Hi Rob,
On 9/16/24 9:33 AM, Rob Herring wrote:
On Fri, Sep 13, 2024 at 07:34:27AM +0300, Dmitry Baryshkov wrote:
On Thu, Sep 12, 2024 at 04:26:25PM GMT, Amit Sunil Dhamne wrote:
Hi Dmitry,
On 9/12/24 3:05 AM, Dmitry Baryshkov wrote:
On Tue, Sep 10, 2024 at 05:07:05PM GMT, Amit Sunil Dhamne wrote:
This commit adds a new property "pd-timers" to enable setting of
platform/board specific pd timer values for timers that have a range of
acceptable values.
Cc: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Signed-off-by: Amit Sunil Dhamne <amitsd@xxxxxxxxxx>
---
.../bindings/connector/usb-connector.yaml | 23 +++++++++++++++++++
include/dt-bindings/usb/pd.h | 8 +++++++
2 files changed, 31 insertions(+)
diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
index fb216ce68bb3..9be4ed12f13c 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
+++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
@@ -253,6 +253,16 @@ properties:
additionalProperties: false
+ pd-timers:
+ description: An array of u32 integers, where an even index (i) is the timer (referenced in
+ dt-bindings/usb/pd.h) and the odd index (i+1) is the timer value in ms (refer
+ "Table 6-68 Time Values" of "USB Power Delivery Specification Revision 3.0, Version 1.2 " for
+ the appropriate value). For certain timers the PD spec defines a range rather than a fixed
+ value. The timers may need to be tuned based on the platform. This dt property allows the user
+ to assign specific values based on the platform. If these values are not explicitly defined,
+ TCPM will use a valid default value for such timers.
+ $ref: /schemas/types.yaml#/definitions/uint32-array
Is it really necessary to use the array property? I think it's easier
and more logical to define corresponding individual properties, one per
the timer.
Thanks for the review. The reason I did it this way was for
convenience. If in the future someone else wants add a new timer,
it'd be convenient to just add it as a new macro definition in pd.h
rather than having to define a new property each time, especially
if folks want to add more timers (scales better).
There are 3 timers already and I am working to add a fourth in a
follow up patch if the current RFC gets accepted.
Please let me know what do you think?
I'd leave the decision to DT maintainers, but in my opinion multiple
properties scale better. Having a single value per property is easier to
handle rather than changing the tagged array.
I agree. And it avoids what looks like a made up number space with the
defines.
And note that an array of tuples is a matrix in DT defined types, not
an array.
Thanks for the review! I will incorporate the suggested comments in the
next revision by creating a "single value per timer" property.
Regards,
Amit
Rob
