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authorSebastian Reichel <sebastian.reichel@collabora.co.uk>2017-09-04 18:30:03 +0200
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2017-09-04 21:13:24 +0200
commit3e5b08518f6aefad31dca975634c3133457928ff (patch)
tree7b81f87a03f735cb096dea772d390087b4b7dad7 /Documentation
parentInput: adi - make array seq static, reduces object code size (diff)
downloadlinux-3e5b08518f6aefad31dca975634c3133457928ff.tar.xz
linux-3e5b08518f6aefad31dca975634c3133457928ff.zip
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>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/input/pwm-vibrator.txt66
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
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+++ b/Documentation/devicetree/bindings/input/pwm-vibrator.txt
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+* 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>;
+ };
+};