usb: Add ability to prompt user about what to do upon usb insertion

 v3: Add in config option
 v4: Bugfixes
 v5: Force a redraw upon exiting
 v6: keypress-in-chargeonly mode enables mass storage (and vice versa)
 v7: Fix bootloader builds
 v8: Update manual, and have bootloader respect keypresses
 v9: Change default to mass storage (ie no change in behavior)

 todo:
  * test-build dx50/dx90
  * Switch from yes/no to proper menu?
  * prevent WPS progress bar from drawing over us

Change-Id: I82e0ccb08497b7a5aa756ce77f1332ee963703a7

...

Change-Id: I7946cf240b18a4fa8ace5e25e1eb6e97b8b12d7c

30 files changed, 224 insertions, 156 deletions

diff --git a/apps/lang/bulgarian.lang b/apps/lang/bulgarian.lang
index 7116e06927..ad65efd7e7 100644
--- a/apps/lang/bulgarian.lang
+++ b/apps/lang/bulgarian.lang
@@ -13134,7 +13134,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -13205,7 +13205,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13259,7 +13259,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13299,7 +13299,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
diff --git a/apps/lang/chinese-simp.lang b/apps/lang/chinese-simp.lang
index 73884e567a..e3de41e636 100644
--- a/apps/lang/chinese-simp.lang
+++ b/apps/lang/chinese-simp.lang
@@ -13109,7 +13109,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13129,7 +13129,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13149,7 +13149,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13169,7 +13169,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/chinese-trad.lang b/apps/lang/chinese-trad.lang
index fa3434a85e..6b8faee6a5 100644
--- a/apps/lang/chinese-trad.lang
+++ b/apps/lang/chinese-trad.lang
@@ -11608,7 +11608,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -11628,7 +11628,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -11648,7 +11648,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -11668,7 +11668,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/deutsch.lang b/apps/lang/deutsch.lang
index 9efcedb6d7..a21b2811d4 100644
--- a/apps/lang/deutsch.lang
+++ b/apps/lang/deutsch.lang
@@ -13032,7 +13032,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13052,7 +13052,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13072,7 +13072,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13092,7 +13092,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/english-us.lang b/apps/lang/english-us.lang
index b9a697b779..141c148db2 100644
--- a/apps/lang/english-us.lang
+++ b/apps/lang/english-us.lang
@@ -12873,7 +12873,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12972,7 +12972,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -13702,7 +13702,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13784,7 +13784,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index 48ffd2af25..d0b088cf76 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -12769,71 +12769,59 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
-    *: none
-    ibassodx50,ibassodx90: "USB Mode"
+    *: "USB Mode"
   </source>
   <dest>
-    *: none
-    ibassodx50,ibassodx90: "USB Mode"
+    *: "USB Mode"
   </dest>
   <voice>
-    *: none
-    ibassodx50,ibassodx90: "USB Mode"
+    *: "USB Mode"
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
-    *: none
-    ibassodx50,ibassodx90: "Mass Storage"
+    *: "Mass Storage"
   </source>
   <dest>
-    *: none
-    ibassodx50,ibassodx90: "Mass Storage"
+    *: "Mass Storage"
   </dest>
   <voice>
-    *: none
-    ibassodx50,ibassodx90: "Mass Storage"
+    *: "Mass Storage"
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
-    *: none
-    ibassodx50,ibassodx90: "Charge Only"
+    *: "Charge Only"
   </source>
   <dest>
-    *: none
-    ibassodx50,ibassodx90: "Charge Only"
+    *: "Charge Only"
   </dest>
   <voice>
-    *: none
-    ibassodx50,ibassodx90: "Charge Only"
+    *: "Charge Only"
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
-    *: none
-    ibassodx50,ibassodx90: "Android Debug Bridge"
+    *: "Android Debug Bridge"
   </source>
   <dest>
-    *: none
-    ibassodx50,ibassodx90: "Android Debug Bridge"
+    *: "Android Debug Bridge"
   </dest>
   <voice>
-    *: none
-    ibassodx50,ibassodx90: "Android Debug Bridge"
+    *: "Android Debug Bridge"
   </voice>
 </phrase>
 <phrase>
@@ -16344,3 +16332,17 @@
     *: "Browse"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_ENTER_USB_STORAGE_MODE_QUERY
+  desc: upon plugging in USB
+  user: core
+  <source>
+    *: "Enter USB mass storage mode?"
+  </source>
+  <dest>
+    *: "Enter USB mass storage mode?"
+  </dest>
+  <voice>
+    *: "Enter USB mass storage mode?"
+  </voice>
+</phrase>
diff --git a/apps/lang/francais.lang b/apps/lang/francais.lang
index 8763c26d54..9baf25bee6 100644
--- a/apps/lang/francais.lang
+++ b/apps/lang/francais.lang
@@ -12461,7 +12461,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -12662,7 +12662,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -12682,7 +12682,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -12750,7 +12750,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
diff --git a/apps/lang/greek.lang b/apps/lang/greek.lang
index 54381273d2..1a83188592 100644
--- a/apps/lang/greek.lang
+++ b/apps/lang/greek.lang
@@ -11641,7 +11641,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -12225,7 +12225,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12798,7 +12798,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13436,7 +13436,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/italiano.lang b/apps/lang/italiano.lang
index 22fad246a4..1d28810562 100644
--- a/apps/lang/italiano.lang
+++ b/apps/lang/italiano.lang
@@ -12414,7 +12414,7 @@ desc: deprecated
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -12566,7 +12566,7 @@ desc: deprecated
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -12631,7 +12631,7 @@ desc: deprecated
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12676,7 +12676,7 @@ desc: deprecated
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/japanese.lang b/apps/lang/japanese.lang
index 93db2fa3bb..723d4db175 100644
--- a/apps/lang/japanese.lang
+++ b/apps/lang/japanese.lang
@@ -12936,7 +12936,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -12956,7 +12956,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13083,7 +13083,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13247,7 +13247,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/magyar.lang b/apps/lang/magyar.lang
index 7493b9dfe5..f00b9b857f 100644
--- a/apps/lang/magyar.lang
+++ b/apps/lang/magyar.lang
@@ -11844,7 +11844,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12522,7 +12522,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13163,7 +13163,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13197,7 +13197,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/nederlands.lang b/apps/lang/nederlands.lang
index 3eefb29bbb..3aa7a64c2f 100644
--- a/apps/lang/nederlands.lang
+++ b/apps/lang/nederlands.lang
@@ -13316,7 +13316,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13336,7 +13336,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13446,7 +13446,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13466,7 +13466,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/norsk.lang b/apps/lang/norsk.lang
index f6945d41c1..dbe5422e59 100644
--- a/apps/lang/norsk.lang
+++ b/apps/lang/norsk.lang
@@ -11152,7 +11152,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -11471,7 +11471,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -11646,7 +11646,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -12333,7 +12333,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
diff --git a/apps/lang/polski.lang b/apps/lang/polski.lang
index 7529d200d4..10399b14c8 100644
--- a/apps/lang/polski.lang
+++ b/apps/lang/polski.lang
@@ -12517,7 +12517,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -12551,7 +12551,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12619,7 +12619,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -12636,7 +12636,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/portugues.lang b/apps/lang/portugues.lang
index ff72cf0cb8..e511f3bfdd 100644
--- a/apps/lang/portugues.lang
+++ b/apps/lang/portugues.lang
@@ -13146,7 +13146,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13237,7 +13237,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13257,7 +13257,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13328,7 +13328,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/lang/russian.lang b/apps/lang/russian.lang
index 769c1fb8c6..842ae14764 100644
--- a/apps/lang/russian.lang
+++ b/apps/lang/russian.lang
@@ -13083,7 +13083,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13103,7 +13103,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13137,7 +13137,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -13236,7 +13236,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
diff --git a/apps/lang/slovak.lang b/apps/lang/slovak.lang
index 058e2ce563..4468ac392d 100644
--- a/apps/lang/slovak.lang
+++ b/apps/lang/slovak.lang
@@ -12578,7 +12578,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12612,7 +12612,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -12629,7 +12629,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -12663,7 +12663,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
diff --git a/apps/lang/srpski.lang b/apps/lang/srpski.lang
index 32ce847167..e7de54aadc 100644
--- a/apps/lang/srpski.lang
+++ b/apps/lang/srpski.lang
@@ -12597,7 +12597,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -12628,7 +12628,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -12752,7 +12752,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -12845,7 +12845,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
diff --git a/apps/lang/svenska.lang b/apps/lang/svenska.lang
index c0cc384554..bbf0636d37 100644
--- a/apps/lang/svenska.lang
+++ b/apps/lang/svenska.lang
@@ -12990,7 +12990,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13089,7 +13089,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13199,7 +13199,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -13453,7 +13453,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
diff --git a/apps/lang/turkce.lang b/apps/lang/turkce.lang
index 24a816798f..d9de1e1495 100644
--- a/apps/lang/turkce.lang
+++ b/apps/lang/turkce.lang
@@ -4663,7 +4663,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
@@ -10884,7 +10884,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -11262,7 +11262,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13413,7 +13413,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
diff --git a/apps/lang/vlaams.lang b/apps/lang/vlaams.lang
index c738af1638..2e1989f0b1 100644
--- a/apps/lang/vlaams.lang
+++ b/apps/lang/vlaams.lang
@@ -13278,7 +13278,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_MASS_STORAGE
+  id: LANG_USB_MODE_MASS_STORAGE
   desc: in Settings -> General -> System -> USB Mode: Mass Storage
   user: core
   <source>
@@ -13298,7 +13298,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE
+  id: LANG_USB_MODE
   desc: in Settings -> General -> System -> USB Mode
   user: core
   <source>
@@ -13408,7 +13408,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_CHARGE
+  id: LANG_USB_MODE_CHARGE
   desc: in Settings -> General -> System -> USB Mode: Charge Only
   user: core
   <source>
@@ -13428,7 +13428,7 @@
   </voice>
 </phrase>
 <phrase>
-  id: LANG_IBASSO_USB_MODE_ADB
+  id: LANG_USB_MODE_ADB
   desc: in Settings -> General -> System -> USB Mode: Android Debug Bridge
   user: core
   <source>
diff --git a/apps/menus/settings_menu.c b/apps/menus/settings_menu.c
index 9275ff10d6..159ad08a44 100644
--- a/apps/menus/settings_menu.c
+++ b/apps/menus/settings_menu.c
@@ -266,6 +266,9 @@ MAKE_MENU(battery_menu, ID2P(LANG_BATTERY_MENU), 0, Icon_NOICON,
             &usb_charging,
 #endif
          );
+#ifdef HAVE_USB_POWER
+MENUITEM_SETTING(usb_mode, &global_settings.usb_mode, NULL);
+#endif
 /* Disk */
 #ifdef HAVE_DISK_STORAGE
 MENUITEM_SETTING(disk_spindown, &global_settings.disk_spindown, NULL);
@@ -446,6 +449,8 @@ MAKE_MENU(system_menu, ID2P(LANG_SYSTEM),
 
 #if defined(DX50) || defined(DX90)
             &governor,
+#endif
+#ifdef HAVE_USB_POWER
             &usb_mode,
 #endif
          );
diff --git a/apps/settings.h b/apps/settings.h
index ec66553660..f9deae1ebe 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -822,6 +822,8 @@ struct user_settings
 
 #if defined(DX50) || defined(DX90)
     int governor;
+#endif
+#ifdef HAVE_USB_POWER
     int usb_mode;
 #endif
 };
diff --git a/apps/settings_list.c b/apps/settings_list.c
index 47384bdbed..17720b5145 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -2156,17 +2156,31 @@ const struct settings_list settings[] = {
                    "Interactive",
                    "Powersave",
                    "Performance"),
+#endif
+#if defined(HAVE_USB_POWER) && !defined(USB_NONE) && !defined(SIMULATOR)
     CHOICE_SETTING(0,
                    usb_mode,
-                   LANG_IBASSO_USB_MODE,
+                   LANG_USB_MODE,
                    USB_MODE_MASS_STORAGE,
                    "usb mode",
-                   "mass storage,charge,adb",
-                   ibasso_set_usb_mode,
+                   "ask,mass storage,charge"
+#if defined(DX50) || defined(DX90)
+                   ",adb"
+#endif
+                   ,
+                   usb_set_mode,
+#if defined(DX50) || defined(DX90)
+                   4,
+#else
                    3,
-                   ID2P(LANG_IBASSO_USB_MODE_MASS_STORAGE),
-                   ID2P(LANG_IBASSO_USB_MODE_CHARGE),
-                   ID2P(LANG_IBASSO_USB_MODE_ADB)),
+#endif
+                   ID2P(LANG_ASK),
+                   ID2P(LANG_USB_MODE_MASS_STORAGE),
+                   ID2P(LANG_USB_MODE_CHARGE)
+#if defined(DX50) || defined(DX90)
+                   ,ID2P(LANG_USB_MODE_ADB)
+#endif
+            ),
 #endif
 };
 
diff --git a/firmware/export/usb.h b/firmware/export/usb.h
index b7b846d5b3..edc37bd5b6 100644
--- a/firmware/export/usb.h
+++ b/firmware/export/usb.h
@@ -131,6 +131,15 @@ enum
 #endif
 };
 
+/* Supported usb modes. */
+enum
+{
+    USB_MODE_ASK = 0,
+    USB_MODE_MASS_STORAGE,
+    USB_MODE_CHARGE,
+    USB_MODE_ADB
+};
+
 #ifdef HAVE_USB_POWER
 /*allow people to define this in config-target.h if they need it*/
 #if !defined(USBPOWER_BTN_IGNORE)
@@ -215,6 +224,7 @@ void usb_charging_maxcurrent_change(int maxcurrent);
 /* returns the maximum allowed USB current, based on USB charging mode and state */
 int usb_charging_maxcurrent(void);
 #endif /* HAVE_USB_CHARGING_ENABLE */
+void usb_set_mode(int mode);
 #endif /* HAVE_USB_POWER */
 #ifdef HAVE_USBSTACK
 /* USB driver call this function to notify that a transfer has completed */
diff --git a/firmware/target/hosted/ibasso/usb-ibasso.c b/firmware/target/hosted/ibasso/usb-ibasso.c
index e1b134e545..9af932f94f 100644
--- a/firmware/target/hosted/ibasso/usb-ibasso.c
+++ b/firmware/target/hosted/ibasso/usb-ibasso.c
@@ -60,11 +60,9 @@ static void usb_enable_mass_storage(void)
     DEBUGF("ERROR %s: No command processor available.", __func__);
 }
 
-
 /* Default at boot not known. */
 static int _last_usb_mode = -1;
 
-
 void ibasso_set_usb_mode(int mode)
 {
     DEBUGF("DEBUG %s: _last_usb_mode: %d, mode: %d.", __func__, _last_usb_mode, mode);
diff --git a/firmware/target/hosted/ibasso/usb-ibasso.h b/firmware/target/hosted/ibasso/usb-ibasso.h
index f509d43038..6cd31134b6 100644
--- a/firmware/target/hosted/ibasso/usb-ibasso.h
+++ b/firmware/target/hosted/ibasso/usb-ibasso.h
@@ -25,30 +25,10 @@
 #ifndef _USB_DX50_H_
 #define _USB_DX50_H_
 
-
-/* Supported usb modes. */
-enum ibasso_usb_mode
-{
-    /*
-        USB mass storage mode. On USB connection, Rockbox will terminate and the internel and
-        external storage gets exported to the connected client.
-    */
-    USB_MODE_MASS_STORAGE = 0,
-
-    /*
-        Actually the same, since we to not have proper USB detection.
-        Starts the adb server and enables adb connection over USB. Rockbox will continue to run.
-    */
-    USB_MODE_CHARGE,
-    USB_MODE_ADB
-};
-
-
 /*
     Set the usb mode.
     mode: ibasso_usb_mode
 */
 void ibasso_set_usb_mode(int mode);
 
-
 #endif
diff --git a/firmware/usb.c b/firmware/usb.c
index e0c0c45865..8443ffed3a 100644
--- a/firmware/usb.c
+++ b/firmware/usb.c
@@ -42,6 +42,14 @@
 #include "logf.h"
 #include "screendump.h"
 
+#ifndef BOOTLOADER
+#include "misc.h"
+#include "gui/yesno.h"
+#include "settings.h"
+#include "lang_enum.h"
+#include "gui/skin_engine/skin_engine.h"
+#endif
+
 /* Conditions under which we want the entire driver */
 #if !defined(BOOTLOADER) || \
      (defined(HAVE_USBSTACK) && defined(HAVE_BOOTLOADER_USB_MODE)) || \
@@ -71,7 +79,7 @@ static int usb_mmc_countdown = 0;
 #ifndef USB_EXTRA_STACK
 #   define USB_EXTRA_STACK 0x0 /*Define in firmware/export/config/[target].h*/
 #endif
-static long usb_stack[(DEFAULT_STACK_SIZE + DUMP_BMP_LINESIZE + USB_EXTRA_STACK)/sizeof(long)];
+static long usb_stack[(DEFAULT_STACK_SIZE*2 + DUMP_BMP_LINESIZE + USB_EXTRA_STACK)/sizeof(long)];
 static const char usb_thread_name[] = "usb";
 static unsigned int usb_thread_entry = 0;
 static bool usb_monitor_enabled = false;
@@ -87,7 +95,8 @@ static bool usb_host_present = false;
 static int usb_num_acks_to_expect = 0;
 static long usb_last_broadcast_tick = 0;
 #ifdef HAVE_USB_POWER
-static bool usb_charging_only = false;
+static int usb_mode = USB_MODE_ASK;
+static int new_usbmode = USB_MODE_ASK;
 #endif
 
 static int usb_release_exclusive_storage(void);
@@ -130,17 +139,15 @@ static inline bool usb_do_screendump(void)
     return false;
 }
 
-/* Power (charging-only) button */
-static inline void usb_detect_charging_only(bool detect)
-{
 #ifdef HAVE_USB_POWER
-    if (detect)
-        detect = button_status() & ~USBPOWER_BTN_IGNORE;
-
-    usb_charging_only = detect;
+void usb_set_mode(int mode)
+{
+    usb_mode = mode;
+#if defined(DX50) || defined(DX90)
+    ibasso_set_usb_mode(mode);
 #endif
-    (void)detect;
 }
+#endif
 
 #ifdef USB_FIREWIRE_HANDLING
 static inline bool usb_reboot_button(void)
@@ -201,7 +208,7 @@ static inline bool usb_configure_drivers(int for_state)
         usb_attach(); /* Powered only: attach now. */
         break;
         /* USB_POWERED: */
-    
+
     case USB_INSERTED:
 #ifdef USB_ENABLE_STORAGE
         usb_core_enable_driver(USB_DRIVER_MASS_STORAGE, true);
@@ -372,7 +379,7 @@ static void usb_set_host_present(bool present)
     }
 
 #ifdef HAVE_USB_POWER
-    if (usb_charging_only)
+    if (new_usbmode == USB_MODE_CHARGE || new_usbmode == USB_MODE_ADB)
     {
         /* Only charging is desired */
         usb_configure_drivers(USB_POWERED);
@@ -464,9 +471,49 @@ static void NORETURN_ATTR usb_thread(void)
             }
 
             usb_state = USB_POWERED;
+
             usb_stack_enable(true);
 
-            usb_detect_charging_only(true);
+            /* Power (charging-only) button */
+#ifdef HAVE_USB_POWER
+            switch (usb_mode) {
+            case USB_MODE_CHARGE:
+            case USB_MODE_ADB:
+                if (button_status() & ~USBPOWER_BTN_IGNORE)
+                    new_usbmode = USB_MODE_MASS_STORAGE;
+                break;
+#ifndef BOOTLOADER
+            case USB_MODE_ASK:
+                new_usbmode = USB_MODE_ASK;
+                break;
+#endif
+            default:
+            case USB_MODE_MASS_STORAGE:
+                if (button_status() & ~USBPOWER_BTN_IGNORE)
+                    new_usbmode = USB_MODE_CHARGE;
+                    break;
+            }
+
+#ifndef BOOTLOADER
+            if (new_usbmode == USB_MODE_ASK)
+            {
+                push_current_activity(ACTIVITY_USBSCREEN);
+                if (yesno_pop(ID2P(LANG_ENTER_USB_STORAGE_MODE_QUERY)))
+                    new_usbmode = USB_MODE_MASS_STORAGE;
+                else
+                    new_usbmode = USB_MODE_CHARGE;
+                pop_current_activity();
+                /* Force full redraw */
+//                queue_post(&button_queue, BUTTON_REDRAW, 0);
+// Alternative approach, as above is supposedly inadequate by design.
+                FOR_NB_SCREENS(i)
+                {
+                    struct screen *screen = &screens[i];
+                    screen->set_viewport(NULL);
+                }
+            }
+#endif
+#endif
 
 #ifndef USB_DETECT_BY_REQUEST
             usb_set_host_present(true);
@@ -493,8 +540,10 @@ static void NORETURN_ATTR usb_thread(void)
                 usb_slave_mode(false);
 
             usb_state = USB_EXTRACTED;
+#ifdef HAVE_USB_POWER
+            new_usbmode = usb_mode;
+#endif
 
-            usb_detect_charging_only(false);
             usb_set_host_present(false);
             break;
             /* USB_EXTRACTED: */
@@ -597,7 +646,7 @@ static void usb_tick(void)
 #ifdef USB_FIREWIRE_HANDLING
     static int firewire_countdown = -1;
     static int last_firewire_status = false;
-#endif    
+#endif
 
     if(usb_monitor_enabled)
     {
@@ -814,4 +863,3 @@ void usb_wait_for_disconnect(struct event_queue *q)
    (void)q;
 }
 #endif /* USB_NONE */
-
diff --git a/manual/configure_rockbox/system_options.tex b/manual/configure_rockbox/system_options.tex
index 4faeafb895..f9e09a91b1 100755
--- a/manual/configure_rockbox/system_options.tex
+++ b/manual/configure_rockbox/system_options.tex
@@ -851,6 +851,12 @@ therefore result in better runtime.
     }}
     \end{description}
 }
+\opt{usb_power}{
+  \subsection{USB Mode}
+    This controls what happens with the \dap{}'s USB port is connected.
+    \setting{Charge Only} and \setting{Mass Storage} will automatically enter
+    that mode, and \setting{Ask} will prompt the user each time.
+}
 \opt{multidrive_usb}{
   \subsection{USB Hide Internal Drive}
     If this option is turned \setting{On}, the internal storage drive will not
diff --git a/manual/rockbox_interface/main.tex b/manual/rockbox_interface/main.tex
index ec76ce4ed5..33dae2f62f 100644
--- a/manual/rockbox_interface/main.tex
+++ b/manual/rockbox_interface/main.tex
@@ -827,10 +827,13 @@ properly.}
 
   \opt{usb_power}{
     \section{USB Charging}
-    To charge your \dap{} over USB, hold any button while plugging it
-    in. This will prevent it from connecting to your computer and let you
-    continue to use it normally. Your \dap{} must already be in Rockbox for this
-    to function.
+    Whenever your \dap{} is connected to USB, it will automatically charge.
+    However, depending on the \config{usb\_mode} setting, the \dap{} may also
+    enter mass storage mode or prompt the user for what action to take.
+    When the \dap{} is configured to enter mass storage mode or automatically
+    charge, you may trigger the opposite behaivor by holding down any button
+    while plugging it in.  Your \dap{} must already be in Rockbox for this to
+    function.
     \nopt{fuzeplus}{
     \note{Be aware that this button may still perform its normal function, so
     it is recommended to use a button without harmful side effects, such as