From 0bbf0a88fa29de6a043ba40058409c7e550fc8be Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 14 Nov 2018 16:09:02 +0100 Subject: serdev: make synchronous write return bytes written Make the synchronous serdev_device_write() helper behave analogous to the asynchronous serdev_device_write_buf() by returning the number of bytes written (or rather buffered) also on timeout. This will allow drivers to distinguish the case where data was partially written from the case where no data was written. Also update the only two users that checked the return value. Signed-off-by: Johan Hovold Reviewed-by: Rob Herring Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serdev/core.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c index c7d637d2bc56..ee4c40336633 100644 --- a/drivers/tty/serdev/core.c +++ b/drivers/tty/serdev/core.c @@ -234,6 +234,7 @@ int serdev_device_write(struct serdev_device *serdev, unsigned long timeout) { struct serdev_controller *ctrl = serdev->ctrl; + int written = 0; int ret; if (!ctrl || !ctrl->ops->write_buf || !serdev->ops->write_wakeup) @@ -250,14 +251,21 @@ int serdev_device_write(struct serdev_device *serdev, if (ret < 0) break; + written += ret; buf += ret; count -= ret; - } while (count && (timeout = wait_for_completion_timeout(&serdev->write_comp, timeout))); mutex_unlock(&serdev->write_lock); - return ret < 0 ? ret : (count ? -ETIMEDOUT : 0); + + if (ret < 0) + return ret; + + if (timeout == 0 && written == 0) + return -ETIMEDOUT; + + return written; } EXPORT_SYMBOL_GPL(serdev_device_write); -- cgit v1.2.3