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         data[8] QEMU_ALIGNED(8);
  50 } qemu_can_frame;
  51
  52 /* Keep defines for QEMU separate from Linux ones for now */
  53
  54 #define QEMU_CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
  55 #define QEMU_CAN_RTR_FLAG 0x40000000U /* remote transmission request */
  56 #define QEMU_CAN_ERR_FLAG 0x20000000U /* error message frame */
  57
  58 #define QEMU_CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
  59 #define QEMU_CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
  60
  61 /**
  62  * struct qemu_can_filter - CAN ID based filter in can_register().
  63  * @can_id:   relevant bits of CAN ID which are not masked out.
  64  * @can_mask: CAN mask (see description)
  65  *
  66  * Description:
  67  * A filter matches, when
  68  *
  69  *          <received_can_id> & mask == can_id & mask
  70  *
  71  * The filter can be inverted (QEMU_CAN_INV_FILTER bit set in can_id) or it can
  72  * filter for error message frames (QEMU_CAN_ERR_FLAG bit set in mask).
  73  */
  74 typedef struct qemu_can_filter {
  75     qemu_canid_t    can_id;
  76     qemu_canid_t    can_mask;
  77 } qemu_can_filter;
  78
  79 /* QEMU_CAN_INV_FILTER can be set in qemu_can_filter.can_id */
  80 #define QEMU_CAN_INV_FILTER 0x20000000U
  81
  82 typedef struct CanBusClientState CanBusClientState;
  83 typedef struct CanBusState CanBusState;
  84
  85 typedef struct CanBusClientInfo {
  86     bool (*can_receive)(CanBusClientState *);
  87     ssize_t (*receive)(CanBusClientState *,
  88         const struct qemu_can_frame *frames, size_t frames_cnt);
  89 } CanBusClientInfo;
  90
  91 struct CanBusClientState {
  92     CanBusClientInfo *info;
  93     CanBusState *bus;
  94     int link_down;
  95     QTAILQ_ENTRY(CanBusClientState) next;
  96     CanBusClientState *peer;
  97     char *model;
  98     char *name;
  99     void (*destructor)(CanBusClientState *);
 100 };
 101
 102 #define TYPE_CAN_BUS "can-bus"
 103 #define CAN_BUS_CLASS(klass) \
 104      OBJECT_CLASS_CHECK(CanBusClass, (klass), TYPE_CAN_BUS)
 105 #define CAN_BUS_GET_CLASS(obj) \
 106      OBJECT_GET_CLASS(CanBusClass, (obj), TYPE_CAN_BUS)
 107 #define CAN_BUS(obj) \
 108      OBJECT_CHECK(CanBusState, (obj), TYPE_CAN_BUS)
 109
 110 int can_bus_filter_match(struct qemu_can_filter *filter, qemu_canid_t can_id);
 111
 112 int can_bus_insert_client(CanBusState *bus, CanBusClientState *client);
 113
 114 int can_bus_remove_client(CanBusClientState *client);
 115
 116 ssize_t can_bus_client_send(CanBusClientState *,
 117                             const struct qemu_can_frame *frames,
 118                             size_t frames_cnt);
 119
 120 int can_bus_client_set_filters(CanBusClientState *,
 121                                const struct qemu_can_filter *filters,
 122                                size_t filters_cnt);
 123
 124 #endif