diff options
| author | Jeremy Kerr <jk@ozlabs.org> | 2018-03-27 11:48:24 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-23 10:16:50 +0200 |
| commit | c5f78b1fe4e5baf4c4ca30377c2d7e06e2e391ec (patch) | |
| tree | 7aa24241fd71460d638053895d3585660e10881e | |
| parent | d6810a82c7c7e3b262db5e9e67f6bd81b41f3840 (diff) | |
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: Jeremy Kerr <jk@ozlabs.org>
Tested-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 4 | ||||
| -rw-r--r-- | include/linux/serial_core.h | 1 |
2 files changed, 3 insertions, 2 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 0466f9f08a91..c47158c93202 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -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) diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 1d356105f25a..d224961e1346 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -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 */ |