redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

serdev: add helpers for cts and rts handling 

Add serdev helper functions for handling of cts and rts
lines using the serdev's tiocm functions.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
hifive-unleashed-5.1
Sebastian Reichel 2017-03-28 17:59:33 +02:00 committed by Marcel Holtmann
parent 5659dab26f
commit 756db77874
1 changed files with 31 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
include/linux/serdev.h
View File

@ -16,6 +16,7 @@
#include <linux/types.h>
#include <linux/device.h>
#include <linux/termios.h>
#include <linux/delay.h>
struct serdev_controller;
struct serdev_device;
@ -254,6 +255,36 @@ static inline int serdev_device_write_room(struct serdev_device *sdev)
#endif /* CONFIG_SERIAL_DEV_BUS */
static inline bool serdev_device_get_cts(struct serdev_device *serdev)
{
int status = serdev_device_get_tiocm(serdev);
return !!(status & TIOCM_CTS);
}
static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
{
unsigned long timeout;
bool signal;
timeout = jiffies + msecs_to_jiffies(timeout_ms);
while (time_is_after_jiffies(timeout)) {
signal = serdev_device_get_cts(serdev);
if (signal == state)
return 0;
usleep_range(1000, 2000);
}
return -ETIMEDOUT;
}
static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
{
if (enable)
return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
else
return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
}
/*
* serdev hooks into TTY core
*/