On Fri, Mar 15, 2013 at 07:03:08AM -0400, Peter Hurley wrote:
> On Fri, 2013-03-15 at 10:24 +0100, Johan Hovold wrote:
> > On Wed, Mar 13, 2013 at 03:43:43PM -0400, Peter Hurley wrote:
> > > On Thu, 2013-03-07 at 15:55 +0100, Johan Hovold wrote:
> > > > Make sure to check ASYNC_INITIALISED before raising DTR when waking up
> > > > from blocked open in tty_port_block_til_ready.
> > > >
> > > > Currently DTR could get raised at hang up as a blocked process would
> > > > raise DTR unconditionally before checking for hang up and returning.
> > > >
> > > > Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx>
> > > > ---
> > > > drivers/tty/tty_port.c | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
> > > > index 3de5918..52f1066 100644
> > > > --- a/drivers/tty/tty_port.c
> > > > +++ b/drivers/tty/tty_port.c
> > > > @@ -355,7 +355,7 @@ int tty_port_block_til_ready(struct tty_port *port,
> > > >
> > > > while (1) {
> > > > /* Indicate we are open */
> > > > - if (tty->termios.c_cflag & CBAUD)
> > > > + if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
> > > > tty_port_raise_dtr_rts(port);
> > > >
> > > > prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE);
> > >
> > > This is ok, but there are 6 other *_block_til_ready() functions:
> ^^^^^^
> Comment on patch
I saw that, but just wanted to stress that those comments shouldn't
block the series.
> > Yes, but that's not really a comment on this patch, is it?
> >
> > The purpose of this series is to fix the tty-port implementation, and
> > I've only touched individual drivers when I had to in order not to break
> > anything due to changed assumptions.
> >
> > There's a ton of buggy and odd behaviour to be found once you start
> > turning the stones. Drivers like the ones below really ought to be
> > using tty ports and it's helpers.
>
> Sure, I understand.
>
> OTOH, tty_port and these drivers stem from the same ancestor and it's
> partly because of localized bug fixes like these that the drivers have
> buggy and odd behavior (because tty_port gets fixed and these do not).
Arguably, fixing the core isn't really a localised bug fix. Some of
those drivers you mentioned have custom open, close, hangup which are
quite different from the tty port implementation, and surely would have
a lot to gain from being ported to tty ports if someone could find the
time to do so.
> As you can verify from the changelogs of these drivers, it's traditional
> to continue to maintain the common aspects, despite the desire to
> abandon them.
Most entries I see have to do with changed interfaces.
> That said, I'm not the maintainer so feel free to disagree with my
> point-of-view.
You do have a point, and I will try to find the time for a follow-up
series fixing at least a few of those five-or-so custom block_til_ready
you pointed to.
Thanks,
Johan
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