diff --git a/include/net/can_emu.h b/include/net/can_emu.h index cab98ee8ec..6f9b206bb5 100644 --- a/include/net/can_emu.h +++ b/include/net/can_emu.h @@ -122,4 +122,8 @@ int can_bus_client_set_filters(CanBusClientState *, const struct qemu_can_filter *filters, size_t filters_cnt); +uint8_t can_dlc2len(uint8_t can_dlc); + +uint8_t can_len2dlc(uint8_t len); + #endif diff --git a/net/can/can_core.c b/net/can/can_core.c index 90f4d8576a..0115d78794 100644 --- a/net/can/can_core.c +++ b/net/can/can_core.c @@ -33,6 +33,42 @@ #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;