include/net/can_emu.h

   1 /*
   2  * CAN common CAN bus emulation support
   3  *
   4  * Copyright (c) 2013-2014 Jin Yang
   5  * Copyright (c) 2014-2018 Pavel Pisa
   6  *
   7  * Initial development supported by Google GSoC 2013 from RTEMS project slot
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a copy
  10  * of this software and associated documentation files (the "Software"), to deal
  11  * in the Software without restriction, including without limitation the rights
  12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13  * copies of the Software, and to permit persons to whom the Software is
  14  * furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included in
  17  * all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  25  * THE SOFTWARE.
  26  */
  27
  28 #ifndef NET_CAN_EMU_H
  29 #define NET_CAN_EMU_H
  30
  31 #include "qemu/queue.h"
  32 #include "qom/object.h"
  33
  34 /* NOTE: the following two structures is copied from <linux/can.h>. */
  35
  36 /*
  37  * Controller Area Network Identifier structure
  38  *
  39  * bit 0-28    : CAN identifier (11/29 bit)
  40  * bit 29      : error frame flag (0 = data frame, 1 = error frame)
  41  * bit 30      : remote transmission request flag (1 = rtr frame)
  42  * bit 31      : frame format flag (0 = standard 11 bit, 1 = extended 29 bit)
  43  */
  44 typedef uint32_t qemu_canid_t;
  45
  46 typedef struct qemu_can_frame {
  47     qemu_canid_t    can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
  48     uint8_t         can_dlc; /* data length code: 0 .. 8 */
  49     uint8_t         flags;
  50     uint8_t         data[64] QEMU_ALIGNED(8);
  51 } qemu_can_frame;
  52
  53 /* Keep defines for QEMU separate from Linux ones for now */
  54
  55 #define QEMU_CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
  56 #define QEMU_CAN_RTR_FLAG 0x40000000U /* remote transmission request */
  57 #define QEMU_CAN_ERR_FLAG 0x20000000U /* error message frame */
  58
  59 #define QEMU_CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
  60 #define QEMU_CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
  61
  62 #define QEMU_CAN_FRMF_BRS     0x01 /* bit rate switch (2nd bitrate for data) */
  63 #define QEMU_CAN_FRMF_ESI     0x02 /* error state ind. of transmitting node */
  64 #define QEMU_CAN_FRMF_TYPE_FD 0x10 /* internal bit ind. of CAN FD frame */
  65
  66 /**
  67  * struct qemu_can_filter - CAN ID based filter in can_register().
  68  * @can_id:   relevant bits of CAN ID which are not masked out.
  69  * @can_mask: CAN mask (see description)
  70  *
  71  * Description:
  72  * A filter matches, when
  73  *
  74  *          <received_can_id> & mask == can_id & mask
  75  *
  76  * The filter can be inverted (QEMU_CAN_INV_FILTER bit set in can_id) or it can
  77  * filter for error message frames (QEMU_CAN_ERR_FLAG bit set in mask).
  78  */
  79 typedef struct qemu_can_filter {
  80     qemu_canid_t    can_id;
  81     qemu_canid_t    can_mask;
  82 } qemu_can_filter;
  83
  84 /* QEMU_CAN_INV_FILTER can be set in qemu_can_filter.can_id */
  85 #define QEMU_CAN_INV_FILTER 0x20000000U
  86
  87 typedef struct CanBusClientState CanBusClientState;
  88 typedef struct CanBusState CanBusState;
  89
  90 typedef struct CanBusClientInfo {
  91     bool (*can_receive)(CanBusClientState *);
  92     ssize_t (*receive)(CanBusClientState *,
  93         const struct qemu_can_frame *frames, size_t frames_cnt);
  94 } CanBusClientInfo;
  95
  96 struct CanBusClientState {
  97     CanBusClientInfo *info;
  98     CanBusState *bus;
  99     int link_down;
 100     QTAILQ_ENTRY(CanBusClientState) next;
 101     CanBusClientState *peer;
 102     char *model;
 103     char *name;
 104     void (*destructor)(CanBusClientState *);
 105     bool fd_mode;
 106 };
 107
 108 #define TYPE_CAN_BUS "can-bus"
 109 OBJECT_DECLARE_SIMPLE_TYPE(CanBusState, CAN_BUS)
 110
 111 int can_bus_filter_match(struct qemu_can_filter *filter, qemu_canid_t can_id);
 112
 113 int can_bus_insert_client(CanBusState *bus, CanBusClientState *client);
 114
 115 int can_bus_remove_client(CanBusClientState *client);
 116
 117 ssize_t can_bus_client_send(CanBusClientState *,
 118                             const struct qemu_can_frame *frames,
 119                             size_t frames_cnt);
 120
 121 int can_bus_client_set_filters(CanBusClientState *,
 122                                const struct qemu_can_filter *filters,
 123                                size_t filters_cnt);
 124
 125 uint8_t can_dlc2len(uint8_t can_dlc);
 126
 127 uint8_t can_len2dlc(uint8_t len);
 128
 129 #endif