Re: [PATCH 3/4] tty/serdev: add serdev registration interface

[Johan Hovold <johan@kernel.org>]

On Thu, May 18, 2017 at 04:43:42PM +0200, Greg Kroah-Hartman wrote:
> On Tue, Apr 11, 2017 at 07:07:30PM +0200, Johan Hovold wrote:
> > Add a new interface for registering a serdev controller and clients, and
> > a helper function to deregister serdev devices (or a tty device) that
> > were previously registered using the new interface.
> > 
> > Once every driver currently using the tty_port_register_device() helpers
> > have been vetted and converted to use the new serdev registration
> > interface (at least for deregistration), we can move serdev registration
> > to the current helpers and get rid of the serdev-specific functions.
> > 
> > Signed-off-by: Johan Hovold <johan@kernel.org>
> > Reviewed-by: Rob Herring <robh@kernel.org>
> > ---
> >  drivers/tty/serdev/serdev-ttyport.c |  6 ++-
> >  drivers/tty/tty_port.c              | 76 +++++++++++++++++++++++++++++++++++++
> >  include/linux/serdev.h              |  7 +++-
> >  include/linux/tty.h                 |  9 +++++
> >  4 files changed, 94 insertions(+), 4 deletions(-)
> 
> This patch doesn't apply

Probably because it was generated against v4.11-rc which did not have
the write_buf wrapper which you just reverted (after which the patch
seems to apply just fine again).

I'll submit a rebased v2 of the two remaining patches anyway.

> and should it really be a 4.12-final patch?

I think so. serdev was enabled in 4.11 by hooking into the tty layer at
the wrong place, which is what this series addresses. I had hoped to get
at least the revert-patch into 4.11-final, and the rest into 4.12, to
avoid disabling something which had once been enabled.

The remaining two patches only re-enables serdev for a subset of tty
drivers (for which it is safe to do so) by using the new tty-port
registration functions in serial-core only.

In effect we'd up with serdev disabled in 4.11 and enabled for
serial-core in 4.12 (which is the first release that has driver using
serdev).

Does that make sense?

Thanks,
Johan