[PATCH 3/5] tty: serial: 8250 core: allow to set ->throttle / ->unthrottle callbacks
From: bigeasy@linutronix.de (Sebastian Andrzej Siewior)
Date: 2014-07-16 14:46:22
Also in:
linux-omap, linux-serial, lkml
Subsystem:
8250/16?50 (and clone uarts) serial driver, the rest, tty layer and serial drivers · Maintainers:
Greg Kroah-Hartman, Linus Torvalds, Jiri Slaby
The omap uart provides support for HW assisted flow control. What is missing is the support to throttle / unthrottle callbacks which are used by the omap-serial driver at the moment. This patch adds the callbacks. It should be safe to add them since they are only invovked from the serial_core (uart_throttle()) if the feature flags are set. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- drivers/tty/serial/8250/8250_core.c | 14 ++++++++++++++ include/linux/serial_core.h | 2 ++ 2 files changed, 16 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index bd0e1897..714f954 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c@@ -1320,6 +1320,16 @@ static void serial8250_start_tx(struct uart_port *port) } } +static void serial8250_throttle(struct uart_port *port) +{ + port->throttle(port); +} + +static void serial8250_unthrottle(struct uart_port *port) +{ + port->unthrottle(port); +} + static void serial8250_stop_rx(struct uart_port *port) { struct uart_8250_port *up =
@@ -2752,6 +2762,8 @@ static struct uart_ops serial8250_pops = { .get_mctrl = serial8250_get_mctrl, .stop_tx = serial8250_stop_tx, .start_tx = serial8250_start_tx, + .throttle = serial8250_throttle, + .unthrottle = serial8250_unthrottle, .stop_rx = serial8250_stop_rx, .enable_ms = serial8250_enable_ms, .break_ctl = serial8250_break_ctl,
@@ -3300,6 +3312,8 @@ int serial8250_register_8250_port(struct uart_8250_port *up) uart->port.fifosize = up->port.fifosize; uart->tx_loadsz = up->tx_loadsz; uart->capabilities = up->capabilities; + uart->port.throttle = up->port.throttle; + uart->port.unthrottle = up->port.unthrottle; /* Take tx_loadsz from fifosize if it wasn't set separately */ if (uart->port.fifosize && !uart->tx_loadsz)
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 6f20ff0..c380af2 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h@@ -124,6 +124,8 @@ struct uart_port { struct ktermios *old); int (*startup)(struct uart_port *port); void (*shutdown)(struct uart_port *port); + void (*throttle)(struct uart_port *port); + void (*unthrottle)(struct uart_port *port); int (*handle_irq)(struct uart_port *); void (*pm)(struct uart_port *, unsigned int state, unsigned int old);
--
2.0.1