dt-bindings: counter: Document stm32 quadrature encoder

Add bindings for STM32 Timer quadrature encoder.
It is a sub-node of STM32 Timer which implement the
quadratic encoder part of the hardware.

Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/counter/stm32-timer-cnt.txt b/Documentation/devicetree/bindings/counter/stm32-timer-cnt.txt
new file mode 100644 (file)
index 0000000..c52fcdd
--- /dev/null
+++ b/Documentation/devicetree/bindings/counter/stm32-timer-cnt.txt
@@ -0,0 +1,31 @@
+STMicroelectronics STM32 Timer quadrature encoder
+
+STM32 Timer provides quadrature encoder to detect
+angular position and direction of rotary elements,
+from IN1 and IN2 input signals.
+
+Must be a sub-node of an STM32 Timer device tree node.
+See ../mfd/stm32-timers.txt for details about the parent node.
+
+Required properties:
+- compatible:          Must be "st,stm32-timer-counter".
+- pinctrl-names:       Set to "default".
+- pinctrl-0:           List of phandles pointing to pin configuration nodes,
+                       to set CH1/CH2 pins in mode of operation for STM32
+                       Timer input on external pin.
+
+Example:
+       timers@40010000 {
+               #address-cells = <1>;
+               #size-cells = <0>;
+               compatible = "st,stm32-timers";
+               reg = <0x40010000 0x400>;
+               clocks = <&rcc 0 160>;
+               clock-names = "int";
+
+               counter {
+                       compatible = "st,stm32-timer-counter";
+                       pinctrl-names = "default";
+                       pinctrl-0 = <&tim1_in_pins>;
+               };
+       };

diff --git a/Documentation/devicetree/bindings/mfd/stm32-timers.txt b/Documentation/devicetree/bindings/mfd/stm32-timers.txt
index 0e900b5..15c3b87 100644 (file)
--- a/Documentation/devicetree/bindings/mfd/stm32-timers.txt
+++ b/Documentation/devicetree/bindings/mfd/stm32-timers.txt
@@ -28,6 +28,7 @@ Optional parameters:
 Optional subnodes:
 - pwm:                 See ../pwm/pwm-stm32.txt
 - timer:               See ../iio/timer/stm32-timer-trigger.txt
+- counter:             See ../counter/stm32-timer-cnt.txt
 
 Example:
        timers@40010000 {
@@ -48,6 +49,12 @@ Example:
                        compatible = "st,stm32-timer-trigger";
                        reg = <0>;
                };
+
+               counter {
+                       compatible = "st,stm32-timer-counter";
+                       pinctrl-names = "default";
+                       pinctrl-0 = <&tim1_in_pins>;
+               };
        };
 
 Example with all dmas: