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?
Regards,
Amit
+
dependencies:
sink-vdos-v1: [ sink-vdos ]
sink-vdos: [ sink-vdos-v1 ]
@@ -478,3 +488,16 @@ examples:
};
};
};
+
+ # USB-C connector with PD timers
+ - |
+ #include <dt-bindings/usb/pd.h>
+ usb {
+ connector {
+ compatible = "usb-c-connector";
+ label = "USB-C";
+ pd-timers =
+ <PD_TIMER_SINK_WAIT_CAP 600>,
+ <PD_TIMER_CC_DEBOUNCE 170>;
+ };
+ };
diff --git a/include/dt-bindings/usb/pd.h b/include/dt-bindings/usb/pd.h
index e6526b138174..6c58c30f3f39 100644
--- a/include/dt-bindings/usb/pd.h
+++ b/include/dt-bindings/usb/pd.h
@@ -465,4 +465,12 @@
| ((vbm) & 0x3) << 15 | (curr) << 14 | ((vbi) & 0x3f) << 7 \
| ((gi) & 0x3f) << 1 | (ct))
+/* PD Timer definitions */
+/* tTypeCSinkWaitCap (Table 6-68 Time Values, USB PD3.1 Spec) */
+#define PD_TIMER_SINK_WAIT_CAP 0
+/* tPSSourceOff (Table 6-68 Time Values, USB PD3.1 Spec) */
+#define PD_TIMER_PS_SOURCE_OFF 1
+/* tCCDebounce (Table 4-33 CC Timing, USB Type-C Cable & Connector Spec Rel2.2) */
+#define PD_TIMER_CC_DEBOUNCE 2
+
#endif /* __DT_POWER_DELIVERY_H */
--
2.46.0.598.g6f2099f65c-goog
