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Commit c5f78b1f authored by Jeremy Kerr's avatar Jeremy Kerr Committed by Greg Kroah-Hartman
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serial: Introduce UPSTAT_SYNC_FIFO for synchronised FIFOs 



This change adds a flag to indicate that a UART is has an external means
of synchronising its FIFO, without needing CTSRTS or XON/XOFF.

This allows us to use the throttle/unthrottle callbacks, without having
to claim other methods of flow control.

Signed-off-by: default avatarJeremy Kerr <jk@ozlabs.org>
Tested-by: default avatarEddie James <eajames@linux.vnet.ibm.com>
Tested-by: default avatarJoel Stanley <joel@jms.id.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d6810a82

drivers/tty/serial/serial_core.c

+2 −2
Original line number Diff line number Diff line
@@ -674,8 +674,8 @@ static void uart_send_xchar(struct tty_struct *tty, char ch) 
static void uart_throttle(struct tty_struct *tty)

{

	struct uart_state *state = tty->driver_data;

	upstat_t mask = UPSTAT_SYNC_FIFO;

	struct uart_port *port;

	upstat_t mask = 0;



	port = uart_port_ref(state);

	if (!port)
@@ -703,8 +703,8 @@ static void uart_throttle(struct tty_struct *tty) 
static void uart_unthrottle(struct tty_struct *tty)

{

	struct uart_state *state = tty->driver_data;

	upstat_t mask = UPSTAT_SYNC_FIFO;

	struct uart_port *port;

	upstat_t mask = 0;



	port = uart_port_ref(state);

	if (!port)

include/linux/serial_core.h

+1 −0
Original line number Diff line number Diff line
@@ -233,6 +233,7 @@ struct uart_port { 
#define UPSTAT_AUTORTS		((__force upstat_t) (1 << 2))

#define UPSTAT_AUTOCTS		((__force upstat_t) (1 << 3))

#define UPSTAT_AUTOXOFF		((__force upstat_t) (1 << 4))

#define UPSTAT_SYNC_FIFO	((__force upstat_t) (1 << 5))



	int			hw_stopped;		/* sw-assisted CTS flow state */

	unsigned int		mctrl;			/* current modem ctrl settings */