[alsa-devel] UCM: check device/modifier status before update

Message ID CAJ4+uhUmHdVZYZFphh71WPOAab_VHpapPKaYunKccNjacSS+HQ@mail.gmail.com
State New
Headers show

Commit Message

Feng Wei Feb. 21, 2012, 8:29 a.m.

Patch

Index: alsa-lib-1.0.25/src/ucm/main.c
===================================================================
--- alsa-lib-1.0.25.orig/src/ucm/main.c 2012-02-21 14:37:25.465485002 +0800
+++ alsa-lib-1.0.25/src/ucm/main.c  2012-02-21 14:38:41.309485042 +0800
@@ -1468,12 +1468,16 @@ 
                            int enable)
 {
         struct use_case_device *device;
+        long status;

         if (uc_mgr->active_verb == NULL)
                 return -ENOENT;
         device = find_device(uc_mgr, uc_mgr->active_verb, device_name, 1);
         if (device == NULL)
                 return -ENOENT;
+        status = device_status(uc_mgr, device_name);
+        if ((!status && !enable) || (status && enable))
+            return 0;
         return set_device(uc_mgr, device, enable);
 }

@@ -1482,6 +1486,7 @@ 
                              int enable)
 {
         struct use_case_modifier *modifier;
+        long status;

         if (uc_mgr->active_verb == NULL)
                 return -ENOENT;
@@ -1489,6 +1494,9 @@ 
         modifier = find_modifier(uc_mgr, uc_mgr->active_verb,
modifier_name, 1);
         if (modifier == NULL)
                 return -ENOENT;
+        status = modifier_status(uc_mgr, modifier_name);
+        if ((!status && !enable) || (status && enable))
+            return 0;
         return set_modifier(uc_mgr, modifier, enable);
 }