serdev: add serdev_device_wait_until_sent

Add method, which waits until the transmission buffer has been sent.
Note, that the change in ttyport_write_wakeup is related, since
tty_wait_until_sent will hang without that change.

Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Sebastian Reichel 2017-03-28 17:59:31 +02:00 committed by Marcel Holtmann
parent 2f09276769
commit b3f80c8f75
3 changed files with 28 additions and 4 deletions

View file

@ -173,6 +173,17 @@ void serdev_device_set_flow_control(struct serdev_device *serdev, bool enable)
}
EXPORT_SYMBOL_GPL(serdev_device_set_flow_control);
void serdev_device_wait_until_sent(struct serdev_device *serdev, long timeout)
{
struct serdev_controller *ctrl = serdev->ctrl;
if (!ctrl || !ctrl->ops->wait_until_sent)
return;
ctrl->ops->wait_until_sent(ctrl, timeout);
}
EXPORT_SYMBOL_GPL(serdev_device_wait_until_sent);
static int serdev_drv_probe(struct device *dev)
{
const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);

View file

@ -14,6 +14,7 @@
#include <linux/serdev.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/poll.h>
#define SERPORT_ACTIVE 1
@ -46,11 +47,11 @@ static void ttyport_write_wakeup(struct tty_port *port)
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
if (!test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &port->tty->flags))
return;
if (test_bit(SERPORT_ACTIVE, &serport->flags))
if (test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &port->tty->flags) &&
test_bit(SERPORT_ACTIVE, &serport->flags))
serdev_controller_write_wakeup(ctrl);
wake_up_interruptible_poll(&port->tty->write_wait, POLLOUT);
}
static const struct tty_port_client_operations client_ops = {
@ -167,6 +168,14 @@ static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable
tty_set_termios(tty, &ktermios);
}
static void ttyport_wait_until_sent(struct serdev_controller *ctrl, long timeout)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
tty_wait_until_sent(tty, timeout);
}
static const struct serdev_controller_ops ctrl_ops = {
.write_buf = ttyport_write_buf,
.write_flush = ttyport_write_flush,
@ -175,6 +184,7 @@ static const struct serdev_controller_ops ctrl_ops = {
.close = ttyport_close,
.set_flow_control = ttyport_set_flow_control,
.set_baudrate = ttyport_set_baudrate,
.wait_until_sent = ttyport_wait_until_sent,
};
struct device *serdev_tty_port_register(struct tty_port *port,

View file

@ -81,6 +81,7 @@ struct serdev_controller_ops {
void (*close)(struct serdev_controller *);
void (*set_flow_control)(struct serdev_controller *, bool);
unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
void (*wait_until_sent)(struct serdev_controller *, long);
};
/**
@ -186,6 +187,7 @@ int serdev_device_open(struct serdev_device *);
void serdev_device_close(struct serdev_device *);
unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
void serdev_device_set_flow_control(struct serdev_device *, bool);
void serdev_device_wait_until_sent(struct serdev_device *, long);
int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
void serdev_device_write_flush(struct serdev_device *);
int serdev_device_write_room(struct serdev_device *);
@ -223,6 +225,7 @@ static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev
return 0;
}
static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
static inline int serdev_device_write_buf(struct serdev_device *sdev, const unsigned char *buf, size_t count)
{
return -ENODEV;