From a7a6ae4be87ee9178905ab784d84a4c0a8303f9b Mon Sep 17 00:00:00 2001
From: fulup <fulup.arfoll@iot.bzh>
Date: Sun, 23 Jul 2017 01:23:37 +0200
Subject: Added TLV->DBscale into HAL control 1st Working version of HAL
 ctl-get with TLV Cleanup HTML5 test pages WIP Only

---
 HAL-afb/HAL-interface/hal-volmap.c | 96 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)
 create mode 100644 HAL-afb/HAL-interface/hal-volmap.c

(limited to 'HAL-afb/HAL-interface/hal-volmap.c')

diff --git a/HAL-afb/HAL-interface/hal-volmap.c b/HAL-afb/HAL-interface/hal-volmap.c
new file mode 100644
index 0000000..de99974
--- /dev/null
+++ b/HAL-afb/HAL-interface/hal-volmap.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2016 "IoT.bzh"
+ * Author 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: 
+ *   alsa-util/amixer.c + alsa-lib/simple.c
+ */
+
+#define _GNU_SOURCE  // needed for vasprintf
+#include <math.h>
+#include "hal-interface.h"
+
+
+typedef enum {  
+   DB_NORMALIZE_LINEAR,
+   DB_NORMALIZE_MATH,           
+} enumRandeModeDB_T;
+
+// Return Value express from 0-100%
+STATIC int dbNormalizeVal (enumRandeModeDB_T normaliseMode, const alsaHalDBscaleT *dbscale, int value) {
+    double normalized, min_norm;
+    
+    // To get real DB from TLV DB values should be divided by 100
+    switch (normaliseMode) {
+        case DB_NORMALIZE_LINEAR:
+            normalized = ((double)(value-dbscale->min)/(double)(dbscale->max-dbscale->min))*100;
+            break;
+            
+        case  DB_NORMALIZE_MATH:
+            normalized = exp10((double)(value - dbscale->max) / 6000.0);
+            if (dbscale->min != SND_CTL_TLV_DB_GAIN_MUTE) {
+                    min_norm = exp10((double)(dbscale->min - dbscale->max) / 6000.0);
+                    normalized = (normalized - min_norm) / (1 - min_norm);
+            }
+            break;
+            
+        default:
+            normalized=0;            
+    }
+    
+    return (int)round(normalized*100);   
+}
+
+// HAL normalise volume values to 0-100%
+PUBLIC struct json_object *GetNormaliseVolume(const alsaHalCtlMapT *halCtls,  struct json_object *valuesJ) {
+    int useNormalizeDB;
+    
+    // If not valid db_scale let's use raw_scale
+    if (!halCtls->dbscale || (halCtls->dbscale->min >= halCtls->dbscale->max)) {
+       
+        // dbscale is invalid let's try raw range
+        if (halCtls->minval >= halCtls->maxval) goto ExitOnError;
+        
+        // Use Raw Scale Model
+        useNormalizeDB= 0;
+        
+    } else { // db_scale looks OK let's use it
+        if ((halCtls->dbscale->max - halCtls->dbscale->min) <= MAX_LINEAR_DB_SCALE * 100) useNormalizeDB= DB_NORMALIZE_LINEAR;
+        else useNormalizeDB =  DB_NORMALIZE_MATH;
+            
+    }
+    
+    // loop on values to normalise
+    int length = json_object_array_length(valuesJ);   
+    json_object *normalisedJ= json_object_new_array();
+    for (int idx=0; idx <length; idx++) {
+        json_object *valueJ = json_object_array_get_idx (valuesJ, idx);
+        int value = json_object_get_int(valueJ);
+               
+        // If Integer scale to 0/100
+        if (halCtls->type == SND_CTL_ELEM_TYPE_INTEGER) {
+            if (useNormalizeDB) value = dbNormalizeVal (useNormalizeDB, halCtls->dbscale, value);
+            else value = 100* (value - halCtls->minval) / (halCtls->maxval - halCtls->minval);
+        } 
+        
+        json_object_array_add(normalisedJ, json_object_new_int(value));  
+    }
+    
+    return (normalisedJ);
+    
+  ExitOnError:
+        return NULL;
+}
+    
\ No newline at end of file
-- 
cgit 1.2.3-korg