Add ability to boot from charger mode.

Add the ability to boot up directly from charger mode, instead of forcing
charger mode to initiate a full restart to launch 'full' android. This
should shave a few seconds off of boot time on supported devices (just
manta for now).

Change-Id: Ieec4494d929e92806e039f834d78b9002afd15c4

charger/charger.c

@@ -40,6 +40,7 @@
 #include <cutils/list.h>
 #include <cutils/misc.h>
 #include <cutils/uevent.h>
+#include <cutils/properties.h>
 
 #ifdef CHARGER_ENABLE_SUSPEND
 #include <suspend/autosuspend.h>
@@ -830,8 +831,16 @@ static void process_key(struct charger *charger, int code, int64_t now)
         if (key->down) {
             int64_t reboot_timeout = key->timestamp + POWER_ON_KEY_TIME;
             if (now >= reboot_timeout) {
-                LOGI("[%lld] rebooting\n", now);
-                android_reboot(ANDROID_RB_RESTART, 0, 0);
+                /* We do not currently support booting from charger mode on
+                   all devices. Check the property and continue booting or reboot
+                   accordingly. */
+                if (property_get_bool("ro.enable_boot_charger_mode", false)) {
+                    LOGI("[%lld] booting from charger mode\n", now);
+                    property_set("sys.boot_from_charger_mode", "1");
+                } else {
+                    LOGI("[%lld] rebooting\n", now);
+                    android_reboot(ANDROID_RB_RESTART, 0, 0);
+                }
             } else {
                 /* if the key is pressed but timeout hasn't expired,
                  * make sure we wake up at the right-ish time to check

init/builtins.c

@@ -877,6 +877,14 @@ int do_load_persist_props(int nargs, char **args) {
     return -1;
 }
 
+int do_load_all_props(int nargs, char **args) {
+    if (nargs == 1) {
+        load_all_props();
+        return 0;
+    }
+    return -1;
+}
+
 int do_wait(int nargs, char **args)
 {
     if (nargs == 2) {

init/init.c

@@ -1051,8 +1051,7 @@ int main(int argc, char **argv)
     is_charger = !strcmp(bootmode, "charger");
 
     INFO("property init\n");
-    if (!is_charger)
-        property_load_boot_defaults();
+    property_load_boot_defaults();
 
     INFO("reading config file\n");
     init_parse_config_file("/init.rc");
@@ -1067,28 +1066,19 @@ int main(int argc, char **argv)
     /* execute all the boot actions to get us started */
     action_for_each_trigger("init", action_add_queue_tail);
 
-    /* skip mounting filesystems in charger mode */
-    if (!is_charger) {
-        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);
-    }
-
     /* Repeat mix_hwrng_into_linux_rng in case /dev/hw_random or /dev/random
      * wasn't ready immediately after wait_for_coldboot_done
      */
     queue_builtin_action(mix_hwrng_into_linux_rng_action, "mix_hwrng_into_linux_rng");
-
     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");
 
+    /* Don't mount filesystems or start core system services if in charger mode. */
     if (is_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);
+        action_for_each_trigger("late-init", action_add_queue_tail);
     }
 
         /* run all property triggers based on current state of the properties */

init/init_parser.c

@@ -120,6 +120,7 @@ static int lookup_keyword(const char *s)
     case 'l':
         if (!strcmp(s, "oglevel")) return K_loglevel;
         if (!strcmp(s, "oad_persist_props")) return K_load_persist_props;
+        if (!strcmp(s, "oad_all_props")) return K_load_all_props;
         break;
     case 'm':
         if (!strcmp(s, "kdir")) return K_mkdir;

init/keywords.h

@@ -39,6 +39,7 @@ int do_chown(int nargs, char **args);
 int do_chmod(int nargs, char **args);
 int do_loglevel(int nargs, char **args);
 int do_load_persist_props(int nargs, char **args);
+int do_load_all_props(int nargs, char **args);
 int do_wait(int nargs, char **args);
 #define __MAKE_KEYWORD_ENUM__
 #define KEYWORD(symbol, flags, nargs, func) K_##symbol,
@@ -101,6 +102,7 @@ enum {
     KEYWORD(chmod,       COMMAND, 2, do_chmod)
     KEYWORD(loglevel,    COMMAND, 1, do_loglevel)
     KEYWORD(load_persist_props,    COMMAND, 0, do_load_persist_props)
+    KEYWORD(load_all_props,        COMMAND, 0, do_load_all_props)
     KEYWORD(ioprio,      OPTION,  0, 0)
 #ifdef __MAKE_KEYWORD_ENUM__
     KEYWORD_COUNT,

init/property_service.c

@@ -621,10 +621,8 @@ void load_persist_props(void)
     load_persistent_properties();
 }
 
-void start_property_service(void)
+void load_all_props(void)
 {
-    int fd;
-
     load_properties_from_file(PROP_PATH_SYSTEM_BUILD, NULL);
     load_properties_from_file(PROP_PATH_SYSTEM_DEFAULT, NULL);
     load_properties_from_file(PROP_PATH_FACTORY, "ro.*");
@@ -633,6 +631,11 @@ void start_property_service(void)
 
     /* Read persistent properties after all default values have been loaded. */
     load_persistent_properties();
+}
+
+void start_property_service(void)
+{
+    int fd;
 
     fd = create_socket(PROP_SERVICE_NAME, SOCK_STREAM, 0666, 0, 0, NULL);
     if(fd < 0) return;

init/property_service.h

@@ -24,6 +24,7 @@ extern void handle_property_set_fd(void);
 extern void property_init(void);
 extern void property_load_boot_defaults(void);
 extern void load_persist_props(void);
+extern void load_all_props(void);
 extern void start_property_service(void);
 void get_property_workspace(int *fd, int *sz);
 extern int __property_get(const char *name, char *value);

rootdir/init.rc

@@ -154,6 +154,31 @@ on init
     chown system log /sys/fs/pstore/console-ramoops
     chmod 0440 /sys/fs/pstore/console-ramoops
 
+# Healthd can trigger a full boot from charger mode by signaling this
+# property when the power button is held.
+on property:sys.boot_from_charger_mode=1
+    class_stop charger
+    trigger late-init
+
+# Load properties from /system/ + /factory after fs mount.
+on load_all_props_action
+    load_all_props
+
+# Mount filesystems and start core system services.
+on late-init
+    trigger early-fs
+    trigger fs
+    trigger post-fs
+    trigger post-fs-data
+
+    # Load properties from /system/ + /factory after fs mount. Place
+    # this in another action so that the load will be scheduled after the prior
+    # issued fs triggers have completed.
+    trigger load_all_props_action
+
+    trigger early-boot
+    trigger boot
+
 on post-fs
     # once everything is setup, no need to modify /
     mount rootfs rootfs / ro remount