Re: [PATCH 1/1] pps: clients: gpio: Bypass edge's direction check when not needed

[Bastien Curutchet]

Hi Rodolfo

> > > diff --git a/drivers/pps/clients/pps-gpio.c 
> > > b/drivers/pps/clients/pps-gpio.c
> > > index 2f4b11b4dfcd..f05fb15ed7f4 100644
> > > --- a/drivers/pps/clients/pps-gpio.c
> > > +++ b/drivers/pps/clients/pps-gpio.c
> > > @@ -52,7 +52,9 @@ static irqreturn_t pps_gpio_irq_handler(int irq, 
> > > void *data)
> > >
> > >          info = data;
> > >
> > > -       rising_edge = gpiod_get_value(info->gpio_pin);
> > > +       rising_edge = info->capture_clear ? \
> > > +                       gpiod_get_value(info->gpio_pin) : \
> > > +                       !info->assert_falling_edge;
> > >          if ((rising_edge && !info->assert_falling_edge) ||
> > >                          (!rising_edge && info->assert_falling_edge))
> > >                  pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data);
> > >
> > > Please, review and test it before resubmitting. :)
> >
> > I'll try this and send a V2 after my tests, thank you.
>
> OK, thanks.
>
> However we should think very well about this modification since it could 
> be the case where we have a device sending both assert and clear events 
> but we wish to catch just the asserts... in this case we will get 
> doubled asserts!

My understanding is that clear events are to be captured only when this
capture_clear boolean is set. If it is not set, the PPS_CAPTURECLEAR
flag is not added to pps_source_info->mode and get_irqf_trigger_flags()
will return only one edge flag (rising or falling depending on
assert-falling-edge DT property).

By the way, I see that the capture_clear is never set since the legacy
platform data support has been dropped (commit ee89646619ba).


Best regards,
Bastien