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 #include <linux/device.h>
14 #include <linux/uuid.h>
15
16 struct mdev_type;
17
18 struct mdev_device {
19 struct device dev;
20 guid_t uuid;
21 struct list_head next;
22 struct mdev_type *type;
23 bool active;
24 };
25
26 struct mdev_type {
27 /* set by the driver before calling mdev_register parent: */
28 const char *sysfs_name;
29 const char *pretty_name;
30
31 /* set by the core, can be used drivers */
32 struct mdev_parent *parent;
33
34 /* internal only */
35 struct kobject kobj;
36 struct kobject *devices_kobj;
37 };
38
39 /* embedded into the struct device that the mdev devices hang off */
40 struct mdev_parent {
41 struct device *dev;
42 struct mdev_driver *mdev_driver;
43 struct kset *mdev_types_kset;
44 /* Synchronize device creation/removal with parent unregistration */
45 struct rw_semaphore unreg_sem;
46 struct mdev_type **types;
47 unsigned int nr_types;
48 atomic_t available_instances;
49 };
50
51 static inline struct mdev_device *to_mdev_device(struct device *dev)
52 {
53 return container_of(dev, struct mdev_device, dev);
54 }
55
56 /**
57 * struct mdev_driver - Mediated device driver
58 * @device_api: string to return for the device_api sysfs
59 * @max_instances: maximum number of instances supported (optional)
60 * @probe: called when new device created
61 * @remove: called when device removed
62 * @get_available: Return the max number of instances that can be created
63 * @show_description: Print a description of the mtype
64 * @driver: device driver structure
65 **/
66 struct mdev_driver {
67 const char *device_api;
68 unsigned int max_instances;
69 int (*probe)(struct mdev_device *dev);
70 void (*remove)(struct mdev_device *dev);
71 unsigned int (*get_available)(struct mdev_type *mtype);
72 ssize_t (*show_description)(struct mdev_type *mtype, char *buf);
73 struct device_driver driver;
74 };
75
76 int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
77 struct mdev_driver *mdev_driver, struct mdev_type **types,
78 unsigned int nr_types);
79 void mdev_unregister_parent(struct mdev_parent *parent);
80
81 int mdev_register_driver(struct mdev_driver *drv);
82 void mdev_unregister_driver(struct mdev_driver *drv);
83
84 static inline struct device *mdev_dev(struct mdev_device *mdev)
85 {
86 return &mdev->dev;
87 }
88
89 #endif /* MDEV_H */
90
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.