switch-on-port-available: Fix switching away from unplugged headphones

Commits 323195e305 ("switch-on-port-available: Switch to headphones on
unknown availability") and d83ad6990e ("module-alsa-card: Drop
availability groups with only one port") broke switching from headphones
to speakers when headphones are unplugged. switch_from_port() selects
speakers, whose availability is unknown and availability group is unset,
and then calls switch_to_port(). The new logic in switch_on_port()
unintentionally blocked that switch.

This patch moves the problematic logic from switch_to_port() to
port_available_hook_callback() where it doesn't interfere with
switch_from_port().

Fixes: https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/1043

1 files changed, 28 insertions, 26 deletions

diff --git a/src/modules/module-switch-on-port-available.c b/src/modules/module-switch-on-port-available.c
index a7259cfad..84b856659 100644
--- a/src/modules/module-switch-on-port-available.c
+++ b/src/modules/module-switch-on-port-available.c
@@ -234,32 +234,6 @@ static void switch_to_port(pa_device_port *port) {
     if (pp.is_port_active)
         return; /* Already selected */
 
-    /* If a port availability became unknown, let's see if it's part of some
-     * availability group. If it is, it is likely to be a headphone jack that
-     * does not have impedance sensing to detect whether what was plugged in
-     * was a headphone, headset or microphone. In desktop environments that
-     * support it, this will trigger a user choice to select what kind of
-     * device was plugged in. However, let's switch to the headphone port at
-     * least, so that we have don't break functionality for setups that can't
-     * trigger this kind of interaction.
-     *
-     * We should make this configurable so that users can optionally override
-     * the default to a headset or mic.
-     */
-    if (port->available == PA_AVAILABLE_UNKNOWN) {
-        /* Not part of a group of ports, so likely not a combination port */
-        if (!port->availability_group) {
-            pa_log_debug("Not switching to port %s, its availability is unknown and it's not in any availability group.", port->name);
-            return;
-        }
-
-        /* For no we only switch the headphone port */
-        if (port->direction != PA_DIRECTION_OUTPUT) {
-            pa_log_debug("Not switching to input port %s, its availability is unknown.", port->name);
-            return;
-        }
-    }
-
     pa_log_debug("Trying to switch to port %s", port->name);
     if (!pp.is_preferred_profile_active) {
         if (try_to_switch_profile(port) < 0) {
@@ -330,6 +304,34 @@ static pa_hook_result_t port_available_hook_callback(pa_core *c, pa_device_port
 
     switch (port->available) {
     case PA_AVAILABLE_UNKNOWN:
+        /* If a port availability became unknown, let's see if it's part of
+         * some availability group. If it is, it is likely to be a headphone
+         * jack that does not have impedance sensing to detect whether what was
+         * plugged in was a headphone, headset or microphone. In desktop
+         * environments that support it, this will trigger a user choice to
+         * select what kind of device was plugged in. However, let's switch to
+         * the headphone port at least, so that we have don't break
+         * functionality for setups that can't trigger this kind of
+         * interaction.
+         *
+         * We should make this configurable so that users can optionally
+         * override the default to a headset or mic. */
+
+        /* Not part of a group of ports, so likely not a combination port */
+        if (!port->availability_group) {
+            pa_log_debug("Not switching to port %s, its availability is unknown and it's not in any availability group.", port->name);
+            break;
+        }
+
+        /* For no we only switch the headphone port */
+        if (port->direction != PA_DIRECTION_OUTPUT) {
+            pa_log_debug("Not switching to input port %s, its availability is unknown.", port->name);
+            break;
+        }
+
+        switch_to_port(port);
+        break;
+
     case PA_AVAILABLE_YES:
         switch_to_port(port);
         break;