hdlc_encoded_length(9)

💖 hdlc_encoded_length(9) — Kernel API Manual 💖

✨ NAME ✨

hdlc_encoded_length — Calculate worst-case encoded length of an HDLC frame. Bestie, it’s literally the “how big could this get” function for an HDLC frame, no cap.

🌸 SYNOPSIS 🌸

size_t hdlc_encoded_length (const struct hdlc_payload payloads[] , size_t count );

🎀 ARGUMENTS 🎀

• payloads — array of payload buffers. It’s the lineup of buffers you’re handing over, fr fr.
• count — number of payloads. Basically how many buffers are in that array, periodt.

💅 DESCRIPTION 💅

Okay so every data byte may need HDLC escaping, and escaping can double its size — that’s the whole reason this is a worst-case calculation, iykyk.

The frame layout is giving:

flag(1) + address(1-2) + control(1-2) + payload + CRC(2-4) + flag(1)

It returns the maximum number of bytes needed in the circular buffer. That’s the whole slay: max bytes, circular buffer, done. 💅

🦋 SEE ALSO 🦋

Kernel file ./drivers/greybus/gb-beagleplay.c is right there in the mix, and the whole squad is:

• struct gb_beagleplay(9)
• struct hdlc_payload(9)
• struct hdlc_greybus_frame(9)
• enum cc1352_bootloader_cmd(9)
• enum cc1352_bootloader_status(9)
• struct cc1352_bootloader_packet(9)
• struct cc1352_bootloader_download_cmd_data(9)
• struct cc1352_bootloader_crc32_cmd_data(9)
• hdlc_write(9)
• hdlc_append(9)
• hdlc_tx_frames(9)
• csum8(9)
• cc1352_bootloader_pkt_rx(9)
• gb_message_send(9)
• cc1352_bootloader_empty_pkt(9)

💖 that’s the tea, bestie — source/version ./drivers/greybus, date October 2026. The Kernel API Manual ate, and hdlc_encoded_length(9) is iconic. periodt. 💖