init: add charge mode handling

Introduces a 'charger' section that is processed when androidboot.mode
supplied on the kernel commandline is "charger".

In this mode, sections such as fs, post-fs, etc are skipped. Only the
'early-init' and 'init' sections of the init rc files are processed before
processing the 'charger' section.

Change-Id: If9eb6334de18f04cbcf2aab784578e2993615242
Signed-off-by: Dima Zavin <dima@android.com>

2 files changed, 18 insertions, 8 deletions

diff --git a/init/init.c b/init/init.c
index eab14f6..5058b17 100755
--- a/init/init.c
+++ b/init/init.c
@@ -744,20 +744,27 @@ int main(int argc, char **argv)
     queue_builtin_action(console_init_action, "console_init");
     queue_builtin_action(set_init_properties_action, "set_init_properties");
 
-        /* execute all the boot actions to get us started */
+    /* execute all the boot actions to get us started */
     action_for_each_trigger("init", action_add_queue_tail);
-    action_for_each_trigger("early-fs", action_add_queue_tail);
-    action_for_each_trigger("fs", action_add_queue_tail);
-    action_for_each_trigger("post-fs", action_add_queue_tail);
-    action_for_each_trigger("post-fs-data", action_add_queue_tail);
+
+    /* skip mounting filesystems in charger mode */
+    if (strcmp(bootmode, "charger") != 0) {
+        action_for_each_trigger("early-fs", action_add_queue_tail);
+        action_for_each_trigger("fs", action_add_queue_tail);
+        action_for_each_trigger("post-fs", action_add_queue_tail);
+        action_for_each_trigger("post-fs-data", action_add_queue_tail);
+    }
 
     queue_builtin_action(property_service_init_action, "property_service_init");
     queue_builtin_action(signal_init_action, "signal_init");
     queue_builtin_action(check_startup_action, "check_startup");
 
-    /* execute all the boot actions to get us started */
-    action_for_each_trigger("early-boot", action_add_queue_tail);
-    action_for_each_trigger("boot", action_add_queue_tail);
+    if (!strcmp(bootmode, "charger")) {
+        action_for_each_trigger("charger", action_add_queue_tail);
+    } else {
+        action_for_each_trigger("early-boot", action_add_queue_tail);
+        action_for_each_trigger("boot", action_add_queue_tail);
+    }
 
         /* run all property triggers based on current state of the properties */
     queue_builtin_action(queue_property_triggers_action, "queue_propety_triggers");
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 8d6bf97..a5a0bc0 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -263,6 +263,9 @@ on boot
 on nonencrypted
     class_start late_start
 
+on charger
+    class_start charger
+
 on property:vold.decrypt=trigger_reset_main
     class_reset main