cros_ec_prepare_tx(9)

cros_ec_prepare_tx(9) 💖✨

okay bestie, welcome to the Kernel API Manual entry for cros_ec_prepare_tx(9) — yes, the one and only. this is the little helper that gets your outgoing ChromeOS EC message all cute and ready in the output buffer, no cap. 🫶

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🌸 NAME 🌸

cros_ec_prepare_tx — prepare an outgoing message in the output buffer. 💌

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✨ SYNOPSIS ✨

int cros_ec_prepare_tx (struct cros_ec_device *ec_dev , struct
       cros_ec_command *msg );

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🫶 ARGUMENTS 🫶

• ec_dev — device to register. literally that's the one.
• msg — message to write. the message itself, bestie. 📨

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💅 DESCRIPTION 💅

this is used by all ChromeOS EC drivers to prepare the outgoing message according to different protocol versions. so yeah, it's giving "universal prep step" energy: different protocol versions, same function doing the prep work. ✨

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🔥 RETURN 🔥

on success you get the number of prepared bytes — slay. on failure you get a negative error code, so if it's negative, that's your cue to be like "oop, error" 😭. periodt.

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🦋 SEE ALSO 🦋

• Kernel file: ./drivers/platform/chrome/cros_ec_proto.c
• cros_ec_check_result(9)
• cros_ec_get_host_event_wake_mask(9)
• cros_ec_get_host_command_version_mask(9)
• cros_ec_query_all(9)
• cros_ec_cmd_xfer(9)
• cros_ec_cmd_xfer_status(9)
• cros_ec_get_next_event(9)
• cros_ec_get_host_event(9)
• cros_ec_read_features(9)
• cros_ec_check_features(9)
• cros_ec_get_sensor_count(9)
• cros_ec_cmd(9)
• cros_ec_cmd_readmem(9)
• cros_ec_get_cmd_versions(9)
• cros_ec_device_registered(9)

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cute sign-off time 🎀: this page came from the source/version footer at ./drivers/platform/chrome, dated October 2026, for cros_ec_prepare_tx(9). byeee 💖🌷