Re: [PATCH v5 4/7] gpiolib: add support for biasing output lines

[Kent Gibson <warthog618@gmail.com>]

On Mon, Nov 04, 2019 at 04:50:30PM +0100, Bartosz Golaszewski wrote:
> pon., 4 lis 2019 o 16:39 Kent Gibson <warthog618@gmail.com> napisał(a):
> >
> > Allow pull up/down bias to be set on output lines.
> > Use case is for open source or open drain applications where
> > internal pull up/down may conflict with external biasing.
> >
> > Signed-off-by: Kent Gibson <warthog618@gmail.com>
> > ---
> >  drivers/gpio/gpiolib.c | 8 ++++++--
> >  1 file changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index 7d8ff52ada42..de08d1a4a3fb 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -555,8 +555,9 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
> >              (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
> >                 return -EINVAL;
> >
> > -       /* Bias flags only allowed for input mode. */
> > -       if (!(lflags & GPIOHANDLE_REQUEST_INPUT) &&
> > +       /* Bias flags only allowed for input or output mode. */
> > +       if (!((lflags & GPIOHANDLE_REQUEST_INPUT) ||
> > +             (lflags & GPIOHANDLE_REQUEST_OUTPUT)) &&
> >             ((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
> >              (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
> >              (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
> > @@ -3144,6 +3145,9 @@ int gpiod_direction_output(struct gpio_desc *desc, int value)
> >         }
> >
> >  set_output_value:
> > +       ret = gpio_set_bias(gc, desc);
> > +       if (ret)
> > +               return ret;
> >         return gpiod_direction_output_raw_commit(desc, value);
> 
> Ugh, I missed one thing here - my for-next branch doesn't contain the
> following commit e735244e2cf0 ("gpiolib: don't clear FLAG_IS_OUT when
> emulating open-drain/open-source") which happens to modify this
> function.
> 
> If I provided you with a branch containing it - would it be a lot of
> effort on your part to rebase it on top of it? If so - I can do it
> myself.
> 

I can do a rebase - though not until tomorrow (it is getting late here).
I would like that commit in as well - I suspect it being missing is
the reason a couple of the gpiod tests I was working on are failing.
I was in the process of tracking that down when I switched back to this.

Cheers,
Kent.