Initial working implementation for Alsa UCM.

Cleanup format for Alsa control GET.

Status: working in progress

5 files changed, 593 insertions, 115 deletions

diff --git a/AlsaSound/CoreBinding/AlsaAfbBinding.c b/AlsaSound/CoreBinding/AlsaCoreBinding.c
index c9bdf30..19a7f3b 100644
--- a/AlsaSound/CoreBinding/AlsaAfbBinding.c
+++ b/AlsaSound/CoreBinding/AlsaCoreBinding.c
@@ -26,7 +26,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 
-#include "AlsaLibMapping.h"
+#include "AlsaCoreBinding.h"
 
 PUBLIC const struct afb_binding_interface *afbIface;   
 
@@ -35,12 +35,17 @@ PUBLIC const struct afb_binding_interface *afbIface;
  */
 static const struct afb_verb_desc_v1 binding_verbs[] = {
   /* VERB'S NAME            SESSION MANAGEMENT          FUNCTION TO CALL         SHORT DESCRIPTION */
-  { .name= "ping"   ,   .session= AFB_SESSION_NONE, .callback= pingtest,       .info= "Ping Binding" },
-  { .name= "getinfo",   .session= AFB_SESSION_NONE, .callback= alsaGetInfo,    .info= "List All/One Sound Cards Info" },
-  { .name= "getctls",    .session= AFB_SESSION_NONE,.callback= alsaGetCtls,    .info= "List All/One Controls from selected sndcard" },
-  { .name= "subscribe", .session= AFB_SESSION_NONE, .callback= alsaSubcribe,   .info= "Subscribe to events from selected sndcard" },
-  { .name= "getcardid", .session= AFB_SESSION_NONE, .callback= alsaGetCardId,  .info= "Get CardId from its short/long name" },
-  { .name= "registerHal",.session= AFB_SESSION_NONE,.callback= alsaRegisterHal,.info= "Register Hal CardName/ApiPrefix" },
+  { .name= "ping"   ,    .session= AFB_SESSION_NONE, .callback= pingtest,        .info= "Ping Binding" },
+  { .name= "getinfo",    .session= AFB_SESSION_NONE, .callback= alsaGetInfo,     .info= "List All/One Sound Cards Info" },
+  { .name= "getctls",    .session= AFB_SESSION_NONE,.callback= alsaGetCtls,      .info= "List All/One Controls from selected sndcard" },
+  { .name= "subscribe",  .session= AFB_SESSION_NONE, .callback= alsaSubcribe,    .info= "Subscribe to events from selected sndcard" },
+  { .name= "getcardid",  .session= AFB_SESSION_NONE, .callback= alsaGetCardId,   .info= "Get CardId from its short/long name" },
+  { .name= "registerHal",.session= AFB_SESSION_NONE,.callback= alsaRegisterHal,  .info= "Register Hal CardName/ApiPrefix" },
+  { .name= "ucmquery",   .session= AFB_SESSION_NONE, .callback= alsaUseCaseQuery,.info= "Use Case Query" },
+  { .name= "ucmset",     .session= AFB_SESSION_NONE, .callback= alsaUseCaseSet,  .info= "Use Case Set" },
+  { .name= "ucmget",     .session= AFB_SESSION_NONE, .callback= alsaUseCaseGet,  .info= "Use Case Get" },
+  { .name= "ucmreset",   .session= AFB_SESSION_NONE, .callback= alsaUseCaseReset,.info= "Use Case Reset to Default" },
+  { .name= "ucmclose",   .session= AFB_SESSION_NONE, .callback= alsaUseCaseClose,.info= "Use Case Close Manager" },
   { .name= NULL } /* marker for end of the array */
 };
 
diff --git a/AlsaSound/CoreBinding/AlsaLibMapping.h b/AlsaSound/CoreBinding/AlsaCoreBinding.h
index a6edd1d..0e5f84a 100644
--- a/AlsaSound/CoreBinding/AlsaLibMapping.h
+++ b/AlsaSound/CoreBinding/AlsaCoreBinding.h
@@ -21,10 +21,25 @@
 
 #include "AudioCommonLib.h"
 
+
+typedef enum {
+    ACTION_SET,
+    ACTION_GET
+} ActionSetGetT;
+
+// generic structure to pass parsed query values
+typedef struct {
+  const char *devid;
+  json_object *jNumIds;
+  int quiet;
+  int count;
+} queryValuesT;
+
 // import from AlsaAfbBinding
 extern const struct afb_binding_interface *afbIface;
+PUBLIC int alsaCheckQuery (struct afb_req request, queryValuesT *queryValues);
 
-// import from AlsaAfbMapping
+// AlseCoreSetGet exports
 PUBLIC void alsaGetInfo (struct afb_req request);
 PUBLIC void alsaGetCtls(struct afb_req request);
 PUBLIC void alsaSetCtrl(struct afb_req request);
@@ -32,6 +47,14 @@ PUBLIC void alsaSubcribe (struct afb_req request);
 PUBLIC void alsaGetCardId (struct afb_req request);
 PUBLIC void alsaRegisterHal (struct afb_req request);
 
+// AlsaUseCase exports
+PUBLIC void alsaUseCaseQuery(struct afb_req request); 
+PUBLIC void alsaUseCaseSet(struct afb_req request); 
+PUBLIC void alsaUseCaseGet(struct afb_req request); 
+PUBLIC void alsaUseCaseClose(struct afb_req request); 
+PUBLIC void alsaUseCaseReset(struct afb_req request); 
+
+
 
 #endif /* ALSALIBMAPPING_H */
 
diff --git a/AlsaSound/CoreBinding/AlsaLibMapping.c b/AlsaSound/CoreBinding/AlsaCtlSetGet.c
index 375d501..a6cd45b 100644
--- a/AlsaSound/CoreBinding/AlsaLibMapping.c
+++ b/AlsaSound/CoreBinding/AlsaCtlSetGet.c
@@ -27,34 +27,31 @@
 #define _GNU_SOURCE  // needed for vasprintf
 
 #include <alsa/asoundlib.h>
-#include "AlsaLibMapping.h"
+#include "AlsaCoreBinding.h"
 #include <systemd/sd-event.h>
 
 
-typedef enum {
-    ACTION_SET,
-    ACTION_GET
-} ActionSetGetT;
 
-// generic structure to pass parsed query values
+// use to store crl numid user request
 typedef struct {
-  const char *devid;
-  json_object *jNumIds;
-  int quiet;
-  int count;
-} queryValuesT;
+    unsigned int numId;
+    json_object *jToken;
+    json_object *jValues;
+    int used;
+} ctlRequestT;
 
 // generic sndctrl event handle hook to event callback when pooling
 typedef struct {
     struct pollfd pfds;
     sd_event_source *src;
-    snd_ctl_t *ctl;
+    snd_ctl_t  *ctlDev;
+    int quiet;
     struct afb_event afbevt;
 } evtHandleT;
 
 typedef struct {
-    int cardid;
     int ucount;
+    int cardId;
     evtHandleT *evtHandle;
 } sndHandleT;
 
@@ -63,23 +60,17 @@ typedef struct {
     char *shortname;    
 }cardRegistryT;
 
-// use to store crl numid user request
-typedef struct {
-    unsigned int numId;
-    json_object *jToken;
-    json_object *jValues;
-    int used;
-} ctlRequestT;
-
-
 cardRegistryT *cardRegistry[MAX_SND_CARD+1];
 
-STATIC void NumidsListParse (queryValuesT *queryValues, ctlRequestT *ctlRequest) {
+PUBLIC void NumidsListParse (queryValuesT *queryValues, ctlRequestT *ctlRequest) {
     json_object *jValues;
     int length;
     
-    for (int idx=0; queryValues->count; idx ++) {                
+    for (int idx=0; idx < queryValues->count; idx ++) {                
         ctlRequest[idx].jToken = json_object_array_get_idx (queryValues->jNumIds, idx);
+        ctlRequest[idx].jValues = NULL;
+        ctlRequest[idx].used=0;
+
         
         switch (json_object_get_type(ctlRequest[idx].jToken)) {
             
@@ -97,7 +88,6 @@ STATIC void NumidsListParse (queryValuesT *queryValues, ctlRequestT *ctlRequest)
                 }
 
                 ctlRequest[idx].numId =json_object_get_int(json_object_array_get_idx (ctlRequest[idx].jToken, 0));
-                ctlRequest[idx].used=0;
 
                 if (length == 2) {
                     jValues = json_object_array_get_idx (ctlRequest[idx].jToken, 1);
@@ -114,33 +104,51 @@ STATIC void NumidsListParse (queryValuesT *queryValues, ctlRequestT *ctlRequest)
     }
 }
 
-STATIC  int alsaCheckQuery (struct afb_req request, queryValuesT *queryValues) {
+PUBLIC  int alsaCheckQuery (struct afb_req request, queryValuesT *queryValues) {
 
     queryValues->devid = afb_req_value(request, "devid");
     if (queryValues->devid == NULL) goto OnErrorExit;
     const char *numids;
+    json_object *jNumIds;
 
     const char *rqtQuiet = afb_req_value(request, "quiet");
     if (!rqtQuiet) queryValues->quiet=99; // default super quiet
     else if (rqtQuiet && ! sscanf (rqtQuiet, "%d", &queryValues->quiet)) {
         json_object *query = afb_req_json(request);
         
-        afb_req_fail_f (request, "quiet-notinteger","Query=%s NumID not integer &numid=%s&", json_object_to_json_string(query), rqtQuiet);
+        afb_req_fail_f (request, "quiet-notinteger","Query=%s Quiet not integer &quiet=%s&", json_object_to_json_string(query), rqtQuiet);
         goto OnErrorExit;
     };
    
     // no NumId is interpreted as ALL for get and error for set
     numids = afb_req_value(request, "numids");
-    if (numids != NULL) {
+    if (numids == NULL) {
         queryValues->count=0;
         goto OnExit;
     }
 
-    queryValues->jNumIds = json_tokener_parse(numids);
-    queryValues->count = json_object_array_length (queryValues->jNumIds);
-    if (queryValues->count <= 0) {
-        afb_req_fail_f (request, "numid-notarray","NumId=%s NumId not valid JSON array", numids);
+    jNumIds = json_tokener_parse(numids);
+    if (!jNumIds) {
+        afb_req_fail_f (request, "numids-notjson","numids=%s not a valid json entry", numids);
         goto OnErrorExit;        
+    };
+    
+    enum json_type jtype= json_object_get_type(jNumIds);
+    switch (jtype) {
+        case json_type_array:
+            queryValues->jNumIds = jNumIds;
+            queryValues->count = json_object_array_length (jNumIds);
+            break;
+            
+        case json_type_int:
+            queryValues->count = 1;
+            queryValues->jNumIds = json_object_new_array ();
+            json_object_array_add (queryValues->jNumIds, jNumIds);
+            break;
+        
+        default:           
+            afb_req_fail_f (request, "numid-notarray","NumId=%s NumId not valid JSON array", numids);
+            goto OnErrorExit;        
     }
 
 OnExit:    
@@ -362,14 +370,12 @@ STATIC  json_object* alsaCardProbe (const char *rqtSndId) {
     snd_ctl_card_info_t *cardinfo;
     int err;
 
-
-    snd_ctl_card_info_alloca(&cardinfo);
-
     if ((err = snd_ctl_open(&handle, rqtSndId, 0)) < 0) {
         INFO (afbIface, "SndCard [%s] Not Found", rqtSndId);
         return NULL;
     }
 
+    snd_ctl_card_info_alloca(&cardinfo);
     if ((err = snd_ctl_card_info(handle, cardinfo)) < 0) {
         snd_ctl_close(handle);
         WARNING (afbIface, "SndCard [%s] info error: %s", rqtSndId, snd_strerror(err));
@@ -390,7 +396,7 @@ STATIC  json_object* alsaCardProbe (const char *rqtSndId) {
         json_object_object_add (ctlDev, "driver"  , json_object_new_string(driver));
         info  = strdup(snd_ctl_card_info_get_longname (cardinfo));
         json_object_object_add (ctlDev, "info" , json_object_new_string (info));
-        INFO (afbIface, "AJG: Soundcard Devid=%-5s Cardid=%-7s Name=%s\n", rqtSndId, devid, info);
+        INFO (afbIface, "AJG: Soundcard Devid=%-5s devid=%-7s Name=%s\n", rqtSndId, devid, info);
     }
 
     // free card handle and return info
@@ -532,8 +538,6 @@ STATIC int alsaGetSingleCtl (snd_ctl_t *ctlDev, snd_ctl_elem_id_t *elemId, ctlRe
     snd_ctl_elem_info_t  *elemInfo;
     int count, idx, err;
 
-    // let's make sure we are processing the right control    
-    if (ctlRequest->numId != snd_ctl_elem_id_get_numid (elemId)) goto OnErrorExit;
          
     // set info event ID and get value
 
@@ -552,6 +556,7 @@ STATIC int alsaGetSingleCtl (snd_ctl_t *ctlDev, snd_ctl_elem_id_t *elemId, ctlRe
     if (snd_ctl_elem_read(ctlDev, elemData) < 0) goto OnErrorExit;
 
     ctlRequest->jValues= json_object_new_object();
+    json_object_object_add (ctlRequest->jValues,"numid" , ctlRequest->jToken);
     if (quiet < 2) json_object_object_add (ctlRequest->jValues,"name" , json_object_new_string(snd_ctl_elem_id_get_name (elemId)));
     if (quiet < 1) json_object_object_add (ctlRequest->jValues,"iface" , json_object_new_string(snd_ctl_elem_iface_name(snd_ctl_elem_id_get_interface(elemId))));
     if (quiet < 3) json_object_object_add (ctlRequest->jValues,"actif", json_object_new_boolean(!snd_ctl_elem_info_is_inactive(elemInfo)));
@@ -658,8 +663,7 @@ PUBLIC void alsaSetGetCtls (struct afb_req request, ActionSetGetT action) {
     unsigned int ctlCount;
     snd_ctl_t *ctlDev;
     snd_ctl_elem_list_t *ctlList;  
-
-    json_object *sndctrls=json_object_new_object();;
+    json_object *sndctls=json_object_new_array();;
     queryValuesT queryValues;
        
     err = alsaCheckQuery (request, &queryValues);
@@ -737,29 +741,38 @@ PUBLIC void alsaSetGetCtls (struct afb_req request, ActionSetGetT action) {
                     err = 1;
             }
             if (err) status++;
-            else json_object_object_add (sndctrls, json_object_to_json_string(ctlRequest[jdx].jToken), ctlRequest[jdx].jValues);
+            else {
+                json_object_array_add (sndctls, ctlRequest[jdx].jValues);
+            }
         }
     }
   
     // if we had error let's add them into response message info
-    json_object *warnings = json_object_new_object();
+    json_object *warnings = json_object_new_array();
     for (int jdx=0; jdx < queryValues.count; jdx++) {
         if (ctlRequest[jdx].used <= 0) {
-           if (ctlRequest[jdx].used == 0) json_object_object_add (warnings, json_object_to_json_string(ctlRequest[jdx].jToken), json_object_new_string ("Does Not Exist"));
-           else json_object_object_add (warnings, json_object_to_json_string(ctlRequest[jdx].jToken), json_object_new_string ("Invalid Value"));
-        }
-        if (ctlRequest[jdx].numId == -1) {
-           json_object_object_add (warnings, json_object_to_json_string(ctlRequest[jdx].jToken), json_object_new_string ("Invalid NumID"));
+            json_object *failctl = json_object_new_object();
+            json_object_object_add (failctl, "numid", ctlRequest[jdx].jToken);
+            if (ctlRequest[jdx].jValues) 
+                json_object_object_add(failctl, "values", ctlRequest[jdx].jValues);
+
+            if (ctlRequest[jdx].numId == -1) json_object_object_add (failctl, "info", json_object_new_string ("Invalid NumID"));
+            else {
+               if (ctlRequest[jdx].used == 0) json_object_object_add (failctl, "info", json_object_new_string ("Does Not Exist"));
+               if (ctlRequest[jdx].used == -1) json_object_object_add (failctl, "info", json_object_new_string ("Invalid Value"));
+            }
+            json_object_array_add (warnings, failctl);
         }
-        // free intermediary object
+        /* WARNING!!!! Check with Jose why following put free jValues
         if (ctlRequest[jdx].jToken) json_object_put(ctlRequest[jdx].jToken);
         if (ctlRequest[jdx].jValues) json_object_put(ctlRequest[jdx].jValues);
+        */
     }
-    if (json_object_object_length(warnings)) warmsg=json_object_to_json_string(warnings);
-    else json_object_put(warnings);
+    
+    if (json_object_array_length(warnings)) warmsg=json_object_to_json_string_ext(warnings, JSON_C_TO_STRING_PLAIN);
   
-    // send response warning if any are passed into info element
-    afb_req_success (request, sndctrls, warmsg);
+    // send response+warning if any
+    afb_req_success (request, sndctls, warmsg);
     snd_ctl_elem_list_clear(ctlList);
     
     OnErrorExit:
@@ -779,15 +792,15 @@ PUBLIC void alsaSetCtls (struct afb_req request) {
 STATIC  int sndCtlEventCB (sd_event_source* src, int fd, uint32_t revents, void* userData) {
     int err;
     evtHandleT *evtHandle = (evtHandleT*)userData; 
-    snd_ctl_event_t *ctlEvent;
-    json_object *ctlEventJson;
+    snd_ctl_event_t *eventId;
+    json_object *ctlEventJ;
     unsigned int mask;
-    int numid;
     int iface;
     int device;
     int subdev;
     const char*devname;
-    int index;  
+    ctlRequestT ctlRequest;
+    snd_ctl_elem_id_t *elemId;
     
     if ((revents & EPOLLHUP) != 0) {
         NOTICE (afbIface, "SndCtl hanghup [car disconnected]");
@@ -795,37 +808,43 @@ STATIC  int sndCtlEventCB (sd_event_source* src, int fd, uint32_t revents, void*
     }
     
     if ((revents & EPOLLIN) != 0)  {
-          
-        snd_ctl_event_alloca(&ctlEvent); // initialise event structure on stack
         
-        err = snd_ctl_read(evtHandle->ctl, ctlEvent);
+        // initialise event structure on stack  
+        snd_ctl_event_alloca(&eventId); 
+        snd_ctl_elem_id_alloca(&elemId);
+        
+        err = snd_ctl_read(evtHandle->ctlDev, eventId);
         if (err < 0) goto OnErrorExit;
         
         // we only process sndctrl element
-        if (snd_ctl_event_get_type(ctlEvent) != SND_CTL_EVENT_ELEM) goto ExitOnSucess;
+        if (snd_ctl_event_get_type(eventId) != SND_CTL_EVENT_ELEM) goto ExitOnSucess;
        
         // we only process value changed events
-        mask = snd_ctl_event_elem_get_mask(ctlEvent);
+        mask = snd_ctl_event_elem_get_mask(eventId);
         if (!(mask & SND_CTL_EVENT_MASK_VALUE)) goto ExitOnSucess;
-       
-        numid  = snd_ctl_event_elem_get_numid(ctlEvent);
-        iface  = snd_ctl_event_elem_get_interface(ctlEvent);
-        device = snd_ctl_event_elem_get_device(ctlEvent);
-        subdev = snd_ctl_event_elem_get_subdevice(ctlEvent);
-        devname= snd_ctl_event_elem_get_name(ctlEvent);
-        index  = snd_ctl_event_elem_get_index(ctlEvent);
         
-        DEBUG(afbIface, "sndCtlEventCB: (%i,%i,%i,%i,%s,%i)", numid, iface, device, subdev, devname, index);
+        snd_ctl_event_elem_get_id (eventId, elemId);
+        
+        err = alsaGetSingleCtl (evtHandle->ctlDev, elemId, &ctlRequest, evtHandle->quiet);
+        if (err) goto OnErrorExit;
 
+        iface  = snd_ctl_event_elem_get_interface(eventId);
+        device = snd_ctl_event_elem_get_device(eventId);
+        subdev = snd_ctl_event_elem_get_subdevice(eventId);
+        devname= snd_ctl_event_elem_get_name(eventId);
+        
         // proxy ctlevent as a binder event        
-        ctlEventJson = json_object_new_object();
-        json_object_object_add(ctlEventJson, "numid"  ,json_object_new_int (numid));
-        json_object_object_add(ctlEventJson, "iface"  ,json_object_new_int (iface));
-        json_object_object_add(ctlEventJson, "device" ,json_object_new_int (device));
-        json_object_object_add(ctlEventJson, "subdev" ,json_object_new_int (subdev));
-        json_object_object_add(ctlEventJson, "devname",json_object_new_string (devname));
-        json_object_object_add(ctlEventJson, "index"  ,json_object_new_int (index));
-        afb_event_push(evtHandle->afbevt, ctlEventJson);
+        ctlEventJ = json_object_new_object();
+        json_object_object_add(ctlEventJ, "device" ,json_object_new_int (device));
+        json_object_object_add(ctlEventJ, "subdev" ,json_object_new_int (subdev));
+        if (evtHandle->quiet < 2) {
+            json_object_object_add(ctlEventJ, "iface"  ,json_object_new_int (iface));
+            json_object_object_add(ctlEventJ, "devname",json_object_new_string (devname));
+        }
+        if (ctlRequest.jValues) (json_object_object_add(ctlEventJ, "values"  ,ctlRequest.jValues));
+        DEBUG(afbIface, "sndCtlEventCB=%s", json_object_get_string(ctlEventJ));
+        afb_event_push(evtHandle->afbevt, ctlEventJ);
+
     }
 
     ExitOnSucess:
@@ -841,31 +860,34 @@ PUBLIC void alsaSubcribe (struct afb_req request) {
     static sndHandleT sndHandles[MAX_SND_CARD];
     evtHandleT *evtHandle;
     snd_ctl_t  *ctlDev;
-    snd_ctl_card_info_t *card_info; 
-    int err, idx, cardid;
-    int idxFree=-1;
+    int err, idx, cardId, idxFree=-1;
+    snd_ctl_card_info_t *cardinfo;
+    queryValuesT queryValues;
+
     
-    const char *devid = afb_req_value(request, "devid");
-    if (devid == NULL) {
-        afb_req_fail_f (request, "devid-missing", "devid=hw:xxx missing");
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+
+
+   // open control interface for devid
+    err = snd_ctl_open(&ctlDev, queryValues.devid, SND_CTL_READONLY);
+    if (err < 0) {
+        ctlDev=NULL;
+        afb_req_fail_f (request, "devid-unknown", "SndCard devid=%s Not Found err=%s", queryValues.devid, snd_strerror(err));
         goto OnErrorExit;
     }
     
-    // open control interface for devid
-    err = snd_ctl_open(&ctlDev, devid, SND_CTL_READONLY);
-    if (err < 0) {
-    afb_req_fail_f (request, "devid-unknown", "SndCard devid=%s Not Found err=%d", devid, err);
-    goto OnErrorExit;
+    snd_ctl_card_info_alloca(&cardinfo);    
+    if ((err = snd_ctl_card_info(ctlDev, cardinfo)) < 0) {        
+        afb_req_fail_f (request, "devid-invalid", "SndCard devid=%s Not Found err=%s", queryValues.devid, snd_strerror(err));
+        goto OnErrorExit;
     }
     
-    // get sound card index use to search existing subscription
-    snd_ctl_card_info_alloca(&card_info);  
-    snd_ctl_card_info(ctlDev, card_info);
-    cardid = snd_ctl_card_info_get_card(card_info);
+    cardId=snd_ctl_card_info_get_card(cardinfo);
     
     // search for an existing subscription and mark 1st free slot
     for (idx= 0; idx < MAX_SND_CARD; idx ++) {
-      if (sndHandles[idx].ucount > 0 && sndHandles[idx].cardid == cardid) {
+      if (sndHandles[idx].ucount > 0 && cardId == sndHandles[idx].cardId) {
          evtHandle= sndHandles[idx].evtHandle;
          break;
       } else if (idxFree == -1) idxFree= idx; 
@@ -877,40 +899,37 @@ PUBLIC void alsaSubcribe (struct afb_req request) {
         // reach MAX_SND_CARD event registration
         if (idxFree == -1) {
             afb_req_fail_f (request, "register-toomany", "Cannot register new event Maxcard==%devent name=%s", idx);
-            snd_ctl_close(ctlDev);
             goto OnErrorExit;            
         } 
         
         evtHandle = malloc (sizeof(evtHandleT));
-        evtHandle->ctl = ctlDev;
+        evtHandle->ctlDev = ctlDev;
+        evtHandle->quiet  = queryValues.quiet;
         sndHandles[idxFree].ucount = 0;
-        sndHandles[idxFree].cardid = cardid;
+        sndHandles[idxFree].cardId = cardId;
         sndHandles[idxFree].evtHandle = evtHandle;
         
         // subscribe for sndctl events attached to devid
-        err = snd_ctl_subscribe_events(evtHandle->ctl, 1);
+        err = snd_ctl_subscribe_events(evtHandle->ctlDev, 1);
         if (err < 0) {
-            afb_req_fail_f (request, "subscribe-fail", "Cannot subscribe events from devid=%s err=%d", devid, err);
-            snd_ctl_close(ctlDev);
+            afb_req_fail_f (request, "subscribe-fail", "Cannot subscribe events from devid=%s err=%d", queryValues.devid, err);
             goto OnErrorExit;
         }
             
         // get pollfd attach to this sound board
-        snd_ctl_poll_descriptors(evtHandle->ctl, &evtHandle->pfds, 1);
+        snd_ctl_poll_descriptors(evtHandle->ctlDev, &evtHandle->pfds, 1);
 
         // register sound event to binder main loop
         err = sd_event_add_io(afb_daemon_get_event_loop(afbIface->daemon), &evtHandle->src, evtHandle->pfds.fd, EPOLLIN, sndCtlEventCB, evtHandle);
         if (err < 0) {
-            afb_req_fail_f (request, "register-mainloop", "Cannot hook events to mainloop devid=%s err=%d", devid, err);
-            snd_ctl_close(ctlDev);
+            afb_req_fail_f (request, "register-mainloop", "Cannot hook events to mainloop devid=%s err=%d", queryValues.devid, err);
             goto OnErrorExit;
         }
 
         // create binder event attached to devid name
-        evtHandle->afbevt = afb_daemon_make_event (afbIface->daemon, devid);
+        evtHandle->afbevt = afb_daemon_make_event (afbIface->daemon, queryValues.devid);
         if (!afb_event_is_valid (evtHandle->afbevt)) {
-            afb_req_fail_f (request, "register-event", "Cannot register new binder event name=%s", devid);
-            snd_ctl_close(ctlDev);
+            afb_req_fail_f (request, "register-event", "Cannot register new binder event name=%s", queryValues.devid);
             goto OnErrorExit; 
         }
 
@@ -921,7 +940,7 @@ PUBLIC void alsaSubcribe (struct afb_req request) {
     // subscribe to binder event    
     err = afb_req_subscribe(request, evtHandle->afbevt);
     if (err != 0) {
-        afb_req_fail_f (request, "register-eventname", "Cannot subscribe binder event name=%s [invalid channel]", devid, err);
+        afb_req_fail_f (request, "register-eventname", "Cannot subscribe binder event name=%s [invalid channel]", queryValues.devid, err);
         goto OnErrorExit;
     }
 
@@ -931,6 +950,7 @@ PUBLIC void alsaSubcribe (struct afb_req request) {
     return;
     
   OnErrorExit:
+        if (ctlDev) snd_ctl_close(ctlDev);            
         return;
 }
 
diff --git a/AlsaSound/CoreBinding/AlsaUseCase.c b/AlsaSound/CoreBinding/AlsaUseCase.c
new file mode 100644
index 0000000..ccea4fa
--- /dev/null
+++ b/AlsaSound/CoreBinding/AlsaUseCase.c
@@ -0,0 +1,430 @@
+/*
+ * AlsaUseCase -- provide low level interface with ALSA lib (extracted from alsa-json-gateway code)
+ * Copyright (C) 2015,2016,2017, Fulup Ar Foll fulup@iot.bzh
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+
+   References:
+      http://www.alsa-project.org/alsa-doc/alsa-lib/group__ucm.html
+      https://www.alsa-project.org/main/index.php/DAPM
+      http://alsa-lib.sourcearchive.com/documentation/1.0.24.1-2/group__Use_ga4332c6bb50481bbdaf21be11551fb930.html
+      https://android.googlesource.com/platform/hardware/qcom/audio/+/jb-mr1-dev/libalsa-intf/alsa_ucm.h
+ 
+   Sample alsaucm commands using /usr/share/alsa/ucm/PandaBoard 
+    - alsaucm  -c PandaBoard list _verbs
+    - alsaucm  -c PandaBoard list _devices/HiFi
+    - alsaucm  -c PandaBoard list _modifiers/HiFi  #need to uncomment modifiers section
+    - alsaucm  -c PandaBoard list TQ/HiFi
+    - alsaucm  -c PandaBoard get TQ/HiFi/Voice
+    - alsaucm  -c PandaBoard get PlaybackPCM//HiFi
+    - alsaucm  -c PandaBoard set _verb HiFi
+    - alsaucm  -c PandaBoard set _verb HiFi _enadev Headset
+    - alsaucm  -c 'HDA Intel PCH'  set _verb HiFi set  _enadev Headphone set _enamod RecordMedia
+    - alsaucm  -c 'HDA Intel PCH'  set _verb HiFi get OutputDspName//
+
+*/
+#define _GNU_SOURCE  // needed for vasprintf
+
+#include <alsa/asoundlib.h>
+#include "AlsaCoreBinding.h"
+#include <alsa/asoundlib.h>
+#include <alsa/use-case.h>
+
+typedef struct {
+     snd_use_case_mgr_t *ucm;
+     int  cardId;
+     char *cardName;
+}    ucmHandleT;
+
+static ucmHandleT ucmHandles[MAX_SND_CARD];
+
+// Cache opened UCM handles 
+STATIC int alsaUseCaseOpen (struct afb_req request, queryValuesT *queryValues, int allowNewMgr) {
+    snd_ctl_t   *ctlDev;
+    snd_ctl_card_info_t *cardinfo;
+    snd_use_case_mgr_t *ucmHandle;
+    const char *cardName;
+    int cardId, idx, idxFree=-1, err;
+    
+    // open control interface for devid
+    err = snd_ctl_open(&ctlDev, queryValues->devid, SND_CTL_READONLY);
+    if (err < 0) {
+        ctlDev=NULL;
+        afb_req_fail_f (request, "devid-unknown", "SndCard devid=[%s] Not Found err=%d", queryValues->devid, err);
+        goto OnErrorExit;
+    }
+    
+    snd_ctl_card_info_alloca(&cardinfo);    
+    if ((err = snd_ctl_card_info(ctlDev, cardinfo)) < 0) {        
+        afb_req_fail_f (request, "devid-invalid", "SndCard devid=[%s] Not Found err=%s", queryValues->devid, snd_strerror(err));
+        goto OnErrorExit;
+    }
+    
+    // search for an existing subscription and mark 1st free slot
+    cardId   = snd_ctl_card_info_get_card(cardinfo); 
+    for (idx= 0; idx < MAX_SND_CARD; idx ++) {
+      if (ucmHandles[idx].ucm != NULL) {
+          if (ucmHandles[idx].cardId == cardId) goto OnSuccessExit;
+      } else if (idxFree == -1) idxFree= idx;
+    };
+    
+    if (!allowNewMgr) {
+        afb_req_fail_f (request, "ucm-nomgr", "SndCard devid=[%s] no exiting UCM manager session", queryValues->devid);
+        goto OnErrorExit;                
+    }
+
+    if (idxFree < 0 && idx == MAX_SND_CARD) {
+        afb_req_fail_f (request, "ucm-toomany", "SndCard devid=[%s] too many open UCM Max=%d", queryValues->devid, MAX_SND_CARD);
+        goto OnErrorExit;        
+    }
+    
+    idx = idxFree;
+    cardName = snd_ctl_card_info_get_name(cardinfo); 
+    err = snd_use_case_mgr_open(&ucmHandle, cardName);
+    if (err) {
+       afb_req_fail_f (request, "ucm-open", "SndCard devid=[%s] name=[%s] No UCM Profile err=%s", queryValues->devid, cardName, snd_strerror(err));
+       goto OnErrorExit; 
+    }
+    ucmHandles[idx].ucm = ucmHandle;
+    ucmHandles[idx].cardId = cardId;        
+    ucmHandles[idx].cardName = strdup(cardName);        
+
+  OnSuccessExit:
+    if (ctlDev) snd_ctl_close(ctlDev);            
+    return idx;
+    
+  OnErrorExit:   
+    if (ctlDev) snd_ctl_close(ctlDev);            
+    return -1;
+}
+      
+
+PUBLIC void alsaUseCaseQuery(struct afb_req request) { 
+    int err, verbCount, ucmIdx;
+    const char **verbList;
+    snd_use_case_mgr_t *ucmHandle;
+    queryValuesT queryValues;
+    json_object *ucmJs;
+    const char *cardName;
+
+    
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+    
+    ucmIdx = alsaUseCaseOpen (request, &queryValues, TRUE);
+    if (ucmIdx < 0) goto OnErrorExit;
+    ucmHandle = ucmHandles [ucmIdx].ucm;
+    cardName  = ucmHandles [ucmIdx].cardName;
+    
+    verbCount = snd_use_case_get_list (ucmHandle, "_verbs", &verbList);
+    if (verbCount < 0) {
+       afb_req_fail_f (request, "ucm-list", "SndCard devid=[%s] name=[%s] No UCM Verbs", queryValues.devid, cardName);
+       goto OnErrorExit; 
+    }
+    
+    ucmJs = json_object_new_array();
+    for (int idx=0; idx < verbCount; idx +=2) {
+        int devCount, modCount, tqCount;
+        const char **devList, **modList, **tqList;
+        json_object *ucmJ = json_object_new_object();
+        char identifier[32];
+        
+        json_object_object_add (ucmJ, "verb", json_object_new_string(verbList[idx]));
+        if (verbList[idx+1]) json_object_object_add (ucmJ, "info", json_object_new_string(verbList[idx+1]));
+        
+        DEBUG (afbIface, "Verb[%d] Action=%s Info=%s", idx, verbList[idx], verbList[idx+1]);
+
+        snprintf (identifier, sizeof(identifier), "_devices/%s", verbList[idx]);
+        devCount = snd_use_case_get_list (ucmHandle, identifier, &devList);
+        if (devCount > 0) {
+            json_object *devsJ = json_object_new_array();
+            
+            for (int jdx=0; jdx < devCount; jdx+=2) {
+                json_object *devJ = json_object_new_object();
+                DEBUG (afbIface, "device[%d] Action=%s Info=%s", jdx, devList[jdx], devList[jdx+1]);
+                json_object_object_add (devJ, "dev", json_object_new_string(devList[jdx]));
+                if (devList[jdx+1]) json_object_object_add (devJ, "info", json_object_new_string(devList[jdx+1]));                
+                json_object_array_add (devsJ, devJ);
+            }
+            json_object_object_add(ucmJ,"devices", devsJ);
+            snd_use_case_free_list(devList, err);
+        }
+        
+        snprintf (identifier, sizeof(identifier), "_modifiers/%s", verbList[idx]);
+        modCount = snd_use_case_get_list (ucmHandle, identifier, &modList);
+        if (modCount > 0) {
+            json_object *modsJ = json_object_new_array();
+            
+            for (int jdx=0; jdx < modCount; jdx+=2) {
+                json_object *modJ = json_object_new_object();
+                DEBUG (afbIface, "modifier[%d] Action=%s Info=%s", jdx, modList[jdx], modList[jdx+1]);
+                json_object_object_add (modJ, "mod", json_object_new_string(modList[jdx]));
+                if (modList[jdx+1]) json_object_object_add (modJ, "info", json_object_new_string(modList[jdx+1]));                
+                json_object_array_add (modsJ, modJ);
+            }
+            json_object_object_add(ucmJ,"modifiers", modsJ);
+            snd_use_case_free_list(modList, err);
+        }
+
+        snprintf (identifier, sizeof(identifier), "TQ/%s", verbList[idx]);
+        tqCount = snd_use_case_get_list (ucmHandle, identifier, &tqList);
+        if (tqCount > 0) {
+            json_object *tqsJ = json_object_new_array();
+            
+            for (int jdx=0; jdx < tqCount; jdx+=2) {
+                json_object *tqJ = json_object_new_object();
+                DEBUG (afbIface, "toneqa[%d] Action=%s Info=%s", jdx, tqList[jdx], tqList[jdx+1]);
+                json_object_object_add (tqJ, "tq", json_object_new_string(tqList[jdx]));
+                if (tqList[jdx+1]) json_object_object_add (tqJ, "info", json_object_new_string(tqList[jdx+1]));                
+                json_object_array_add (tqsJ, tqJ);
+            }
+            json_object_object_add(ucmJ,"tqs", tqsJ);
+            snd_use_case_free_list(tqList, err);
+        }
+        
+        json_object_array_add (ucmJs, ucmJ);
+    }
+    
+    afb_req_success (request, ucmJs, NULL);
+    snd_use_case_free_list(verbList, err);
+        
+  OnErrorExit:
+    return;
+}
+
+STATIC json_object *ucmGetValue (ucmHandleT *ucmHandle, const char *verb, const char *mod, const char *label) {
+    char identifier[80];
+    char *value;
+    int err;
+    json_object *jValue;
+    
+    // handle optional parameters
+    if (!mod)  mod=""; 
+    if (!verb) verb="";
+    
+    if (!label) {
+        NOTICE (afbIface, "ucmGetValue cardname=[%s] value label missing", ucmHandle->cardName);
+        goto OnErrorExit;        
+    }
+    
+    snprintf (identifier, sizeof(identifier), "%s/%s/%s", label, mod, verb);
+    err = snd_use_case_get (ucmHandle->ucm, identifier, (const char**)&value); // Note: value casting is a known "FEATURE" of AlsaUCM API
+    if (err) {
+        DEBUG (afbIface, "ucmGetValue cardname=[%s] identifier=[%s] error=%s", ucmHandle->cardName, identifier, snd_strerror (err));
+        goto OnErrorExit;
+    }
+    
+    // copy value into json object and free string
+    jValue = json_object_new_string (value);
+    free (value);
+    return (jValue);    
+    
+  OnErrorExit:
+    return (NULL);
+}
+
+PUBLIC void alsaUseCaseSet(struct afb_req request) { 
+    int err, ucmIdx;
+    queryValuesT queryValues;
+    json_object *jResponse = json_object_new_object();
+    
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+    
+    ucmIdx = alsaUseCaseOpen (request, &queryValues, TRUE);
+    if (ucmIdx < 0) goto OnErrorExit;
+    
+    snd_use_case_mgr_t *ucmMgr= ucmHandles[ucmIdx].ucm;
+    const char *cardName= ucmHandles[ucmIdx].cardName;
+    
+    const char *verb = afb_req_value(request, "verb");
+    const char *mod  = afb_req_value(request, "mod");
+    const char *dev  = afb_req_value(request, "dev");
+    // Known identifiers: _verb - set current verb = value _enadev - enable given device = value _disdev - disable given device = value _swdev/{old_device} - new_device = value
+
+    if (verb) {
+        err = snd_use_case_set (ucmMgr, "_verb", verb);
+        if (err) {        
+            afb_req_fail_f (request, "ucmset-verb", "SndCard devid=[%s] name=[%s] Invalid UCM verb=[%s] err=%s", queryValues.devid, cardName, verb, snd_strerror(err));
+            goto OnErrorExit;
+        }
+    }
+
+    if (dev) {
+        err = snd_use_case_set (ucmMgr, "_enadev", dev);
+        if (err) {        
+            afb_req_fail_f (request, "ucmset-dev", "SndCard devid=[%s] name=[%s] Invalid UCMverb=[%s] dev=%s err=%s", queryValues.devid, cardName, verb, dev, snd_strerror(err));
+            goto OnErrorExit;
+        }
+    }
+    
+    if (mod) {
+        err = snd_use_case_set (ucmMgr, "_enamod", mod);
+        if (err) {        
+            afb_req_fail_f (request, "ucmset-mod", "SndCard devid=[%s] name=[%s] Invalid UCM verb=[%s] mod=[%s] err=%s", queryValues.devid, cardName, verb, mod, snd_strerror(err));
+            goto OnErrorExit;
+        }
+    }
+    
+    if (queryValues.quiet <= 3) {
+        json_object *jValue;
+
+        jValue = ucmGetValue (&ucmHandles[ucmIdx], verb, dev, "OutputDspName");
+        if (jValue) json_object_object_add (jResponse, "OutputDspName", jValue);
+        
+        jValue = ucmGetValue (&ucmHandles[ucmIdx], verb, dev, "PlaybackPCM");
+        if (jValue) json_object_object_add (jResponse, "PlaybackPCM", jValue);
+
+        jValue = ucmGetValue (&ucmHandles[ucmIdx], verb, mod, "CapturePCM");
+        if (jValue) json_object_object_add (jResponse, "CapturePCM", jValue);
+    }
+    afb_req_success (request, jResponse, NULL);
+ 
+  OnErrorExit:
+    return;
+}
+
+
+PUBLIC void alsaUseCaseGet (struct afb_req request) {
+    int err, ucmIdx, labelCount;
+    queryValuesT queryValues;
+    json_object *jResponse = json_object_new_object();
+    json_object *jWarnings = json_object_new_array();
+    const char *warnings=NULL;
+    
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+    
+    ucmIdx = alsaUseCaseOpen (request, &queryValues, TRUE);
+    if (ucmIdx < 0) goto OnErrorExit;
+    
+    const char *cardName= ucmHandles[ucmIdx].cardName;
+    
+    const char *verb  = afb_req_value(request, "verb");
+    const char *mod   = afb_req_value(request, "mod");
+    const char *dev   = afb_req_value(request, "dev");
+    
+    if (dev && mod) {
+        afb_req_fail_f (request, "ucmget-labels", "SndCard devid=[%s] name=[%s] UCM mod+dev incompatible", queryValues.devid, cardName);
+        goto OnErrorExit;          
+    } 
+    
+    // device selection is handle as a modifier
+    if (dev) mod=dev;
+
+    const char *labels = afb_req_value(request, "values");
+    if (!labels) {
+        afb_req_fail_f (request, "ucmget-labels", "SndCard devid=[%s] name=[%s] UCM values name missing", queryValues.devid, cardName);
+        goto OnErrorExit;  
+    } 
+    
+    json_object *jLabels = json_tokener_parse(labels);
+    if (!jLabels) {
+        afb_req_fail_f (request, "ucmget-notjson","labels=%s not a valid json entry", labels);
+        goto OnErrorExit;        
+    };
+    
+    enum json_type jtype= json_object_get_type(jLabels);
+    switch (jtype) {
+        json_object *jTmp;
+        
+        case json_type_array:
+            labelCount = json_object_array_length (jLabels);
+            break;
+            
+        case json_type_string:
+            jTmp = json_object_new_array ();
+            labelCount = 1;
+            json_object_array_add (jTmp, jLabels);
+            jLabels=jTmp;
+            break;
+        
+        default:           
+            afb_req_fail_f (request, "ucmget-notarray","labels=%s not valid JSON array", labels);
+            goto OnErrorExit;        
+    }
+
+    for (int idx=0; idx < labelCount; idx++) {
+        json_object *jValue, *jLabel;
+        const char *label ;
+        
+        jLabel= json_object_array_get_idx (jLabels, idx);
+        label= json_object_get_string (jLabel);
+        jValue = ucmGetValue (&ucmHandles[ucmIdx], verb, mod, label);
+        if (jValue) json_object_object_add (jResponse, label, jValue);
+        else {
+            json_object_array_add (jWarnings, jLabel);
+        }
+    }
+    
+    // use info section to notified not found values label
+    if (json_object_array_length (jWarnings) > 0) {
+       json_object *jTmp =  json_object_new_object ();
+       json_object_object_add (jTmp, "no-context", jWarnings);
+       warnings= json_object_to_json_string (jTmp);
+    }
+    afb_req_success (request, jResponse, warnings);
+    
+  OnErrorExit:
+    return;        
+}
+    
+
+PUBLIC void alsaUseCaseReset (struct afb_req request) {
+    int err, ucmIdx;
+    queryValuesT queryValues;
+    
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+    
+    ucmIdx = alsaUseCaseOpen (request, &queryValues, FALSE);
+    if (ucmIdx < 0) goto OnErrorExit;
+    
+    err= snd_use_case_mgr_reset (ucmHandles[ucmIdx].ucm);
+    if (err) {
+        afb_req_fail_f (request, "ucmreset-fail","devid=%s Card Name=%s", queryValues.devid, ucmHandles[ucmIdx].cardName);
+        goto OnErrorExit;        
+    }
+    
+    afb_req_success (request, NULL, NULL);
+    
+  OnErrorExit:
+    return;        
+}
+    
+PUBLIC void alsaUseCaseClose (struct afb_req request) {
+    int err, ucmIdx;
+    queryValuesT queryValues;
+    
+    err = alsaCheckQuery (request, &queryValues);
+    if (err) goto OnErrorExit;
+    
+    ucmIdx = alsaUseCaseOpen (request, &queryValues, FALSE);
+    if (ucmIdx < 0) goto OnErrorExit;
+    
+    err= snd_use_case_mgr_close (ucmHandles[ucmIdx].ucm);
+    if (err) {
+        afb_req_fail_f (request, "ucmreset-close","devid=%s Card Name=%s", queryValues.devid, ucmHandles[ucmIdx].cardName);
+        goto OnErrorExit;        
+    }
+    
+    // do not forget to release sound card name string
+    free (ucmHandles[ucmIdx].cardName);
+    
+    afb_req_success (request, NULL, NULL);
+    
+  OnErrorExit:
+    return;        
+}
+    
+
diff --git a/AlsaSound/CoreBinding/CMakeLists.txt b/AlsaSound/CoreBinding/CMakeLists.txt
index 0475e72..e14432e 100644
--- a/AlsaSound/CoreBinding/CMakeLists.txt
+++ b/AlsaSound/CoreBinding/CMakeLists.txt
@@ -22,7 +22,7 @@ INCLUDE_DIRECTORIES(${include_dirs})
 ##################################################
 # AlsaBinding
 ##################################################
-ADD_LIBRARY(alsacore-afb MODULE AlsaAfbBinding.c AlsaLibMapping.c)
+ADD_LIBRARY(alsacore-afb MODULE AlsaCoreBinding.c AlsaCtlSetGet.c AlsaUseCase.c)
 
 SET_TARGET_PROPERTIES(alsacore-afb PROPERTIES
 	PREFIX ""