Re: [PATCH] serial: sa1100: add note about modem control signals

[Russell King - ARM Linux admin <linux@armlinux.org.uk>]

On Fri, May 31, 2019 at 05:31:35PM +0200, Uwe Kleine-König wrote:
> Hello Russell,
> 
> On Fri, May 31, 2019 at 04:24:04PM +0100, Russell King wrote:
> > As suggested by Uwe, add a note indicating that the modem control
> > signals do not support interrupts, which precludes the driver from
> > using mctrl_gpio_init().
> > 
> > Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> > Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
> > ---
> > 
> > Uwe, something like this?
> > 
> >  drivers/tty/serial/sa1100.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
> > index a6b4309b62fc..d7dbf0576be8 100644
> > --- a/drivers/tty/serial/sa1100.c
> > +++ b/drivers/tty/serial/sa1100.c
> > @@ -949,6 +949,9 @@ static int sa1100_serial_resume(struct platform_device *dev)
> >  static int sa1100_serial_add_one_port(struct sa1100_port *sport, struct platform_device *dev)
> >  {
> >  	sport->port.dev = &dev->dev;
> > +
> > +	// GPIO driver does not support interrupts for these modem
> > +	// control signals, so the serial driver polls them.
> >  	sport->gpios = mctrl_gpio_init_noauto(sport->port.dev, 0);
> >  	if (IS_ERR(sport->gpios)) {
> >  		int err = PTR_ERR(sport->gpios);
> 
> I would mention that because of this mctrl_gpio_init cannot be used.

Ok.

> (And I would have expected C-like comments).

It seems that Linus has changed his opinion on C99 commenting style,
from "it's not real C" to "I prefer it":

https://lore.kernel.org/patchwork/patch/852060/

Yes, this is mostly about the SPDX commenting style, but Linus seems to
be expressing a general preference towards "//" style comments over
"/* */" comments, especially for new comments.

Specifically see replies #14 and #18, especially #18 where the
discussion moves towards trailing-line comments for structure members.

-- 
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