device-profile-hooks: add hook to select Voice Call profile

A "Voice Call" profile is supposed to be active during a call, even if
there is a higher priority device profile. Add a hook to select the
Voice Call profile when a call is active, and select a profile when
transitioning in and out of an active call.

src/config/wireplumber.conf

@@ -501,6 +501,11 @@ wireplumber.components = [
     name = device/select-profile.lua, type = script/lua
     provides = hooks.device.profile.select
   }
+  {
+    name = device/find-voice-call-profile.lua, type = script/lua
+    provides = hooks.device.profile.find-voice-call
+    requires = [ support.modem-manager, support.standard-event-source ]
+  }
   {
     name = device/find-preferred-profile.lua, type = script/lua
     provides = hooks.device.profile.find-preferred
@@ -526,7 +531,9 @@ wireplumber.components = [
     requires = [ hooks.device.profile.select,
                  hooks.device.profile.autoswitch-bluetooth,
                  hooks.device.profile.apply ]
-    wants = [ hooks.device.profile.find-best, hooks.device.profile.find-preferred,
+    wants = [ hooks.device.profile.find-voice-call,
+              hooks.device.profile.find-best,
+              hooks.device.profile.find-preferred,
               hooks.device.profile.state ]
   }
 

src/scripts/device/find-voice-call-profile.lua

@@ -0,0 +1,81 @@
+-- WirePlumber
+--
+-- Copyright © 2022 Collabora Ltd.
+-- Copyright © 2025 Richard Acayan
+--
+-- SPDX-License-Identifier: MIT
+--
+-- Find the best Voice Call profile for a device if there is an active call
+-- (adapted from device/find-best-profile.lua)
+
+cutils = require ("common-utils")
+log = Log.open_topic ("s-device")
+started = false
+
+alsa_devs_om = ObjectManager {
+  Interest {
+    type = "device",
+    Constraint { "device.api", "=", "alsa" },
+  }
+}
+
+mm = Plugin.find ("modem-manager")
+mm:connect ("voice-call-start", function ()
+  started = true
+  source = source or Plugin.find ("standard-event-source")
+
+  for device in alsa_devs_om:iterate () do
+    event = source:call ("push-event", "select-profile", device, nil)
+  end
+end)
+
+mm:connect ("voice-call-stop", function ()
+  started = false
+  source = source or Plugin.find ("standard-event-source")
+
+  for device in alsa_devs_om:iterate () do
+    event = source:call ("push-event", "select-profile", device, nil)
+  end
+end)
+
+SimpleEventHook {
+  name = "device/find-calling-profile",
+  before = "device/find-stored-profile",
+  interests = {
+    EventInterest {
+      Constraint { "event.type", "=", "select-profile" },
+    },
+  },
+  execute = function (event)
+    local selected_profile = event:get_data ("selected-profile")
+    if selected_profile then
+      return
+    end
+
+    if not started then
+      return
+    end
+
+    local device = event:get_subject ()
+    local dev_name = device.properties["device.name"] or ""
+
+    for p in device:iterate_params ("EnumProfile") do
+      local profile = cutils.parseParam (p, "EnumProfile")
+      local found = string.find (profile.name, "^Voice Call")
+      if profile.available == "yes" and found ~= nil then
+        if (not selected_profile) or selected_profile.priority < profile.priority then
+	  selected_profile = profile
+        end
+      end
+    end
+
+    if selected_profile then
+      log:info (device, string.format (
+          "Found best profile '%s' (%d) for device %s",
+          selected_profile.name, selected_profile.index, dev_name))
+      event:set_data ("selected-profile", selected_profile)
+    end
+  end
+}:register ()
+
+alsa_devs_om:activate ()