Re: [PATCHv2 4/4] Documentation: Add device tree bindings for Freescale FTM PWM.

[Sascha Hauer <s.hauer@pengutronix.de>]

On Mon, Sep 02, 2013 at 02:38:53AM +0000, Xiubo Li-B47053 wrote:
> > Subject: Re: [PATCHv2 4/4] Documentation: Add device tree bindings for
> > Freescale FTM PWM.
> > 
> ...
> > > +
> > > +pwm0: pwm@40038000 {
> > > +		compatible = "fsl,vf610-ftm-pwm";
> > > +		reg = <0x40038000 0x1000>;
> > > +		#pwm-cells = <3>;
> > > +		clock-names = "ftm0", "ftm0_fix_sel", "ftm0_ext_sel";
> > > +		clocks = <&clks VF610_CLK_FTM0>,
> > > +			<&clks VF610_CLK_FTM0_FIX_SEL>,
> > > +			<&clks VF610_CLK_FTM0_EXT_SEL>;
> > > +		pinctrl-names = "ch0-active", "ch0-idle", "ch1-active", "ch1-
> > idle",
> > > +		....;
> > > +		pinctrl-0 = <&pinctrl_pwm0_ch0_active>;
> > > +		pinctrl-1 = <&pinctrl_pwm0_ch0_idle>;
> > > +		pinctrl-2 = <&pinctrl_pwm0_ch1_active>;
> > > +		pinctrl-3 = <&pinctrl_pwm0_ch1_idle>;
> > > +		...
> > > +		fsl,pwm-counter-clk = "ftm0_ext_sel";
> > > +		fsl,pwm-avaliable-chs = <0 3 5 6>;
> > 
> > I don't think this proerty is useful. Just enable all channels. I think
> > this was mentioned before.
> > 
> Yes.
> Actully this property is located in board level dts file.
> I have added and requested all the channels in SoC level dtsi file,
> and in board level dts file to tell the customer the limitation, I
> think is much safter and better.

Why should this be in the board file? A pwm that is not available should
simply not be referenced and thus be unused. No need to explicitly
disable it.

Sascha

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