Input: add a driver for PWM controllable vibrators

Provide a simple driver for PWM controllable vibrators.
It will be used by Motorola Droid 4.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/input/pwm-vibrator.txt b/Documentation/devicetree/bindings/input/pwm-vibrator.txt
new file mode 100644
index 000000000000..09145d18491d
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/pwm-vibrator.txt
@@ -0,0 +1,66 @@
+* PWM vibrator device tree bindings
+
+Registers a PWM device as vibrator. It is expected, that the vibrator's
+strength increases based on the duty cycle of the enable PWM channel
+(100% duty cycle meaning strongest vibration, 0% meaning no vibration).
+
+The binding supports an optional direction PWM channel, that can be
+driven at fixed duty cycle. If available this is can be used to increase
+the vibration effect of some devices.
+
+Required properties:
+- compatible: should contain "pwm-vibrator"
+- pwm-names: Should contain "enable" and optionally "direction"
+- pwms: Should contain a PWM handle for each entry in pwm-names
+
+Optional properties:
+- vcc-supply: Phandle for the regulator supplying power
+- direction-duty-cycle-ns: Duty cycle of the direction PWM channel in
+                           nanoseconds, defaults to 50% of the channel's
+                           period.
+
+Example from Motorola Droid 4:
+
+&omap4_pmx_core {
+        vibrator_direction_pin: pinmux_vibrator_direction_pin {
+                pinctrl-single,pins = <
+                OMAP4_IOPAD(0x1ce, PIN_OUTPUT | MUX_MODE1) /* dmtimer8_pwm_evt (gpio_27) */
+                >;
+        };
+
+        vibrator_enable_pin: pinmux_vibrator_enable_pin {
+                pinctrl-single,pins = <
+                OMAP4_IOPAD(0X1d0, PIN_OUTPUT | MUX_MODE1) /* dmtimer9_pwm_evt (gpio_28) */
+                >;
+        };
+};
+
+/ {
+        pwm8: dmtimer-pwm {
+                pinctrl-names = "default";
+                pinctrl-0 = <&vibrator_direction_pin>;
+
+                compatible = "ti,omap-dmtimer-pwm";
+                #pwm-cells = <3>;
+                ti,timers = <&timer8>;
+                ti,clock-source = <0x01>;
+        };
+
+        pwm9: dmtimer-pwm {
+                pinctrl-names = "default";
+                pinctrl-0 = <&vibrator_enable_pin>;
+
+                compatible = "ti,omap-dmtimer-pwm";
+                #pwm-cells = <3>;
+                ti,timers = <&timer9>;
+                ti,clock-source = <0x01>;
+        };
+
+        vibrator {
+                compatible = "pwm-vibrator";
+                pwms = <&pwm8 0 1000000000 0>,
+                       <&pwm9 0 1000000000 0>;
+                pwm-names = "enable", "direction";
+                direction-duty-cycle-ns = <1000000000>;
+        };
+};