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// SPDX-License-Identifier: GPL-2.0-only
/*
* The Industrial I/O core, software IIO devices functions
*
* Copyright (c) 2016 Intel Corporation
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/iio/sw_device.h>
#include <linux/iio/configfs.h>
#include <linux/configfs.h>
static struct config_group *iio_devices_group;
static const struct config_item_type iio_device_type_group_type;
static const struct config_item_type iio_devices_group_type = {
.ct_owner = THIS_MODULE,
};
static LIST_HEAD(iio_device_types_list);
static DEFINE_MUTEX(iio_device_types_lock);
static
struct iio_sw_device_type *__iio_find_sw_device_type(const char *name,
unsigned len)
{
struct iio_sw_device_type *d = NULL, *iter;
list_for_each_entry(iter, &iio_device_types_list, list)
if (!strcmp(iter->name, name)) {
d = iter;
break;
}
return d;
}
int iio_register_sw_device_type(struct iio_sw_device_type *d)
{
struct iio_sw_device_type *iter;
int ret = 0;
mutex_lock(&iio_device_types_lock);
iter = __iio_find_sw_device_type(d->name, strlen(d->name));
if (iter)
ret = -EBUSY;
else
list_add_tail(&d->list, &iio_device_types_list);
mutex_unlock(&iio_device_types_lock);
if (ret)
return ret;
d->group = configfs_register_default_group(iio_devices_group, d->name,
&iio_device_type_group_type);
if (IS_ERR(d->group))
ret = PTR_ERR(d->group);
return ret;
}
EXPORT_SYMBOL(iio_register_sw_device_type);
void iio_unregister_sw_device_type(struct iio_sw_device_type *dt)
{
struct iio_sw_device_type *iter;
mutex_lock(&iio_device_types_lock);
iter = __iio_find_sw_device_type(dt->name, strlen(dt->name));
if (iter)
list_del(&dt->list);
mutex_unlock(&iio_device_types_lock);
configfs_unregister_default_group(dt->group);
}
EXPORT_SYMBOL(iio_unregister_sw_device_type);
static
struct iio_sw_device_type *iio_get_sw_device_type(const char *name)
{
struct iio_sw_device_type *dt;
mutex_lock(&iio_device_types_lock);
dt = __iio_find_sw_device_type(name, strlen(name));
if (dt && !try_module_get(dt->owner))
dt = NULL;
mutex_unlock(&iio_device_types_lock);
return dt;
}
struct iio_sw_device *iio_sw_device_create(const char *type, const char *name)
{
struct iio_sw_device *d;
struct iio_sw_device_type *dt;
dt = iio_get_sw_device_type(type);
if (!dt) {
pr_err("Invalid device type: %s\n", type);
return ERR_PTR(-EINVAL);
}
d = dt->ops->probe(name);
if (IS_ERR(d))
goto out_module_put;
d->device_type = dt;
return d;
out_module_put:
module_put(dt->owner);
return d;
}
EXPORT_SYMBOL(iio_sw_device_create);
void iio_sw_device_destroy(struct iio_sw_device *d)
{
struct iio_sw_device_type *dt = d->device_type;
dt->ops->remove(d);
module_put(dt->owner);
}
EXPORT_SYMBOL(iio_sw_device_destroy);
static struct config_group *device_make_group(struct config_group *group,
const char *name)
{
struct iio_sw_device *d;
d = iio_sw_device_create(group->cg_item.ci_name, name);
if (IS_ERR(d))
return ERR_CAST(d);
config_item_set_name(&d->group.cg_item, "%s", name);
return &d->group;
}
static void device_drop_group(struct config_group *group,
struct config_item *item)
{
struct iio_sw_device *d = to_iio_sw_device(item);
iio_sw_device_destroy(d);
config_item_put(item);
}
static struct configfs_group_operations device_ops = {
.make_group = &device_make_group,
.drop_item = &device_drop_group,
};
static const struct config_item_type iio_device_type_group_type = {
.ct_group_ops = &device_ops,
.ct_owner = THIS_MODULE,
};
static int __init iio_sw_device_init(void)
{
iio_devices_group =
configfs_register_default_group(&iio_configfs_subsys.su_group,
"devices",
&iio_devices_group_type);
return PTR_ERR_OR_ZERO(iio_devices_group);
}
module_init(iio_sw_device_init);
static void __exit iio_sw_device_exit(void)
{
configfs_unregister_default_group(iio_devices_group);
}
module_exit(iio_sw_device_exit);
MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
MODULE_DESCRIPTION("Industrial I/O software devices support");
MODULE_LICENSE("GPL v2");
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