diff options
| author | Johan Hovold <johan@kernel.org> | 2018-11-14 16:09:03 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-11-27 19:44:21 +0100 |
| commit | 70d188041e6f1f92004f1d5d7ddfd5013273b7a5 (patch) | |
| tree | a5352d3efbcdbe1bb3b152f204907e308f620b21 | |
| parent | 0bbf0a88fa29de6a043ba40058409c7e550fc8be (diff) | |
serdev: make synchronous write helper interruptible
Allow the synchronous serdev_device_write() helper to be interrupted.
This is useful for cases where I/O is performed on behalf of user space
and we don't want to block indefinitely when using flow control.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serdev/core.c | 20 | ||||
| -rw-r--r-- | include/linux/serdev.h | 2 |
2 files changed, 15 insertions, 7 deletions
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c index ee4c40336633..c7006bbb793a 100644 --- a/drivers/tty/serdev/core.c +++ b/drivers/tty/serdev/core.c @@ -231,7 +231,7 @@ EXPORT_SYMBOL_GPL(serdev_device_write_buf); int serdev_device_write(struct serdev_device *serdev, const unsigned char *buf, size_t count, - unsigned long timeout) + long timeout) { struct serdev_controller *ctrl = serdev->ctrl; int written = 0; @@ -254,16 +254,24 @@ int serdev_device_write(struct serdev_device *serdev, written += ret; buf += ret; count -= ret; - } while (count && - (timeout = wait_for_completion_timeout(&serdev->write_comp, - timeout))); + + if (count == 0) + break; + + timeout = wait_for_completion_interruptible_timeout(&serdev->write_comp, + timeout); + } while (timeout > 0); mutex_unlock(&serdev->write_lock); if (ret < 0) return ret; - if (timeout == 0 && written == 0) - return -ETIMEDOUT; + if (timeout <= 0 && written == 0) { + if (timeout == -ERESTARTSYS) + return -ERESTARTSYS; + else + return -ETIMEDOUT; + } return written; } diff --git a/include/linux/serdev.h b/include/linux/serdev.h index f153b2c7f0cd..070bf4e92df7 100644 --- a/include/linux/serdev.h +++ b/include/linux/serdev.h @@ -210,7 +210,7 @@ void serdev_device_wait_until_sent(struct serdev_device *, long); int serdev_device_get_tiocm(struct serdev_device *); int serdev_device_set_tiocm(struct serdev_device *, int, int); void serdev_device_write_wakeup(struct serdev_device *); -int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, unsigned long); +int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, long); void serdev_device_write_flush(struct serdev_device *); int serdev_device_write_room(struct serdev_device *); |