sdw_transfer_defer(9)

🦋 sdw_transfer_defer — the kernel API manual, bestie edition 🦋

okay so real talk, this is sdw_transfer_defer(9) from the Kernel API Manual and it's lowkey the most chill way to send a message to a SoundWire (SDW) Slave device without standing around waiting for it 💅

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✨ NAME ✨

sdw_transfer_defer — asynchronously transfer a message to a SDW Slave device. like, you hand it off and go live your life, no cap 🫶

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🌸 SYNOPSIS 🌸

int sdw_transfer_defer (struct sdw_bus *bus , struct sdw_msg *msg );

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🎀 ARGUMENTS 🎀

• bus — the SDW bus. your ride. the main character of the wiring situation 🚌
• msg — the SDW message to be xfered (yes that's the manpage's spelling, we keep it, it's iconic) 💌

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💖 DESCRIPTION 💖

So here's the thing: the caller needs to hold the msg_lock lock while calling this. that's not a vibe suggestion, that's the rule, fr fr 🔒

⚠️ no msg_lock, no transfer. please don't skip this step bestie, the kernel will not be cute about it 😭

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👑 SEE ALSO 👑

Kernel file ./drivers/soundwire/bus.c — plus the whole friend group, they all said hi:

• sdw_bus_master_add(9)
• sdw_bus_master_delete(9)
• sdw_transfer(9)
• sdw_show_ping_status(9)
• sdw_nread_no_pm(9)
• sdw_nwrite_no_pm(9)
• sdw_write_no_pm(9)
• sdw_read_no_pm(9)
• sdw_nread(9)
• sdw_nwrite(9)
• sdw_read(9)
• sdw_write(9)
• sdw_bus_prep_clk_stop(9)
• sdw_bus_clk_stop(9)
• sdw_bus_exit_clk_stop(9)
• sdw_handle_slave_status(9)

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and that's the whole page, periodt ✨ this cutie lives in ./drivers/soundwire, dated October 2026, and it's filed under sdw_transfer_defer(9) — mwah, go transfer some messages asynchronously 💋🌸