--- /dev/null
+* 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>;
+ };
+};
--- /dev/null
+/*
+ * PWM vibrator driver
+ *
+ * Copyright (C) 2017 Collabora Ltd.
+ *
+ * Based on previous work from:
+ * Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
+ *
+ * Based on PWM beeper driver:
+ * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/pwm.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+struct pwm_vibrator {
+ struct input_dev *input;
+ struct pwm_device *pwm;
+ struct pwm_device *pwm_dir;
+ struct regulator *vcc;
+
+ struct work_struct play_work;
+ u16 level;
+ u32 direction_duty_cycle;
+};
+
+static int pwm_vibrator_start(struct pwm_vibrator *vibrator)
+{
+ struct device *pdev = vibrator->input->dev.parent;
+ struct pwm_state state;
+ int err;
+
+ err = regulator_enable(vibrator->vcc);
+ if (err) {
+ dev_err(pdev, "failed to enable regulator: %d", err);
+ return err;
+ }
+
+ pwm_get_state(vibrator->pwm, &state);
+ pwm_set_relative_duty_cycle(&state, vibrator->level, 0xffff);
+ state.enabled = true;
+
+ err = pwm_apply_state(vibrator->pwm, &state);
+ if (err) {
+ dev_err(pdev, "failed to apply pwm state: %d", err);
+ return err;
+ }
+
+ if (vibrator->pwm_dir) {
+ pwm_get_state(vibrator->pwm_dir, &state);
+ state.duty_cycle = vibrator->direction_duty_cycle;
+ state.enabled = true;
+
+ err = pwm_apply_state(vibrator->pwm_dir, &state);
+ if (err) {
+ dev_err(pdev, "failed to apply dir-pwm state: %d", err);
+ pwm_disable(vibrator->pwm);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static void pwm_vibrator_stop(struct pwm_vibrator *vibrator)
+{
+ regulator_disable(vibrator->vcc);
+
+ if (vibrator->pwm_dir)
+ pwm_disable(vibrator->pwm_dir);
+ pwm_disable(vibrator->pwm);
+}
+
+static void pwm_vibrator_play_work(struct work_struct *work)
+{
+ struct pwm_vibrator *vibrator = container_of(work,
+ struct pwm_vibrator, play_work);
+
+ if (vibrator->level)
+ pwm_vibrator_start(vibrator);
+ else
+ pwm_vibrator_stop(vibrator);
+}
+
+static int pwm_vibrator_play_effect(struct input_dev *dev, void *data,
+ struct ff_effect *effect)
+{
+ struct pwm_vibrator *vibrator = input_get_drvdata(dev);
+
+ vibrator->level = effect->u.rumble.strong_magnitude;
+ if (!vibrator->level)
+ vibrator->level = effect->u.rumble.weak_magnitude;
+
+ schedule_work(&vibrator->play_work);
+
+ return 0;
+}
+
+static void pwm_vibrator_close(struct input_dev *input)
+{
+ struct pwm_vibrator *vibrator = input_get_drvdata(input);
+
+ cancel_work_sync(&vibrator->play_work);
+ pwm_vibrator_stop(vibrator);
+}
+
+static int pwm_vibrator_probe(struct platform_device *pdev)
+{
+ struct pwm_vibrator *vibrator;
+ struct pwm_state state;
+ int err;
+
+ vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
+ if (!vibrator)
+ return -ENOMEM;
+
+ vibrator->input = devm_input_allocate_device(&pdev->dev);
+ if (!vibrator->input)
+ return -ENOMEM;
+
+ vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
+ err = PTR_ERR_OR_ZERO(vibrator->vcc);
+ if (err) {
+ if (err != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "Failed to request regulator: %d",
+ err);
+ return err;
+ }
+
+ vibrator->pwm = devm_pwm_get(&pdev->dev, "enable");
+ err = PTR_ERR_OR_ZERO(vibrator->pwm);
+ if (err) {
+ if (err != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "Failed to request main pwm: %d",
+ err);
+ return err;
+ }
+
+ INIT_WORK(&vibrator->play_work, pwm_vibrator_play_work);
+
+ /* Sync up PWM state and ensure it is off. */
+ pwm_init_state(vibrator->pwm, &state);
+ state.enabled = false;
+ err = pwm_apply_state(vibrator->pwm, &state);
+ if (err) {
+ dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
+ err);
+ return err;
+ }
+
+ vibrator->pwm_dir = devm_pwm_get(&pdev->dev, "direction");
+ err = PTR_ERR_OR_ZERO(vibrator->pwm_dir);
+ switch (err) {
+ case 0:
+ /* Sync up PWM state and ensure it is off. */
+ pwm_init_state(vibrator->pwm_dir, &state);
+ state.enabled = false;
+ err = pwm_apply_state(vibrator->pwm_dir, &state);
+ if (err) {
+ dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
+ err);
+ return err;
+ }
+
+ vibrator->direction_duty_cycle =
+ pwm_get_period(vibrator->pwm_dir) / 2;
+ device_property_read_u32(&pdev->dev, "direction-duty-cycle-ns",
+ &vibrator->direction_duty_cycle);
+ break;
+
+ case -ENODATA:
+ /* Direction PWM is optional */
+ vibrator->pwm_dir = NULL;
+ break;
+
+ default:
+ dev_err(&pdev->dev, "Failed to request direction pwm: %d", err);
+ /* Fall through */
+
+ case -EPROBE_DEFER:
+ return err;
+ }
+
+ vibrator->input->name = "pwm-vibrator";
+ vibrator->input->id.bustype = BUS_HOST;
+ vibrator->input->dev.parent = &pdev->dev;
+ vibrator->input->close = pwm_vibrator_close;
+
+ input_set_drvdata(vibrator->input, vibrator);
+ input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
+
+ err = input_ff_create_memless(vibrator->input, NULL,
+ pwm_vibrator_play_effect);
+ if (err) {
+ dev_err(&pdev->dev, "Couldn't create FF dev: %d", err);
+ return err;
+ }
+
+ err = input_register_device(vibrator->input);
+ if (err) {
+ dev_err(&pdev->dev, "Couldn't register input dev: %d", err);
+ return err;
+ }
+
+ platform_set_drvdata(pdev, vibrator);
+
+ return 0;
+}
+
+static int __maybe_unused pwm_vibrator_suspend(struct device *dev)
+{
+ struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
+
+ cancel_work_sync(&vibrator->play_work);
+ if (vibrator->level)
+ pwm_vibrator_stop(vibrator);
+
+ return 0;
+}
+
+static int __maybe_unused pwm_vibrator_resume(struct device *dev)
+{
+ struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
+
+ if (vibrator->level)
+ pwm_vibrator_start(vibrator);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(pwm_vibrator_pm_ops,
+ pwm_vibrator_suspend, pwm_vibrator_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id pwm_vibra_dt_match_table[] = {
+ { .compatible = "pwm-vibrator" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, pwm_vibra_dt_match_table);
+#endif
+
+static struct platform_driver pwm_vibrator_driver = {
+ .probe = pwm_vibrator_probe,
+ .driver = {
+ .name = "pwm-vibrator",
+ .pm = &pwm_vibrator_pm_ops,
+ .of_match_table = of_match_ptr(pwm_vibra_dt_match_table),
+ },
+};
+module_platform_driver(pwm_vibrator_driver);
+
+MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
+MODULE_DESCRIPTION("PWM vibrator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pwm-vibrator");
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