Commit cdc4a3e0 authored by Jiri Slaby (SUSE)'s avatar Jiri Slaby (SUSE) Committed by Greg Kroah-Hartman
Browse files

serial: 8250: extract serial8250_set_fcr() 



serial8250_do_set_termios() consists of many registers and up flags
settings. Extract all these into separate functions. This time, setting
of FCR.

serial8250_do_set_termios() looks sane at this point.

Signed-off-by: default avatar"Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20250611100319.186924-25-jirislaby@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c5d43d65

drivers/tty/serial/8250/8250_port.c

+26 −15
Original line number Diff line number Diff line
@@ -2792,6 +2792,30 @@ static void serial8250_set_efr(struct uart_port *port, struct ktermios *termios) 
	serial_port_out(port, efr_reg, efr);

}



static void serial8250_set_fcr(struct uart_port *port, struct ktermios *termios)

{

	struct uart_8250_port *up = up_to_u8250p(port);

	bool is_16750 = port->type == PORT_16750;



	if (is_16750)

		serial_port_out(port, UART_FCR, up->fcr);



	/*

	 * LCR DLAB must be reset to enable 64-byte FIFO mode. If the FCR is written without DLAB

	 * set, this mode will be disabled.

	 */

	serial_port_out(port, UART_LCR, up->lcr);



	if (is_16750)

		return;



	/* emulated UARTs (Lucent Venus 167x) need two steps */

	if (up->fcr & UART_FCR_ENABLE_FIFO)

		serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);



	serial_port_out(port, UART_FCR, up->fcr);

}



void

serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,

		          const struct ktermios *old)
@@ -2823,22 +2847,9 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, 
	serial8250_set_ier(port, termios);

	serial8250_set_efr(port, termios);

	serial8250_set_divisor(port, baud, quot, frac);



	/*

	 * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR

	 * is written without DLAB set, this mode will be disabled.

	 */

	if (port->type == PORT_16750)

		serial_port_out(port, UART_FCR, up->fcr);



	serial_port_out(port, UART_LCR, up->lcr);	/* reset DLAB */

	if (port->type != PORT_16750) {

		/* emulated UARTs (Lucent Venus 167x) need two steps */

		if (up->fcr & UART_FCR_ENABLE_FIFO)

			serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);

		serial_port_out(port, UART_FCR, up->fcr);	/* set fcr */

	}

	serial8250_set_fcr(port, termios);

	serial8250_set_mctrl(port, port->mctrl);



	uart_port_unlock_irqrestore(port, flags);

	serial8250_rpm_put(up);