Commit 0f3a8c3f authored by Daniel Baluta's avatar Daniel Baluta Committed by Jonathan Cameron
Browse files

iio: Add support for creating IIO devices via configfs



This is similar with support for creating triggers via configfs.
Devices will be hosted under:
	* /config/iio/devices

We allow users to register "device types" under:
	* /config/iio/devices/<device_types>/
Signed-off-by: default avatarDaniel Baluta <daniel.baluta@intel.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 0825cce2
......@@ -46,6 +46,14 @@ config IIO_CONSUMERS_PER_TRIGGER
This value controls the maximum number of consumers that a
given trigger may handle. Default is 2.
config IIO_SW_DEVICE
tristate "Enable software IIO device support"
select IIO_CONFIGFS
help
Provides IIO core support for software devices. A software
device can be created via configfs or directly by a driver
using the API provided.
config IIO_SW_TRIGGER
tristate "Enable software triggers support"
select IIO_CONFIGFS
......
......@@ -8,6 +8,7 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
obj-$(CONFIG_IIO_CONFIGFS) += industrialio-configfs.o
obj-$(CONFIG_IIO_SW_DEVICE) += industrialio-sw-device.o
obj-$(CONFIG_IIO_SW_TRIGGER) += industrialio-sw-trigger.o
obj-$(CONFIG_IIO_TRIGGERED_EVENT) += industrialio-triggered-event.o
......
/*
* The Industrial I/O core, software IIO devices functions
*
* Copyright (c) 2016 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#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 struct config_item_type iio_device_type_group_type;
static 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 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");
/*
* Industrial I/O software device interface
*
* Copyright (c) 2016 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#ifndef __IIO_SW_DEVICE
#define __IIO_SW_DEVICE
#include <linux/module.h>
#include <linux/device.h>
#include <linux/iio/iio.h>
#include <linux/configfs.h>
#define module_iio_sw_device_driver(__iio_sw_device_type) \
module_driver(__iio_sw_device_type, iio_register_sw_device_type, \
iio_unregister_sw_device_type)
struct iio_sw_device_ops;
struct iio_sw_device_type {
const char *name;
struct module *owner;
const struct iio_sw_device_ops *ops;
struct list_head list;
struct config_group *group;
};
struct iio_sw_device {
struct iio_dev *device;
struct iio_sw_device_type *device_type;
struct config_group group;
};
struct iio_sw_device_ops {
struct iio_sw_device* (*probe)(const char *);
int (*remove)(struct iio_sw_device *);
};
static inline
struct iio_sw_device *to_iio_sw_device(struct config_item *item)
{
return container_of(to_config_group(item), struct iio_sw_device,
group);
}
int iio_register_sw_device_type(struct iio_sw_device_type *dt);
void iio_unregister_sw_device_type(struct iio_sw_device_type *dt);
struct iio_sw_device *iio_sw_device_create(const char *, const char *);
void iio_sw_device_destroy(struct iio_sw_device *);
int iio_sw_device_type_configfs_register(struct iio_sw_device_type *dt);
void iio_sw_device_type_configfs_unregister(struct iio_sw_device_type *dt);
static inline
void iio_swd_group_init_type_name(struct iio_sw_device *d,
const char *name,
struct config_item_type *type)
{
#ifdef CONFIG_CONFIGFS_FS
config_group_init_type_name(&d->group, name, type);
#endif
}
#endif /* __IIO_SW_DEVICE */
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment