Re: [PATCH RESEND 3/4] dt-bindings: drm/bridge: Add GPIO display mux binding

[Rob Herring <robh@kernel.org>]

On Mon, Dec 16, 2019 at 03:16:23PM +0800, Hsin-Yi Wang wrote:
> On Sat, Dec 14, 2019 at 5:29 AM Rob Herring <robh+dt@kernel.org> wrote:
> >
> > On Wed, Dec 11, 2019 at 12:19 AM Hsin-Yi Wang <hsinyi@chromium.org> wrote:
> > >
> > > From: Nicolas Boichat <drinkcat@chromium.org>
> > >
> > > Add bindings for Generic GPIO mux driver.
> > >
> > > Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
> > > Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> > > ---
> > > Change from RFC to v1:
> > > - txt to yaml
> > > ---
> > >  .../bindings/display/bridge/gpio-mux.yaml     | 89 +++++++++++++++++++
> > >  1 file changed, 89 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml
> > > new file mode 100644
> > > index 000000000000..cef098749066
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/display/bridge/gpio-mux.yaml
> > > @@ -0,0 +1,89 @@
> > > +# SPDX-License-Identifier: GPL-2.0
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/display/bridge/gpio-mux.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Generic display mux (1 input, 2 outputs)
> >
> > What makes it generic? Doesn't the mux chip have power supply,
> > possibly a reset line or not, etc.? What about a mux where the GPIO
> > controls the mux?
> >
> > Generally, we avoid 'generic' bindings because h/w is rarely generic.
> > You can have a generic driver which works on multiple devices.
> >
> Then how about making it mt8173-oak-gpio-mux? Since this is currently
> only used in this board.

Isn't there an underlying part# you can use? Or if you can point me to 
multiple chips implementing the same thing, then maybe a generic binding 
is fine.

Rob