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usb_moded.c
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/**
@file usb_moded.c
Copyright (C) 2010 Nokia Corporation. All rights reserved.
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Copyright (C) 2012 Jolla. All rights reserved.
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@author: Philippe De Swert <philippe.de-swert@nokia.com>
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@author: Philippe De Swert <philippe.deswert@jollamobile.com>
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This program is free software; you can redistribute it and/or
modify it under the terms of the Lesser GNU General Public License
version 2 as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the Lesser GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
02110-1301 USA
*/
#define _GNU_SOURCE
#include <getopt.h>
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#include <stdio.h>
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#include <sys/stat.h>
#include <sys/wait.h>
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#include <signal.h>
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#include <libkmod.h>
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#ifdef SYSTEMD
#include <systemd/sd-daemon.h>
#endif
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#include "usb_moded.h"
#include "usb_moded-modes.h"
#include "usb_moded-dbus.h"
#include "usb_moded-dbus-private.h"
#include "usb_moded-hw-ab.h"
#include "usb_moded-modules.h"
#include "usb_moded-log.h"
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#include "usb_moded-lock.h"
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#include "usb_moded-modesetting.h"
#include "usb_moded-modules.h"
#include "usb_moded-appsync.h"
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#include "usb_moded-trigger.h"
#include "usb_moded-config.h"
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#include "usb_moded-config-private.h"
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#include "usb_moded-network.h"
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#include "usb_moded-mac.h"
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#include "usb_moded-android.h"
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#ifdef MEEGOLOCK
#include "usb_moded-dsme.h"
#endif
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/* global definitions */
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GMainLoop *mainloop = NULL;
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extern const char *log_name;
extern int log_level;
extern int log_type;
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gboolean rescue_mode = FALSE;
gboolean diag_mode = FALSE;
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gboolean hw_fallback = FALSE;
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gboolean android_broken_usb = FALSE;
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gboolean android_ignore_udev_events = FALSE;
gboolean android_ignore_next_udev_disconnect_event = FALSE;
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#ifdef SYSTEMD
static gboolean systemd_notify = FALSE;
#endif
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/** Default allowed cable detection delay
*
* To comply with USB standards, the delay should be
* less than 2 seconds to ensure timely enumeration.
*
* Any value <= zero means no delay.
*/
#define CABLE_CONNECTION_DELAY_DEFAULT 0
/** Maximum allowed cable detection delay
*
* Must be shorter than initial probing delay expected by
* dsme (currently 5 seconds) to avoid reboot loops in
* act dead mode.
*
* And shorter than USB_MODED_SUSPEND_DELAY_DEFAULT_MS to
* allow the timer to trigger also in display off scenarios.
*/
#define CABLE_CONNECTION_DELAY_MAXIMUM 4000
/** Currently allowed cable detection delay
*/
int cable_connection_delay = CABLE_CONNECTION_DELAY_DEFAULT;
/** Helper for setting allowed cable detection delay
*
* Used for implementing --max-cable-delay=<ms> option.
*/
static void set_cable_connection_delay(int delay_ms)
{
if( delay_ms < CABLE_CONNECTION_DELAY_MAXIMUM )
cable_connection_delay = delay_ms;
else {
cable_connection_delay = CABLE_CONNECTION_DELAY_MAXIMUM;
log_warning("using maximum connection delay: %d ms",
cable_connection_delay);
}
}
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struct usb_mode current_mode;
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guint charging_timeout = 0;
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static GList *modelist;
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/* static helper functions */
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static gboolean set_disconnected(gpointer data);
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static gboolean set_disconnected_silent(gpointer data);
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static void usb_moded_init(void);
static gboolean charging_fallback(gpointer data);
static void usage(void);
/* ============= Implementation starts here =========================================== */
/** set the usb connection status
*
* @param connected The connection status, true for connected
*
*/
void set_usb_connected(gboolean connected)
{
if(connected)
{
/* do not go through the routine if already connected to avoid
spurious load/unloads due to faulty signalling
NOKIA: careful with devicelock
*/
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if(current_mode.connected == connected)
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return;
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if(charging_timeout)
{
g_source_remove(charging_timeout);
charging_timeout = 0;
}
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current_mode.connected = TRUE;
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/* signal usb connected */
log_debug("usb connected\n");
usb_moded_send_signal(USB_CONNECTED);
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set_usb_connected_state();
}
else
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{
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if(current_mode.connected == FALSE)
return;
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if(android_ignore_next_udev_disconnect_event) {
android_ignore_next_udev_disconnect_event = FALSE;
return;
}
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current_mode.connected = FALSE;
set_disconnected(NULL);
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/* Some android kernels check for an active gadget to enable charging and
* cable detection, meaning USB is completely dead unless we keep the gadget
* active
*/
if(current_mode.android_usb_broken)
set_android_charging_mode();
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if (android_ignore_udev_events) {
android_ignore_next_udev_disconnect_event = TRUE;
}
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}
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}
static gboolean set_disconnected(gpointer data)
{
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/* let usb settle */
sleep(1);
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/* only disconnect for real if we are actually still disconnected */
if(!get_usb_connection_state())
{
log_debug("usb disconnected\n");
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/* signal usb disconnected */
usb_moded_send_signal(USB_DISCONNECTED);
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/* unload modules and general cleanup if not charging */
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if(strcmp(get_usb_mode(), MODE_CHARGING) ||
strcmp(get_usb_mode(), MODE_CHARGING_FALLBACK))
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usb_moded_mode_cleanup(get_usb_module());
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/* Nothing else as we do not need to do anything for cleaning up charging mode */
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usb_moded_module_cleanup(get_usb_module());
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set_usb_mode(MODE_UNDEFINED);
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}
return FALSE;
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}
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/* set disconnected without sending signals. */
static gboolean set_disconnected_silent(gpointer data)
{
if(!get_usb_connection_state())
{
log_debug("Resetting connection data after HUP\n");
/* unload modules and general cleanup if not charging */
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if(strcmp(get_usb_mode(), MODE_CHARGING) ||
strcmp(get_usb_mode(), MODE_CHARGING_FALLBACK))
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usb_moded_mode_cleanup(get_usb_module());
/* Nothing else as we do not need to do anything for cleaning up charging mode */
usb_moded_module_cleanup(get_usb_module());
set_usb_mode(MODE_UNDEFINED);
}
return FALSE;
}
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/** set and track charger state
*
*/
void set_charger_connected(gboolean state)
{
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/* check if charger is already connected
to avoid spamming dbus */
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if(current_mode.connected == state)
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return;
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if(state)
{
usb_moded_send_signal(CHARGER_CONNECTED);
set_usb_mode(MODE_CHARGER);
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current_mode.connected = TRUE;
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}
else
{
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current_mode.connected = FALSE;
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usb_moded_send_signal(CHARGER_DISCONNECTED);
set_usb_mode(MODE_UNDEFINED);
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current_mode.connected = FALSE;
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}
}
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/** set the chosen usb state
*
*/
void set_usb_connected_state(void)
{
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char *mode_to_set;
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#ifdef MEEGOLOCK
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int export = 1; /* assume locked */
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#endif /* MEEGOLOCK */
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if(rescue_mode)
{
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log_debug("Entering rescue mode!\n");
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set_usb_mode(MODE_DEVELOPER);
return;
}
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else if(diag_mode)
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{
log_debug("Entering diagnostic mode!\n");
if(modelist)
{
GList *iter = modelist;
struct mode_list_elem *data = iter->data;
set_usb_mode(data->mode_name);
}
return;
}
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mode_to_set = get_mode_setting();
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#ifdef MEEGOLOCK
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/* check if we are allowed to export system contents 0 is unlocked */
export = usb_moded_get_export_permission();
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/* We check also if the device is in user state or not.
If not we do not export anything. We presume ACT_DEAD charging */
if(mode_to_set && !export && is_in_user_state())
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#else
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if(mode_to_set)
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#endif /* MEEGOLOCK */
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{
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/* This is safe to do here as the starting condition is
MODE_UNDEFINED, and having a devicelock being activated when
a mode is set will not interrupt it */
if(!strcmp(mode_to_set, current_mode.mode))
goto end;
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if(!strcmp(MODE_ASK, mode_to_set))
{
/* send signal, mode will be set when the dialog service calls
the set_mode method call.
*/
usb_moded_send_signal(USB_CONNECTED_DIALOG_SHOW);
/* fallback to charging mode after 3 seconds */
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if( charging_timeout )
g_source_remove(charging_timeout);
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charging_timeout = g_timeout_add_seconds(3, charging_fallback, NULL);
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/* in case there was nobody listening for the UI, they will know
that the UI is needed by requesting the current mode */
set_usb_mode(MODE_ASK);
}
else
set_usb_mode(mode_to_set);
}
else
{
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/* config is corrupted or we do not have a mode configured, fallback to charging
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We also fall back here in case the device is locked and we do not
export the system contents. Or if we are in acting dead mode.
*/
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set_usb_mode(MODE_CHARGING_FALLBACK);
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}
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end:
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free(mode_to_set);
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}
/** set the usb mode
*
* @param mode The requested USB mode
*
*/
void set_usb_mode(const char *mode)
{
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/* set return to 1 to be sure to error out if no matching mode is found either */
int ret=1, net=0;
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#ifdef MEEGOLOCK
/* Do a second check in case timer suspend causes a race issue */
int export = 1;
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#endif
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log_debug("Setting %s\n", mode);
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/* CHARGING AND FALLBACK CHARGING are always ok to set, so this can be done
before the optional second device lock check */
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if(!strcmp(mode, MODE_CHARGING) || !strcmp(mode, MODE_CHARGING_FALLBACK))
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{
check_module_state(MODULE_MASS_STORAGE);
/* for charging we use a fake file_storage (blame USB certification for this insanity */
set_usb_module(MODULE_MASS_STORAGE);
/* MODULE_CHARGING has all the parameters defined, so it will not match the g_file_storage rule in usb_moded_load_module */
ret = usb_moded_load_module(MODULE_CHARGING);
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/* if charging mode setting did not succeed we might be dealing with android */
if(ret)
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{
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if (android_ignore_udev_events) {
android_ignore_next_udev_disconnect_event = TRUE;
}
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set_usb_module(MODULE_NONE);
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ret = set_android_charging_mode();
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}
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goto end;
}
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/* Dedicated charger mode needs nothing to be done and no user interaction */
if(!strcmp(mode, MODE_CHARGER))
{
ret = 0;
goto end;
}
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#ifdef MEEGOLOCK
/* check if we are allowed to export system contents 0 is unlocked */
/* In ACTDEAD export is always ok */
if(is_in_user_state())
{
export = usb_moded_get_export_permission();
if(export && !rescue_mode)
{
log_debug("Secondary device lock check failed. Not setting mode!\n");
goto end;
}
}
#endif /* MEEGOLOCK */
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/* nothing needs to be done for this mode but signalling.
Handled here to avoid issues with ask menu and devicelock */
if(!strcmp(mode, MODE_ASK))
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{
ret = 0;
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goto end;
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}
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/* go through all the dynamic modes if the modelist exists*/
if(modelist)
{
GList *iter;
for( iter = modelist; iter; iter = g_list_next(iter) )
{
struct mode_list_elem *data = iter->data;
if(!strcmp(mode, data->mode_name))
{
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log_debug("Matching mode %s found.\n", mode);
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check_module_state(data->mode_module);
set_usb_module(data->mode_module);
ret = usb_moded_load_module(data->mode_module);
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/* set data before calling any of the dynamic mode functions
as they will use the get_usb_mode_data function */
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set_usb_mode_data(data);
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/* check if modules are ok before continuing */
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if(!ret) {
if (android_ignore_udev_events) {
android_ignore_next_udev_disconnect_event = TRUE;
}
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ret = set_dynamic_mode();
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}
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}
}
}
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end:
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/* if ret != 0 then usb_module loading failed
no mode matched or MODE_UNDEFINED was requested */
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if(ret)
{
set_usb_module(MODULE_NONE);
mode = MODE_UNDEFINED;
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set_usb_mode_data(NULL);
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log_debug("mode setting failed or device disconnected, mode to set was = %s\n", mode);
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}
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if(net)
log_debug("Network setting failed!\n");
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free(current_mode.mode);
current_mode.mode = strdup(mode);
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/* CHARGING_FALLBACK is an internal mode not to be broadcasted outside */
if(!strcmp(mode, MODE_CHARGING_FALLBACK))
usb_moded_send_signal(MODE_CHARGING);
else
usb_moded_send_signal(get_usb_mode());
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}
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/** check if a given usb_mode exists
*
* @param mode The mode to look for
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* @return 0 if mode exists, 1 if it does not exist
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*
*/
int valid_mode(const char *mode)
{
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/* MODE_ASK, MODE_CHARGER and MODE_CHARGING_FALLBACK are not modes that are settable seen their special 'internal' status
so we only check the modes that are announed outside. Only exception is the built in MODE_CHARGING */
if(!strcmp(MODE_CHARGING, mode))
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return(0);
else
{
/* check dynamic modes */
if(modelist)
{
GList *iter;
for( iter = modelist; iter; iter = g_list_next(iter) )
{
struct mode_list_elem *data = iter->data;
if(!strcmp(mode, data->mode_name))
return(0);
}
}
}
return(1);
}
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/** make a list of all available usb modes
*
* @return a comma-separated list of modes (MODE_ASK not included as it is not a real mode)
*
*/
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gchar *get_mode_list(void)
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{
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GString *modelist_str;
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char *hidden_modes_list;
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gchar **hidden_mode_split = NULL;
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int hiddenmode = 0, i;
hidden_modes_list = get_hidden_modes();
if(hidden_modes_list)
{
hidden_mode_split = g_strsplit(hidden_modes_list, ",", 0);
}
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modelist_str = g_string_new(NULL);
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if(!diag_mode)
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{
/* check dynamic modes */
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if(modelist)
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{
GList *iter;
for( iter = modelist; iter; iter = g_list_next(iter) )
{
struct mode_list_elem *data = iter->data;
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if(hidden_modes_list && hidden_mode_split)
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for(i = 0; hidden_mode_split[i] != NULL; i++)
{
if(!strcmp(hidden_mode_split[i], data->mode_name))
hiddenmode = 1;
}
if(hiddenmode)
{
hiddenmode = 0;
continue;
}
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modelist_str = g_string_append(modelist_str, data->mode_name);
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modelist_str = g_string_append(modelist_str, ", ");
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}
}
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if(hidden_mode_split)
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g_strfreev(hidden_mode_split);
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/* end with charging mode */
g_string_append(modelist_str, MODE_CHARGING);
return(g_string_free(modelist_str, FALSE));
}
else
{
/* diag mode. there is only one active mode */
g_string_append(modelist_str, MODE_DIAG);
return(g_string_free(modelist_str, FALSE));
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}
}
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/** get the usb mode
*
* @return the currently set mode
*
*/
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inline const char * get_usb_mode(void)
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{
return(current_mode.mode);
}
/** set the loaded module
*
* @param module The module name for the requested mode
*
*/
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void set_usb_module(const char *module)
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{
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free(current_mode.module);
current_mode.module = strdup(module);
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}
/** get the supposedly loaded module
*
* @return The name of the loaded module
*
*/
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inline const char * get_usb_module(void)
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{
return(current_mode.module);
}
/** get if the cable is connected or not
*
* @ return A boolean value for connected (TRUE) or not (FALSE)
*
*/
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inline gboolean get_usb_connection_state(void)
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{
return current_mode.connected;
}
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/** set connection status for some corner cases
*
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* @param state The connection status that needs to be set. Connected (TRUE)
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*
*/
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inline void set_usb_connection_state(gboolean state)
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{
current_mode.connected = state;
}
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/** set the mode_list_elem data
*
* @param data mode_list_element pointer
*
*/
void set_usb_mode_data(struct mode_list_elem *data)
{
current_mode.data = data;
}
/** get the usb mode data
*
* @return a pointer to the usb mode data
*
*/
inline struct mode_list_elem * get_usb_mode_data(void)
{
return(current_mode.data);
}
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/*================ Static functions ===================================== */
/* set default values for usb_moded */
static void usb_moded_init(void)
{
current_mode.connected = FALSE;
current_mode.mounted = FALSE;
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current_mode.mode = strdup(MODE_UNDEFINED);
current_mode.module = strdup(MODULE_NONE);
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if(android_broken_usb)
current_mode.android_usb_broken = TRUE;
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/* check config, merge or create if outdated */
if(conf_file_merge() != 0)
{
log_err("Cannot create or find a valid configuration. Exiting.\n");
exit(1);
}
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#ifdef APP_SYNC
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readlist(diag_mode);
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/* make sure all services are down when starting */
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appsync_stop(1);
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modelist = read_mode_list(diag_mode);
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#endif /* APP_SYNC */
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if(check_trigger())
trigger_init();
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/* Set-up mac address before kmod */
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if(access("/etc/modprobe.d/g_ether.conf", F_OK) != 0)
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{
generate_random_mac();
}
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/* kmod init */
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usb_moded_module_ctx_init();
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/* Android specific stuff */
if(android_settings())
android_init_values();
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/* TODO: add more start-up clean-up and init here if needed */
}
/* charging fallback handler */
static gboolean charging_fallback(gpointer data)
{
/* if a mode has been set we don't want it changed to charging
* after 5 seconds. We set it to ask, so anything different
* means a mode has been set */
if(strcmp(get_usb_mode(), MODE_ASK) != 0)
return FALSE;
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set_usb_mode(MODE_CHARGING_FALLBACK);
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/* since this is the fallback, we keep an indication
for the UI, as we are not really in charging mode.
*/
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free(current_mode.mode);
current_mode.mode = strdup(MODE_ASK);
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current_mode.data = NULL;
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charging_timeout = 0;
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log_info("Falling back on charging mode.\n");
return(FALSE);
}
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static void handle_exit(void)
{
/* exiting and clean-up when mainloop ended */
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appsync_stop(1);
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hwal_cleanup();
usb_moded_dbus_cleanup();
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#ifdef MEEGOLOCK
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stop_devicelock_listener();
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#endif /* MEEGOLOCK */
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free_mode_list(modelist);
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usb_moded_module_ctx_cleanup();
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#ifdef APP_SYNC
free_appsync_list();
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#ifdef APP_SYNC_DBUS
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usb_moded_appsync_cleanup();
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#endif /* APP_SYNC_DBUS */
#endif /* APP_SYNC */
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/* dbus_shutdown(); This causes exit(1) and don't seem
to behave as documented */
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/* If the mainloop is initialised, unreference it */
if (mainloop != NULL)
{
g_main_loop_quit(mainloop);
g_main_loop_unref(mainloop);
}
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699
free(current_mode.mode);
free(current_mode.module);
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702
log_debug("All resources freed. Exiting!\n");
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707
exit(0);
}
static void sigint_handler(int signum)
{
708
709
struct mode_list_elem *data;
710
if(signum == SIGINT || signum == SIGTERM)
711
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713
handle_exit();
if(signum == SIGHUP)
{
714
715
/* clean up current mode */
data = get_usb_mode_data();
716
set_disconnected_silent(data);
717
/* clear existing data to be sure */
718
set_usb_mode_data(NULL);
719
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/* free and read in modelist again */
free_mode_list(modelist);
721
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modelist = read_mode_list(diag_mode);
723
724
send_supported_modes_signal();
725
}
726
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}
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734
/* Display usage information */
static void usage(void)
{
fprintf(stdout,
"Usage: usb_moded [OPTION]...\n"
"USB mode daemon\n"
"\n"
735
" -a, --android_usb_broken \tkeep gadget active on broken android kernels\n"
736
" -i, --android_usb_broken_udev_events \tignore incorrect disconnect events after mode setting\n"
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743
" -f, --fallback \tassume always connected\n"
" -s, --force-syslog \t\tlog to syslog\n"
" -T, --force-stderr \t\tlog to stderr\n"
" -D, --debug \t\tturn on debug printing\n"
" -d, --diag \t\tturn on diag mode\n"
" -h, --help \t\tdisplay this help and exit\n"
" -r, --rescue \t\trescue mode\n"
744
#ifdef SYSTEMD
745
" -n, --systemd \t\tnotify systemd when started up\n"
746
#endif
747
" -v, --version \t\toutput version information and exit\n"
748
" -m, --max-cable-delay=<ms>\tmaximum delay before accepting cable connection\n"
749
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751
"\n");
}
752
void send_supported_modes_signal(void)
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{
/* Send supported modes signal */
gchar *mode_list = get_mode_list();
usb_moded_send_supported_modes_signal(mode_list);
g_free(mode_list);
}
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762
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766
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768
769
void send_hidden_modes_signal(void)
{
/* Send hidden modes signal */
gchar *mode_list = get_hidden_modes();
if(mode_list) {
usb_moded_send_hidden_modes_signal(mode_list);
g_free(mode_list);
}
}
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922
923
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926
/** Pipe fd for transferring signals to mainloop context */
static int sigpipe_fd = -1;
/** Glib io watch callback for reading signals from signal pipe
*
* @param channel glib io channel
* @param condition wakeup reason
* @param data user data (unused)
*
* @return TRUE to keep the iowatch, or FALSE to disable it
*/
static gboolean sigpipe_read_signal_cb(GIOChannel *channel,
GIOCondition condition,
gpointer data)
{
gboolean keep_watch = FALSE;
int fd, rc, sig;
(void)data;
/* Should never happen, but we must disable the io watch
* if the pipe fd still goes into unexpected state ... */
if( condition & (G_IO_ERR | G_IO_HUP | G_IO_NVAL) )
goto EXIT;
if( (fd = g_io_channel_unix_get_fd(channel)) == -1 )
goto EXIT;
/* If the actual read fails, terminate with core dump */
rc = TEMP_FAILURE_RETRY(read(fd, &sig, sizeof sig));
if( rc != (int)sizeof sig )
abort();
/* handle the signal */
log_warning("handle signal: %s\n", strsignal(sig));
sigint_handler(sig);
keep_watch = TRUE;
EXIT:
if( !keep_watch )
log_crit("disabled signal handler io watch\n");
return keep_watch;
}
/** Async signal handler for writing signals to signal pipe
*
* @param sig the signal number to pass to mainloop via pipe
*/
static void sigpipe_write_signal_cb(int sig)
{
/* NOTE: This function *MUST* be kept async-signal-safe! */
static volatile int exit_tries = 0;
int rc;
/* Restore signal handler */
signal(sig, sigpipe_write_signal_cb);
switch( sig )
{
case SIGINT:
case SIGQUIT:
case SIGTERM:
/* If we receive multiple signals that should have
* caused the process to exit, assume that mainloop
* is stuck and terminate with core dump. */
if( ++exit_tries >= 2 )
abort();
break;
default:
break;
}
/* Transfer the signal to mainloop via pipe ... */
rc = TEMP_FAILURE_RETRY(write(sigpipe_fd, &sig, sizeof sig));
/* ... or terminate with core dump in case of failures */
if( rc != (int)sizeof sig )
abort();
}
/** Create a pipe and io watch for handling signal from glib mainloop
*
* @return TRUE on success, or FALSE in case of errors
*/
static gboolean sigpipe_crate_pipe(void)
{
gboolean res = FALSE;
GIOChannel *chn = 0;
int pfd[2] = { -1, -1 };
if( pipe2(pfd, O_CLOEXEC) == -1 )
goto EXIT;
if( (chn = g_io_channel_unix_new(pfd[0])) == 0 )
goto EXIT;
if( !g_io_add_watch(chn, G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL,
sigpipe_read_signal_cb, 0) )
goto EXIT;
g_io_channel_set_close_on_unref(chn, TRUE), pfd[0] = -1;
sigpipe_fd = pfd[1], pfd[1] = -1;
res = TRUE;
EXIT:
if( chn ) g_io_channel_unref(chn);
if( pfd[0] != -1 ) close(pfd[0]);
if( pfd[1] != -1 ) close(pfd[1]);
return res;
}
/** Install async signal handlers
*/
static void sigpipe_trap_signals(void)
{
static const int sig[] =
{
SIGINT,
SIGQUIT,
SIGTERM,
SIGHUP,
-1
};
for( size_t i = 0; sig[i] != -1; ++i )
{
signal(sig[i], sigpipe_write_signal_cb);
}
}
/** Initialize signal trapping
*
* @return TRUE on success, or FALSE in case of errors
*/
static gboolean sigpipe_init(void)
{
gboolean success = FALSE;
if( !sigpipe_crate_pipe() )
goto EXIT;
sigpipe_trap_signals();
success = TRUE;
EXIT:
return success;
}
927
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941
942
/** Write string to already existing sysfs file
*
* Note: Attempts to write to nonexisting files are silently ignored.
*
* @param path Where to write
* @param text What to write
*/
static void write_to_sysfs_file(const char *path, const char *text)
{
int fd = -1;
if (!path || !text)
goto EXIT;
if ((fd = open(path, O_WRONLY)) == -1) {
if (errno != ENOENT) {
943
log_warning("%s: open for writing failed: %m", path);
944
945
946
947
948
}
goto EXIT;
}
if (write(fd, text, strlen(text)) == -1) {
949
log_warning("%s: write failed : %m", path);
950
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985
986
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992
993
994
995
996
997
998
999
1000
goto EXIT;
}
EXIT:
if (fd != -1)
close(fd);
}
/** Acquire wakelock via sysfs
*
* Wakelock must be released via release_wakelock().
*
* Automatically terminating wakelock is used, so that we
* do not block suspend indefinately in case usb_moded
* gets stuck or crashes.
*
* Note: The name should be unique within the system.
*
* @param wakelock_name Wake lock to be acquired
*/
void acquire_wakelock(const char *wakelock_name)
{
char buff[256];
snprintf(buff, sizeof buff, "%s %lld",
wakelock_name,
USB_MODED_SUSPEND_DELAY_MAXIMUM_MS * 1000000LL);
write_to_sysfs_file("/sys/power/wake_lock", buff);
log_debug("acquire_wakelock %s", wakelock_name);
}
/** Release wakelock via sysfs
*
* @param wakelock_name Wake lock to be released
*/
void release_wakelock(const char *wakelock_name)
{
log_debug("release_wakelock %s", wakelock_name);
write_to_sysfs_file("/sys/power/wake_unlock", wakelock_name);
}
/** Flag for: USB_MODED_WAKELOCK_STATE_CHANGE has been acquired */
static bool blocking_suspend = false;
/** Timer for releasing USB_MODED_WAKELOCK_STATE_CHANGE */
static guint allow_suspend_id = 0;
/** Release wakelock acquired via delay_suspend()
*
* Meant to be called on usb-moded exit so that wakelocks
* are not left behind.