1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Mediated device definition
4 *
5 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
6 * Author: Neo Jia <cjia@nvidia.com>
7 * Kirti Wankhede <kwankhede@nvidia.com>
8 */
9
10 #ifndef MDEV_H
11 #define MDEV_H
12
13 struct mdev_type;
14
15 struct mdev_device {
16 struct device dev;
17 guid_t uuid;
18 void *driver_data;
19 struct list_head next;
20 struct mdev_type *type;
21 bool active;
22 };
23
to_mdev_device(struct device * dev)24 static inline struct mdev_device *to_mdev_device(struct device *dev)
25 {
26 return container_of(dev, struct mdev_device, dev);
27 }
28
29 unsigned int mdev_get_type_group_id(struct mdev_device *mdev);
30 unsigned int mtype_get_type_group_id(struct mdev_type *mtype);
31 struct device *mtype_get_parent_dev(struct mdev_type *mtype);
32
33 /**
34 * struct mdev_parent_ops - Structure to be registered for each parent device to
35 * register the device to mdev module.
36 *
37 * @owner: The module owner.
38 * @device_driver: Which device driver to probe() on newly created devices
39 * @dev_attr_groups: Attributes of the parent device.
40 * @mdev_attr_groups: Attributes of the mediated device.
41 * @supported_type_groups: Attributes to define supported types. It is mandatory
42 * to provide supported types.
43 * @create: Called to allocate basic resources in parent device's
44 * driver for a particular mediated device. It is
45 * mandatory to provide create ops.
46 * @mdev: mdev_device structure on of mediated device
47 * that is being created
48 * Returns integer: success (0) or error (< 0)
49 * @remove: Called to free resources in parent device's driver for
50 * a mediated device. It is mandatory to provide 'remove'
51 * ops.
52 * @mdev: mdev_device device structure which is being
53 * destroyed
54 * Returns integer: success (0) or error (< 0)
55 * @read: Read emulation callback
56 * @mdev: mediated device structure
57 * @buf: read buffer
58 * @count: number of bytes to read
59 * @ppos: address.
60 * Retuns number on bytes read on success or error.
61 * @write: Write emulation callback
62 * @mdev: mediated device structure
63 * @buf: write buffer
64 * @count: number of bytes to be written
65 * @ppos: address.
66 * Retuns number on bytes written on success or error.
67 * @ioctl: IOCTL callback
68 * @mdev: mediated device structure
69 * @cmd: ioctl command
70 * @arg: arguments to ioctl
71 * @mmap: mmap callback
72 * @mdev: mediated device structure
73 * @vma: vma structure
74 * @request: request callback to release device
75 * @mdev: mediated device structure
76 * @count: request sequence number
77 * Parent device that support mediated device should be registered with mdev
78 * module with mdev_parent_ops structure.
79 **/
80 struct mdev_parent_ops {
81 struct module *owner;
82 struct mdev_driver *device_driver;
83 const struct attribute_group **dev_attr_groups;
84 const struct attribute_group **mdev_attr_groups;
85 struct attribute_group **supported_type_groups;
86
87 int (*create)(struct mdev_device *mdev);
88 int (*remove)(struct mdev_device *mdev);
89 int (*open_device)(struct mdev_device *mdev);
90 void (*close_device)(struct mdev_device *mdev);
91 ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
92 size_t count, loff_t *ppos);
93 ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
94 size_t count, loff_t *ppos);
95 long (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
96 unsigned long arg);
97 int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
98 void (*request)(struct mdev_device *mdev, unsigned int count);
99 };
100
101 /* interface for exporting mdev supported type attributes */
102 struct mdev_type_attribute {
103 struct attribute attr;
104 ssize_t (*show)(struct mdev_type *mtype,
105 struct mdev_type_attribute *attr, char *buf);
106 ssize_t (*store)(struct mdev_type *mtype,
107 struct mdev_type_attribute *attr, const char *buf,
108 size_t count);
109 };
110
111 #define MDEV_TYPE_ATTR(_name, _mode, _show, _store) \
112 struct mdev_type_attribute mdev_type_attr_##_name = \
113 __ATTR(_name, _mode, _show, _store)
114 #define MDEV_TYPE_ATTR_RW(_name) \
115 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
116 #define MDEV_TYPE_ATTR_RO(_name) \
117 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
118 #define MDEV_TYPE_ATTR_WO(_name) \
119 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
120
121 /**
122 * struct mdev_driver - Mediated device driver
123 * @probe: called when new device created
124 * @remove: called when device removed
125 * @driver: device driver structure
126 *
127 **/
128 struct mdev_driver {
129 int (*probe)(struct mdev_device *dev);
130 void (*remove)(struct mdev_device *dev);
131 struct device_driver driver;
132 };
133
mdev_get_drvdata(struct mdev_device * mdev)134 static inline void *mdev_get_drvdata(struct mdev_device *mdev)
135 {
136 return mdev->driver_data;
137 }
mdev_set_drvdata(struct mdev_device * mdev,void * data)138 static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
139 {
140 mdev->driver_data = data;
141 }
mdev_uuid(struct mdev_device * mdev)142 static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
143 {
144 return &mdev->uuid;
145 }
146
147 extern struct bus_type mdev_bus_type;
148
149 int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops);
150 void mdev_unregister_device(struct device *dev);
151
152 int mdev_register_driver(struct mdev_driver *drv);
153 void mdev_unregister_driver(struct mdev_driver *drv);
154
155 struct device *mdev_parent_dev(struct mdev_device *mdev);
mdev_dev(struct mdev_device * mdev)156 static inline struct device *mdev_dev(struct mdev_device *mdev)
157 {
158 return &mdev->dev;
159 }
mdev_from_dev(struct device * dev)160 static inline struct mdev_device *mdev_from_dev(struct device *dev)
161 {
162 return dev->bus == &mdev_bus_type ? to_mdev_device(dev) : NULL;
163 }
164
165 #endif /* MDEV_H */
166