[PATCH] powerpc: Add I2C bus multiplexer node for B4 and T4240QDS

[Jia Hongtao-B38951]

Hi Wei,

I totally agree that the i2c nodes topology should end up like you said.

But I think adding sub-nodes should step by step.
Actually the hardware i2c topology are huge like on T4.
So I'd like to adding nodes when we needed.
If you think the sub-nodes are needed please send another patch based on mine.
I think this is the more reasonable way.

Thanks.

-Hongtao


> -----Original Message-----
> From: Yang,Wei [mailto:Wei.Yang at windriver.com]
> Sent: Wednesday, September 04, 2013 9:27 AM
> To: Jia Hongtao-B38951
> Cc: linuxppc-dev at lists.ozlabs.org; Wood Scott-B07421; Jia Hongtao-B38951
> Subject: Re: [PATCH] powerpc: Add I2C bus multiplexer node for B4 and
> T4240QDS
> 
> On 09/03/2013 03:51 PM, Jia Hongtao wrote:
> > In both B4 and T4240QDS platform PCA9547 I2C bus multiplexer is used.
> 
> Hi Hongtao,
> 
> If you want to support I2C bus multiplexer, for T4 and B4QDS platform,
> since some eeprom devices is connected to PCA9574 I2C bus multiplexer, so
> these devices should be connected to pca9547 node. Just like the
> following, what do you think of it?
> 
> +                       pca9547 at 77 {
> +                               compatible = "philips,pca9547";
> +                               reg = <0x77>;
> +                               #address-cells = <1>;
> +                               #size-cells = <0>;
> +                               channel at 0 {
> +                                       #address-cells = <1>;
> +                                       #size-cells = <0>;
> +                                       reg = <0>;
> +                                               eeprom at 51 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x51>;
> +                                               };
> +                                               eeprom at 52 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x52>;
> +                                               };
> +                                               eeprom at 53 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x53>;
> +                                               };
> +                                               eeprom at 54 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x54>;
> +                                               };
> +                                               eeprom at 55 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x55>;
> +                                               };
> +                                               eeprom at 56 {
> +                                                       compatible =
> "at24,24c256";
> +                                                       reg = <0x56>;
> +                                               };
> +                                               rtc at 68 {
> +                                                       compatible =
> "dallas,ds3232";
> +                                                       reg = <0x68>;
> +                                                       interrupts =
> <0x1 0x1 0 0>;
> +                                               };
> +                                       };
> 
> Wei
> >
> > Signed-off-by: Jia Hongtao <hongtao.jia at freescale.com>
> > ---
> >   arch/powerpc/boot/dts/b4qds.dtsi   | 4 ++++
> >   arch/powerpc/boot/dts/t4240qds.dts | 4 ++++
> >   2 files changed, 8 insertions(+)
> >
> > diff --git a/arch/powerpc/boot/dts/b4qds.dtsi
> > b/arch/powerpc/boot/dts/b4qds.dtsi
> > index e6d2f8f..2aa3399 100644
> > --- a/arch/powerpc/boot/dts/b4qds.dtsi
> > +++ b/arch/powerpc/boot/dts/b4qds.dtsi
> > @@ -120,6 +120,10 @@
> >   		};
> >
> >   		i2c at 118000 {
> > +			pca9547 at 77 {
> > +				compatible = "philips,pca9547";
> > +				reg = <0x77>;
> > +			};
> >   			eeprom at 50 {
> >   				compatible = "at24,24c64";
> >   				reg = <0x50>;
> > diff --git a/arch/powerpc/boot/dts/t4240qds.dts
> > b/arch/powerpc/boot/dts/t4240qds.dts
> > index 0555976..084db57 100644
> > --- a/arch/powerpc/boot/dts/t4240qds.dts
> > +++ b/arch/powerpc/boot/dts/t4240qds.dts
> > @@ -118,6 +118,10 @@
> >   		};
> >
> >   		i2c at 118000 {
> > +			pca9547 at 77 {
> > +				compatible = "philips,pca9547";
> > +				reg = <0x77>;
> > +			};
> >   			eeprom at 51 {
> >   				compatible = "at24,24c256";
> >   				reg = <0x51>;
>