On 22.01.2024 14:56:09, Conor Dooley wrote:

On Mon, Jan 22, 2024 at 03:46:04PM +0100, Marc Kleine-Budde wrote:

quoted

On 22.01.2024 14:21:04, Conor Dooley wrote:

quoted

On Mon, Jan 22, 2024 at 02:13:16PM +0100, Marc Kleine-Budde wrote:

quoted

On 22.01.2024 12:19:50, Conor Dooley wrote:

quoted

From: Conor Dooley <conor.dooley@microchip.com>

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@microchip.com>
---
 .../devicetree/bindings/net/can/microchip,mpfs-can.yaml     | 6 ++++--
 1 file changed, 4 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..01e4d4a54df6 100644
--- a/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml
+++ b/Documentation/devicetree/bindings/net/can/microchip,mpfs-can.yaml

@@ -24,7 +24,9 @@ properties:
     maxItems: 1
 
   clocks:
-    maxItems: 1
+    items:
+      - description: AHB peripheral clock
+      - description: CAN bus clock

What about adding clock-names, so that the order can be checked
automatically?

I don't personally care for doing so, but if your heart is set on having
them, then sure.

Usually the CAN driver needs to have the clock rate of the clocks that
the basis for the CAN bus clock. Looking at the clocks description it's
probably the 2nd one.

With clock-names we can automatically check that the 2nd clock is always
the CAN clock.

I think we already had this discussion on v1, where I said that the
binding requires the clocks to be in that order, regardless of whether
or not clock-names is provided. You feel more strongly about it than I
do, so I will add them when I get around to sending a v3.

Yes, this discussion sounded very familiar to me, never mind. Keep it as
is, and let's get this binding and the CAN driver upstream!

regards,
Marc

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