dt-bindings: usb: ci-hdrc-usb2: add fsl,picophy-rise-fall-time-adjust property

The fsl,picophy-rise-fall-time-adjust property can help to adjust the
rise/fall times of the high-speed transmitter waveform. The value can be
0~3. It has no unit. According to the description of USBNC_n_PHY_CFG1
register, the rise/fall time will be increased or decreased by a certain
percentage relative to design default time if a value is given to this
property.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://lore.kernel.org/r/20230627112126.1882666-2-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml
index 782402800d4ab2aa5dde957c03b558e4444c738d..532d6464c8b33151019ed22124ef7e3079f67a6e 100644 (file)
--- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml
+++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.yaml
@@ -292,6 +292,18 @@ properties:
     minimum: 0x0
     maximum: 0xf
 
+  fsl,picophy-rise-fall-time-adjust:
+    description:
+      HS Transmitter Rise/Fall Time Adjustment. Adjust the rise/fall times
+      of the high-speed transmitter waveform. It has no unit. The rise/fall
+      time will be increased or decreased by a certain percentage relative
+      to design default time. (0:-10%; 1:design default; 2:+15%; 3:+20%)
+      Details can refer to TXRISETUNE0 bit of USBNC_n_PHY_CFG1.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 0
+    maximum: 3
+    default: 1
+
   usb-phy:
     description: phandle for the PHY device. Use "phys" instead.
     $ref: /schemas/types.yaml#/definitions/phandle