qemu/net/can/can_core.c

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/*
* CAN common CAN bus emulation support
*
* Copyright (c) 2013-2014 Jin Yang
* Copyright (c) 2014-2018 Pavel Pisa
*
* Initial development supported by Google GSoC 2013 from RTEMS project slot
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "chardev/char.h"
#include "qemu/module.h"
#include "qemu/sockets.h"
#include "qapi/error.h"
#include "net/can_emu.h"
#include "qom/object_interfaces.h"
/* CAN DLC to real data length conversion helpers */
static const uint8_t dlc2len[] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 12, 16, 20, 24, 32, 48, 64
};
/* get data length from can_dlc with sanitized can_dlc */
uint8_t can_dlc2len(uint8_t can_dlc)
{
return dlc2len[can_dlc & 0x0F];
}
static const uint8_t len2dlc[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
9, 9, 9, 9, /* 9 - 12 */
10, 10, 10, 10, /* 13 - 16 */
11, 11, 11, 11, /* 17 - 20 */
12, 12, 12, 12, /* 21 - 24 */
13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
15, 15, 15, 15, 15, 15, 15, 15 /* 57 - 64 */
};
/* map the sanitized data length to an appropriate data length code */
uint8_t can_len2dlc(uint8_t len)
{
if (unlikely(len > 64)) {
return 0xF;
}
return len2dlc[len];
}
struct CanBusState {
Object object;
QTAILQ_HEAD(, CanBusClientState) clients;
};
static void can_bus_instance_init(Object *object)
{
CanBusState *bus = (CanBusState *)object;
QTAILQ_INIT(&bus->clients);
}
int can_bus_insert_client(CanBusState *bus, CanBusClientState *client)
{
client->bus = bus;
QTAILQ_INSERT_TAIL(&bus->clients, client, next);
return 0;
}
int can_bus_remove_client(CanBusClientState *client)
{
CanBusState *bus = client->bus;
if (bus == NULL) {
return 0;
}
QTAILQ_REMOVE(&bus->clients, client, next);
client->bus = NULL;
return 1;
}
ssize_t can_bus_client_send(CanBusClientState *client,
const struct qemu_can_frame *frames, size_t frames_cnt)
{
int ret = 0;
CanBusState *bus = client->bus;
CanBusClientState *peer;
if (bus == NULL) {
return -1;
}
QTAILQ_FOREACH(peer, &bus->clients, next) {
if (peer->info->can_receive(peer)) {
if (peer == client) {
/* No loopback support for now */
continue;
}
if (peer->info->receive(peer, frames, frames_cnt) > 0) {
ret = 1;
}
}
}
return ret;
}
int can_bus_filter_match(struct qemu_can_filter *filter, qemu_canid_t can_id)
{
int m;
if (((can_id | filter->can_mask) & QEMU_CAN_ERR_FLAG)) {
return (filter->can_mask & QEMU_CAN_ERR_FLAG) != 0;
}
m = (can_id & filter->can_mask) == (filter->can_id & filter->can_mask);
return filter->can_id & QEMU_CAN_INV_FILTER ? !m : m;
}
int can_bus_client_set_filters(CanBusClientState *client,
const struct qemu_can_filter *filters, size_t filters_cnt)
{
return 0;
}
static bool can_bus_can_be_deleted(UserCreatable *uc)
{
return false;
}
static void can_bus_class_init(ObjectClass *klass,
void *class_data G_GNUC_UNUSED)
{
UserCreatableClass *uc_klass = USER_CREATABLE_CLASS(klass);
uc_klass->can_be_deleted = can_bus_can_be_deleted;
}
static const TypeInfo can_bus_info = {
.parent = TYPE_OBJECT,
.name = TYPE_CAN_BUS,
.instance_size = sizeof(CanBusState),
.instance_init = can_bus_instance_init,
.class_init = can_bus_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void can_bus_register_types(void)
{
type_register_static(&can_bus_info);
}
type_init(can_bus_register_types);