[PATCH v2 4/5] dt-bindings: clock: mediatek: update audsys documentation to adapt MFD device
ryder.lee at mediatek.com
Wed Feb 7 21:51:05 PST 2018
On Wed, 2018-02-07 at 18:49 -0600, Rob Herring wrote:
> >> > diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt b/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt
> >> > index 9b8f578..677af40 100644
> >> > --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt
> >> > +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt
> >> > @@ -1,22 +1,45 @@
> >> > -MediaTek AUDSYS controller
> >> > +MediaTek Audio Subsystem
> >> > ============================
> >> > +The audio subsystem is one of the multi-function blocks of MediaTek SoCs.
> >> > +It contains a system controller, which provides a number registers giving
> >> > +access to two features: AUDSYS clocks and Audio Front End (AFE) components.
> >> >
> >> > +For the top level node:
> >> > +- compatible: must be: "syscon", "simple-mfd";
> >> This should have some SoC specific compatible.
> > As we don't have a specific driver (compatible string) for it and if we
> > need to add that I think the term '*-audsys' is very suitable here, but
> > unfortunately, it has already picked for clock driver (see child node).
> Perhaps the clocks block should have "-clk" on the end or something.
> Why do you really need to change this in the first place? You don't
> have to have DT child nodes to create child (struct) devices and child
I'm not sure I get your point. Did you mean that we could have a parent
(which represents clock and its compatible is something like
"*-audsys","syscon","simple-mfd") with a subnode for audio function?
If so, there's no special reason. I just think it more specifically to
let people know we have an MFD (top node) and it has two sub-functions
(children) share the same region.
> >> > +Required sub-nodes:
> >> > +
> >> > +AUDSYS clocks:
> >> > +-------
> >> > The MediaTek AUDSYS controller provides various clocks to the system.
> >> >
> >> > Required Properties:
> >> >
> >> > - compatible: Should be one of:
> >> > - - "mediatek,mt7622-audsys", "syscon"
> >> > + - "mediatek,mt2701-audsys";
> >> > + - "mediatek,mt7622-audsys";
> >> > - #clock-cells: Must be 1
> >> >
> >> > The AUDSYS controller uses the common clk binding from
> >> > Documentation/devicetree/bindings/clock/clock-bindings.txt
> >> > The available clocks are defined in dt-bindings/clock/mt*-clk.h.
> >> There's no register range associated with the clocks? If there is, add a
> >> reg property.
> > No, we don't need reg property here, as the two sub-drivers will obtain
> > the regmap which is propagated from the parent.
> I know regmap doesn't need it. That's not what I asked. If you have a
> range of registers for the clocks, then define that in reg. Only if
> the clock control bits are mixed up with other functions within the
> same registers, then you can omit it.
Oh okay, I didn't read the mail well. We have four or five registers
for the clocks, but one of them (offset:0x634) is mixed up with the
audio function (bit 17-19), so I omit it.
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