include/linux/rpmb.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (C) 2015-2019 Intel Corp. All rights reserved
   4  * Copyright (C) 2021-2022 Linaro Ltd
   5  */
   6 #ifndef __RPMB_H__
   7 #define __RPMB_H__
   8
   9 #include <linux/device.h>
  10 #include <linux/types.h>
  11
  12 /**
  13  * enum rpmb_type - type of underlying storage technology
  14  *
  15  * @RPMB_TYPE_EMMC  : emmc (JESD84-B50.1)
  16  * @RPMB_TYPE_UFS   : UFS (JESD220)
  17  * @RPMB_TYPE_NVME  : NVM Express
  18  */
  19 enum rpmb_type {
  20         RPMB_TYPE_EMMC,
  21         RPMB_TYPE_UFS,
  22         RPMB_TYPE_NVME,
  23 };
  24
  25 /**
  26  * struct rpmb_descr - RPMB description provided by the underlying block device
  27  *
  28  * @type             : block device type
  29  * @route_frames     : routes frames to and from the RPMB device
  30  * @dev_id           : unique device identifier read from the hardware
  31  * @dev_id_len       : length of unique device identifier
  32  * @reliable_wr_count: number of sectors that can be written in one access
  33  * @capacity         : capacity of the device in units of 128K
  34  *
  35  * @dev_id is intended to be used as input when deriving the authenticaion key.
  36  */
  37 struct rpmb_descr {
  38         enum rpmb_type type;
  39         int (*route_frames)(struct device *dev, u8 *req, unsigned int req_len,
  40                             u8 *resp, unsigned int resp_len);
  41         u8 *dev_id;
  42         size_t dev_id_len;
  43         u16 reliable_wr_count;
  44         u16 capacity;
  45 };
  46
  47 /**
  48  * struct rpmb_dev - device which can support RPMB partition
  49  *
  50  * @dev              : device
  51  * @id               : device_id
  52  * @list_node        : linked list node
  53  * @descr            : RPMB description
  54  */
  55 struct rpmb_dev {
  56         struct device dev;
  57         int id;
  58         struct list_head list_node;
  59         struct rpmb_descr descr;
  60 };
  61
  62 #define to_rpmb_dev(x)          container_of((x), struct rpmb_dev, dev)
  63
  64 #if IS_ENABLED(CONFIG_RPMB)
  65 struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev);
  66 void rpmb_dev_put(struct rpmb_dev *rdev);
  67 struct rpmb_dev *rpmb_dev_find_device(const void *data,
  68                                       const struct rpmb_dev *start,
  69                                       int (*match)(struct device *dev,
  70                                                    const void *data));
  71 int rpmb_interface_register(struct class_interface *intf);
  72 void rpmb_interface_unregister(struct class_interface *intf);
  73 struct rpmb_dev *rpmb_dev_register(struct device *dev,
  74                                    struct rpmb_descr *descr);
  75 int rpmb_dev_unregister(struct rpmb_dev *rdev);
  76
  77 int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
  78                       unsigned int req_len, u8 *resp, unsigned int resp_len);
  79
  80 #else
  81 static inline struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev)
  82 {
  83         return NULL;
  84 }
  85
  86 static inline void rpmb_dev_put(struct rpmb_dev *rdev) { }
  87
  88 static inline struct rpmb_dev *
  89 rpmb_dev_find_device(const void *data, const struct rpmb_dev *start,
  90                      int (*match)(struct device *dev, const void *data))
  91 {
  92         return NULL;
  93 }
  94
  95 static inline int rpmb_interface_register(struct class_interface *intf)
  96 {
  97         return -EOPNOTSUPP;
  98 }
  99
 100 static inline void rpmb_interface_unregister(struct class_interface *intf)
 101 {
 102 }
 103
 104 static inline struct rpmb_dev *
 105 rpmb_dev_register(struct device *dev, struct rpmb_descr *descr)
 106 {
 107         return NULL;
 108 }
 109
 110 static inline int rpmb_dev_unregister(struct rpmb_dev *dev)
 111 {
 112         return 0;
 113 }
 114
 115 static inline int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
 116                                     unsigned int req_len, u8 *resp,
 117                                     unsigned int resp_len)
 118 {
 119         return -EOPNOTSUPP;
 120 }
 121 #endif /* CONFIG_RPMB */
 122
 123 #endif /* __RPMB_H__ */