above) and has that signature: object path, array{byte}.

Thus I guess it's not accessible rather than does not exist. I wrote a simple Python script to list the available services and org.ofono is there.

Then I added the code to list the objects:

def list_obj(bus, service, object_path):
    print(object_path)
    obj = bus.get_object(service, object_path)
    iface = dbus.Interface(obj, 'org.freedesktop.DBus.Introspectable')
    xml_string = iface.Introspect()
    for child in ElementTree.fromstring(xml_string):
        if child.tag == 'node':
            if object_path == '/':
                object_path = ''
            new_path = '/'.join((object_path, child.attrib['name']))
            list_obj(bus, service, new_path)

bus = dbus.SystemBus()
list_obj(bus, 'org.ofono.HandsfreeAudioManager', '/')

But I get the following errors:

dbus.exceptions.DBusException: org.freedesktop.DBus.Error.NameHasNoOwner: Could not get owner of name 'org.ofono.HandsfreeAudioManager': no such name

dbus.exceptions.DBusException: org.freedesktop.DBus.Error.ServiceUnknown: The name org.ofono.HandsfreeAudioManager was not provided by any .service files

I also checked the user policies for dbus, in /etc/dbus-1/system.d/ofono.conf:

<policy user="user">
  <allow own="org.ofono"/>
  <allow send_destination="org.ofono"/>
  <allow send_interface="org.ofono.SimToolkitAgent"/>
  <allow send_interface="org.ofono.PushNotificationAgent"/>
  <allow send_interface="org.ofono.SmartMessagingAgent"/>
  <allow send_interface="org.ofono.PositioningRequestAgent"/>
  <allow send_interface="org.ofono.HandsfreeAudioManager"/>
  <allow send_interface="org.ofono.Handsfree"/>   
</policy>

<policy at_console="true">
 <allow send_destination="org.ofono"/>   
</policy>

<policy context="default">
  <deny send_destination="org.ofono"/>   
</policy>

Of course I run ofono and the code above as user "user". I'm running out of ideas... what should I do further to fix the problem?

Mark
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  • Changing the list_obj call as follow: list_obj(bus, 'org.ofono', '/org/ofono/HandsfreeAudioManager') there are no errors, but it returns no methods. – Mark May 10 '16 at 07:45

1 Answers1

2

list_obj

https://github.com/rilmodem/ofono/blob/master/doc/handsfree-audio-api.txt describes the following interface:

Service     org.ofono
Interface   org.ofono.HandsfreeAudioManager
Object path /

and https://github.com/rilmodem/ofono/blob/master/doc/handsfree-api.txt describes this one:

Service     org.ofono
Interface   org.ofono.Handsfree
Object path [variable prefix]/{modem0,modem1,...}

This means that the service argument to the bus.get_object method has to be "org.ofono", and the object_path argument has to be / (for HandsfreeAudioManager) or [variable prefix]/{modem0,modem1,...} (for Handsfree).

Therefore, you should use obj(bus, 'org.ofono', '/').

Register

I'm guessing that it's possible that your org.ofono / object does not implement the org.ofono.HandsfreeAudioManager interface, or Register's signature is different than the one described in the docs.

You may want to try pydbus - https://github.com/LEW21/pydbus instead of the deprecated python-dbus bindings. It supports using Python's built-in help() function on the proxy objects, so that you'll be able to easily see all the supported interfaces, and the signatures of all their methods:

from pydbus import SystemBus
bus = SystemBus()
ofono = bus.get("org.ofono", "/")
help(ofono)

The returned ofono object exposes all the implemented interfaces at once, so it might be confusing if the object implements lots of interfaces. In that case, you can get a proxy object supporting only a single interface (like with python-dbus's dbus.Interface):

manager = ofono["org.ofono.HandsfreeAudioManager"]
help(manager)

However, unlike dbus.Interface (which fails silently), it'll throw a KeyError if the object does not implement this interface.

(Disclaimer: I'm the autor of pydbus)

LEW21
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  • Thanks for the detailed answer. I'll check if I can use pydbus on my system. – Mark May 11 '16 at 02:26
  • @LEW21 does pydbus allow TCP/IP SystemBus connection such as python-dbus': bus_obj=dbus.bus.BusConnection("tcp:host=localhost,port=12434")?? – sayo9394 Sep 07 '18 at 07:09