[PATCH v5 2/5] dt-bindings: pwm: amlogic: Add a new binding for meson8 pwm types

Jerome Brunet
2024-02-21T15:12:10Z

The binding that is used up to now describe which input the PWM
channel multiplexer should pick among its possible parents,
which are hardcoded in the driver. This isn't a good binding in
the sense that it should describe hardware but not usage.

Add a new binding deprecating the old one that uses clocks in a
better way and how clocks are usually used today: The list of
clocks describe the inputs of the PWM block as they are realised
in hardware.

So deprecate the old bindings and introduce a compatible per SoC
family to replace these.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
.../devicetree/bindings/pwm/pwm-amlogic.yaml | 50 +++++++++++++++++--
1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml b/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
index a1d382aacb82..1d71d4f8f328 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
+++ b/Documentation/devicetree/bindings/pwm/pwm-amlogic.yaml
@@ -21,23 +21,36 @@ properties:
- amlogic,meson-g12a-ee-pwm
- amlogic,meson-g12a-ao-pwm-ab
- amlogic,meson-g12a-ao-pwm-cd
- - amlogic,meson-s4-pwm
+ deprecated: true
- items:
- const: amlogic,meson-gx-pwm
- const: amlogic,meson-gxbb-pwm
+ deprecated: true
- items:
- const: amlogic,meson-gx-ao-pwm
- const: amlogic,meson-gxbb-ao-pwm
+ deprecated: true
- items:
- const: amlogic,meson8-pwm
- const: amlogic,meson8b-pwm
+ deprecated: true
+ - enum:
+ - amlogic,meson8-pwm-v2
+ - amlogic,meson-s4-pwm
+ - items:
+ - enum:
+ - amlogic,meson8b-pwm-v2
+ - amlogic,meson-gxbb-pwm-v2
+ - amlogic,meson-axg-pwm-v2
+ - amlogic,meson-g12-pwm-v2
+ - const: amlogic,meson8-pwm-v2

reg:
maxItems: 1

clocks:
minItems: 1
- maxItems: 2
+ maxItems: 4

clock-names:
minItems: 1
@@ -68,11 +81,14 @@ allOf:
- amlogic,meson-g12a-ao-pwm-ab
- amlogic,meson-g12a-ao-pwm-cd
then:
- # Historic bindings tied to the driver implementation
+ # Obsolete historic bindings tied to the driver implementation
# The clocks provided here are meant to be matched with the input
# known (hard-coded) in the driver and used to select pwm clock
# source. Currently, the linux driver ignores this.
+ # This is kept to maintain ABI backward compatibility.
properties:
+ clocks:
+ maxItems: 2
clock-names:
oneOf:
- items:
@@ -81,6 +97,27 @@ allOf:
- const: clkin0
- const: clkin1

+ # Newer binding where clock describe the actual clock inputs of the pwm
+ # block. These are necessary but some inputs may be grounded.
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - amlogic,meson8-pwm-v2
+ then:
+ properties:
+ clocks:
+ minItems: 1
+ items:
+ - description: input clock 0 of the pwm block
+ - description: input clock 1 of the pwm block
+ - description: input clock 2 of the pwm block
+ - description: input clock 3 of the pwm block
+ clock-names: false
+ required:
+ - clocks
+
# Newer IP block take a single input per channel, instead of 4 inputs
# for both channels
- if:
@@ -110,6 +147,13 @@ examples:
clock-names = "clkin0", "clkin1";
#pwm-cells = <3>;
};
+ - |
+ pwm@2000 {
+ compatible = "amlogic,meson8-pwm-v2";
+ reg = <0x1000 0x10>;
+ clocks = <&xtal>, <0>, <&fdiv4>, <&fdiv5>;
+ #pwm-cells = <3>;
+ };
- |
pwm@1000 {
compatible = "amlogic,meson-s4-pwm";
--
2.43.0