telem_open(9)

💖 telem_open(9) — Kernel API Manual 💖

okay so bestie, welcome to the Kernel API Manual corner of the group chat 🫶 today's main character is telem_open, and yes she is iconic.

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🎀 NAME 🎀

telem_open — callback for when the device node is opened. literally the moment that node gets opened, this callback is on the scene 💅

✨ SYNOPSIS ✨

int telem_open (struct inode *inode , struct file *filp );

🫶 ARGUMENTS 🫶

• inode — the inode for this char device node. that's the node's little identity card, no cap.
• filp — the file for this char device node. iykyk 🦋

🌸 DESCRIPTION 🌸

okay so here's the reason this whole thing exists: we need to ensure that after writing a command to the device, the same userspace process reads the corresponding result. like, same process, same result, no chaotic crossover energy 😭

therefore, we increment a refcount on opening the device, so that only one process can communicate with the EC at a time. periodt 💅 that refcount is doing the most, and honestly? good for her.

💅 RETURN 💅

0 on success, or negative error code on failure. slay when it works, negative error code when it doesn't 💀

🔥 SEE ALSO 🔥

go read these too, bestie — they're all part of the lore:

• Kernel file ./drivers/platform/chrome/wilco_ec/telemetry.c
• struct wilco_ec_telem_request(9)
• check_telem_request(9)
• struct telem_device_data(9)
• struct telem_session_data(9)
• telem_device_free(9)
• telem_device_probe(9)

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💌 and that's the page, bestie — source/version ./drivers/platform/chrome/wilc..., dated October 2026, signing off with telem_open(9) energy 🫶✨