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 16 /* Parent device */ 17 struct parent_device { 18 struct device *dev; 19 const struct parent_ops *ops; 20 21 /* internal */ 22 struct kref ref; 23 struct mutex lock; 24 struct list_head next; 25 struct kset *mdev_types_kset; 26 struct list_head type_list; 27 }; 28 29 /* Mediated device */ 30 struct mdev_device { 31 struct device dev; 32 struct parent_device *parent; 33 uuid_le uuid; 34 void *driver_data; 35 36 /* internal */ 37 struct kref ref; 38 struct list_head next; 39 struct kobject *type_kobj; 40 }; 41 42 /** 43 * struct parent_ops - Structure to be registered for each parent device to 44 * register the device to mdev module. 45 * 46 * @owner: The module owner. 47 * @dev_attr_groups: Attributes of the parent device. 48 * @mdev_attr_groups: Attributes of the mediated device. 49 * @supported_type_groups: Attributes to define supported types. It is mandatory 50 * to provide supported types. 51 * @create: Called to allocate basic resources in parent device's 52 * driver for a particular mediated device. It is 53 * mandatory to provide create ops. 54 * @kobj: kobject of type for which 'create' is called. 55 * @mdev: mdev_device structure on of mediated device 56 * that is being created 57 * Returns integer: success (0) or error (< 0) 58 * @remove: Called to free resources in parent device's driver for a 59 * a mediated device. It is mandatory to provide 'remove' 60 * ops. 61 * @mdev: mdev_device device structure which is being 62 * destroyed 63 * Returns integer: success (0) or error (< 0) 64 * @open: Open mediated device. 65 * @mdev: mediated device. 66 * Returns integer: success (0) or error (< 0) 67 * @release: release mediated device 68 * @mdev: mediated device. 69 * @read: Read emulation callback 70 * @mdev: mediated device structure 71 * @buf: read buffer 72 * @count: number of bytes to read 73 * @ppos: address. 74 * Retuns number on bytes read on success or error. 75 * @write: Write emulation callback 76 * @mdev: mediated device structure 77 * @buf: write buffer 78 * @count: number of bytes to be written 79 * @ppos: address. 80 * Retuns number on bytes written on success or error. 81 * @ioctl: IOCTL callback 82 * @mdev: mediated device structure 83 * @cmd: ioctl command 84 * @arg: arguments to ioctl 85 * @mmap: mmap callback 86 * @mdev: mediated device structure 87 * @vma: vma structure 88 * Parent device that support mediated device should be registered with mdev 89 * module with parent_ops structure. 90 **/ 91 92 struct parent_ops { 93 struct module *owner; 94 const struct attribute_group **dev_attr_groups; 95 const struct attribute_group **mdev_attr_groups; 96 struct attribute_group **supported_type_groups; 97 98 int (*create)(struct kobject *kobj, struct mdev_device *mdev); 99 int (*remove)(struct mdev_device *mdev); 100 int (*open)(struct mdev_device *mdev); 101 void (*release)(struct mdev_device *mdev); 102 ssize_t (*read)(struct mdev_device *mdev, char __user *buf, 103 size_t count, loff_t *ppos); 104 ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, 105 size_t count, loff_t *ppos); 106 ssize_t (*ioctl)(struct mdev_device *mdev, unsigned int cmd, 107 unsigned long arg); 108 int (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma); 109 }; 110 111 /* interface for exporting mdev supported type attributes */ 112 struct mdev_type_attribute { 113 struct attribute attr; 114 ssize_t (*show)(struct kobject *kobj, struct device *dev, char *buf); 115 ssize_t (*store)(struct kobject *kobj, struct device *dev, 116 const char *buf, size_t count); 117 }; 118 119 #define MDEV_TYPE_ATTR(_name, _mode, _show, _store) \ 120 struct mdev_type_attribute mdev_type_attr_##_name = \ 121 __ATTR(_name, _mode, _show, _store) 122 #define MDEV_TYPE_ATTR_RW(_name) \ 123 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name) 124 #define MDEV_TYPE_ATTR_RO(_name) \ 125 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name) 126 #define MDEV_TYPE_ATTR_WO(_name) \ 127 struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name) 128 129 /** 130 * struct mdev_driver - Mediated device driver 131 * @name: driver name 132 * @probe: called when new device created 133 * @remove: called when device removed 134 * @driver: device driver structure 135 * 136 **/ 137 struct mdev_driver { 138 const char *name; 139 int (*probe)(struct device *dev); 140 void (*remove)(struct device *dev); 141 struct device_driver driver; 142 }; 143 144 #define to_mdev_driver(drv) container_of(drv, struct mdev_driver, driver) 145 #define to_mdev_device(dev) container_of(dev, struct mdev_device, dev) 146 147 static inline void *mdev_get_drvdata(struct mdev_device *mdev) 148 { 149 return mdev->driver_data; 150 } 151 152 static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data) 153 { 154 mdev->driver_data = data; 155 } 156 157 extern struct bus_type mdev_bus_type; 158 159 #define dev_is_mdev(d) ((d)->bus == &mdev_bus_type) 160 161 extern int mdev_register_device(struct device *dev, 162 const struct parent_ops *ops); 163 extern void mdev_unregister_device(struct device *dev); 164 165 extern int mdev_register_driver(struct mdev_driver *drv, struct module *owner); 166 extern void mdev_unregister_driver(struct mdev_driver *drv); 167 168 #endif /* MDEV_H */ 169