Commit 9d31746b authored by John Ogness's avatar John Ogness Committed by Greg Kroah-Hartman
Browse files

serial: 8250: Do not set UART_LSR_THRE in @read_status_mask 



Since Linux 2.1.8 @read_status_mask is no longer used as a
general control of which bits are used from the LSR register.
Instead it has become an additional mask applied to
@ignore_status_mask. Since UART_LSR_THRE is never set for
@ignore_status_mask, it serves no purpose to set it for
@read_status_mask. In fact, it propagates the misconception
that @read_status_mask can be used as a general mask for LSR
bits.

Do not set UART_LSR_THRE for @read_status_mask.

Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20241216171244.12783-3-john.ogness@linutronix.de


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c9f49e3e

drivers/tty/serial/8250/8250_omap.c

+1 −1
Original line number Diff line number Diff line
@@ -412,7 +412,7 @@ static void omap_8250_set_termios(struct uart_port *port, 
	 */

	uart_update_timeout(port, termios->c_cflag, baud);



	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;

	up->port.read_status_mask = UART_LSR_OE | UART_LSR_DR;

	if (termios->c_iflag & INPCK)

		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;

	if (termios->c_iflag & (IGNBRK | PARMRK))

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

+1 −1
Original line number Diff line number Diff line
@@ -2786,7 +2786,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, 
	 */

	uart_update_timeout(port, termios->c_cflag, baud);



	port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;

	port->read_status_mask = UART_LSR_OE | UART_LSR_DR;

	if (termios->c_iflag & INPCK)

		port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;

	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))