builtin_i2c_driver(9)

💜 builtin_i2c_driver — the Kernel API Manual page you didn't know you needed

okay bestie, so this is builtin_i2c_driver(9) from the Kernel API Manual, and honestly? it's a tiny little macro that saves you so much typing. let's get into it ✨

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🌸 NAME 🌸

builtin_i2c_driver — the helper macro for registering a builtin I2C driver, no cap 🎀

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🦋 SYNOPSIS 🦋

builtin_i2c_driver (__i2c_driver );

that's literally it. one macro, one argument, she's serving minimalism 💅

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⭐ ARGUMENTS ⭐

• __i2c_driver — an i2c_driver struct. that's the whole thing. that's the argument. hand her the struct and she handles the rest 🫶

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✨ DESCRIPTION ✨

okay so picture this: you're writing an I2C driver, and your init function does absolutely nothing special — it's just boilerplate city 🏙️. this macro is your girl. builtin_i2c_driver is a helper macro for I2C drivers which do not do anything special in their init, and the way that it eliminates a lot of boilerplate is genuinely iconic 🔥

two things you gotta remember though, and i mean it:

• each driver may only use this macro once. one and done. periodt 💀
• calling it replaces device_initcall — so like, don't go doubling up, iykyk 🙈

bestie please respect the once-only rule. it's not a suggestion, it's the whole vibe check 🧚

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👑 SEE ALSO 👑

the kernel file ./include/linux/i2c.h is where the magic lives, and here's the full squad she runs with — all of these, no skips, because they're all part of the family 🌈:

• i2c_master_recv(9)
• i2c_master_recv_dmasafe(9)
• i2c_master_send(9)
• i2c_master_send_dmasafe(9)
• struct i2c_device_identity(9)
• enum i2c_driver_flags(9)
• struct i2c_driver(9)
• struct i2c_client(9)
• struct i2c_board_info(9)
• I2C_BOARD_INFO(9)
• struct i2c_algorithm(9)
• struct i2c_lock_operations(9)
• struct i2c_timings(9)
• struct i2c_bus_recovery_info(9)
• struct i2c_adapter_quirks(9)
• i2c_lock_bus(9)
• i2c_trylock_bus(9)
• i2c_unlock_bus(9)
• i2c_mark_adapter_suspended(9)
• i2c_mark_adapter_resumed(9)
• i2c_check_quirks(9)
• module_i2c_driver(9)

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that's the whole page, bestie — short, sweet, and highkey a lifesaver 💖 this gem comes from the kernel source at ./include/linux, dated October 2026, and it's brought to you by the Kernel API Manual ✨ mwah, go register some drivers 🎀🦋