Re: [PATCH RESEND v1 2/7] dt-bindings: can: mpfs: add missing required clock

From: Conor Dooley
Date: Thu Dec 14 2023 - 08:17:11 EST


On Thu, Dec 14, 2023 at 12:31:04PM +0100, Marc Kleine-Budde wrote:
> On 13.12.2023 13:02:49, Conor Dooley wrote:
> > On Tue, Dec 12, 2023 at 09:49:41PM +0100, Marc Kleine-Budde wrote:
> > > On 08.12.2023 17:12:24, Conor Dooley wrote:
> > > > From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> > > >
> > > > The CAN controller on PolarFire SoC has an AHB peripheral clock _and_ a
> > > > CAN bus clock. The bus clock was omitted when the binding was written,
> > > > but is required for operation. Make up for lost time and add it.
> > > >
> > > > Cautionary tale in adding bindings without having implemented a real
> > > > user for them perhaps.
> > > >
> > > > Fixes: c878d518d7b6 ("dt-bindings: can: mpfs: document the mpfs CAN controller")
> > > > Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> > > > ---
> > > > .../devicetree/bindings/net/can/microchip,mpfs-can.yaml | 7 +++++--
> > > > 1 file changed, 5 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml b/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml
> > > > index 45aa3de7cf01..05f680f15b17 100644
> > > > --- a/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml
> > > > +++ b/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml
> > > > @@ -24,7 +24,10 @@ properties:
> > > > maxItems: 1
> > > >
> > > > clocks:
> > > > - maxItems: 1
> > > > + maxItems: 2
> > > > + items:
> > > > + - description: AHB peripheral clock
> > > > + - description: CAN bus clock
> > >
> > > Do we we want to have a "clock-names" property, as we need the clock
> > > rate of the CAN bus clock.
> >
> > We should not need the clock-names property to be able to get both of
> > the clocks. clk_bulk_get_all() for example should be usable here.
>
> ACK, but we need the clock rate of CAN clock. Does this binding check
> that the CAN clock rate is the 2nd one?

The items list requires that the can clock be the second one, so drivers
etc can rely on that ordering.

Attachment: signature.asc
Description: PGP signature