From d35e7c34eb970084bad1d6f42a8cf31fbaeca35f Mon Sep 17 00:00:00 2001
From: Madhanraj Chelladurai <mchellad@codeaurora.org>
Date: Mon, 19 Dec 2016 11:23:28 +0530
Subject: [PATCH] Add comments for automitive configuration param and meas
 status

Add comments for automotive configuration parameters and to
masurement status mask

Change-Id: Ia5e16e3044fa15ce15d6ce3c3534898cbd61ef03
CRs-Fixed: 1102724
---
 core/gps_extended_c.h |  6 ++++--
 etc/gps.conf          | 44 +++++++++++++++++++++++++++++++------------
 2 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/core/gps_extended_c.h b/core/gps_extended_c.h
index 55fd03eb..4a356b71 100644
--- a/core/gps_extended_c.h
+++ b/core/gps_extended_c.h
@@ -876,8 +876,10 @@ typedef struct
     */
     uint64_t                        measurementStatus;
     /**< Bitmask indicating SV measurement status.
-         Valid bitmasks: \n
-         @MASK()
+        Valid bitmasks: \n
+        If any MSB bit in 0xFFC0000000000000 DONT_USE is set, the measurement
+        must not be used by the client.
+        @MASK()
     */
     uint16_t                        CNo;
     /**< Carrier to Noise ratio  \n
diff --git a/etc/gps.conf b/etc/gps.conf
index 4b48558f..cc667924 100644
--- a/etc/gps.conf
+++ b/etc/gps.conf
@@ -138,43 +138,63 @@ LPPE_UP_TECHNOLOGY = 0
 # 0: disable
 # 1: enable
 AGPS_CONFIG_INJECT = 1
+
+##################################################
+# GNSS settings for automotive use cases
+# Configurations in following section are
+# specific to automotive use cases, others
+# please do not change, keep the default values
+##################################################
+
 # AP Coarse Timestamp Uncertainty
 ##################################################
 # default : 10
-# or as per clock uncertainty of product
+# AP time stamp uncertainty, until GNSS receiver
+# is able to acquire better timing information
 AP_TIMESTAMP_UNCERTAINTY = 10
 
-#####################################
-# GNSS PPS settings
-#####################################
-#AP DR engine availability status
-# 0 : NO AP DR (default)
-# 1 : AP DR enabled
+##################################################
+# QDR engine availability status
+##################################################
+# 0 : NO QDR (default)
+# 1 : QDR enabled
+# This settings enables QDR Configuration for
+# automotive use case, if enabled then
+# DR_AP_Service needs to be enabled in izat.conf
 #EXTERNAL_DR_ENABLED = 0
 
 #####################################
-#DR_SYNC Pulse Availability
+# DR_SYNC Pulse Availability
 #####################################
 # 0 : DR_SYNC pulse not available (default)
 # 1 : DR_SYNC pulse available
+# This configuration enables the driver to make use
+# of PPS events generated by DR_SYNC pulse
+# Standard Linux PPS driver needs to be enabled
 DR_SYNC_ENABLED = 0
 
 #####################################
-#PPS Device name
+# PPS Device name
 #####################################
 PPS_DEVICENAME = /dev/pps0
 
 #####################################
-#AP Clock Accuracy
+# AP Clock Accuracy
 #####################################
+# Quality of APPS processor clock (in PPM).
+# Value specified is used for calculation of
+# APPS time stamp uncertainty
 AP_CLOCK_PPM = 100
 
 #####################################
-#MAX ms difference to detect missing pulse
+# MAX ms difference to detect missing pulse
 #####################################
+# Specifies time threshold in ms to validate any missing PPS pulses
 MISSING_PULSE_TIME_DELTA = 900
 
 #####################################
-#Propagation time uncertainty
+# Propagation time uncertainty
 #####################################
+# This settings enables time uncertainty propagation
+# logic incase of missing PPS pulse
 PROPAGATION_TIME_UNCERTAINTY = 1