LXR linux/include/linux/mdev.h

   1/*
   2 * Mediated device definition
   3 *
   4 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
   5 *     Author: Neo Jia <cjia@nvidia.com>
   6 *             Kirti Wankhede <kwankhede@nvidia.com>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#ifndef MDEV_H
  14#define MDEV_H
  15
  16struct mdev_device;
  17
  18/**
  19 * struct mdev_parent_ops - Structure to be registered for each parent device to
  20 * register the device to mdev module.
  21 *
  22 * @owner:              The module owner.
  23 * @dev_attr_groups:    Attributes of the parent device.
  24 * @mdev_attr_groups:   Attributes of the mediated device.
  25 * @supported_type_groups: Attributes to define supported types. It is mandatory
  26 *                      to provide supported types.
  27 * @create:             Called to allocate basic resources in parent device's
  28 *                      driver for a particular mediated device. It is
  29 *                      mandatory to provide create ops.
  30 *                      @kobj: kobject of type for which 'create' is called.
  31 *                      @mdev: mdev_device structure on of mediated device
  32 *                            that is being created
  33 *                      Returns integer: success (0) or error (< 0)
  34 * @remove:             Called to free resources in parent device's driver for a
  35 *                      a mediated device. It is mandatory to provide 'remove'
  36 *                      ops.
  37 *                      @mdev: mdev_device device structure which is being
  38 *                             destroyed
  39 *                      Returns integer: success (0) or error (< 0)
  40 * @open:               Open mediated device.
  41 *                      @mdev: mediated device.
  42 *                      Returns integer: success (0) or error (< 0)
  43 * @release:            release mediated device
  44 *                      @mdev: mediated device.
  45 * @read:               Read emulation callback
  46 *                      @mdev: mediated device structure
  47 *                      @buf: read buffer
  48 *                      @count: number of bytes to read
  49 *                      @ppos: address.
  50 *                      Retuns number on bytes read on success or error.
  51 * @write:              Write emulation callback
  52 *                      @mdev: mediated device structure
  53 *                      @buf: write buffer
  54 *                      @count: number of bytes to be written
  55 *                      @ppos: address.
  56 *                      Retuns number on bytes written on success or error.
  57 * @ioctl:              IOCTL callback
  58 *                      @mdev: mediated device structure
  59 *                      @cmd: ioctl command
  60 *                      @arg: arguments to ioctl
  61 * @mmap:               mmap callback
  62 *                      @mdev: mediated device structure
  63 *                      @vma: vma structure
  64 * Parent device that support mediated device should be registered with mdev
  65 * module with mdev_parent_ops structure.
  66 **/
  67struct mdev_parent_ops {
  68        struct module   *owner;
  69        const struct attribute_group **dev_attr_groups;
  70        const struct attribute_group **mdev_attr_groups;
  71        struct attribute_group **supported_type_groups;
  72
  73        int     (*create)(struct kobject *kobj, struct mdev_device *mdev);
  74        int     (*remove)(struct mdev_device *mdev);
  75        int     (*open)(struct mdev_device *mdev);
  76        void    (*release)(struct mdev_device *mdev);
  77        ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
  78                        size_t count, loff_t *ppos);
  79        ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
  80                         size_t count, loff_t *ppos);
  81        long    (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
  82                         unsigned long arg);
  83        int     (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
  84};
  85
  86/* interface for exporting mdev supported type attributes */
  87struct mdev_type_attribute {
  88        struct attribute attr;
  89        ssize_t (*show)(struct kobject *kobj, struct device *dev, char *buf);
  90        ssize_t (*store)(struct kobject *kobj, struct device *dev,
  91                         const char *buf, size_t count);
  92};
  93
  94#define MDEV_TYPE_ATTR(_name, _mode, _show, _store)             \
  95struct mdev_type_attribute mdev_type_attr_##_name =             \
  96        __ATTR(_name, _mode, _show, _store)
  97#define MDEV_TYPE_ATTR_RW(_name) \
  98        struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
  99#define MDEV_TYPE_ATTR_RO(_name) \
 100        struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
 101#define MDEV_TYPE_ATTR_WO(_name) \
 102        struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
 103
 104/**
 105 * struct mdev_driver - Mediated device driver
 106 * @name: driver name
 107 * @probe: called when new device created
 108 * @remove: called when device removed
 109 * @driver: device driver structure
 110 *
 111 **/
 112struct mdev_driver {
 113        const char *name;
 114        int  (*probe)(struct device *dev);
 115        void (*remove)(struct device *dev);
 116        struct device_driver driver;
 117};
 118
 119#define to_mdev_driver(drv)     container_of(drv, struct mdev_driver, driver)
 120
 121extern void *mdev_get_drvdata(struct mdev_device *mdev);
 122extern void mdev_set_drvdata(struct mdev_device *mdev, void *data);
 123extern uuid_le mdev_uuid(struct mdev_device *mdev);
 124
 125extern struct bus_type mdev_bus_type;
 126
 127extern int  mdev_register_device(struct device *dev,
 128                                 const struct mdev_parent_ops *ops);
 129extern void mdev_unregister_device(struct device *dev);
 130
 131extern int  mdev_register_driver(struct mdev_driver *drv, struct module *owner);
 132extern void mdev_unregister_driver(struct mdev_driver *drv);
 133
 134extern struct device *mdev_parent_dev(struct mdev_device *mdev);
 135extern struct device *mdev_dev(struct mdev_device *mdev);
 136extern struct mdev_device *mdev_from_dev(struct device *dev);
 137
 138#endif /* MDEV_H */
 139