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 <[email protected]> 7 * Kirti Wankhede <[email protected]> 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 }; 49 50 static inline struct mdev_device *to_mdev_device(struct device *dev) 51 { 52 return container_of(dev, struct mdev_device, dev); 53 } 54 55 /* interface for exporting mdev supported type attributes */ 56 struct mdev_type_attribute { 57 struct attribute attr; 58 ssize_t (*show)(struct mdev_type *mtype, 59 struct mdev_type_attribute *attr, char *buf); 60 ssize_t (*store)(struct mdev_type *mtype, 61 struct mdev_type_attribute *attr, const char *buf, 62 size_t count); 63 }; 64 65 #define MDEV_TYPE_ATTR_RO(_name) \ 66 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name) 67 #define MDEV_TYPE_ATTR_WO(_name) \ 68 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name) 69 70 /** 71 * struct mdev_driver - Mediated device driver 72 * @device_api: string to return for the device_api sysfs 73 * @probe: called when new device created 74 * @remove: called when device removed 75 * @get_available: Return the max number of instances that can be created 76 * @types_attrs: attributes to the type kobjects. 77 * @driver: device driver structure 78 **/ 79 struct mdev_driver { 80 const char *device_api; 81 int (*probe)(struct mdev_device *dev); 82 void (*remove)(struct mdev_device *dev); 83 unsigned int (*get_available)(struct mdev_type *mtype); 84 const struct attribute * const *types_attrs; 85 struct device_driver driver; 86 }; 87 88 int mdev_register_parent(struct mdev_parent *parent, struct device *dev, 89 struct mdev_driver *mdev_driver, struct mdev_type **types, 90 unsigned int nr_types); 91 void mdev_unregister_parent(struct mdev_parent *parent); 92 93 int mdev_register_driver(struct mdev_driver *drv); 94 void mdev_unregister_driver(struct mdev_driver *drv); 95 96 static inline struct device *mdev_dev(struct mdev_device *mdev) 97 { 98 return &mdev->dev; 99 } 100 101 #endif /* MDEV_H */ 102