Re: [PATCH 1/3] drm/bridge: it6505: Modified power sequence

[Chen-Yu Tsai]

On Tue, Jul 12, 2022 at 4:08 PM Robert Foss <robert.foss@xxxxxxxxxx> wrote:
>
> Hi Allen,
>
> On Thu, 7 Jul 2022 at 10:06, allen <allen.chen@xxxxxxxxxx> wrote:
> >
> > From: allen chen <allen.chen@xxxxxxxxxx>
> >
> > Change power sequence to meet it6505 data sheet requirement when boot on.
> >
> > Signed-off-by: Pin-Yen Lin <treapking@xxxxxxxxxxxx>
> > Signed-off-by: Allen Chen <allen.chen@xxxxxxxxxx>
> >
> > ---
> >  drivers/gpu/drm/bridge/ite-it6505.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> > index 2d119e3016b3..aa5e0aa1af85 100644
> > --- a/drivers/gpu/drm/bridge/ite-it6505.c
> > +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> > @@ -3029,7 +3029,7 @@ static int it6505_init_pdata(struct it6505 *it6505)
> >                 return PTR_ERR(pdata->ovdd);
> >         }
> >
> > -       pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
> > +       pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
>
> Making this change is problematic since it requires a corresponding
> change in all of the device trees that use this device. It's against
> policy to change this interface after it has been introduced.
>
> Unless anyone thinks otherwise, I would like to see this patch dropped.

I think you're confusing GPIO_ACTIVE_{LOW,HIGH} flags in the device tree
vs GPIOD_OUT_{LOW,HIGH}, which just sets the "default" state the GPIO
should be in when it is requested.

This change doesn't impact the device tree.


Regards
ChenYu

> >         if (IS_ERR(pdata->gpiod_reset)) {
> >                 dev_err(dev, "gpiod_reset gpio not found");
> >                 return PTR_ERR(pdata->gpiod_reset);
> > --
> > 2.25.1
> >