From 8cf1b78693664a637ffd78544d4331361fddee8a Mon Sep 17 00:00:00 2001
From: Malcolm Chen <refuhoo@google.com>
Date: Mon, 24 Sep 2018 20:00:08 -0700
Subject: [PATCH] More descriptions on SubscriptionController#setPreferredData

Bug: 115550764
Test: build
Change-Id: I25c3f89a3c3f8e8e6475221885d995bcb5684da4
Merged-In: I25c3f89a3c3f8e8e6475221885d995bcb5684da4
---
 telephony/java/android/telephony/SubscriptionManager.java | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/telephony/java/android/telephony/SubscriptionManager.java b/telephony/java/android/telephony/SubscriptionManager.java
index 3ef80c2efcb51..703cc2bf7688a 100644
--- a/telephony/java/android/telephony/SubscriptionManager.java
+++ b/telephony/java/android/telephony/SubscriptionManager.java
@@ -2148,7 +2148,12 @@ public class SubscriptionManager {
 
     /**
      * Set preferred default data.
-     * Set on which slot default data will be on.
+     * Set on which slot most cellular data will be on.
+     * It's also usually what we set up internet connection on.
+     *
+     * PreferredData overwrites user setting of default data subscription. And it's used
+     * by ANAS or carrier apps to switch primary and CBRS subscription dynamically in multi-SIM
+     * devices.
      *
      * @param slotId which slot is preferred to for cellular data.
      * @hide