[PATCH V4 3/3] powerpc/85xx: Add TWR-P1025 board support

[Xiaobo Xie]

Hi Scott,

> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Friday, September 27, 2013 5:27 AM
> To: Xie Xiaobo-R63061
> Cc: Wood Scott-B07421; linuxppc-dev at lists.ozlabs.org; Johnston Michael-
> R49610
> Subject: Re: [PATCH V4 3/3] powerpc/85xx: Add TWR-P1025 board support
> 
> > > > > > +	/* CS2 for Display */
> > > > > > +	ssd1289 at 2,0 {
> > > > > > +		#address-cells = <1>;
> > > > > > +		#size-cells = <1>;
> > > > > > +		compatible = "ssd1289";
> > > > > > +		reg = <0x2 0x0000 0x0002
> > > > > > +		       0x2 0x0002 0x0002>;
> > > > > > +	};
> > > > >
> > > > > Node names should be generic.  What does ssd1289 do?  If this is
> > > > > actually the display device, then it should be called
> "display at 2,0".
> > > >
> > > > OK. The ssd1289 is a LCD controller.
> > > >
> > > > >
> > > > > How about a vendor prefix on that compatible?  Why
> > > > > #address-cells/#size- cells despite no child nodes?  Where is a
> > > > > binding that says what each of those two reg resources mean?
> > > >
> > > > I will add the vendor prefix. I review the ssd1289 driver, and the
> > > #address-cells/#size-cells were un-used. I will remove them.
> > >
> > > And a binding?
> > >
> > > Why do you need two separate reg resources rather than just <2 0 4>?
> > > Will they ever be discontiguous?
> >
> > [Xie] I review the ssd1289 driver code, and found the driver need two
> > reg resources,
> 
> The device tree describes the hardware, not the current state of Linux
> drivers.  Especially drivers that aren't yet in Linux. :-)
> 

OK, I will remain the display node.

> > if change the dts, the driver also should be modified accordingly. So
> > I remove the ssd1289 node from this patch. I will submit new patch
> > include the dts modification, ssd1289 driver and the binding.
> 
> Ideally all devices (and bindings) should be described when the device
> tree is initally added, regardless of whether you have a driver yet.
> 
 
I will add a binding document for the ssd1289 device.

> -Scott
> 
- Xiaobo