From: John Ogness Date: Mon, 16 Dec 2024 17:12:44 +0000 (+0106) Subject: serial: 8250: Explain the role of @read_status_mask X-Git-Tag: v6.14-rc1~59^2~27 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b3ee0bc1a065469cfbcef0c35dc42f138563a1fb;p=thirdparty%2Fkernel%2Flinux.git serial: 8250: Explain the role of @read_status_mask The role of @read_status_mask has changed over time and seems to still cause confusion. This can be expected since there is zero documentation about this driver-specific variable. Add comments to the initialization of @read_status_mask to clarify its role. Signed-off-by: John Ogness Link: https://lore.kernel.org/r/20241216171244.12783-5-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 10144fcc0363c..42b4aa56b9020 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -412,6 +412,12 @@ static void omap_8250_set_termios(struct uart_port *port, */ uart_update_timeout(port, termios->c_cflag, baud); + /* + * Specify which conditions may be considered for error + * handling and the ignoring of characters. The actual + * ignoring of characters only occurs if the bit is set + * in @ignore_status_mask as well. + */ 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; diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 3b9dc2bb06ebe..1a65d3e5f3c03 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2785,6 +2785,12 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, */ uart_update_timeout(port, termios->c_cflag, baud); + /* + * Specify which conditions may be considered for error + * handling and the ignoring of characters. The actual + * ignoring of characters only occurs if the bit is set + * in @ignore_status_mask as well. + */ 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;