Re: [PATCH v17 1/3] dt-bindings: Add bindings for Mediatek matrix keypad

[Dmitry Torokhov]

Hi,

On Tue, Aug 11, 2020 at 09:47:23AM +0800, Yingjoe Chen wrote:
> Hi,
> 
> 
> On Mon, 2020-08-10 at 14:40 +0800, Fengping Yu wrote:
> > From: "fengping.yu" <fengping.yu@xxxxxxxxxxxx>
> > 
> > This patch add devicetree bindings for Mediatek matrix keypad driver.
> > 
> > Signed-off-by: fengping.yu <fengping.yu@xxxxxxxxxxxx>
> > ---
> >  .../devicetree/bindings/input/mtk-kpd.yaml    | 87 +++++++++++++++++++
> >  1 file changed, 87 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/input/mtk-kpd.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/input/mtk-kpd.yaml b/Documentation/devicetree/bindings/input/mtk-kpd.yaml
> > new file mode 100644
> > index 000000000000..d74dd8a6fbde
> 
> <...>
> 
> 
> > +  keypad,num-columns:
> > +    description: Number of column lines connected to the keypad controller,
> > +    it is not equal to PCB columns number, instead you should add required value
> > +    for each IC. If not specified, the default value is 1.
> > +
> > +  keypad,num-rows:
> > +    description: Number of row lines connected to the keypad controller, it is
> > +    not equal to PCB rows number, instead you should add required value for each IC.
> > +    If not specified, the default value is 1.
> 
> Your source code can't really handle dts without rows/columns
> properties. Also, the default value doesn't make any sense. No IC will
> have rows or columns set to 1.
> 
> Since these are IC specified, not board specified, I think you should
> just have the correct numbers in driver.

It is actually property of board to decide how many keys it wants to
wire up. In extreme case it will be a single key, i.e. number of rows
and columns will indeed be 1.

Thanks.

-- 
Dmitry