diff options
| author | Sebastian Reichel <sre@kernel.org> | 2017-03-28 17:59:33 +0200 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2017-04-12 22:12:17 +0200 |
| commit | 756db778748949f6403b727fc6251674dbfcb1a2 (patch) | |
| tree | 2ffc37d520851de2f60a46d9e169e7714ef09958 | |
| parent | 5659dab26f09a60db8bd1600e1ce89802fab1c7f (diff) | |
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>
| -rw-r--r-- | include/linux/serdev.h | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/serdev.h b/include/linux/serdev.h index e29a270f603c..37395b8eb8f1 100644 --- a/include/linux/serdev.h +++ b/include/linux/serdev.h @@ -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 */ |