--- /dev/null
+/*
+ * MAXIM MAX77693 Haptic device driver
+ *
+ * Copyright (C) 2014 Samsung Electronics
+ * Jaewon Kim <jaewon02.kim@samsung.com>
+ *
+ * This program is not provided / owned by Maxim Integrated Products.
+ *
+ * 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/err.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/max77693.h>
+#include <linux/mfd/max77693-private.h>
+
+#define MAX_MAGNITUDE_SHIFT 16
+
+enum max77693_haptic_motor_type {
+ MAX77693_HAPTIC_ERM = 0,
+ MAX77693_HAPTIC_LRA,
+};
+
+enum max77693_haptic_pulse_mode {
+ MAX77693_HAPTIC_EXTERNAL_MODE = 0,
+ MAX77693_HAPTIC_INTERNAL_MODE,
+};
+
+enum max77693_haptic_pwm_divisor {
+ MAX77693_HAPTIC_PWM_DIVISOR_32 = 0,
+ MAX77693_HAPTIC_PWM_DIVISOR_64,
+ MAX77693_HAPTIC_PWM_DIVISOR_128,
+ MAX77693_HAPTIC_PWM_DIVISOR_256,
+};
+
+struct max77693_haptic {
+ struct regmap *regmap_pmic;
+ struct regmap *regmap_haptic;
+ struct device *dev;
+ struct input_dev *input_dev;
+ struct pwm_device *pwm_dev;
+ struct regulator *motor_reg;
+
+ bool enabled;
+ bool suspend_state;
+ unsigned int magnitude;
+ unsigned int pwm_duty;
+ enum max77693_haptic_motor_type type;
+ enum max77693_haptic_pulse_mode mode;
+ enum max77693_haptic_pwm_divisor pwm_divisor;
+
+ struct work_struct work;
+};
+
+static int max77693_haptic_set_duty_cycle(struct max77693_haptic *haptic)
+{
+ int delta = (haptic->pwm_dev->period + haptic->pwm_duty) / 2;
+ int error;
+
+ error = pwm_config(haptic->pwm_dev, delta, haptic->pwm_dev->period);
+ if (error) {
+ dev_err(haptic->dev, "failed to configure pwm: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static int max77693_haptic_configure(struct max77693_haptic *haptic,
+ bool enable)
+{
+ unsigned int value;
+ int error;
+
+ value = ((haptic->type << MAX77693_CONFIG2_MODE) |
+ (enable << MAX77693_CONFIG2_MEN) |
+ (haptic->mode << MAX77693_CONFIG2_HTYP) |
+ (haptic->pwm_divisor));
+
+ error = regmap_write(haptic->regmap_haptic,
+ MAX77693_HAPTIC_REG_CONFIG2, value);
+ if (error) {
+ dev_err(haptic->dev,
+ "failed to update haptic config: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static int max77693_haptic_lowsys(struct max77693_haptic *haptic, bool enable)
+{
+ int error;
+
+ error = regmap_update_bits(haptic->regmap_pmic,
+ MAX77693_PMIC_REG_LSCNFG,
+ MAX77693_PMIC_LOW_SYS_MASK,
+ enable << MAX77693_PMIC_LOW_SYS_SHIFT);
+ if (error) {
+ dev_err(haptic->dev, "cannot update pmic regmap: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static void max77693_haptic_enable(struct max77693_haptic *haptic)
+{
+ int error;
+
+ if (haptic->enabled)
+ return;
+
+ error = pwm_enable(haptic->pwm_dev);
+ if (error) {
+ dev_err(haptic->dev,
+ "failed to enable haptic pwm device: %d\n", error);
+ return;
+ }
+
+ error = max77693_haptic_lowsys(haptic, true);
+ if (error)
+ goto err_enable_lowsys;
+
+ error = max77693_haptic_configure(haptic, true);
+ if (error)
+ goto err_enable_config;
+
+ haptic->enabled = true;
+
+ return;
+
+err_enable_config:
+ max77693_haptic_lowsys(haptic, false);
+err_enable_lowsys:
+ pwm_disable(haptic->pwm_dev);
+}
+
+static void max77693_haptic_disable(struct max77693_haptic *haptic)
+{
+ int error;
+
+ if (haptic->enabled)
+ return;
+
+ error = max77693_haptic_configure(haptic, false);
+ if (error)
+ return;
+
+ error = max77693_haptic_lowsys(haptic, false);
+ if (error)
+ goto err_disable_lowsys;
+
+ pwm_disable(haptic->pwm_dev);
+ haptic->enabled = false;
+
+ return;
+
+err_disable_lowsys:
+ max77693_haptic_configure(haptic, true);
+}
+
+static void max77693_haptic_play_work(struct work_struct *work)
+{
+ struct max77693_haptic *haptic =
+ container_of(work, struct max77693_haptic, work);
+ int error;
+
+ error = max77693_haptic_set_duty_cycle(haptic);
+ if (error) {
+ dev_err(haptic->dev, "failed to set duty cycle: %d\n", error);
+ return;
+ }
+
+ if (haptic->magnitude)
+ max77693_haptic_enable(haptic);
+ else
+ max77693_haptic_disable(haptic);
+}
+
+static int max77693_haptic_play_effect(struct input_dev *dev, void *data,
+ struct ff_effect *effect)
+{
+ struct max77693_haptic *haptic = input_get_drvdata(dev);
+ uint64_t period_mag_multi;
+
+ haptic->magnitude = effect->u.rumble.strong_magnitude;
+ if (!haptic->magnitude)
+ haptic->magnitude = effect->u.rumble.weak_magnitude;
+
+ /*
+ * The magnitude comes from force-feedback interface.
+ * The formula to convert magnitude to pwm_duty as follows:
+ * - pwm_duty = (magnitude * pwm_period) / MAX_MAGNITUDE(0xFFFF)
+ */
+ period_mag_multi = (int64_t)(haptic->pwm_dev->period *
+ haptic->magnitude);
+ haptic->pwm_duty = (unsigned int)(period_mag_multi >>
+ MAX_MAGNITUDE_SHIFT);
+
+ schedule_work(&haptic->work);
+
+ return 0;
+}
+
+static int max77693_haptic_open(struct input_dev *dev)
+{
+ struct max77693_haptic *haptic = input_get_drvdata(dev);
+ int error;
+
+ error = regulator_enable(haptic->motor_reg);
+ if (error) {
+ dev_err(haptic->dev,
+ "failed to enable regulator: %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static void max77693_haptic_close(struct input_dev *dev)
+{
+ struct max77693_haptic *haptic = input_get_drvdata(dev);
+ int error;
+
+ cancel_work_sync(&haptic->work);
+ max77693_haptic_disable(haptic);
+
+ error = regulator_disable(haptic->motor_reg);
+ if (error)
+ dev_err(haptic->dev,
+ "failed to disable regulator: %d\n", error);
+}
+
+static int max77693_haptic_probe(struct platform_device *pdev)
+{
+ struct max77693_dev *max77693 = dev_get_drvdata(pdev->dev.parent);
+ struct max77693_haptic *haptic;
+ int error;
+
+ haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
+ if (!haptic)
+ return -ENOMEM;
+
+ haptic->regmap_pmic = max77693->regmap;
+ haptic->regmap_haptic = max77693->regmap_haptic;
+ haptic->dev = &pdev->dev;
+ haptic->type = MAX77693_HAPTIC_LRA;
+ haptic->mode = MAX77693_HAPTIC_EXTERNAL_MODE;
+ haptic->pwm_divisor = MAX77693_HAPTIC_PWM_DIVISOR_128;
+ haptic->suspend_state = false;
+
+ INIT_WORK(&haptic->work, max77693_haptic_play_work);
+
+ /* Get pwm and regulatot for haptic device */
+ haptic->pwm_dev = devm_pwm_get(&pdev->dev, NULL);
+ if (IS_ERR(haptic->pwm_dev)) {
+ dev_err(&pdev->dev, "failed to get pwm device\n");
+ return PTR_ERR(haptic->pwm_dev);
+ }
+
+ haptic->motor_reg = devm_regulator_get(&pdev->dev, "haptic");
+ if (IS_ERR(haptic->motor_reg)) {
+ dev_err(&pdev->dev, "failed to get regulator\n");
+ return PTR_ERR(haptic->motor_reg);
+ }
+
+ /* Initialize input device for haptic device */
+ haptic->input_dev = devm_input_allocate_device(&pdev->dev);
+ if (!haptic->input_dev) {
+ dev_err(&pdev->dev, "failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ haptic->input_dev->name = "max77693-haptic";
+ haptic->input_dev->id.version = 1;
+ haptic->input_dev->dev.parent = &pdev->dev;
+ haptic->input_dev->open = max77693_haptic_open;
+ haptic->input_dev->close = max77693_haptic_close;
+ input_set_drvdata(haptic->input_dev, haptic);
+ input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+ error = input_ff_create_memless(haptic->input_dev, NULL,
+ max77693_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;
+ }
+
+ platform_set_drvdata(pdev, haptic);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max77693_haptic_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct max77693_haptic *haptic = platform_get_drvdata(pdev);
+
+ if (haptic->enabled) {
+ max77693_haptic_disable(haptic);
+ haptic->suspend_state = true;
+ }
+
+ return 0;
+}
+
+static int max77693_haptic_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct max77693_haptic *haptic = platform_get_drvdata(pdev);
+
+ if (haptic->suspend_state) {
+ max77693_haptic_enable(haptic);
+ haptic->suspend_state = false;
+ }
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(max77693_haptic_pm_ops,
+ max77693_haptic_suspend, max77693_haptic_resume);
+
+static struct platform_driver max77693_haptic_driver = {
+ .driver = {
+ .name = "max77693-haptic",
+ .owner = THIS_MODULE,
+ .pm = &max77693_haptic_pm_ops,
+ },
+ .probe = max77693_haptic_probe,
+};
+module_platform_driver(max77693_haptic_driver);
+
+MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
+MODULE_DESCRIPTION("MAXIM MAX77693 Haptic driver");
+MODULE_ALIAS("platform:max77693-haptic");
+MODULE_LICENSE("GPL");