Re: [PATCH 0/4] serdev: make serdev_device_write() more usable

From: Rob Herring
Date: Mon Nov 19 2018 - 10:16:52 EST


On Wed, Nov 14, 2018 at 9:10 AM Johan Hovold <johan@xxxxxxxxxx> wrote:
>
> This series make the synchronous serdev_device_write() helper more
> usable by
>
> 1) allowing drivers to pass a zero timeout to indicate that they
> want to wait forever;
>
> 2) returning the number of bytes actually written (buffered)
> if the helper is interrupted;
>
> 3) make the helper use interruptible wait so that the helper can
> be used on behalf of user space.
>
> Finally, the two write functions are documented using kernel-doc.
>
> Turns out I was using the wrong timeout for two gnss drivers that
> expected the helper to wait indefinitely. I've fixed up those separately
> (by using MAX_SCHEDULE_TIMEOUT for now), but for the helper to be usable
> when using flow control we really want it to be interruptible.
>
> Besides the two gnss drivers, there's currently only one other in-kernel
> user of this helper and that driver (rave-sp) uses a non-zero timeout
> and doesn't check the return value and therefore does not need to be
> updated.
>
> Note that this series depends on the two above mentioned GNSS fixes
> (submitted for v4.20-rc3).
>
> Johan
>
>
> Johan Hovold (4):
> serdev: use zero to indicate infinite write timeout
> serdev: make synchronous write return bytes written
> serdev: make synchronous write helper interruptible
> serdev: document the write functions using kernel-doc

Other than the one nit, for the series:

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>