Re: [PATCH v2 3/3] serial: core: Update uart_poll_timeout() function to return unsigned long

From: VAMSHI GAJJELA
Date: Thu Oct 26 2023 - 08:29:04 EST


On Thu, Oct 26, 2023 at 2:54 PM Ilpo Järvinen
<ilpo.jarvinen@xxxxxxxxxxxxxxx> wrote:
>
> On Thu, 26 Oct 2023, Jiri Slaby wrote:
>
> > On 25. 10. 23, 16:26, Vamshi Gajjela wrote:
> > > From: VAMSHI GAJJELA <vamshigajjela@xxxxxxxxxx>
> > >
> > > The function uart_fifo_timeout() returns an unsigned long value, which is
> > > the number of jiffies. Therefore, the function uart_poll_timeout() has been
> > > modified to use an unsigned long type for timeout values instead of an int
> > > and to avoid truncation.
> >
> > Hi,
> >
> > there is no truncation possible, right?
>
> That's very likely true (I didn't run the calculations), thus it's correct
> to not have Fixes tag. It's more about having consistent typing since
> we're talking about jiffies, so unsigned long as usual.
>
> > > The return type of the function uart_poll_timeout() has also been changed
> > > from int to unsigned long to be consistent with the type of timeout values.
>
> Don't write changes you make in the patch in the past tense. Just say:
>
> Change the return type of uart_poll_timeout() from ...
>
> The comment also applies to the other sentence above this one.
Sure, will update commit message.
>
> --
> i.
>
> > > Signed-off-by: VAMSHI GAJJELA <vamshigajjela@xxxxxxxxxx>
> > > ---
> > > v2:
> > > - unsigned long instead of unsigned int
> > > - added () after function name in short log
> > > - updated description
> > > include/linux/serial_core.h | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
> > > index bb6f073bc159..6916a1d7e477 100644
> > > --- a/include/linux/serial_core.h
> > > +++ b/include/linux/serial_core.h
> > > @@ -773,9 +773,9 @@ static inline unsigned long uart_fifo_timeout(struct
> > > uart_port *port)
> > > }
> > > /* Base timer interval for polling */
> > > -static inline int uart_poll_timeout(struct uart_port *port)
> > > +static inline unsigned long uart_poll_timeout(struct uart_port *port)
> > > {
> > > - int timeout = uart_fifo_timeout(port);
> > > + unsigned long timeout = uart_fifo_timeout(port);
> > > return timeout > 6 ? (timeout / 2 - 2) : 1;
> > > }
> >
> >