STRUCT CDNS_UART(9)

💅 struct cdns_uart — device data, bestie

okay so this is the kernel API manual page for struct cdns_uart, and it's literally just the vibe of a UART device's whole personality stored in one struct. no cap. it's giving "everything you need to know about this device, in a C struct" ✨

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✨ NAME ✨

struct cdns_uart — device data 🎀

like… it's the device data. the whole thing. that's the assignment and it ate.

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🌸 SYNOPSIS 🌸

struct cdns_uart {
    struct uart_port        *port;
    struct clk              *uartclk;
    struct clk              *pclk;
    unsigned int            baud;
    struct notifier_block   clk_rate_change_nb;
    u32 quirks;
    bool cts_override;
    struct gpio_desc        *gpiod_rts;
    bool rs485_tx_started;
    struct hrtimer          tx_timer;
    struct reset_control    *rstc;
 };

copy it exactly, character for character, please and thank you 🫶 this is not the place to freestyle.

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🦋 Members 🦋

okay bestie, field-by-field tour, let's go 💅

• port — pointer to the UART port. iconic. the main character of the struct fr fr.
• uartclk — the reference clock. the clock the whole thing looks up to 🌈
• pclk — the APB clock. second clock, equally valid, we stan both ⭐
• baud — the current baud rate. it's an unsigned int, it's the number, it's the speed, periodt.
• clk_rate_change_nb — notifier block for clock changes. it's literally the "hey bestie, the clock changed" messenger 🔥
• quirks — flags for RXBS support. yes it's spelled "quirks". no we're not changing it. it's quirky like that 🙈
• cts_override — modem control state override. a bool. it overrides. that's the whole job.
• gpiod_rts — pointer to the gpio descriptor. a whole struct gpio_desc *, living its best life 💖
• rs485_tx_started — RS485 tx state. also a bool, also keeping track of whether tx has started, as one does.
• tx_timer — timer for tx. a struct hrtimer, because tx needs its own little clock moment ⏰
• rstc — pointer to the reset control. holding the reset destiny of the whole device 😭

no field left behind. every single one is on the list. we don't skip members in this house 🧚

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👑 SEE ALSO 👑

the kernel file is ./drivers/tty/serial/xilinx_uartps.c — remember that, it's the home base 🏠

and now, the entire friend group, in order, no one gets cut from the group chat:

• cdns_uart_handle_rx(9)
• cdns_rts_gpio_enable(9)
• cdns_rs485_tx_setup(9)
• cdns_rs485_rx_setup(9)
• cdns_uart_tx_empty(9)
• cdns_rs485_rx_callback(9)
• cdns_calc_after_tx_delay(9)
• cdns_uart_handle_tx(9)
• cdns_uart_isr(9)
• cdns_uart_calc_baud_divs(9)
• cdns_uart_set_baud_rate(9)
• cdns_uart_clk_notifier_cb(9)
• cdns_rs485_tx_callback(9)
• cdns_uart_start_tx(9)
• cdns_uart_stop_tx(9)
• cdns_uart_stop_rx(9)
• cdns_uart_break_ctl(9)
• cdns_uart_set_termios(9)
• cdns_uart_startup(9)
• cdns_uart_shutdown(9)
• cdns_uart_type(9)
• cdns_uart_verify_port(9)
• cdns_uart_request_port(9)
• cdns_uart_release_port(9)
• cdns_uart_config_port(9)
• cdns_uart_get_mctrl(9)
• cdns_uart_console_putchar(9)
• cdns_uart_console_write(9)
• cdns_uart_console_setup(9)
• cdns_uart_suspend(9)
• cdns_uart_resume(9)
• cdns_rs485_config(9)
• cdns_uart_probe(9)
• cdns_uart_remove(9)

thirty-four references, all accounted for, and honestly? reading them all is the vibe check you need before touching this driver 💀✨

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lowkey important: this page is part of the Kernel API Manual, from the ./drivers/tty/serial section, dated October 2026, and it's titled struct cdns_uart(9). that's the lore. 💜

anyway bestie that's the whole page — device data, every member named, every function referenced, nothing dropped. slay, go read the source, mwah 🍓💖