Re: [PATCH v2 02/18] dt-bindings: timer: sp804: add timer-width property

[Robin Murphy]

Hi Rob,

On 17/03/16 17:09, Rob Herring wrote:
> On Wed, Mar 09, 2016 at 11:24:04AM +0100, Neil Armstrong wrote:
> > Add timer-width optional property to specify a different vendor
> > specific timer counter bit-width.
> >
> > Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> > ---
> >   Documentation/devicetree/bindings/timer/arm,sp804.txt | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/timer/arm,sp804.txt b/Documentation/devicetree/bindings/timer/arm,sp804.txt
> > index 5cd8eee7..141e143 100644
> > --- a/Documentation/devicetree/bindings/timer/arm,sp804.txt
> > +++ b/Documentation/devicetree/bindings/timer/arm,sp804.txt
> > @@ -17,6 +17,8 @@ Optional properties:
> >   - arm,sp804-has-irq = <#>: In the case of only 1 timer irq line connected, this
> >   	specifies if the irq connection is for timer 1 or timer 2. A value of 1
> >   	or 2 should be used.
> > +- arm,timer-width: Should contain the width in number of bits of the counter,
> > +	is considered by default 32 but can be changed for vendor variants.
>
> That would not be an SP804 nor would the vendor be ARM in that case. So
> add a new compatible string for the vendor that decided to hack up ARM's
> IP block.

By all accounts this is some ancient reference design[1] which later 
evolved _into_ the SP804, so that vendor would probably still be ARM ;)

A separate compatible string would indeed make more sense, though. Both 
semantically and in terms of letting the driver account for the 
differences automatically.

Robin.

[1]:http://infocenter.arm.com/help/topic/com.arm.doc.ddi0170a/I350250.html

> Rob
>
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