Re: [PATCH 3/3] arm64: dts: qcom: pm8350c: Add pwm support

From: skakit
Date: Thu Sep 09 2021 - 02:11:41 EST


On 2021-09-08 22:38, Bjorn Andersson wrote:
On Wed 08 Sep 08:29 PDT 2021, Matthias Kaehlcke wrote:

On Wed, Sep 08, 2021 at 02:37:39PM +0530, skakit@xxxxxxxxxxxxxx wrote:
> On 2021-09-07 23:46, Matthias Kaehlcke wrote:
> > On Mon, Sep 06, 2021 at 04:11:07PM +0530, satya priya wrote:
> > > Add pwm support for PM8350C pmic.
> > >
> > > Signed-off-by: satya priya <skakit@xxxxxxxxxxxxxx>
> > > ---
> > > arch/arm64/boot/dts/qcom/pm8350c.dtsi | 6 ++++++
> > > 1 file changed, 6 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/qcom/pm8350c.dtsi
> > > b/arch/arm64/boot/dts/qcom/pm8350c.dtsi
> > > index e1b75ae..ecdae55 100644
> > > --- a/arch/arm64/boot/dts/qcom/pm8350c.dtsi
> > > +++ b/arch/arm64/boot/dts/qcom/pm8350c.dtsi
> > > @@ -29,6 +29,12 @@
> > > interrupt-controller;
> > > #interrupt-cells = <2>;
> > > };
> > > +
> > > + pm8350c_pwm4: pwm {
> >
> > What does the '4' represent, an internal channel number? It should
> > probably be omitted if the PM8350 only has a single output PWM
> > port.
> >
>
> pm8350c has four PWMs, but I think we can drop the '4' here.

Why is only one PWM exposed if the PMIC has for of them? Why number 4
and not one of the others?


pwm4 is used for backlight support on kodiak crd board, so I mentioned 4, thinking 4 nodes should be present for 4 pwms.
but I see that we need to represent all the four channels as one node. will drop the '4' in next version.

Thanks,
Satya Priya

The node should represent all 4 channels, which ones the board uses is
captured in how they are bound to other clients - or defines as LEDs by
additional child nodes.

Regards,
Bjorn