On Thu, Mar 30, 2017 at 5:00 PM, Andrey Smirnov <andrew.smirnov@xxxxxxxxx> wrote: > Add serdev_device_write() a blocking call allowing to transfer > arbitraty amount of data (potentially exceeding amount that > serdev_device_write_buf can process in a single call) > > To support that, also add serdev_device_write_wakeup(). > > Drivers wanting to use full extent of serdev_device_write > functionality are expected to provide serdev_device_write_wakeup() as > a sole handler of .write_wakeup event or call it as a part of driver's > custom .write_wakeup code. > > Because serdev_device_write() subroutine is a superset of > serdev_device_write_buf() the patch re-impelements latter is terms of > the former. For drivers watning to just use serdev_device_write_buf() typo > .write_wakeup handler is optional. > > Cc: cphealy@xxxxxxxxx > Cc: Guenter Roeck <linux@xxxxxxxxxxxx> > Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > Cc: linux-serial@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx> > --- > > Changes since v2 (see [v2]): > > - Changed subject and commit message wording to better reflect > nature of the patch > > - Various spelling, formatting, documentation and wording > fixes as caught/suggested by Andy > > Changes since v1 (see [v1]): > > - Make timeout to be a total(as opposed to per-iteration) > timeout > > - Keep serdev_device_write_buf() as a wrapper arount > serdev_device_write() for compatibility > > [v2] https://lkml.org/lkml/2017/3/28/942 > [v1] https://lkml.org/lkml/2017/3/20/650 > > drivers/tty/serdev/core.c | 36 +++++++++++++++++++++++++++++++----- > include/linux/serdev.h | 17 +++++++++++++++-- > 2 files changed, 46 insertions(+), 7 deletions(-) > > diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c > index f4c6c90..6701d10 100644 > --- a/drivers/tty/serdev/core.c > +++ b/drivers/tty/serdev/core.c > @@ -116,17 +116,41 @@ void serdev_device_close(struct serdev_device *serdev) > } > EXPORT_SYMBOL_GPL(serdev_device_close); > > -int serdev_device_write_buf(struct serdev_device *serdev, > - const unsigned char *buf, size_t count) > +void serdev_device_write_wakeup(struct serdev_device *serdev) > +{ > + complete(&serdev->write_comp); > +} > +EXPORT_SYMBOL_GPL(serdev_device_write_wakeup); > + > +int serdev_device_write(struct serdev_device *serdev, > + const unsigned char *buf, size_t count, > + unsigned long timeout) > { > struct serdev_controller *ctrl = serdev->ctrl; > + int ret; > > - if (!ctrl || !ctrl->ops->write_buf) > + if (!ctrl || !ctrl->ops->write_buf || > + (timeout && !serdev->ops->write_wakeup)) > return -EINVAL; > > - return ctrl->ops->write_buf(ctrl, buf, count); > + mutex_lock(&serdev->write_lock); > + do { > + reinit_completion(&serdev->write_comp); > + > + ret = ctrl->ops->write_buf(ctrl, buf, count); > + if (ret < 0) > + break; > + > + buf += ret; > + count -= ret; > + > + } while (count && > + (timeout = wait_for_completion_timeout(&serdev->write_comp, > + timeout))); Need to test for timeout < 0 here and return timeout when < 0. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
