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

[Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>]

pon., 4 lis 2019 o 16:59 Kent Gibson <warthog618@xxxxxxxxx> napisał(a):
>
> On Mon, Nov 04, 2019 at 04:50:30PM +0100, Bartosz Golaszewski wrote:
> > pon., 4 lis 2019 o 16:39 Kent Gibson <warthog618@xxxxxxxxx> 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@xxxxxxxxx>
> > > ---
> > >  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.
>
>

No problem, it can wait until tomorrow. Please use the following
branch - gpio/for-kent - from my tree.

Bart