path: root/include/linux/device.h

// SPDX-License-Identifier: GPL-2.0
/*
 * device.h - generic, centralized driver model
 *
 * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org>
 * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de>
 * Copyright (c) 2008-2009 Novell Inc.
 *
 * See Documentation/driver-api/driver-model/ for more information.
 */

#ifndef _DEVICE_H_
#define _DEVICE_H_

#include <linux/dev_printk.h>
#include <linux/energy_model.h>
#include <linux/ioport.h>
#include <linux/kobject.h>
#include <linux/klist.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/atomic.h>
#include <linux/uidgid.h>
#include <linux/gfp.h>
#include <linux/overflow.h>
#include <linux/device/bus.h>
#include <linux/device/class.h>
#include <linux/device/driver.h>
#include <asm/device.h>

struct device;
struct device_private;
struct device_driver;
struct driver_private;
struct module;
struct class;
struct subsys_private;
struct device_node;
struct fwnode_handle;
struct iommu_ops;
struct iommu_group;
struct dev_pin_info;
struct dev_iommu;
struct msi_device_data;

/**
 * struct subsys_interface - interfaces to device functions
 * @name:       name of the device function
 * @subsys:     subsystem of the devices to attach to
 * @node:       the list of functions registered at the subsystem
 * @add_dev:    device hookup to device function handler
 * @remove_dev: device hookup to device function handler
 *
 * Simple interfaces attached to a subsystem. Multiple interfaces can
 * attach to a subsystem and its devices. Unlike drivers, they do not
 * exclusively claim or control devices. Interfaces usually represent
 * a specific functionality of a subsystem/class of devices.
 */
struct subsys_interface {
	const char *name;
	struct bus_type *subsys;
	struct list_head node;
	int (*add_dev)(struct device *dev, struct subsys_interface *sif);
	void (*remove_dev)(struct device *dev, struct subsys_interface *sif);
};

int subsys_interface_register(struct subsys_interface *sif);
void subsys_interface_unregister(struct subsys_interface *sif);

int subsys_system_register(struct bus_type *subsys,
			   const struct attribute_group **groups);
int subsys_virtual_register(struct bus_type *subsys,
			    const struct attribute_group **groups);

/*
 * The type of device, "struct device" is embedded in. A class
 * or bus can contain devices of different types
 * like "partitions" and "disks", "mouse" and "event".
 * This identifies the device type and carries type-specific
 * information, equivalent to the kobj_type of a kobject.
 * If "name" is specified, the uevent will contain it in
 * the DEVTYPE variable.
 */
struct device_type {
	const char *name;
	const struct attribute_group **groups;
	int (*uevent)(struct device *dev, struct kobj_uevent_env *env);
	char *(*devnode)(struct device *dev, umode_t *mode,
			 kuid_t *uid, kgid_t *gid);
	void (*release)(struct device *dev);

	const struct dev_pm_ops *pm;
};

/* interface for exporting device attributes */
struct device_attribute {
	struct attribute	attr;
	ssize_t (*show)(struct device *dev, struct device_attribute *attr,
			char *buf);
	ssize_t (*store)(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t count);
};

struct dev_ext_attribute {
	struct device_attribute attr;
	void *var;
};

ssize_t device_show_ulong(struct device *dev, struct device_attribute *attr,
			  char *buf);
ssize_t device_store_ulong(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count);
ssize_t device_show_int(struct device *dev, struct device_attribute *attr,
			char *buf);
ssize_t device_store_int(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t count);
ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
			char *buf);
ssize_t device_store_bool(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t count);

#define DEVICE_ATTR(_name, _mode, _show, _store) \
	struct device_attribute dev_attr_##_name = __ATTR(_name, _mode, _show, _store)
#define DEVICE_ATTR_PREALLOC(_name, _mode, _show, _store) \
	struct device_attribute dev_attr_##_name = \
		__ATTR_PREALLOC(_name, _mode, _show, _store)
#define DEVICE_ATTR_RW(_name) \
	struct device_attribute dev_attr_##_name = __ATTR_RW(_name)
#define DEVICE_ATTR_ADMIN_RW(_name) \
	struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600)
#define DEVICE_ATTR_RO(_name) \
	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
#define DEVICE_ATTR_ADMIN_RO(_name) \
	struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400)
#define DEVICE_ATTR_WO(_name) \
	struct device_attribute dev_attr_##_name = __ATTR_WO(_name)
#define DEVICE_ULONG_ATTR(_name, _mode, _var) \
	struct dev_ext_attribute dev_attr_##_name = \
		{ __ATTR(_name, _mode, device_show_ulong, device_store_ulong), &(_var) }
#define DEVICE_INT_ATTR(_name, _mode, _var) \
	struct dev_ext_attribute dev_attr_##_name = \
		{ __ATTR(_name, _mode, device_show_int, device_store_int), &(_var) }
#define DEVICE_BOOL_ATTR(_name, _mode, _var) \
	struct dev_ext_attribute dev_attr_##_name = \
		{ __ATTR(_name, _mode, device_show_bool, device_store_bool), &(_var) }
#define DEVICE_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
	struct device_attribute dev_attr_##_name =		\
		__ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)

int device_create_file(struct device *device,
		       const struct device_attribute *entry);
void device_remove_file(struct device *dev,
			const struct device_attribute *attr);
bool device_remove_file_self(