core: don't advance to next plugin until needed

Otherwise info->cur_plugin is wrong (and therefore we left uncleared
supports tasks in MMPluginBase) when the port isn't supported by
the plugin, but it's parent modem device was supported by the plugin.
Like when all probing of the port fails but one of it's siblings has
already been claimed by a modem; in this case we just drop the port
(so that no other plugin could try to claim it, because only one
plugin is allowed to handle all a modem's ports) but we still need
to tell the parent modem's plugin to clean up the supports task.

1 files changed, 11 insertions, 6 deletions

diff --git a/src/mm-manager.c b/src/mm-manager.c
index 21b5b582..6a2485eb 100644
--- a/src/mm-manager.c
+++ b/src/mm-manager.c
@@ -564,10 +564,6 @@ supports_callback (MMPlugin *plugin,
     MMPlugin *next_plugin = NULL;
     MMModem *existing;
 
-    info->cur_plugin = info->cur_plugin->next;
-    if (info->cur_plugin)
-        next_plugin = MM_PLUGIN (info->cur_plugin->data);
-
     /* Is this plugin's result better than any one we've tried before? */
     if (level > info->best_level) {
         info->best_level = level;
@@ -610,11 +606,20 @@ supports_callback (MMPlugin *plugin,
             next_plugin = existing_plugin;
         } else
             g_assert_not_reached ();
+    } else {
+        info->cur_plugin = info->cur_plugin->next;
+        if (info->cur_plugin->next)
+            next_plugin = MM_PLUGIN (info->cur_plugin->data);
     }
 
     if (next_plugin) {
-        /* Try the next plugin */
-        try_supports_port (info->manager, next_plugin, existing, info);
+        const char *next_name = mm_plugin_get_name (next_plugin);
+
+        /* Try the next plugin, but don't bother with the Generic plugin if
+         * something already supports this port.
+         */
+        if (!info->best_plugin || strcmp (next_name, MM_PLUGIN_GENERIC_NAME))
+            try_supports_port (info->manager, next_plugin, existing, info);
     } else {
         /* All done; let the best modem grab the port */
         info->done_id = g_idle_add (do_grab_port, info);