/**
* bus_add_device - add device to bus
* @dev: device being added
*
* - Add device's bus attributes.
* - Create links to device's bus.
* - Add the device to its bus's list of devices.
*/
int bus_add_device(struct device *dev)
{
struct bus_type *bus = bus_get(dev->bus);
int error = 0;
if (bus) {
pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
error = device_add_attrs(bus, dev);
if (error)
goto out_put;
error = sysfs_create_link(&bus->p->devices_kset->kobj,
&dev->kobj, dev_name(dev));
if (error)
goto out_id;
error = sysfs_create_link(&dev->kobj,
&dev->bus->p->subsys.kobj, "subsystem");
if (error)
goto out_subsys;
klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
}
return 0;
out_subsys:
sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
out_id:
device_remove_attrs(bus, dev);
out_put:
bus_put(dev->bus);
return error;
}
static ssize_t driver_bind(struct device_driver *drv,
const char *buf, size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
if (dev->parent)
down(&dev->parent->sem);
down(&dev->sem);
err = driver_probe_device(drv, dev);
up(&dev->sem);
if (dev->parent)
up(&dev->parent->sem);
if (err > 0) {
err = count;
} else if (err == 0) {
err = -ENODEV;
}
}
put_device(dev);
bus_put(bus);
return err;
}
/*
* Manually attach a device to a driver.
* Note: the driver must want to bind to the device,
* it is not possible to override the driver's id table.
*/
static ssize_t driver_bind(struct device_driver *drv,
const char *buf, size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
if (dev->parent) /* Needed for USB */
device_lock(dev->parent);
device_lock(dev);
err = driver_probe_device(drv, dev);
device_unlock(dev);
if (dev->parent)
device_unlock(dev->parent);
if (err > 0) {
/* success */
err = count;
} else if (err == 0) {
/* driver didn't accept device */
err = -ENODEV;
}
}
put_device(dev);
bus_put(bus);
return err;
}
void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr)
{
if (bus_get(bus)) {
sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);
bus_put(bus);
}
}
//在sysfs中添加两个链接: 一个在总线目录下指向设备，另一个在设备的目录下指向总线子系统。
int bus_add_device(struct device * dev)
{
struct bus_type * bus = bus_get(dev->bus);
int error = 0;
if (bus) {
pr_debug("bus %s: add device %s\n", bus->name, dev->bus_id);
error = device_add_attrs(bus, dev);
if (error)
goto out_put;
error = sysfs_create_link(&bus->devices.kobj,
&dev->kobj, dev->bus_id);
if (error)
goto out_id;
error = sysfs_create_link(&dev->kobj,
&dev->bus->subsys.kobj, "subsystem");
if (error)
goto out_subsys;
error = make_deprecated_bus_links(dev);
if (error)
goto out_deprecated;
}
return 0;
out_deprecated:
sysfs_remove_link(&dev->kobj, "subsystem");
out_subsys:
sysfs_remove_link(&bus->devices.kobj, dev->bus_id);
out_id:
device_remove_attrs(bus, dev);
out_put:
bus_put(dev->bus);
return error;
}
/*
* Manually attach a device to a driver.
* Note: the driver must want to bind to the device,
* it is not possible to override the driver's id table.
*/
static ssize_t driver_bind(struct device_driver *drv, const char *buf, size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
if (dev && dev->driver == NULL)
{
if (dev->parent) /* Needed for USB */
down(&dev->parent->sem);
down(&dev->sem);
err = driver_probe_device(drv, dev);
up(&dev->sem);
if (dev->parent)
up(&dev->parent->sem);
if (err > 0) /* success */
err = count;
else if (err == 0) /* driver didn't accept device */
err = -ENODEV;
}
put_device(dev);
bus_put(bus);
return err;
}
int bus_create_file(struct bus_type *bus, struct bus_attribute *attr)
{
int error;
if (bus_get(bus)) {
error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);
bus_put(bus);
} else
error = -EINVAL;
return error;
}
static gboolean on_handle_activate_session_on_seat(
LoginKitManager *interface,
GDBusMethodInvocation *invocation,
const gchar *arg_session,
const gchar *arg_seat,
gpointer user_data)
{
GDBusConnection *bus;
GVariant *reply;
GError *error = NULL;
char *session;
gboolean ret = FALSE;
g_log(G_LOG_DOMAIN,
G_LOG_LEVEL_INFO,
"activating %s on %s",
arg_session,
arg_seat);
bus = bus_get();
if (NULL == bus)
goto end;
/* find the session with the passed ID */
session = get_session_by_id(bus, arg_session);
if (NULL == session)
goto end;
reply = g_dbus_connection_call_sync(bus,
"org.freedesktop.ConsoleKit",
arg_session,
"org.freedesktop.ConsoleKit.Session",
"Activate",
NULL,
NULL,
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
&error);
if (NULL == reply) {
if (NULL != error)
g_error_free(error);
goto end;
}
g_variant_unref(reply);
ret = TRUE;
end:
login_kit_manager_complete_activate_session_on_seat(interface, invocation);
return ret;
}
/**
* bus_add_driver - Add a driver to the bus.
* @drv: driver.
*
*/
int bus_add_driver(struct device_driver *drv)
{
struct bus_type * bus = bus_get(drv->bus);
int error = 0;
if (!bus)
return -EINVAL;
pr_debug("bus %s: add driver %s\n", bus->name, drv->name);
error = kobject_set_name(&drv->kobj, "%s", drv->name);
if (error)
goto out_put_bus;
drv->kobj.kset = &bus->drivers;
error = kobject_register(&drv->kobj);
if (error)
goto out_put_bus;
//如果总线支持自动探测，则调用driver_attach。
if (drv->bus->drivers_autoprobe)
{
error = driver_attach(drv);
if (error)
goto out_unregister;
}
//将该驱动程序添加到总线上注册的所有驱动程序的链表中
klist_add_tail(&drv->knode_bus, &bus->klist_drivers);
module_add_driver(drv->owner, drv);
error = driver_create_file(drv, &driver_attr_uevent);
if (error)
{
printk(KERN_ERR "%s: uevent attr (%s) failed\n", __FUNCTION__, drv->name);
}
error = driver_add_attrs(bus, drv);
if (error)
{
/* How the hell do we get out of this pickle? Give up */
printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n", __FUNCTION__, drv->name);
}
error = add_bind_files(drv);
if (error)
{
/* Ditto */
printk(KERN_ERR "%s: add_bind_files(%s) failed\n", __FUNCTION__, drv->name);
}
return error;
out_unregister:
kobject_unregister(&drv->kobj);
out_put_bus:
bus_put(bus);
return error;
}
/* Manually detach a device from its associated driver. */
static ssize_t unbind_store(struct device_driver *drv, const char *buf,
size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
if (dev && dev->driver == drv) {
device_driver_detach(dev);
err = count;
}
put_device(dev);
bus_put(bus);
return err;
}
static void signals_unsubscribe(void)
{
GDBusConnection *bus;
bus = bus_get();
if (NULL == bus)
return;
if (0 != g_added_signal) {
g_dbus_connection_signal_unsubscribe(bus, g_added_signal);
g_added_signal = 0;
}
if (0 != g_removed_signal) {
g_dbus_connection_signal_unsubscribe(bus, g_removed_signal);
g_removed_signal = 0;
}
}
/* Manually detach a device from its associated driver. */
static ssize_t driver_unbind(struct device_driver *drv,
const char *buf, size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
if (dev && dev->driver == drv) {
if (dev->parent) /* Needed for USB */
device_lock(dev->parent);
device_release_driver(dev);
if (dev->parent)
device_unlock(dev->parent);
err = count;
}
put_device(dev);
bus_put(bus);
return err;
}
static ssize_t driver_unbind(struct device_driver *drv,
const char *buf, size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
if (dev && dev->driver == drv) {
if (dev->parent) /* Needed for USB */
down(&dev->parent->sem);
device_release_driver(dev);
if (dev->parent)
up(&dev->parent->sem);
err = count;
}
put_device(dev);
bus_put(bus);
return err;
}
/**
* bus_add_device :设备dev和其所在的bus之间创建符号链接
* @dev:待加入设备
*/
int bus_add_device(struct device *dev)
{
struct bus_type *bus = bus_get(dev->bus);
int error = 0;
if (bus) {
pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
/*在dev->kobj目录下创建设备的属性文件，属性文件为bus的属性文件*/
error = device_add_attrs(bus, dev);
if (error)
goto out_put;
/*在dev所属bus的device目录下创建指向dev->kobj目录的符号链接，
*名字为dev_name(dev)*/
error = sysfs_create_link(&bus->p->devices_kset->kobj,
&dev->kobj, dev_name(dev));
if (error)
goto out_id;
/*在dev->kobj目录下创建指向其所在bus目录的符号链接，
* 符号名称为subsystem*/
error = sysfs_create_link(&dev->kobj,
&dev->bus->p->subsys.kobj, "subsystem");
if (error)
goto out_subsys;
error = make_deprecated_bus_links(dev);
if (error)
goto out_deprecated;
/*dev链入的bus的设备链表中*/
klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
}
return 0;
out_deprecated:
sysfs_remove_link(&dev->kobj, "subsystem");
out_subsys:
sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
out_id:
device_remove_attrs(bus, dev);
out_put:
bus_put(dev->bus);
return error;
}
/*
* Manually attach a device to a driver.
* Note: the driver must want to bind to the device,
* it is not possible to override the driver's id table.
*/
static ssize_t bind_store(struct device_driver *drv, const char *buf,
size_t count)
{
struct bus_type *bus = bus_get(drv->bus);
struct device *dev;
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
err = device_driver_attach(drv, dev);
if (err > 0) {
/* success */
err = count;
} else if (err == 0) {
/* driver didn't accept device */
err = -ENODEV;
}
}
put_device(dev);
bus_put(bus);
return err;
}
/**
* bus_add_driver - Add a driver to the bus.
* @drv: driver.
*/
int bus_add_driver(struct device_driver *drv)
{
struct bus_type *bus;
struct driver_private *priv;
int error = 0;
bus = bus_get(drv->bus);
if (!bus)
return -EINVAL;
pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv) {
error = -ENOMEM;
goto out_put_bus;
}
klist_init(&priv->klist_devices, NULL, NULL);
priv->driver = drv;
drv->p = priv;
priv->kobj.kset = bus->p->drivers_kset;
error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
"%s", drv->name);
if (error)
goto out_unregister;
if (drv->bus->p->drivers_autoprobe) {
error = driver_attach(drv);
if (error)
goto out_unregister;
}
klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
module_add_driver(drv->owner, drv);
error = driver_create_file(drv, &driver_attr_uevent);
if (error) {
printk(KERN_ERR "%s: uevent attr (%s) failed\n",
__func__, drv->name);
}
error = driver_add_attrs(bus, drv);
if (error) {
/* How the hell do we get out of this pickle? Give up */
printk(KERN_ERR "%s: driver_add_attrs(%s) failed\n",
__func__, drv->name);
}
if (!drv->suppress_bind_attrs) {
error = add_bind_files(drv);
if (error) {
/* Ditto */
printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
__func__, drv->name);
}
}
kobject_uevent(&priv->kobj, KOBJ_ADD);
return 0;
out_unregister:
kfree(drv->p);
drv->p = NULL;
kobject_put(&priv->kobj);
out_put_bus:
bus_put(bus);
return error;
}
/* the logind documentation says: "ListSeats() returns an array with all
* currently available seats. The structure in the array consists of the
* following fields: seat id, seat object path.". however, ConsoleKit's
* GetSeats method returns only the object path, so we have to call
* GetId for each seat */
static gboolean on_handle_list_seats(LoginKitManager *interface,
GDBusMethodInvocation *invocation,
gpointer user_data)
{
GVariantIter iter;
GVariant *reply;
GError *error = NULL;
GDBusConnection *bus;
GVariantBuilder *builder;
GVariant *ret;
GVariant *seats;
char *seat;
char *id;
g_log(G_LOG_DOMAIN, G_LOG_LEVEL_INFO, "listing available seats");
bus = bus_get();
if (NULL == bus)
return FALSE;
/* list all seats */
reply = g_dbus_connection_call_sync(bus,
"org.freedesktop.ConsoleKit",
"/org/freedesktop/ConsoleKit/Manager",
"org.freedesktop.ConsoleKit.Manager",
"GetSeats",
NULL,
G_VARIANT_TYPE("(ao)"),
G_DBUS_CALL_FLAGS_NONE,
-1,
NULL,
&error);
if (NULL == reply) {
if (NULL != error)
g_error_free(error);
return FALSE;
}
seats = g_variant_get_child_value(reply, 0);
g_variant_iter_init(&iter, seats);
/* create a builder object, to initialize an array */
builder = g_variant_builder_new(G_VARIANT_TYPE("a(so)"));
/* do a best-effort attempt to enumerate all seats */
while (TRUE == g_variant_iter_loop(&iter, "o", &seat, NULL)) {
id = get_seat_id(bus, seat);
if (NULL == id)
continue;
g_variant_builder_add(builder, "(so)", id, seat);
}
g_variant_unref(reply);
g_variant_unref(seats);
ret = g_variant_new("a(so)", builder);
g_variant_builder_unref(builder);
login_kit_manager_complete_list_seats(interface, invocation, ret);
return TRUE;
}
