uart_dtr_rts(9)

💖 uart_dtr_rts — like, the whole page ✨

okay so bestie, welcome to the uart_dtr_rts(9) page from the Kernel API Manual — yes that's the manual name, no I will not be normal about it. this is a lil port helper and it's honestly doing the most important little job, so let's get into it 🫶

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🌸 NAME 🌸

uart_dtr_rts — the port helper that sets uart signals. that's it, that's the whole vibe. it flips DTR and RTS for you and it does it flawlessly 💅

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⭐ SYNOPSIS ⭐

void uart_dtr_rts (struct tty_port *tport , bool active );

literally just one function, two arguments, zero drama. iconic behavior honestly 👑

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🦋 ARGUMENTS 🦋

• tport — the tty port that's getting updated. this is your main character, the thing you're poking at ✨
• active — set this to turn on DTR/RTS. so it's your on/off switch. setting it = signals ON, and you can lowkey guess what not setting it does 😌

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🎀 DESCRIPTION 🎀

so here's the tea: this gets called by the tty port helpers when the modem signals need adjusting during an open, a close, and a hangup. that's the three moments. that's the entire job description. it's giving "small but crucial role in the ecosystem" and we stan 🌈

no cap, it's a helper's helper — it doesn't go out and do stuff on its own, it gets summoned when the modem signals need a lil adjustment mid open, close or hangup. periodt 💜

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🔥 SEE ALSO 🔥

• the kernel file ./drivers/mmc/core/sdio_uart.c
• sdio_uart_activate(9)
• sdio_uart_shutdown(9)
• sdio_uart_install(9)
• sdio_uart_cleanup(9)

go read them, iykyk 👀

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reminder bestie: everything above is exactly the facts from the page, i just put some sparkle on it. the function signature, the args, the three moments (open, close, hangup), the see-also list — all of it, untouched 🧚

and that's a wrap! this adorable lil page lives at ./drivers/mmc/core and it's dated October 2026 — yes, the future, she's ahead of her time 💀✨ bye bestie, slay your kernel work 💖🌷