lkml.org 
[lkml]   [2014]   [Apr]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v4 1/3] i2c: cadence: Document device tree bindings
On Fri, 2014-04-04 at 09:17PM +0200, Gerhard Sittig wrote:
> On Thu, 2014-04-03 at 10:59 -0700, Soren Brinkmann wrote:
> >
> > Add device tree binding documentation for the Cadence I2C controller.
> >
> > [ ... ]
> >
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-cadence.txt
> > @@ -0,0 +1,21 @@
> > +Binding for the Cadence I2C controller
> > +
> > +Required properties:
> > + compatible: Compatibility string. Must be 'cdns,i2c-r1p10'.
> > + clocks: From common clock bindings. Phandle to input clock.
>
> the usual complaint: 'clocks' items are not just phandles (your
> example even suggests this); either adjust the description to
> something correct, or just refer to the common clock bindings to
> not duplicate their description

I'll figure out something.

>
> but I guess the I2C controller's binding should explicitly state
> which clocks are required, and you might want to consider
> 'clock-names', too

There is only one clock input. There is no need to overcomplicate things
by adding clock-names.

>
> > +
> > +Optional properties:
> > + clock-frequency: Desired operating frequency, in Hz, of the bus (actual may
> > + be lower). Defaults to 400000 if not specified.
>
> is the value default a feature of the Linux implementation, or
> consciously designed to be in the binding spec? and I agree that
> the default should be the standard I2C speed instead of fast mode

I remove the note regarding the default. It's implementation.

>
> > +
> > +Example:
> > +
> > + i2c@e0004000 {
> > + compatible = "cdns,i2c-r1p10";
> > + clocks = <&clkc 38>;
> > + interrupts = <0 25 4>;
> > + reg = <0xE0004000 0x1000>;
> > + clock-frequency = <400000>;
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > + };
>
> use lower case hex digits, consider symbolic identifiers for
> clocks and interrupt flags

I don't care about the case of those hex digits, but where does it say
that they have to be lower case? Will somebody complain about usage of
lower case chars next?

>
> the example has many more properties than the binding describes,
> the additional items aren't even optional -- you might want to
> refer to a few more common or general bindings

Well, this is common across binding documentation. Can we please get
consistency in this? I see plenty of binding docs that are documented
this way, not mentioning much regarding such common properties.

Sören


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2014-04-04 23:41    [W:0.081 / U:1.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site