--- /dev/null
+/*
+ * Regulator haptic driver
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Author: Jaewon Kim <jaewon02.kim@samsung.com>
+ * Author: Hyunhee Kim <hyunhee.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_data/regulator-haptic.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#define MAX_MAGNITUDE_SHIFT 16
+
+struct regulator_haptic {
+ struct device *dev;
+ struct input_dev *input_dev;
+ struct regulator *regulator;
+
+ struct work_struct work;
+ struct mutex mutex;
+
+ bool active;
+ bool suspended;
+
+ unsigned int max_volt;
+ unsigned int min_volt;
+ unsigned int magnitude;
+};
+
+static int regulator_haptic_toggle(struct regulator_haptic *haptic, bool on)
+{
+ int error;
+
+ if (haptic->active != on) {
+
+ error = on ? regulator_enable(haptic->regulator) :
+ regulator_disable(haptic->regulator);
+ if (error) {
+ dev_err(haptic->dev,
+ "failed to switch regulator %s: %d\n",
+ on ? "on" : "off", error);
+ return error;
+ }
+
+ haptic->active = on;
+ }
+
+ return 0;
+}
+
+static int regulator_haptic_set_voltage(struct regulator_haptic *haptic,
+ unsigned int magnitude)
+{
+ u64 volt_mag_multi;
+ unsigned int intensity;
+ int error;
+
+ volt_mag_multi = (u64)(haptic->max_volt - haptic->min_volt) * magnitude;
+ intensity = (unsigned int)(volt_mag_multi >> MAX_MAGNITUDE_SHIFT);
+
+ error = regulator_set_voltage(haptic->regulator,
+ intensity + haptic->min_volt,
+ haptic->max_volt);
+ if (error) {
+ dev_err(haptic->dev, "cannot set regulator voltage to %d: %d\n",
+ intensity + haptic->min_volt, error);
+ return error;
+ }
+
+ return 0;
+}
+
+static void regulator_haptic_work(struct work_struct *work)
+{
+ struct regulator_haptic *haptic = container_of(work,
+ struct regulator_haptic, work);
+ unsigned int magnitude;
+ int error;
+
+ mutex_lock(&haptic->mutex);
+
+ if (haptic->suspended)
+ goto out;
+
+ magnitude = ACCESS_ONCE(haptic->magnitude);
+
+ error = regulator_haptic_set_voltage(haptic, magnitude);
+ if (error)
+ goto out;
+
+ regulator_haptic_toggle(haptic, magnitude != 0);
+
+out:
+ mutex_unlock(&haptic->mutex);
+}
+
+static int regulator_haptic_play_effect(struct input_dev *input, void *data,
+ struct ff_effect *effect)
+{
+ struct regulator_haptic *haptic = input_get_drvdata(input);
+
+ haptic->magnitude = effect->u.rumble.strong_magnitude;
+ if (!haptic->magnitude)
+ haptic->magnitude = effect->u.rumble.weak_magnitude;
+
+ schedule_work(&haptic->work);
+
+ return 0;
+}
+
+static void regulator_haptic_close(struct input_dev *input)
+{
+ struct regulator_haptic *haptic = input_get_drvdata(input);
+
+ cancel_work_sync(&haptic->work);
+ regulator_haptic_set_voltage(haptic, 0);
+ regulator_haptic_toggle(haptic, false);
+}
+
+static int __maybe_unused
+regulator_haptic_parse_dt(struct device *dev, struct regulator_haptic *haptic)
+{
+ struct device_node *node;
+ int error;
+
+ node = dev->of_node;
+ if(!node) {
+ dev_err(dev, "Missing dveice tree data\n");
+ return -EINVAL;
+ }
+
+ error = of_property_read_u32(node, "max-microvolt", &haptic->max_volt);
+ if (error) {
+ dev_err(dev, "cannot parse max-microvolt\n");
+ return error;
+ }
+
+ error = of_property_read_u32(node, "min-microvolt", &haptic->min_volt);
+ if (error) {
+ dev_err(dev, "cannot parse min-microvolt\n");
+ return error;
+ }
+
+ return 0;
+}
+
+static int regulator_haptic_probe(struct platform_device *pdev)
+{
+ const struct regulator_haptic_data *pdata = dev_get_platdata(&pdev->dev);
+ struct regulator_haptic *haptic;
+ struct input_dev *input_dev;
+ int error;
+
+ haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
+ if (!haptic)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, haptic);
+ haptic->dev = &pdev->dev;
+ mutex_init(&haptic->mutex);
+ INIT_WORK(&haptic->work, regulator_haptic_work);
+
+ if (pdata) {
+ haptic->max_volt = pdata->max_volt;
+ haptic->min_volt = pdata->min_volt;
+ } else if (IS_ENABLED(CONFIG_OF)) {
+ error = regulator_haptic_parse_dt(&pdev->dev, haptic);
+ if (error)
+ return error;
+ } else {
+ dev_err(&pdev->dev, "Missing platform data\n");
+ return -EINVAL;
+ }
+
+ haptic->regulator = devm_regulator_get_exclusive(&pdev->dev, "haptic");
+ if (IS_ERR(haptic->regulator)) {
+ dev_err(&pdev->dev, "failed to get regulator\n");
+ return PTR_ERR(haptic->regulator);
+ }
+
+ input_dev = devm_input_allocate_device(&pdev->dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ haptic->input_dev = input_dev;
+ haptic->input_dev->name = "regulator-haptic";
+ haptic->input_dev->dev.parent = &pdev->dev;
+ haptic->input_dev->close = regulator_haptic_close;
+ input_set_drvdata(haptic->input_dev, haptic);
+ input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+ error = input_ff_create_memless(input_dev, NULL,
+ regulator_haptic_play_effect);
+ if (error) {
+ dev_err(&pdev->dev, "failed to create force-feedback\n");
+ return error;
+ }
+
+ error = input_register_device(haptic->input_dev);
+ if (error) {
+ dev_err(&pdev->dev, "failed to register input device\n");
+ return error;
+ }
+
+ return 0;
+}
+
+static int __maybe_unused regulator_haptic_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+ int error;
+
+ error = mutex_lock_interruptible(&haptic->mutex);
+ if (error)
+ return error;
+
+ regulator_haptic_set_voltage(haptic, 0);
+ regulator_haptic_toggle(haptic, false);
+
+ haptic->suspended = true;
+
+ mutex_unlock(&haptic->mutex);
+
+ return 0;
+}
+
+static int __maybe_unused regulator_haptic_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+ unsigned int magnitude;
+
+ mutex_lock(&haptic->mutex);
+
+ haptic->suspended = false;
+
+ magnitude = ACCESS_ONCE(haptic->magnitude);
+ if (magnitude) {
+ regulator_haptic_set_voltage(haptic, magnitude);
+ regulator_haptic_toggle(haptic, true);
+ }
+
+ mutex_unlock(&haptic->mutex);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(regulator_haptic_pm_ops,
+ regulator_haptic_suspend, regulator_haptic_resume);
+
+static struct of_device_id regulator_haptic_dt_match[] = {
+ { .compatible = "regulator-haptic" },
+ { /* sentinel */ },
+};
+
+static struct platform_driver regulator_haptic_driver = {
+ .probe = regulator_haptic_probe,
+ .driver = {
+ .name = "regulator-haptic",
+ .of_match_table = regulator_haptic_dt_match,
+ .pm = ®ulator_haptic_pm_ops,
+ },
+};
+module_platform_driver(regulator_haptic_driver);
+
+MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
+MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
+MODULE_DESCRIPTION("Regulator haptic driver");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-rpi.git / commitdiff