* @file usb_moded-udev.c

*

* Copyright (C) 2011 Nokia Corporation. All rights reserved.

* Copyright (C) 2013-2018 Jolla Ltd.

*

* @author: Philippe De Swert <philippe.de-swert@nokia.com>

* @author: Philippe De Swert <phdeswer@lumi.maa>

* @author: Tapio Rantala <ext-tapio.rantala@nokia.com>

* @author: Philippe De Swert <philippedeswert@gmail.com>

* @author: Philippe De Swert <philippe.deswert@jollamobile.com>

* @author: Jarko Poutiainen <jarko.poutiainen@jollamobile.com>

* @author: Simo Piiroinen <simo.piiroinen@jollamobile.com>

*

* 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

*/

#include <stdio.h>

#include <stdlib.h>

#include <locale.h>

#include <unistd.h>

#include <poll.h>

#include <libudev.h>

#include <glib.h>

#include "usb_moded-log.h"

#include "usb_moded-config-private.h"

#include "usb_moded-udev.h"

/* ========================================================================= *

* Types

* ========================================================================= */

typedef enum {

CABLE_STATE_UNKNOWN,

CABLE_STATE_DISCONNECTED,

CABLE_STATE_CHARGER_CONNECTED,

CABLE_STATE_PC_CONNECTED,

CABLE_STATE_NUMOF

} cable_state_t;

/* ========================================================================= *

* Prototypes

* ========================================================================= */

/* -- cable -- */

static gboolean cable_state_timer_cb (gpointer aptr);

static void cable_state_stop_timer (void);

static void cable_state_start_timer(void);

static bool cable_state_connected (void);

static cable_state_t cable_state_get (void);

static void cable_state_set (cable_state_t state);

static void cable_state_changed (void);

static void cable_state_from_udev (cable_state_t state);

/* -- umudev -- */

static void umudev_io_error_cb (gpointer data);

static gboolean umudev_io_input_cb (GIOChannel *iochannel, GIOCondition cond, gpointer data);

static void umudev_parse_properties (struct udev_device *dev, bool initial);

static int umudev_score_as_power_supply(const char *syspath);

gboolean umudev_init (void);

void umudev_quit (void);

/* ========================================================================= *

* Data

* ========================================================================= */

static const char * const cable_state_name[CABLE_STATE_NUMOF] = {

[CABLE_STATE_UNKNOWN] = "unknown",

[CABLE_STATE_DISCONNECTED] = "disconnected",

[CABLE_STATE_CHARGER_CONNECTED] = "charger_connected",

[CABLE_STATE_PC_CONNECTED] = "pc_connected",

};

static struct udev *umudev_object = 0;

static struct udev_monitor *umudev_monitor = 0;

static gchar *umudev_sysname = 0;

static guint umudev_watch_id = 0;

static bool umudev_in_cleanup = false;

/** Cable state as evaluated from udev events */

static cable_state_t cable_state_current = CABLE_STATE_UNKNOWN;

/** Cable state considered active by usb-moded */

static cable_state_t cable_state_active = CABLE_STATE_UNKNOWN;

/** Previously active cable state */

static cable_state_t cable_state_previous = CABLE_STATE_UNKNOWN;

/** Timer id for delaying: reported by udev -> active in usb-moded */

static guint cable_state_timer_id = 0;

/* ========================================================================= *

* cable state

* ========================================================================= */

(void)aptr;

cable_state_timer_id = 0;

log_debug("trigger delayed transfer to: %s",

cable_state_name[cable_state_current]);

cable_state_set(cable_state_current);

}

static void cable_state_stop_timer(void)

{

if( cable_state_timer_id ) {

log_debug("cancel delayed transfer to: %s",

cable_state_name[cable_state_current]);

g_source_remove(cable_state_timer_id),

cable_state_timer_id = 0;

}

static void cable_state_start_timer(void)

{

if( !cable_state_timer_id ) {

log_debug("schedule delayed transfer to: %s",

cable_state_name[cable_state_current]);

cable_state_timer_id = g_timeout_add(usbmoded_cable_connection_delay,

cable_state_timer_cb, 0);

}

static bool

cable_state_connected(void)

{

bool connected = false;

switch( cable_state_get() ) {

default:

break;

case CABLE_STATE_CHARGER_CONNECTED:

case CABLE_STATE_PC_CONNECTED:

connected = true;

break;

return cable_state_active;

}

static void cable_state_set(cable_state_t state)

{

cable_state_stop_timer();

if( cable_state_active == state )

goto EXIT;

cable_state_previous = cable_state_active;

cable_state_active = state;

log_debug("cable_state: %s -> %s",

cable_state_name[cable_state_previous],

cable_state_name[cable_state_active]);

cable_state_changed();

EXIT:

return;

}

static void cable_state_changed(void)

{

/* The rest of usb-moded separates charger

* and pc connection states... make single

* state tracking compatible with that. */

/* First handle pc/charger disconnect based

* on previous state.

*/

switch( cable_state_previous ) {

default:

case CABLE_STATE_DISCONNECTED:

/* dontcare */

break;

case CABLE_STATE_CHARGER_CONNECTED:

log_debug("*** HANDLE CHARGER DISCONNECT");

usbmoded_set_charger_connected(false);

break;

case CABLE_STATE_PC_CONNECTED:

log_debug("*** HANDLE PC DISCONNECT");

usbmoded_set_usb_connected(false);

break;

/* Then handle pc/charger sconnect based

* on current state.

*/

switch( cable_state_active ) {

default:

case CABLE_STATE_DISCONNECTED:

/* dontcare */

break;

case CABLE_STATE_CHARGER_CONNECTED:

log_debug("*** HANDLE CHARGER CONNECT");

usbmoded_set_charger_connected(true);

break;

case CABLE_STATE_PC_CONNECTED:

log_debug("*** HANDLE PC CONNECT");

usbmoded_set_usb_connected(true);

break;

}

static void cable_state_from_udev(cable_state_t curr)

{

cable_state_t prev = cable_state_current;

cable_state_current = curr;

if( prev == curr )

goto EXIT;

log_debug("reported cable state: %s -> %s",

cable_state_name[prev],

cable_state_name[curr]);

if( curr == CABLE_STATE_PC_CONNECTED && prev != CABLE_STATE_UNKNOWN )

cable_state_start_timer();

else

cable_state_set(curr);

EXIT:

return;

}

/* ========================================================================= *

* legacy code

* ========================================================================= */

static void umudev_io_error_cb(gpointer data)

(void)data;

/* we do not want to restart when we try to clean up */

if( !umudev_in_cleanup ) {

log_debug("USB connection watch destroyed, restarting it\n!");

/* restart trigger */

umudev_quit();

umudev_init();

}

}

(void)iochannel;

(void)data;

gboolean continue_watching = TRUE;

/* No code paths are allowed to bypass the usbmoded_release_wakelock() call below */

usbmoded_acquire_wakelock(USB_MODED_WAKELOCK_PROCESS_INPUT);

if( cond & G_IO_IN )

{

/* This normally blocks but G_IO_IN indicates that we can read */

struct udev_device *dev = udev_monitor_receive_device(umudev_monitor);

if( !dev )

{

/* if we get something else something bad happened stop watching to avoid busylooping */

continue_watching = FALSE;

}

else

{

/* check if it is the actual device we want to check */

if( !strcmp(umudev_sysname, udev_device_get_sysname(dev)) )

{

if( !strcmp(udev_device_get_action(dev), "change") )

{

umudev_parse_properties(dev, false);

}

}

udev_device_unref(dev);

}

}

if( cond & (G_IO_ERR | G_IO_HUP | G_IO_NVAL) )

{

/* Unhandled errors turn io watch to virtual busyloop too */

continue_watching = FALSE;

}

if( !continue_watching && umudev_watch_id )

{

umudev_watch_id = 0;

log_crit("udev io watch disabled");

}

}

(void)initial;

/* udev properties we are interested in */

const char *power_supply_present = 0;

const char *power_supply_online = 0;

const char *power_supply_type = 0;

/* Assume there is no usb connection until proven otherwise */

bool connected = false;

/* Unless debug logging has been request via command line,

* suppress warnings about potential property issues and/or

* fallback strategies applied (to avoid spamming due to the

* code below seeing the same property values over and over

* again also in stable states).

*/

bool warnings = log_p(LOG_DEBUG);

/*

* Check for present first as some drivers use online for when charging

* is enabled

*/

power_supply_present = udev_device_get_property_value(dev, "POWER_SUPPLY_PRESENT");

if( !power_supply_present ) {

power_supply_present =

power_supply_online = udev_device_get_property_value(dev, "POWER_SUPPLY_ONLINE");

}

if( power_supply_present && !strcmp(power_supply_present, "1") )

connected = true;

/* Transition period = Connection status derived from udev

* events disagrees with usb-moded side bookkeeping. */

if( connected != usbmoded_get_connection_state() ) {

/* Enable udev property diagnostic logging */

warnings = true;

/* Block suspend briefly */

usbmoded_delay_suspend();

}

if( !connected ) {

/* Handle: Disconnected */

if( warnings && !power_supply_present )

log_err("No usable power supply indicator\n");

cable_state_from_udev(CABLE_STATE_DISCONNECTED);

}

else {

if( warnings && power_supply_online )

log_warning("Using online property\n");

/* At least h4113 i.e. "Xperia XA2 - Dual SIM" seem to have

* POWER_SUPPLY_REAL_TYPE udev property with information

* that usb-moded expects to be in POWER_SUPPLY_TYPE prop.

*/

power_supply_type = udev_device_get_property_value(dev, "POWER_SUPPLY_REAL_TYPE");

if( !power_supply_type )

power_supply_type = udev_device_get_property_value(dev, "POWER_SUPPLY_TYPE");

/*

* Power supply type might not exist also :(

* Send connected event but this will not be able

* to discriminate between charger/cable.

*/

if( !power_supply_type ) {

if( warnings )

log_warning("Fallback since cable detection might not be accurate. "

"Will connect on any voltage on charger.\n");

cable_state_from_udev(CABLE_STATE_PC_CONNECTED);

goto cleanup;

}

log_debug("CONNECTED - POWER_SUPPLY_TYPE = %s", power_supply_type);

if( !strcmp(power_supply_type, "USB") ||

!strcmp(power_supply_type, "USB_CDP") ) {

cable_state_from_udev(CABLE_STATE_PC_CONNECTED);

}

else if( !strcmp(power_supply_type, "USB_DCP") ||

!strcmp(power_supply_type, "USB_HVDCP") ||

!strcmp(power_supply_type, "USB_HVDCP_3") ) {

cable_state_from_udev(CABLE_STATE_CHARGER_CONNECTED);

}

else if( !strcmp(power_supply_type, "USB_FLOAT")) {

if( !cable_state_connected() )

log_warning("connection type detection failed, assuming charger");

cable_state_from_udev(CABLE_STATE_CHARGER_CONNECTED);

}

else if( !strcmp(power_supply_type, "Unknown")) {

// nop

log_warning("unknown connection type reported, assuming disconnected");

cable_state_from_udev(CABLE_STATE_DISCONNECTED);

}

else {

if( warnings )

log_warning("unhandled power supply type: %s", power_supply_type);

cable_state_from_udev(CABLE_STATE_DISCONNECTED);

}

}

cleanup:

return;

}

int score = 0;

struct udev_device *dev = 0;

const char *sysname = 0;

if( !umudev_object )

goto EXIT;

if( !(dev = udev_device_new_from_syspath(umudev_object, syspath)) )

goto EXIT;

if( !(sysname = udev_device_get_sysname(dev)) )

goto EXIT;

/* try to assign a weighed score */

/* check that it is not a battery */

if(strstr(sysname, "battery") || strstr(sysname, "BAT"))

goto EXIT;

/* if it contains usb in the name it very likely is good */

if(strstr(sysname, "usb"))

score = score + 10;

/* often charger is also mentioned in the name */

if(strstr(sysname, "charger"))

score = score + 5;

/* present property is used to detect activity, however online is better */

if(udev_device_get_property_value(dev, "POWER_SUPPLY_PRESENT"))

score = score + 5;

if(udev_device_get_property_value(dev, "POWER_SUPPLY_ONLINE"))

score = score + 10;

/* type is used to detect if it is a cable or dedicated charger.

if(udev_device_get_property_value(dev, "POWER_SUPPLY_TYPE"))

score = score + 10;

EXIT:

/* clean up */

if( dev )

udev_device_unref(dev);

return score;

}

char *configured_device = NULL;

char *configured_subsystem = NULL;

struct udev_device *dev = 0;

static GIOChannel *iochannel = 0;

int ret = 0;

/* Clear in-cleanup in case of restart */

umudev_in_cleanup = false;

/* Create the udev object */

if( !(umudev_object = udev_new()) ) {

log_err("Can't create umudev_object\n");

goto EXIT;

}

if( !(configured_device = config_find_udev_path()) )

configured_device = g_strdup("/sys/class/power_supply/usb");

if( !(configured_subsystem = config_find_udev_subsystem()) )

configured_subsystem = g_strdup("power_supply");

/* Try with configured / default device */

dev = udev_device_new_from_syspath(umudev_object, configured_device);

/* If needed, try heuristics */

if( !dev ) {

log_debug("Trying to guess $power_supply device.\n");

int current_score = 0;

gchar *current_name = 0;

struct udev_enumerate *list;

struct udev_list_entry *list_entry;

struct udev_list_entry *first_entry;

list = udev_enumerate_new(umudev_object);

udev_enumerate_add_match_subsystem(list, "power_supply");

udev_enumerate_scan_devices(list);

first_entry = udev_enumerate_get_list_entry(list);

udev_list_entry_foreach(list_entry, first_entry) {

const char *name = udev_list_entry_get_name(list_entry);

int score = umudev_score_as_power_supply(name);

if( current_score < score ) {

g_free(current_name);

current_name = g_strdup(name);

current_score = score;

}

}

/* check if we found anything with some kind of score */

if(current_score > 0) {

dev = udev_device_new_from_syspath(umudev_object, current_name);

}

g_free(current_name);

}

/* Give up if no power supply device was found */

if( !dev ) {

log_err("Unable to find $power_supply device.");

/* communicate failure, mainloop will exit and call appropriate clean-up */

goto EXIT;

}

/* Cache device name */

umudev_sysname = g_strdup(udev_device_get_sysname(dev));

log_debug("device name = %s\n", umudev_sysname);

/* Start monitoring for changes */

umudev_monitor = udev_monitor_new_from_netlink(umudev_object, "udev");

if( !umudev_monitor )

{

log_err("Unable to monitor the netlink\n");

/* communicate failure, mainloop will exit and call appropriate clean-up */

goto EXIT;

}

ret = udev_monitor_filter_add_match_subsystem_devtype(umudev_monitor,

configured_subsystem,

NULL);

if(ret != 0)

{

log_err("Udev match failed.\n");

goto EXIT;

}

ret = udev_monitor_enable_receiving(umudev_monitor);

if(ret != 0)

{

log_err("Failed to enable monitor recieving.\n");

goto EXIT;

}

iochannel = g_io_channel_unix_new(udev_monitor_get_fd(umudev_monitor));

if( !iochannel )

goto EXIT;

umudev_watch_id = g_io_add_watch_full(iochannel, 0, G_IO_IN, umudev_io_input_cb, NULL, umudev_io_error_cb);

if( !umudev_watch_id )

goto EXIT;

/* everything went well */

success = TRUE;

/* check initial status */

umudev_parse_properties(dev, true);

EXIT:

/* Cleanup local resources */

if( iochannel )

g_io_channel_unref(iochannel);

if( dev )

udev_device_unref(dev);

g_free(configured_subsystem);

g_free(configured_device);

/* All or nothing */

if( !success )

umudev_quit();

return success;

}

log_debug("HWhal cleanup\n");

if( umudev_watch_id )

{

g_source_remove(umudev_watch_id),

umudev_watch_id = 0;

}

if( umudev_monitor ) {

udev_monitor_unref(umudev_monitor),

umudev_monitor = 0;

}

if( umudev_object ) {

udev_unref(umudev_object),

umudev_object =0 ;

}

g_free(umudev_sysname),

umudev_sysname = 0;

cable_state_stop_timer();