[PATCH 1/2] dt-bindings: phy: imx8mq-usb: improve some tuning properties

[Xu Yang]

Commit b2e75563dc39 ("dt-bindings: phy: imx8mq-usb: add phy tuning
properties") add many tuning properties, but some parameter value doesn't
match the register description. It made some changes based on the original
value: add offset to a negative number so turn it to a non-negative number.
However, this conversion bring many pain when some properties need to be
improved.

Because device-tree supports negative parameter number, this will improve
some propertie's parameter.

Mainly include below properties:
 - fsl,phy-tx-vref-tune-percent
 - fsl,phy-tx-rise-tune-percent
 - fsl,phy-comp-dis-tune-percent

The parameter value of above 3 properties are USB PHY specific. i.MX8MP
and i.MX95 USB PHY has different meanings. So this add restrictions for
them.

 - fsl,phy-tx-vboost-level-microvolt

For this property, the parameter value is wrong in register description.
This will correct it according to true value.

For detailed info, please refer to i.MX8MP and i.MX95 latest reference
manual.

Signed-off-by: Xu Yang <xu.yang_2 at nxp.com>
---
 .../bindings/phy/fsl,imx8mq-usb-phy.yaml      | 43 +++++++++++++++----
 1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml b/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
index daee0c0fc915..b09e3dab4c59 100644
--- a/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
+++ b/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
@@ -43,15 +43,11 @@ properties:
   fsl,phy-tx-vref-tune-percent:
     description:
       Tunes the HS DC level relative to the nominal level
-    minimum: 94
-    maximum: 124
 
   fsl,phy-tx-rise-tune-percent:
     description:
       Adjusts the rise/fall time duration of the HS waveform relative to
       its nominal value
-    minimum: 97
-    maximum: 103
 
   fsl,phy-tx-preemp-amp-tune-microamp:
     description:
@@ -63,15 +59,12 @@ properties:
   fsl,phy-tx-vboost-level-microvolt:
     description:
       Adjust the boosted transmit launch pk-pk differential amplitude
-    minimum: 880
-    maximum: 1120
+    enum: [844, 1008, 1156]
 
   fsl,phy-comp-dis-tune-percent:
     description:
       Adjust the voltage level used to detect a disconnect event at the host
       relative to the nominal value
-    minimum: 91
-    maximum: 115
 
   fsl,phy-pcs-tx-deemph-3p5db-attenuation-db:
     description:
@@ -112,6 +105,40 @@ allOf:
         reg:
           maxItems: 1
 
+  - if:
+      properties:
+        compatible:
+          enum:
+            - fsl,imx8mq-usb-phy
+            - fsl,imx8mp-usb-phy
+    then:
+      properties:
+        fsl,phy-tx-vref-tune-percent:
+          minimum: -6
+          maximum: 24
+        fsl,phy-tx-rise-tune-percent:
+          enum: [-3, -1, 0, 3]
+        fsl,phy-comp-dis-tune-percent:
+          enum: [-9, -6, -3, 0, 4, 7, 11, 15]
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - fsl,imx95-usb-phy
+    then:
+      properties:
+        fsl,phy-tx-vref-tune-percent:
+          description: 100x the original
+          minimum: -1000
+          maximum: 875
+        fsl,phy-tx-rise-tune-percent:
+          enum: [-10, 0, 15, 20]
+        fsl,phy-comp-dis-tune-percent:
+          description: 10x the original
+          enum: [-60, -45, -30, -15, 0, 15, 30, 45]
+
   - if:
       required:
         - orientation-switch
-- 
2.34.1