/* * Regulator haptic driver * * Copyright (c) 2014 Samsung Electronics Co., Ltd. * Author: Jaewon Kim * Author: Hyunhee Kim * * 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 #include #include #include #include #include #include #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 "); MODULE_AUTHOR("Hyunhee Kim "); MODULE_DESCRIPTION("Regulator haptic driver"); MODULE_LICENSE("GPL");