RE: [PATCH V4 RESEND 1/2] dt-bindings/irq: add binding for NXP INTMUX interrupt multiplexer

[Joakim Zhang <qiangqing.zhang@nxp.com>]

> -----Original Message-----
> From: Joakim Zhang <qiangqing.zhang@nxp.com>
> Sent: 2020年1月14日 10:44
> To: Rob Herring <robh@kernel.org>
> Cc: maz@kernel.org; jason@lakedaemon.net; tglx@linutronix.de;
> mark.rutland@arm.com; shawnguo@kernel.org; s.hauer@pengutronix.de;
> kernel@pengutronix.de; festevam@gmail.com; linux-kernel@vger.kernel.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; dl-linux-imx
> <linux-imx@nxp.com>; Andy Duan <fugang.duan@nxp.com>
> Subject: RE: [PATCH V4 RESEND 1/2] dt-bindings/irq: add binding for NXP
> INTMUX interrupt multiplexer
> 
> 
> > -----Original Message-----
> > From: Rob Herring <robh@kernel.org>
> > Sent: 2020年1月14日 5:04
> > To: Joakim Zhang <qiangqing.zhang@nxp.com>
> > Cc: maz@kernel.org; jason@lakedaemon.net; tglx@linutronix.de;
> > mark.rutland@arm.com; shawnguo@kernel.org; s.hauer@pengutronix.de;
> > kernel@pengutronix.de; festevam@gmail.com;
> > linux-kernel@vger.kernel.org; devicetree@vger.kernel.org;
> > linux-arm-kernel@lists.infradead.org; dl-linux-imx
> > <linux-imx@nxp.com>; Andy Duan <fugang.duan@nxp.com>
> > Subject: Re: [PATCH V4 RESEND 1/2] dt-bindings/irq: add binding for
> > NXP INTMUX interrupt multiplexer
> >
> > On Mon, Jan 13, 2020 at 03:08:40PM +0800, Joakim Zhang wrote:
> > > This patch adds the DT bindings for the NXP INTMUX interrupt
> > > multiplexer for i.MX8 family SoCs.
> > >
> > > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
> > > ---
> > >  .../interrupt-controller/fsl,intmux.yaml      | 77
> +++++++++++++++++++
> > >  1 file changed, 77 insertions(+)
> > >  create mode 100644
> > > Documentation/devicetree/bindings/interrupt-controller/fsl,intmux.ya
> > > ml
> >
> > Please run 'make dt_binding_check' and fix the errors:
> >
> > Documentation/devicetree/bindings/interrupt-controller/fsl,intmux.yaml:
> > while scanning for the next token found character that cannot start any token
> >   in "<unicode string>", line 60, column 1
> Got it. Will keep in mind. Thanks.
> 
> > >
> > > diff --git
> > > a/Documentation/devicetree/bindings/interrupt-controller/fsl,intmux.
> > > ya
> > > ml
> > > b/Documentation/devicetree/bindings/interrupt-controller/fsl,intmux.
> > > ya
> > > ml
> > > new file mode 100644
> > > index 000000000000..4dba532fe0bd
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/interrupt-controller/fsl,int
> > > +++ mu
> > > +++ x.yaml
> > > @@ -0,0 +1,77 @@
> > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) %YAML 1.2
> > > +---
> > > +$id:
> > > +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fde
> > > +vi
> > >
> >
> +cetree.org%2Fschemas%2Finterrupt-controller%2Ffsl%2Cintmux.yaml%23&a
> > m
> > >
> >
> +p;data=02%7C01%7Cqiangqing.zhang%40nxp.com%7Cdc2443dc111149805c7
> > 208d7
> > >
> >
> +986c157f%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C63714546
> > 2291934
> > >
> >
> +492&amp;sdata=Ao4iuj2D48KAeC%2FvQvJqUUxGJEjSY0HyL5ZlT2XrSrg%3D&
> > amp;re
> > > +served=0
> > > +$schema:
> > > +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fde
> > > +vi
> > >
> >
> +cetree.org%2Fmeta-schemas%2Fcore.yaml%23&amp;data=02%7C01%7Cqia
> > ngqing
> > >
> >
> +.zhang%40nxp.com%7Cdc2443dc111149805c7208d7986c157f%7C686ea1d3b
> > c2b4c6
> > >
> >
> +fa92cd99c5c301635%7C0%7C0%7C637145462291934492&amp;sdata=YoHb
> > TO5C8Nlq
> > > +YYoWTNufaIxnvdtPUZaKzvwK49I9Zdc%3D&amp;reserved=0
> > > +
> > > +title: Freescale INTMUX interrupt multiplexer
> > > +
> > > +maintainers:
> > > +  - Marc Zyngier <maz@kernel.org>
> > > +
> > > +properties:
> > > +  compatible:
> > > +    items:
> > > +      const: fsl,imx-intmux
> > > +
> > > +  reg:
> > > +    maxItems: 1
> > > +
> > > +  interrupts:
> > > +    minItems: 1
> > > +    maxItems: 8
> > > +    description: |
> > > +      Should contain the parent interrupt lines (up to 8) used to multiplex
> > > +      the input interrupts.
> > > +
> > > +  interrupt-controller: true
> > > +
> > > +  '#interrupt-cells':
> > > +    const: 2
> > > +
> > > +  clocks:
> > > +    maxItems: 1
> > > +    description: ipg clock.
> > > +
> > > +  clock-names:
> > > +    items:
> > > +      const: ipg
> > > +
> > > +  fsl,intmux_chans:
> >
> > Don't use '_' in property names.
> Got it.
> 
> > Is this any different from the length of 'interrupts' which you can count?
> A bit different. Such as, the length of 'interrupts' is 8, but we can set
> fsl,intmux_chans value is 4. That means there are 8 channels, but actually we
> only use 4 channels.
> If you think this make no sense, due to we can assign 4 items for 'interrupts' to
> get the same result. So we can count the length of 'interrupts' to get the
> channels configured, then this property is no need.
> Which one do you think is better?
> 		interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 17 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 22 IRQ_TYPE_LEVEL_HIGH>,
> 			     <GIC_SPI 23 IRQ_TYPE_LEVEL_HIGH>;
> 		fsl,intmux_chans = <4>;

One more add, the number of channels is fixed to 8. It will make more clear to users that it supports 8 channels with 8 items for 'interrupts', and users can decide how many
channels they use with 'fsl,intmux_chans' property.

Best Regards,
Joakim Zhang
> Best Regards,
> Joakim Zhang
> > > +    maxItems: 1
> > > +    description: |
> > > +      The number of channels used for interrupt source. The Maximum
> > value is 8.
> > > +      If this property is not set in DT then driver uses 1 channel by
> default.
> > > +
> > > +required:
> > > +  - compatible
> > > +  - reg
> > > +  - interrupts
> > > +  - interrupt-controller
> > > +  - '#interrupt-cells'
> > > +  - clocks
> > > +  - clock-name
> > > +  - fsl,intmux_chans
> > > +
> > > +additionalProperties: false
> > > +
> > > +Example:
> > > +
> > > +	intmux@37400000 {
> >
> > interrupt-controller@...
> >
> > > +		compatible = "fsl,imx-intmux";
> > > +		reg = <0x37400000 0x1000>;
> > > +		interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 17 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 22 IRQ_TYPE_LEVEL_HIGH>,
> > > +			     <GIC_SPI 23 IRQ_TYPE_LEVEL_HIGH>;
> > > +		interrupt-controller;
> > > +		#interrupt-cells = <2>;
> > > +		clocks = <&clk IMX8QM_CM40_IPG_CLK>;
> > > +		clock-names = "ipg";
> > > +		fsl,intmux_chans = <8>;
> > > +	};
> > > +
> > > --
> > > 2.17.1
> > >