STRUCT ES58X_FD_URB_CMD(9)

🌸 NAME 🌸

okay so bestie, welcome to the Kernel API Manual page for struct es58x_fd_urb_cmd(9) 💖 and it's literally all about commands received from or sent to the ES58X FD device. no cap, that's the whole vibe.

✨ SYNOPSIS ✨

here's the struct in all its glory, pls admire the layout:

       struct es58x_fd_urb_cmd {
           __le16 SOF;
           u8 cmd_type;
           u8 cmd_id;
           u8 channel_idx;
           __le16 msg_len;
           union {
             struct es58x_fd_tx_conf_msg tx_conf_msg;
             u8 tx_can_msg_buf[ES58X_FD_TX_BULK_MAX * ES58X_FD_CANFD_TX_LEN];
             u8 rx_can_msg_buf[ES58X_FD_RX_BULK_MAX * ES58X_FD_CANFD_RX_LEN];
             struct es58x_fd_echo_msg echo_msg[ES58X_FD_ECHO_BULK_MAX];
             struct es58x_fd_rx_event_msg rx_event_msg;
             struct es58x_fd_tx_ack_msg tx_ack_msg;
             __le64 timestamp;
             __le32 rx_cmd_ret_le32;
             u8 raw_msg[];
           };
           __le16 reserved_for_crc16_do_not_use;
        };

🫶 Members 🫶

• SOF — Start of Frame. iconic little opener ✨
• cmd_type — Command Type (type: enum es58x_fd_cmd_type). and bestie, the CRC calculation starts at this position. noted. 💅
• cmd_id — Command ID (type: enum es58x_fd_cmd_id).
• channel_idx — Channel index starting at 0.
• msg_len — Length of the message, excluding CRC (i.e. length of the union).
• {unnamed_union} — anonymous. it's the union, no name needed 🫶
• tx_conf_msg — Channel configuration.
• tx_can_msg_buf — Concatenation of Tx messages. Type is "u8[]" instead of "struct es58x_fd_tx_msg[]" because the structure has a flexible size.
• rx_can_msg_buf — Concatenation Rx messages. Type is "u8[]" instead of "struct es58x_fd_rx_msg[]" because the structure has a flexible size.
• echo_msg — Array of echo messages (e.g. Tx messages being looped back).
• rx_event_msg — Error or event message.
• tx_ack_msg — Tx acknowledgment message.
• timestamp — Timestamp reply.
• rx_cmd_ret_le32 — Rx 32 bits return code (type: enum es58x_cmd_ret_code_u32).
• raw_msg — Message raw payload.
• reserved_for_crc16_do_not_use — The structure ends with a CRC16. Because the structures in above union are of variable lengths, we can not predict the offset of the CRC in advance. Use functions es58x_get_crc and es58x_set_crc to manipulate it. bestie, this one is giving "do not touch" energy for a reason 🙈

🔗 SEE ALSO 🔗

Kernel file ./drivers/net/can/usb/etas_es58x/es58x_fd.h, enum es58x_fd_ctrlmode(9), and struct es58x_fd_tx_conf_msg(9). those are the see-also besties, go say hi 💜

mwah 💋 this page comes from ./drivers/net/can/usb/etas_es58x, with the October 2026 date vibe — and that's the whole cute little footer fantasy, periodt. 🎀✨